Zafer Cebeci

Human ocular filariasis: further evidence on the zoonotic role of Onchocerca lupi.

BackgroundAmong ocular vector-borne pathogens, Onchocerca volvulus, the agent of the so-called “river blindness”, affects about 37 million people globally. Other Onchocerca spp. have been sporadically reported as zoonotic agents. Cases of canine onchocerciasis caused by Onchocerca lupi are on the rise in the United States and Europe. Its zoonotic role has been suspected but only recently ascertained in a single case from Turkey. The present study provides further evidence on the occurrence of O. lupi infesting human eyes in two patients from Turkey (case 1) and Tunisia (case 2). The importance of obtaining a correct sample collection and preparation of nematodes infesting human eyes is highlighted.MethodsIn both cases the parasites were identified with morpho-anatomical characters at the gross examination, histological analysis and anatomical description and also molecularly in case 1.ResultsThe nematode from the first case was obviously O. lupi based on their morphology at the gross examination, histological analysis and anatomical description. In the second case, although the diagnostic cuticular characters were not completely developed, other features were congruent with the identification of O. lupi. Furthermore, the morphological identification was also molecularly confirmed in the Turkish case.ConclusionsThe results of this study suggest that O. lupi infestation is not an occasional finding but it should be considered in the differential diagnosis of other zoonotic helminths causing eye infestation in humans (e.g., D. immitis and Dirofilaria repens). Both cases came from areas where no cases of canine onchocerciasis were previously reported in the literature, suggesting that an in depth appraisal of the infestation in canine populations is necessary. Physicians and ophthalmologists are advised on how to preserve nematode samples recovered surgically, to allow a definitive, correct etiological diagnosis.

Peripapillary Retinoschisis in Glaucoma Patients

Purpose. To investigate peripapillary retinoschisis and its effect on retinal nerve fiber layer (RNFL) thickness measurements by using spectral-domain optical coherence tomography (SD-OCT) in glaucomatous eyes. Methods. Circumpapillary RNFL (cpRNFL) B-scan images of 940 glaucoma patients (Group 1) and 801 glaucoma-suspect patients (Group 2) obtained by SD-OCT were reviewed. The structural and clinical characteristics of the retinoschisis were investigated. The RNFL thickness measurements taken at the time of retinoschisis diagnosis and at the follow-up visits were also compared. Results. Twenty-nine retinoschisis areas were found in 26 of the 940 glaucoma patients (3.1%) in Group 1 and seven areas were found in 801 patients (0.87%) in Group 2. In glaucomatous eyes, the retinoschisis was attached to the optic disc and overlapped with the RNFL defect. At the time of retinoschisis, the RNFL thickness was statistically greater in the inferior temporal quadrant when compared with the follow-up scans (p < 0.001). No macular involvement or retinal detachment was observed. Conclusion. The present study investigated 33 peripapillary retinoschisis patients. Increase in RNFL thickness measurements was observed at the time of retinoschisis. It is important to examine the cpRNFL B-scan images of glaucoma patients so that the RNFL thickness is not overestimated.

Fulminant Ocular Toxoplasmosis: The Hazards of Corticosteroid Monotherapy

ABSTRACT Purpose: To describe fulminant toxoplasma retinochoroiditis induced by corticosteroid monotherapy. Methods: Clinical records of nine patients were reviewed. Results: All patients (five female, four male; aged 15–64 years) had been misdiagnosed as unilateral non-infectious uveitis and given systemic and/or local corticosteroid injections elsewhere. Mean disease duration before referral was 105.6 ± 71 (45–240) days. Visual acuity at presentation was <20/200 in six eyes. Average lesion size was 6.6 disc areas in eight eyes and all four quadrants were involved in one. Toxoplasma DNA was detected in eight tested eyes. Mean duration of anti-toxoplasmic therapy was 92.5 ± 37.1 days. Three eyes developed rhegmatogenous retinal detachment. Four patients underwent pars plana vitrectomy. Final visual acuity was <20/200 in five eyes. Conclusions: Iatrogenic immunosuppression due to initial misdiagnosis may lead to an aggressive course and serious complications of ocular toxoplasmosis, a potentially self-limiting infection.

Superselective intra-arterial chemotherapy in the primary management of advanced intra-ocular retinoblastoma: first 4-year experience from a single institution in Turkey

To report our 4‐year experience in Turkey, with advanced intra‐ocular retinoblastoma managed primarily with intra‐arterial chemotherapy (IAC).

Role of implants in the treatment of diabetic macular edema: focus on the dexamethasone intravitreal implant

Diabetic macular edema (DME) is the leading cause of sight-threatening complication in diabetic patients, and several treatment modalities have been developed and evaluated to treat this pathology. Intravitreal agents, such as anti-vascular endothelial growth factors (anti-VEGF) or corticosteroids, have become more popular in recent years and are widely used for treating DME. Sustained release drugs appear to be mentioned more often nowadays for extending the period of intravitreal activity, and corticosteroids play a key role in inhibiting the inflammatory process in DME. A potent corticosteroid, dexamethasone (Ozurdex®), in the form of an intravitreal implant, has been approved for various ocular etiologies among which DME is also one. This review evaluates the role of implants in the treatment of DME, mainly focusing on the dexamethasone intravitreal implant.

Excitability changes at brainstem and cortical levels in blind subjects.

OBJECTIVES This study was designed to search potential changes in trigemino-facial system in blind subjects by the use of relatively well-established electrophysiological methods. Excitability changes in the motor cortex were also investigated by transcranial magnetic stimulation studies (TMS) with the expectation of finding some abnormal interactions between the cortex and brainstem. METHODS Twenty blind (BS) and 13 control subjects (CoS) were included in the study. Blink reflex and its recovery with paired electrical stimulation were studied at 150, 200, 300, 400 and 500 ms interstimulus intervals (ISI). Facial F waves elicited by buccal branch stimulation were recorded from nasalis muscles. Motor cortex excitability with recordings from left first dorsal interosseus muscle was studied by using magnetically elicited silent periods and paired magnetic stimuli, subthreshold conditioning and suprathreshold test, given at ISIs of 2, 3, 4, 10, 12, 15 and 20 ms. RESULTS Blink reflex recovery was significantly reduced in BS group comparing to CoS at 400 and 500 ms ISIs. This difference between the groups was more prominent for the responses evoked by the initial stimulation side and faded away with stimulations on the contralateral side. Facial F wave amplitudes and F/M amplitude ratios were higher in BS group. In TMS studies, the early inhibitions at 2 and 4 ms were found to be significantly less in BS as compared to that of CoS. CONCLUSIONS The reduced blink reflex recovery and its fast restoration with continuing stimulation might be explained by conditioning and extinction processes which have been shown to be mainly carried out by cerebellar-brainstem pathways. Our TMS studies showed reduced intracortical inhibition in the motor cortices of BS cases and facial F wave studies revealed the possible effect of this altered excitability on the facial motor nuclei. SIGNIFICANCE Firing probabilities of facial motor neurons in BS are probably determined by the equilibrium between the low-set excitability of blink reflex interneurons and the enhanced excitability brought on by the descending motor pathways.

Corneal Collagen Cross-Linking in Pellucid Marginal Degeneration: 2 Patients, 4 Eyes.

Purpose. To report the long-term results of corneal collagen cross-linking (CXL) with riboflavin and ultraviolet-A irradiation in 4 eyes of 2 patients affected by pellucid marginal degeneration (PMD). Methods. This study involved the retrospective analysis of 4 eyes of 2 patients with PMD that underwent CXL treatment. Of the eyes, three had only CXL treatment and one had CXL treatment after an intrastromal corneal ring segment implantation. We have pre- and postoperatively evaluated uncorrected distance visual acuity (UDVA), best corrected distance visual acuity (BCDVA), corneal topography (Pentacam), specular microscopy, and pachymetry. Results. Patient 1 was a woman, aged 35, and Patient 2 was a man, aged 33. The right eye of Patient 1 showed an improvement in her BCDVA, from 16/40 to 18/20 in 15 months, and her left eye improved from 12/20 to 18/20 in 20 months. Patient 2s right eye showed an improvement in his BCDVA, from 18/20 to 20/20 in 43 months, and his left eye improved from 16/20 to 18/20 in 22 months. No complications were recorded during or after the treatment. Conclusion. CXL is a safe tool for the management of PMD, and it can help to stop the progression of this disease.

Dramatic regression of presumed acquired retinal astrocytoma with photodynamic therapy

Photodynamic therapy (PDT) has been used for treatment of various intraocular tumors including choroidal hemangioma, vasoproliferative tumor, amelanotic choroidal melanoma and choroidal neovascular membrane due to choroidal osteoma. This case report documents the effect of PDT for a presumed acquired retinal astrocytoma. A 42-year-old female with a juxtapapillary acquired astrocytoma was treated with a single session of PDT using standard parameters. The tumor showed dramatic regression over 6 months into a fibrotic scar. It remained regressed and stable with 20/20 vision after 51 months of follow-up. We believe that PDT can be used as a primary treatment for acquired retinal astrocytoma.

Atypical Central Serous Chorioretinopathy

Bullous central serous chorioretinopathy (CSCR) is a rare variant of CSCR characterized by severe serous retinal detachment which especially involves the inferior quadrants. Corticosteroid therapy administered for systemic or ocular misdiagnoses may induce and exacerbate CSCR. The purpose of this study was to report diagnosis and treatment results of an unusual case of bullous CSCR induced by systemic and periocular corticosteroid therapy received at another medical center due to a misdiagnosis of Vogt-Koyanagi-Harada disease.

Clinical Features and Course of Patients with Peripheral Exudative Hemorrhagic Chorioretinopathy

Objectives: To evaluate the clinical characteristics of patients who were followed in our clinic with the diagnosis of peripheral exudative hemorrhagic chorioretinopathy (PEHC). Materials and Methods: Medical records of 12 patients who were diagnosed with PEHC in İstanbul University İstanbul Faculty of Medicine, Department of Ophthalmology between July 2006 and June 2014 were reviewed retrospectively. Results: This study included 21 eyes of 12 patients. Four (33.3%) of the patients were male and 8 (66.7%) were female and ages ranged between 73 and 89 years. Eight (66.7%) of the patients were referred to us with the diagnosis of choroidal mass. Unilateral involvement was found in 3 and bilateral involvement in 9 patients. Temporal quadrants were involved in all eyes. Fifteen eyes (71.4%) had subretinal hemorrhage and hemorrhagic/serous retinal pigment epithelial detachment, 11 (52.4%) had lipid exudation, 5 (23.8%) had chronic retinal pigment epithelium alterations, 2 (9.5%) had subretinal fibrosis and 1 (4.8%) had vitreous hemorrhage. PEHC lesions were accompanied by drusen in 11 eyes (52.4%), geographic atrophy in 2 eyes (9.5%), and choroidal neovascularization scar in 2 eyes (9.5%). Treatment was done in both eyes of a patient for lesions which threatened the macula, in a patient with bilateral macular edema and in a patient with vitreous hemorrhage. The remaining eyes were followed-up without any treatment because the lesions did not threaten the macula and they showed no progression during follow-up. Conclusion: PEHC is a degenerative disease of peripheral retina that is seen in older patients, and signs of age-related macular degeneration (AMD) may accompany this pathology. Especially in patients with AMD findings, the peripheral retina must be evaluated carefully for existing PEHC lesions.