Gonioscopy and Angle-Based Glaucoma Surgical Training on Human Eyes in the Wet Lab.

PRCIS: Human corneoscleral rims provide a low cost model and resource to enhance angle based glaucoma surgical training skills. PURPOSE: To understand the feasibility, utility, and efficacy of a low-cost model for performing anterior chamber angle gonioscopy and micro-surgery on human corneoscleral tissues in wet lab on resident skill enhancement. METHODS: Post-keratoplasty residual corneoscleral rims and/or the expired donor corneoscleral buttons were included for the purpose of this study. Initially, inverted rims were used to demonstrate the basic angle anatomy on a slit lamp bio-microscope. Central hazy cornea was then replaced with an artificial cornea and an artificial anterior chamber to simulate indirect gonioscopy, direct gonioscopy, goniotomy, and other angle-based surgeries. Direct gonioscopy and goniotomy exercises (as a means to simulate intraoperative gonioscopy and other angle-based surgeries respectively) were evaluated quantitatively, and the rest qualitatively. RESULTS: A total of 65 residents were included in the exercise. The mean age was 26.69±1.74 years. Amongst these, 55 ophthalmology residents performed the basic examination, that is, slit lamp mounted angle anatomy examination (n=55) and artificial chamber mounted indirect gonioscopic examination through artificial cornea (n=55). In the second exercise, 10 glaucoma fellows performed the direct gonioscopic and the goniotomy exercises on artificial chamber. The fellows demonstrated a statistically significant improvement in interpretation and surgical skill enhancement concurrent with reduction in time taken with increasing number of attempts ( P <0.05). In the third simulation exercise, micro-stent placement within the Schlemm's canal, subconjunctival space, and the suprachoroidal space was re-produced successfully on multiple occasions. CONCLUSIONS: The residual human corneoscleral rims proved to be an important resource for teaching both the basic examination skills and those required for transitioning to advanced intraoperative gonioscopy and goniotomy skills. These low cost, easy to adapt models can be incorporated within the curriculum for improved glaucoma training of both the residents and the glaucoma fellows.

Simulation of complex strabismus surgical procedures on goat eyes.

PURPOSE: To describe the possibility of complex strabismus surgical simulation on goat eyes. METHODS: The goat eyes were procured from local slaughterhouse with retained extra ocular muscle tissues. The obtained eyes were inspected for globe integrity, muscle quality, muscle length, and the surrounding teno-conjunctival layers. The included eyes were then segregated for surgical simulation based on their insertion and orientation (as oblique or recti), and they were mounted on a mannequin head, with a fixation suture at free end to simulate the resting tension. Additionally, as per necessary, extra muscles were also transplanted along desired sites to simulate human extra ocular muscle anatomy. RESULTS: The inferior oblique, superior oblique, and all other four recti were successfully simulated in varying proportions in more than 50 eyes. Primarily, by simulating the lateral rectus, inferior rectus, and the inferior oblique muscle, staged weakening procedures of inferior oblique were successfully practiced (Fink's recession, Park's recession, Elliot and Nankin procedure, total anterior positioning, and antero-nasal trans-position or Stager's procedure). Similarly, by simulating superior rectus, inferior rectus, lateral rectus, and the medial rectus muscles, half width transposition, full width transposition, and other complex procedures were practiced (Knapp's procedure, augmented Knapp's, Nishida's procedure, Faden operation, and Y splitting procedure). Furthermore, by simulating superior oblique and the superior rectus muscles, superior oblique tuck, posterior tenectomy, loop tenotomy, and Harada Ito procedures were successfully practiced. CONCLUSIONS: On goat eyes, the complex strabismus surgical procedures can be successfully simulated and practiced after re-organizing the existing muscles in different patterns.

Traumatic avulsion of the globe with optic nerve transection: an unusual presentation.

Complete globe extrusion, whether traumatic or spontaneous, is a rare clinical entity and if associated with optic nerve avulsion, it has a worse visual outcome, though repositioning of the globe may be attempted. We report a case of road traffic accident, wherein the patient presented with an extrusion of the globe, along with a complete transection of the optic nerve, about 4 cm from the optic nerve head, with only a residual attachment to the orbital rim via the unsevered lateral conjunctival flap, where the enucleation was completed and the conjunctiva was sutured.

Extraocular muscle surgery on goats' eye: An inexpensive technique to enhance residents' surgical skills.

Hands-on resident surgical training for various ocular procedures is essential to impart good surgical skills to the budding ophthalmologists. Here in this report, we demonstrate a simple and inexpensive technique of performing extraocular muscle surgery on goats' eye. These animal eyes possess soft tissue resemblance to that of human eyes to a greater extent in terms of scleral rigidity, muscle elasticity, its width, thickness, and its insertion onto the sclera. Therefore, rectus muscle recession, resection, and plication surgeries can be performed repeatedly to improve an individual's orientation and practical experience before performing the procedure on human eyes.

Retinal Arteriovenous Malformation Assessment Using Swept-Source OCT Angiography.

Swept-source optical coherence tomography angiography (SS-OCTA) is a promising new imaging modality for assessing retinal and choroidal vasculature. Faster scanning speed, large number of A-scan acquisition, and enhanced depth penetration has enhanced the detailed analysis of retinal layers. The authors discuss SS-OCTA features of a rare case of retinal arteriovenous malformation. Image analysis revealed the anomalous large-caliber vessels occupying up to the entire retinal thickness with associated echolucent changes in the inner retinal layers surrounding the retinal vessels, along with disruption of the outer retinal layers, including the inner/outer segments of photoreceptors beneath the large tortuous vessels outside the foveola in absence of any capillary nonperfusion areas or lack of significant macular edema. At the fovea, the outer retinal layers were intact due to a smaller caliber and less-deep extension of the anomalous vessels. [Ophthalmic Surg Lasers Imaging Retina. 2018;49:216-219.].