Crescentic Tuck in Lamellar Keratoplasty-A Novel Technique in a Case of Advanced Pellucid Marginal Corneal Degeneration.

PURPOSE: To describe a new surgical technique "crescentic tuck in lamellar keratoplasty" for the management of advanced pellucid marginal corneal degeneration (PMCD). METHODS: A 45-year-old man with advanced PMCD and maximal thinning in the inferior juxtalimbal periphery underwent a crescentic lamellar keratoplasty in the right eye. Best-corrected visual acuity was 6/60 with no further improvement because of severe irregular astigmatism. Thinnest pachymetry in the peripheral cornea was 280 µm. Peripheral crescent-shaped lamellar corneal dissection of 3.5-mm width was performed, and an intrastromal pocket was fashioned from 4 to 8 O'clock, extending beyond limbus. A crescent-shaped donor corneal button of 3.5-mm width was denuded of its endothelium and beveled in inferior periphery to create a flange. The flange was tucked into the peripheral scleral pocket. The donor graft was secured to the host bed using 10-0 nylon interrupted sutures. RESULTS: Donor cornea integrated with the host bed over time and best spectacle-corrected visual acuity at 1 year improved to 6/9 with -1.25/-3.5 D × 90°. The simK (simulated keratometry) changed from 41.6/56.3 diopters (D) to 45.1/50.6 D. The astigmatism reduced from 14.6 D to 5.5 D. CONCLUSION: Crescentic tuck in lamellar keratoplasty provides good apposition of the donor lenticule and tectonic support to the peripheral thin cornea while preserving the peripheral limbal stem cells. Additionally, there is a significant reduction in the astigmatism, resulting in visual improvement.

Evaluation of pattern electroretinogram in retinal vein occlusion treated with intravitreal triamcinolone acetonide.

PURPOSE: To evaluate pattern electroretinogram (pattern ERG) and anatomical changes in optical coherence tomography (OCT) in acute retinal vein occlusion with macular oedema after intravitreal triamcinolone acetonide (IVTA) injection. METHODS: In this prospective interventional study, 20 patients with acute retinal vein occlusion (branch and central) of less than 1 month duration were evaluated for pattern ERG, best-corrected visual acuity (BCVA), central macular thickness on OCT, and contrast sensitivity (CS) before and 1, 6 and 12 weeks after 1 mg IVTA injection. RESULTS: The amplitude of P50 wave (pattern ERG) improved from 3.01 ± 1.22 to 3.56 ± 1.29 µv, mean logMAR BCVA improved from 1.10 ± 0.60 to 0.69 ± 0.45, and CS improved from 0.45 ± 0.41 to 0.79 ± 0.29; mean central macular thickness (CMT) decreased from 515.35 ± 202.83 to 358.35 ± 135.4µ at 12 weeks. All the values were statistically significant (p value < 0.001). CONCLUSION: IVTA injection in acute retinal vein occlusion with macular oedema results in electrophysiological (pattern ERG) improvement in addition to anatomical (OCT) improvement.

Pattern ERG in central serous retinopathy.

BACKGROUND: To evaluate the pattern electroretinogram (PERG) in central serous retinopathy. METHODS: In this prospective study, 20 patients with recent onset (<6 weeks) unilateral CSR were studied with the fellow eye acting as control. BCVA, psychophysical parameters, FFA, OCT, flash and pattern ERG were evaluated. RESULTS: The mean P50 amplitude in the affected eye at presentation was 2.36 ± 0.8 µv compared to 3.24 ± 0.85 µv in the normal eye. At 12 weeks, the mean P50 amplitude in the affected eye was 3.16 ± 0.88 µv compared to 3.63 ± 0.82 µv in the normal eye. The reduction of 27 % in P50 amplitude even after recovery was statistically significant (P < 0.001). A reduction of 19.77 % in the amplitude of N95 wave in the affected eye compared to the normal eye was seen, which was statistically significant (P < 0.001). In the affected eye, there was statistically significant improvement in the psychophysical tests at 12 weeks. CONCLUSIONS: This study reveals that P50 component of the PERG is reduced in cases of CSR, indicating functional disturbance of the macular photoreceptors. A normal flash ERG indicates that pathology is electrophysiologically localised to macula without affecting general retina. Residual deficit in the PERG explains poor quality of vision in spite of normal anatomical apposition and quantitative 6/6 visual acuity.

Comparative evaluation of higher-order aberrations and corneal asphericity between wavefront-guided and aspheric LASIK for myopia.

PURPOSE: To compare visual outcome, higher-order aberrations, and corneal asphericity (Q value) between wavefront-guided and aspheric LASIK for myopia and myopic astigmatism. METHODS: Forty patients were randomly selected to receive wavefront-guided LASIK (wavefront-guided group) or aspheric LASIK (aspheric group) (40 eyes of 20 patients in each group) using the Technolas 217z excimer laser platform (Bausch & Lomb, Rochester, NY). Flaps were created using the Zyoptix XP microkeratome (Bausch & Lomb). Preoperative and postoperative evaluation included uncorrected distance visual acuity (UDVA), corneal topography, wavefront aberrometry, and contrast sensitivity. Minimum follow-up period was 6 months. RESULTS: At 6 months postoperatively, the aspheric group had significantly better UDVA (logMAR 0.04 ± 0.04 [Snellen 20/16] [range: -0.079 to 0.000]) and lower mean residual spherical error (+0.10 ± 0.52 diopters [D] [range: -1.12 to 1.25 D]) than the wavefront-guided group (logMAR UDVA 0.00 ± 0.07 [range: -0.079 to 0.176]; MRSE -0.35 ± 0.47 D [range: -1.5 to 0.62 D]) (P = .003 and < .001, respectively). Mean change in higher-order aberration root mean square at 6 months postoperatively (6-mm pupil) was 0.16 ± 0.17 µm after aspheric LASIK and 0.27 ± 0.28 µm after wavefront-guided LASIK (P = .02). Aspheric LASIK induced minimal change in spherical aberrations postoperatively (0.03 ± 0.12 µm, P = .09), unlike wavefront-guided LASIK (0.23 ± 0.17 µm, P < .01). Change in Q value was significantly less in the aspheric group (0.53 ± 0.31) than the wavefront-guided group (0.91 ± 0.30) (P < .01). The aspheric group had significant improvement in contrast sensitivity at all spatial frequencies (P < .01), whereas the wavefront-guided group showed a slight decrease at higher spatial frequency (18 cycles per degree). CONCLUSIONS: Aspheric LASIK induced significantly less change in higher-order aberrations and maintained corneal asphericity better than wavefront-guided LASIK. The visual outcome and contrast sensitivity was better in the aspheric group at 6 months postoperatively.

Ocular manifestations in renal diseases.

The eyes and kidneys are the targets for end-organ damage in multiple pathologies. Both these organs develop during the same embryonic stage around the fourth to sixth week of gestation, thus sharing a strong correlation between both eye and kidney diseases. Both the eyes and kidneys can be the target of the systemic disease process; however, the eyes can also be affected as a consequence of renal disease or its treatment. Risk factors such as diabetes, hypertension, and smoking are commonly shared between kidney and eye diseases. Ocular manifestations can be predictive of renal disease, and/or patients with renal disease are at higher risk for developing ocular manifestations. Various congenital anomalies of the eyes and kidneys can also present as an oculorenal syndrome. This article summarizes the ocular pathology, which can be seen in renal diseases.

Results of corneal collagen cross-linking in pediatric patients.

PURPOSE: To evaluate the safety and efficacy of corneal collagen cross-linking (CXL) in the treatment of keratoconus in pediatric patients. METHODS: Epithelium-off CXL using the standard protocol was performed in 15 eyes from 15 patients (age range: 10 to 15 years) with moderate keratoconus in 1 eye and advanced disease in the fellow eye. Principal outcomes included uncorrected and corrected distance visual acuity (CDVA), refraction, and topography-derived outcomes of maximum and average keratometry (K). RESULTS: Mean uncorrected distance visual acuity improved significantly from 1.00 ± 0.30 (20/200) to 0.72 ± 0.29 (20/100) logMAR (P=.035) and mean CDVA from 0.56 ± 0.21 (20/70) to 0.30 ± 0.15 (20/40) logMAR (P=.003) at the end of 12 months. Mean change in apical K (1.01 ± 2.40 diopters) was also significant (P=.004). No significant complications were noted. CONCLUSIONS: Corneal collagen CXL was found to be safe and effective in the first 12 months for keratoconus in children with similar initial efficacy as in adults in terms of improvement in visual and topographic outcomes.

Management of neurovascular emergencies with ophthalmic manifestations.

Patients with neurovascular disorders sometimes approach the ophthalmologists with mild ophthalmic clinical features such as conjunctival congestion, slowly progressive proptosis, lateral rectus palsies and at other times with ophthalmic emergencies like sudden increase in proptosis, ophthalmoplegia, diplopia, and ptosis before the onset of neurological manifestations which may be life-threatening if not detected in time. The aim of this article is to focus on ophthalmic manifestations of neurovascular emergencies and role of ophthalmologists in its management. In this communication, to make the ophthalmologist aware of clinical presentations, the imaging modality of choice, diagnostic features, medical and interventional treatments. We have searched PubMed, Web of Science, Google Scholar and reviewed some of the commonly encountered neurovascular emergencies with ocular manifestations such as carotid-cavernous fistula, cerebral venous sinus thrombosis, cerebral artery aneurysms, arterio-venous malformations.

Comparison of Plusoptix S12R photoscreener with cycloplegic retinoscopy and autorefraction in pediatric age group.

Purpose: To compare refractive measurements of noncycloplegic photoscreener Plusoptix S12R with cycloplegic retinoscopy, noncycloplegic autorefractor, and cycloplegic autorefractor in children. Methods: The study population (200 eyes of 100 children) was divided into two groups: Group 1 (age 3-7 years) and Group 2 (age 8-15 years). In Group 1, Plusoptix was compared with cycloplegic retinoscopy. In Group 2, Plusoptix was compared with cycloplegic retinoscopy and autorefraction. The second group was made because the younger group was found to be uncooperative for autorefraction. Paired t-test and Pearson's correlation were used for statistical analysis. Results: The mean difference in sphere (DS), spherical equivalent (DSE), and cylinder (DC) between cycloplegic retinoscopy and Plusoptix in Group 1 was 0.68 ± 0.55 (P < 0.001), 0.77 ± 0.61 (P < 0.001), and 0.18 ± 0.28 (P < 0.001), respectively. In Group 2, DS, DSE, and DC between cycloplegic retinoscopy and Plusoptix were 0.86 ± 0.49 (P < 0.001), 0.97 ± 0.51 (P < 0.001), and 0.23 ± 0.28 (P < 0.001); between cycloplegic autorefractor and Plusoptix were 0.69 ± 0.47 (P < 0.001), 0.74 ± 0.49 (P < 0.001), and 0.10 ± 0.31 (P = 0.002); and between noncycloplegic autorefractor and Plusoptix were - 0.25 ± 0.39 (P < 0.001), -0.19 ± 0.41 (P < 0.001), and 0.11 ± 0.31 (P < 0.001), respectively. Pearson's correlation coefficients of S, SE, and C between Plusoptix and cycloplegic retinoscopy were 0.948, 0.938, and 0.924 in Group 1 and 0.972, 0.972, and 0.946 in Group 2, and these values were statistically significant. Bland-Altman plots showed good agreement between cycloplegic retinoscopy and Plusoptix in both groups. Plusoptix gave axis values within 10° of cycloplegic retinoscopy in 81.56% of eyes in Group 1 and in 71.44% of eyes in Group 2. Conclusion: Plusoptix photoscreener can be used for prescription of axis of cylinder in children; however, other refractive measurements must be refined by cycloplegic retinoscopy.

Pigment dispersion syndrome associated with spontaneous subluxation of crystalline lens.

Pigment dispersion syndrome (PDS) is an ocular condition characterized by a dispersion of iris pigment throughout the eye. This pigment is deposited in a characteristic manner on the corneal endothelium as Krukenberg's spindle, anterior surface of the iris, in the trabecular meshwork, on the lens and zonule and occasionally on the anterior hyaloid face. Even with deposition of pigment on zonular fibers, no zonular weakness, or zonular dehiscence has been reported in these cases. We report a unique case of PDS with bilateral spontaneous subluxation of crystalline lens. With characteristic findings of pigment distribution in both his eyes, the patient had concave iris configuration with heavily pigmented trabecular meshwork confirming the diagnosis of PDS. The patient had bilateral 180° temporal subluxation of crystalline lens in both his eyes. The usual cause of lens subluxation such as Marfan's Syndrome and Ehler's Danlos Syndrome was ruled out. The patient underwent right eye followed by left eye intracapsular cataract extraction with ab-interno technique with postoperative best-corrected visual acuity (BCVA) of 6/9 in both eyes. Spontaneous subluxation of crystalline lens in isolated PDS is not known to occur and has been reported by means of this case. We recommend a thorough assessment of zonular status in all cases of PDS.

Preliminary results from the comparison of simple limbal epithelial transplantation with conjunctival limbal autologous transplantation in severe unilateral chronic ocular burns.

PURPOSE: To compare the safety, efficacy, and clinical outcomes of simple limbal epithelial transplantation (SLET) with conjunctival-limbal autologous transplantation (CLAU) in severe unilateral ocular chemical burns. MATERIALS AND METHODS: Twenty patients of unilateral chronic ocular burns with more than 270° limbal stem cell deficiency and a healthy fellow eye were divided into two groups - ten patients of Group A underwent SLET while ten patients of Group B were operated for CLAU. Patients were followed up for 6 months and assessed for a stable epithelialized ocular surface, extent of reduction in vascularization and forniceal reconstruction, improvement in corneal clarity and visual acuity. RESULTS: A stable epithelialized corneal surface was obtained in all patients, with a significant reduction in the mean clock hours of vascularization in both the groups (P < 0.001). The mean symblepharon score showed a statistically significant reduction from 1.80 ± 1.14 to 0.30 ± 0.63 in Group A and 1.70 ± 1.06 to 0.15 ± 0.24 in Group B at 6 months. Corneal clarity, as well as best-corrected visual acuity, showed a statistically significant improvement in both the groups. CONCLUSION: Both the procedures, SLET and CLAU, were equally effective in achieving a stable ocular surface, forniceal reconstruction, and regression of corneal vascularization. The requirement of minimal donor tissue in SLET makes it a preferred option over CLAU in cases of uniocular chronic ocular burns.

Refractive outcome of wavefront guided laser in situ keratomileusis and wavefront guided photorefractive keratectomy in high pre-existing higher order aberration.

PURPOSE: To compare visual outcome and higher order aberrations (HOA) between wavefront-guided LASIK (WF-LASIK) and wavefront guided PRK (WF-PRK) in patients with high preoperative HOA. METHODS: Randomized prospective interventional study. Conducted at Guru Nanak Eye Centre, Maulana Azad Medical College, Delhi, India. Eighty myopic eyes of forty patients were included. INCLUSION CRITERIA: age more than 21 years, best corrected visual acuity of 20/20 or better, a stable refraction, to be off soft contact lens for minimum 14 days prior to preoperative examination, preoperative RMS HOA more than 0.35 µ, preoperative central corneal thickness at least 500 µm, estimated residual stromal bed thickness of at least 275 µm in patients undergoing WF-LASIK and 350 µm in patients undergoing WF-PRK. Exclusion criteria were severe dry eye, blepharitis, corneal disease and warpage, uveitis, posterior segment abnormalities involving the macula or optic nerve and systemic diseases. Patients were randomly divided into two groups. They underwent either WF-LASIK (group A) or WF-PRK (group B) over 2 years (40 eyes each). Patients were followed up for 6 months. Main outcome measures were efficacy, safety, stability, predictability and HOA. RESULTS: At 6 months mean uncorrected visual acuity (logMAR) in group A was -0.01 ± 0.04 and group B was 0.00 ± 0.07 (P = 0.23). HOA RMS (6mm pupil) in group A was 0.61 ± 0.24 µm and group B was 0.55 ± 0.25 µm. The increase was statistically significant in both the groups (P < 0.05). Both the groups showed similar efficacy, predictability and safety. CONCLUSION: WF-LASIK and WF-PRK have similar efficacy, safety and predictability, though WF-PRK induces less HOA.

Evaluation of visual functions in patients on ethambutol therapy for tuberculosis: a prospective study.

UNLABELLED: To study the incidence of clinical and subclinical optic nerve toxicity with ethambutol therapy in patients with tuberculosis and to evaluate the reversibility of its side effects after cessation of therapy. This prospective randomized controlled study included 60 newly diagnosed adult cases of tuberculosis, who were randomly assigned into two groups. The study group included 30 patients (60eyes) who received ethambutol as a part of their anti-tubercular treatment and the control group included 30 patients (60eyes) who did not receive ethambutol. The patients were examined on monthly basis. The visual parameters studied were best corrected visual acuity, pupillary reactions, optic disc changes, color vision, contrast sensitivity, pupil cycle time, visual field charting and visual evoked potential. Ethambutol was stopped in those patients in whom toxicity was detected and they were followed more frequently. Only one patient (3.3%) showed decrease in visual acuity, three patients (10%) developed visual field defects, two patients (6.7%) showed deterioration of contrast sensitivity, the pupil cycle time was prolonged in one eye and two patients (6.7%) showed abnormal visual evoked potential. During the therapy, all patients in the study group had normal pupillary reactions, fundus picture and color vision. CONCLUSIONS: Ethambutol induced ocular toxicity was seen in three patients (10%) in our study. The maximum visual recovery occurred in first six to eight weeks after stopping ethambutol. The visual recovery was complete in only one patient, but it was partial in two patients i.e. visual fields, contrast sensitivity and visual evoked potential remained abnormal.

Congenital accessory palpebral aperture--an addition to the spectrum of Delleman syndrome.

Delleman syndrome (oculocerebrocutaneous syndrome, MIM 164180) is characterized by orbital cysts, microphthalmia/anophthalmia, focal skin defects, skin appendages and multiple cerebral malformations. We herein describe a case of an 8-month-old male child with features suggestive of Delleman syndrome along with a rare congenital lid anomaly - an accessory palpebral aperture, not reported so far to the best of our knowledge.