Nitin S Shetty

Ultrasound biomicroscopy of sclerotomy sites after pars plana vitrectomy for diabetic vitreous hemorrhage.

OBJECTIVE This study was aimed at assessing changes at the sclerotomy site using the ultrasound biomicroscope (UBM) in eyes that underwent primary pars plana vitrectomy for complications of proliferative diabetic retinopathy. DESIGN Prospective, observational case series. PARTICIPANTS Eighty-six eyes of 84 patients with vitreous hemorrhage caused by proliferative diabetic retinopathy. INTERVENTION Three-port pars plana vitrectomy followed by UBM evaluation of all sclerotomy sites between 6 and 8 weeks after surgery. Correlation with intraoperative findings done in case of reoperations. Forty-one eyes had repeat UBM at 6 months. MAIN OUTCOME MEASURES The changes at the sclerotomy site were classified into six groups: well healed, gape, plaque, vitreous incarceration, fibrovascular proliferation, and anterior hyaloidal fibrovascular proliferation (AHFVP). The UBM characteristics of each of the groups were defined. The findings at 6 months were compared with those at 6 to 8 weeks. RESULTS At 6 to 8 weeks after surgery, most sclerotomies were well healed or had either moderate to high reflective plaques bridging the site. Wound gape was seen in 22.1% of active ports, 32.6% of light ports, and 25.6% of infusion ports. Vitreous incarceration was seen most often at the infusion port (18. 6% of eyes). Fibrovascular proliferation was seen in 9.3% of active ports, 12.8% of light ports, and 15.1% of infusion ports. Thirteen eyes had recurrent vitreous hemorrhage 6 to 8 weeks after surgery. Cases with rebleeding and no fibrovascular proliferation at the sclerotomy on UBM did well with outpatient fluid-air exchange (two eyes) or observation only (three eyes). Those with fibrovascular proliferation on UBM (eight eyes) required more extensive surgery. CONCLUSIONS UBM is helpful in detecting complications at the sclerotomy sites after pars plana vitrectomy and is an invaluable tool in the assessment of the patient before reoperation.

Intraocular cysticercosis: clinical characteristics and visual outcome after vitreoretinal surgery

PURPOSE To report the clinical characteristics of, discuss the surgical options for, and analyze the factors affecting the anatomic and visual outcome of intraocular cysticercosis. DESIGN Retrospective, noncomparative, interventional case series. PARTICIPANTS Forty-five eyes of 44 Indian patients with posterior segment intraocular cysticercosis. METHODS The charts of 45 eyes, in which intraocular cysticercosis was removed by vitreoretinal surgery (either transscleral or transvitreal), were reviewed. MAIN OUTCOME MEASURES These included the postoperative retinal status and the best-corrected Snellen visual acuity. RESULTS Intraocular cysticercosis was present in the vitreous cavity of 27 eyes (60%) and in the subretinal space of 18 eyes (40%). Anterior segment inflammation was seen in 13 eyes (28.8%) and vitreous inflammation in 38 eyes (84.4%). Retinal detachment was observed in 22 eyes (48.8%), with proliferative vitreoretinopathy in 13 eyes (59.09%). Subretinal cysts anterior to the equator (4 eyes) were removed transsclerally, whereas subretinal cysts posterior to the equator and intravitreal cysts (41 eyes) were removed transvitreally. The mean follow-up was 10.5 months. At the last follow-up, the retina was attached in 39 eyes (86.6%); visual acuity of >/=5/200 was achieved in 67.5%. CONCLUSIONS Current vitreoretinal surgical techniques enable removal of intraocular cysticercosis in all cases, with reattachment of the retina in 86.6% and recovery of ambulatory vision in approximately 67% of cases.

Retinal detachment in Marfan syndrome: clinical characteristics and surgical outcome.

Purpose To describe the clinical characteristics of retinal detachments in patients with Marfan syndrome and report the surgical outcome of vitreoretinal surgery. Methods Records relating to 53 eyes of 45 patients with Marfan syndrome who underwent surgery for rhegmatogenous retinal detachment were reviewed. Of the 53 eyes, 24 (45.3%) underwent scleral buckling as the first procedure and 29 (54.7%) underwent vitrectomy surgery with scleral buckle as the first procedure. Main outcome measures included clinical characteristics of retinal detachment, reattachment rates, and functional improvement in vision. Results Characteristic findings included total retinal detachment in 40 (75.5%) eyes, atrophic holes in 24 (45.3%) eyes, more than four retinal breaks in 21 eyes (39.6%), preequatorial and postequatorial breaks in 20 (37.7%) eyes, giant retinal tears in six (11.3%) eyes, and proliferative vitreoretinopathy (posterior, anterior, or both) in nine (17%) eyes. In 30 (56.6%) eyes, retinal breaks were located only in the temporal half of the retina. Of the 24 eyes with myopia, 13 (54.2%) had a myopic correction greater than 7 diopters. At the median follow-up of 10.7 months, complete retinal reattachment was obtained in 87.6% and 86.2% of patients undergoing scleral buckling (including additional procedures such as vitrectomy) and vitrectomy surgery, respectively. In eyes with reattached retinas, a final visual acuity of 20/200 or better was obtained in 81% of the patients after scleral buckling and in 56% of the patients after vitrectomy surgery (P = 0.07). Conclusions Retinal detachment in Marfan syndrome is complete in 75% of the eyes. More than half (56%) the eyes had a retinal break only in the temporal half of the retina, and 83% had at least a break in the temporal half of the retina. Currently available vitreoretinal surgical techniques result in successful reattachment of the retina in approximately 86% of the eyes.

Subretinal fibrosis and nonrhegmatogenous retinal detachment associated with multifocal central serous chorioretinopathy.

Purpose: To report the rare occurrence of subretinal fibrosis in patients with multifocal central serous chorioretinopathy and evaluate the role of systemic corticosteroids and the effects of laser photocoagulation on multifocal leaks. Methods: A total of 29 patients (mean age, 37.7 years; 89.7% male) treated for subretinal fibrosis and multifocal central serous chorioretinopathy from 1983–1995 were reviewed retrospectively. Mean follow up was 26 months (range, 6.8–81 months). Results: Retinal detachment involved the macula in 72.4% cases. Fluorescein angiography showed a mean of 6.7 (range, 2–22) central serous chorioretinopathy leaks and a mean of 1.8 (range, 1–5) retinal pigment epithelial detachments. The fundus pictures of 23 patients who were taking systemic corticosteroids showed no improvement. Following laser treatment, however, retinal reattachment was obtained in all eyes, and improvement in visual acuity of > 2 Snellen lines was noted in 68.9% of patients. Conclusions: The presence of subretinal fibrosis with secondary retinal detachment in otherwise healthy young patients, particularly in men, should alert the physician to look for multifocal central serous retinopathy leaks. Systemic cortiosteroids did not prove effective in treating these patients, although laser treatment is recommended for each leak identified on an angiogram.

A Multivariate Analysis of Anatomic Success of Recurrent Retinal Detachment Treated with Pneumatic Retinopexy

PURPOSE The purpose of the study is to determine the success rate of pneumatic retinopexy (PR) after failed scleral buckling and to elucidate the predictors for anatomic failure by multiple logistic regression analysis. METHODS Thirty-six eyes with recurrent retinal detachment after failed scleral buckling underwent PR. Intraocular tamponade was attained with SF6 (20 eyes), C3F8 (13 eyes), and air (3 eyes). Median follow-up was 14 months. RESULTS Retinal reattachment was obtained in 69.4%. Multivariate analysis identified two risk factors for failure: location of retinal break either on the posterior slope or posterior to buckle (P = 0.01) and extent of retinal detachment greater than two quadrants (P = 0.02). CONCLUSIONS Pneumatic retinopexy is an effective alternative to revision surgical operations if the leaking retinal break is located on the buckle.

Results of vitrectomy in Terson syndrome.

BACKGROUND To report visual results of vitrectomy in Terson syndrome MATERIALS AND METHODS In 11 patients, 15 eyes underwent vitreous surgery for Terson syndrome. The mean follow up was 18.3 months. RESULTS An incomplete posterior vitreous separation was noted in 10 eyes (66.7%). An epiretinal membrane was present in 4 eyes (26.7%), and in 3 eyes, a retinal fold along the arcade was noticed. Significant visual improvement occurred in all eyes; visual acuity of 20/40 or better was achieved in 14 eyes (93.3%). Only 3 eyes developed lens opacity after surgery. CONCLUSION Vitrectomy in Terson syndrome provides excellent visual recovery. The complication rate, including the development of cataract, is low.

RPE65 gene: multiplex PCR and mutation screening in patients from India with retinal degenerative diseases

We used multiplex PCR followed by sequencing to screen for mutations in the 14 exons of theRPE65 gene in early-hildhood-onset autosomal recessive retinitis pigmentosa (arRP) and Leber’s congenital amaurosis (LCA) patients. The RPE65 protein is believed to play an important role in the metabolism of vitamin A in the visual cycle and mutations identified in the gene could have implications for vitamin A-based therapeutic intervention. We were able to identify a homozygous mutation (AAT → AAG) in exon 9 in an arRP patient and a heterozygous missense transversion (AAT → AAG) also in exon 9 of an LCA patient. We also identified a polymorphism in exon 10 (GAG → GAA) in an arRP as well as an LCA patient. Mutation screening would be greatly facilitated by multiplex PCR which could cut down costs, labour and time involved. The nucleotide changes observed in this study could bede novo. Though a larger study has been undertaken, from the preliminary results it appears that in India theRPE65 gene seems to be less involved in causation of LCA.

Scleral buckling: implant versus explant.

Purpose To compare the implant and explant techniques of scleral buckling. Methods This prospective, randomized clinical study compared the two techniques of scleral buckling. Variables such as size and extent of the buckle, duration of the surgery, complications, and anatomical and visual outcome were studied. The height of the buckle as measured by ultrasonography was also studied. Results No significant difference was found between the two groups for total duration of the surgery, complications, anatomical results, visual outcome, and buckle height. For the 1- to 2-quadrant buckles, duration of the surgery up to initiation of subretinal fluid drainage was found to be significantly shorter for the explant group. Serial ultrasonography showed significant reduction in buckle height over 6 months in both groups to an equal degree. Conclusions Scleral buckling seems to be equally effective whether performed as an implant or explant.

Indocyanine green dye-enhanced transpupillary thermotherapy of classic subfoveal choroidal neovascularization.

BACKGROUND AND OBJECTIVE To evaluate the efficacy of indocyanine green dye-enhanced transpupillary thermotherapy for the treatment of classic subfoveal choroidal neovascular membrane (CNVM) with differing etiologies. PATIENTS AND METHODS Nine eyes of 9 patients with classic subfoveal CNVM with different etiologies that was treated with indocyanine green dye-enhanced transpupillary thermotherapy were prospectively studied. All patients underwent pretreatment fluorescein angiography. Three minutes after dye injection (25 mg of indocyanine green), transpupillary thermotherapy was delivered using a modified diode laser at 810 nm, with a variable spot size of 0.8 to 2 mm depending on the size of the CNVM. A power range between 100 and 800 mW was used and treatment was initiated in one spot for 60 seconds; the end point was a barely detectable light gray appearance of the lesion. The outcome measures were assessed by Snellen visual acuity chart and obliteration of the CNVM by fluorescein angiography. Mean follow-up was 16 months. RESULTS Obliteration of the CNVM was seen in all patients during the last visit. Visual acuity improved in one eye and remained stable (+/-2 line change on Snellen chart) in three eyes. Three eyes revealed a moderate visual loss of 3 to 4 lines and two eyes had a severe decline (> 5 lines) in vision. None of the eyes exhibited recurrence of the CNVM during follow-up. CONCLUSIONS Indocyanine green dye-enhanced transpupillary thermotherapy was highly effective in closing classic CNVM in all cases without any recurrence. Visual acuity was either stabilized or improved in 4 of 9 eyes (44.5%).