Giant intracranial cavernomas: our experience

Introduction. Cavernoma is a benign vascular hamartoma characterized by slow flow and vessels without elastin or smooth muscle. Most cavernomas usually range in size from a few mm to 2 cm. Larger cavernoma are referred to as giant, even if no threshold dimension has been officially accepted for giant cavernomas (GC). Patients with cavernomas can present with seizures (40-50%), focal neurological deficits (20%) or can be asymptomatic. In the rare case of GC, more often the clinical presentation can be characterized by a huge bleeding with severe intracranial hemorrhage or by focal neurological deficits caused by the mass effected of GC. GC can occur at any age but are most common in the 3rd and 4th decade of life. Occasionally, there is a family history of cavernomas. Almost all cavernomas are associated to microhemorrhage although bleeding is usually aymptomatic. Risk of bleeding is increased for posterior fossa lesions, in females and in those lesions with a previous hemorrhage. GC carry a higher risk of bleeding. Objects. Aim of the study was the evaluation of the correct management of patients with GCs. We report 3 cases of giant intracranial cavernous angiomas. The neuroradiological aspects and the surgical treatment are discussed, together with a review of the literature. Materials and Methods. In our experience, we managed 3 patients affected by giant intracranial cavernomas. They were 2 females and 1 male with a ratio of 2:1. The mean age was 31 years old. In one patient multiple intracranial cavernomas were found. The site of cavernomas was the left sylvian fissure in the case of a 32- year-old woman with a 2 months history of right hemiparesis; the parietal convexity in an asymptomatic 19- year-old man, who had been previously operated for a large cavernomas of the left basal ganglia; the right frontal pole in a 42-year-old woman with a 3 months history of headache. In all patients a brain MRI wasperformed documenting in all cases the presence of a reticulated core of mixed signals representing blood in various states of degradation, surrounded by a hypointense halo due to hemosiderin on T2 weighted MRI images. Results and conclusions. Patients were operated through a craniotomy planned with the use of the neuronavigator, and the presurgical navigation with the magnetic transcranial stimulation was performed in 2 cases. It allowed a precise localization of the lesion preserving the eloquent areas. In all patients a complete removal of the lesion was achieved. The postoperative course was uneventful and all patients were discharged with no postoperative neurological deficits. Intracranial GC are rare. Only 16 cases have been so far reported in the literature. The mechanism by which an intracranial cavernoma enlarges is probably consequent to recurrent bleeding, followed by organization of the clot, pseudocapsule formation and secondary expansion. It is important to make a differential diagnosis with large intracranial tumors. Since imaging appearance of GC is variable, the possibility of CMs should be considered in the case of a large tumor. GC represents a surgical challenge, especially in those cases localized in deep or eloquent areas. The best management has to be tailored case by case, taking into considerations several factors such as the age of the patient, the clinical presentation, the site and previous bleeding. Surgery with complete removal of the lesion represents the only curative treatment and should be indicate in all cases of young symptomatic patients when the lesion is superficial. In case of old patients, with deep lesions or when the patient is asymptomatic, the choice has to be taken singularly. The use of modern tools, such as intraoperative neuronavigator and presurgical transranial magnetic stimulation with preoperative mapping of eloquent areas, allows to perform surgery with low risks, also in patients with large intracranial cavernomas in eloquent areas.