A Customized Technique of Cranioplasty for Patients with Large Skull Defects: A Technical Note.

OBJECTIVE: In our technical note, we have presented a technique of cranioplasty for large skull defects. METHODS: A thin-slice computed tomography scan is performed. A model of the skull is constructed using a desktop 3-dimensional printer from the computed tomography scan. The skull model is filled with towels of soft cotton and inserted in a sterile thin plastic bag. The implant is molded intraoperatively on the skull model under sterile conditions. After surgical exposure of the skull defect, the implant is inserted and fixed using miniplates and miniscrews. The technique was used in 6 patients and described in 2 representative cases. RESULTS: The required time and cost are significantly lower than those for other techniques used for preoperative manufacture of implants. No technique-related complications occurred. The radiological and cosmetic results were satisfactory. In the present case series, no early or delayed complications occurred. CONCLUSION: The presented technique is simple, safe, and time- and cost-effective. The technique and results are reproducible.

Changes in Intranetwork Functional Connectivity of Resting State Networks Between Sessions Under Anesthesia in Neurosurgical Patients.

BACKGROUND: In this study, we evaluated the changes in resting-state networks (RSNs) under anesthesia in neurosurgical patients. METHODS: RSNs were analyzed in 12 patients with pituitary adenoma presented by chiasma compression operated via standard transsphenoidal approach under propofol anesthesia before and after tumor resection. All the patients had suprasellar tumor extension with compression of the optic chiasma. We investigated second-level effects by contrasting dummy-encoded covariates representing the effects of the sessions (first vs. second) on RSNs. We corrected for multiple comparisons using a false discovery rate of 0.05 (2-sided). RESULTS: Connectivity between the right and left precentral gyri (motor network) decreased significantly from the first to the second session (P = 0.0002), as did the connectivity between the postcentral gyri (P = 0.009). The same was valid for connectivity between the visual cortices (P = 0.0002). The salience network showed a significant decrease in the connectivity of the anterior part of the cingulate gyrus and insular cortex (P = 0.0001). The default mode network showed a decrease in the connectivity between the posterior part of the cingulate gyrus, parietal, and frontal cortices (P = 0.0002). There was no significant correlation between the reduction in connectivity and dose or duration of anesthesia. CONCLUSIONS: Different RSNs could be identified under anesthesia and used for intraoperative brain mapping and remapping during tumor resection. However, RSNs showed a significant decrease in connectivity with the continuation of anesthesia.

Data-Driven Identification of the Regions of Interest for Fiber Tracking in Patients with Brain Tumors.

BACKGROUND: We investigated the added value of combining information from direction-encoded color (DEC) maps with high-resolution structural magnetic resonance imaging scans (T1-weighted images [T1WIs]) to improve the identification of regions of interest (ROIs) for fiber tracking during preoperative planning for patients with brain tumors. METHODS: The dataset included 42 patients with gliomas and 10 healthy subjects from the Human Connectome Project. For identification of the ROIs, we combined the structural information from high-resolution T1WIs and the directional information from DEC maps. To test our hypothesis, we examined the interrater and intrarater agreement. RESULTS: We identified specific ROIs to extract the main white matter bundles. The directional information from the DEC maps combined with the T1WIs (T1WI-DEC maps) had significantly facilitated ROI identification in patients with brain tumors, especially patients in whom the tracts had been displaced by the mass effect of the tumor. Fiber tracking using the combined T1WI-DEC maps showed significantly greater inter- and intrarater agreement compared with using either T1WI or DEC maps alone. CONCLUSION: Combining the information from diffusion-derived color-encoded maps with high-resolution anatomical details from structural imaging (T1WI-DEC map), especially in patients with brain tumors, could be useful for accurate identification of the ROIs.

The Fluctuations of Blood Oxygen Level-Dependent Signals as a Method of Brain Tumor Characterization: A Preliminary Report.

OBJECTIVE: In this study we present the nature and characteristic of the fluctuation of blood oxygen level-dependent (BOLD) signals measured from brain tumors. METHODS: Supratentorial astrocytomas, which were neither operated nor previously managed with chemotherapy or radiotherapy, were segmented, and the time series of the BOLD signal fluctuations were extracted. The mean (across patients) power spectra were plotted for the different World Health Organization tumor grades. One-way analysis of variance (ANOVA) was performed to identify significant differences between the power spectra of different tumor grades. Results were considered significant at P < 0.05. RESULTS: A total of 58 patients were included in the study. This group of patients included 1 patient with grade I glioma; 15 with grade II; 12 with grade III; and 30 with grade IV. The power spectra of the tumor time series were individually inspected, and all tumors exhibited high peaks at the lower frequency signals, but these were more pronounced in high-grade tumors. ANOVA showed a significant difference in power spectra between groups (P = 0.000). Post hoc analysis with Bonferroni correction showed a significant difference between grade II and grade III (P = 0.012) and grade IV (P = 0.000). There was no significant power spectra difference between grade III and IV tumors (P = 1). CONCLUSIONS: The power spectra of BOLD signals from tumor tissue showed fluctuations in the low-frequency signals and were significantly correlated with tumor grade. These signals could have a misleading effect when analyzing resting state functional magnetic resonance imaging and could be also viewed as a potential method of tumor characterization.

Inter-Network Functional Connectivity Changes in Patients With Brain Tumors: A Resting-State Functional Magnetic Resonance Imaging Study.

OBJECTIVE: Measuring functional connectivity (FC) and resting state networks (RSNs) using resting state functional magnetic resonance imaging is a method of preoperative planning in patients with brain tumors. However, the baseline FC and RSNs are altered in patients with brain tumors. In this study, we examined changes in inter-network FC in patients with brain tumors. METHODS: We performed region of interest (ROI) analysis of FC in 34 patients with supratentorial gliomas and 14 healthy subjects. We performed bivariate correlation analyses at the level of each subject. Resulting correlations were Fischer Z-transformed. The used nodes included 132 ROIs from the automated anatomical labeling atlas in addition to 32 ROIs representing the different functional brain networks. We investigated second-level effects by contrasting dummy encoded covariates representing the effects of group membership on functional connectivity. The significant 2-sided P value with corrected false discovery rate was set to 0.05. We set the t contrast between the group of patients with brain tumors and the group of healthy subjects to detect the effects of tumors on inter-network connectivity. RESULTS: Overall, the inter-network FC was significantly higher in patients with brain tumors compared with healthy subjects. The anterior and posterior cerebellar networks, as well as the supratentorial network, showed significantly higher connectivity in patients with brain tumors than in healthy subjects. CONCLUSION: Although brain tumors affect the FC and RSNs, the current study showed higher baseline inter-network connectivity in patients with brain tumors, which could indicate an intrinsic neural compensatory mechanism.

Intraoperative Resting-State Functional Connectivity and Resting-State Networks in Patients with Intracerebral Lesions: Detectability and Variations Between Sessions.

OBJECTIVE: To evaluate the functional connectivity (FC) and resting-state networks (RSNs) in patients under anesthesia operated for resection of intracerebral lesions. METHODS: We performed intraoperative resting-state functional magnetic resonance imaging (irs-fMRI) in 24 patients under anesthesia before and after lesion resection. Correlation matrices were established for each session (a total 48 of sessions). We analyzed the changes in overall FC and in FC of the healthy and operated hemispheres between the first and second sessions. We tested the correlation between changes in FC and clinical outcomes and the duration, rate, and total dosage of anesthesia. We also performed a group analysis to detect topographic changes in RSNs in patients under anesthesia. A single-subject analysis was performed to detect clinically relevant RSNs in each patient. RESULTS: FC decreased significantly in the second session, as did interhemispheric connectivity. The decrease in the pathological hemisphere was significant and significantly greater than the decrease in the intrahemispheric connectivity of the healthy hemisphere. The change in FC was not correlated with clinical outcome or with the duration, rate, or dosage of anesthesia. Group analysis showed topographic changes in RSNs, especially in high-level networks such as default mode and salience networks. Identification of clinically relevant networks was also possible. CONCLUSIONS: FC and RSNs could be identified under anesthesia and used for extended brain mapping. Further studies are needed to optimize the depth of hypnosis to stabilize FC between sessions.

Imaging features and classification of peritumoral edema in vestibular schwannoma.

BACKGROUND: Peritumoral edema (PTE) is rarely present in patients with vestibular schwannomas (VS). We studied the correlation between radiological tumor characteristics and the presence of edema, describe its magnetic resonance imaging features and classify the different edema patterns. METHODS: We analysed 605 consecutive patients treated for VS at our Institute. PTE was found in 30 patients, studied on fluid attenuated inversion recovery sequences and categorised as involving the brachium pontis, cerebellum and/or brainstem. Tumor volume, shape, surface, internal structure and axis of growth were evaluated and compared to a matched series of 30 patients without PTE. RESULTS: In our population of patients, 5% showed PTE. Edema involved the brachium pontis in 22 cases (88%), cerebellum in 15 (60%) and brainstem in 3 (12%). PTE was classified as mild (one region involved), moderate (two regions) and severe (three regions). Edema was present not only perpendicular to the major tumor growth axis but also parallel to it (91%). The difference between the two groups in regards to tumor shape and surface was not significant. We found no correlation between tumor and edema volumes. CONCLUSIONS: VS can cause PTE, but its incidence is less frequent than in skull base meningiomas. PTE involves most frequently the brachium pontis, followed by the cerebellum and brainstem. Its occurrence correlates with tumor size but not with other radiological VS features. PTE is not always located perpendicular to the major axis of tumor growth, which indicated that the compressive theory proposed for meningiomas is not plausible explanation for its manifestation.

Prognostic Significance of Preoperative Geometric Changes in the Internal Acoustic Canal for Hearing Preservation in Vestibular Schwannoma Surgery.

OBJECTIVE: This study focused on the changes in the internal acoustic canal (IAC) caused by vestibular schwannomas (VSs) and their prognostic significance for postoperative hearing outcome. METHODS: A total of 125 consecutive cases of VS were included. We used a neuronavigation software to perform the following measurements on both the tumor side and healthy side: volume of the IAC (VIAC), maximal diameter of the IAC (DIAC), and length of the IAC (LIAC). A statistical analysis was realized using Spearman correlation to test the correlation of the morphometric measure of the IAC and postoperative hearing. Multivariate analysis was performed to test the impact of measurements of the IAC and preoperative hearing on postoperative hearing. RESULTS: The mean VIAC on the tumor side and on the healthy side was 0.271 and 0.169 cm3, respectively. The mean DIAC was 9.438 mm on the tumor side and 7.034 mm contralateral. The correlations tests showed significant correlations of both postoperative hearing deficit and degree of hearing loss with 1) VIAC on the tumor side, 2) difference between VIAC on the tumor side and healthy side, 3) DIAC on the tumor side, and 4) difference between the DIAC on the tumor side and healthy side. The multivariate analysis showed significant impact of the DIAC (P = 0.01) and preoperative hearing status (P = 0.02) on postoperative hearing. CONCLUSIONS: Enlargement of the VIAC and DIAC are negative prognostic factors for hearing preservation. Reasons may be long-standing compression of the auditory nerve and an increased vulnerability of the inner ear structures during the drilling of the IAC.

Can Intraoperative Magnetic Resonance Imaging Be Helpful in the Surgical Resection of Parasellar Meningiomas? A Case Series.

OBJECTIVE: The surgery of parasellar meningiomas is crucial. There are only a few reports of the use of intraoperative magnetic resonance imaging (iMRI) for resection of these lesions. We discuss the safety and usefulness of this technique in achieving the planned surgical goal and analyze patients' outcomes. METHODS: Nineteen cases of parasellar meningioma were treated in our institution using iMRI. We classified the tumors according to their primary location: tuberculum sellae, clinoidal, and cavernous sinus meningiomas. We evaluated the history of previous surgery, outcome, residual (if present) tumor volume, degree of resection, achievement of the surgical goal, and number of iMRI scans. RESULTS: The preoperative surgical goal was achieved in all patients. In 7 of 19 patients, (37%) further tumor resection was performed after the first iMRI scan. Regarding the cavernous sinus group, the surgical resection was continued after the first iMRI in 56% of patients, obtaining substantial additional volume reduction. No complications were found related to the use of iMRI scan. CONCLUSIONS: iMRI has been effective in safely increasing the extent of parasellar meningioma resection mainly for recurrent and invasive tumors. Its usefulness has been seen mostly in cavernous sinus lesions, in which it allowed the further safe resection in 56% of cases. Moreover, this tool was particularly useful in recurrent or residual meningiomas with extension in extracranial compartments.

Seed-Based Connectivity Analysis of Resting-State fMRI in Patients with Brain Tumors: A Feasibility Study.

OBJECTIVE: In this study, we present our experience using resting-state functional magnetic resonance imaging (rs-fMRI) in preoperative planning. We performed group analysis to demonstrate the effects of brain tumor on resting-state networks (RSNs). METHODS: Thirty patients with supratentorial gliomas were included in the study. Preoperative rs-fMRI and structural magnetic resonance imaging were performed in all cases. The rs-fMRI was preprocessed (realignment, slice time correction, coregistration to structural images, normalization, and smoothing). The structural images were segmented and normalized. Band filtering and denoising were applied to the functional images. Connectivity analysis was performed using seed-based connectivity analysis (SCA) at single subject level and group level. Correlation algorism has been used with r > 0.5. RESULTS: RSNs could be detected in all patients. They showed similarity to the results of the task-based fMRI, when task-based fMRI was feasible. Detection of the networks was also possible in patients with neurologic deficits, in whom task-based fMRI was not possible. We could use SCA in patients under anesthesia. High-level networks (default mode, salience, and dorsal attention networks) were detectable but showed a wide spectrum of spatial alterations and component disconnections. CONCLUSIONS: rs-fMRI is a feasible method for extended brain mapping. Diverse RSNs could be detected in patients with brain tumors and could be applied in preoperative planning. SCA was a robust and direct approach for data analysis and could answer specific clinically relevant questions. However, further studies are needed to validate the technique and its clinical impact.

The Significance of Intraoperative Magnetic Resonance Imaging in Resection of Skull Base Chordomas.

BACKGROUND: Skull base chordoma can be a challenging surgical entity because of its invasive nature. OBJECTIVE: In this study, the role of intraoperative magnetic resonance imaging (iMRI) to optimize the resection of skull base chordomas is evaluated. METHODS: We performed a retrospective analysis of operated patients with skull base chordomas in the setting of iMRI. The clinical records, operative notes, radiologic images, tumor volumetry, location of the residual tumor, and surgical outcome were evaluated. RESULTS: Fifteen patients were operated on for resection of skull base chordomas between 2010 and 2017 in our institution. Gross total resection was planned and achieved in 8 patients and partial resection in 7 patients. In 8 patients (53.3%), the preoperatively planned volume of resection was achieved and confirmed in the first iMRI control. In 7 patients, repeated iMRI controls were required to achieve the surgical target. In 3 patients, the tumor residual requiring further resection was located in the clivus and in 4 patients in the intradural space. The improvement of the preoperative deficits showed a significant statistical association with the resection of the intradural component and decompression of the brainstem. CONCLUSIONS: This study shows that iMRI is a safe method for intraoperative assessment of the degree of resection and the volume and location of residual tumor when resecting skull base chordomas. When gross total resection of the tumor is not feasible, iMRI can be a useful tool for targeted tumor resection.

Reliability of Functional Magnetic Resonance Imaging in Patients with Brain Tumors: A Critical Review and Meta-Analysis.

BACKGROUND: Formal studies that validated functional magnetic resonance imaging (fMRI) against direct cortical stimulation (DCS) have shown inconsistencies. METHODS: We reviewed the reported data and performed a meta-analysis of studies that had validated fMRI using DCS and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We performed the meta-analysis of the studies that had met our inclusion criteria. The positive predictive values (PPVs), negative predictive values (NPVs), false omission rates (FORs), false discovery rates (FDRs), sensitivity, and specificity were calculated. We also identified the factors that could influence the fMRI findings. RESULTS: Six studies of language activation and two of motor activation were eligible for the present meta-analysis. The PPV of fMRI for the detection of eloquent motor cortex was 59.5%, and the FDR was 40.5%. The NPV was 96% and the FOR was 3.9%. The sensitivity and specificity of fMRI for the detection of the eloquent motor cortex was 91% and 76%, respectively. For language activation, the PPV was 71.7%, the NPV was 80%, the FDR was 28.2%, and the FOR was 19.5%. The sensitivity and specificity was 80% and 71.5%, respectively. The factors that could have caused a mismatch or affected the reliability were analyzed. CONCLUSION: The results from the present analysis of the available reported evidence suggest that fMRI itself (due to neurovascular uncoupling) or analysis of the findings have limitations regarding reliability when validated against DCS. From the existing studies, our results indicate that using fMRI alone for surgical planning could lead to undesirable outcomes.

Resting-State Functional Connectivity in Neurosurgical Patients Under Propofol Anesthesia: Detectability and Variability Between Patients and Between Sessions.

BACKGROUND: Intraoperative assessment of functional connectivity (FC) provides a new possibility for mapping the eloquent brain region before, during, and after tumor resection. The aim of this study was to perform a systematic analysis of detectability of FC and its variation between subjects and sessions. METHODS: FC was analyzed in 10 patients with pituitary adenoma under propofol anesthesia before and after tumor resection. FC of each session (20 sessions total) was correlated to a reference matrix of a group of healthy subjects to evaluate variations of overall, interhemispheric, and intrahemispheric FC between sessions. RESULTS: Resting-state patterns could be detected during anesthesia (F1,9 = 112.14, P < 0.001). There was a significant effect of session (F1,9 = 19.401, P = 0.002), which included a reduction in resting state from the first to second session. There was no effect of connection type (F2,8 = 1.498, P = 0.280), and there was no interaction between connection type and session (F2,8 = 0.187, P = 0.833). The correlation between the observed reduction in resting-state activity between the sessions and the time span between sessions was not significant (r = 0.25, P = 0.29). FC of the first session showed a significant correlation to the initial dose of anesthesia (r = 0.7, P = 0.007). However, there was no significant correlation between the total dose of propofol and FC of the second session (r = 1.7, P = 0.6). CONCLUSIONS: Significant FC could be detected under anesthesia but showed a significant decrease in the second session. To implement FC intraoperative brain mapping, further studies are required to optimize the depth sedation to obtain stable FC between sessions.

Nervus intermedius dysfunctions after vestibular schwannoma surgery: a prospective clinical study.

OBJECTIVE: The purpose of this prospective study was to evaluate the dysfunction of the nervus intermedius (NI) after vestibular schwannoma (VS) surgery. The authors present a clinically feasible method for this purpose. METHODS: In this prospective study, the authors included 30 patients who underwent surgery at the International Neuroscience Institute between May 2014 and February 2017 for resection of VS. The patients' taste sensation was examined using taste strips. Lacrimation was tested using the Schirmer I test. The clinical evaluation was performed before surgery and repeated at 2 weeks and at 6 months after surgery as well as during the follow-up, which extended up to 2 years. The authors tested the correlation between the NI dysfunctions and the House-Brackmann grade of facial nerve palsy. RESULTS: The taste sensation was lost on the side of surgery in 2 patients (6.6%) and decreased in 4 patients (13.3%). The disturbance of taste sensation was not statistically correlated with dysfunctions of the motor portion of the facial nerve. The taste impairment resolved in 4 patients within 6 months, but 2 patients suffered from persistent loss of the taste sensation on the side of surgery during the follow-up. In 23 patients (76.6%), the baseline lacrimation was lower on the side of surgery, and it was significantly correlated with outcome for dysfunctions of the motor portion of the facial nerve. During the follow-up, baseline lacrimation improved in correlation with the improvement in the dysfunctions of the motor portion of the facial nerve. None of the patients reported change in salivation or nasal secretion. CONCLUSIONS: The NI can be affected after VS surgery. The disturbance of baseline lacrimal secretion was correlated with dysfunctions of the motor portion of the facial nerve. However, the disturbance of the taste sensation was not correlated with the grade of facial nerve palsy. Dysfunctions of the NI should be evaluated and separately reported while analyzing facial nerve outcome after VS surgery.

Efficiency and Safety of Autologous Fat Grafts in Reconstructing Skull Base Defects After Resection of Skull Base Meningiomas.

BACKGROUND: Reconstruction of the skull base after resection of skull base meningiomas is of paramount importance. Here we describe a safe and effective method of skull base reconstruction using autologous free fat grafts. METHODS: In this retrospective analysis of patients operated for skull base meningioma from 2007 to 2014. We analyzed the surgical technique, efficiency and safety as well as the graft-related complications. RESULTS: Autologous free fat grafts were used in 55 patients, including 39 patients with posterior fossa meningiomas related to the petrous bone and 16 patients with anterior fossa meningiomas related to the paranasal sinuses. Three patients experienced postoperative cerebrospinal fluid (CSF) leak and were managed with temporary continuous lumbar drainage. One patient developed pneumocephalus and required revision. The occurrence of CSF leak was related to aggressive resection with resulting large skull base defects, especially in anterior skull base meningiomas. There were no donor site-related complications. CONCLUSIONS: The use of autologous free fat grafts is an effective and safe technique for reconstructing skull base defects after microsurgical resection of skull base meningiomas.

Prognostic significance of intraoperative change in the fractional anisotropy and the volume of the optic chiasma during resection of suprasellar tumors.

OBJECTIVE The aim of this study was to test the prognostic significance of intraoperative changes in the fractional anisotropy (FA) and the volume of the optic chiasma and their correlation with visual outcome. METHODS Twenty-eight sequential patients with suprasellar tumors presenting with chiasma compression syndrome were surgically treated under intraoperative MRI control between March 2014 and July 2016. The FA and the volume of the optic chiasma were measured immediately before and immediately after tumor resection. The visual impairment score (VIS) was used to quantify the severity of the ophthalmological disturbances before surgery, 10-14 days after surgery, and again 3 months thereafter. The change in the FA and the volume of the optic chiasma was correlated to the improvement of vision. The correlation between other predictors such as the age of the patients and the duration of symptoms and the visual outcome was tested. RESULTS The VIS improved significantly after surgery. The FA values of the optic chiasma decreased significantly after decompression, whereas the volume of the optic chiasma increased significantly after decompression. The early and delayed improvement of vision was strongly correlated to the decrease in the average FA and the increase of the volume of the optic chiasma. The duration of symptoms showed a significant negative correlation to the visual outcome. However, the decrease in the FA showed the strongest correlation to the improvement of the VIS, followed by the expansion of the optic chiasma, and then the duration of symptoms. CONCLUSIONS The decrease in the FA and the expansion of the optic chiasma after its decompression are strong early predictors of the visual outcome. These parameters are also able to predict delayed improvement of vision.

Intraoperative Monitoring of the Integrity of the Anterior Visual Pathways: A Methodologic Review and Meta-Analysis.

BACKGROUND: Diverse methods have been developed for intraoperative monitoring of the integrity of the visual pathways. We performed a review of the literature to determine the methodology of each technique as well as their recent development. The predictive power of each eligible technique was determined based on a meta-analysis. METHODS: A literature review was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Techniques adopted for intraoperative monitoring of the integrity of the visual pathways were extracted and described. The power of each eligible technique to predict the visual outcome was tested. RESULTS: Visual evoked potentials showed marked methodologic improvement in recent studies. Predictive power for visual deterioration after surgery was approximately 60% and reached 100% when coupled with simultaneous monitoring of electroretinography. The sensitivity of visual evoked potentials for detection of deterioration was 47.2%. The decrease of fractional anisotropy of the optic chiasma showed significant correlation with improvement of vision after chiasma compression and showed 100% predictive power for improvement. CONCLUSION: Each technique had limitations. Visual evoked potentials had a high predictive power for detection of deterioration but with low sensitivity. Fractional anisotropy of the optic chiasma had high predictive power for improvement of vision with low predictive power for deterioration.

Transcranial Evacuation of Atypical Progressive Supradiaphragmatic Hematoma After Transsphenoidal Complete Resection of Pituitary Adenoma.

OBJECTIVE: Supradiaphragmatic hematoma is a type of hematoma that occurs after transsphenoidal (TS) resection of pituitary adenoma and requires special management. METHODS: Two patients had symptomatic supradiaphragmatic hematomas after total TS resection of pituitary adenomas in the absence of vascular anomalies. Both patients also had hydrocephalus at the time of diagnosis of the hematoma. The initial endoscopic endonasal inspection showed no subdiaphragmatic bleeding. The hematoma was evacuated via a frontolateral approach after insertion of an external ventricular drain (EVD). RESULTS: The supradiaphragmatic hematoma could be clinically and radiologically distinguished. It presented early with visual deterioration without headache. The patients developed hydrocephalus, which was associated with deterioration of level of consciousness. Radiologically, the hematoma filled the suprasellar space and was associated with the extension of bleeding in the basal cisterns. Recovery was good in both patients. There were no permanent neurologic deficits. The EVD was removed in both patients. One patient required a ventriculoperitoneal shunt because of delayed hydrocephalus. CONCLUSIONS: Supradiaphragmatic hematoma can be clinically and radiologically distinguished from other types of hematoma occurring after TS resection of pituitary adenoma. Transcranial surgery should be performed to manage supradiaphragmatic hematoma, when symptomatic. Insertion of an EVD at the time of evacuation is mandatory to relax the brain and to alleviate the hydrocephalus.

Efficacy of microsurgical tumor removal for treatment of patients with intracanalicular vestibular schwannoma presenting with disabling vestibular symptoms.

OBJECTIVE The aim of this study was to analyze the efficacy and risks of microsurgery via the hearing-preserving retrosigmoid approach in patients with intracanalicular vestibular schwannoma (VS) suffering from disabling vestibular symptoms, with special attention to vertigo. METHODS This is a retrospective analysis of 19 patients with intracanalicular VS and disabling vestibular dysfunction as the main or only symptom (Group A). All of the patients reported having had disabling vertigo attacks. Subjective evaluation of the impairment of patients was performed before surgery, 3 weeks after surgery, 3 months after surgery, and 1 year after surgery, using the Dizziness Handicap Inventory (DHI). The main outcome measures were improvement in quality of life as measured using the DHI, and general and functional outcomes, in particular facial function and hearing. Patient age, preoperative tumor size, preoperative DHI score, and preservation of the nontumorous vestibular nerve were tested using a multivariate regression analysis to determine factors affecting the postoperative DHI score. The Mann-Whitney U-test was used to compare the postoperative DHI score at 3 weeks, 3 months, and 1 year after surgery with a control group of 19 randomly selected patients with intracanalicular VSs, who presented without vestibular symptoms (Group B). The occurrence of early postoperative discrete vertigo attacks was also compared between groups. RESULTS The preoperative DHI score was ≥ 54 in all patients. All patients reported having had disabling rotational vertigo before surgery. The only significant factor to affect the DHI outcome 3 weeks and 3 months after surgery was the preoperative DHI score. The DHI outcome after 1 year was not affected by the preoperative DHI score. Compared with the control group, the DHI score at 3 weeks and 3 months after surgery was significantly worse. There was no significant difference between the groups after 1 year. Vertigo was improved in all patients and completely resolved after 1 year in 17 patients. CONCLUSIONS Disabling vestibular dysfunction that affects quality of life should be considered an indication for surgery, even in otherwise asymptomatic patients with intracanalicular VS. Surgical removal of the tumor is safe and very effective in regard to symptom relief. All patients had excellent facial nerve function within 1 year after surgery, with a very good chance of hearing preservation.