Diffusion-weighted MR imaging of cystic lesions of neurocysticercosis: a preliminary study

Abstract

-Neurocysticercosis is an endemic disease in some developing countries. It has pleomorfic clinical and imaging findings, which are variable from patient to patient. In this preliminary note, we studied the magnetic resonance (MR) diffusion-weighted images (DWI) of sixteen patients presenting with cystic lesions of this disease diagnosed by clinical and laboratorial findings. All the lesions had hypointense signal and the similar apparent diffusion coeficient (ADC) values as the cerebrospinal fluid (CSF).KEY WORDS: neurocysticercosis, cystic lesion, MRI, diffusion images. Imagens por difusão de ressonância magnética em lesões císticas da neurocisticercose: estudo preliminarRESUMO -Neurocisticercose é doença endêmica em alguns países em desenvolvimento. Ela apresenta aspectos clínicos e de imagem que variam em cada paciente. Nesta nota preliminar expomos um estudo utilizando imagens ponderadas em difusão em dezesseis pacientes que apresentavam lesões císticas da neurocisticercose comprovada clínica e laboratorialmente. Todas as lesões examinadas apresentaram hiposinal com intensidade de sinal e valores de coeficiente de difusão aparente (CDA) similares ao do líquido cefalorraquiano.PALAVRAS-CHAVE: neurocisticercose, cistos intracranianos, ressonância magnética, imagem por difusão.

Imaging of cerebellopontine angle lesions: an update. Part 2: intra-axial lesions, skull base lesions that may invade the CPA region, and non-enhancing extra-axial lesions

“…On DWI, neurocysticercosis cysts have hypointense signal with an apparent diffusion coefficient similar to that of CSF. DWI may fail to detect racemose lesions [66]. As an alternative, noninvasive MR cisternography by means of FLAIR sequence acquired after a 5-min inhalation of 100% O 2 , which increases the signal of normal CSF, has been proposed as a robust technique to detect subarachnoid cysticercosis lesions [67].…”

Reduced Diffusion in Neurocysticercosis: Circumstances of Appearance and Possible Natural History Implications

“…The assumption that it represents the scolex comes from correlating with other sequences on which the scolex can be discerned. Previous work from Raffin et al 17 described this finding in 7 of 11 patients with NCC, but there was no mention of lesion count as a whole or per patient. Lesions in this study were also not classified according to the disease stage, though the authors stated that all patients had cystic lesions with signal intensity similar to that of CSF, with or without peripheral edema and/or enhancement, 17 which signals that their sample probably included lesions in the vesicular stage as well as in transitional forms between vesicular and colloidal vesicular stages, because even the lesions with edema or enhancement exhibited CSF signal in that study.…”

“…Previous work from Raffin et al 17 described this finding in 7 of 11 patients with NCC, but there was no mention of lesion count as a whole or per patient. Lesions in this study were also not classified according to the disease stage, though the authors stated that all patients had cystic lesions with signal intensity similar to that of CSF, with or without peripheral edema and/or enhancement, 17 which signals that their sample probably included lesions in the vesicular stage as well as in transitional forms between vesicular and colloidal vesicular stages, because even the lesions with edema or enhancement exhibited CSF signal in that study. We have expanded their observation to a larger sample population, classifying lesions according to NCC stages, including the depiction of a DWI hyperintense eccentric structure in lesions belonging to the colloidal vesicular stage, whose content was clearly distinct from CSF on FLAIR images.…”

“…12,13 Currently, there are few studies discussing the DWI findings in patients with NCC, but the limited studies demonstrate results that are variable and somewhat contradictory: Some studies disclosed hypointense signal within the cysts on DWI, similar to CSF, 7,14,15 whereas others have depicted the presence of various degrees of reduced diffusion. 16,17 However, the occurrence of reduced diffusion in patients with NCC has not been entirely understood, particularly regarding the location and relation to the stage of NCC. The aim of this study was to describe the DWI findings of a cohort of patients with NCC, emphasizing specifically the frequency and the stage of NCC lesions in which DWI abnormalities can be appreciated.…”

Avaliação das lesões císticas da neurocisticercose na difusão e espectroscopia de prótons pela ressonância magnética

“…Nesse estudo, o mapa e valores de CDA não foram calculados (63) . hipossinal na difusão (64) . (65) .…”