"Curtain-fall" technique for cerebrospinal fluid leak prevention after removal of intradural drainage. Technical note: application in chronic subdural hematoma surgery.

OBJECTIVE: Chronic subdural hematoma (CSDH) is frequently met in neurosurgical practice and often need urgent surgical treatment in case of neurological deterioration. Different surgical approaches to evacuate CSDH are described in the literature. In our experience, an external drainage system is crucial in order to avoid recurrences. We recently encountered a case of subcutaneous CSF collection after drainage removal. Thus, we developed a simple surgical technique to prevent postoperative CSF leak after subdural drainage system removal. METHOD: We have developed a technique in which the periosteum is harvested during the surgery prior to the evacuation of the hemorrhage and fixed with sutures on the uncut dura mater opposite and laterally to the exit of the catheter exiting the dural hole caused by the passage of the Jackson-Pratt subdural drainage system. When the drainage catheter is removed, the flap, partially held by the sutures, falls over the hole avoiding CSF leakage. By using this technique, the small dural hole will be covered with the periosteum allowing for natural closure and wound healing hence preventing CSF leakage. RESULTS: This technique was successfully employed in 21 patients who didn't develop postoperative CSF leakage following CSDH evacuation and removal of subdural drainage system. CONCLUSION: In this technical note, we describe a safe dura closure technique that we developed to help reduce the risk of postoperative CSF leakage following subdural drainage removal, which can, however, also be applied in all surgeries in which a catheter is placed in the subdural space.

Craniotomy tools: description of a test model for the evaluation of craniotome blade efficiency.

Craniotomes have shown to be fast and precise in performing bone flaps. Nevertheless, in everyday practice, the neurosurgeon can experience breakage of the blade and other complications like dural tears during cutting of the bone. We developed a test procedure for craniotomies and used it to compare two blade types. We used bovine scapulae to perform three tests. Five testers carried out every trial. Test 1: a 4-cm straight line was performed with both blades. Test 2: each tester performed a spiral cut. Test 3: a zig-zag cut with angles of 90° was performed by all testers with both blade types. The mean time needed to achieve the 4-cm cut in test 1 was 29.50 and 17.88 s, respectively, for the previous and new blade. In test 2, the calculated mean speed (cm/s) was 0.138 using the previous blade model and 0.178 using the new one. In test 3, the mean number of 90° angles per second performed with both blades is comparable with values of 0.058 and 0.063, respectively, for the previous and new blade. The variable considered: speed of cutting and resistance to breakage shows that the novel blade is faster in performing all the three types of cut and has higher compliance with stress.

Torkildsen's Ventriculocisternostomy First Applications: The Anthropological Evidence of a Young Slavic Soldier Who Died in the Torre Tresca Concentration Camp (Bari, Italy) in 1946.

Human skeletal remains are considered as real biological archives of each subject's life. Generally, traumas, wounds, surgical interventions, and many human pathologies suffered in life leave identifiable marks on the skeleton, and their correct interpretation is possible only through a meticulous anthropological investigation of skeletal remains. The study here presented concerns the analysis of a young Slavic soldier's skeleton who died, after his imprisonment, in the concentration camp of Torre Tresca (Bari, Italy), during the Second World War (1946). In particular, the skull exhibited signs of surgical activity on the posterior cranial fossa and the parieto-occipital bones. They could be attributed to surgical procedures performed at different times, showing various degrees of bone edge remodeling. Overall, it was possible to correlate the surgical outcomes highlighted on the skull to the Torkildsen's ventriculocisternostomy (VCS), the first clinically successful shunt for cerebrospinal fluid (CSF) diversion in hydrocephalus, which gained widespread use in the 1940s. For this reason, the skeleton we examined represents a rare, precious, and historical testimony of an emerging and revolutionary neurosurgical technique, which differed from other operations for treating hydrocephalus before the Second World War and was internationally recognized as an efficient procedure before the introduction of extracranial shunts.

Transsphenoidal approach in children with partially or minimally developed sphenoid sinus.

OBJECT: The transsphenoidal approach is guided by a few fundamental anatomic landmarks. Pneumatization of the SS is variable, and this plays a key role in accessing the sella floor and other skull base structures. It may be absent or minimally present in both adult and, often, pediatric population, making surgical approach more difficult than usual. We aim to demonstrate that also in the more difficult cases, with a minimal level of pneumatization, the transsphenoidal approach is still possible especially with the support of neuronavigation and intraoperative magnetic resonance imaging (iMRI). METHODS: We present our experience accumulated after the treatment of 6 children with minimally pneumatized sphenoid sinus describing the workflow to access the sella floor. RESULTS: No perioperative complications due to the surgical approach were observed, and no cases of mortality were reported. After the surgery, the visual field deficit improved in 1 patient and remained stable in three patients. No postoperative new neurologic deficits were found. No cases of cerebrospinal fluid (CSF) leak were observed. CONCLUSIONS: The transsphenoidal approach can be safely used even in cases of minimally or even absent pneumatization of SS as in young children. In order to have a safe approach in such patients, the use of tools, such as navigation system and iMRI, is recommended. Furthermore, the iMRI allows to avoid exposure to radiation as in case of fluoroscopy.

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.

Use of Frameless Stereotactic Navigation System Combined with Intraoperative Magnetic Resonance Imaging and 5-Aminolevulinic Acid.

OBJECTIVE: We have described the integrated use of a neuronavigation-guided system for frameless stereotaxy (VarioGuide [Brainlab AG, Munich, Germany]) with intraoperative magnetic resonance imaging (iMRI) and 5-aminolevulinic acid (5-ALA) and report the advantages and disadvantages that the use of these tools together can have in the treatment of various types of intracerebral lesions. METHODS: After the skin incision, creation of a burr hole at the entry point, and dura opening, the VarioGuide procedure was started. Initially, the wizard software will require positioning of the stereotactic arm over the burr hole and provides feedback regarding the correct position. The procedure is performed in an iMRI theater furnished with a surgical microscope (Kinevo [Carl Zeiss AG, Oberkochen, Germany]) supplied with a violet-blue excitation light for 5-ALA fluorescence. At the end of the surgery, iMRI was performed. We present 2 exemplary cases to describe the application and workflow of these tools. RESULTS: When used for traditional biopsy, the possibility of performing a new iMRI scan could be of paramount importance because the brain shift can be compensated for and an alternative trajectory can be calculated from the new images and fiber tracking reconstruction. The fluorescence of the tissue sample examined under the microscope filter can provide immediate information about the nature of the lesion, allowing for the possibility of converting the procedure to open craniotomy and tumor removal. CONCLUSION: The use of combination frameless stereotaxy with iMRI and 5-ALA has shown benefits in terms of safety and precision. Moreover, the use of these tools can simplify tumor removal after simple biopsy, widening the spectrum of indications.

Endoscope-Assisted Microneurosurgery for Intracranial Aneurysms: Operative Technique, Reliability, and Feasibility Based on 14 Years of Personal Experience.

Endoscope-assisted microneurosurgery (EAM) combines endoscopic and microsurgical techniques for the treatment of deeply located intracranial lesions. During aneurysm surgery, endoscopic assistance may aid in the visualization of perforating arteries, especially when minimally invasive approaches are used. Between 2002 and 2015, a total of 183 patients with 208 intracranial aneurysms were surgically treated in our department. EAM was performed in 191 procedures. In all, 159 aneurysms were located in the anterior circulation and 49 in the posterior circulation. Of these, 135 aneurysms were ruptured. Lesions were exposed through standard skull base microsurgical approaches. The endoscope was employed during three steps: initial inspection, true operative time, and final inspection. Complications directly related to endoscopic procedures were rare; no surgical mortality was observed in this series. A retrospective analysis of each procedure showed that the usefulness of EAM depended on the anatomical location and size of the lesions. Its advantages were especially evident when dedicated scopes and holders were used.

Giant and Very Large Intracranial Aneurysms: Surgical Strategies and Special Issues.

Giant intracranial aneurysms (GIAs) and very large intracranial aneurysms (VLAs) have a poor natural history because of a high incidence of bleeding and strokes. These lesions always represent a great challenge for neurosurgeons and interventional neuroradiologists because of some peculiar intrinsic features such as size, angioarchitecture, wide neck, mass effect, intraluminal thrombosis, atherosclerotic changes, involvement of branches and perforators, and a frequent need to perform revascularization procedures. The results of a cumulative surgical series of 75 VLAs and GIAs are reported. Thirty-three aneurysms were unruptured. Sixty aneurysms underwent direct surgical treatment consisting of 56 direct clippings, 3 trappings w/o revascularization, and 1 wrapping. Fifteen aneurysms were treated by means of extracranial to intracranial (EC-IC) high-flow bypass. An mRS score ranging between 0 and 2 was observed in 54 patients, whereas an mRS of 3 was seen in 5 patients. Four patients had a severe disability (mRS 4-5) and six patients died. Aneurysm's fragmentation, with stacking and seating clips, thrombectomy, and aneurysmorrhaphy were the techniques most frequently employed. Revascularization options involving EC-IC high-flow bypass were used in cases not amenable for direct treatment. Some technical tips and special issues related to the surgical management of these complex lesions are discussed.

Surgical Treatment of Arteriovenous Malformations: Role of Preoperative Staged Embolization.

Preoperative embolization is complementary to surgery for large brain arteriovenous malformations (AVMs). From January 2005 to December 2015, 69 patients harboring an AVM were managed in our department by the same surgeon (RG). Forty one were ruptured and 65 were supratentorial. Thirty nine smaller AVMs were treated with surgery stand-alone, whereas, for 30 larger malformations, surgery was combined with adjuvant treatment involving preoperative staged embolization and/or, less frequently, radiosurgery. In all patients treated with surgery alone, complete resection of AVM was achieved. A successful preoperative partial endovascular obliteration of AVM was obtained in 24 out of 27 more complex cases, with a zero mortality rate and a very low morbidity. Here, embolization was of a certain utility in the handling of deeper feeders and nidus excision, also facilitating intraoperative hemostasis. In three cases of residuals, radiosurgery was performed. In those patient treated with a combined approach, a good overall outcome, 0-2 modified Rankin Scale (mRS), was achieved in 25 cases. Preoperative embolization proved to be a reasonable option complementary to high-grade AVMs surgery, reducing the frequency of breakthrough hemorrhages, aiding the elimination of deep feeders, and making the nidus dissection easier.

Evaluation of Olfactory Outcome After Frontolateral Approach for Treatment of Suprasellar Tumors.

OBJECTIVE: We present the findings of our prospective study assessing olfactory function outcome in patients undergoing a frontolateral approach for the resection of suprasellar lesions. METHODS: Eighteen consecutive patients (7 females, 11 males) surgically treated at our institute for suprasellar tumors were included in this prospective study. Olfactory function was evaluated at the admission and 14 days after the surgery using the standard 12-item "Sniffin' Sticks" screening (SSS) test. The olfactory outcome was correlated to the following variables: tumor type, size, consistency, and extent of vertical and lateral growth. RESULTS: Preoperative and postoperative SSS test mean values were, respectively, 9.11 and 8.72 (not significant: P = 0.274). In only 1 case (5%), with larger suprasellar extension, the difference between preoperative and postoperative SSS was ≥3 (reduction of 5 points). At the subjective evaluation, no patient stated a deficit in smelling. CONCLUSION: The frontolateral craniotomy is a minimally invasive route to treat suprasellar tumors and has a low approach-related morbidity. It allows tumor resection with low risk for the olfactory function. A risk factor for postoperative olfactory deficit could be significant brain retraction.

Surgical management of cerebellopontine angle arachnoid cysts associated with hearing deficit in pediatric patients.

OBJECTIVE Few cases of cerebellopontine angle (CPA) arachnoid cysts in pediatric patients have been described in the literature, and in only 2 of these cases were the patients described as suffering from hearing deficit. In this article, the authors report on 3 pediatric patients with CPA arachnoid cysts (2 with hearing loss and 1 with recurrent headaches) who underwent neurosurgical treatment at the authors' institution. METHODS Four pediatric patients were diagnosed with CPA arachnoid cysts at the International Neuroscience Institute during the period from October 2004 through August 2012, and 3 of these patients underwent surgical treatment. The authors describe the patients' clinical symptoms, the surgical approach, and the results on long-term follow-up. RESULTS One patient (age 14 years) who presented with headache (without hearing deficit) became asymptomatic after surgical treatment. The other 2 patients who underwent surgical treatment both had hearing loss. One of these children (age 9 years) had recent-onset hypacusia and experienced complete recovery immediately after the surgery. The other (age 6 years) had a longer history (2 years) of progressive hearing loss and showed an interruption of the deficit progression and only mild improvement at the follow-up visit. CONCLUSIONS CPA arachnoid cysts are uncommon in pediatric patients. The indication and timing of the surgical treatment are fundamental, especially when a hearing deficit is present.

Parasagittal meningiomas: Our surgical experience and the reconstruction technique of the superior sagittal sinus.

BACKGROUND: The radical resection of parasagittal meningiomas without complications and recurrences is the goal of the neurosurgeon. Nowadays, different managements are proposed. This study describes our surgical technique during the lesional excision and the reconstruction of the superior sagittal sinus (SSS). METHODS: The total removal (Simpson I and II) of parasagittal meningiomas (WHO grade I and II) was obtained in 75 patients from September 2000 to January 2010. The indocyanine green videoangiography was used before the dural opening and, when necessary, to identify and preserve the cortical veins. The surgery of the SSS was performed in accordance with Sindou's classification, and its reconstruction was achieved through the use of a patch of galea capitis. RESULTS: We had no cases of recurrence and thrombotic occlusion of the SSS in 5 years after the reconstruction. No complications were observed in 65 patients, and no cases of mortality were reported. Neurological focal deficits were observed in 5 patients. A brain swelling and a venous infarction were observed in 1 patient. Only one case of thrombotic occlusion was observed. A cerebrospinal fluid leak was observed in 2 patients, and a systemic complication was found in 1 patient. CONCLUSION: Several factors contribute to the success of the parasagittal meningioma surgery. We consider the preservation of the cortical veins to be important, and, when possible, we recommend the reconstruction of the anterior third of the SSS. Our experience has led us to believe that until now surgery is a winning choice if practiced by expert hands.

Intracranial aneurysms and optic glioma--an unusual combination: a case report.

BACKGROUND: The coexistence of glial high grade tumors (glioblastoma, anaplastic astrocytoma) and cerebral aneurysms is common but the association with optic glioma is rare. The treatment of these associated lesions is problematic. CASE PRESENTATION: A 36-year-old white woman presented to our institution with recurrent attacks of headache. Her preoperative radiological studies revealed a lesion of her left optic nerve with extension to the optic chiasma, an aneurysmatic dilatation of the left carotid bifurcation, a second aneurysm on the left of her middle cerebral artery, and a third one on her right anterior cerebral artery in the A2 tract. A left pterional approach was used to remove the tumor and clip the three aneurysmatic dilatations in a single stage. CONCLUSIONS: We report this unusual case of optic glioma associated to multiples aneurysms and review the pertinent literature. An adequate knowledge of this association is mandatory to plan the correct approach to avoid complications.

Giant aneurysm of distal posterior inferior cerebellar artery: a case report and review of the literature.

INTRODUCTION: Aneurysms in the vertebrobasilar system are rare and in the distal segment of the posterior inferior cerebellar artery they are even less frequent. Giant aneurysms are also rare in the posterior cranial fossa. Giant aneurysms of the distal posterior inferior cerebellar artery generally can have mainly compressive effects on the adjacent structures and they can be mistaken for tumors. CASE PRESENTATION: We report the case of a 74-year-old Italian woman who presented with a complaint of dizziness. Her dizziness was found to be a result of aneurysmal dilatation arising from the distal segment of the right posterior inferior cerebellar artery. A mid-line suboccipital craniotomy was performed, and the aneurysm was clipped without post-operative deficits and with improvement in the patient's dizziness. In our present report, we also review the literature and discuss our case with regard to the clinical and radiological features and surgical procedure performed. CONCLUSION: To the best of our knowledge, few cases of this type of aneurysm have been described in the literature. Our patient had a good outcome after surgical treatment.