Aim: To systematically refine and recommend parameter settings of spot size, power, and treatment duration using the Pascal^® photocoagulator, a multi-spot, semi-automated, short-duration laser system. Materials and Methods: A retrospective consecutive series with 752 Caucasian eyes and 1242 laser procedures over two years were grouped into, (1) 374 macular focal / grid photocoagulation (FP), (2), 666 panretinal photocoagulation (PRP), and (3) 202 barrage photocoagulation (BP). Parameters for power, duration, spot number, and spot size were recorded for every group. Results: Power parameters for all groups showed a non-gaussian distribution; FP group, median 190 mW, range 100 - 950 mW, and PRP group, median 800 mW, range 100 - 2000 mW. On subgroup comparison, for similar spot size, as treatment duration decreased, the power required increased, albeit in a much lesser proportion than that given by energy = power x time. Most frequently used patterns were single spot (89% of cases) in FP, 5 Χ 5 box (72%) in PRP, and 2 Χ 2 box (78%) in BP. Spot diameters as high as ≈ 700 μm on retina were given in the PRP group. Single session PRP was attempted in six eyes with a median spot count of 3500. Conclusion: Overall, due to the small duration of its pulse, the Pascal^® photocoagulator tends to use higher powers, although much lower cumulative energies, than those used in a conventional laser. The consequent lesser heat dissipation, especially lateral, can allow one to use relatively larger spot sizes and give more closely spaced burns, without incurring significant side effects.

Aim: To compare the effect of intravitreal bevacizumab and triamcinolone in patients with macular edema after central retinal vein occlusion (CRVO), presenting with poor visual acuity. Materials and Methods: It was a retrospective, comparative case series of 38 consecutive eyes, with macular edema secondary to CRVO, with 20/200 or worse vision, which were treated primarily either with intravitreal bevacizumab (1.25 mg; 24 eyes) or intravitreal triamcinolone (4 mg; 14 eyes). During follow-up, 3.6 ± 0.8 re-injections of bevacizumab and 2.4 ± 0.5 re-injections of triamcinolone were administered (P = 0.080). The main outcome measures were the best-corrected visual acuity and the central macular thickness by optical coherence tomography during 12 months of follow-up. Results: At 12 months, visual acuity (logMAR) was changed from 1.03 ± 0.39 (baseline) to 0.92 ± 0.39 (P = 0.374) and the central macular thickness was reduced from a baseline of 713.6 ± 179.3 μm to 310.8 ± 205.2 μm (P = 0.000). Neither the bevacizumab nor triamcinolone groups varied significantly in visual acuity and central macular thickness at 1, 3, 6, and 12 months after treatment. Neovascular glaucoma developed in two of the 14 eyes (14%) in the triamcinolone group. Conclusion: In patients with CRVO and poor vision, intravitreal bevacizumab and intravitreal triamcinolone were associated with a reduction in macular edema; however, neither treatment achieved significant visual acuity improvement by the 12-month follow-up.

Background: Infrared (IR) radiation is becoming more popular in industrial manufacturing processes and in many instruments used for diagnostic and therapeutic application to the human eye. Aim : The present study was designed to investigate the effect of IR radiation on rabbit's crystalline lens and lens membrane. Materials and Methods: Fifteen New Zealand rabbits were used in the present work. The rabbits were classified into three groups; one of them served as control. The other two groups were exposed to IR radiation for 5 or 10 minutes. Animals from these two irradiated groups were subdivided into two subgroups; one of them was decapitated directly after IR exposure, while the other subgroup was decapitated 1 hour post exposure. IR was delivered from a General Electric Lamp model 250R 50/10, placed 20 cm from the rabbit and aimed at each eye. The activity of Na ⁺ -K ⁺ ATPase was measured in the lens membrane. Soluble lens proteins were extracted and the following measurements were carried out: estimation of total soluble protein, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Fourier transform infrared (FTIR) spectroscopy. For comparison between multiple groups, analysis of variance was used with significance level set at P < 0.001. Results: The results indicated a change in the molecular weight of different lens crystalline accompanied with changes in protein backbone structure. These changes increased for the groups exposed to IR for 10 minutes. Moreover, the activity of Na ⁺ -K ⁺ ATPase significantly decreased for all groups. Conclusions: The protein of eye lens is very sensitive to IR radiation which is hazardous and may lead to cataract.

Visual field assessment is important in the evaluation of lesions involving the visual pathways and should be performed at baseline and periodically in the follow-up. Standard automated perimetry has been shown to be adequate in neuro-ophthalmic practise and is now the technique of choice for a majority of practitioners. Goldman kinetic visual fields are useful for patients with severe visual and neurologic deficits and patients with peripheral visual field defects. Visual fields are useful in monitoring progression or recurrence of disease and guide treatment for conditions such as idiopathic intracranial hypertension (IIH), optic neuropathy from multiple sclerosis, pituitary adenomas, and other sellar lesions. They are used as screening tools for toxic optic neuropathy from medications such as ethambutol and vigabatrin. Visual field defects can adversely affect activities of daily living such as personal hygiene, reading, and driving and should be taken into consideration when planning rehabilitation strategies. Visual field testing must be performed in all patients with lesions of the visual pathway.

Advancements in physics, computers, and imaging science in the last century have seen neuro-imaging evolving from a plain X-ray to computed tomography, magnetic resonance imaging scans, noninvasive angiography, and special sequences such as fat suppression, fluid attenuation recovery and diffusion-weighted imaging. A prompt prescription of an appropriate imaging modality and the most suitable sequence can increase the diagnostic yield, and in many instances, it can be a sight-saving and even a life-saving decision. This article discusses basic principles of neuro-imaging, its common indications, and the appropriate application in an ophthalmology practice.

Optic neuritis is an inflammatory condition of the optic nerve characterized by a sudden onset of unilateral visual loss, usually affecting young females. Demyelination associated with multiple sclerosis (MS) is the most common cause in regions where MS is prevalent; while in other places, there are a substantial proportion of cases where infective or autoimmune causes are seen. Optic Neuritis Treatment Trial (ONTT) was the first major study that provided information on the natural history, role of steroids in treatment and risk of development of MS. Subsequently, numerous clinical trials have evaluated different modalities of management of optic neuritis and MS. The Controlled High-Risk Subjects Avonex Multiple Sclerosis Prevention Study (CHAMPS); the Prevention of Relapses and Disability by Interferon β-1a Subcutaneously in Multiple Sclerosis (PRISMS) Trial; and, most recently, the Betaferon in Newly Emerging Multiple Sclerosis for Initial Treatment (BENEFIT) Study have provided large amount of information on the natural history of optic neuritis and management options available. However, due to the low prevalence of MS reported in Asian studies, high cost of therapy and indefinite time period of treatment, it may not be cost effective to start interferon therapy in most cases.

Ischemic optic neuropathies (IONs) consist primarily of two types: anterior ischemic optic neuropathy (AION) and posterior ischemic optic neuropathy (PION). AION comprises arteritic AION (A-AION: due to giant cell arteritis) and non-arteritic AION (NA-AION: due to other causes). PION consists of arteritic PION (A-PION: due to giant cell arteritis), non-arteritic PION (NA-PION: due to other causes), and surgical PION (a complication of several systemic surgical procedures). These five types of ION are distinct clinical entities etiologically, pathogenetically, clinically and from the management point of view. In the management of AION, the first crucial step with patients aged 50 and over is to identify immediately whether it is arteritic or not because A-AION is an ophthalmic emergency and requires urgent treatment with high-dose steroid therapy to prevent any further visual loss in one or both eyes. Patients with NA-AION, when treated with systemic corticosteroid therapy within first 2 weeks of onset, had significantly better visual outcome than untreated ones. Systemic risk factors, particularly nocturnal arterial hypotension, play major roles in the development of NA-AION; management of them is essential in its prevention and management. NA-PION patients, when treated with high-dose systemic steroid therapy during the very early stages of the disease, showed significant improvement in visual acuity and visual fields, compared to untreated eyes. A-PION, like A-AION, requires urgent treatment with high-dose steroid therapy to prevent any further visual loss in one or both eyes. There is no satisfactory treatment for surgical PION, except to take prophylactic measures to prevent its development.

Toxic optic neuropathy (TON) is a disease entity which is not only underdiagnosed, but also often diagnosed at a stage when recovery of vision is not possible. This article gives an overview of common causes, clinical features, and management of TON.

A pilot study was designed to evaluate the safety and efficacy of 23-gauge vitrectomy under topical anesthesia. Five eyes of five patients underwent 23-gauge sutureless vitrectomy under topical anesthesia with a pledget soaked in 0.5% proparacaine hydrochloride anesthetic, for vitreous hemorrhage (four eyes), epiretinal membrane (one eye). Subjective pain and discomfort were graded using a visual analogue chart from 0 (no pain or discomfort) to 4 (severe pain and discomfort). At the end of surgery no patch was applied and patients were given dark glasses. Patients underwent an immediate postoperative assessment, followed by next day and one week postoperative evaluation. Four patients had Grade 0 pain during the surgery. One patient had Grade 1 pain during the placement and withdrawal of the micro cannulas. The surgical outcomes were favorable. 23-gauge vitrectomy under topical anesthesia is safe and effective in selected cases. Further study is recommended to validate the outcome of this study.

A 28-year-old, healthy female, who had a recent repeated history of miscarriage, presented with bilateral choroidal neovascular membranes (CNVM), for which she received photodynamic therapy with three doses of lucentis, at intervals of one month each, to which she responded. After five months, the patient again presented with complaints of diminution of vision since 15 days. She had a history of miscarriage two days before presenting to our clinic. CNVM was scarred at this time and the fundus picture showed multiple small punctate spots around the fovea at the level of the choroid, which showed early hyperfluroscence on fundus fluorescein angiography, suggestive of punctate inner choroidopathy. She was advised systemic steroids, to which she responded dramatically.

Choroidal neovascularization (CNV) is a rare complication associated with coloboma of the choroid. We describe three cases of coloboma choroid where there was loss of vision due to CNV development at the edge of the coloboma. One was managed by photodynamic therapy alone and two were managed by a combination of reduced fluence PDT and intravitreal bevacizumab. Significantly we noted that one treatment session was sufficient to achieve regression of the CNV and improvement in visual acuity.

Wegener's granulomatosis (WG) is a multisystem vasculitic disorder which can commonly afflict various components of the eye. Here we describe some unusual ocular manifestations of the disease in one patient. A young male with history of upper respiratory tract symptoms including epistaxis, nasal stuffiness and maxillary sinus pain presented with bilateral lacrimal gland abscess and ptosis. Lacrimal gland biopsy revealed granulomatous vasculitis. Lung cavities, positive cytoplasmic-antineutrophil cytoplasmic antibodies and high titers of serine proteinase-3 antibodies confirmed the diagnosis of WG. The patient developed dry eyes after a month of first presentation. There was no dryness of mouth, suggesting the absence of salivary gland involvement, and antinuclear antibodies as well as antibodies against Ro and La antigens classical of primary Sjogren's syndrome were absent. Granulomatous vasculitis of lacrimal gland leading to abscess formation and dryness of eyes has not been described in WG and reflects the aggressive nature of inflammatory process in this disease.

We report a case of dilated episcleral vein with secondary open angle glaucoma. A 65-year-old female presented with redness of both the eyes without any prior systemic history. Her ocular examination revealed dilated episcleral veins and a high intraocular pressure (IOP) of 38 mm Hg in the right eye. Systemic examination was negative for carotid cavernous fistula, low-grade dural arteriovenous fistula, dysthyroid ophthalmopathy, and primary pulmonary hypertension. During follow-up, her IOP remained in high thirties despite maximum medications. She underwent right eye trabeculectomy with partial thickness sclerectomy with sclerotomy. In the beginning, the sclerotomy incision was not deepened into the suprachoroidal space. She developed choroidal effusion during surgery and the sclerotomy was deepened into suprachoroidal space and straw color fluid was drained. Postoperatively, she developed choroidal effusion, which resolved with conservative management. This case highlights the importance of sclerotomy in such cases of high episcleral venous pressure.

To compare structural and functional outcome and time efficiency between standard spot sized conventional pulsed mode diode laser and continuous mode large spot transpupillary thermotherapy (LS TTT) for treatment of high risk prethreshold retinopathy of prematurity (ROP). Ten eyes of five preterm babies having bilateral symmetrical high risk prethreshold ROP were included in this study. One eye of each baby was randomized to get either standard spot sized conventional pulsed mode diode laser or continuous mode LS TTT. There was no significant difference between structural or functional outcome in either group. The mean time taken for conventional diode laser was 20.07 minutes, while that for LS TTT was 12.3 minutes. LS TTT was 40% more time efficient than the conventional laser. It may be better suited for the very small fragile premature infants as it is quicker than the conventional laser.

Dye-assisted internal limiting membrane (ILM) peeling and gas tamponade is the surgery of choice for idiopathic macular holes. Indocyanine green and trypan blue have been extensively used to stain the ILM. However, the retinal toxicity of indocyanine green and non-uniform staining with trypan blue has necessitated development of newer vital dyes. Brilliant blue G has recently been introduced as one such dye with adequate ILM staining and no reported retinal toxicity. We performed a 23-gauge pars plana vitrectomy with brilliant blue G-assisted ILM peeling in six patients with idiopathic macular holes, to assess the staining characteristics and short-term adverse effects of this dye. Adequate staining assisted in the complete removal of ILM and closure of macular holes in all cases. There was no evidence of intraoperative or postoperative dye-related toxicity. Brilliant blue G appears to be safe dye for ILM staining in macular hole surgery.

We report a case that developed acute postoperative endophthalmitis after transconjunctival sutureless vitrectomy using the 23-gauge system. A 66-year-old man underwent non-sutured 23-gauge pars plana vitrectomy for epimacular membrane. Since the patient developed signs of acute endophthalmitis and decreased visual acuity to counting fingers on the second postoperative day, re-vitrectomy with silicone oil was performed. The patient responded well to re-vitrectomy, injection of silicone oil and intravitreal antibiotic injections. Methicillin resistant Staphylococcus epidermidis was cultured from vitreous samples. Silicone oil was extracted at 11 months. The patient remains stable at 14 months with a final visual acuity of 20/50.

Synergistic convergence is an ocular motor anomaly where on attempted abduction or on attempted horizontal gaze, both the eyes converge. It has been related to peripheral causes such as congenital fibrosis of extraocular muscles (CFEOM), congenital cranial dysinnervation syndrome, ocular misinnervation or rarely central causes like horizontal gaze palsy with progressive scoliosis, brain stem dysplasia. We hereby report the occurrence of synergistic convergence in two sisters. Both of them also had kyphoscoliosis. Magnetic resonance imaging (MRI) brain and spine in both the patients showed signs of brain stem dysplasia (split pons sign) differing in degree (younger sister had more marked changes).

We report a case of a bilateral posterior chamber implantable collamer lens (ICL) implantation post-clear lens extraction, to reduce the residual hyperopia, in a patient with nanophthalmic eyes. A 30-year-old female patient, keen to reduce her dependency on glasses and contact lenses, came to our refractive surgery department. Her refractive error was +12.0 and +12.5 diopters in the right and left eye, respectively, with steep corneas on keratometry and a shallow anterior chamber depth. She underwent clear lens extraction with implantation of +35.0 D and +40.0 D IOL in the right eye and left eye, respectively. Her post-operative best-corrected visual acuity was 20/30 with +8.5 D in the right eye and +6 D in the left. She underwent bilateral ICL implantation. Postoperatively after 6 months, her unaided visual acuity was 20/30 in both eyes. In conclusion, ICL implantation can be considered to correct residual hypermetropic ametropia in pseudophakic eyes when other options have limitations.