Cerebrospinal fluid is a clear fluid that surrounds and protects the brain. During surgery for brain tumors, neurosurgeons often need to open the covering of the brain (the dura) to reach the tumor. At the end of the operation, this covering is carefully closed again. In some cases, the closure might not be completely adequate leading to cerebrospinal fluid leak. This leakage may collect under the scalp or flow out through the surgical wound. When this happens, the surgical wound may not heal properly, and the risk of infection can increase. These complications can delay recovery and may postpone additional treatments, such as radiotherapy or chemotherapy, that are often needed after brain tumor surgery. Although cerebrospinal fluid leakage is less common after supratentorial craniotomy (surgery on the upper part of the brain) than after other types of brain surgery, it remains a challenging complication and has not been well studied in this group of patients. The aim of this study is to determine how often cerebrospinal fluid leakage occurs after supratentorial craniotomy for intracranial tumors, identify factors that increase the risk of leakage, and evaluate how these leaks are managed. Understanding these factors may help reduce the occurrence of cerebrospinal fluid leakage and improve postoperative recovery in the future.

Cerebrospinal fluid is a fluid that circulates within the subarachnoid space between the brain surface and the meningeal layers, providing mechanical protection and metabolic support to the central nervous system. During neurosurgical procedures for intracranial tumors, opening of the meningeal layers, including the dura mater, is routinely required to access deeper cerebral structures. At the conclusion of surgery, meticulous dural closure is performed to restore a watertight barrier. However, in certain cases, dural reconstruction may be insufficient, resulting in postoperative cerebrospinal fluid leakage.

Cerebrospinal fluid leakage may manifest as accumulation of fluid beneath the scalp tissues or as external drainage through the surgical wound margins. The presence of cerebrospinal fluid leakage compromises normal wound healing and increases the risk of postoperative complications, including superficial and deep surgical site infections. These complications may delay wound healing, prolong hospitalization, and affect the timing of postoperative adjuvant therapies such as radiotherapy or chemotherapy in patients with intracranial tumors. Although cerebrospinal fluid leakage is more commonly associated with infratentorial procedures, it remains a significant and challenging complication following supratentorial craniotomy. Despite its clinical relevance, cerebrospinal fluid leakage after supratentorial tumor surgery is relatively under investigated, and data regarding its incidence, risk factors, and optimal management strategies remain limited. This prospective observational study aims to evaluate the incidence of cerebrospinal fluid leakage following supratentorial craniotomy for intracranial tumors, identify patient and surgery related risk factors, and assess the effectiveness of various management and treatment modalities. All patients undergoing supratentorial craniotomy for intracranial tumor resection will be prospectively observed, and those who develop postoperative cerebrospinal fluid leakage will be identified and analyzed. Data collection will include tumor related anatomical characteristics, dural closure techniques, materials used for dural reconstruction, and therapeutic interventions employed for the management of cerebrospinal fluid leakage. Patients will be followed for a period of six weeks postoperatively, corresponding to the typical timeframe for initiation of adjuvant oncological treatment. The findings of this study aim to improve understanding of cerebrospinal fluid leakage in supratentorial craniotomies and may contribute to the development of strategies to reduce its incidence and associated complications in the future.

Inclusion Criteria:

• Male or female at least 18 years old
• Qualified for a craniotomy due to supratentorial intracranial tumor

Exclusion Criteria:

• Revision surgery due to recurrent brain tumor
• Emergency neurosurgical procedure

Patients qualified for supratentorial craniotomy for intracranial tumor.