We thank Mr. Quentin Collier for his assistance with the creation of the video.

The following protocol follows the guidelines of the University of Calgary Conjoint Health Research Ethics Board. Informed media consent for the procedure was obtained and the patient provided written consent for this publication.
1. Positioning and pre-procedure setup
<ol>
	<li>Obtain a preoperative cranial MRI or computed tomography (CT) with the appropriate neuronavigation protocol.</li>
	<li>Place the patient supine on a donut headrest with the head turned toward the contralateral side and place a shoulder roll to augment the exposure of the occipital region (Figure 3).</li>
	<li>Upload the patient&#39;s preoperative cranial MRI or CT, register it to the neuronavigation system, and complete the neuronavigation workstation planning.</li>
	<li>Select an entry point and target for the proximal catheter and mark the specific entry location on the patient&#39;s scalp. 
	NOTE: By standard, a right-sided posterior approach is preferred, unless precluded by the patient&#39;s circumstances. An ideal entry point is one with a trajectory that traverses minimal parenchyma while missing any identifiable vessels in its path to the body of the right lateral ventricle (Figure 3).</li>
	<li>Mark an inverted u-shaped (horseshoe-shaped) incision to incorporate the entry point. Shave any hair surrounding the incision with a clipper (Figure 3).</li>
	<li>Mark a 1 cm para-midline abdominal incision at the junction, immediately inferior and right lateral to the xiphisternum.</li>
	<li>Infiltrate the scalp incision with a local anesthetic.</li>
	<li>Adhere to a strict infection-prevention protocol (bundle) (Figure 4)38.</li>
	<li>Prepare the entire surgical field with a 2% chlorhexidine gluconate/70% isopropyl alcohol solution and allow it to dry for at least 3 min before starting the operative draping. 
	&#8203;NOTE: Prior to operative draping, all scrubbed surgical staff must double glove, and must change their outer gloves for new ones after draping of the patient is completed.</li>
	<li>Drape the entire surgical field with an antimicrobial incise drape, which will help hold the drapes in place and reduce the surgical team&#39;s direct contact with the skin.</li>
	<li>Apply a standard laparoscopic drape and extend the opening in a cranial direction to the edges of the draping to allow exposure of the cranium and chest surgical field.</li>
</ol>
2. Cranial exposure
<ol>
	<li>Use a #15 scalpel to score the horseshoe-shaped incision.</li>
	<li>Use a fine-tip monopolar cautery to deepen the incision, making sure to preserve the periosteal layer.</li>
	<li>Retract the skin edges with a self-retaining retractor.</li>
	<li>Make a cruciate periosteal incision in the center of the wound to expose the skull using monopolar cautery.</li>
	<li>Make an approximately 2 cm burr hole in the center of the periosteal exposure, ensuring the underlying dura is preserved (Figure 5).</li>
</ol>
3. Subcutaneous distal catheter placement
<ol>
	<li>Make a para-midline sub-xiphisternum incision down to the perifascial fat layer.</li>
	<li>Blunt dissect the subcutaneous tissue 2-3 cm in a cranial direction.</li>
	<li>Carefully guide a tunneling stylet with its encasing plastic sheath within the subcutaneous layer and pass it toward the cranial incision, taking every caution to stay above the ribs and clavicle, and avoid piercing the skin.</li>
	<li>Once the inferior aspect of the cranial incision is pierced by the tunneller, withdraw the stylet, leaving the plastic sheath in place (Figure 5).</li>
	<li>Create a subgaleal pocket at the inferior edge of the cranial incision around the plastic sheath that is sizable enough to bury the shunt reservoir using monopolar cautery and blunt dissection with Kelly forceps.</li>
	<li>Remove the distal catheter from the sterile packaging and place it in sterile saline.</li>
	<li>Thread the distal catheter through the plastic sheath from cranial to caudal direction, minimizing contact of the shunt components with the drapes, and then remove the plastic sheath.</li>
	<li>Prime the system with sterile saline solution to remove any air.</li>
	<li>Valve attachment
	<ol>
		<li>If a programmable shunt valve is used, program it to the desired setting before it is removed from the packaging. Remove the VP shunt valve and distal catheters from the sterile packaging and place the components in sterile saline.</li>
		<li>Attach the distal port of the valve to the proximal end of the distal catheter, secure it twice with 3-0 silk ties, and prime the system with sterile saline solution to remove any residual air locks. Wrap the valve and the exposed catheter in a saline-soaked sponge making every attempt to prevent the shunt system from touching the drapes.</li>
	</ol>
	</li>
</ol>
4. Ventricular (proximal) catheter insertion
<ol>
	<li>Remove the ventricular catheter from the sterile packaging and place it in sterile saline.</li>
	<li>Create a small centrally located circular durotomy equivalent to the diameter of the proximal catheter (incorporating the underlying pia and arachnoid) using a fine tip monopolar cautery.</li>
	<li>With the navigation stylet within the proximal catheter, pass the catheter into the ipsilateral ventricle using real-time navigation along the preprogrammed trajectory to the target depth. 
	NOTE: Often, there is CSF flow at about 5 cm, however, ensure to advance the catheter further to a depth of approximately 8-10 cm (target).</li>
	<li>Once at the target depth, remove the navigation stylet probe from the ventricular catheter and confirm free CSF flow. Then clamp the catheter with a snap using booties to protect the catheter.</li>
	<li>Trim the proximal catheter, leaving about 2 cm extra from the outer table of the skull (Figure 5).</li>
	<li>Attach the distal end of the proximal catheter to the proximal outlet of the valve and secure it twice with 3-0 silk ties.</li>
	<li>Carefully place the valve into the subgaleal pocket and anchor the valve sleeve to the preserved periosteum with a 4-0 silk suture.</li>
	<li>Apply gentle traction on the distal catheter at the abdominal incision to ensure no catheter kinks exist.</li>
	<li>Confirm that the spontaneous flow of CSF is at the very distal (abdominal) end of the shunt system.</li>
</ol>
5. Intrabdominal (distal) catheter placement
NOTE: The distal catheter is placed laparoscopically within the peritoneal cavity, ideally by a general surgeon.
<ol>
	<li>Make a curvilinear periumbilical incision with a #15 scalpel followed by blunt dissection down to the abdominal wall fascia.</li>
	<li>Grasp the fascia on each side with Kocher forceps and incise it in a vertical fashion, to ensure entry into the peritoneal cavity.</li>
	<li>Place #2 polyglactin stay sutures through the fascia on either side, then insert a blunt Hasson trocar.</li>
	<li>Insufflate the abdomen with carbon dioxide (CO2).</li>
	<li>Insert a at 30&#176; angled laparoscope through the Hasson trocar access port (Figure 6).</li>
	<li>Place a 5 mm port in standard fashion under direct vision, usually on the left, but this may vary depending on the density and position of intraperitoneal adhesions (Figure 6).</li>
	<li>Perform any lysis of adhesions, that may be required.</li>
	<li>Make a small hole in the falciform ligament (from the left side of the ligament) using a combination of electrocautery and laparoscopic Metzenbaum scissors (Figure 6). The hole must be as close to both the liver and diaphragm as safely possible (cephalad).</li>
	<li>Create a transverse abdominal tunnel for the VP shunt catheter using the electrocautery hook at the incision created in step 3.1 (where the distal catheter exits from the subcutaneous space).</li>
	<li>Insert the distal VP shunt catheter into the peritoneal cavity through the path created with a 11F peel-away sheath introducer.</li>
	<li>Once the catheter is visualized in the abdominal cavity, grasp and position it, through the hole in the falciform ligament (Figure 6).</li>
	<li>Pull the remaining catheter through the falciform ligament hole from the right side and tuck it behind the liver (following medial mobilization of the right posterior liver sector). The catheter&#39;s final resting place must be the retrohepatic space (Figure 6).</li>
	<li>Trim the catheter such that the end is located just above the inferior margin of the liver. The final position of the catheter should ideally be inferior to the diaphragm but superior and posterior to the mobilized liver, immediately superior to the right pericolic gutter. Confirm there is still spontaneous CSF flow through the catheter under direct visualization (Figure 6). 
	NOTE: There is no predetermined length of the catheter. The catheter is trimmed to fit the patient&#39;s anatomy intracorporeally.</li>
	<li>Remove the residual (trimmed part of the catheter) through the 5 mm side port.</li>
	<li>Deflate the abdomen slowly and cautiously to ensure no migration of the catheter, and then remove all instruments.</li>
</ol>
6. Closure
<ol>
	<li>Close the cranial wound in a layered fashion with 3-0 polyglactin simple interrupted buried sutures in the galea layer and staples in the skin. Apply a dressing.</li>
	<li>Close the abdominal fascia using the previously placed polyglactin stay sutures followed by 4-0 poliglecaprone-25 subcuticular sutures and acrylate adhesive for skin closure. Apply a surgical dressing.</li>
</ol>

<ol>
	<li>Isaacs, A. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Age-specific+global+epidemiology+of+hydrocephalus:+Systematic+review,+metanalysis+and+global+birth+surveillance.">Age-specific global epidemiology of hydrocephalus: Systematic review, metanalysis and global birth surveillance.</a> PLoS One. 13 (10), 0204926 (2018).</li><li>Rekate, H. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+contemporary+definition+and+classification+of+hydrocephalus.">A contemporary definition and classification of hydrocephalus.</a> Seminars in Pediatric Neurology. 16 (1), 9-15 (2009).</li><li>Del Bigio, M. R., Di Curzio, D. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nonsurgical+therapy+for+hydrocephalus:+a+comprehensive+and+critical+review.">Nonsurgical therapy for hydrocephalus: a comprehensive and critical review.</a> Fluids and Barriers of the CNS. 13 (1), 3 (2016).</li><li>Reddy, G. K., Bollam, P., Shi, R., Guthikonda, B., Nanda, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Management+of+adult+hydrocephalus+with+ventriculoperitoneal+shunts:+Long-term+single-institution+experience.">Management of adult hydrocephalus with ventriculoperitoneal shunts: Long-term single-institution experience.</a> Neurosurgery. 69 (4), 780-771 (2011).</li><li>Isaacs, A. M., Williams, M. A., Hamilton, M. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Current+update+on+treatment+strategies+for+idiopathic+normal+pressure+hydrocephalus.">Current update on treatment strategies for idiopathic normal pressure hydrocephalus.</a> Current Treatment and Options in Neurology. 21 (12), 65 (2019).</li><li>Isaacs, A. M., Krahn, D., Walker, A. M., Hurdle, H., Hamilton, M. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transesophageal+echocardiography-guided+ventriculoatrial+shunt+insertion.">Transesophageal echocardiography-guided ventriculoatrial shunt insertion.</a> Operative Neurosurgery. 19 (1), 25-31 (2020).</li><li>Hung, A. L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ventriculoatrial+versus+ventriculoperitoneal+shunt+complications+in+idiopathic+normal+pressure+hydrocephalus.">Ventriculoatrial versus ventriculoperitoneal shunt complications in idiopathic normal pressure hydrocephalus.</a> Clinical Neurology and Neurosurgery. 157, 1-6 (2017).</li><li>Kazui, H., Miyajima, M., Mori, E., Ishikawa, M., Investigators, S. -. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lumboperitoneal+shunt+surgery+for+idiopathic+normal+pressure+hydrocephalus+(SINPHONI-2):+An+open-label+randomised+trial.">Lumboperitoneal shunt surgery for idiopathic normal pressure hydrocephalus (SINPHONI-2): An open-label randomised trial.</a> Lancet Neurology. 14 (6), 585-594 (2015).</li><li>Khan, F., Rehman, A., Shamim, M. S., Bari, M. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Factors+affecting+ventriculoperitoneal+shunt+survival+in+adult+patients.">Factors affecting ventriculoperitoneal shunt survival in adult patients.</a> Surgical Neurology International. 6, 25 (2015).</li><li>Lund-Johansen, M., Svendsen, F., Wester, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Shunt+failures+and+complications+in+adults+as+related+to+shunt+type,+diagnosis,+and+the+experience+of+the+surgeon.">Shunt failures and complications in adults as related to shunt type, diagnosis, and the experience of the surgeon.</a> Neurosurgery. 35 (5), 839-844 (1994).</li><li>Anderson, I. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Factors+associated+with+30-day+ventriculoperitoneal+shunt+failure+in+pediatric+and+adult+patients.">Factors associated with 30-day ventriculoperitoneal shunt failure in pediatric and adult patients.</a> Journal of Neurosurgery. 130 (1), 145-153 (2018).</li><li>Korinek, A. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Morbidity+of+ventricular+cerebrospinal+fluid+shunt+surgery+in+adults:+an+8-year+study.">Morbidity of ventricular cerebrospinal fluid shunt surgery in adults: an 8-year study.</a> Neurosurgery. 68 (4), 985-994 (2011).</li><li>Albanese, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Antibiotic-impregnated+ventriculo-peritoneal+shunts+in+patients+at+high+risk+of+infection.">Antibiotic-impregnated ventriculo-peritoneal shunts in patients at high risk of infection.</a> Acta Neurochirurgica (Wien). 151 (10), 1259-1263 (2009).</li><li>Reddy, G. K., Bollam, P., Caldito, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ventriculoperitoneal+shunt+surgery+and+the+risk+of+shunt+infection+in+patients+with+hydrocephalus:+Long-term+single+institution+experience.">Ventriculoperitoneal shunt surgery and the risk of shunt infection in patients with hydrocephalus: Long-term single institution experience.</a> World Neurosurgery. 78 (1-2), 155-163 (2012).</li><li>Lundar, T., Langmoen, I. A., Hovind, K. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Shunt+failure+caused+by+valve+collapse.">Shunt failure caused by valve collapse.</a> Journal of Neurology, Neurosurgery, Psychiatry. 54 (6), 559-560 (1991).</li><li>Leibold, A. T., Weyhenmeyer, J., Rodgers, R., Lee, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ventriculoperitoneal+shunt+valve+fracture+after+traumatic+motor+vehicle+collision.">Ventriculoperitoneal shunt valve fracture after traumatic motor vehicle collision.</a> Interdisciplinary Neurosurgery. 16, 79-81 (2019).</li><li>Sainte-Rose, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Shunt+obstruction:+A+preventable+complication.">Shunt obstruction: A preventable complication.</a> Pediatric Neurosurgery. 19 (3), 156-164 (1993).</li><li>Hamilton, M. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Treatment+of+hydrocephalus+in+adults.">Treatment of hydrocephalus in adults.</a> Seminars in Pediatric Neurology. 16 (1), 34-41 (2009).</li><li>Jaraj, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Prevalence+of+idiopathic+normal-pressure+hydrocephalus.">Prevalence of idiopathic normal-pressure hydrocephalus.</a> Neurology. 82 (16), 1449-1454 (2014).</li><li>Williams, M. A., Sharkey, P., van Doren, D., Thomas, G., Rigamonti, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Influence+of+shunt+surgery+on+healthcare+expenditures+of+elderly+fee-for-service+Medicare+beneficiaries+with+hydrocephalus.">Influence of shunt surgery on healthcare expenditures of elderly fee-for-service Medicare beneficiaries with hydrocephalus.</a> Journal in Neurosurgery. 107 (1), 21-28 (2007).</li><li>Rosenbaum, B. P., Vadera, S., Kelly, M. L., Kshettry, V. R., Weil, R. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ventriculostomy:+Frequency,+length+of+stay+and+in-hospital+mortality+in+the+United+States+of+America,+1988-2010.">Ventriculostomy: Frequency, length of stay and in-hospital mortality in the United States of America, 1988-2010.</a> Journal of Clinical Neurosciences. 21 (4), 623-632 (2014).</li><li>Smith, E. R., Butler, W. E., Barker, F. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In-hospital+mortality+rates+after+ventriculoperitoneal+shunt+procedures+in+the+United+States,+1998+to+2000:+Relation+to+hospital+and+surgeon+volume+of+care.">In-hospital mortality rates after ventriculoperitoneal shunt procedures in the United States, 1998 to 2000: Relation to hospital and surgeon volume of care.</a> Jouranl of Neurosurgery. 100, 90-97 (1998).</li><li>Simon, T. D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hospital+care+for+children+with+hydrocephalus+in+the+United+States:+utilization,+charges,+comorbidities,+and+deaths.">Hospital care for children with hydrocephalus in the United States: utilization, charges, comorbidities, and deaths.</a> Journal of Neurosurgery: Pediatrics. 1 (2), 131-137 (2008).</li><li>Tullberg, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Shunt+surgery+in+idiopathic+normal+pressure+hydrocephalus+is+cost-effective-a+cost+utility+analysis.">Shunt surgery in idiopathic normal pressure hydrocephalus is cost-effective-a cost utility analysis.</a> Acta Neurochirurgica (Wien). 160 (3), 509-518 (2018).</li><li>Tubbs, R. S., Maher, C. O., Young, R. L., Cohen-Gadol, A. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Distal+revision+of+ventriculoperitoneal+shunts+using+a+peel-away+sheath).">Distal revision of ventriculoperitoneal shunts using a peel-away sheath).</a> Journal of Neurosurgery: Pediatrics. 4 (4), 402-405 (2009).</li><li>Naftel, R. P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Laparoscopic+versus+open+insertion+of+the+peritoneal+catheter+in+ventriculoperitoneal+shunt+placement:+Review+of+810+consecutive+cases.">Laparoscopic versus open insertion of the peritoneal catheter in ventriculoperitoneal shunt placement: Review of 810 consecutive cases.</a> Journal of Neurosurgery. 115 (1), 151-158 (2011).</li><li>Lind, C. R., Tsai, A. M., Lind, C. J., Law, A. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ventricular+catheter+placement+accuracy+in+non-stereotactic+shunt+surgery+for+hydrocephalus.">Ventricular catheter placement accuracy in non-stereotactic shunt surgery for hydrocephalus.</a> Journal of Clinical Neurosciences. 16 (7), 918-920 (2009).</li><li>Reddy, G. K., Bollam, P., Caldito, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Long-term+outcomes+of+ventriculoperitoneal+shunt+surgery+in+patients+with+hydrocephalus.">Long-term outcomes of ventriculoperitoneal shunt surgery in patients with hydrocephalus.</a> World Neurosurgery. 81 (2), 404-410 (2014).</li><li>Puca, A., Anile, C., Maira, G., Rossi, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cerebrospinal+fluid+shunting+for+hydrocephalus+in+the+adult:+factors+related+to+shunt+revision.">Cerebrospinal fluid shunting for hydrocephalus in the adult: factors related to shunt revision.</a> Neurosurgery. 29 (6), 822-826 (1991).</li><li>Paff, M., Alexandru-Abrams, D., Muhonen, M., Loudon, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ventriculoperitoneal+shunt+complications:+A+review.">Ventriculoperitoneal shunt complications: A review.</a> Interdisciplinary Neurosurgery. 13, 66-70 (2018).</li><li>Cozzens, J. W., Chandler, J. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Increased+risk+of+distal+ventriculoperitoneal+shunt+obstruction+associated+with+slit+valves+or+distal+slits+in+the+peritoneal+catheter.">Increased risk of distal ventriculoperitoneal shunt obstruction associated with slit valves or distal slits in the peritoneal catheter.</a> Journal of Neurosurgery. 87 (5), 682-686 (1997).</li><li>Hayhurst, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+electromagnetic-navigated+shunt+placement+on+failure+rates:+a+prospective+multicenter+study.">Effect of electromagnetic-navigated shunt placement on failure rates: a prospective multicenter study.</a> Journal of Neurosurgery. 113 (6), 1273-1278 (2010).</li><li>Shao, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+laparoscopic+approach+to+ventriculoperitoneal+shunt+placement+with+a+novel+fixation+method+for+distal+shunt+catheter+in+the+treatment+of+hydrocephalus.">A laparoscopic approach to ventriculoperitoneal shunt placement with a novel fixation method for distal shunt catheter in the treatment of hydrocephalus.</a> Minimum Invasive Neurosurgery. 54 (1), 44-47 (2011).</li><li>Kestle, J. R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+new+Hydrocephalus+Clinical+Research+Network+protocol+to+reduce+cerebrospinal+fluid+shunt+infection.">A new Hydrocephalus Clinical Research Network protocol to reduce cerebrospinal fluid shunt infection.</a> Journal of Neurosurgery Pediatrics. 17 (4), 391-396 (2016).</li><li>Svoboda, S. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preventing+distal+catheter+obstruction+in+laparoscopic+ventriculoperitoneal+shunt+placement+in+adults:+The+&amp;#34;Falciform+Technique&amp;#34;.">Preventing distal catheter obstruction in laparoscopic ventriculoperitoneal shunt placement in adults: The &amp;#34;Falciform Technique&amp;#34;.</a> Journal of Laparoendoscopy and Advanced Surgical Techiques A. 25 (8), 642-645 (2015).</li><li>Isaacs, A. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reducing+the+risks+of+proximal+and+distal+shunt+failure+in+adult+hydrocephalus:+A+shunt+outcomes+quality+improvement+study.">Reducing the risks of proximal and distal shunt failure in adult hydrocephalus: A shunt outcomes quality improvement study.</a> Journal of Neurosurgery. 136 (3), 877-886 (2022).</li><li>Relkin, N., Marmarou, A., Klinge, P., Bergsneider, M., Black, P. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Diagnosing+idiopathic+normal-pressure+hydrocephalus.">Diagnosing idiopathic normal-pressure hydrocephalus.</a> Neurosurgery. 57, 4-16 (2005).</li><li>Muram, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+standardized+infection+prevention+bundle+for+reduction+of+CSF+shunt+infections+in+adult+ventriculoperitoneal+shunt+surgery+performed+without+antibiotic-impregnated+catheters.">A standardized infection prevention bundle for reduction of CSF shunt infections in adult ventriculoperitoneal shunt surgery performed without antibiotic-impregnated catheters.</a> Journal of Neurosurgery. , 1-9 (2022).</li><li>Hamilton, M., Fung, A., Liam-Li, D., Isaacs, A., Conly, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+and+application+of+a+surgical+site+infection+prevention+bundle+for+shunt-related+insertions+and+revisions.">Development and application of a surgical site infection prevention bundle for shunt-related insertions and revisions.</a> Fluids and Barriers of the CNS. 15, (2018).</li></ol>

Patients tolerate the procedure well, are extubated immediately postop and are suitable for non-acute wards for overnight monitoring. It has been our practice to obtain a plain CT scan of the head the next morning to confirm the proximal catheter placement and as baseline imaging for future management. In addition, we obtain an abdominal x-ray to confirm the postoperative position of the abdominal catheter. The majority of our patients are assessed by both occupational therapy and physiotherapy and deemed safe by allied ...

Hydrocephalus, a common neurological disorder affecting approximately 175 per 100,000 adults worldwide1 is characterized by the accumulation of cerebrospinal fluid (CSF) within the cerebral ventricles due to an imbalance between CSF production and uptake processes in the brain2. As various non-surgical therapies have been unsuccessful3, the only viable treatment of hydrocephalus is the surgical diversion of the CSF from the cerebral ventricles. The most common approach utilized in adults is the placement of a shunt that drains the ventricular CSF into the peritoneal cavity (ventriculoperitoneal [VP] shunt)4,5.
A VP shunt has three subcutaneously located components: a proximal ventricular catheter inserted into a CSF ventricle through a skull burr hole, a valve to regulate the flow, and a distal catheter to connect the valve to the peritoneal cavity where the CSF is deposited and reabsorbed (Figure 1). Alternatively, a shunt can drain into the venous system at the level of the right atrium (ventriculoatrial [VA] shunt)6,7 or divert the spinal CSF from the spine into the peritoneal cavity (lumboperitoneal [LP] shunt)8. There is currently no evidence to support the superiority of VP versus VA versus LP shunt systems. In adults, 15%-25%9,10,11,12 of new VP shunts fail, typically within the first 6 months, and upward of 50% fail in high-risk populations13.VP shunt failure may be secondary to a shunt infection, valve malfunction, or catheter failure at the proximal or distal sites12,14,15,16,17. Each shunt failure requires repeat surgery, which is associated with a cumulative risk for perioperative complications18,19 and stress for patients and families, in addition to increased healthcare infrastructure costs20,21,22,23,24.
The &#34;traditional&#34; VP shunt insertion technique involves freehand insertion of the proximal catheter using surface anatomical landmarks and placement of the distal catheter either via a mini-laparotomy or a trocar conduit25,26,27. These techniques do not allow for real-time tracking or direct visualization of the final location during or after catheter insertion. Failure to achieve an ideal position for these catheters can lead to shunt failure, which is the most frequent long-term complication associated with VP shunt treatment of hydrocephalus10,28. Proximal catheters typically fail due to malposition and/or subsequent occlusion by the choroid plexus tissues or intraventricular debris. The leading causes of distal catheter failure in adults include catheter mispositioning, migration, and/or occlusion by omental tissues, bowel, and intrabdominal debris or adhesions11, 28,29,30,31.
There is recent evidence to suggest that the modification of VP shunt insertion techniques by placing the proximal and distal catheters under neuronavigation and laparoscopic guidance respectively, are associated with reduced risks of shunt failures26,32,33. In addition, compliance with shunt infection reduction protocols has been shown to reduce the risks of shunt failure secondary to infections34. Furthermore, Svoboda et al. described a &#34;falciform technique&#34; where the distal catheter was anchored to the falciform ligament and placed in the perihepatic space away from the omentum, which helped reduce the risk of catheter migration and obstruction by the omentum35. To our knowledge, while the use of neuronavigation and laparoscopy have been independently assessed, their combined benefits have not been reported, and the surgical techniques have not been adequately described in the literature.
We recently completed a 7 year prospective quality improvement study that combined neuronavigation, laparoscopy, the falciform technique and a shunt infection reduction protocol in adult hydrocephalus patients36. With our combined approach, the overall risk of shunt failure was reduced by 44%36. The objective of this paper is to present a surgical video accompanied by a step-by-step guide of the operative techniques to promote a paradigm shift toward the use of these adjuncts to reduce the risks of shunt failures in adults.
The surgical approach presented here can be performed for any VP shunt insertion surgery. We describe the case of a 72-year-old male who was diagnosed with idiopathic normal pressure hydrocephalus (iNPH) and met the criteria for a VP shunt insertion37. The patient presented with a 1 year history of progressive gait and cognitive impairment, with intermittent urinary incontinence. His past medical history was significant for hypertension and the surgical treatment of bladder cancer. A magnetic resonance imaging (MRI) brain evaluation of the patient showed ventriculomegaly with an Evan&#39;s index of 0.41. An MRI evaluation completed 4 years earlier did not demonstrate ventriculomegaly with an Evan&#39;s index of 0.29 (Figure 2). His neurological examination confirmed that he had a wide-based shuffling gait with low steppage and an abnormally slow gait velocity of 0.83 m/s. He had no signs of myelopathy. His Montreal Cognitive Assessment (MoCA) version 7.1 score was 22/30, which confirmed his mild-moderate cognitive impairment. After a 3 day external lumbar drain (ELD) trial with hourly CSF removal to test CSF removal symptom responsiveness, his gait velocity improved to 1.2 m/s and his MoCA score increased by 3 points.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>30-degree angle laparoscope&#160;</td>
			<td>Stryker</td>
			<td>0502-937-030</td>
			<td></td>
		</tr>
		<tr>
			<td>Barium impregnated proximal catheter&#160;</td>
			<td>Medtronic</td>
			<td>41101</td>
			<td></td>
		</tr>
		<tr>
			<td>Bowel grasper</td>
			<td>Richard Wolf</td>
			<td>8393.25</td>
			<td></td>
		</tr>
		<tr>
			<td>Certas Valve inline&#160;</td>
			<td>Codman</td>
			<td>82-8800</td>
			<td></td>
		</tr>
		<tr>
			<td>Chloraprep</td>
			<td>3M</td>
			<td>355-S10325/103.25</td>
			<td></td>
		</tr>
		<tr>
			<td>Electrocautery</td>
			<td>Karl Storz</td>
			<td>28160KA</td>
			<td></td>
		</tr>
		<tr>
			<td>Frameless-based neuronavigation system with magnetic tracking (AxiEM)</td>
			<td>Medtronic</td>
			<td>9735428/9734887</td>
			<td></td>
		</tr>
		<tr>
			<td>Hasson trocar&#160;</td>
			<td>Applied Medical Inc</td>
			<td>C0R95</td>
			<td></td>
		</tr>
		<tr>
			<td>Ioban</td>
			<td>3M</td>
			<td>6661EZ</td>
			<td></td>
		</tr>
		<tr>
			<td>Monocryl</td>
			<td>Ethicon</td>
			<td>D8550</td>
			<td></td>
		</tr>
		<tr>
			<td>Open barium impregnated proximal catheter&#160;</td>
			<td>Medtronic</td>
			<td>23092</td>
			<td></td>
		</tr>
		<tr>
			<td>Pneumatic surgical drill</td>
			<td>Medtronic</td>
			<td>PM100</td>
			<td></td>
		</tr>
		<tr>
			<td>Steri-Strips</td>
			<td>3M</td>
			<td>R1547</td>
			<td></td>
		</tr>
		<tr>
			<td>Video System Endoscopy</td>
			<td>Stryker</td>
			<td>Not Available</td>
			<td></td>
		</tr>
	</tbody>
</table>

neuronavigation and laparoscopy guided ventriculoperitoneal shunt insertion for the treatment of hydrocephalus

Hydrocephalus is a common adult neurosurgical condition typically requiring treatment with a cerebrospinal fluid (CSF) shunt, of which the ventriculoperitoneal (VP) shunt is the most common type. Unfortunately, the failure rates of VP shunts are alarmingly high, with up to 50% of patients requiring revision surgery within 2 years. VP shunt failure may occur due to infection, or catheter mispositioning, migration, and occlusion. We undertook a joint neurosurgery and general surgery collaboration in a 7-year prospective non-randomized consecutive quality improvement cohort study to reduce the rates of ventriculoperitoneal (VP) shunt failures in 224 adult patients at a tertiary care institution. The initiative combined the use of electromagnetic stereotactic neuronavigation to guide the placement of the proximal catheter and laparoscopy to place the distal catheter under direct visualization. With laparoscopic assistance, the distal catheter was anchored through a small hole created in the falciform ligament and placed into the right retrohepatic space, free from the omentum, adhesions, or bowel that might obstruct the catheter tip. The surgeries were performed using a shunt infection prevention protocol to reduce the risk of shunt infections. Here, we present an intraoperative video of the surgical procedure. Compliance with shunt infection reduction strategies and the combined utilization of neuronavigation and laparoscopy techniques in adult VP shunt surgery resulted in a 44% reduction in the risk of overall shunt failure. The significant positive impact with regard to shunt-failure-free patient outcomes among patients who underwent VP shunt surgery using this strategy underscores the value associated with the use of these modern intraoperative techniques and cross-specialty collaboration during VP shunt surgery.

On postoperative day #1, the patient presented in the video underwent a CT of the head and an x-ray of the abdomen (Figure 7). This imaging, respectively, demonstrated optimal proximal catheter placement in the right lateral ventricle and the location of the distal catheter in the peri-hepatic space. At the patient&#39;s 3-month and 1-year postoperative clinic assessments following placement of the VP shunt, his gait velocity had improved from a preoperative 0.83 m/s to 1.4 m/s and his MoCA ...

Watch this Scientific Journal Video about Neuronavigation and Laparoscopy Guided Ventriculoperitoneal Shunt Insertion for the Treatment of Hydrocephalus at JoVE.com

Neuronavigation and Laparoscopy Guided Ventriculoperitoneal Shunt Insertion for the Treatment of Hydrocephalus

Patient outcomes of ventriculoperitoneal (VP) shunt surgery, the mainstay treatment for hydrocephalus in adults, are poor due to high shunt failure rates. We present intraoperative footage of VP shunt insertion using neuronavigation and laparoscopy guidance, with the goal to reduce the risks of proximal and distal shunt catheter failures, respectively.

Hydrocephalus is a common adult neurosurgical condition typically requiring treatment with a cerebrospinal fluid (CSF) shunt, of which the ...

neuronavigation-laparoscopy-guided-ventriculoperitoneal-shunt

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JoVE Journal

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6.4K Views.  University of Calgary. Patient outcomes of ventriculoperitoneal (VP) shunt surgery, the mainstay treatment for hydrocephalus in adults, are poor due to high shunt failure rates. We present intraoperative footage of VP shunt insertion using neuronavigation and laparoscopy guidance, with the goal to reduce the risks of proximal and distal shunt catheter failures, respectively. 

Video: Neuronavigation and Laparoscopy Guided Ventriculoperitoneal Shunt Insertion for the Treatment of Hydrocephalus

The Measurement and Treatment of Suppression in Amblyopia

Amblyopia, a developmental disorder of the visual cortex, is one of the leading causes of visual dysfunction in the working age population. Current estimates put the prevalence of amblyopia at approximately 1-3%1-3, the majority of cases being monocular2. Amblyopia is most frequently caused by ocular misalignment (strabismus), blur induced by unequal refractive error (anisometropia), and in some cases by form deprivation.
Although amblyopia is initially caused by abnormal visual input in infancy, once established, the visual deficit often remains when normal visual input has been restored using surgery and/or refractive correction. This is because amblyopia is the result of abnormal visual cortex development rather than a problem with the amblyopic eye itself4,5 . Amblyopia is characterized by both monocular and binocular deficits6,7 which include impaired visual acuity and poor or absent stereopsis respectively. The visual dysfunction in amblyopia is often associated with a strong suppression of the inputs from the amblyopic eye under binocular viewing conditions8. Recent work has indicated that suppression may play a central role in both the monocular and binocular deficits associated with amblyopia9,10 .
Current clinical tests for suppression tend to verify the presence or absence of suppression rather than giving a quantitative measurement of the degree of suppression. Here we describe a technique for measuring amblyopic suppression with a compact, portable device11,12 . The device consists of a laptop computer connected to a pair of virtual reality goggles. The novelty of the technique lies in the way we present visual stimuli to measure suppression. Stimuli are shown to the amblyopic eye at high contrast while the contrast of the stimuli shown to the non-amblyopic eye are varied. Patients perform a simple signal/noise task that allows for a precise measurement of the strength of excitatory binocular interactions. The contrast offset at which neither eye has a performance advantage is a measure of the "balance point" and is a direct measure of suppression. This technique has been validated psychophysically both in control13,14 and patient6,9,11 populations.
In addition to measuring suppression this technique also forms the basis of a novel form of treatment to decrease suppression over time and improve binocular and often monocular function in adult patients with amblyopia12,15,16 . This new treatment approach can be deployed either on the goggle system described above or on a specially modified iPod touch device15.

Amblyopia is a developmental disorder of the visual cortex that is often accompanied by strong suppression of one eye. We present a new technique for measuring and treating interocular suppression in patients with amblyopia that can be deployed using virtual reality goggles or a portable iPod Touch device.

Amblyopia, a developmental disorder of the visual cortex, is one of the leading causes of visual dysfunction in the working age population. Current ...

The Goeckerman Regimen for the Treatment of Moderate to Severe Psoriasis

Psoriasis is a chronic, immune-mediated inflammatory skin disease affecting approximately 2-3% of the population. The Goeckerman regimen consists of exposure to ultraviolet B (UVB) light and application of crude coal tar (CCT). Goeckerman therapy is extremely effective and relatively safe for the treatment of psoriasis and for improving a patient's quality of life. In the following article, we present our protocol for the Goeckerman therapy that is utilized specifically at the University of California, San Francisco. This protocol details the preparation of supplies, administration of phototherapy and application of topical tar. This protocol also describes how to assess the patient daily, monitor for adverse effects (including pruritus and burning), and adjust the treatment based on the patient's response. Though it is one of the oldest therapies available for psoriasis, there is an absence of any published videos demonstrating the process in detail. The video is beneficial for healthcare providers who want to administer the therapy, for trainees who want to learn more about the process, and for prospective patients who want to undergo treatment for their cutaneous disease.

Psoriasis is a chronic, immune-mediated inflammatory skin disease. The Goeckerman regimen, formulated for the treatment of psoriasis, consists of exposure to ultraviolet B (UVB) light and application of crude coal tar (CCT). The following protocol is for the administration of Goeckerman therapy for the treatment of moderate-to-severe psoriasis.

Psoriasis is a  chronic, immune-mediated inflammatory skin disease affecting approximately 2-3%  of the population. The Goeckerman regimen consists of ...

3D-Neuronavigation In Vivo Through a Patient's Brain During a Spontaneous Migraine Headache

A growing body of research, generated primarily from MRI-based studies, shows that migraine appears to occur, and possibly endure, due to the alteration of specific neural processes in the central nervous system. However, information is lacking on the molecular impact of these changes, especially on the endogenous opioid system during migraine headaches, and neuronavigation through these changes has never been done. This study aimed to investigate, using a novel 3D immersive and interactive neuronavigation (3D-IIN) approach, the endogenous &#181;-opioid transmission in the brain during a migraine headache attack in vivo. This is arguably one of the most central neuromechanisms associated with pain regulation, affecting multiple elements of the pain experience and analgesia. A 36 year-old female, who has been suffering with migraine for 10 years, was scanned in the typical headache (ictal) and nonheadache (interictal) migraine phases using Positron Emission Tomography (PET) with the selective radiotracer [11C]carfentanil, which allowed us to measure &#181;-opioid receptor availability in the brain (non-displaceable binding potential - &#181;OR BPND). The short-life radiotracer was produced by a cyclotron and chemical synthesis apparatus on campus located in close proximity to the imaging facility. Both PET scans, interictal and ictal, were scheduled during separate mid-late follicular phases of the patient's menstrual cycle. During the ictal PET session her spontaneous headache attack reached severe intensity levels; progressing to nausea and vomiting at the end of the scan session. There were reductions in &#181;OR BPND in the pain-modulatory regions of the endogenous &#181;-opioid system during the ictal phase, including the cingulate cortex, nucleus accumbens (NAcc), thalamus (Thal), and periaqueductal gray matter (PAG); indicating that &#181;ORs were already occupied by endogenous opioids released in response to the ongoing pain. To our knowledge, this is the first time that changes in &#181;OR BPND during a migraine headache attack have been neuronavigated using a novel 3D approach. This method allows for interactive research and educational exploration of a migraine attack in an actual patient's neuroimaging dataset.

3D-Neuronavigation In Vivo Through a Patient&#039;s Brain During a Spontaneous Migraine Headache

In this study, the authors report for the first time a novel 3D-Immersive &#38; Interactive Neuronavigation (3D-IIN) through the impact of a spontaneous migraine headache attack in the &#956;-opioid system of a patient's brain in vivo.

A growing body of research, generated primarily from MRI-based studies, shows that migraine appears to occur, and possibly endure, due to the alteration ...

The Rabbit Blood-shunt Model for the Study of Acute and Late Sequelae of Subarachnoid Hemorrhage: Technical Aspects

Early brain injury and delayed cerebral vasospasm both contribute to unfavorable outcomes after subarachnoid hemorrhage (SAH). Reproducible and controllable animal models that simulate both conditions are presently uncommon. Therefore, new models are needed in order to mimic human pathophysiological conditions resulting from SAH.
This report describes the technical nuances of a rabbit blood-shunt SAH model that enables control of intracerebral pressure (ICP). An extracorporeal shunt is placed between the arterial system and the subarachnoid space, which enables examiner-independent SAH in a closed cranium. Step-by-step procedural instructions and necessary equipment are described, as well as technical considerations to produce the model with minimal mortality and morbidity. Important details required for successful surgical creation of this robust, simple and consistent ICP-controlled SAH rabbit model are described.

The experimental intracranial pressure-controlled blood shunt subarachnoid hemorrhage (SAH) model in the rabbit combines the standard procedures &#8212; subclavian artery cannulation and transcutaneous cisterna magna puncture, which enables close mimicking of human pathophysiological conditions after SAH. We present step-by-step instructions and discuss key surgical points for successful experimental SAH creation.

Early brain injury and delayed cerebral vasospasm both contribute to unfavorable outcomes after subarachnoid hemorrhage (SAH). Reproducible and ...

MRI-guided dmPFC-rTMS as a Treatment for Treatment-resistant Major Depressive Disorder

Here we outline the protocol for magnetic resonance imaging (MRI) guided repetitive transcranial magnetic stimulation (rTMS) to the dorsal medial prefrontal cortex (dmPFC) in patients with major depressive disorder (MDD). Technicians used a neuronavigation system to process patient MRIs to generate a 3-dimensional head model. The head model was subsequently used to identify patient-specific stimulatory targets. The dmPFC was stimulated daily for 20 sessions. Stimulation intensity was titrated to address scalp pain associated with rTMS. Weekly assessments were conducted on the patients using the Hamilton Rating Scale for Depression (HamD17) and Beck Depression Index II (BDI-II). Treatment-resistant MDD patients achieved significant improvements on both HAMD and BDI-II. Of note, angled, double-cone coil rTMS at 120% resting motor threshold allows for optimal stimulation of deeper midline prefrontal regions, which results in a possible therapeutic application for MDD. One major limitation of the rTMS field is the heterogeneity of treatment parameters across studies, including duty cycle, number of pulses per session and intensity. Further work should be done to clarify the effect of stimulation parameters on outcome. Future dmPFC-rTMS work should include sham-controlled studies to confirm its clinical efficacy in MDD.

Here we outline the procedure for MRI-guided repetitive transcranial magnetic stimulation to the dorsomedial prefrontal cortex as an experimental treatment for major depressive disorder.

Here we outline the protocol for magnetic resonance imaging (MRI) guided repetitive transcranial magnetic stimulation (rTMS) to the dorsal medial ...

Network Analysis of Foramen Ovale Electrode Recordings in Drug-resistant Temporal Lobe Epilepsy Patients

Approximately 30% of epilepsy patients are refractory to antiepileptic drugs. In these cases, surgery is the only alternative to eliminate/control seizures. However, a significant minority of patients continues to exhibit post-operative seizures, even in those cases in which the suspected source of seizures has been correctly localized and resected. The protocol presented here combines a clinical procedure routinely employed during the pre-operative evaluation of temporal lobe epilepsy (TLE) patients with a novel technique for network analysis. The method allows for the evaluation of the temporal evolution of mesial network parameters. The bilateral insertion of foramen ovale electrodes (FOE) into the ambient cistern simultaneously records electrocortical activity at several mesial areas in the temporal lobe. Furthermore, network methodology applied to the recorded time series tracks the temporal evolution of the mesial networks both interictally and during the seizures. In this way, the presented protocol offers a unique way to visualize and quantify measures that considers the relationships between several mesial areas instead of a single area.

This protocol describes a procedure to track the evolution of mesial network measures in temporal lobe epilepsy (TLE) patients. It is based on the combination of intracranial recordings with a novel numerical technique for data analysis. Specifically, we present a protocol for network analyses of foramen ovale recordings.

Approximately 30% of epilepsy patients are refractory to antiepileptic drugs. In these cases, surgery is the only alternative to eliminate/control ...

Transvaginal Mesh Insertion in the Ovine Model

This protocol describes mesh insertion into the rectovaginal septum in sheep using a single vaginal incision technique, with and without the trocar-guided insertion of anchoring arms. Parous sheep underwent the dissection of the rectovaginal septum, followed by the insertion of an implant with or without four anchoring arms, both designed to fit the ovine anatomy. The anchoring arms were put in place using a trocar and an "outside-in" technique. The cranial arms were passed through the obturator, gracilis, and adductor magnus muscles. The caudal arms were fixed near the sacrotuberous ligament, through the coccygeus muscles. This technique allows for the mimicking of surgical procedures performed in women suffering from pelvic organ prolapse. The anatomical spaces and elements are easily identified. The most critical part of the procedure is the insertion of the cranial trocar, which can easily penetrate the peritoneal cavity or the surrounding pelvic organs. This can be avoided by a more extensive retroperitoneal dissection and by guiding the trocar more laterally. This approach is designed only for experimental testing of novel implants in large animal models, as trocar-guided insertion is currently not used clinically.

This protocol describes mesh implantation in the ovine rectovaginal septum using a single vaginal incision technique, with and without the trocar-guided insertion of anchoring arms.

This protocol describes mesh insertion into the rectovaginal septum in sheep using a single vaginal incision technique, with and without the trocar-guided ...

Predicting Treatment Response to Image-Guided Therapies Using Machine Learning: An Example for Trans-Arterial Treatment of Hepatocellular Carcinoma

Intra-arterial therapies are the standard of care for patients with hepatocellular carcinoma who cannot undergo surgical resection. The objective of this study was to develop a method to predict response to intra-arterial treatment prior to intervention.
The method provides a general framework for predicting outcomes prior to intra-arterial therapy. It involves pooling clinical, demographic and imaging data across a cohort of patients and using these data to train a machine learning model. The trained model is applied to new patients in order to predict their likelihood of response to intra-arterial therapy.
The method entails the acquisition and parsing of clinical, demographic and imaging data from N patients who have already undergone trans-arterial therapies. These data are parsed into discrete features (age, sex, cirrhosis, degree of tumor enhancement, etc.) and binarized into true/false values (e.g., age over 60, male gender, tumor enhancement beyond a set threshold, etc.). Low-variance features and features with low univariate associations with the outcome are removed. Each treated patient is labeled according to whether they responded or did not respond to treatment. Each training patient is thus represented by a set of binary features and an outcome label. Machine learning models are trained using N - 1 patients with testing on the left-out patient. This process is repeated for each of the N patients. The N models are averaged to arrive at a final model.
The technique is extensible and enables inclusion of additional features in the future. It is also a generalizable process that may be applied to clinical research questions outside of interventional radiology. The main limitation is the need to derive features manually from each patient. A popular modern form of machine learning called deep learning does not suffer from this limitation, but requires larger datasets.

Intra-arterial therapies are the standard of care for patients with hepatocellular carcinoma who cannot undergo surgical resection. A method for predicting response to these therapies is proposed. The technique uses pre-procedural clinical, demographic, and imaging information to train machine learning models capable of predicting response prior to treatment.

Intra-arterial therapies are the standard of care for patients with hepatocellular carcinoma who cannot undergo surgical resection. The objective of this ...

Transaxillary First Rib Resection for Treatment of the Thoracic Outlet Syndrome

Thoracic outlet syndrome (TOS) is a common disorder that causes a significant loss of productivity. The transaxillary first rib resection (TFRR) protocol has been used for the decompression of trapped neurovascular structures in the TOS. Among the other surgical procedures, the advantage of the TFRR is that it has the smallest rate of recurrence and better cosmetic outcomes. The disadvantage of TFRR is that it provides a narrow, and deep working corridor that makes obtaining vascular control challenging.

Here, we present a protocol of the transaxillary resection of the first rib for treatment of thoracic outlet syndrome caused by compression of the brachial plexus, subclavian vein and artery.

Thoracic outlet syndrome (TOS) is a common disorder that causes a significant loss of productivity. The transaxillary first rib resection (TFRR) protocol ...

Laparoscopy-endoscopy Cooperative Surgery for the Treatment of Gastric Gastrointestinal Stromal Tumors

In view of the shortcomings of endoscopic or laparoscopic surgeries alone in the treatment of gastric gastrointestinal stromal tumors (G-GISTs), this approach makes an innovative improvement in the treatment of G-GISTs that are less than 5 cm in size. Laparoscopy-endoscopy cooperative surgery (LECS) is used to combine endoscopic and laparoscopic surgeries, fully realizing their respective advantages and avoiding their drawbacks. The main steps are as follows. First, gastroscopy and laparoscopy are combined to confirm the location and boundary of the tumor. Tumor resection is carried out laparoscopically, guided by a gastroscope. The specimen is removed orally and the gastric wound closed laparoscopically. Then, gastroscopy and laparoscopy are combined to determine whether there is wound bleeding, if the suture is satisfactory, and if the gastric cavity is deformed.
LECS has natural advantages in the treatment of G-GISTs that are less than 5 cm in size. The accurate estimation of tumor location and boundary greatly improves the complete resection rate of tumors. The risk of tumor rupture is substantially reduced, and the long-term prognosis of patients is significantly improved. The process allows for accurate resection of the tumor, maximum preservation of normal gastric tissue and organ function, and avoids postoperative gastric deformation. The patient's postoperative rehabilitation is greatly accelerated, and oral feeding can resume on the day of the operation. The specimen is taken out through the mouth to avoid the need for an extended abdominal incision. This greatly reduces the patient's postoperative pain and scarring. The method greatly shortens the postoperative hospital stay (i.e., discharge is possible on the day after the operation), increasing the turnover of hospital beds.

Laparoscopy-endoscopy cooperative surgery is appropriate for the treatment of gastric gastrointestinal stromal tumors less than 5 cm in size. It can achieve the respective advantages of endoscopic and laparoscopic surgeries while avoiding their drawbacks.

In view of the shortcomings of endoscopic or laparoscopic surgeries alone in the treatment of gastric gastrointestinal stromal tumors (G-GISTs), this ...