Authors:
Y. B, S. Kemaloglu, H. Nazaroglu, A. Uyar, C. Akg, M. Simsek; Diyarbakir/TR
Results
Most of the patients were children, 13 patients aut of 18 ( 72.2 % ) between 7 and 15 years of age. There was a substantial prevalence of male patients-12 cases ( 66.7 % ). Among our patients, there were 17 cases of cystic echinococcosis ( E.granulosis ) and 1 case of alveolar echinococcosis ( E. multilocularis ). The most common clinical findings were headache, vomiting, seizures and visual disturbances. Papilloedema was seen in 14 patients ( 77.7 % ). There were extracerebral organ involvement in 6 cases.In our series most of the cases were single lesion, 16 patients out of 18 ( 88.9 % ) and two of them were complicated or infected cysts, other two cases ( 2 patients out of 18, 11.1 % ) had multiple lesions. In single-lesion cystic echinococcosis cases, lesions were located as follows: 3 in the parietooccipital region, 4 in the temporoparietal region, 3 in the frontotemporoparietal region, 1 in the temporoparietooccipital region, 2 in the occipital lobe, 2 in the frontotemporal region and 1 in the posterior fossa, (in the fourth ventricle). In one of the multiple cystic echinococcosis cases, there were 25 cystic lesions in the left temporoparietooccipital region and was labeled as a gigantic intracranial hydatid cyst ( 95x90x75mm ). CT and MR scans showed a large mass of multiple cystic space-occupying lesions in the left temporo-parieto-occipital region, with midline shift to the right hemisphere. No peripheral edema was noted around the cysts
( Fig. 1A), ( Fig. 1B), hydatid cyst removed at operation ( Fig. 2) (8).In the other patient with multiple cystic echinococcosis, there were 9 lesions in the left parietooccipital region.The size of the cystic echinococcosis lesions ranged from 1 to 10cm .Ten cystic echinococcosis cases were located in the left cerebral hemisphere, while 6 cystic echinococcosis cases were located in the right cerebral hemisphere. The parietal lobe was the commonest lobe affected. In cerebral alveolar echinococcosis case the location was in the right parietooccipital region with 11x8.5 cm diameter in size. On CT, cerebral cystic echinococcosis lesions were seen as large, smooth, thin-walled, spherical well-defined, nonenhancing homogeneous lesions, which have an inner density similar to CSF (Figs. 3A-B). MR demonstrated hypointense lesions on T1-weighted images and hyperintense lesions on T2-weighted images.The walls of the cysts hypointense on T1- and T2-weighted images (Figs. 4A-D) . No calcification, no surrounding edema, and no contrast enhancement were seen on CT and MR in non-complicated cystic echinococcosis lesions.One of our cases demonstrated multilocular cerebral hydatid cyst with extracalvarial extension in the left parietooccipital region. In this case CT examination revealed destruction and thining in the adjacent left parietal bone (9).One patient of our cases presented a single well-rounded cystic lesion in the right occipital region. The patient had been treated 6 months previously for a cerebral infarct in the left parietooccipital regions and a cystic lesion had not been present. Echocardiography identified a mass lesion on the left ventricular surface of the anterior mitral valve. Following cardic surgery, the diagnosis was confirmed as cardiac hydatidosis. It is presumed that the cardiac echinococcosis caused the cerebral infarct as a result of thromboembolism and the parasitic embolism grow into the opposite hemisphere. The cyst was obviously growing at a very fast Rate: the growth rate was 4.5 cm in 6 months (10).In two of our patients a surrounding hypodense area of perifocal edema and hyperdense complete or incomplete rim of contrast enhancement on CT scans were seen ( Fig. 5A). On MR, lesions were seen hyperintense on T2-weighted images, hypointense on T1- weighted images (Figs. 5B-D). These lesions were labeled as complicated or infected cysts (cysts with superadded pyogenic infection). One of them was presenting an aggressive hydatid disease that was attributed to cyst rupture during surgery. The cyst had germinal membrane detachment and herniated through weakness in pericyst and extended into temporal fossa.In case with cerebral alveolar echinococcosis, CT showed a well-defined, multiseptated mass consisted of solid and cystic components and calcifications ( Fig. 6A). On MR of the same patient, both on T1- and T2-weighted images, the mass showed a multicystic appearance with a central solid component and punctate calcifications with contrast enhancement of the wall, septatae and solid components (Figs. 6B-D). The solid components were iso/hyperintense in both T1 and T2-weighted images. The cystic components were hypointense in T1-weighted images and hyperintense in T2-weighted images. On T2-weighted images, solid portion of the lesion showed markedly small low signals correspending to calcification ( Fig. 6B).