1. Case Presentation
<ol>
	<li>The patient is set up for a visit at the gynecological clinic, often due to the occurrence of bleeding disorders. A physical examination is performed.
	<ol>
		<li>If deemed appropriate, the patient is scheduled for a hysterectomy. The paperwork is prepared, and the patient is given the premedication for the day of surgery.</li>
		<li>Patients 60 years and older must first submit blood samples and monitored by electrocardiography (or ECG) prior to the procedure.</li>
	</ol>
	</li>
	<li>On the day of surgery, the patient is not allowed to consume anything by mouth for six hours prior to admittance.
	<ol>
		<li>An exception is made for sweet clear drinks without pulp, which are allowed until two hours prior to admittance.</li>
		<li>The patient takes the premedication (t.Paracetemol 1 g + t.Etodolac 300 mg + t.Dexamethason 8 mg) with the last drink.</li>
	</ol>
	</li>
	<li>The patient is admitted app. one hour prior to the scheduled time of surgery.
	<ol>
		<li>The ward nurse first prepares the patient for surgery.</li>
		<li>The anesthesiologist examines the patient and prepares the papers for anesthesia.</li>
	</ol>
	</li>
	<li>When the operation room is prepared and the team is ready, the gynecologist transports the patient to the operating room.
	<ol>
		<li>The patient lies down on the operating table and is covered with a surgical blanket.</li>
		<li>An i.v. line is placed in the left hand and 1,000 ml of saline is started. Monitoring equipment is attached.</li>
		<li>Anesthesia is induced with propofol and remifentanil until Loss Of Consciousness (LOC) occurs, and maintained using TOF.</li>
		<li>For facilitating intubation, a small dose of rocuronium (15 mg) is administered.</li>
		<li>Direct laryngoscopy is performed. If it is difficult to visualize the vocal cord, the McGrath videolaryngoscop is used. Intubation is subsequently performed.</li>
	</ol>
	</li>
	<li>Insufflation of the abdomen is started at 12 mm Hg CO2.
	<ol>
		<li>The ports are placed.</li>
		<li>The procedure is started.</li>
		<li>The surgeons are told when Train Of Four (TOF) ratio is &gt; 90%, corresponding to the neuromuscular blockade is weaned off.</li>
		<li>At the neck of the grasper the distance from the promontory to the surface of the skin at the umbilicus is marked.</li>
		<li>The grasper is placed on the surgical table. With measuring tape, the distance between the end of the grasper and the neck of the grasper (at surgeon's finger) is marked, and then calculated distance is measured in centimeters.</li>
	</ol>
	</li>
	<li>The insufflations pressure of CO2 is lowered to 8 mm Hg.
	<ol>
		<li>At the neck of the grasper the distance from the promontory to the surface of the skin at the umbilicus is marked.</li>
		<li>The grasper is placed at the table. With measuring tape the marked distance is interpreted to centimeters.</li>
	</ol>
	</li>
	<li>CO2 insufflation pressure is adjusted to 12 mm Hg.
	<ol>
		<li>Deep neuromuscular blockade is applied to a Post Tetanic Count (PTC) &lt; 2.</li>
		<li>At the neck of the grasper the distance from the promontory to the surface of the skin at the umbilicus is marked.</li>
		<li>The grasper is placed at the table. With measuring tape the marked distance is measured to centimeters.</li>
	</ol>
	</li>
	<li>CO2 insufflation pressure is lowered to 8 mm Hg.
	<ol>
		<li>At the neck of the grasper the distance from the promontory to the surface of the skin at the umbilicus is marked.</li>
		<li>At the neck of the grasper the distance from the promontory to the surface of the skin at the umbilicus is marked.</li>
	</ol>
	</li>
	<li>The procedure is finished.
	<ol>
		<li>Infusions of propofol and remifentanil are terminated.</li>
		<li>The patient is woken up and moved to his or her bed.</li>
		<li>The patient is transferred to the Recovery Room.</li>
	</ol>
	</li>
</ol>

<ol>
	<li>Jones, R. K., Caldwell, J. E., Sorin, C. B., Brull, J., Soto, R. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reversal+of+Profound+Rocuronium-induced+Blockade+with+Sugammadex.">Reversal of Profound Rocuronium-induced Blockade with Sugammadex.</a> Anesthesiology. 109, 816-824 (2008).</li><li>Berg, H., Roed, J., Viby-Mogensen, J., Mortensen, C. R., Enfbaek, J., Skovgaard, L. T., Krintel, J. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Residual+neuromuscular+block+is+a+risk+factor+for+post-operative+pulmonary+complications:+A+prospective,+randomized,+and+blinded+study+of+postoperative+pulmonary+complications+after+atracurium,+vecuronium+and+pancuronium.">Residual neuromuscular block is a risk factor for post-operative pulmonary complications: A prospective, randomized, and blinded study of postoperative pulmonary complications after atracurium, vecuronium and pancuronium.</a> Acta Anaesthesiol. Scand. 41, 1095-1103 (1997).</li><li>Abrishami, A., Ho, J., Wong, J., Yin, L., Chung, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sugammadex,+a+selective+reversal+medication+for+preventing+postoperative+residual+neuromuscular+blockade.">Sugammadex, a selective reversal medication for preventing postoperative residual neuromuscular blockade.</a> The Cochrane Collaborations. , (2009).</li><li>Plaud, B., Debaene, B., Donati, F., Marty, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Residual+Paralysis+after+Emergence+from+Anesthesia.">Residual Paralysis after Emergence from Anesthesia.</a> Anesthesiology. 112, 1013-1022 (2010).</li><li>Lee, D. W., Kim, M. J., Lee, Y. K., Lee, H. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Does+Intraabdominal+Pressure+Affect+Development+of+Subcutaneous+Emphysema+at+Gynecologic+Laparoscopy?.">Does Intraabdominal Pressure Affect Development of Subcutaneous Emphysema at Gynecologic Laparoscopy?.</a> Minimally Invasive Gynecology. , 761-765 (2011).</li><li>Sandhu, T., Yamada, S., Ariyakachon, V., Chakrabandhu, T., Chongruksut, W., Ko-iam, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Low-pressure+pneumoperitoneum+versus+standard+pneumoperitoneum+in+laparoscopic+cholecystectomy,+a+prospective+randomized+clinical+trial.">Low-pressure pneumoperitoneum versus standard pneumoperitoneum in laparoscopic cholecystectomy, a prospective randomized clinical trial.</a> Surg. Endosc. 23, 1044-1047 (2009).</li><li>Sarli, L., Coisti, R., Sansebastiano, G., Trivelli, M., Roncoroni, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Prospective+randomized+trial+of+low-pressure+pneumoperitoneum+for+reduction+of+shoulder-tip+pain+following+laparoscopy.">Prospective randomized trial of low-pressure pneumoperitoneum for reduction of shoulder-tip pain following laparoscopy.</a> British Journal of Surgery. 87, 1161-1165 (2000).</li><li>Kandil, T. S., El Hefnawy, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Shoulder+pain+following+laparoscopic+cholecystectomy:+factors+affecting+the+incidence+and+severity.">Shoulder pain following laparoscopic cholecystectomy: factors affecting the incidence and severity.</a> J. Laparoendosc. Adv. Surg. Tech. A. 8, 677-682 (2010).</li><li>Mulier, J. P., Dillemans, B. R. S., Crombach, M., Missant, C., Sels, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=On+the+abdominal+pressure+volume+relationship.">On the abdominal pressure volume relationship.</a> The internet Journal of Anesthesiology. 21, (2009).</li><li>Srvastava, A., Niranjan, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Secrets+of+safe+laparoscopic+surgery:+Anaesthetic+and+surgical+considerations.">Secrets of safe laparoscopic surgery: Anaesthetic and surgical considerations.</a> J. Minim. Access. Surg. 6, 91-94 (2010).</li><li>Grosse-Sundrup, M., Henneman, J. P., Sandberg, W. S., Bateman, B. T., Uribe, J. V., Nguyen, N. T., 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=Intermediate+acting+non-depolarizing+neuromuscular+blocking+agents+and+risk+of+postoperative+respiratory+complications:+prospective+propensity+score+matched+cohort+study.">Intermediate acting non-depolarizing neuromuscular blocking agents and risk of postoperative respiratory complications: prospective propensity score matched cohort study.</a> BMJ. 345, e6329 (2012).</li><li>Kaneko, G., Miyajima, A., Yazawa, S., Yuge, K., Kikuchi, E., Asanuma, H., Nakagawa, K., Oya, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=What+is+the+predictor+of+prolonged+operative+time+during+laparoscopic+radical+prostatectomy?.">What is the predictor of prolonged operative time during laparoscopic radical prostatectomy?.</a> Int. J. Urol. 20 (3), 330-336 (2012).</li><li>Drahonovsky, J., Haakova, L., Otcenasek, M., Krofta, L., Kucera, E., Feyereisl, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+prospective+randomized+comparison+of+vaginal+hysterectomy,+laparoscopically+assisted+vaginal+hysterectomy,+and+total+laparoscopic+hysterectomy+in+women+with+benign+uterine+disease.">A prospective randomized comparison of vaginal hysterectomy, laparoscopically assisted vaginal hysterectomy, and total laparoscopic hysterectomy in women with benign uterine disease.</a> Eur. J. Obstet. Gynecol. Reprod. Biol. 148 (2), 172-176 (2010).</li></ol>

No conflicts of interest declared.

Directly calculating the working volume available for laproscopic surgery is difficult, but the relationship between insufflating CO2 pressure and abdominal volume is easier to measure9. Here, we present a method to use the surgical grasper to estimate the space within the abdomen during insufflation, as an alternative to the method of recording the volume of insufflated CO2. These measurements have demonstrated that it is possible to maintain a steady volume when loweri...

Neuromuscular blocking agents are commonly used to facilitate tracheal intubation, and, during anesthesia, to facilitate surgery. The use of pharmacological agents to achieve deep relaxation throughout the laparoscopic procedure allows the surgeons either to proceed at the same level of CO2 insufflation while benefitting from better surgical conditions, or lowering the insufflating pressure to lower the risk of surgical complications. Several studies have shown the positive effect of lowering the working pressure 5,6,7. One symptom that is often seen after laparoscopic hysterectomies is shoulder pain, which is often stated as a major problem and the most important issue when speaking to the patient at follow up.8
Laproscopic myomectomy or hysterectomy is usually recommended when more conservative methods fail to control the symptoms caused by uterine fibroids. At our institution, these procedures are performed at an insufflating CO2 pressure of 12 mm Hg. There are two highly experienced gynecologists performing all the gynecologic cases. All our cases are anaesthetized with propofol and remifentanil, and intubation is often facilitated with a low dose of rocuronium (15 mg).
From our daily clinical work we have identified shoulder pain as one of the most disturbing side effects after laparoscopic hysterectomies, which is supported by the literature 8. Studies have shown that reducing the intraabdominal pressure can also reduce shoulder pain. In an effort to reduce the CO2 insufflation pressure, one of our prior concerns was if the surgical field and visibility during the procedure would be compromised. Trying to determine the overview during the procedure, we set up a method to compare the intraabdominal working space. However, it can be very difficult to monitor the exact intra-abdominal volume within a patient during surgery. In a Belgian study, the volume-pressure relationship has been described, but the study authors concluded that there are major inter individual variations 9. In order to get a more reliable statement of the intraabdominal space, we use the distance from the promontory to the skin as the metric.

deep neuromuscular blockade leads to a larger intraabdominal volume during laparoscopy

Shoulder pain is a commonly reported symptom following laparoscopic procedures such as myomectomy or hysterectomy, and recent studies have shown that lowering the insufflation pressure during surgery may reduce the risk of post-operative pain. In this pilot study, a method is presented for measuring the intra-abdominal space available to the surgeon during laproscopy, in order to examine whether the relaxation produced by deep neuromuscular blockade can increase the working surgical space sufficiently to permit a reduction in the CO2 insufflation pressure. Using the laproscopic grasper, the distance from the promontory to the skin is measured at two different insufflation pressures: 8 mm Hg and 12 mm Hg. After the initial measurements, a neuromuscular blocking agent (rocuronium) is administered to the patient and the intra-abdominal volume is measured again. Pilot data collected from 15 patients shows that the intra-abdominal space at 8 mm Hg with blockade is comparable to the intra-abdominal space measured at 12 mm Hg without blockade. The impact of neuromuscular blockade was not correlated with patient height, weight, BMI, and age. Thus, using neuromuscular blockade to maintain a steady volume while reducing insufflation pressure may produce improved patient outcomes.

This pilot study of 15 patients was performed to assess the impact of deep neuromuscular blockade during laparoscopic surgery.
The method illustrated here was used to obtain measurements of intra-abdominal space in patients undergoing laparoscopic hysterectomy (Figure 1). In each patient, measurements of intra-abdominal space were taken under the following conditions: 12 mm Hg pressure without deep neuromuscular blockade, 12 mm Hg with blockade, 8 mm Hg without blockade, and ...

Watch this Scientific Journal Video about Deep Neuromuscular Blockade Leads to a Larger Intraabdominal Volume During Laparoscopy at JoVE.com

Deep Neuromuscular Blockade Leads to a Larger Intraabdominal Volume During Laparoscopy

This article presents a method for measuring the working abdominal volume during laproscopic myomectomy using the surgical grasper, and applies this technique to obtain pilot data on whether deep neuromuscular blockade (NMB) can enable the use of lower insufflation pressure. Reduced insufflation pressure during laproscopic surgery has been shown to reduce post-operative pain, and thus the use of NMB during surgery may enable improved patient outcomes.

Shoulder pain is a commonly reported symptom following laparoscopic procedures such as myomectomy or hysterectomy, and recent studies have shown that ...

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13.1K Views.  Aleris-Hamlet Hospitals, Soeborg, Denmark.  This article presents a method for measuring the working abdominal volume during laproscopic myomectomy using the surgical grasper, and applies this technique to obtain pilot data on whether deep neuromuscular blockade (NMB) can enable the use of lower insufflation pressure. Reduced insufflation pressure during laproscopic surgery has been shown to reduce post-operative pain, and thus the use of NMB during surgery may enable improved patient outcomes. 

Video: Deep Neuromuscular Blockade Leads to a Larger Intraabdominal Volume During Laparoscopy

Dorsal Column Steerability with Dual Parallel Leads using Dedicated Power Sources:  A Computational Model

In spinal cord stimulation (SCS), concordance of stimulation-induced paresthesia over painful body regions is a necessary condition for therapeutic efficacy. Since patient pain patterns can be unique, a common stimulation configuration is the placement of two leads in parallel in the dorsal epidural space. This construct provides flexibility in steering stimulation current mediolaterally over the dorsal column to achieve better pain-paresthesia overlap. Using a mathematical model with an accurate fiber diameter distribution, we studied the ability of dual parallel leads to steer stimulation between adjacent contacts on dual parallel leads using (1) a single source system, and (2) a multi-source system, with a dedicated current source for each contact. The volume conductor model of a low-thoracic spinal cord with epidurally-positioned dual parallel (2 mm separation) percutaneous leads was first created, and the electric field was calculated using ANSYS, a finite element modeling tool. The activating function for 10 um fibers was computed as the second difference of the extracellular potential along the nodes of Ranvier on the nerve fibers in the dorsal column. The volume of activation (VOA) and the central point of the VOA were computed using a predetermined threshold of the activating function. The model compared the field steering results with single source versus dedicated power source systems on dual 8-contact stimulation leads. The model predicted that the multi-source system can target more central points of stimulation on the dorsal column than a single source system (100 vs. 3) and the mean steering step for mediolateral steering is 0.02 mm for multi-source systems vs 1 mm for single source systems, a 50-fold improvement. The ability to center stimulation regions in the dorsal column with high resolution may allow for better optimization of paresthesia-pain overlap in patients.

Using a mathematical model of spinal cord stimulation, we found that a multi-source system with independent power sources for each contact can target more central points of stimulation on the dorsal column (100 vs 3) and has 50-fold more field steering resolution (0.02mm vs 1mm) than a single-source system.

In spinal cord stimulation (SCS), concordance of stimulation-induced paresthesia over painful body regions is a necessary condition for therapeutic ...

Utilizing Transcranial Magnetic Stimulation to Study the Human Neuromuscular System

Transcranial magnetic stimulation (TMS) has been in use for more than 20 years 1, and has grown exponentially in popularity over the past decade. While the use of TMS has expanded to the study of many systems and processes during this time, the original application and perhaps one of the most common uses of TMS involves studying the physiology, plasticity and function of the human neuromuscular system. Single pulse TMS applied to the motor cortex excites pyramidal neurons transsynaptically 2 (Figure 1) and results in a measurable electromyographic response that can be used to study and evaluate the integrity and excitability of the corticospinal tract in humans 3. Additionally, recent advances in magnetic stimulation now allows for partitioning of cortical versus spinal excitability 4,5. For example, paired-pulse TMS can be used to assess intracortical facilitatory and inhibitory properties by combining a conditioning stimulus and a test stimulus at different interstimulus intervals 3,4,6-8. In this video article we will demonstrate the methodological and technical aspects of these techniques. Specifically, we will demonstrate single-pulse and paired-pulse TMS techniques as applied to the flexor carpi radialis (FCR) muscle as well as the erector spinae (ES) musculature. Our laboratory studies the FCR muscle as it is of interest to our research on the effects of wrist-hand cast immobilization on reduced muscle performance6,9, and we study the ES muscles due to these muscles clinical relevance as it relates to low back pain8. With this stated, we should note that TMS has been used to study many muscles of the hand, arm and legs, and should iterate that our demonstrations in the FCR and ES muscle groups are only selected examples of TMS being used to study the human neuromuscular system.

Transcranial magnetic stimulation (TMS) is a non-invasive tool to gain insight on the physiology and function of the human nervous system. Here, we present our TMS techniques to study cortical excitability of the upper limb and lumbar musculature.

Transcranial magnetic stimulation (TMS) has been in use for more than 20 years 1, and has grown exponentially in popularity over the past decade.  While ...

A Murine Model of Muscle Training by Neuromuscular Electrical Stimulation

Neuromuscular electrical stimulation (NMES) is a common clinical modality that is widely used to restore1, maintain2 or enhance3-5 muscle functional capacity. Transcutaneous surface stimulation of skeletal muscle involves a current flow between a cathode and an anode, thereby inducing excitement of the motor unit and the surrounding muscle fibers. 
NMES is an attractive modality to evaluate skeletal muscle adaptive responses for several reasons. First, it provides a reproducible experimental model in which physiological adaptations, such as myofiber hypertophy and muscle strengthening6, angiogenesis7-9, growth factor secretion9-11, and muscle precursor cell activation12 are well documented. Such physiological responses may be carefully titrated using different parameters of stimulation (for Cochrane review, see 13). In addition, NMES recruits motor units non-selectively, and in a spatially fixed and temporally synchronous manner14, offering the advantage of exerting a treatment effect on all fibers, regardless of fiber type. Although there are specified contraindications to NMES in clinical populations, including peripheral venous disorders or malignancy, for example, NMES is safe and feasible, even for those who are ill and/or bedridden and for populations in which rigorous exercise may be challenging. 
Here, we demonstrate the protocol for adapting commercially available electrodes and performing a NMES protocol using a murine model. This animal model has the advantage of utilizing a clinically available device and providing instant feedback regarding positioning of the electrode to elicit the desired muscle contractile effect. For the purpose of this manuscript, we will describe the protocol for muscle stimulation of the anterior compartment muscles of a mouse hindlimb.

A murine model of neuromuscular electrical stimulation (NMES), a safe and inexpensive clinical modality, to the anterior compartment muscles is described. This model has the advantage of modifying a readily available clinical device for the purpose of eliciting targeted and specific muscle contractions in mice.

Neuromuscular electrical stimulation (NMES) is a common clinical modality that is widely used to restore1, maintain2 or enhance3-5 muscle functional ...

Construction of Vapor Chambers Used to Expose Mice to Alcohol During the Equivalent of all Three Trimesters of Human Development

Exposure to alcohol during development can result in a constellation of morphological and behavioral abnormalities that are collectively known as Fetal Alcohol Spectrum Disorders (FASDs). At the most severe end of the spectrum is Fetal Alcohol Syndrome (FAS), characterized by growth retardation, craniofacial dysmorphology, and neurobehavioral deficits. Studies with animal models, including rodents, have elucidated many molecular and cellular mechanisms involved in the pathophysiology of FASDs. Ethanol administration to pregnant rodents has been used to model human exposure during the first and second trimesters of pregnancy. Third trimester ethanol consumption in humans has been modeled using neonatal rodents. However, few rodent studies have characterized the effect of ethanol exposure during the equivalent to all three trimesters of human pregnancy, a pattern of exposure that is common in pregnant women. Here, we show how to build vapor chambers from readily obtainable materials that can each accommodate up to six standard mouse cages. We describe a vapor chamber paradigm that can be used to model exposure to ethanol, with minimal handling, during all three trimesters. Our studies demonstrate that pregnant dams developed significant metabolic tolerance to ethanol. However, neonatal mice did not develop metabolic tolerance and the number of fetuses, fetus weight, placenta weight, number of pups/litter, number of dead pups/litter, and pup weight were not significantly affected by ethanol exposure. An important advantage of this paradigm is its applicability to studies with genetically-modified mice. Additionally, this paradigm minimizes handling of animals, a major confound in fetal alcohol research.

We demonstrate the construction of alcohol vapor chambers using readily available materials that simultaneously house 6 mouse cages. We further describe their use in a mouse model of fetal alcohol exposure equivalent to all 3&#160;trimesters of human pregnancy. This paradigm exposes animals during gestation and postnatal days 1-12.

Exposure to alcohol during development can result in a constellation of morphological and behavioral abnormalities that are collectively known as Fetal ...

Clinical Assessment of Spatiotemporal Gait Parameters in Patients and Older Adults

Spatial and temporal characteristics of human walking are frequently evaluated to identify possible gait impairments, mainly in orthopedic and neurological patients1-4, but also in healthy older adults5,6. The quantitative gait analysis described in this protocol is performed with a recently-introduced photoelectric system (see&#160;Materials table) which has the potential to be used in the clinic because it is portable, easy to set up (no subject preparation is required before a test), and does not require maintenance and sensor calibration. The photoelectric system consists of series of high-density floor-based photoelectric cells with light-emitting and light-receiving diodes that are placed parallel to each other to create a corridor, and are oriented perpendicular to the line of progression7. The system simply detects interruptions in light signal, for instance due to the presence of feet within the recording area. Temporal gait parameters and 1D spatial coordinates of consecutive steps are subsequently calculated to provide common gait parameters such as step length, single limb support and walking velocity8, whose validity against a criterion instrument has recently been demonstrated7,9. The measurement procedures are very straightforward; a single patient can be tested in less than 5 min&#160;and a comprehensive report can be generated in less than 1&#160;min.

This protocol is used to evaluate spatial and temporal gait variables of neurological/orthopedic patients and older persons by means of a recently-introduced floor-based photocell system.

Spatial and temporal characteristics of human walking are frequently evaluated to identify possible gait impairments, mainly in orthopedic and ...

Busulfan as a Myelosuppressive Agent for Generating Stable High-level Bone Marrow Chimerism in Mice

Bone marrow transplantation (BMT) is often used to replace the bone marrow (BM) compartment of recipient mice with BM cells expressing a distinct biomarker isolated from donor mice. This technique allows for identification of donor-derived hematopoietic cells within the recipient mice, and can be used to isolate and characterize donor cells using various biochemical techniques. BMT typically relies on myeloablative conditioning with total body irradiation to generate niche space within the BM compartment of recipient mice for donor cell engraftment. The protocol we describe here uses myelosuppressive conditioning with the chemotherapeutic agent busulfan. Unlike irradiation, which requires the use of specialized facilities, busulfan conditioning is performed using intraperitoneal injections of 20 mg/kg busulfan until a total dose of 60-100 mg/kg has been administered. Moreover, myeloablative irradiation can have toxic side effects and requires successful engraftment of donor cells for survival of recipient mice. In contrast, busulfan conditioning using these doses is generally well tolerated and mice survive without donor cell support. Donor BM cells are isolated from the femurs and tibiae of mice ubiquitously expressing green fluorescent protein (GFP), and injected into the lateral tail vein of conditioned recipient mice. BM chimerism is estimated by quantifying the number of GFP+ cells within the peripheral blood following BMT. Levels of chimerism&nbsp;>80% are typically observed in the peripheral blood 3-4 weeks post-transplant and remain established for at least 1 year. As with irradiation, conditioning with busulfan and BMT allows for the accumulation of donor BM-derived cells within the central nervous system (CNS), particularly in mouse models of neurodegeneration. This busulfan-mediated CNS accumulation may be more physiological than total body irradiation, as the busulfan treatment is less toxic and CNS inflammation appears to be less extensive. We hypothesize that these cells can be genetically engineered to deliver therapeutics to the CNS.

We describe a protocol whereby busulfan conditioning permits the bone marrow of a recipient mouse to be replaced with bone marrow cells from donor mice ubiquitously expressing green fluorescent protein, in the absence of irradiation. This technique is useful to study bone marrow cell accumulation in the central nervous system.

Bone marrow transplantation (BMT) is often used to replace the bone marrow (BM) compartment of recipient mice with BM cells expressing a distinct ...

A Multicenter MRI Protocol for the Evaluation and Quantification of Deep Vein Thrombosis

We evaluated a magnetic resonance venography (MRV) approach with gadofosveset to quantify total thrombus volume changes as the principal criterion for treatment efficacy&#160;in a multicenter randomized study comparing edoxaban monotherapy with a heparin/warfarin regimen for acute, symptomatic lower extremities deep vein thrombosis (DVT) treatment. We also used a direct thrombus imaging approach (DTHI, without the use of a contrast agent) to quantify fresh thrombus. We then sought to evaluate the reproducibility of the analysis methodology and applicability of using 3D magnetic resonance venography and direct thrombus imaging for the quantification of DVT in a multicenter trial setting. From 10 randomly selected subjects participating in the edoxaban Thrombus Reduction Imaging Study (eTRIS), total thrombus volume in the entire lower extremity deep venous system was quantified bilaterally. Subjects were imaged using 3D-T1W gradient echo sequences before (direct thrombus imaging, DTHI) and 5 min after injection of 0.03 mmol/kg of gadofosveset trisodium (magnetic resonance venography, MRV). The margins of the DVT on corresponding axial, curved multi-planar reformatted images were manually delineated by two observers to obtain volumetric measurements of the venous thrombi. MRV was used to compute total DVT volume, whereas DTHI was used to compute volume of fresh thrombus. Intra-class correlation (ICC) and Bland Altman analysis were performed to compare inter and intra-observer variability of the analysis. The ICC for inter and intra-observer variability was excellent (0.99 and 0.98, p &#60;0.001, respectively) with no bias on Bland-Altman analysis for MRV images. For DTHI images, the results were slightly lower (ICC = 0.88 and 0.95 respectively, p &#60;0.001), with bias for inter-observer results on Bland-Altman plots. This study showed feasibility of thrombus volume estimation in DVT using MRV with gadofosveset trisodium, with good intra- and inter-observer reproducibility in a multicenter setting.

The goal of this study is to use magnetic resonance venography with long-circulating gadolinium-based contrast agent and direct thrombus imaging for quantitative evaluation of DVT volume in a multicenter, clinical trial setting. Inter- and intra-observer variability assessments were conducted, and reproducibility of the protocol was determined.

We evaluated a magnetic resonance venography (MRV) approach with gadofosveset to quantify total thrombus volume changes as the principal criterion for ...

Using Saccadometry with Deep Brain Stimulation to Study Normal and Pathological Brain Function

The oculomotor system involves a large number of brain areas including parts of the basal ganglia, and various neurodegenerative diseases including Parkinson's and Huntington's can disrupt it. People with Parkinson's disease, for example, tend to have increased saccadic latencies. Consequently, the quantitative measurement of saccadic eye movements has received considerable attention as a potential biomarker for neurodegenerative conditions. A lot more can be learned about the brain in both health and disease by observing what happens to eye movements when the function of specific brain areas is perturbed. Deep brain stimulation is a surgical intervention used for the management of a range of neurological conditions including Parkinson's disease, in which stimulating electrodes are placed in specific brain areas including several sites in the basal ganglia. Eye movement measurements can then be made with the stimulator systems both off and on and the results compared. With suitable experimental design, this approach can be used to study the pathophysiology of the disease being treated, the mechanism by which DBS exerts it beneficial effects, and even aspects of normal neurophysiology.

This paper describes the use of quantitative measurement of eye movements in conjunction with stimulation of focal areas of the deep brain in order to study physiology, pathophysiology, and the mechanisms of deep brain stimulation.

The oculomotor system involves a large number of brain areas including parts of the basal ganglia, and various neurodegenerative diseases including ...

Assessment of Pulmonary Capillary Blood Volume, Membrane Diffusing Capacity, and Intrapulmonary Arteriovenous Anastomoses During Exercise

Exercise is a stress to the pulmonary vasculature. With incremental exercise, the pulmonary diffusing capacity (DLCO) must increase to meet the increased oxygen demand; otherwise, a diffusion limitation may occur. The increase in DLCO with exercise is due to increased capillary blood volume (Vc) and membrane diffusing capacity (Dm). Vc and Dm increase secondary to the recruitment and distension of pulmonary capillaries, increasing the surface area for gas exchange and decreasing pulmonary vascular resistance, thereby attenuating the increase in pulmonary arterial pressure. At the same time, the recruitment of intrapulmonary arteriovenous anastomoses (IPAVA) during exercise may contribute to gas exchange impairment and/or prevent large increases in pulmonary artery pressure.
We describe two techniques to evaluate pulmonary diffusion and circulation at rest and during exercise. The first technique uses multiple-fraction of inspired oxygen (FIO2) DLCO breath holds to determine Vc and Dm at rest and during exercise. Additionally, echocardiography with intravenous agitated saline contrast is used to assess IPAVAs recruitment.
Representative data showed that the DLCO, Vc, and Dm increased with exercise intensity. Echocardiographic data showed no IPAVA recruitment at rest, while contrast bubbles were seen in the left ventricle with exercise, suggesting exercise-induced IPAVA recruitment.
The evaluation of pulmonary capillary blood volume, membrane diffusing capacity, and IPAVA recruitment using echocardiographic methods is useful to characterize the ability of the lung vasculature to adapt to the stress of exercise in health as well as in diseased groups, such as those with pulmonary arterial hypertension and chronic obstructive pulmonary disease.

To assess the pulmonary diffusion and vasculature responses to exercise, we describe the multiple-inspired oxygen diffusion capacity technique to determine capillary blood volume and membrane diffusing capacity, as well as agitated saline contrast echocardiography to assess the recruitment of intrapulmonary arteriovenous anastomoses.

Exercise is a stress to the pulmonary vasculature. With incremental exercise, the pulmonary diffusing capacity (DLCO) must increase to meet the increased ...

Surgical Techniques to Optimize Ovarian Reserve during Laparoscopic Cystectomy for Ovarian Endometrioma

Surgical management of ovarian endometrioma in patients desiring fertility is complicated by the need to balance maximal resection of disease with efforts to spare normal ovarian cortex. Optimization of tubal anatomy is another frequent consideration. Fertility-sparing laparoscopic techniques at the time of cystectomy for ovarian endometrioma seek to limit iatrogenic surgical damage to the ovarian cortex and strategically assess and respond to genital tract patency. Surgical candidates frequently desire relief from endometriosis-associated pain while also seeking to optimize spontaneous or assisted conception rates. Operative benefits include potential for surgical and histopathologic diagnosis of endometriosis, evaluation of genital tract patency, and treatment of visualized lesions. Resection of ovarian endometrioma nonetheless poses significant risks, including surgical injury, blood loss, post-surgical decline in ovarian reserve and post-operative inflammation with adhesion formation, both of which may impair folliculogenesis.
We present the case of a 32-year-old woman with known endometriosis and continued pain refractory to medical management who opted for surgical management of her disease tailored toward optimizing her chances at future conception. Using this case as an example, we describe techniques and considerations for diagnostic laparoscopy, adhesiolysis, ovarian cystectomy, chromopertubation, and salpingectomy with a focus on maintaining a fertility-preserving approach.

This protocol presents techniques to laparoscopically excise ovarian endometrioma, to perform adhesiolysis with sparing electrosurgical application, and to employ intraoperative chromopertubation to assess for genital tract patency. This systematic approach will facilitate optimal endometriosis management, guide concomitant adnexal surgeries, and enhance post-surgical fertility outcomes.

Surgical management of ovarian endometrioma in patients desiring fertility is complicated by the need to balance maximal resection of disease with efforts ...