Visual axis opacification after pediatric cataract surgery - An analysis of morphology and etiology.

PURPOSE: To investigate the morphological types and delineate the clinical and surgical variables associated with VAO in children undergoing pediatric cataract surgery. METHODS: We included 33 eyes of 28 children who developed clinically significant visual axis opacification (VAO) after congenital or developmental cataract surgery. All eyes underwent a comprehensive examination under anesthesia followed by a membranectomy to clear the visual axis. We classified VAO into three subgroups: fibrotic, proliferative, and combined morphologies. We reviewed and analyzed the retrospective data and the findings during membranectomy to identify the etiological variables associated with various morphologies of VAO. RESULTS: The median age at primary surgery was 7 (2-96) months. The median interval from primary surgery to the first documentation of VAO was 6 (1-22) months. Younger children developed VAO sooner than older children. VAO was fibrotic in 11 eyes (33%), proliferative in 18 eyes (54.5%), and combined in four eyes (12.12%). Most children with fibrotic VAO belonged to economically disadvantaged sections of society ( P = 0.04). CONCLUSION: Lower age at primary surgery was the predominant risk factor for the development of VAO. Besides primary posterior capsulotomy and adequate anterior vitrectomy, a strict adherence to anti- inflammatory measures and follow up in necessary to prevent the occurrence of VAO. A close follow-up facilitates early detection and management, which can prevent the onset of visually impairing amblyopia.

A pilot randomized clinical trial comparing muscle transplant versus hang back recession in extra-large angle exotropia.

PURPOSE: For extra-large angle exotropia (>60 prism diopters, PD), single-setting surgical alternatives are scarce; frequently, more than two muscle or two eye procedures are indicated. To evaluate the viability of single eye surgery, a current randomized comparative trial is undertaken. METHODS: Twenty adult patients with extra-large angle exotropia underwent a thorough orthoptic evaluation before being divided into two groups at random. Ten patients in group 1 underwent medial rectus resection (5.5-7.5 mm), followed by transplant-aided lateral rectus recession (effective length: 4-5.5 mm) (9 mm). In group two, ten different patients underwent medial rectus resection (5.5-7 mm), but this time, the lateral rectus recession (9 mm) was aided with a hang-back suture (5-7 mm). The two procedures were compared at baseline and six months post-operatively. RESULTS: There was no significant difference in the groups' median ages (P = .95). In groups one and two, the median corrections achieved were 81.00 (79.50-85.50) PD and 81.00 (79.75-86.50) PD, respectively. The differences in corrections were statistically insignificant (p = .99). In all patients, abduction limitation was frequently noted in the immediate post-operative period, which improved over time. In each group, there were two patients (>90 prisms) with residual deviation of at least 30 PD, for which the contralateral eyes were operated. CONCLUSIONS: The hang-back recession was as successful as muscle transplant procedure in correcting 80-90 PD of exotropia with notable clinical benefits and ease.

"Pinch and Stretch" technique to overcome ocular hypotony during scleral suturing of recti muscles.

During extraocular muscle surgery, an uneventful scleral suture pass is very essential. In presence of normal intraocular tension, the surgery is quite predictable and safe. However, in the presence of significant hypotony, it becomes challenging. Therefore, to mitigate complication rate in these cases, we have adopted a simple technique, that is, the "pinch and stretch" technique. The surgical steps of this technique are as follows: In eyes with significant ocular hypotony, the surgery is initiated with a routine forniceal/limbal peritomy, following which the muscle is sutured and dis-inserted. Using three tissue fixation forceps, the scleral surface is stabilized. Using first forceps, the surgeon rotates the globe toward themself from the muscle stump, and with the remaining two forceps, the assistant pinches and stretches the episcleral tissue in an outward and upward direction just beneath the intended marks. This creates a flat scleral surface with significant firmness. Sutures are passed over this rigid sclera and the surgery is completed without any complications.

Rectus muscle pseudo-adherence syndrome.

Purpose: To describe a clinical entity called "rectus muscle pseudo-adherence syndrome" following buckling surgery. Methods: A retrospective data review was undertaken to analyze the clinical profile of strabismus patients who had developed it following buckling surgery. Between 2017 and 2021, a total of 14 patients were identified. The demography, surgical details, and intraoperative challenges were reviewed. Results: The average age of the 14 patients was 21.71 ± 5.23 years. The mean pre-op deviation was 42.35 ± 14.35 prism diopters (PD) of exotropia, and the mean post-op deviation was 8.25 ± 4.88 PD of residual exotropia at 26.16 ± 19.53 months follow-up. Intraoperatively, in the absence of a buckle, the thinned-out rectus adhered to the underlying sclera with much denser adhesions along its margins. When there was a buckle, the rectus muscle adhered to the outer surface of the buckle again, but less densely, with marginal union into the surrounding tenons. In both scenarios, due to the absence of protective muscle coverings, the rectus muscles were naturally adsorbed onto the immediately available surface in the presence of active healing by the tenons. Conclusion: While correcting ocular deviations following buckling surgery, a false sense of an absent, slipped, or thinned-out rectus muscle is very much possible. This is due to active healing of the muscle with the surrounding sclera or the buckle in a single layer of tenons. This is the rectus muscle pseudo-adherence syndrome, where the culprit is the healing process and not the muscle.

Novel Inferior Oblique Muscle Y Splitting Procedure to Minimize the Anti-Elevation Syndrome: A Pilot Study.

Purpose: To describe novel Y splitting procedure of inferior oblique muscle to mitigate the anti-elevation syndrome. Methods: A pilot, prospective interventional study was undertaken to assess the effect of inferior oblique muscle Y-splitting in patients with unilateral 3+ or more overaction. To correct primary gaze hypertropia and the excyclotorsion, a Y-splitting procedure was performed (along with routine horizontal muscle surgery as per the deviation) in 14 subjects. The effect of surgery was assessed at baseline and at 6 months post-intervention. Results: The mean age of 14 subjects was 25.14±7.70 years. The mean pre-operative hypertropia, excyclotorsion and inferior oblique muscle over-action was 18.42±3.50 PD, 14.14±2.65 degrees, and +3.21±0.42 respectively. Following surgery, this was reduced to 1.57±1.74 PD of residual hypertropia (a net correction of 16.85±2.31 PD, p = 0.005), 3.85±1.46 degrees of residual excyclotorsion (a net correction of 10.28±1.72 degrees, p < 0.05), and +0.28±0.46 of residual inferior oblique over-action (a net correction ~+3) at the end of 6 months. Amongst fourteen patients, three patients still experienced residual/variable anti-elevation effect, and during the study period none of them experienced any adverse event and none of them required any additional surgeries. Conclusion: While anteriorizing the inferior oblique muscle to correct primary gaze hypertropia and the excyclotorsion, a novel "Y splitting" procedure can be followed to achieve the desired results with mitigated anti-elevation effect.

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.

Defining the Clinical Role of Swept-Source Anterior Segment Optical Coherence Tomography in Eyes Undergoing Strabismus Surgery.

Purpose: To describe the clinical role of swept-source anterior segment optical coherence tomography in extraocular muscle imaging in various strabismic conditions. Study Design: Prospective observational study. Participants: A total of 1104 extraocular muscles of 150 subjects were imaged. Normal eyes (640 muscles), eyes undergoing re-operation (240 muscles), paralytic strabismic eyes (16 muscles), non-paralytic strabismic eyes (20 muscles), post-traumatic strabismic eyes (64 muscles), eyes with thyroid disease (64 muscles), and other atypical cases (60 muscles) were imaged. In all cases, up to four recti muscles were evaluated in a given eye depending on the need. Results: The mean age was 38.15 ± 16.25 years. Overall, muscle insertion was identified in over 90% of the subjects. Apart from normal muscles (n = 860, 93.68%), the location was identified in previously operated eyes (n = 54, 90%), in traumatic muscle slippage (n = 2, 11.11%), in ocular coat ectasia (n = 11, 91.66%), in thyroid muscle hypertrophy, in operated scleral fixated intraocular lens with strabismus, and other challenging cases. In all circumstances, clinically useful information was obtained from the anterior 4-14 millimetres of the rectus muscle, which in turn helped in active surgical planning and overall management. Conclusion: The SS-ASOCT with its wider and deeper scanning abilities was able to locate the extraocular muscle insertion in a variety of strabismic conditions. Therefore, this tool can be used in the preoperative periods for optimal surgical planning and management.

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.

Animal and cadaver human eyes for residents' surgical training in ophthalmology.

In ophthalmology residency programs surgical training plays a vital role in creating confident and skillful surgeons. As almost all ophthalmic surgery needs microscope training, creating a well-taught environment for hand-eye coordination, ocular tissue handling, and anticipation of complications is essential. Wet lab training with animal or cadaver human eyes offers diverse possibilities. We conducted a thorough literature search on various databases to identify the existing literature on wet labs. The results revealed constructive efforts for training novice surgeons in all surgical ophthalmology subspecialties. Wet lab models were initially used only to practice cataract surgery; however, now various complex ocular procedures can be practiced. Ocular surface, corneal, iris, lenticular, scleral, vitreoretinal, extraocular, eyelid, and other adnexal surgeries were reproduced and mastered in many ways. Importantly, with repeated surgical practice, residents gained an increasing level of confidence with enhanced surgical accuracy. In addition, we propose a few novel techniques of various other procedures.

The high-pressure bleb.

A 45-year-old male presented with a slowly progressive, painless swelling in his right eye for the past 6 months. He had undergone an open globe injury repair 10 years back and an eventful cataract surgery 5 years back. The presenting visual acuity in the affected eye was perception of light with inaccurate projection of rays. The intraocular pressure was 44 mm Hg with advanced glaucomatous cupping. The swelling was identified to be a communicating sub-tenon cyst secondary to scleral wound dehiscence from secondary angle closure glaucoma. Wound re-suturing, cyst excision and diode laser cyclophotocoagulation was performed in a single sitting, with explained poor visual prognosis.

Cysticercosis in ophthalmology.

Cysticercosis is caused by Taenia solium, a cestode or tapeworm that preferentially affects the subcutaneous tissue, brain, muscle, and the eye. It is traditionally a disease of low socioeconomic regions, but large-scale population migration has made it a matter of global concern. Its ocular invasion is a potentially blinding disease. In the last two decades, there has been considerable discussion of cysticercosis; however, most comes from a limited number of case observations. Thus, to overcome this limitation, we summarize and analyze twenty years of medical literature (from 2000 to 2020) on cysticercosis in ophthalmology.

Goniotomy on Goat's Eye (GOGE) Model: To Improve Angle-based Surgery Skills of the Residents.

PURPOSE: To describe a realistic goat's eye model to aid in surgical training of ophthalmology residents for improvising skills in intraoperative gonioscopy and incisional goniotomy surgery. METHODS: This study provides a descriptive report explaining the step-by-step methodology for setting up a goat's eye model to train the ophthalmology residents in both intra-operative gonioscopy and incisional goniotomy. The goat's eyeball was prepared and mounted within the socket of a mannequin head. The mannequin head was tilted and microscope angulation was adjusted to allow adequate visualization of angle structures. Following intra-operative visualisation of angle structures through a Swan Jacob lens, incisional goniotomy was performed using a microvitreo-retinal blade on approximately 120° nasal angle. The model was found to produce reproducible results when tested on 22 trained residents. CONCLUSION: The Goniotomy on Goat's Eye (GOGE) model can provide a realistic and a relatively inexpensive tool for resident surgeons to develop bimanual coordination and enhance their surgical skills to perform effective intraoperative gonioscopy and incisional goniotomy surgery.

Clinical Role of Swept Source Anterior Segment Optical Coherence Tomography in Strabismus Re-Operation with Lost Surgical Details.

BACKGROUND: To characterize the diagnostic role of swept source anterior segment optical coherence tomography (SS-ASOCT) in strabismus re-operations with lost surgical details. METHODS: Patients presenting to our outpatient services for strabismus care from February 2020 to March 15th 2021 were systematically evaluated. Those willing to undergo re-operation were included in the study. A total of 30 patients were identified and out of this a total of 10 eyes of 10 patients with lost surgical details were finally included in the study. Demographic details, preoperative deviation, ocular findings, orthoptic measurements, detailed SS-ASOCT findings, intraoperative measurements, and post-operative outcomes were recorded. RESULTS: The mean age of 10 patients was 23.7±5.75 years. Seven were male and three were female. The mean pre-operative SS-ASOCT measured distance from angle to insertion was 8.90±1.85 mm and the mean intraoperative distance was 9.12±2.14 mm. A mean difference of 0.21±1.31 mm was noted, and this difference was statistically insignificant (paired t test, p = 0.57). In addition, SS-ASOCT unraveled novel signs to differentiate operated eyes from the un-operated eyes, and recessed muscle from the resected muscle. CONCLUSION: In strabismus re-operation with lost surgical details, the pre-operative SS-ASOCT can provide reliable muscle details with respect to its type of surgery and amount surgery.

A simple do-it-yourself model of phacoemulsification for resident training.

COVID-19 has immensely affected the training of ophthalmology residents; wet-lab training thus becomes of utmost importance. A simple cost-effective model for cataract surgery training of residents becomes the need of this hour. Hence, we aim to describe a new 'Do It Yourself' model with easily available material for beginners.

Study 3: Assessment of events during surgery on posterior polar cataracts using intraoperative optical coherence tomography.

Purpose: To describe the changes along nucleo-epinuclear and the opacity-capsular junction during hydrodelineation and the entire period of phacoemulsification using intraoperative optical coherence tomography (iOCT). Methods: A total of 12 eyes of 12 patients with clinically confirmed posterior polar cataract, who underwent cataract surgery by a single surgeon under the direct guidance of iOCT. The changes along nucleo-epinuclear junction and opacity-capsular junction during/following hydrodelineation and the changes along the opacity-capsular junction following nucleus removal, capsular changes before the opacity removal, and its dynamic changes throughout the surgical procedure were studied. Results: The mean age of patients was 48.25 ± 7.89 years. Eight of them were males and the right eye was operated in seven patients. With regular hydrodelineation, optimal separation of the nucleus-epinuclear layer was evident in 11 patients. Once a golden ring is achieved through the hydro procedure, then repeated attempts can be performed within it to decrease the chances of capsular damage. Fracture of the posterior opacity with tension over the underlying capsule (n = 1), inadvertent hydro dissection while performing hydrodelineation (n = 1), continuous posterior capsular billowing (n = 2), and posterior capsular ruptures (n = 2) were encountered in this observation with even well-judged surgical maneuvering. Conclusion: iOCT provides a better understanding of real-time changes along different layers of the human lens during posterior polar cataract surgery. The observations obtained here are likely to help in minimizing inadvertent complications in the future.

The Emerging Role of Anterior Segment Optical Coherence Tomography in Cataract Surgery: Current Role and Future Perspectives.

Modern-day cataract surgery has achieved equivalence with refractive surgery, thus requiring surgeons to perform all possible pre-emptive exercises to mitigate intraoperative complications. In this direction, we possess a tremendous amount of technology to understand the preoperative status of the lens. Anterior segment optical coherence tomography (ASOCT) is one such tool, which has played a distinctive role in imaging various forms of cataracts. In this review, we critically analyse the practical role of ASOCT in the preoperative and intraoperative periods from a cataract surgeon's perspective. After a thorough literature assessment, it was substantiated that the cross-sectional imaging ability of ASOCT can demonstrate delicate anatomical and pathological lenticular changes in a visually and clinically comprehensible way. The objective grading of immature cataracts to intralenticular and posterior capsular details in mature/white, posterior polar, traumatic and other forms of cataracts paves the way for various practical innovations as and when required. Hence, preoperative more than intraoperative ASOCT-derived lenticular knowledge is of immense help in careful surgical planning, with improved complication rates.

Trabeculectomy on Animal Eye Model for Resident Surgical Skill Training: The Need of the Hour.

Purpose: To describe a goats' eye training model for teaching of trabeculectomy and releasable suture techniques for Ophthalmology residents. Methods: A descriptive report explaining the methodology for setting up a goats' eye wet-lab model for teaching trabeculectomy for Ophthalmology residents. It details the approaches to eyeball preparation, steps of surgery, application and release of two representative types of 'releasable sutures' in a step-by-step manner. Conclusion: A systematic approach using goats' eye model to teach trabeculectomy and releasable suture techniques can enhance residents' understanding, confidence and expertise to operate upon human eyes.

Mitigation of traumatic blepharoptosis with "central levator tuck": A novel approach in upper eyelid repair.

PURPOSE: Complex upper eyelid lacerations can present to the emergency department after a myriad of trauma. The goal of the surgical repair is anatomical and functional recovery along with symmetrical cosmesis. Despite meticulous surgery, post traumatic blepharoptosis may develop. We describe an additional step during upper eyelid laceration repair to help mitigate the development of traumatic blepharoptosis. METHODS: Patients with traumatic eyelid laceration without head injury, globe injury or associated orbital fractures, who were planned for a primary upper eyelid repair were included. Intraoperatively, wound margins and tissues were identified to establish anatomical continuity. After the LPS muscle was reinserted onto the tarsus, a single, central suture LPS plication - the "central levator tuck" was performed. This helped in improving the muscle action as well as strengthening its reattachment onto tarsus. RESULTS: Four cases underwent laceration repair with this modified technique. The nature of eyelid injury, surgical technique, and the outcome at 6 months is described. Three patients had a successful outcome, whereas one patient developed early scarring which reduced with scar therapy over time. CONCLUSION: We describe a simple and effective "central levator tuck" technique for traumatic eyelid laceration repair with optimal functional and cosmetic outcome while reducing the development of blepharoptosis in four patients.

Optical coherence tomography angiography in neuro-ophthalmology: Current clinical role and future perspectives.

Optical coherence tomography angiography (OCTA) is a noninvasive, depth-resolved imaging tool for the appraisement of retinal vascular changes. Since its introduction, the understanding of diabetic retinopathy, age-related macular degeneration, central serous retinopathy, and other diseases has been enriched on many fronts. Its dyeless imaging property maps retinal as well as deeper choroidal vasculature in quick succession with good reproducibility. Hence, it can play an important role in the diagnosis and management of optic nerve-related diseases as well. A detailed literature review for its role in nonarteritic anterior ischemic optic neuropathy, papilledema, optic disc drusen, papillitis, hereditary optic neuropathies, central nervous system diseases, and others highlights its role. The whole spectrum of neuro-ophthalmological diseases shows consistent peripapillary and macular capillary changes with structural and functional correlation. The superficial and deeper retinal and choroidal vasculatures are affected depending on the nature of the disease process. Hence, OCTA positions itself as a useful, noninvasive tool in the armamentarium of a neuro-ophthalmologist in future; however, there are several limitations of the OCTA with respect to its technical abilities in challenging neuro-ophthalmic cases. Therefore, future research should be directed to enhance the technical capabilities of OCTA and to determine the more precise role of it in the prognosis of neuro-ophthalmic diseases.