Posterior fossa arteriovenous malformations: Significance of higher incidence of bleeding and hydrocephalus.
OBJECTIVE
Hydrocephalus associated with different types of intracranial arteriovenous malformations (AVMs) has been scarcely studied. In the present report we investigate this association with posterior fossa AVMs (pfAVMs). We hypothesized that there is an increased risk of hydrocephalus and required permanent cerebrospinal fluid (CSF) shunt in patients with pfAVMs that may be linked to the increased risk of bleeding of these lesions. We also review the factors associated with this increased risk of hemorrhagic presentation and we assess how it affects management strategies and functional outcomes in these patients.


METHODS
Out of a prospective registry of 374 patients with brain AVMs diagnosed in our center from 1993 to 2013, 60 (16%) had a pfAVM. We described these patients' demographics, their AVM characteristics, clinical presentation, and hydrocephalus incidence and compared the results with those of the supratentorial AVM (spAVM) patients recorded during the same period.


RESULTS
Out of the 60 patients with pfAVMs, 10 (16.7%) presented AVMs located in the brainstem. Hemorrhagic presentation (49/60; 82%) was significantly higher in pfAVMs than in spAVMs (122/314; 38.8%; p<0.05). Hydrocephalus was a common complication in pfAVM patients who had a statistically significant higher need for both temporary external ventricular drain (EVD) (6.7 vs. 20%; p<0.05) and permanent CSF shunts (3.5 vs. 20%; p<0.05). The initial mortality was high (12/60; 20.3%) and half of these patients died before any treatment option could be offered. However, out of those who survived, 70% (42/60) had already shown good clinical outcome at the 6-month follow-up.


CONCLUSIONS
Hemorrhagic presentation and hydrocephalus have a higher incidence in pfAVM patients, which initially results in more neurological deficits and an elevated mortality even before receiving any treatment. However, a large number of survivors present good functional outcomes at early follow-up, justifying an aggressive management strategy with microsurgery as the first treatment option in most cases, and radiosurgery as an alternative, especially in brainstem AVMs.
Department of Neurological Surgery, Vall d'Hebron University Hospital, Paseo Vall D'Hebron 119-129, 08035 Barcelona, Spain; Neurotraumatology and Neurosurgery Research Unit (UNINN), Vall d'Hebron Research Institute, Universitat Autonoma de Barcelona (UAB), Barcelona, Spain. Electronic address: ramtorne@me.com.
Ramon
R
Torné
Department of Neurological Surgery, Vall d'Hebron University Hospital, Paseo Vall D'Hebron 119-129, 08035 Barcelona, Spain.
Ana
A
Rodríguez-Hernández
Department of Neurological Surgery, Vall d'Hebron University Hospital, Paseo Vall D'Hebron 119-129, 08035 Barcelona, Spain; Neurotraumatology and Neurosurgery Research Unit (UNINN), Vall d'Hebron Research Institute, Universitat Autonoma de Barcelona (UAB), Barcelona, Spain.
Fuat
F
Arikan
Department of Neurological Surgery, Vall d'Hebron University Hospital, Paseo Vall D'Hebron 119-129, 08035 Barcelona, Spain; Neurotraumatology and Neurosurgery Research Unit (UNINN), Vall d'Hebron Research Institute, Universitat Autonoma de Barcelona (UAB), Barcelona, Spain.
Fabián
F
Romero-Chala
Neurotraumatology and Neurosurgery Research Unit (UNINN), Vall d'Hebron Research Institute, Universitat Autonoma de Barcelona (UAB), Barcelona, Spain.
Marta
M
Cicuéndez
Department of Neurological Surgery, Vall d'Hebron University Hospital, Paseo Vall D'Hebron 119-129, 08035 Barcelona, Spain; Neurotraumatology and Neurosurgery Research Unit (UNINN), Vall d'Hebron Research Institute, Universitat Autonoma de Barcelona (UAB), Barcelona, Spain.
Jordi
J
Vilalta
Department of Neurological Surgery, Vall d'Hebron University Hospital, Paseo Vall D'Hebron 119-129, 08035 Barcelona, Spain; Neurotraumatology and Neurosurgery Research Unit (UNINN), Vall d'Hebron Research Institute, Universitat Autonoma de Barcelona (UAB), Barcelona, Spain.
Juan
J
Sahuquillo
D000293:Adolescent; D000328:Adult; D000368:Aged; D001933:Brain Stem / Q000000981:diagnostic imaging / Q000601:surgery*; D002531:Cerebellum / Q000000981:diagnostic imaging / Q000601:surgery*; D002557:Cerebrospinal Fluid Shunts; D002648:Child; D002675:Child, Preschool; D004621:Embolization, Therapeutic; D005260:Female; D006801:Humans; D006849:Hydrocephalus / Q000209:etiology*; D007223:Infant; D002538:Intracranial Arteriovenous Malformations / Q000150:complications / Q000000981:diagnostic imaging / Q000601:surgery*; D020300:Intracranial Hemorrhages / Q000000981:diagnostic imaging / Q000209:etiology / Q000601:surgery*; D008297:Male; D008866:Microsurgery; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies; D016634:Radiosurgery; D012042:Registries; D012422:Rupture, Spontaneous; D013345:Subarachnoid Hemorrhage / Q000000981:diagnostic imaging / Q000209:etiology / Q000601:surgery*; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D055815:Young Adult
Associated aneurysms; Hemorrhagic presentation; Hydrocephalus; Posterior fossa AVM; Shunt