When we talk about brain tumors, we can identify different types. We talked about it by Prof. Federico Pessina, neurosurgeon and lecturer at Humanitas University, giving attention to an innovative surgical technique, designed to remove localized tumors to the basicranium arriving to the area of surgery without passing through the healthy brain tissue.
Different types of tumours
Meningiomas: they develop from the meninges, i.e. in the tissues surrounding the external part of the brain. In most cases they are diagnosed accidentally, because they are small and asymptomatic, while in other cases the symptomatology consists of epileptic seizures and, in very rare cases if they are large, they manifest themselves in focal neurological deficits or behavioural and cognitive alterations; gliomas: originate from glial cells (which have functions of support and nutrition of neurons). They tend to occur at the ‘young-adult’ age between 18 and 50 years, with epileptic seizures. They may have a low degree of malignancy but also asymptomatic or high degree of malignancy. If they occur in adults or the elderly, they manifest themselves as epileptic crises, with neurological deficits – such as motor and coordination difficulties – or cognitive deficits (memory difficulties, concentration). Another type of brain tumour is neurinoma: benign neoplasms of the nerve sheaths, often located at the base of the skull, the most common affecting the auditory nerve and manifest themselves with tinnitus, hearing loss and dizziness; finally, cavernous angiomas, these are venous malformations (an agglomeration of vessels), related to epileptic or haemorrhagic symptoms; often they can experience small asymptomatic bleeding that can only be detected by magnetic resonance imaging.
An innovative and mini-invasive technique
Meningiomas, gliomas, neurinomas, cavernous angiomas, we have seen the many and different types of tumors and masses that develop in the brain areas, highly delicate areas where the surgeon has to operate with particular attention to vessels, nerves and brain tissue that could suffer damage.
“It can be difficult to safely access tumors located in deep regions at the level of the middle and posterior basicranium,” spiked the neurosurgeon. “In this region the pathologies that can be found are basically meningiomas, gliomas, trigeminal neurinomas and brainstem angiomas. In order to reach this region, neurosurgeons, following the path of otorhinolaryngologists and their experience in surgery of the petrosa rock, began to work on the deep regions of the temporal bone, developing the technique of anterior petrosectomy according to Kawase”.
The goal was to reach the mass to be removed, trying to avoid delicate areas of the brain. “Starting from the temporal bone you can have access to deep regions in relative safety, without manipulation of healthy brain tissue, cranial nerves and vessels, as happens with a traditional approach, arriving directly on the mass to be removed”, clarified Dr. Pessina.
“With anterior petrosectomy we work in a less noble tissue, also rich in important anatomical structures but with relatively fixed reference points on their position, which can be identified, exposed and preserved. Passing through the bone, we get to directly open the hard mother that covers the brain just above the tumor, without having healthy brain tissue interposed between the surgeon’s scalpel and the lesion to be removed. This technique, initially used only for meningiomas and neurinomas, has thus also been applied to glial tumours and cavernous angiomas located in the deep region of the brain stem. This is a very complex approach, which requires a deep knowledge of the anatomical base of the skull and a confidence from a technical point of view in access: you meet important structures of facial motility, hearing and vascular, not to be damaged, but that can be well identified and preserved so that the softness, ie the possible side effects of the intervention, is much lower than the classic approach.