Helmetlike skull deformity with a large arachnoid cyst.
BACKGROUND
It is not difficult to find localized skull ballooning or macrocrania in patients with intracranial arachnoid cysts. However, there have been no previous reports regarding large localized skull protuberant deformities resembling a war helmet. The authors report with a review of literature a case of an adult with helmetlike skull deformity resulting from a large supratentorial arachnoid cyst.


METHODS
A 35-year-old man presented with a large head deformity since his early childhood that had been the result of gradual progression from infantile macrocrania. He also had mental retardation, sixth cranial nerve palsy with recent aggravation of headache, reduced activity, poor voiding control, and walking disturbance. Magnetic resonance imaging of the head showed hydrocephalus with a large supratentorial arachnoid cyst located in the bilateral parietooccipital area compressing the hemisphere anteriorly, and the tentorium and cerebellum inferiorly. Magnetic resonance venogram demonstrated low-lying short transverse and lateral sinuses, and the superior sagittal sinus and falx were displaced to the right side. Radioisotopic cisternogram showed nonfilling of the isotope in the bilateral parietooccipital area. Cerebrospinal fluid pressure measured by lumbar puncture was 17 cm H(2)O. We tentatively diagnosed the condition as normopressure hydrocephalus with a large supratentorial arachnoid cyst. His headache, reduced activity, poor voiding control, and walking disturbance improved after a cystoperitoneal shunt.


CONCLUSIONS
This might suggest that large arachnoid cysts found in childhood should be treated for prevention of skull deformity and late aggravation of increased intracranial pressure.
Park
Seoung Woo
SW
Department of Neurosurgery, Kangwon National University College of Medicine, Chunchon 200-701, Korea.
Cho
Ki Hong
KH
Shin
Yong Sam
YS
Kim
Se Hyuk
SH
Ahn
Young Hwan
YH
Cho
Kyung Gi
KG
Huh
Ji Soon
JS
Yoon
Soo Han
SH
D000328:Adult; D016080:Arachnoid Cysts / Q000000981:diagnostic imaging / Q000473:pathology*; D006801:Humans; D006849:Hydrocephalus / Q000000981:diagnostic imaging / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D011877:Radionuclide Imaging; D012886:Skull / Q000000981:diagnostic imaging / Q000473:pathology*