Cerebrospinal fluid leakage due to dural thinning after endoscopic pituitary tumor resection.

Sellar reconstruction is important for preventing cerebrospinal fluid (CSF) leakage after transsphenoidal pituitary surgery. This report describes how, despite standard sellar reconstruction, CSF exudation resulted from dural thinning at the anterior skull base, outside the intrasellar area manipulated during pituitary tumor resection. A 76-year-old man underwent endoscopic transsphenoidal surgery for a pituitary tumor extending toward the anterior skull base. After opening the sellar floor, intractable bleeding from the anterior intercavernous sinus occurred during bone removal at the anterior skull base. Pseudocapsule-based extracapsular resection was completed after stopping the bleeding. On the 10th postoperative day, the patient developed CSF rhinorrhea complicated by marked pneumocephalus, and emergency endoscopic repair of the CSF leak was performed. CSF leakage originated from the thinned dura at the anterior skull base located outside the intrasellar area manipulated during tumor resection. The thinned dural area at the anterior skull base coincided with the site of intractable bleeding of the anterior intercavernous sinus during bone removal in tumor resection. The thinned anterior skull base dura was covered with fascia, overlaid with fat, and closed with the nasoseptal flap. Endoscopic CSF leak repair was successful. Severe damage to the anterior intercavernous sinus can cause extensive exposure of the single-layered inner meningeal dura, where thinning might result in CSF exudation. Therefore, use of autologous tissues to cover and reinforce the severely damaged area of the anterior intercavernous sinus might help prevent postoperative CSF exudation.

Leukocyte- and Platelet-Rich Fibrin versus commercially available fibrin sealants in elective cranial surgery: a cost-effectiveness analysis.

BACKGROUND: Previous findings from a clinical trial demonstrated non-inferiority of Leukocyte- and platelet-rich fibrin (L-PRF) compared to commercially available fibrin sealants in preventing postoperative cerebrospinal fluid (CSF) leakage, necessitating intervention. This cost-effectiveness evaluation aims to assess the value-for-money of both techniques for dural closure in supratentorial and infratentorial surgeries. METHODS: Cost-effectiveness was estimated from a healthcare payer's perspective alongside a randomized clinical trial comprising 328 patients. The analysis focused on clinical and health-related quality of life (HRQOL) outcomes, as well as direct medical costs including inpatient costs, imaging and laboratory costs, and outpatient follow up costs up to twelve weeks after surgery. RESULTS: Clinical and HRQOL data showed no significant differences between L-PRF (EQ5D 0.75 ± 0.25, SF-36 63.93% ± 20.42) and control (EQ5D 0.72 ± 0.22, SF-36 60.93% ± 20.78) groups. Pharmaceutical expenses during initial hospitalization were significantly lower in the L-PRF group (€190.4, IQR 149.9) than in the control group (€394.4, IQR 364.3), while other cost categories did not show any significant differences, resulting in an average cost advantage of €204 per patient favoring L-PRF. CONCLUSION: This study demonstrates L-PRF as a cost-effective alternative for commercially available fibrin sealants in dural closure. Implementing L-PRF can lead to substantial cost savings, particularly considering the frequency of these procedures.

Intentional Dural Resection during en bloc Spinal Resection Could Provide a Secure Surgical Margin for Patients with Recurrent Spinal Tumors.

OBJECTIVE: It is always difficult to obtain a comfortable surgical margin for patients with recurrent malignant or invasive benign spinal tumors. Tumor intraspinal invasion and dural adhesion are the essential reasons. There are always residual tumor cells maintained at the edge of dura. Dural resection is a key point to obtain a comfortable surgical margin for such cases. Whether such patients benefit from this risky surgical procedure is unknown. This study aims to understand better the oncological results, associated risks, and neurological function of this risky surgical procedure. METHODS: We retrospectively reviewed clinical data from six consecutive patients who registered spinal tumors in our institute and underwent dural resection during en bloc spinal resection from June 2013 to May 2020. The demographic and perioperative data, oncological outcomes, complications, and neurological status were collected and analyzed. RESULTS: All six patients were followed up for 24 to 46 months (mean follow-up time: 32.8 months). Local recurrence was detected in one patient (1/6, 16.7%) at 36 months postoperatively and in five patients with no evidence of disease at the last follow up (survival rate 83.3%). Eleven complications occurred in four patients (66.7%), and the dural resection-related complications included only four cases of cerebrospinal fluid leakage (CSFL), which accounted for 36.4% (4/11) of all complications. Neurologic status evaluated by the Frankel grade showed improvement of one grade in one case and deterioration of one to two grades in five patients immediately after surgery. All deterioration cases recovered to the preoperative level 6 months after the operation. CONCLUSION: Dural resection is significant for patients with dura matter invaded by recurrent primary malignant or invasive benign spinal tumors with the purpose of clinical cure. This study demonstrated that in strictly selected cases, intentional dural resection could provide satisfying local control and long-term disease-free survival with acceptable complications and satisfying neurological function.

Frontal sinus reconstruction with overlapping sinus mucosa and vascularized pericranial flap Coverage after modified transbasal bifrontal craniotomy: Novel technique and clinical outcomes.

Background: The modified transbasal bifrontal craniotomy is a variant of the bifrontal craniotomy with a wider surgical corridor than the standard approach. There are several methods for frontal sinus repair in bifrontal craniotomy. This study reports a novel method for frontal sinus repair in the modified transbasal interhemispheric approach by precisely overlapping the frontal sinus mucosa margin (without frontal sinus mucosa exenteration) with packing the frontal sinus with povidone-soaked gel foam and covering it with a vascularized pericranial flap. Methods: In this case series, we retrospectively collected the clinical outcomes regarding cerebrospinal fluid (CSF) leakage, meningitis, and mucocele formation of patients who underwent modified transbasal bifrontal craniotomy at Vara Hospital. Results: From January 2016 to December 2021, 65 patients with anterior skull-base lesions were treated with a modified transbasal interhemispheric approach with frontal sinus repair by overlapping frontal sinus mucosa with gel foam packing and vascularized pericranium flap covering. There was no case of postoperative CSF leakage, meningitis, or mucocele formation during the follow-up period of 19.2 months (min 1, max 73). Conclusions: We demonstrated that the modified transbasal interhemispheric approach with frontal sinus repair using gel foam packing and pericranial flap is effective in preventing postoperative CSF leakage and meningitis.

Pneumocephalus resulting from traumatic pneumothorax and brachial plexus avulsion.

Background: Traumatic pneumocephalus is commonly encountered after basal skull fractures and rarely associated with blunt chest trauma. Here, we report a case of pneumocephalus caused by traumatic pneumothorax and brachial plexus avulsion. Case Presentation: A 20-year-old male was admitted to our hospital following a motorcycle accident with complete paralysis of the right upper limb. 2 days later, follow-up computed tomography revealed a slight right pneumothorax, pneumomediastinum around the neck, and intracranial air without skull fracture. Air migrates into the subarachnoid space through a dural tear caused by a brachial plexus avulsion. The pneumocephalus immediately improved after the insertion of a chest drain. Conclusion: Pneumothorax combined with brachial plexus avulsion could lead to pneumocephalus. Immediate chest drainage might be the best way to stop the migration of air; however, care should be taken to not worsen cerebrospinal fluid leakage.

Prevention of Cerebrospinal Fluid Leakage in the Anterior Transpetrosal Approach.

Background: The anterior transpetrosal approach (ATPA) is effective for reaching petroclival lesions, and it allows for complications such as impaired venous return and neuropathy to be resolved. However, there is still room for improvement regarding cerebrospinal fluid (CSF) leakage. Here, we aim to focus on describing specific preoperative, intraoperative, and postoperative countermeasures for preventing CSF leakage when using the ATPA. Methods: Eleven patients treated using the ATPA, who were treated at our hospital from June 2019 to February 2023, were included in this descriptive study. Preoperatively, we performed a 3D simulation of the opened air cells. Then, we classified patterns of dural closure into three types based on intradural manipulation and whether it involved opened air cells or not. Intraoperatively, we performed a dural closure that included the use of more-watertight sutures (DuraGen®) and an endoscope. Furthermore, temporal bone air cell volume measurements were performed to confirm the correlation between the volume and factors related to CSF leakage. Results: No postoperative CSF leakage was observed in any patient. The temporal bone air cell volumes significantly corelated with the air cells of the petrous apex, the high-risk tract in the petrous apex, and postoperative fluid collection in mastoid air cells. Conclusions: We have described countermeasures for preventing CSF leakage when using the ATPA. Preoperative simulations and the use of multiple-layered dural reconstructions with endoscopes could be considered more reliable methods for preventing CSF leakage when using the ATPA.

The Examination of Prognostic Factors and Treatment Strategies for Traumatic Cerebrospinal Fluid Leakage.

Introduction This study aimed to determine the optimal timing for surgical intervention and the prognostic factors of cerebrospinal fluid (CSF) leakage. Methods We identified 25 patients with probable CSF leaks from 472 consecutive patients with head trauma. In addition to baseline characteristics and findings on admission, injury severity score (ISS), abbreviated injury score (AIS), and other factors related to CSF leakage were considered. We analyzed the prognostic factors after setting the primary endpoint as the modified Rankin Scale (mRS) at the time of discharge to determine the appropriate timing for surgical intervention. Results Univariate analysis revealed significantly poorer prognoses for elderly patients (p<0.001) and cases with low Glasgow Coma Scale (GCS) levels (p=0.039) and high D-dimer levels (p=0.028), which was consistent with findings from the analyses of all patients with head trauma. We found that multiple traumas (AIS≥3 at two or more sites, p=0.047) and high lactate levels (p=0.043) were poor prognostic factors specific to CSF leakage cases, while a longer time to CSF leakage cessation was also associated with a poorer prognosis (median, six days versus 13 days, p=0.014). An evaluation of the time to closure found that spontaneous cessation occurred within 14 days in most cases. Conclusions Conservative medical treatment is the first choice for most cases of traumatic CSF leakage. Surgical intervention should be considered if leakage does not cease after 14 days post injury. Furthermore, severe multiple injuries and high lactate levels were poor prognostic factors specific to patients with CSF leakage.

Leukocyte- and platelet-rich fibrin in cranial surgery: a single-blinded, prospective, randomized controlled noninferiority trial.

OBJECTIVE: CSF leakage is a major complication after cranial surgery, and although fibrin sealants are widely used for reinforcing dural closure, concerns exist regarding their safety, efficacy, and cost. Leukocyte- and platelet-rich fibrin (L-PRF), an autologous platelet concentrate, is readily available and inexpensive, making it a cost-effective alternative for commercially available fibrin sealants. This study aimed to demonstrate the noninferiority of L-PRF compared with commercially available fibrin sealants in preventing postoperative CSF leakage in supra- and infratentorial cranial surgery, with secondary outcomes focused on CSF leakage risk factors and adverse events. METHODS: In a single-blinded, prospective, randomized controlled interventional trial conducted at a neurosurgery department of a tertiary care center (UZ Leuven, Belgium), patients undergoing elective cranial neurosurgery were randomly assigned to receive either L-PRF (active treatment) or commercially available fibrin sealants (control) for dural closure in a 1:1 ratio. RESULTS: Among 350 included patients, 328 were analyzed for the primary endpoint (44.5% male, mean age 52.3 ± 15.1 years). Six patients (5 in the control group, 1 in the L-PRF group) presented with CSF leakage requiring any intervention (relative risk [RR] 0.20, one-sided 95% CI -∞ to 1.02, p = 0.11), confirming noninferiority. Of these 6 patients, 1 (in the control group) presented with CSF leakage requiring revision surgery. No risk factors for reconstruction failure in combination with L-PRF were identified. RRs for adverse events such as infection (0.72, 95% CI -∞ to 1.96) and meningitis (0.36, 95% CI -∞ to 1.25) favored L-PRF treatment, although L-PRF treatment showed slightly more bleeding events (1.44, 95% CI -∞ to 4.66). CONCLUSIONS: Dural reinforcement with L-PRF proved noninferior to commercially available fibrin sealants, with no safety issues. Introducing L-PRF to standard clinical practice could result in important cost savings due to accessibility and lower cost. Clinical trial registration no.: NCT03812120 (ClinicalTrials.gov).

Effects of surface profile on porcine dural mechanical properties.

BACKGROUND: Cerebrospinal fluid leakage through the spinal meninges is difficult to diagnose and treat. Moreover, its underlying mechanism remains unknown. Considering that the dura mater is structurally the strongest and outermost membrane among the three-layered meninges, we hypothesized that a dural mechanical tear would trigger spontaneous cerebrospinal fluid leakage, especially when a traumatic loading event is involved. Thus, accurate biomechanical properties of the dura mater are indispensable for improving computational models, which aid in predicting blunt impact injuries and creating artificial substitutes for transplantation and surgical training. METHOD: We characterized the surface profile of the spinal dura and its mechanical properties (Young's moduli) with a distinction of its inherent anatomical sites (i.e., the cervical and lumbar regions as well as the dorsal and ventral sides of the spinal cord). FINDINGS: Although the obtained Young's moduli exhibited no considerable difference between the aforementioned anatomical sites, our results suggested that the wrinkles structurally formed along the longitudinal direction would relieve stress concentration on the dural surface under in vivo and supraphysiological conditions, enabling mechanical protection of the dural tissue from a blunt impact force that was externally applied to the spine. INTERPRETATION: This study provides fundamental data that can be used for accurately predicting cerebrospinal fluid leakage due to blunt impact trauma.

Brain herniation and subsequent complications following partial resection of high-grade glioma: A case report.

Key Clinical Message: This case highlights the need for tailored strategies to address issues like brain herniation, subdural hygroma, and cerebrospinal fluid leak, which, if not managed promptly, can lead to long-term neurological deficits. Additionally, the role of specialized facilities in delivering highly specialized care for managing such intricate cases cannot be understated. Abstract: Decompressive craniectomy-induced subdural hygroma (SDH) frequently coexists with external cerebral herniation, resulting in neurological impairments. The incidence of brain herniation through a craniectomy defect postoperatively is 25%. Brain herniation (BH), SDH, and cerebrospinal fluid leak require urgent neurosurgical management as they can lead to irreversible long-term neurological deficits. We report a case of a 42-year-old male who presented with headache and grand mal seizures. He was diagnosed with herniation of brain parenchyma through the surgical defect with a displacement of the bone flap by a heterogeneously enhancing lesion in the left parietal lobe along with SDH in the left frontoparietal region post partial resection of high-grade glioma. In this report, we discuss the pathogenesis and management strategies of brain herniation, wound infection, cerebrospinal fluid (CSF) leak, ipsilateral SDH, floating bone flap, and communicating hydrocephalus in an adult patient following partial resection of high-grade glioma. This particular case emphasizes the value of an individualized patient-centered surgical approach to minimize the risk of postoperative complications.

An unexpected complication of hypoglossal schwannoma surgery: Cerebrospinal fluid leakage-A case report and literature review.

BACKGROUND: Extracranial hypoglossal schwannoma is a rare tumor primarily treated with surgical excision. This article aims to highlight the potential for unexpected complications intraoperatively, such as cerebrospinal fluid leakage from skullbase to neck. METHODS: A previously healthy 23-year-old male presented with tongue numbness. Magnetic resonance imaging revealed a 17 × 20 mm nodular lesion adjacent to the cervical segment of the internal carotid artery. Surgical excision was scheduled due to suspicion of a neurogenic tumor. RESULTS: Intraoperatively, despite careful handling, cerebrospinal fluid leakage was observed. Manipulation of the mass caused detachment of proximal nerve fibers, potentially indicating avulsion of the hypoglossal nerve from the brainstem or nearby. Clear fluid leakage from the skull base was also noted. CONCLUSION: Thorough preoperative evaluation and patient education regarding potential complications are crucial. This article presents an unexpected complication encountered during surgical excision of extracranial hypoglossal schwannoma, emphasizing the need for awareness and preparedness in such cases.

Endoscopic endonasal repair of temporal lobe meningoencephalocele in the lateral recess of the sphenoid sinus, complicated by intracerebral hematoma: illustrative case.

BACKGROUND: Anomalies in the anatomical structure of the nasal cavity and paranasal sinuses often serve as a potential cause of spontaneous cerebrospinal fluid (CSF) leakage and may result in the development of a meningoencephalocele. In this report, the authors present a case of surgically treated intrasphenoidal meningoencephalocele attributed to the persistence of the lateral craniopharyngeal canal, which was further complicated by the occurrence of an intracerebral hematoma. OBSERVATIONS: A temporal lobe meningoencephalocele located in the lateral recess of the sphenoid sinus was successfully managed using endoscopic endonasal transpterygoid repair (EETR). However, an intracerebral hematoma developed after resection of the meningoencephalocele, necessitating additional surgical interventions. Despite this complication, the patient exhibited a favorable clinical outcome after the surgical interventions. LESSONS: This case highlights the potential risk of intracerebral hematoma associated with EETR of a lateral sphenoid sinus meningoencephalocele. A thorough examination of magnetic resonance imaging scans, especially identifying vascular structures, is crucial during surgical planning. This knowledge can help to prevent the occurrence of complications, including intracerebral hematoma.

Intraoperative cerebrospinal fluid leakage and residual tumors in endoscopic transsphenoidal surgery for pituitary adenoma: risk analysis and nomogram development.

BACKGROUND: Endoscopic transsphenoidal surgery is the primary method used to treat pituitary adenomas (PAs) at present; however, this technique is associated with certain risks, including cerebrospinal fluid leakage (CFL) and residual tumors (RTs). In this study, we aimed to identify specific risk factors for intraoperative CFL (ioCFL) and postoperative RT in patients with pituitary adenoma and construct a corresponding nomogram for risk assessment. METHODS: We collected a range of information from 782 patients who underwent endoscopic transsphenoidal PA resection in the Department of Neurosurgery at Beijing Tiantan Hospital between 2019 and 2021. Patients were then randomly assigned to training and validation groups (in a 8:2 ratio) with R software. Univariate and multivariable logistic regression models were then used to screen variables related to ioCFL and RT. These variables were then used to construct a predictive nomogram. Finally, the accuracy of the nomogram was validated by receiver operating characteristic curve (ROC) analysis, calibration plots, and decision curve analysis (DCA). RESULTS: Univariate and multivariable logistic regression models identified four risk factors for ioCFL (Hardy grade, tumor size, position, and consistency) and five risk factors for RT (operation time, tumor size, consistency, Knosp grade, and primary/recurrence type). The area under the ROC curve (AUC) for the ioCFL risk model was 0.666 and 0.697 for the training and validation groups, respectively. For RT, the AUCs for the two groups were 0.788 and 0.754, respectively. The calibration plots for the ioCFL and RT models showed high calibration quality and DCA analysis yielded excellent efficiency with regards to clinical decision making. CONCLUSION: Tumor size, growth characteristics, and invasion location were identified as the main factors affecting intraoperative CFL and RT. With our novel nomogram, surgeons can identify high-risk patients according to preoperative and intraoperative tumor performance and reduce the probability of complications.

Dural Reconstruction Materials for the Repairing of Spinal Neoplastic Cerebrospinal Fluid Leaks.

Spinal tumors often lead to more complex complications than other bone tumors. Nerve injuries, dura mater defect, and subsequent cerebrospinal fluid (CSF) leakage generally appear in spinal tumor surgeries and are followed by serious adverse outcomes such as infections and even death. The use of suitable dura mater replacements to achieve multifunctionality in fluid leakage plugging, preventing adhesions, and dural reconstruction is a promising therapeutic approach. Although there have been innovative endeavors to manage dura mater defects, only a handful of materials have realized the targeted multifunctionality. Here, we review recent advances in dura repair materials and techniques and discuss the relative merits in both preclinical and clinical trials as well as future therapeutic options. With these advances, spinal tumor patients with dura mater defects may be able to benefit from novel treatments.

Treatment of cerebrospinal fluid leakage with prolonged use of subfascial epidural drain and antibiotics in patients of thoracic myelopathy after posterior decompression surgery.

Background: Cerebrospinal fluid leakage (CSFL) is a prevalent and vexing complication associated with spine surgery. No standard protocol is available guiding CSFL management, especially for thoracic CSFL. The aim of this study was to retrospectively evaluate the efficacy of prolonged use of subfascial epidural drain and antibiotics to treat CSFL after posterior thoracic decompression surgery. Methods: Fifty-six patients with an average age of 52.3 years (24-76 years), who underwent thoracic decompression with CSFL (group A) and 65 patients with an average age of 54.9 years (25-80 years) without CSFL (group B) were retrospectively reviewed. Patients in group A had prolonged use of subfascial drainage and antibiotics and patients in group B were treated with conventional methods. The surgical results and rate of wound related complications was compared between the two groups. Results: The average subfascial drainage time was 7.0 ± 2.7 days (2-16 days) and 3.8 ± 1.4 days (2-7 days) in group A and B, respectively. Higher occupation rate (>49%), presence of dural ossification and higher MRI grade (>2) were more likely to presented with CSFL. In group A, four patients (7.1%) presented with deep wound infection and were successfully managed with wound debridement or intravenous antibiotics. In group B, one patient (1.5%) had a superficial wound infection and was treated with antibiotics. No patients presented with wound dehiscence, wound exudation or CSF fistulation. Conclusion: The occupation rate of ossified mass and presence of dural ossification were the major risk factors of CSFL. No significant difference in infection rates was observed between the patients in group A and B.

Spontaneous Intracranial Hypotension Occurring after Craniotomy for Brain Tumor Biopsy Mimicking Postoperative Bleeding.

In this study, we report on a previously healthy 44-year-old man who underwent an open biopsy under general anesthesia for a tumorous lesion found in his left frontal lobe via a small supratentorial craniotomy. While both postoperative course and brain computed tomography (CT) scans had been considered unremarkable, the patient became stuporous on postoperative day (POD) 4. A brain CT obtained on that day showed a subdural hematoma with marked brain shift which we thought might have been due to postoperative bleeding; he was immediately brought to an operating theater for hematoma removal. However, no bleeding source was found, and the brain remained depressed after hematoma evacuation. Furthermore, the brain shift remained unchanged on postoperative CT. While spontaneous intracranial hypotension (SIH) was considered, imaging studies to search for possible cerebrospinal fluid (CSF) leakage in the spinal column were not performed as the patient's condition has improved. However, he became stuporous again on POD 8, which urged us to perform CT myelogram. The CT myelogram showed a massive CSF leakage at the L1-L2 level. Subsequent autologous blood patch has successfully terminated the CSF leakage, and he became fully oriented shortly after the blood patch therapy. Thus, it should be noted that SIH may occur during postoperative period of intracranial surgery, and it may manifest radiographically as a subdural hematoma indistinguishable from postoperative bleeding. SIH should also be included in a differential diagnosis of postoperative headache, regardless of its characteristics, because headache associated with SIH may not always be orthostatic.

Cut-off value for ß-trace protein (ß-TP) as a rapid diagnostic of cerebrospinal fluid (CSF) leak detection.

Objective: To find an adequate cut-off point for beta trace protein (ß-TP) in nasal secretion (NS) and validate this diagnostic test with a large sample of patients. Likewise, we evaluated ß-TP test efficacy to confirm the cerebrospinal fluid (CSF) leakage closure after treatment. Methods: We performed a retrospective analysis with 207 samples from 162 patients with suspected CSF leakage received in the Hospital Universitario Virgen de la Arrixaca between 2010 and 2016. Twenty-five samples were included in the control group. Samples were obtained from NS through a swab to determine ß-TP using a nephelometry-based assay. Sensitivity, specificity, and area under the curve (AUC) for ß-TP in NS were assessed using the receiver operator characteristic (ROC) analysis. Results: Using imaging techniques, the diagnosis of CSF leak was confirmed in 57 patients (35.19%), while 105 had a negative diagnosis (64.81%). Patients with CSF leakage had significantly higher ß-TP values in NS (16.07 ± 16.94 mg/L, p < .001) than the control group (0.33 ± 0.12 mg/L) and patients without CSF leakage (0.61 ± 2.34 mg/L). Applying a 1 mg/L cut-off point resulted in 96.5% sensitivity and 97.1% specificity. Positive and negative predictive values (PPV and NPV) at this cut-off were 94.9% and 98.6%, respectively. Finally, this cut-off point yields a test efficacy for CSF leak diagnosis of 97% (95% CI 92.9-98.9). Conclusion: Our study has established a 1 mg/L ß-TP concentration in NS as a cut-off point for CSF leakage diagnosis with high sensibility and specificity. These results suggest that ß-TP analysis could be useful to check CSF leak resolution. Level of Evidence: 4.

Postoperative Serum C-Reactive Protein and Cerebrospinal Fluid Leakage after Endoscopic Transsphenoidal Surgery.

Objective Postoperative cerebrospinal fluid (CSF) leakage in endoscopic transsphenoidal surgery is a potential risk that requires immediate repair. We investigated the potential of common postoperative hematological examinations for diagnosing postoperative CSF leakage. Methods We retrospectively studied 214 consecutive cases who underwent endoscopic transsphenoidal approach (ETSA; transsellar approach) or extended ETSA (E-ETSA). Patients with postoperative CSF leakage were defined the leak group (group L), and patients without were defined as the nonleak group (group N). Postoperative C-reactive protein (CRP) was compared between the ETSA and E-ETSA groups, and between the N and L groups. Results The values of white blood cell count and CRP 1 to 7 days after surgery were significantly higher in the L group. Especially, CRP was clearly elevated in the L group ( p < 0.001). The CRP value was higher in patients in the N group after E-ETSA than after ETSA ( p < 0.001). CRP increased on the day after surgery but decreased gradually thereafter in patients after ETSA and in the N group. In contrast, CRP value tended to increase gradually after surgery in the L group. In particular, the CRP on the day before the CSF leak was confirmed was clearly higher than on the fifth to seventh days in the N group. Conclusion Elevated CRP after endoscopic endonasal transsphenoidal surgery is a potential marker of CSF leakage.