Name: Inducement and Evaluation of a Murine Model of Experimental Myopia (Video) | JoVE Journal
Uploaded: 2019-01-22T14:30:00.000+00:00
Duration: 7 min 20 s
Description: Learn to induce and evaluate lens-induced myopia in mice using head-mounted eyeglasses with standardized protocols. This method enables precise, reproducible measurements of refraction and axial length for ophthalmology research.

ai_agent_IP

ai_agent

maintenance

instantTrialDurationMinutes

isBiopharma

enableNewMyJoveSectionDesign

educationFeatures

seoMetaApi

ai_copilot_institution_blacklist

ai_chat_institution_blacklist

freeAccessWindow

ssoRoleCapture

scheduledMaintenanceBanner

joveLabsFeatures

disable_autoplay_for_bots

extended_trial_duration

5 minutes

We thank M.T. Pardue for advice on the SD&#173;OCT, F. Schaeffel for advice on measurements of refraction and corneal curvature, Mr. Sanshouo for recreating the three-dimensional frame data, M. Miyauchi; K. Tsubota; Y. Tanaka; S. Kondo; C. Shoda; M. Ibuki; Y. Miwa; Y. Hagiwara; A. Ishida; Y. Tomita; Y. Katada; E. Yotsukura; K. Takahashi; and Y. Wang for critical discussions. This work was supported by Grants&#173; in&#173;Aid for Scientific Research (KAKENHI, number 15K10881) from the Ministry of Education, Culture, Sports, Science and Technology (MEXT) to TK. This work is also supported by the grant for myopia research from Tsubota Laboratory, Inc. (Tokyo Japan).

All procedures were approved by the Ethics Committee on Animal Research of the Keio University School of Medicine adhered to the ARVO Statement for the Use of Animals in Ophthalmic and Vision Research, the Institutional Guidelines on Animal Experimentation at Keio University, and the Animal Research: Reporting of In Vivo Experiments (ARRIVE) guidelines for the use of animals in research.
1. Assembling the Eyeglasses for Mice
<ol>
	<li>Prepare parts needed for assembling the eyeglasses (Figure 1a). For each mouse, prepare all followings: one head-mounted nylon stick, one higher and one lower titanium frame, two lenses with proper powers according to the purpose of the experiment, one M1.4 size screw with the length of 10 mm, one nut for M1.4 size screw, one plain washer for M1.4 size screw with the thickness of 0.3 mm, and two artificial fingernail tips (Table of Materials). 
	NOTE: Two kinds of frames exist with different heights. For one mouse, one higher frame and one lower frame are used as a set. Higher frames should be put above the lower ones in order to make the vision fields symmetrical. Frames and lenses are specially designed and manufactured by authors&#8217; research group. These are available by contacting the corresponding authors of this article. Other parts can be found in retail tool shops.</li>
	<li>Assemble the frame for the right and left eye separately.
	<ol>
		<li>Arrange the fingernail tip to face the outside direction to achieve the best protective effect. Adjust the angle between the fingernail tip and the frame to be about 130&#176; to avoid masking the mouse vision field (Figure 1b). Adhere the artificial fingernail tips to the frame using cyanoacrylate adhesive. 
		NOTE: Fingernail tips can help to protect the lens from being scratched by the mouse. The direction of the fingernail tips must be opposite because the higher frame and the lower frame are used for the right eye and the left eye, respectively.</li>
		<li>Wait for at least 12 h to let the adhesive dry completely, then use a nail clipper to adjust the shape of the fingernail tips to be about 1 cm &#215; 1 cm by cutting and trimming.</li>
		<li>Adhere the lens to the frame using cyanoacrylate adhesive. Put the lens onto the frame by hand and hold the frame horizontally. Inject the cyanoacrylate adhesive from the edge of the lens and let the adhesive spread by surface tension. 
		NOTE: The adhesive will erode the lens and influence its transparency, so make sure the adhesive only touches the peripheral part of the lens. Use 0 diopter (D) plano lens as control and minus lens to induce myopia. The effect of different powers of minus lenses (&#8211;10 D to &#8211;50 D) has been described elsewhere4. To maximize the myopia inducement, &#8211;30 D lens is recommended for inducing myopia. FDM can also be induced with the same device simply by changing the lens into the cap of 1.5 mL microtube as the diffuser.</li>
	</ol>
	</li>
	<li>Tighten the screw into the nylon stick together with the washer from the flat side of the stick. Prepare the eye glasses and sticks before the experiment respectively and stock for further use (Figure 1c). 
	NOTE: The protocol can be paused here.</li>
</ol>
2. Measurements of the Refraction and AL Baseline.
<ol>
	<li>Apply one drop of mydriatic agent containing 5 mg/mL tropicamide and 5 mg/mL phenylephrine hydrochloride on each side of the eyeball to dilate the pupil. Wait for at least 5 min before general anesthesia. 
	NOTE: Dilate the pupil under general anesthesia will cause reversible cataract which influences the measurement afterwards. Always dilate the pupil before general anesthesia and wait for at least 5 min. One drop (approximately 0.05 mL) of the mydriatic agent is enough for dilating the pupil of the mouse eye, while more agent will do no harm to the following steps.</li>
	<li>Put the mouse under general anesthesia. Grasp the back skin of the mouse softly to keep the mouse from bumping its eye until it is completely anaesthetized. Judge the depth of general anesthesia to be enough if the mouse does not move around when it is put on the table freely. 
	NOTE: A combination of midazolam (40 &#956;g/100 &#956;L), medetomidine (7.5 &#956;g/100 &#956;L) and butorphanol tartrate (50 &#956;g/100 &#956;L) is used here for general anesthesia for mice with a volume of 0.01 mL/g intraperitoneal injection. Generally, less than 5 min are needed for mice to fall asleep. Long time of general anesthesia causes low body temperature and slow heartbeat. To avoid the potential influence of general anesthesia to the measurement, finishing all the measurements within 10 min after the injection of anesthetic is recommended.&#160;The butorphanol provided in the anesthetic cocktail provide approximately 4 hours of analgesia. Proper recipe for general anesthesia may different by institutions.</li>
	<li>Measure the refraction of the mouse eye using an infrared photorefractor4,9,14. Adjust the direction of one of the mouse eyes to keep the first Purkinje image in the center of the pupil and measure the refraction along the optical axis. After the measurement, measure the opposite eye with the same procedures (Figure 2a). 
	NOTE: The value measured for the refraction is strongly influenced by the position of the mouse eye along the optic axis. Ensure the first Purkinje image is aligned within &#177;3 degrees from the center of the pupil. The workbench of the spectral domain optical coherence tomography (SD-OCT) system may be used for fine tuning of the direction of pupil in refraction measurements4.</li>
	<li>Measure the AL of the mouse eye using a SD-OCT system4,15,16. Define the AL as the distance from the corneal vertex to the brightest boundary near the optical nerve (Figure 2b). 
	NOTE: Similar with the measurement of the refraction, the AL is strongly influenced by the direction of the mouse eye. The corneal vertex can be confirmed by the point-like reflection on the surface of the cornea. The boundary of the retina side will be very hazy at the point of optical nerve. Adjust the direction a little to let the boundary be clear enough for measuring but not too far from the optical nerve.</li>
</ol>
3. Fixation of the Frame onto the Mouse Cranium.
<ol>
	<li>Apply one drop of 0.1% purified sodium hyaluronate eye drop to prevent dryness on each eye. 
	NOTE: Eye drop on the eye surface will influence the values of refraction and axial length measurements. Do not use the eye drop after the anesthesia until all the measurements are done.</li>
	<li>Put the chin of the anesthetized mouse onto a slope made of clay or anything can be used as a pillow to make the upfront plane of the cranium be horizontal.</li>
	<li>Sterilize the hair and scalp between ears and eyes using cotton swab with 70% ethanol.</li>
	<li>Cut the skin between ears and eyes to expose the skull for about 0.8 cm2 using surgical scissors and tweezers. Use dental etching liquid and cotton swab to remove the periosteum. Sterilize the surgical scissors and tweezers with 70% ethanol before the surgery of each mouse. 
	NOTE: Clipping the hair and wearing sterile gloves may be required.&#160; Check the provisions of relevant animal care committee before this procedure.&#160;In most cases, the dental etching liquid can be found as one of the attachments in the self-cure dental adhesive system. If the dental etching liquid is not available, use 70% ethanol instead.</li>
	<li>Assemble a set of frames without lens to help fix the stick onto the right position. Put the frames onto the mouse head. Carefully adjust the position of the frames to make sure both eyes are in the middle of the empty frame.</li>
	<li>Use a self-cure dental adhesive system to attach the stick onto the mouse head. Be careful not to let the liquid of the adhere system flow into the mouse eye. 
	NOTE: The method for using the self-cure dental adhesive system is different between products. Refer to the instruction carefully. 
	CAUTION: Some of the reagents in the dental adhesive system may be toxic.</li>
	<li>Wait for about 5 min and take off the frame and the nut carefully without changing the position of the stick (Figure 3a).</li>
	<li>Inject 0.75 mg/kg atipamezole hydrochloride intraperitoneally to help the mouse to recovery from the anesthesia more quickly. Put the mouse into an individual cage until fully recovered. Do not leave the mouse unattended until it has regained sufficient consciousness to maintain sternal recumbency. The protocol can be paused here.</li>
</ol>
4. Initiation of the Myopia Induction and the Maintenance Afterwards
<ol>
	<li>Wait for at least 24 h after the surgery to let the mouse recover from anesthesia completely. Grasp the stick and put on the frames with lenses. The inducement begins at this time point (Figure 3b). 
	NOTE: To minimize the discomfort during the recovery from anesthesia and give enough time for the dental adhesive system to coagulate, it is highly recommended to put on the frame after the mice fully recovered from anesthesia. The resin cement of the adhesive system will fully cover the cut of the scalp. Therefore, no specific post-surgical treatment is needed for preventing infection and ameliorating post-surgical pain. Right after the first time of putting on the frame, mice will be over conscious to the existence of the lens and scratch it a lot. The gross behavior will be back to normal after a few hours.&#160;The mice with lenses can be kept with the same density to the normal mice.</li>
	<li>Remove the frame and clean the lenses and fingernail tips with cotton swabs at least twice a week to maintain the transparency of the lens. 
	NOTE: It is not necessary to put the mouse under anesthesia for removing and putting on the frame.&#160;Provide a support for the mice to sit on, rather than having them hang while working with them could reduce distress.
	<ol>
		<li>If an interim measurement is necessary, put the mouse under anesthesia and measure the mouse as previously described. The inducement can be continued after the mouse recovering from the anesthesia.</li>
	</ol>
	</li>
	<li>Clean the cage at least twice a week. 
	NOTE: This help to maintain lens clarity. Putting a net between the mouse and the cage bottom to filtrate the food scraps may also be helpful.</li>
	<li>Monitor the body weight and gross behavior. Compare them with the same age untouched mice during the whole experimental process. 
	NOTE: Except for some scratching behaviors, no significant change including the body weight is found between experiment mice with untreated mice.</li>
</ol>

<ol><li>Dolgin, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((The+myopia+boom%5BTitle%5D)+AND+%22Nature%22%5BJournal%5D)">The myopia boom.</a> Nature. 519 (7543), 276-278 (2015).</li>
<li>Ohno-Matsui, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Pathologic+Myopia%5BTitle%5D)+AND+%22Asia-Pacific+Journal+of+Ophthalmology+%28Philadelphia%2C+Pa%29%22%5BJournal%5D)">Pathologic Myopia.</a> Asia-Pacific Journal of Ophthalmology (Philadelphia, Pa). 5 (6), 415-423 (2016).</li>
<li>Morgan, I. G., Ashby, R. S., Nickla, D. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Form+deprivation+and+lens-induced+myopia%3A+are+they+different%5BTitle%5D)+AND+%22Ophthalmic+%26+Physiological+Optics%22%5BJournal%5D)">Form deprivation and lens-induced myopia: are they different.</a> Ophthalmic & Physiological Optics. 33 (3), 355-361 (2013).</li>
<li>Jiang, X., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((A+highly+efficient+murine+model+of+experimental+myopia%5BTitle%5D)+AND+%22Scientific+Reports%22%5BJournal%5D)">A highly efficient murine model of experimental myopia.</a> Scientific Reports. 8 (1), 2026(2018).</li>
<li>Torii, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Violet+Light+Exposure+Can+Be+a+Preventive+Strategy+Against+Myopia+Progression%5BTitle%5D)+AND+%22EBioMedicine%22%5BJournal%5D)">Violet Light Exposure Can Be a Preventive Strategy Against Myopia Progression.</a> EBioMedicine. 15, 210-219 (2017).</li>
<li>Smith, E. L. 3rd, et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Effects+of+Long-Wavelength+Lighting+on+Refractive+Development+in+Infant+Rhesus+Monkeys%5BTitle%5D)+AND+%22Investigative+Ophthalmology+%26+Visual+Science%22%5BJournal%5D)">Effects of Long-Wavelength Lighting on Refractive Development in Infant Rhesus Monkeys.</a> Investigative Ophthalmology & Visual Science. 56 (11), 6490-6500 (2015).</li>
<li>Gawne, T. J., Siegwart, J. T., Ward, A. H., Norton, T. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((The+wavelength+composition+and+temporal+modulation+of+ambient+lighting+strongly+affect+refractive+development+in+young+tree+shrews%5BTitle%5D)+AND+%22Experimental+Eye+Research%22%5BJournal%5D)">The wavelength composition and temporal modulation of ambient lighting strongly affect refractive development in young tree shrews.</a> Experimental Eye Research. 155, 75-84 (2017).</li>
<li>Wu, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Early+quantitative+profiling+of+differential+retinal+protein+expression+in+lens-induced+myopia+in+guinea+pig+using+fluorescence+difference+two-dimensional+gel+electrophoresis%5BTitle%5D)+AND+%22Molecular+Medicine+Reports%22%5BJournal%5D)">Early quantitative profiling of differential retinal protein expression in lens-induced myopia in guinea pig using fluorescence difference two-dimensional gel electrophoresis.</a> Molecular Medicine Reports. , (2018).</li>
<li>Schaeffel, F., Burkhardt, E., Howland, H. C., Williams, R. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Measurement+of+refractive+state+and+deprivation+myopia+in+two+strains+of+mice%5BTitle%5D)+AND+%22Optometry+and+Vision+Science%22%5BJournal%5D)">Measurement of refractive state and deprivation myopia in two strains of mice.</a> Optometry and Vision Science. 81 (2), 99-110 (2004).</li>
<li>Tkatchenko, T. V., Shen, Y., Tkatchenko, A. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Mouse+experimental+myopia+has+features+of+primate+myopia%5BTitle%5D)+AND+%22Investigative+Ophthalmology+%26+Visual+Science%22%5BJournal%5D)">Mouse experimental myopia has features of primate myopia.</a> Investigative Ophthalmology & Visual Science. 51 (3), 1297-1303 (2010).</li>
<li>Faulkner, A. E., Kim, M. K., Iuvone, P. M., Pardue, M. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Head-mounted+goggles+for+murine+form+deprivation+myopia%5BTitle%5D)+AND+%22Journal+of+Neuroscience+Methods%22%5BJournal%5D)">Head-mounted goggles for murine form deprivation myopia.</a> Journal of Neuroscience Methods. 161 (1), 96-100 (2007).</li>
<li>Gu, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((A+Head-Mounted+Spectacle+Frame+for+the+Study+of+Mouse+Lens-Induced+Myopia%5BTitle%5D)+AND+%22Journal+of+Ophthalmology%22%5BJournal%5D)">A Head-Mounted Spectacle Frame for the Study of Mouse Lens-Induced Myopia.</a> Journal of Ophthalmology. 2016, 8497278(2016).</li>
<li>Siegwart, J. T. Jr, Norton, T. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Goggles+for+controlling+the+visual+environment+of+small+animals%5BTitle%5D)+AND+%22Laboratory+Animal+Science%22%5BJournal%5D)">Goggles for controlling the visual environment of small animals.</a> Laboratory Animal Science. 44 (3), 292-294 (1994).</li>
<li>Tkatchenko, T. V., Tkatchenko, A. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Ketamine-xylazine+anesthesia+causes+hyperopic+refractive+shift+in+mice%5BTitle%5D)+AND+%22Journal+of+Neuroscience+Methods%22%5BJournal%5D)">Ketamine-xylazine anesthesia causes hyperopic refractive shift in mice.</a> Journal of Neuroscience Methods. 193 (1), 67-71 (2010).</li>
<li>Chou, T. H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Postnatal+elongation+of+eye+size+in+DBA%2F2J+mice+compared+with+C57BL%2F6J+mice%3A+in+vivo+analysis+with+whole-eye+OCT%5BTitle%5D)+AND+%22Investigative+Ophthalmology+%26+Visual+Science%22%5BJournal%5D)">Postnatal elongation of eye size in DBA/2J mice compared with C57BL/6J mice: in vivo analysis with whole-eye OCT.</a> Investigative Ophthalmology & Visual Science. 52 (6), 3604-3612 (2011).</li>
<li>Park, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Assessment+of+axial+length+measurements+in+mouse+eyes%5BTitle%5D)+AND+%22Optometry+and+Vision+Science%22%5BJournal%5D)">Assessment of axial length measurements in mouse eyes.</a> Optometry and Vision Science. 89 (3), 296-303 (2012).</li>
</ol>

The design of the mouse eyeglass has been applied for a patent (Application no. 2017&#173;41349).

To make sure the eyeglasses to be fixed stably on the mouse head, several steps in this protocol need to be paid great attention. The periosteum must be removed completely before using the dental adhesive system. The blood on the skull also need to be cleaned up with care. While a little fine tuning is acceptable right after the application of the adhesive, do not move the stick frequently before the adhesive system dry up. Follow the instruction of the adhesive system carefully, especially the ratio of each component of...

The prevalence of myopia has increased dramatically recently, while the mechanism of its onset and progression are still largely unknow1. The most characteristic phenotype of myopia is the elongation of axial length (AL), which increases risk for retinal complications or even blindness2. To better understand the pathogenesis of myopia and develop effective treatments, robust myopic animal models and stable phenotype evaluation are necessary.
Briefly, two methods exist for inducing myopic states in animals: form-deprivation myopia (FDM) and lens-induced myopia (LIM)3. The former places diffusers in front of the eye or sutures the eyelid to obscure the image, which influences the normal development of the eyeball, resulting in a myopia phenotype. The latter places minus lenses in front of the eye to move the focal point behind the retina. The retina detects the shift of the focus and elongates the eyeball to realign the retina and focal point. For FDM, after the eyelid is closed or the diffuser has been fixed in front of the eye, almost no further maintenance is needed. For LIM, the lens needs to be taken off for cleaning in order to keep it transparent. Thus, FDM is relatively easy to be induced technically. However, the mechanisms of FDM and LIM are different, and which method mimics the myopia in human better is still under debate3. One of the strengths of LIM is the stronger phenotype compared with FDM, at least in the case of mice4.
Animals that have been used for inducing myopia include chicks5, monkeys6, tree shrews7, guinea pigs8, and mice4. Considering the possibility of genetic manipulation, abundant available antibodies, and low cost for breeding, mice could have been the first choice as the animal model of myopia. However, compared with other larger animals, fixing lenses or diffusers in front of the mouse eye is relatively difficult especially for young mice such as right after weaning. For the experiments that need topical drug administration or multiple interim eye measurements, it is also necessary for the frame to be removable. Another challenge is the small morphological change of mouse eyeball, which needs sophisticated technics and devices to evaluate. To date, different inducing and measuring protocols used in different research teams make it hard to compare and repeat the results across laboratories. A standard protocol with details is needed.
Previous works described multiple methods to fix lenses or diffusers in front of the mouse eye, such as gluing9, stitching10 and head-mounted goggle frame11,12. We combined the exist head-mounted goggle technics11,12,13 with our newly designed frame to develop an ameliorated protocol for inducing robust and efficient experimental myopia in mice. The protocol can be applied to young mice soon after weaning at postnatal day 21 (p21). We also optimized the processes for stable and precise evaluation of phenotypes including the refraction and AL. We hope this standardized protocol can help to make myopic mice a more easily accessible model for myopia research.

<table><tbody><tr><td>screw</td><td>NBK</td><td>SNZS-M1.4-10</td><td></td></tr><tr><td>washer</td><td>MonotaRO</td><td>42166397</td><td></td></tr><tr><td>nut</td><td>MonotaRO</td><td>42214243</td><td></td></tr><tr><td>stick</td><td>DMM Make</td><td>none</td><td>designed by authers and output by the 3D printer rented from DMM Make.</td></tr><tr><td>frame</td><td>DMM Make</td><td>none</td><td>designed by authers and output by the 3D printer rented from DMM Make.</td></tr><tr><td>lenses</td><td>RAINBOW CONTACT LENS</td><td>none</td><td>customized for mice use by the company</td></tr><tr><td>cyanoacrylate glue</td><td>OK MODEL</td><td>MP 20g</td><td></td></tr><tr><td>dental adhesive resin cement</td><td>SUN MEDICAL</td><td>super bond</td><td>contains the etching liquid used for removing the periosteum of the mouse skull</td></tr><tr><td>infrared photorefractor</td><td>Steinbeis Transfer Center</td><td>none</td><td>designed and offered by Dr. Frank Schaeffel from university of T&amp;uuml;bingen</td></tr><tr><td>Spectral domain OCT</td><td>Leica</td><td>R4310</td><td></td></tr><tr><td>Tropicamide, Penylephrine Hydrochloride solution</td><td>Santen</td><td>Mydrin-P</td><td></td></tr><tr><td>midazolam</td><td>Sandoz K.K.</td><td>SANDOZ</td><td>components for the anesthetic</td></tr><tr><td>medetomidine&amp;nbsp;</td><td>Orion Corporation</td><td>Domitor</td><td>components for the anesthetic</td></tr><tr><td>butorphanol tartrate&amp;nbsp;</td><td>Meiji Seika Pharma</td><td>Vetorphale</td><td>components for the anesthetic</td></tr><tr><td>0.1 % purified sodium hyaluronate</td><td>Santen</td><td>Hyalein</td><td></td></tr><tr><td>atipamezole hydrochloride</td><td>Zenoaq</td><td>antisedan</td><td></td></tr></tbody></table>

inducement and evaluation of a murine model of experimental myopia

Inducement and Evaluation of a Murine Model of Experimental Myopia

Murine model of myopia can be a powerful tool for myopia research because of the comparatively easy genetic manipulation. One way to induce myopia in animals is to put clear minus lenses in front of eyes for weeks (lens-induced myopia, LIM). However, extant protocols for inducement and evaluation vary from laboratory to laboratory. Here, we described a highly practical and reproducible method to induce LIM in mice using newly designed eyeglasses. The method fixes the lens stably in front of the mouse eye while allows the lens to be taken off for cleaning or topical drug administration. The phenotype is robust and efficient, and the variance is small. The method described here can be applied to mice right after weaning which extends the possible duration for experiments. We also gave technical advises for achieving reproducible results in refraction and axial length measurements. We hope the step-by-step protocol described here and the detailed article can help researchers perform myopia experiments with myopia more smoothly and make the data comparable across laboratories.

At first, check if all the necessary parts are prepared (Figure 1a). An example of a piece of assembled eyeglasses is shown in Figure 1b. Except for the main body of the frames and the nut, all other parts are disposable for each mouse. A set of completed eyeglasses is shown in Figure 1c. Change the angle between the two frames to fit the mouse with different ages.
<p class="jove_content" fo:keep...

In this protocol, we describe the full process of experimental myopia inducement in mice using newly designed eyeglasses and the technic needed for achieving stable and reproducible results in ocular parameter measurements.

Murine model of myopia can be a powerful tool for myopia research because of the comparatively easy genetic manipulation. One way to induce myopia in ...

inducement-and-evaluation-of-a-murine-model-of-experimental-myopia

Research

JoVE Journal

Neuroscience

This video demonstrates a method to induce ocular surface inflammation and meibomian gland dysfunction in a murine model. Stimulation of the mouse's immune system using an immunogen and later restimulation with the same immunogen promotes ocular surface inflammation, which causes plugging of meibomian gland secretion through neutrophil-produced aggNETs and leads to dry eye disease.

A Method to Induce Ocular Surface Inflammation in a Murine Model

In this video, an anesthetized rat undergoes an ocular procedure where magnetic beads are injected into the anterior chamber under a magnetic field to block the iridocorneal angle. This blockage obstructs the trabecular meshwork, preventing aqueous humor drainage and leading to increased intraocular pressure, damaging the retinal ganglion cells and optic nerve. This develops a glaucoma-like condition.

Experimental Glaucoma Induction via Iridocorneal Angle Obstruction In a Mouse Model

Source: Jiang, X., et al. Inducement and evaluation of a murine model of experimental myopia. J. Vis. Exp. (2019)This video demonstrates a procedure for inducing myopia in a mouse through the installation of a custom lens frame. The frame is secured to the exposed skull with dental adhesive, and concave lenses are inserted to shift the focal point behind the retina. This setup stimulates eyeball elongation leading to myopia.

Developing Myopia in a Mouse Model Through Lens-Induced Defocusing

Chronic ocular hypertension is induced using laser photocoagulation of the trabecular meshwork in mouse eyes. The intraocular pressure (IOP) is elevated for several months after laser treatment. The decrease of visual acuity and contrast sensitivity of experimental animals are monitored using the optomotor test.

A Laser-induced Mouse Model of Chronic Ocular Hypertension to Characterize Visual Defects

We present a method for inducing elevated intraocular pressure (IOP), by injecting magnetic microspheres into the rat eye, to model glaucoma. This leads to strong pressure rises, and extensive neuronal death. This protocol is easy to perform, does not require repeat injections, and produces stable long-lasting IOP rises.

Experimental Glaucoma Induced by Ocular Injection of Magnetic Microspheres

We demonstrate the effect of scleral crosslinking with riboflavin and UVA on an axial elongation rabbit eye. Axial elongation was induced in 13 day-old New Zealand rabbits (male and female) by suturing their right eye eyelids (tarsorrhaphy).

Scleral Cross-linking Using Riboflavin and Ultraviolet-A Radiation for Prevention of Axial Myopia in a Rabbit Model

Here, we present the mouse laser-induced choroidal neovascularization (CNV) protocol, an experimental model that re-creates the vascular hallmarks of neovascular age-related macular degeneration (AMD). Once mastered, it can reliably and effectively induce CNV as a model system to test various experimental measures.

A Mouse Model for Laser-induced Choroidal Neovascularization

Here, we present a protocol to induce ocular hypertension in the murine eye that results in the loss of retinal ganglion cells as observed in glaucoma. Magnetic microbeads are injected into the anterior chamber and attracted to the iridocorneal angle using a magnet to block the outflow of aqueous humour.

A Magnetic Microbead Occlusion Model to Induce Ocular Hypertension-Dependent Glaucoma in Mice

Chronic ocular hypertension is induced by applying a circumlimbal suture in rats and mice, leading to functional and structural deterioration of the retinal ganglion cells consistent with glaucoma.

A Model of Glaucoma Induced by Circumlimbal Suture in Rats and Mice

Here, we describe the use of spectral-domain optical coherence tomography (SD-OCT) to visualize retinal and ocular structures in vivo in models of retinal degeneration, glaucoma, diabetic retinopathy, and myopia.

In vivo Structural Assessments of Ocular Disease in Rodent Models using Optical Coherence Tomography

Ocular surface inflammation harms the ocular surface tissues and compromises vital functions of the eye. The present protocol describes a method to induce ocular inflammation and collect compromised tissues in a mouse model of Meibomian gland dysfunction (MGD).

Induction of Ocular Surface Inflammation and Collection of Involved Tissues

Learn to induce and evaluate lens-induced myopia in mice using head-mounted eyeglasses with standardized protocols. This method enables precise, reproducible measurements of refraction and axial length for ophthalmology research.

Inducement and Evaluation of a Murine Model of Experimental Myopia

Explore More Videos