Kanwar Mohan

Persistent Corneal Edema after Collagen Cross-Linking for Keratoconus

PURPOSE To present a new complication of persistent corneal edema after collagen cross-linking (CXL) in keratoconus patients. DESIGN Retrospective case series of postoperative corneal edema after CXL. METHODS study population: All patients who underwent CXL treatment with subsequent corneal edema. Patients with stromal haze were excluded. intervention: The CXL treatments used the Dresden protocol with corneal thickness of more than 400 μm after epithelium was removed. main outcome measure: The resolution of corneal edema after surgery. RESULTS Postoperative corneal edema was identified in 10 (2.9%) of 350 patients who were followed up for a mean of 14 ± 4 months. The edema started on postoperative day 1 (10/10) and increased for 3 weeks. Additional findings included: deep vascularization (2 eyes; 20%), iris atrophy (6 eyes; 60%), pigment dispersion (5 eyes; 50%), persistent epithelial defect (3 eyes; 30%), and infectious keratitis (1 eye; 10%). Specular microscopy was unsuccessful, but the fellow untreated eyes had normal endothelial counts. Intraocular pressure and lenticular evaluations were normal. Corneal edema improved in 4 patients and resolved in 1 patient. In these 5 patients, the logarithm of the minimal angle of resolution best-corrected visual acuity was 0.5 ± 0.18. Penetrating keratoplasty was offered to 5 patients when improvement plateaued at 3 months, but only 2 patients underwent penetrating keratoplasty. CONCLUSIONS CXL is a safe and effective procedure with few known side effects. This case series reports the possibility of corneal endothelial damage with visually significant corneal edema after CXL treatment. Based on the extent of endothelial damage, patients may require penetrating keratoplasty.

Successful occlusion therapy for amblyopia in 11- to 15-year-old children.

PURPOSE To investigate the effectiveness of full-time occlusion therapy in treating amblyopia in 11- to 15-year-old children and to determine its lasting results. PATIENTS AND METHODS Fifty-five compliant children 11 to 15 years old who had amblyopia were treated with full-time (during all waking hours) occlusion of their good eye until no further improvement in the visual acuity of their amblyopic eye was observed on 3 consecutive monthly follow-up examinations. After this, part-time (4 hours per day) occlusion therapy was used randomly in 24 of 55 patients for 3 to 6 months for maintenance of the final visual acuity. Snellen visual acuity and its logMAR equivalent were recorded before treatment, at the cessation of full-time occlusion therapy, and on the most recent examination. RESULTS All 55 of the patients had improved visual acuity after treatment. The mean improvement was 0.46 logMAR unit (4.6 Snellen lines). Thirty-two of the patients had a mean follow-up of 17.6 months after the cessation of full-time and maintenance occlusion therapy. Twenty-nine (91%) of the 32 patients maintained improved visual acuity, whereas 3 (9%) exhibited a regression in visual acuity. Maintenance occlusion therapy did not have a significant stabilizing effect on the improved visual acuity. CONCLUSION Compliant, full-time occlusion effectively improves acuity in children 11 to 15 years old who have amblyopia due to strabismus, anisometropia, or both. Most older patients have lasting improvement with or without maintenance patching.

Visual acuities after levodopa administration in amblyopia.

PURPOSE To investigate the effect of the augmentation of levodopa with part-time and full-time occlusion on visual acuity and to determine its late results in amblyopia. METHODS Seventy-two patients with amblyopia were prospectively studied and randomly distributed into groups A, B, and C consisting of 24 patients each. Group A patients received levodopa alone, group B received levodopa and part-time (3 hours/day) occlusion, and group C received levodopa and full-time (during all waking hours) occlusion of the dominant eye. Levodopa 0.50 mg/kg body weight, with a 25% fixed dose combination of carbidopa, was administered orally three times a day for 7 weeks. Snellen visual acuity and its logMAR equivalent were recorded before treatment, at weeks 1, 3, 5, and 7 after starting treatment, and every 6 weeks for 1 year after the completion of treatment. RESULTS Fifty-three (74%) of the 72 patients had an improvement in visual acuity after treatment. Forty-four of the 53 patients with improved visual acuities completed 1-year post-treatment follow-up. Twenty-three (52%) of the 44 patients had a regression in visual acuity. CONCLUSION The augmentation of levodopa with part-time or full-time occlusion does not enhance the recovery of vision in amblyopia. Improved visual acuity after levodopa administration persists at least 1 year in almost half of patients after cessation of treatment. Addition of full-time occlusion to levodopa helps maintain improved visual acuity for a longer duration compared to levodopa alone or combined with part-time occlusion.

Differences in epidemiological and clinical characteristics between various types of Duane retraction syndrome in 331 patients.

PURPOSE To determine the differences in various epidemiologic and clinical characteristics among types I, II, and III of unilateral Duane syndrome and between unilateral and bilateral Duane syndrome. METHODS A retrospective chart review of 331 patients with the Duane syndrome (291 unilateral and 40 bilateral) was performed. Various characteristics studied included sex, age at presentation, laterality, manifest primary position horizontal deviation, upshoot and downshoot, amblyopia, and associated ocular and systemic abnormalities. RESULTS Unilateral types I and III Duane syndrome were more common in the left eye and in female patients, whereas type II had no such predilection. The mean age at presentation was significantly greater in type III patients. Type I patients had an almost-equal frequency of esotropia and exotropia, type II had exotropia, and type III had exotropia more commonly than esotropia. The upshoots and downshoots were more common in types II and III. There was no difference in amblyopia among various types of Duane syndrome. Associated ocular abnormalities were more common in types I and III, and systemic abnormalities were more common in type I. A manifest primary position horizontal deviation was more common in bilateral Duane syndrome. Exotropia was more common in unilateral cases, whereas esotropia was more common in bilateral cases. CONCLUSION Unilateral types I, II, and III Duane syndrome differ in the mean age at presentation, primary position horizontal deviation, upshoot and downshoot, and associated ocular and systemic abnormalities. Bilateral Duane syndrome differs from the unilateral only in the primary position horizontal deviation.

Vertical Rectus Recession for the Innervational Upshoot and Downshoot in Duane's Retraction Syndrome

PURPOSE To report the results of recession of the vertical rectus muscle for the innervational upshoot and downshoot in Duanes retraction syndrome. METHODS Ten patients who had Duanes retraction syndrome with innervational upshoot or downshoot underwent recession of the superior and inferior rectus muscle for the upshoot and downshoot, respectively. This procedure was combined with recession of the lateral rectus muscle(s) for exotropia in 6 patients and for the mechanical upshoot-downshoot in one patient. Postoperatively, the effects of surgery on the upshoot/downshoot, and horizontal and vertical deviation in the primary position were recorded. Average follow-up period was 1.2 years. RESULTS Following surgery, the innervational upshoot/downshoot was eliminated in all patients. Mean vertical deviation in the primal position in 6 patients was reduced from 21.2 to 2.5 prism diopters and none of them developed a consecutive vertical imbalance. Four patients did not have a vertical deviation in the primary position preoperatively and one of them developed 10 prism diopters hypotropia following recession of the superior rectus muscle. CONCLUSIONS Recession of the superior and inferior rectus muscle is a safe and effective treatment for the innervational upshoot and downshoot, respectively, in Duanes retraction syndrome.

Unilateral traumatic aphakia in children: role of corneal contact lenses.

Twenty-eight children below ten years of age with unilateral traumatic aphakia were fitted with hard corneal contact lenses. Visual acuity of 6/12 or better was achieved in 68% of the cases. Patients who were above seven years of age at the time of injury, and those fitted with contact lenses within eight months of trauma, were found to have better chances of recovering normal binocular functions.

Factors Predicting Upshoots and Downshoots in Duane's Retraction Syndrome

PURPOSE Factors predicting mechanical and innervational types of upshoots and downshoots in Duanes retraction syndrome were evaluated. METHODS This retrospective study evaluated upshoots and downshoots in 196 patients (222 eyes) with Duanes retraction syndrome seen between January 1990 and July 2001. On the basis of the clinical characteristics, upshoots and downshoots were classified as mechanical type, innervational type, or both. Factors potentially predicting the upshoot-downshoot phenomenon that were studied included patient age, type of Duanes retraction syndrome, horizontal strabismus, and vertical tropia in the primary position of gaze. RESULTS Upshoots and downshoots were present in 39% of the eyes. The mechanical type was more common than the innervational type (26% vs 12%). Overall, upshoots and downshoots were statistically significantly more common in type III Duanes retraction syndrome, with exotropia, and with vertical tropia in primary position. Patient age had no correlation with upshoots or downshoots. Both types of upshoots and downshoots were significantly more common in type III Duanes retraction syndrome. A statistically significant association was found between exotropia and the mechanical type, and between vertical tropia in primary position and the innervational type. CONCLUSIONS All patients with type III Duanes retraction syndrome, exotropia, and vertical tropia in the primary position of gaze should be examined for upshoots and downshoots. One should look specifically for the mechanical type when there is exotropia and for the innervational type when there is a large vertical tropia in the primary position of gaze.

Cyanoacrylate tissue adhesive augmented tenoplasty: a new surgical procedure for bilateral severe chemical eye burns.

PURPOSE To report on cyanoacrylate tissue adhesive augmented tenoplasty, a new surgical procedure for bilateral severe chemical eye injuries. METHODS A 26-year-old man presented with bilateral severe (grade IV) chemical burns involving the eye, periorbital tissues, face, and neck. Despite adequate medical therapy, corneal, limbal, and scleral ulceration progressed in both eyes. Secondary Pseudomonas keratitis necessitated therapeutic penetrating keratoplasty in the right eye. Tenoplasty and glued-on rigid gas permeable contact lens were unsuccessful to arrest progression of corneolimboscleral ulceration in the left eye. We applied n-butyl cyanoacrylate tissue adhesive directly on the ulcerating corneal, limbal, and scleral surface to augment tenoplasty. RESULTS The left ocular surface healed with resultant massive fibrous tissue proliferation and symblepharon on the nasal side. Ocular surface rehabilitation resulted in a vascularized leukomatous corneal opacity with upper temporal clear cornea. The patient achieved visual acuity of 6/36 in the left eye. CONCLUSION We suggest that cyanoacrylate tissue adhesive-augmented tenoplasty can be undertaken to preserve ocular integrity and retain visual potential in a severe chemical eye injury.

Optimal dosage of cyclopentolate 1% for cycloplegic refraction in hypermetropes with brown irides.

To find the optimal dosage of cyclopentolate 1% for cycloplegic refraction in hypermetropes with brown irides, we investigated the difference in cycloplegic auto-refractions obtained after one, two, and three instillations in the same patient. The mean hypermetropia found after three instillations was statistically significantly more compared to that found after one instillation. There was no statistically significant difference in the mean hypermetropia between two and three instillations. There was no significant effect of gender, age, and the presence and type of horizontal deviation. These observations suggest that two drops of cyclopentolate 1% 10 min apart are sufficient for cycloplegic refraction in hypermetropes.

Development of refractive accommodative esotropia in children initially diagnosed with pseudoesotropia

PURPOSE To determine the clinical characteristics of children with pseudoesotropia who later develop refractive accommodative esotropia. METHODS We retrospectively reviewed the records of consecutive patients diagnosed with pseudoesotropia from 2003 to 2010. Inclusion criteria included age 3 years or younger at the time of diagnosis, history of strabismus, verifiable positive or negative family history of strabismus, hypermetropia detected with atropine refraction, prism and cover test measurements performed with and without refractive correction at follow-up visits, and a minimum follow-up of 1 year. RESULTS A total of 51 children met inclusion criteria (average age, 1.48 ± 0.79 years; range, 3-36 months; mean follow-up, 2.9 years). Refractive accommodative esotropia developed in 15.7% of the children at a mean age of 2.78 ± 1.06 years. It developed in 53.9% of the children with pseudoesotropia who had >1.50 D of hypermetropia compared to 2.6% of those who had ≤ 1.50 D hypermetropia (P = 0.0001). A positive family history of strabismus (P = 0.193) and initial age at presentation with pseudoesotropia (P = 0.571) were not predisposing factors. CONCLUSIONS Children aged ≤ 3 years diagnosed with pseudoesotropia should undergo cycloplegic refraction. If >1.50 D hypermetropia is detected, patients should be monitored for the development of refractive accommodative esotropia.