Ununsual manifestations of neurocysticercosis in MR imaging: analysis of 172 cases

Abstract

-Purpose: The typical manifestations of neurocysticercosis are described widely in the literature. The purpose of this study is to demonstrate the uncommon presentations of different forms of neurocysticercosis in MR imaging. Method: A retrospective analysis of 172 cases of neurocysticercosis in MR studies was carried out over a period of 13 years. One hundred and four males and 68 females with a mean age of 32 ± 3.7 years were studied. The studies were performed on 1.5 T GE MR units and T1 was used before and after gadolinium injection, T2 and gradient-echo (T2*) sequences. Results: The authors divided the unusual manifestations of neurocysticercosis into: intraventricular, subarachnoid, spinal, orbital, intraparenchymatous, and reactivation of previously calcified lesions. The results obtained were: intraparenchymatous 95 cases (55.23%); intraventricular 27 cases (15.69%); subarachnoid 20 cases (11.63%); spinal 6 cases (3.49%); orbital 1 case (0.58%); reactivated lesion 1 case (0.58%); association of intraventricular and intraparenchymatous 12 cases (6.98%); association of subarachnoid and intraparenchymatous 6 cases (3.49%); association of subarachnoid and intraventricular, 4 cases (2.32%). Conclusion: MR imaging is a sensitive and specific method in the analysis of different forms of unusual manifestations of neurocysticercosis, which should appear in the differential diagnosis of parenchymal, ventricular, spinal, cisternal, and orbital lesions.KEY WORDS: cysticercosis, parasites, MRI, subarachnoid space. Manifestações incomuns na ressonância magnética da neurocisticercose: análise de 172 casosRESUMO -Objetivo: as manifestações típicas da neurocisticercose já são bem conhecidas. O papel deste estudo foi demonstrar os aspectos incomuns da neurocisticercose na ressonância magnética. Método: foram analisados 172 casos de ressonância magnética de neurocisticercose na Med Imagem num período de 13 (treze) anos em aparelhos GE de 1.5T Signa (Horizon, LX e CVI). Dos casos analisados, foram diversas as formas de apresentação, incluindo intraventricular, intraespinhal, cisternal, orbital, formas atípicas parenquimatosas (simulando tumores), forma miliar e evolução não usual (reativação). Conclusão: A ressonância magnética é método sensível e específico na avaliação das numerosas formas de apresentação atípica da neurocisticercose, as quais devem constar no diagnóstico diferencial de lesões intraventriculares, cisternais, orbitárias e parenquimatosas. PALAVRAS-CHAVE: cisticercose, parasitas, ressonância magnética, espaço subaracnóide.

Giant Neurocysticercosis Cyst in the Cerebellar Hemisphere-Case Report-

“…The usual locations of neurocysticercosis cysts in the posterior fossa are the fourth ventricle, cerebellopontine angle cistern, cisterna magna, medulla oblongata and, less frequently, the cerebellar vermis. 2,3,14,19) The general absence of neurocysticercosis cysts in the cerebellar hemisphere may result from the relatively poor blood circulation compared with the cerebral hemisphere, so the probability of seeding is low, as in the cases of metastatic tumors.…”

Uncommon Clinical Manifestations of Cysticercosis

“…In the posterior fossa, NCC can involve the fourth ventricle, cerebellopontine angle cistern, cisterna magna and rarely, the cerebellum [64,65] .Cysticercosis affecting one of the abovementioned anatomical structures are grouped under the name of NCC of the posterior fossa (PFNCC).…”

“…[220] Other authors also divided the unusual manifestations of neurocysticercosis into: intraventricular, subarachnoid, spinal, orbital, intraparenchymatous, and reactivation of previously calcified lesions and they reported frequencies of 15.69% of intraventricular presentations, subarachnoid: 11.63%; spinal: 3.49%; orbital: 0.58% and reactivated lesion: 0.58% and the frequencies for association of intraventricular and intraparenchymatous: 6.98%; association of subarachnoid and intraparenchymatous: 3.49; and association of subarachnoid and intraventricular: 2.32%. [225] but they did not include other presentations already mentioned in this chapter.…”

Comparação entre diferentes sequências de ressonância magnética na detecção de calcificações em pacientes portadores de neurocisticercose

“…No SNC as larvas encistadas acometem mais comumente o parênquima, mas podem também ser encontradas nos ventrículos e no espaço subaracnóideo, ou numa associação entre eles. Menos comumente pode ser encontrada na coluna, globo ocular e tecidos extraneurais [85][86][87] .…”

“…O cisto móvel pode promover hidrocefalia por obstrução mecânica. Em casos de obstrução aguda, pode levar à morte 86,93 .…”