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Background: Optical coherence tomography has emerged as a new tool for quantifying axonal loss in multiple sclerosis (MS). A reduction in retinal nerve fiber layer (RNFL) thickness is correlated with Expanded Disability Status Scale score and brain atrophy. Objective: To investigate RNFL and macular volume measurements using optical coherence tomography in the clinically isolated syndrome population. Design: Prospective case series. Settings: Neurologic clinics at the university hospitals of Lille and Strasbourg (France). Participants: Fifty-six consecutive patients with clinically isolated syndrome (18 with optic neuritis and 38 without optic neuritis) and 32 control subjects. Main Outcome Measures: Macular volume and RNFL thickness. Results: Mean (SD) overall RNFL thickness (98.98 [10.26] µm) and macular volume (6.86 [0.32] µm 3) in the clinically isolated syndrome population were not significantly different compared with the controls (98.71 [9.08] µm and 6.92 [0.38] µm 3 , respectively). No link was noted between atrophy of the RNFL or macula and conversion to MS at 6 months. Conclusions: Optical coherence tomography does not reveal retinal axonal loss at the earliest clinical stage of MS and does not predict conversion to MS at 6 months.

The KIT gene encodes c-kit, a transmembrane receptor that has tyrosine kinase activity and plays a role in haematopoiesis, gametogenesis and melanogenesis. The c-kit protein is found in normal cutaneous and choroidal melanocytes, and there is evidence that expression is lost in melanoma. Expression of c-kit was analysed in 57 paraffin-embedded sections of choroidal melanoma specimens and three choroidal melanoma cell lines using immunochemistry and Western blotting. Of the tumour specimens, 75% stained positively for c-kit with a membrane pattern of reactivity. Of the six patients who underwent proton beam therapy before enucleation, five tumours exhibited no c-kit immunoreactivity and the other tumour demonstrated weak staining. Of the three melanoma cell lines used, c-kit expression was observed in only one. No correlations between c-kit positivity and parameters such as cell type, largest macroscopic tumour dimension, scleral invasion or pigmentation were observed. In contrast, a significant positive association was found between c-kit staining and mitotic activity (P = 0.02). However, c-kit expression did not significantly influence survival when evaluated by univariate analysis. In conclusion, c-kit is expressed in most choroidal melanoma tumours. Further analysis should provide new insights into the mechanisms underlying the molecular and cellular changes in choroidal melanomas.

Inoculation of native or human CD20-transfected murine 38C13 cells in the vitreous or the brain of immunocompetent mice provides useful novel models for evaluating the biology and treatment of PIOL and PCNSL. Intravitreal and intracerebral rituximab injections reduced tumor occurrence and growth in each model.

Toxoplasma gondii infection is an important cause of chorioretinitis in Europe and the United States.Ophthalmological examination and a good clinical response to adequate therapy mainly support ocular toxoplasmosis diagnosis. However, clinical diagnostic may be difficult in some atypical cases. In these cases, laboratory confirmation, based on detection of local specific antibodies and parasite DNA by conventional PCR, is therefore important to confirm the disease etiology. More recently, real-time PCR has been developed to improve prenatal congenital toxoplasmosis diagnosis. We therefore examined the diagnostic value of quantitative real-time PCR for the detection of T. gondii in aqueous humor samples, associated with quantification of human ␤-globin to control sample quantitative quality, by using a double fluorescence resonance energy transfer hybridization probes system with a double fluorescence reading. Of the 23 the clinically toxoplasmosis suspect patients, 22 showed serological evidence of exposure to Toxoplasma; one had a serological profile indicative of active infection. The analysis of paired aqueous humor and serum samples revealed an intraocular antibody production in 9 of 23 cases (39.1%). The quantitative real-time PCR revealed positive and high parasite numbers and high Toxoplasma/human genome ratios in three cases. Furthermore, PCR was the only positive confirmatory test in two cases (11.1%). None of the patients included in the control group (n ‫؍‬ 7) had evidence of either local specific antibody production or T. gondii DNA detection, suggesting a good relative assay specificity. On the whole, quantitative real-time PCR appears to be useful for diagnosing atypical ocular toxoplasmosis presentations.