Retinopathy of Prematurity-assist: Novel Software for Detecting Plus Disease

PURPOSE: To design software with a novel algorithm, which analyzes the tortuosity and vascular dilatation in fundal images of retinopathy of prematurity (ROP) patients with an acceptable accuracy for detecting plus disease. METHODS: Eighty-seven well-focused fundal images taken with RetCam were classified to three groups of plus, non-plus, and pre-plus by agreement between three ROP experts. Automated algorithms in this study were designed based on two methods: the curvature measure and distance transform for assessment of tortuosity and vascular dilatation, respectively as two major parameters of plus disease detection. RESULTS: Thirty-eight plus, 12 pre-plus, and 37 non-plus images, which were classified by three experts, were tested by an automated algorithm and software evaluated the correct grouping of images in comparison to expert voting with three different classifiers, k-nearest neighbor, support vector machine and multilayer perceptron network. The plus, pre-plus, and non-plus images were analyzed with 72.3%, 83.7%, and 84.4% accuracy, respectively. CONCLUSIONS: The new automated algorithm used in this pilot scheme for diagnosis and screening of patients with plus ROP has acceptable accuracy. With more improvements, it may become particularly useful, especially in centers without a skilled person in the ROP field.

Characteristics and surgical outcomes of rhegmatogenous retinal detachment following myopic LASIK

To describe the clinical features and surgical outcomes of rhegmatogenous retinal detachment [RRD] following myopic laser in situ keratomileusis [LASIK]. In a retrospective, non-comparative case series, 46 eyes that had undergone vitreoretinal surgery for management of RRD following myopic LASIK were identified. Data was reviewed with emphasis on characteristics of the RRD, employed surgical techniques, and anatomic and visual outcomes. Mean pre-LASIK myopia was -9.7 +/- 3.9 [range -4.00 to -18.00] diopters [D]. Mean interval between LASIK and development of RRD was 11.6 +/- 11.2 months. Posterior vitreous detachment was present in 44 eyes [95.6%]. The retinal breaks included flap tears in 36 [78.3%] eyes, giant tears in 8 [17.4%] eyes and atrophic holes in 2 [4.3%] eyes. In eyes with flap tears, the breaks were multiple, large or posterior to the equator in 24 [66.7%] eyes. Retinal breaks were related to lattice degeneration in 20 [43.5%] eyes of which, three had history of prophylactic barrier laser photocoagulation. Scleral buckling was performed as the initial procedure in 32 [69.6%] eyes and primary vitrectomy was undertaken in 14 [30.4%] eyes. The initial surgical procedure failed in 14 [30.4%] eyes due to proliferative vitreoretinopathy [PVR]. Retinal reattachment was finally achieved in 43 [93.4%] eyes. Postoperative visual acuity >/= 20/40 and >/= 20/200 was achieved in 16 [34.8%] and 25 [54.3%] eyes, respectively. Post-LASIK retinal detachment has a complex nature in eyes with moderate to high myopia. The retinal detachment is complex in terms of size, number and location of retinal breaks, is associated with a high rate of PVR and entails unfavorable visual outcomes

Surgical management in advanced stages of retinopathy of prematurity; our experience

Retinopathy of prematurity is a potentially blinding condition. In this article we describe the surgical management for advanced stages of the disease [stages 4 and 5]. Indications, options and alternative techniques are described through a review of articles and our personal experience

Hyperhomocysteinemia and central retinal vein occlusion in Iranian population

To evaluate total plasma homocysteine level during the acute phase of central retinal vein occlusion [CRVO] compared with a matched healthy group in Iranian population, and determine whether hyperhomocysteinemia is also a risk factor for CRVO. A study group contains 54 patients presenting with CRVO in recent one month, acute phase of the decease, was compared for fasting total plasma homocysteine level with a matched control group of 51 patients evaluated in the same clinic for a non retinal disease diagnosis. The mean total plasma homocysteine level was 14.76 +/- 7.67 micro mol/l in cases, and 11.42 +/- 3.74 micro mol/l in control subjects. It shows a significant difference [p=0.005] in mean plasma homocysteine level between the cases and control group. Odds ratio of CRVO for individuals with hyperhomocysteinemia was 2.88 [95% Cl=1.08-7.71 and p=0.03]. The overall multivanable-adjusted odds of CRVO in participants with plasma homocysteine level above 15 micro mol/l was 4.71 [95% Cl=1.46-15.19 and p=0.009] Hyperhomocysteinemia was not statistically different in each age group [<60 years: 27%. 61-70 years: 33.3%, 71-80 years: 31.6%, >81 years: 33.3%], Chi-square test, p=0.98]. Elevated total plasma homocysteine level is an independent risk factor for CRVO in Iranian population. In addition to an evaluation of all conventional cardiovascular risk factors, measurement of total homocysteine for evidence of hyperhomocysteinemia may be important in the initial investigation and management of patients with CRVO

Comparison of the effect of adjuvant 5-fluorouracil, low molecular weight heparin and daunomycin in combination with triamcinolone during vitrectomy in advanced retinal detachment

To compare the success rate of adjunctive 5-fluorouracil [5-FU] and low molecular weight heparin [LMWH], and daunomycin in combination with triamcinolone during vitrectomy in eyes with retinal detachment [RD] and proliferative vitreoretinopathy [PVR]. In this prospective randomized clinical trial, 69 eyes from 69 patients with RD and PVR [grade B or C] randomized to 3 groups. Group 1: received 5-FU and LMWH [200 microgram/ml 5-FU and 5 IU/ml LMWH, Fragmin]; group 2: received daunomycin [0.5 mg] in 500 cc infusion fluid; and group 3: control group. In all patients, 0.1 cc intravitreal triamcinolone was used during vitrectomy. The patients visited on day 1, week 1, month 1, 3 and 6. Best corrected visual acuity [BCVA] and retinal status compared in the 3 groups. Complete data were available for 60 out of 69 patients. Thirty five patients [58.3%] were male and 25 patients [41.7%] were female. The patient age range was 19-84 years and the mean age was 49. The groups did not have significant difference in age, sex, duration of detachment, severity of PVR, preoperative visual acuity [V/A], lens status, type of tamponade and encircling band and buckle. Postoperative V/A and retina status also was the same in the 3 groups. Perioperative infusion of 5-FU, LMWH and daunomycin does not significantly increase the success rate of patients with RD and PVR comparing to control group. Although visual acuity improvement and retina reattachment rate in group 1 and 2 were better than control group, but statistical analysis failed to show significant difference between the 3 groups

Retinopathy of prematurity: Single versus multiple-birth pregnancies

To compare the frequency and severity of retinopathy of prematurity [ROP] among singleton and multiple-birth neonates referred to Farabi Eye Hospital, Tehran-Iran. In this retrospective study, records of 99 consecutive neonates from multiplegestation pregnancies including 68 twins, 26 triplets and 5 quadruplets who were screened for ROP from 2002 to 2004 were reviewed. The frequency, severity and risk factors for ROP were determined and compared to a group of singletons who were matched in terms of gender, birth weight [BW], gestational age [GA], oxygen therapy, respiratory distress syndrome, blood transfusion, sepsis and phototherapy. ROP was present in 12.1% of multiple-birth neonates as compared to 15.1% of singletons [P=0.53]. Threshold ROP was present in 6.1% of multiple-birth neonates versus 7.1% of singletons [P=0.62]. ROP was detected in 60% of quadruplets versus 9.6% of twins and triplets; threshold disease was observed in 40% of quadruplets as compared to 4.2% of twins and triplets [P<0.03]. However, considering the effect of BW and GA, logistic regression analysis revealed no statistically significant difference in the frequency and severity of ROP among subgroups of multiple-gestation pregnancies. There was no significant difference between multiple-birth neonates and matched singletons in terms of frequency and severity of ROP. Any apparent higher rate may be due to independent risk factors such as low birth weight and gestational age rather than multiple pregnancies per se. Screening for ROP in multiple gestation births may be conducted according to standard protocols applied for singletons

Intravitreal bevacizumab versus combined bevacizumab and triamcinolone acetonide for neovascular age-related macular degeneration

To compare the short-term outcomes of intravitreal bevacizumab [IVB] with the combination of IVB and intravitreal triamcinolone acetonide [IVB/IVT] for treatment of neovascular age-related macular degeneration [AMD]. This randomized clinical trial was performed on 92 eyes of 90 patients with subfoveal and juxtafoveal choroidal neovascularization [CNV] secondary to AMD. The eyes were randomly assigned to receive IVB 1.25 mg alone [53 eyes] or in combination with IVT 2 mg [39 eyes]. Best-corrected visual acuity [BCVA] and fundus autofluorescence were assessed, and fluorescein angiography [FA] and optical coherence tomography [OCT] were performed at baseline and repeated 6 weeks after treatment. Mean age was 70.6 +/- 8.7 [range 50-89] years and 57.7% of the patients were male. BCVA improved from 1.03 +/- 0.40 to 0.93 +/- 0.38 logMAR [P=0.001] in the IVB group and from 1.08 +/- 0.33 to 0.91 +/- 0.38 logMAR [P=0.008] in the IVB/IVT group. There was a trend toward greater visual improvement with combined therapy [P=0.06]. BCVA improvement was greater in eyes with +1 versus those with +2 [P=0.049] and +3 [P < 0.001] fundus autofluorescence at baseline. Mean decrease in central macular thickness was 113 +/- 115 micro m [P < 0.001] in the IVB group versus 53.96 +/- 125 micro m [P=0.008] in the IVB/IVT group with no intergroup difference [P=0.38]. FA showed decreased leakage in 57.4%, increased leakage in 12.8% and no change in 29.8% of patients in the IVB group. Corresponding figures were 60.0%, 5.7% and 34.3% in the IVB/IVT group [P=0.556]. Addition of triamcinolone acetonide to bevacizumab for treatment of neovascular AMD does not seem to significantly increase its short-term efficacy. More severe fundus autofluorescence appears to be predictive of poorer response to treatment

Subtenon carboplatin in the management of intraocular retinoblastoma

To evaluate the efficacy of subtenon carboplatin as an adjuvant to systemic chemotherapy in the management of intraocular retinoblastoma. This study was conducted as a randomized, double-masked clinical trial. A diagnosis of intraocular retinoblastoma was made based on clinical examination, ultrasonography and orbital CT-scanning. The greatest basal dimension of the tumors was estimated in disc diameter [DD] by indirect ophthalmoscopy. Tumor thickness was determined by ultrasonography. Each eye was assigned to one of 10 blocks based on tumor stage [Reese-Ellseworth classification] and randomly received systemic chemotherapy alone [control group] or systemic chemotherapy plus 20mg subtenon carboplatin [case group]. Indirect laser photocoagulation or cryotherapy was performed as additional treatment. The study included 35 tumors in 17 eyes of 14 patients [19 tumors in 8 eyes of the control group and 16 tumors in 9 eyes of the case group]. There was 57.22% and 61.73% decrease in tumor thickness in the control and case groups, respectively [P=0.12]. The decrease in greatest basal tumor dimension in the control group [47.32%] was not significantly different from that in the case group [38.80%]. One eye [12.5%] in the control group and 3 eyes [33.3%] in the case group were enucleated. Adjuvant subtenon carboplatin does not seem to increase the efficacy of systemic chemotherapy in the treatment of intraocular retinoblastoma