Isolated tectal cavernomas: A comprehensive literature review with a case presentation

Treatment of a Large Hemorrhagic Midbrain Cavernoma Within the Silvian Aqueduct in a Five-Year-Old Girl-A Case Report

Brain stem cavernomas are exceedingly rare in pediatric populations, with limited literature addressing their natural history, treatment guidelines, and counseling. We report the case of a 5-year-old girl presenting with acute neurological symptoms, including diplopia, gait ataxia, headache, and altered consciousness. Initial imaging revealed obstructive hydrocephalus caused by a hemorrhagic lesion near the pineal region. After emergency external ventricular drainage (EVD), most symptoms resolved except for diplopia. A subsequent MRI suggested a space-occupying hemorrhagic cyst in the tectal lamina, leading to endoscopic third ventriculostomy (ETV). During ETV, a large hemorrhagic mass at the aqueduct entrance was identified but not removed due to its fragility. Following ETV, the patient improved rapidly and was discharged. However, she was readmitted with recurrent symptoms and altered consciousness. An emergency MRI indicated a progressive hemorrhagic mass lesion compressing the midbrain, necessitating surgical intervention. The patient underwent suboccipital craniotomy using a telovelar approach. The intraoperative findings included cavernoma-like tissue within the aqueduct, which was successfully resected. Histopathology confirmed hemorrhagic and angiomatous tissue, excluding a primary brain tumor. Postoperatively, the patient showed significant, progressive neurological improvement, with mild internuclear strabism, trunk ataxia, and fatigue at the last follow-up. Six months later, a follow-up MRI and cerebral angiography showed no cavernoma remnants but identified a midbrain deep venous anomaly. This case underscores the feasibility of the microsurgical resection of midbrain cavernomas in symptomatic pediatric patients, highlighting the importance of the thorough assessment of atypical hemorrhagic midbrain lesions to exclude rare vascular malformations from differential diagnoses.

Crossed Brainstem Syndrome of the Tectal Plate's Inferior Colliculus Revealing Quadrigeminal Midbrain Cavernous Malformation

Cavernous malformations are low-flow fragile vascular lesions prone to extralesional bleeding that can occur in the cerebral hemispheres, the brainstem, or the spinal cord. This paper reports the case of a 32-year-old right-handed man with acute-onset headaches associated with right-sided tinnitus, right-sided hemianesthesia, and binocular diplopia related to cranial nerve IV palsy. Neuroimaging displayed left-sided isolated cavernous malformation of the inferior tectal plate, with evidence of extralesional bleeding. Clinical presentation and neuroimaging features were compatible with inferior colliculus crossed brainstem syndrome. Thanks to clinical improvement and the absence of mass effect on neuroimaging, surgical intervention was delayed. At the 3-month follow-up consultation, symptoms had improved aside from diplopia, which required wearing prism eyeglasses. Tectal cavernous malformations account for 18% of midbrain cavernomas. It was explained that surgical excision using the supracerebellar infratentorial approach would be performed within 2 months after a second extralesional bleeding episode causing disabling symptoms.