Ultrasonographic characteristics of active ocular toxoplasmosis / Achados ultrassonográficos em toxoplasmose ocular ativa

ABSTRACT Purpose: To evaluate ophthalmic ultrasonographic findings associated with active ocular toxoplasmosis. Methods: Forty-seven eyes with active ocular toxoplasmosis in 47 patients were subjected to ocular ultrasonography using the transpalpebral technique (10-MHz transducer) and fundus photography. Patient medical records were retrospectively reviewed. Results: Ocular ultrasonography revealed vitritis, posterior vitreous detachment, retinal wall thickening, and non-rhegmatogenous retinal detachment in 47 (100%), 36 [76.6%; partial in 12 (25.5%) and total in 23 (48.9%)], 12 (25.5%), and 5 eyes (10.6%). Thirty-five of the 36 eyes with posterior vitreous detachment (97.2%) exhibited posterior hyaloid thickening; moreover, adhesion to the exudative lesion and vitreoschisis were observed in 4 (11.1%) and 12 eyes (25.5%), respectively. Ultrasonography detected the location of the exudative focus in 12 eyes (25.5%). Conclusion: Ultrasonography is helpful for detecting important intraocular findings of acute ocular toxoplasmosis that can be hindered by medial opacity or posterior synechiae.

RESUMO Objetivo: Avaliar os achados da ultrassonografia na toxoplasmose ocular ativa. Métodos: Quarenta e sete olhos com toxoplasmose ocular ativa em 47 pacientes foram submetidos à ultrassonografia ocular pela técnica transpalpebral (transdutor de 10 MHz) e fundo de olho. Os prontuários médicos foram revistos retrospectivamente. Resultados: A ultrassonografia ocular revelou vitreíte, descolamento vítreo posterior, espessamento da parede da retina e descolamento de retina não regmatogênico em 47 (100%), 36 [76,6%; parcial em 12 (25,5%) e total em 23 (48,9%)], 12 (25,5%) e 5 olhos (10,6%). Trinta e cinco dos 36 olhos com descolamento vítreo posterior (97,2%) exibiram espessamento hialoide posterior; além disso, a adesão à lesão exsudativa e vitreosquise foi observada em 4 (11,1%) e 12 (25,5%), respectivamente. A ultrassonografia detectou a localização do foco exsudativo em 12 olhos (25,5%). Conclusão: A ultrassonografia é útil na detecção de importantes achados intra-oculares de toxoplasmose ocular aguda que podem ser prejudicados pela opacidade medial ou sinéquia posterior.

The Use of Contrast-Enhanced Color Doppler Ultrasound in the Differentiation of Retinal Detachment from Vitreous Membrane

OBJECTIVE: To compare the clinical utility of contrast-enhanced color Doppler US in the differentiation of retinal detachment (RD) from vitreous membrane (VM) with that of various conventional US modalities, and to analyze the enhancement patterns in cases showing an enhancement effect. MATERIALS AND METHODS: In 32 eyes examined over a recent two-year period, RD (n=14) and VM (n=18) were confirmed by surgery (n=28) or clinical follow-up (n=4). In all cases, gray-scale, color Doppler, and power Doppler US were performed prior to contrast injection, and after the intravenous injection of Levovist (Schering, Berlin) by hand for 30 seconds at a dose of 2.5 g and a concentration of 300 mg/mL via an antecubital vein, contrast-enhanced color Doppler US was performed. At Doppler US, the diagnostic criterion for RD and VM was whether or not color signals were visualized in membranous structures. RESULTS: Diagnostic accuracy was 78% at gray-scale US, 81% at color Doppler US, 59% at power Doppler US, and 97% at contrast-enhanced color Doppler US. The sensitivity of color Doppler US to color signals in RD increased from 57% to 93% after contrast enhancement. The enhancement patterns observed were signal accentuation (n=3), signal extension (n=2), signal addition (n=3), and new signal visualization (n=5). CONCLUSION: Contrast-enhanced color Doppler US was the most accurate US modality for differentiating RD from VM, showing a significantly increased signal detection rate in RD.