Name: Auteur in de schijnwerpers: vooruitgang in in vivo en ex vivo retinale beeldvorming voor verbeterde diagnose en behandeling van glaucoom
Uploaded: 2023-06-30T13:00:00
Description: Watch this Scientific Journal Video about Advancements in In Vivo and Ex Vivo Retinal Imaging for Improved Glaucoma Diagnosis and Treatment at JoVE.com

Deze studie wordt ondersteund door de Glaucoma Research Foundation Shaffer Grant, 4-CA Cavalier Collaborative Award, R01EY029121, R01EY035088 en Knights Templar Eye Foundation.

Alle dierproeven zijn goedgekeurd door de Institutional Animal Care and Use Committee van de Universiteit van Virginia en voldoen aan de richtlijn voor het gebruik van dieren van het National Institute of Health (NIH). Zie de Materiaaltabel voor details met betrekking tot alle materialen, reagentia en instrumenten die in dit protocol worden gebruikt.
1. In vivo vs-OCT-beeldvorming
<ol><li>Het vis-OCT-systeem<ol><li>Stel de ogen van de muizen voor me...

Muis Retina OCT Fibergram-uitlijning met confocale beelden

<ol>
	<li>Sernagor, E., Eglen, S. J., Wong, R. O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+retinal+ganglion+cell+structure+and+function.">Development of retinal ganglion cell structure and function.</a> Progress in Retinal and Eye Research. 20 (2), 139-174 (2001).</li><li>Sanes, J. R., Masland, R. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+types+of+retinal+ganglion+cells:+current+status+and+implications+for+neuronal+classification.">The types of retinal ganglion cells: current status and implications for neuronal classification.</a> Annual Review of Neuroscience. 38, 221-246 (2015).</li><li>Seabrook, T. A., Burbridge, T. J., Crair, M. C., Huberman, A. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Architecture,+function,+and+assembly+of+the+mouse+visual+system.">Architecture, function, and assembly of the mouse visual system.</a> Annual Review of Neuroscience. 40, 499-538 (2017).</li><li>Cang, J., Savier, E., Barchini, J., Liu, X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Visual+function,+organization,+and+development+of+the+mouse+superior+colliculus.">Visual function, organization, and development of the mouse superior colliculus.</a> Annual Review of Vision Science. 4, 239-262 (2018).</li><li>Quigley, H. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Understanding+glaucomatous+optic+neuropathy:+the+synergy+between+clinical+observation+and+investigation.">Understanding glaucomatous optic neuropathy: the synergy between clinical observation and investigation.</a> Annual Review of Vision Science. 2, 235-254 (2016).</li><li>Whitmore, A. V., Libby, R. T., John, S. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Glaucoma:+thinking+in+new+ways-a+role+for+autonomous+axonal+self-destruction+and+other+compartmentalised+processes.">Glaucoma: thinking in new ways-a role for autonomous axonal self-destruction and other compartmentalised processes.</a> Progress in Retinal and Eye Research. 24 (6), 639-662 (2005).</li><li>Syc-Mazurek, S. B., Libby, R. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Axon+injury+signaling+and+compartmentalized+injury+response+in+glaucoma.">Axon injury signaling and compartmentalized injury response in glaucoma.</a> Progress in Retinal and Eye Research. 73, 100769 (2019).</li><li>Puyang, Z., Chen, H., Liu, X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Subtype-dependent+morphological+and+functional+degeneration+of+retinal+ganglion+cells+in+mouse+models+of+experimental+glaucoma.">Subtype-dependent morphological and functional degeneration of retinal ganglion cells in mouse models of experimental glaucoma.</a> Journal of Nature and Science. 1 (5), (2015).</li><li>Tatham, A. J., Medeiros, F. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Detecting+structural+progression+in+glaucoma+with+optical+coherence+tomography.">Detecting structural progression in glaucoma with optical coherence tomography.</a> Ophthalmology. 124, S57-S65 (2017).</li><li>Shu, X., Beckmann, L., Zhang, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Visible-light+optical+coherence+tomography:+a+review.">Visible-light optical coherence tomography: a review.</a> Journal of Biomedical Optics. 22 (12), 1-14 (2017).</li><li>Miller, D. 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=Visible-light+optical+coherence+tomography+fibergraphy+for+quantitative+imaging+of+retinal+ganglion+cell+axon+bundles.">Visible-light optical coherence tomography fibergraphy for quantitative imaging of retinal ganglion cell axon bundles.</a> Translational Vision Science and Technology. 9 (11), (2020).</li><li>Beckmann, 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=In+vivo+imaging+of+the+inner+retinal+layer+structure+in+mice+after+eye-opening+using+visible-light+optical+coherence+tomography.">In vivo imaging of the inner retinal layer structure in mice after eye-opening using visible-light optical coherence tomography.</a> Experimental Eye Research. 211, 108756 (2021).</li><li>Grannonico, 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=Global+and+regional+damages+in+retinal+ganglion+cell+axon+bundles+monitored+non-invasively+by+visible-light+optical+coherence+tomography+fibergraphy.">Global and regional damages in retinal ganglion cell axon bundles monitored non-invasively by visible-light optical coherence tomography fibergraphy.</a> Journal of Neuroscience. 41 (49), 10179-10193 (2021).</li><li>Allen-Worthington, K. H., Brice, A. K., Marx, J. O., Hankenson, F. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intraperitoneal+Injection+of+Ethanol+for+the+Euthanasia+of+Laboratory+Mice+(Mus+musculus)+and+Rats+(Rattus+norvegicus).">Intraperitoneal Injection of Ethanol for the Euthanasia of Laboratory Mice (Mus musculus) and Rats (Rattus norvegicus).</a> J Am Assoc Lab Anim Sci. 54 (6), 769-778 (2015).</li><li>Boivin, G. P., Bottomley, M. A., Schiml, P. A., Goss, L., Grobe, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Physiologic,+Behavioral,+and+Histologic+Responses+to+Various+Euthanasia+Methods+in+C57BL/6NTac+Male+Mice.">Physiologic, Behavioral, and Histologic Responses to Various Euthanasia Methods in C57BL/6NTac Male Mice.</a> J Am Assoc Lab Anim Sci. 56 (1), 69-78 (2017).</li><li>Chen, H., 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=Progressive+degeneration+of+retinal+and+superior+collicular+functions+in+mice+with+sustained+ocular+hypertension.">Progressive degeneration of retinal and superior collicular functions in mice with sustained ocular hypertension.</a> Investigative Ophthalmology and Visual Science. 56 (3), 1971-1984 (2015).</li><li>Feng, L., Chen, H., Suyeoka, G., Liu, X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+laser-induced+mouse+model+of+chronic+ocular+hypertension+to+characterize+visual+defects.">A laser-induced mouse model of chronic ocular hypertension to characterize visual defects.</a> Journal of Visualized Experiments: JoVE. 78 (78), (2013).</li><li>Gao, J., 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=Differential+effects+of+experimental+glaucoma+on+intrinsically+photosensitive+retinal+ganglion+cells+in+mice.">Differential effects of experimental glaucoma on intrinsically photosensitive retinal ganglion cells in mice.</a> Journal of Comparative Neurology. 530 (9), 1494-1506 (2022).</li><li>Thomson, B. 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=Angiopoietin-1+knockout+mice+as+a+genetic+model+of+open-angle+glaucoma.">Angiopoietin-1 knockout mice as a genetic model of open-angle glaucoma.</a> Translational Vision Science and Technology. 9 (4), (2020).</li><li>Feng, 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=Sustained+ocular+hypertension+induces+dendritic+degeneration+of+mouse+retinal+ganglion+cells+that+depends+on+cell+type+and+location.">Sustained ocular hypertension induces dendritic degeneration of mouse retinal ganglion cells that depends on cell type and location.</a> Investigative Ophthalmology and Visual Science. 54 (2), 1106-1117 (2013).</li><li>Grannonico, 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=Longitudinal+analysis+of+retinal+ganglion+cell+damage+at+individual+axon+bundle+level+in+mice+using+visible-light+optical+coherence+tomography+fibergraphy.">Longitudinal analysis of retinal ganglion cell damage at individual axon bundle level in mice using visible-light optical coherence tomography fibergraphy.</a> Translational Vision Science and Technology. 12 (5), (2023).</li></ol>

Er zijn twee stappen in dit protocol die aandacht behoeven. Ten eerste is het noodzakelijk om ervoor te zorgen dat het dier onder diepe anesthesie is en dat hun ogen volledig verwijd zijn voordat ze OCT-beeldvorming zien. Als de muizen niet voldoende worden verdoofd, kan hun snelle ademhaling leiden tot onstabiele bewegingen van de en-face beelden, wat de kwaliteit van het fibergram nadelig kan beïnvloeden. Bovendien kan onvoldoende ontsluiting ook een negatieve invloed hebben op de beeldkwaliteit, aangezien de...

Retinale ganglioncellen (RGC's) spelen een cruciale rol bij de visuele informatieverwerking, ontvangen synaptische input via hun dendritische bomen in de binnenste plexiforme laag (IPL) en verzenden de informatie via hun axonen in de retinale zenuwvezellaag (RNFL) naar de hersenen 1,2,3,4. Bij zieke aandoeningen zoals glaucoom kan vroege RGC-degeneratie leiden tot subtiele veranderingen in de RNFL, de ganglioncellaag (GCL), de IPL en de oogzenuw bij zowel patiënten als knaagdiermodellen 5,6,7,8,9. Vroege detectie van deze morfologische veranderingen in RGC's is dus essentieel voor tijdige interventie om RGC en verlies van gezichtsvermogen te voorkomen.
We hebben onlangs een nieuwe klinische beeldvormingstechnologie ontwikkeld, genaamd optische coherentietomografie met zichtbaar licht (vis-OCT) om te voldoen aan de behoefte aan in vivo monitoring van RGC-schade. Vis-OCT verbeterde de axiale resolutie en bereikte 1,3 μm in het netvlies10,11, waardoor de visualisatie van individuele RGC-axonenbundels in de RNFL mogelijk werd. Vervolgens werd vis-OCT-vezelgrafie (vis-OCTF) vastgesteld om RGC-schade op het niveau van de enkele axonbundel bij muizen te volgen en te kwantificeren11,12,13. Ex vivo confocale beeldvorming van hetzelfde netvlies als de gouden standaard is echter vaak nodig om de in vivo bevindingen te valideren. Daarom zal deze studie aantonen hoe in vivo beelden verkregen door vis-OCTF kunnen worden uitgelijnd met ex vivo confocale beelden van hetzelfde netvlies van muizen. Het protocol heeft tot doel de in vivo bevindingen te valideren door middel van ex vivo confocale beeldvorming en een basis te leggen voor het onderzoeken van de moleculaire en cellulaire veranderingen die ten grondslag liggen aan RGC-schade bij zieke aandoeningen.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Equipment</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Halo 100</td>
			<td>Opticent Health, Evanston, IL</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Zeiss LSM800 microscope</td>
			<td>Carl Zeiss</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Drugs and antibodies</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>4% paraformaldehyde (PFA)</td>
			<td>Santz Cruz Biotechnology, SC-281692</td>
			<td></td>
			<td>1-2 drops</td>
		</tr>
		<tr>
			<td>Bovine serum albumin powder</td>
			<td>Fisher Scientific, BP9706-100</td>
			<td></td>
			<td>1:10</td>
		</tr>
		<tr>
			<td>Donkey anti Mouse Alexa Fluor 488 dye</td>
			<td>Thermo Fisher Scientific, Cat# A-21202</td>
			<td></td>
			<td>1:1,000</td>
		</tr>
		<tr>
			<td>Donkey anti rat Alexa Fluor 594 dye</td>
			<td>Thermo Fisher Scientific, Cat# A-21209</td>
			<td></td>
			<td>1:1,000</td>
		</tr>
		<tr>
			<td>Euthasol (a mixture of pentobarbital sodium (390 mg/mL) and phenytoin sodium (50 mg/mL))</td>
			<td>Covetrus, NDC 11695-4860-1</td>
			<td></td>
			<td>15.6 mg/mL</td>
		</tr>
		<tr>
			<td>Ketamine</td>
			<td>Covetrus, NADA043304</td>
			<td></td>
			<td>114 mg/kg</td>
		</tr>
		<tr>
			<td>Mouse anti-Tuj1</td>
			<td>A gift from Anthony J. Spano, University of Virginia</td>
			<td></td>
			<td>1:200</td>
		</tr>
		<tr>
			<td>Normal donkey serum(NDS)</td>
			<td>Millipore Sigma, S30-100 mL</td>
			<td></td>
			<td>1:100</td>
		</tr>
		<tr>
			<td>Phosphate-buffered saline (PBS, 10x), pH 7.4 
			(Contains 1370 mM NaCl, 27 mM KCl, 80 mM Na2HPO4, and 20 mM KH2PO4)</td>
			<td>Thermo Fisher Scientific, Cat# J62036.K3</td>
			<td></td>
			<td>1:10</td>
		</tr>
		<tr>
			<td>Rat anti-ICAM-2</td>
			<td>BD Pharmingen, Cat#553325</td>
			<td></td>
			<td>1:500</td>
		</tr>
		<tr>
			<td>Tropicamide drops&#160;</td>
			<td>Covetrus, NDC17478-102-12</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Triton X-100 
			(Reagent Grade)</td>
			<td>VWR, CAS: 9002-93-1</td>
			<td></td>
			<td>1:20</td>
		</tr>
		<tr>
			<td>Vectashield mounting medium</td>
			<td>Vector Laboratories Inc. H2000-10</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Xylazine</td>
			<td>Covetrus, NDC59399-110-20</td>
			<td></td>
			<td>17 mg/kg</td>
		</tr>
	</tbody>
</table>

alignment of visible-light optical coherence tomography fibergrams with confocal images of the same mouse retina

In de afgelopen jaren is in vivo retinale beeldvorming, die niet-invasieve, real-time en longitudinale informatie over biologische systemen en processen biedt, steeds vaker toegepast om een objectieve beoordeling van neurale schade bij oogziekten te verkrijgen. Ex vivo confocale beeldvorming van hetzelfde netvlies is vaak nodig om de in vivo bevindingen te valideren, vooral in dieronderzoek. In deze studie demonstreerden we een methode om een ex vivo confocaal beeld van het netvlies van de muis uit te lijnen met de in vivo beelden. Een nieuwe klinische beeldvormingstechnologie, optische coherentietomografievezelgrafie met zichtbaar licht (vis-OCTF) genaamd, werd toegepast om in vivo beelden van het netvlies van de muis te verkrijgen. Vervolgens voerden we de confocale beeldvorming uit van hetzelfde netvlies als de "gouden standaard" om de in vivo vis-OCTF-beelden te valideren. Deze studie maakt niet alleen verder onderzoek van de moleculaire en cellulaire mechanismen mogelijk, maar legt ook de basis voor een gevoelige en objectieve evaluatie van neurale schade in vivo.

Retinal ganglion cells (RGCs) play a critical role in visual information processing, receiving synaptic inputs through their dendritic trees in the inner plexiform layer (IPL) and transmitting the information via their axons in the retinal nerve fiber layer (RNFL) to the brain1,2,3,4. In diseased conditions such as glaucoma, early RGC degeneration may result in subtle changes in the RNFL, the ganglion cell layer (GCL), the IPL, and the optic nerve in both patients and rodent models5,6,7,8,9. Early detection of these morphological changes in RGCs is thus essential for timely intervention to prevent RGC and vision loss.
We have recently developed a new clinical-ready imaging technology called visible-light optical coherence tomography (vis-OCT) to satisfy the need for in vivo monitoring of RGC damage. Vis-OCT improved the axial resolution, reaching 1.3 &#181;m in the retina10, 11, allowing for the visualization of individual RGC axon bundles in the RNFL. Subsequently, vis-OCT fibergraphy (vis-OCTF) was established to track and quantify RGC damage at the single axon bundle level in mice11,12,13. However, ex vivo confocal imaging of the same retina as the gold standard is often necessary to validate the in vivo findings. Therefore, this study will demonstrate how to align in vivo images acquired by vis-OCTF with ex vivo confocal images of the same mouse retina. The protocol aims to validate the in vivo findings by ex vivo confocal imaging and establish a foundation for examining the molecular and cellular changes underlying RGC damage in diseased conditions.

Auteur in de schijnwerpers: vooruitgang in in vivo en ex vivo retinale beeldvorming voor verbeterde diagnose en behandeling van glaucoom 

Uitlijning van optische coherentietomografievezelgrammen in zichtbaar licht met confocale beelden van hetzelfde netvlies van de muis

We present a protocol for aligning in vivo VIS-OCT images with ex vivo immunostained retinal nerve fibers to validate our novel imaging technology. VIS-OCT enables visualization of retinal nerve fibers in vivo, and this process confirms the accuracy of our findings. Our protocol combines in vivo and ex vivo imaging to provide a real time visualization of retina structure and confirm findings.The process is applicable to mouse models of eye diseases, provided the anterior eye portion allows for optical imaging. This includes diabetic retinopathy and retinal ischemia models. These studies lay the foundation for establishing an objective evaluation of neuro damage in humans, which can significantly improve glaucoma diagnosis and treatment in the future.

Het composiet vis-OCT-fibergram wordt vergeleken met het overeenkomstige confocale beeld van plat gemonteerd netvlies dat immuungekleurd is met Tuj-1 voor RGC-axonen (Figuur 1D, bovenste paneel). Axonbundels afgebeeld door vis-OCTF kunnen worden gematcht met de Tu-j1-gelabelde axonbundels op de confocale afbeelding. Bloedvaten vertonen meestal te onderscheiden vertakkingsstructuren in vergelijking met omringende axonbundels in vezelgrambeelden, die kunnen worden vergeleken met de ICAM-2-gela...

Watch this Scientific Journal Video about Advancements in In Vivo and Ex Vivo Retinal Imaging for Improved Glaucoma Diagnosis and Treatment at JoVE.com

Het huidige protocol schetst de stappen voor het in vivo uitlijnen van optische coherentietomografie-vezelgrafiebeelden (vis-OCTF) in vivo met ex vivo confocale beelden van hetzelfde netvlies van muizen met het oog op het verifiëren van de waargenomen morfologie van de axonbundel van retinale ganglioncellen in de in vivo beelden.

In recent years, in vivo retinal imaging, which provides non-invasive, real-time, and longitudinal information about biological systems and processes, has ...

We presenteren een protocol voor het uitlijnen van in vivo VIS-OCT-beelden met ex vivo immunogekleurde retinale zenuwvezels om onze nieuwe beeldvormingstechnologie te valideren. VIS-OCT maakt visualisatie van retinale zenuwvezels in vivo mogelijk, en dit proces bevestigt de nauwkeurigheid van onze bevindingen. Ons protocol combineert in vivo en ex vivo beeldvorming om een real-time visualisatie van de netvliesstructuur te bieden en bevindingen te bevestigen.Het proces is toepasbaar op muismodellen van oogziekten, op voorwaarde dat het voorste ooggedeelte optische beeldvorming mogelijk maakt. Dit omvat diabetische retinopathie en modellen voor retinale ischemie. Deze studies leggen de basis voor het opzetten van een objectieve evaluatie van neuroschade bij mensen, die de diagnose en behandeling van glaucoom in de toekomst aanzienlijk kan verbeteren.

alignment-visible-light-optical-coherence-tomography-fibergrams-with

Research

JoVE Journal

Neuroscience

Alignment of Visible-Light Optical Coherence Tomography Fibergrams with Confocal Images of the Same Mouse Retina

In recent years, in vivo retinal imaging, which provides non-invasive, real-time, and longitudinal information about biological systems and processes, has been increasingly applied to obtain an objective assessment of neural damage in eye diseases. Ex vivo confocal imaging of the same retina is often necessary to validate the in vivo findings especially in animal research. In this study, we demonstrated a method for aligning an ex vivo confocal image of the mouse retina with its in vivo images. A new clinical-ready imaging technology called visible light optical coherence tomography fibergraphy (vis-OCTF) was applied to acquire in vivo images of the mouse retina. We then performed the confocal imaging of the same retina as the &#34;gold standard&#34; to validate the in vivo vis-OCTF images. This study not only enables further investigation of the molecular and cellular mechanisms but also establishes a foundation for a sensitive and objective evaluation of neural damage in vivo.

The present protocol outlines the steps for aligning in vivo visible-light optical coherence tomography fibergraphy (vis-OCTF) images with ex vivo confocal images of the same mouse retina for the purpose of verifying the observed retinal ganglion cell axon bundle morphology in the in vivo images.

In Vivo Visible Light Optical Coherence Tomography (OCT) Mouse Retinal Imaging

Start by positioning the anesthetized mouse on the animal holder and securing it with two Velcro straps. Turn on the computer and open the software to activate the laser. Adjust the animal holder to center the laser in the mouse's eye.Visualize the posterior part through an on-face preview, the field of view of the superficial vascular plexus, a B scan, and the retina cross-section within the field of view. Acquire a visible light optical coherence tomography, or vis-OCT volume after making minor adjustments to the optical focus. Align the optical nerve head in each of the four corners of the field of view to cover different retinal areas.Use an intensity-based threshold method to detect the retina surface, and generate vis-OCT fiber grams from the volume. Crop the retinal nerve fiber layer, or RNFL, by selecting the first 16 micrometers depth. Next, calculate the mean intensity projection along the axial direction to generate the fiber gram image composed of retinal ganglion cell axon bundles and surrounding vasculature.Align the blood vessels using a graphics editor to montage the four images post-processing. The composite vis-OCT fiber gram is compared with the corresponding confocal image of flat-mounted retina immunostained with TUJ1 for RGC axons. Blood vessels exhibit distinguishable branching structures which can be matched with the ICAM II labeled blood vessels on the confocal image.Side-by-side comparison between ex vivo confocal microscopy and in vivo vis-OCT revealed identical RGC exon bundle networks and surrounding retinal vasculature.

In vivo zichtbaar licht optische coherentietomografie (OCT) Retinale beeldvorming bij muizen

Ex Vivo Confocal Imaging of Mouse Retina

Enucleate the eyes of a euthanized mouse, marking the temporal side for orientation purposes. Remove the anterior chamber. Then remove the lens and vitreous and place eye cups in paraformaldehyde for 30 minutes.Wash eye cups with PBS for 30 minutes. Replacing the solution three times. Then, wash with 0.5%Triton X-100 for 30 minutes.Incubate eye cups in the blocking buffer for two hours at room temperature. After immunostaining, isolate the retinas from the eye cups using a microscope. Divide the retinas into four leaves and flat mount them with the retinal ganglion cell layer facing up.Ensure the mark on the temporal side remains attached for orientation. Cover the retinas with mounting medium. Place cover slips.And seal the slides using nail polish. Turn on the confocal microscope and under Locate mode, find the area of interest using the eye piece. Switch to Acquisition mode and set up tiles to cover the entire retina, along with Z-Stack slices for all layers of information.Image at least 25 tiles across the whole retina to achieve a total volume. Project the Z-Stack slices to generate two-dimensional on-face confocal microscopy images. The composite vis-OCT fibergram is compared with the corresponding confocal image of flat mounted retina immunostained with TuJ1 for RGC axons.Blood vessels exhibit distinguishable branching structures which can be matched with the ICAM-2 labeled blood vessels on the confocal image. Side-by-side comparison between ex vivo confocal microscopy and in vivo vis-OCT revealed identical RGC axon bundle networks and surrounding retinal vasculature.

Ex vivo confocale beeldvorming van het netvlies van muizen

Alignment of In Vivo and Ex Vivo Mouse Retinal Images

Start by creating a composite image using the four obtained images from each mouse. Utilize a graphics editor to align all the blood vessels, employ the optic nerve head and blood vessel patterns as landmarks for aligning the composite fiber gram overlap the composite images and the confocal images of the same retina stained with ICAM2, to achieve in vivo and ex vivo alignment. The composite vis-oct fiber gram is compared with the corresponding confocal image of flat mounted retina.Immuno stain with TUJ1 for RGC axons. Blood vessels exhibit distinguishable branching structures which can be matched with the ICAM2 labeled blood vessels on the confocal image. Side-by-side comparison between ex vivo confocal microscopy and in vivo vis-oct revealed identical RGC Axon bundle networks and surrounding retinal vasculature.