Accelerated hydroxychloroquine toxic retinopathy.

PURPOSE: To report a case series of patients with retinal toxicity due to hydroxychloroquine (HCQ) within a short span of treatment. METHODS: A retrospective review of case records of patients with accelerated HCQ toxicity within 1 year of starting the treatment was done. Systemic co-morbidities, details of HCQ treatment, details of ocular examination, and results of multimodal investigations were noted. RESULTS: Nine patients (1 male, 8 females) with age ranging from 40 to 73 years (mean 54.2 ± 13.4 years) who showed accelerated HCQ toxicity were included. None had systemic conditions or drug history predisposing to early HCQ toxicity. The treatment duration ranged from 2 to 11 months and the cumulative HCQ dose ranged from 18 to 120 g (mean 45.0 ± 33.0 g). The visual acuity was normal in 8 (88.9%) patients and retinal evaluation was normal in 4 (44.4%). Optical coherence tomography was abnormal in 4 (44.4%). Six (66.6%) cases had reduced sensitivity in the parafoveal point on visual field testing. All 9 cases had multifocal electroretinographic changes diagnostic of HCQ toxicity. The HCQ treatment was stopped in 8 and continued with reduced dose in 1 patient. The mean duration of follow-up was 11.2 ± 9.6 months during which 5 patients showed improved mfERG and 1 patient had a stable mfERG. Visual fields improvement was noted in 2 cases. CONCLUSIONS: Patients on HCQ need to be kept on regular monitoring with more frequent follow-ups to detect signs of early onset toxicity and prevent permanent visual impairment. mfERG is an important diagnostic tool for HCQ toxicity.

Myopia and glaucoma progression among patients with juvenile onset open angle glaucoma: A retrospective follow up study.

OBJECTIVE: To identify the risk factors for glaucoma progression, especially the association with myopia, among treated juvenile open angle glaucoma (JOAG) patients. METHODS: Glaucomatous progression was analysed in the eyes of JOAG patients with at least 5-years of follow up in this retrospective study. Baseline variables such as age, inheritance pattern, baseline intraocular pressure (IOP), baseline central corneal thickness, visual acuity, baseline refractive error, spherical equivalent (SE) and duration of follow-up were noted. Stereoparametric global trend analysis and Moorfields Regression Analysis on confocal scanning laser ophthalmoscopy were used to detect progression. Variables associated with glaucoma progression, with respect to progressors (PG) and non-progressors (NPG) were analysed. Since both eyes of a patient were taken for analysis, a generalised estimating equation method was used to correct the bias. RESULTS: Among 74 eyes (37 subjects), glaucoma progression was noted in 11 eyes (14.9%) of 8 patients, with a median time to progression of 7.4 years (range 5-15.5 years). For myopes (SE ≤ -1.00 D), glaucoma progression was 18 times more likely than mild and no myopes (>-1DS) (p = 0.03, 95% CI: 1.14, 217.44). The prevalence of myopia in the JOAG, PG and NPG cohorts was 70.3%, 87.5%, and 65.5%, respectively. Myopia progression was noted at follow up in 70% patients. One-unit increase in baseline vertical cup disc ratio, 1 mmHg increase in IOP fluctuations and 1 dB year-1 depression of visual field were associated with 0.44, 0.06 and 0.07 D year-1 increases in the rate of myopia progression, respectively. CONCLUSIONS: JOAG progressors had a greater baseline myopic refraction and a faster myopia development over time. The development of myopia in JOAG eyes could be an indicator of glaucoma progression, and hence progressing myopic (≤-1 D) JOAG patients should be followed up more rigorously.

Extensive Chorio-retinal Damage Due to Dirofilaria Repens- Report of a Case.

Purpose: To report a case of ocular dirofilariasis causing extensive chorio-retinal damage.Method: Surgical removal of the worm and identification of the same by microscopic examinationand polymerase chain reaction.Results: The worm was identified as Dirofilaria repens.Conclusion: Ocular dirofilariasis is an arthropod borne parasitic infestation affecting the subconjunctival tissue and anterior chamber. Vitreous involvement in Dirofilaria is very rare. Dirofilaria repens can cause extensive chorio-retinal damage resembling diffuse unilateralsubacute neuroretinitis.

Further evidence of the association of latent Mycobacterium tuberculosis in Eales' disease.

PURPOSE: To find out association of Eales' disease with Mycobacterium tuberculosis. METHODS: A retrospective study was done recruiting patients visiting the uvea clinic with diagnosis of Eales' disease from 2015-2019. Seventy-nine eyes of 50 patients diagnosed as Eales' disease underwent Mantoux test, QuantiFERON-TB Gold test, high resolution computed tomography (HRCT) of the chest and anterior chamber or vitreous tap for TB genome polymerase chain reaction(PCR). RESULTS: The study included 41 males and 9 females. The mean age of the patient was 35.62 ± 11.49 y. Out of 50 patients, 42% (n = 21) patients had unilateral involvement. Mantoux test was positive in 73% patients. QuantiFERON-TB Gold test was positive in 56% patients. HRCT chest was suggestive of pulmonary tuberculosis in 34% patients. Out of 6 patients, PCR from anterior chamber tap showed TB genome positive in 2 (33.3%) patients. Out of 9 patients, vitreous tap PCR was positive for TB genome in 2 (22.2%) patients. CONCLUSIONS: Our study showed that one or more tests were positive for TB in Eales' disease suggesting a pivotal role of TB as a primary etiology for this disease. We conclude that Eales' disease is associated with Mycobacterium tuberculosis infection.

Macular telangiectasia type II with pachychoroid spectrum of macular disorders.

PURPOSE:: To report the cases with features of macular telangiectasia type II and pachychoroid spectrum of macular disorders simultaneously. METHODS:: It is a retrospective case series from a tertiary eye care center. Multimodal imaging features of these eyes including color fundus photographs, red free imaging, short-wave autofluorescence, fundus fluorescein angiography, indocyanine green angiography, and optical coherence tomography were studied. RESULTS:: Six eyes of three patients having combination of macular telangiectasia type II and pachychoroid group of disorders were found. Three eyes showed features of central serous chorioretinopathy, one eye had polypoidal choroidal vasculopathy, one eye had pachychoroid pigment epitheliopathy and one had thickened choroid. CONCLUSION:: This is the first report of macular telangiectasia type II in association with the pachychoroid spectrum of macular disorders and provides insight into possible common etiopathogenetic mechanisms.

Parapapillary Optic Nerve Head Drusen in Leber Congenital Amaurosis.

A 20-year-old male who was known to have Leber congenital amaurosis was assessed. Best-corrected visual acuity was counting fingers in both eyes (OU). Anterior segment OU revealed poorly reacting pupils and nystagmoid movements. Dilated fundus examination revealed widespread bone spicule pigmentation with "macular coloboma" OU (Figure a and b). Short-wave autofluorescence showed hyperautofluorescent buried optic nerve head drusen and generalized hypoautofluorescence OU (Figure c and d). Additionally, the left eye showed parapapillary drusen resulting from calcification of swollen and disrupted axons at a remote location in the parapapillary area (blue arrows; Figure b and d). The presence of buried optic nerve head drusen OU gives a clue to the diagnosis of parapapillary drusen, which can be easily mistaken for retinal astrocytoma. [Ophthalmic Surg Lasers Imaging Retina. 2018;49:554.].

Intravitreal bevacizumab for postviral fever retinitis: a novel approach for early resolution of macular oedema.

Severe macular oedema causing marked loss of vision is seen in cases of retinitis developing postviral fever. The use of antivascular endothelial growth factor agents for macular oedema and submacular fluid secondary to viral retinitis has not been studied or well established in the past. We report a case series of two patients of postviral retinitis with severe macular oedema resistant to steroid therapy, treated with intravitreal bevacizumab. The patients showed significant symptomatic improvement in the visual acuity. The retinitis lesions resolved slowly and macular oedema regressed. Bevacizumab appears to be a safe and useful agent to manage macular oedema subsequent to postviral retinitis. An early resolution of macular oedema helps in the preservation of visual acuity which left untreated can cause severe visual loss.

T(p-e)/QT ratio as an index of arrhythmogenesis.

An increasing number of basic and clinical studies have suggested that the interval from the peak to the end of the electrocardiographic T wave (T(p-e)) may correspond to the transmural dispersion of repolarization and that amplification of the T(p-e) interval is associated with malignant ventricular arrhythmias. In this review, we outline the utility of the T(p-e) interval and the T(p-e)/QT ratio as an electrocardiographic index of arrhythmogenesis for both congenital and acquired ion channel disease leading to ventricular arrhythmias. In healthy individuals, the T(p-e)/QT ratio has a mean value of approximately 0.21 in the precordial leads and it remains relatively constant between the heart rates from 60 to 100 beats per minute. Interestingly, the T(p-e)/QT ratio is significantly greater in the patients at risk for arrhythmic event such as those with long QT syndrome, Brugada syndrome, short QT syndrome, and also in patients with organic heart disease such as acute myocardial infarction. Functional reentry is the underlying mechanism for arrhythmogenesis associated with an increased T(p-e)/QT ratio.

L-type calcium current recovery versus ventricular repolarization: preserved membrane-stabilizing mechanism for different QT intervals across species.

BACKGROUND: Long QT syndrome is associated with early after-depolarization (EAD) that may result in torsade de pointes (TdP). Interestingly, the corrected QT interval seems to be proportional to body mass across species under physiologic conditions. OBJECTIVE: The purpose of this study was to test whether recovery of L-type calcium current (I(Ca,L)), the primary charge carrier for EADs, from its inactivated state matches ventricular repolarization time and whether impairment of this relationship leads to development of EAD and TdP. METHODS: Transmembrane action potentials from the epicardium, endocardium, or subendocardium were recorded simultaneously with a transmural ECG in arterially perfused left ventricular wedges isolated from cow, dog, rabbit, and guinea pig hearts. I(Ca,L) recovery was examined using action potential stimulation in isolated left ventricular myocytes. RESULTS: The ventricular repolarization time (action potential duration at 90% repolarization [APD(90)]), ranging from 194.7 +/- 1.8 ms in guinea pig to 370.2 +/- 9.9 ms in cows, was linearly related to the thickness of the left ventricular wall among the species studied. The time constants (tau) of I(Ca,L) recovery were proportional to APD(90), making the ratios of tau to APD(90) fall into a relatively narrow range among these species despite markedly different ventricular repolarization time. Drugs with risk for TdP in humans were shown to impair this intrinsic balance by either prolongation of the repolarization time and/or acceleration of I(Ca,L) recovery, leading to the appearance of EADs capable of initiating TdP. CONCLUSION: An adequate balance between I(Ca,L) recovery and ventricular repolarization serves as a "physiologic stabilizer" of ventricular action potentials in repolarization phases.