Stereotactic frame-based biopsy of infratentorial lesions via the suboccipital-transcerebellar approach with the Zamorano-Duchovny stereotactic system-a retrospective analysis of 79 consecutive cases.

OBJECTIVE: Lesions of the posterior fossa (brainstem and cerebellum) are challenging in diagnosis and treatment due to the fact that they are often located eloquently and total resection is rarely possible. Therefore, frame-based stereotactic biopsies are commonly used to asservate tissue for neuropathological diagnosis and further treatment determination. The aim of our study was to assess the safety and diagnostic success rate of frame-based stereotactic biopsies for lesions in the posterior fossa via the suboccipital-transcerebellar approach. METHODS: We performed a retrospective database analysis of all frame-based stereotactic biopsy cases at our institution since 2007. The aim was to identify all surgical cases for infratentorial lesion biopsies via the suboccipital-transcerebellar approach. We collected clinical data regarding outcomes, complications, diagnostic success, radiological appearances, and stereotactic trajectories. RESULTS: A total of n = 79 cases of stereotactic biopsies for posterior fossa lesions via the suboccipital-transcerebellar approach (41 female and 38 male) utilizing the Zamorano-Duchovny stereotactic system were identified. The mean age at the time of surgery was 42.5 years (± 23.3; range, 1-87 years). All patients were operated with intraoperative stereotactic imaging (n = 62 MRI, n = 17 CT). The absolute diagnostic success rate was 87.3%. The most common diagnoses were glioma, lymphoma, and inflammatory disease. The overall complication rate was 8.7% (seven cases). All patients with complications showed new neurological deficits; of those, three were permanent. Hemorrhage was detected in five of the cases having complications. The 30-day mortality rate was 7.6%, and 1-year survival rate was 70%. CONCLUSIONS: Our data suggests that frame-based stereotactic biopsies with the Zamorano-Duchovny stereotactic system via the suboccipital-transcerebellar approach are safe and reliable for infratentorial lesions bearing a high diagnostic yield and an acceptable complication rate. Further research should focus on the planning of safe trajectories and a careful case selection with the goal of minimizing complications and maximizing diagnostic success.

The use of quantitative pupillometry in brain death determination: preliminary findings.

PURPOSE: Quantitative pupillometry (QP) has been increasingly applied in neurocritical care as an easy-to-use and reliable technique for evaluating the pupillary light reflex (PLR). Here, we report our preliminary findings on using QP for clinical brain death (BD) determination. MATERIALS: This retrospective study included 17 patients ≥ 18 years (mean age, 57.3 years; standard deviation, 15.8 years) with confirmed BD, as defined by German Guidelines for the determination of BD. The PLR was tested using the NPi®-200 Pupillometer (Neuroptics, Laguna Hill, USA), a handheld infrared device automatically tracking and analyzing pupil dynamics over 3 s. In addition, pupil diameter and neurological pupil index (NPi) were also evaluated. RESULTS: Intracerebral bleeding, subarachnoid hemorrhage, and hypoxic encephalopathy were the most prevalent causes of BD. In all patients, the NPi was 0 for both eyes, indicating the cessation of mid-brain function. The mean diameter was 4.9 mm (± 1.3) for the right pupil and 5.2 mm (±1.2) for the left pupil. CONCLUSIONS: QP is a valuable tool for the BD certification process to assess the loss of PLR due to the cessation of brain stem function. Furthermore, implementing QP before the withdrawal of life-sustaining therapy in brain-injured patients may reduce the rate of missed organ donation opportunities. Further studies are warranted to substantiate the feasibility and potential of this technique in treating patients and identify suitable candidates for this technique during the BD certification process.

Characteristics of inflammatory and infectious diseases of the pituitary gland in patients undergoing transsphenoidal surgery.

PURPOSE: Inflammatory and infectious diseases of the pituitary gland (IIPD) are rare lesions often misdiagnosed preoperatively. Immediate surgery is indicated especially in cases of neurological impairment. However, (chronic) inflammatory processes can mimic other pituitary tumors, such as adenomas, and data on the preoperative diagnostic criteria for IIPD are sparse. METHODS: We retrospectively reviewed medical records of 1317 patients who underwent transsphenoidal surgery at our institution between March 2003 and January 2023. A total of 26 cases of histologically confirmed IIPD were identified. Patient records, laboratory parameters, and postoperative course were analyzed and compared with an age, sex, and tumor volume-matched control group of nonfunctioning pituitary adenomas. RESULTS: Pathology confirmed septic infection in ten cases, most commonly caused by bacteria (3/10) and fungi (2/10). In the aseptic group, lymphocytic hypophysitis (8/26) and granulomatous inflammation (3/26) were most frequently observed. Patients with IIPD commonly presented with endocrine and/or neurological dysfunction. No surgical mortality occurred. Preoperative radiographic findings (cystic/solid tumor mass, contrast enhancement) did not significantly differ between IIPD and adenomas. At follow-up, 13 patients required permanent hormone substitution. CONCLUSION: In conclusion, correct preoperative diagnosis of IIPD remains challenging, as neither radiographic findings nor preoperative laboratory workup unequivocally identify these lesions. Surgical treatment facilitates decompression of supra- and parasellar structures. Furthermore, this low-morbidity procedure enables the identification of pathogens or inflammatory diseases requiring targeted medical treatment, which is crucial for these patients. Establishing a correct diagnosis through surgery and histopathological confirmation thus remains of utmost importance.

Accessory nerve schwannoma extending into the fourth ventricle: case report and review of literature.

Accessory nerve schwannoma is a rare entity in patients presenting with cranial nerve (CN) deficits. Most of these tumours arise from the cisternal segment of the eleventh CN and extend caudally. Herein, we report the third case of an accessory schwannoma extending cranially into the fourth ventricle. A 61-year-old female presented with a history of variable headaches. Cerebral magnetic resonance imaging (cMRI) revealed a large inhomogeneous contrast-enhancing lesion at the craniocervical junction extending through the foramen of Magendi and concomitant hydrocephalus due to obstruction of the foramina of Luschkae. Microsurgical tumour resection was performed in the half-sitting position. Intraoperatively, the tumour arose from a vestigial fascicle of the spinal accessory nerve. At three month follow-up, neither radiological tumour recurrence nor neurological deficits were observed.

Impact of ABO-blood group type on haemorrhagic and thromboembolic complications after resection of intracranial meningiomas.

OBJECTIVE: Recent studies have suggested an impact of the ABO-blood group type on thromboembolic and haemorrhagic events following trauma and surgical procedures. However, only limited data are available on the impact of ABO-blood group types in neurosurgical patients. The goal of the present study was to evaluate the role of the ABO-blood group type on the frequency of thromboembolic and haemorrhagic complications in patients treated surgically for intracranial meningiomas at our institution. METHODS: We retrospectively analysed the medical records of consecutive patients undergoing resection of intracranial meningiomas at our institution during a period of 12.5 years (2006-2018). Clinical characteristics, modalities of surgical treatment, histopathological results and the postoperative course of patients were analysed with specific focus on ABO-blood group typing results, need for transfusion of blood products, events of postoperative thromboembolism and intracranial re-haemorrhage requiring surgical revision, as well as in-hospital mortality. RESULTS: A total of 1,782 patients were included in this study. Based on the ABO-blood group type, patients were subdivided into four categories, corresponding to their ABO-blood group: Blood group A (n = 773; 43%); blood group B (n = 222; 12%); blood group AB (n = 88; 5%); and blood group O (n = 699; 39%). Intracranial re-haemorrhage requiring re-craniotomy and haematoma evacuation occurred in a total of 49 patients (2.7%). Thromboembolic events such as pulmonary embolism occurred in a total of 27 patients (1.5%). Statistical analysis showed no significant differences regarding the ABO-blood group type in patients suffering from re-haemorrhage or thromboembolism compared with patients with uneventful course after surgery. The overall in-hospital mortality rate was 0.17% (n = 3). CONCLUSION: Our findings suggest a lack of relevance of the ABO-blood group type regarding haemorrhagic and thromboembolic complications in patients undergoing neurosurgical meningioma resection.

Interracial anatomical differences in the transsphenoidal approach to the sellar region.

OBJECTIVE: Injury to vascular structures such as the internal carotid artery (ICA) is a rare but catastrophic complication of minimally invasive transsphenoidal surgery. Thorough preoperative planning, and knowledge of anatomical landmarks, such as the intercarotid distance (ICD) reduce this risk. Numerous anatomical studies have been conducted regarding the transsphenoidal approach, but none have taken racial disparities into account. METHODS: Since differences of the cranium, especially of the skull base exist, we sought to analyze anatomical differences of the sellar region in thin sliced T2-weighted MRI scans of 187 (87 male and 100 female) Asian, African American and Caucasian patients provided by the 'Human Connectome Project' (HCP). RESULTS: We found significant differences in the ICD between males and females across all races. Furthermore, we found that the ICD was up to 2.4 mm smaller in the Caucasian cohort compared to the African American/Asian cohort. CONCLUSION: These findings indicate that racial disparities regarding the sellar anatomy should be considered in patients undergoing pituitary surgery.

The value of intraoperative MRI for resection of functional pituitary adenomas-a critical assessment of a consecutive single-center series of 114 cases.

This series sought to evaluate the role of intraoperative MRI (iMRI) for resection of functional pituitary adenomas (FPAs). We retrospectively reviewed clinical data of 114 consecutive FPAs with excessive hormone secretion treated with transsphenoidal surgery and iMRI during 01/2010-12/2017. We focused on iMRI findings, extend of resection and postoperative hormonal remission. Variables of incomplete resections and persistent hormone excess were evaluated by binary regression. Patients with FPAs presented with hypercortisolism (n = 23, 20%), acromegaly (n = 56, 49%), and as prolactinomas (n = 35, 31%) resistant to medical treatment. Preoperative MRI showed 81 macroadenomas (71%) and optic system involvement in 41 cases (36%). IMRI was suggestive for residual tumor in 51 cases (45%). Re-inspection of the cavity cleared equivocal findings in 16 cases (14%). Additional tumor was removed in 22 cases (19%). Complete resection was achieved in 95 cases (83%). Postoperative morbidity was low (1.7% revision surgeries, 0.8% permanent diabetes insipidus). Overall hormonal remission-rate was 59% (hypercortisolism 78%, acromegaly 52%, prolactinoma 57%). Supra- and parasellar invasion and preoperative visual impairment were significant predictors for incomplete resections despite use of iMRI. Risk for persistent hormone excess was increased sevenfold after incomplete resections. IMRI enabled reliable identification of tumor remnants during surgery and triggered further resection in a considerable proportion of cases. Nevertheless, tumor size and invasiveness set persistent boundaries to the completeness of resections. The low rate of surgical complications could point at a less invasive iMRI-guided surgical approach while achieving a complete tumor resection was a crucial determinant for hormonal outcome.

The use of quantitative pupillometry in patients with pituitary tumors: a technical note.

BACKGROUND: Pituitary tumors may cause compression of the optic chiasm, resulting in decreased visual acuity. Therefore, decompression of the optic chiasm is a major goal of surgical treatment in such patients. Quantitative pupillometry has been used in various clinical settings for assessing the optic system but has not been applied in patients with pituitary tumors. This study aimed to evaluate the potential of this technique to improve treatment modalities in patients undergoing surgical resection of pituitary tumors. METHOD: Pupillometry using the automated NPi 200® Pupillometer was performed in seven patients who underwent surgical resection of large pituitary tumors at the University of Heidelberg in 2018. The neurological pupil index (NPi) was assessed preoperatively and postoperatively, and correlations with visual acuity and magnetic resonance imaging (MRI) findings regarding optic chiasm compression were determined. RESULTS: All patients experienced visual disturbance due to a large pituitary tumor. The NPi was < 4.0 in all patients in at least one pupil. Intraoperative MRI demonstrated successful decompression of the optic chiasm in all cases. Postoperatively, the NPi values increased, and this increase was correlated with improved visual acuity. CONCLUSIONS: We found that quantitative pupillometry can detect optic chiasm compression in patients with pituitary tumors. Furthermore, postoperative improvement of NPi values may indicate sufficient decompression of the optic chiasm. Further studies are warranted to substantiate the granularity of this technique to gain valuable information for patients with pituitary tumors who are indicated for surgery.

Relevance of comorbidities and antithrombotic medication as risk factors for reoperation in patients with chronic subdural hematoma.

In an aging Western society, the incidence of chronic subdural hematomas (cSDH) is continuously increasing. In this study, we reviewed our clinical management of cSDH patients and identified predictive factors for the need of reoperation due to residual or recurrent hematomas with a focus on the use of antithrombotic drugs. In total, 623 patients who were treated for cSDH with surgical evacuation between 2006 and 2016 at our department were retrospectively analyzed. Clinical and radiological characteristics and laboratory parameters were investigated as possible predictors of reoperation with univariate and multivariate analyses. Additionally, clinical outcome measures were compared between patients on anticoagulants, on antiplatelets, and without antithrombotic medication. In univariate analyses, patients on anticoagulants and antiplatelets presented significantly more often with comorbidities, were significantly older, and their risk for perioperative complications was significantly increased. Nevertheless, their clinical outcome was comparable to that of patients without antithrombotics. In multivariate analysis, only the presence of comorbidities, but not antithrombotics, was an independent predictor for the need for reoperations. Patients on antithrombotics do not seem to necessarily have a significantly increased risk for residual hematomas or rebleeding requiring reoperation after cSDH evacuation. More precisely, the presence of predisposing comorbidities might be a key independent risk factor for reoperation. Importantly, the clinical outcomes after surgical evacuation of cSDH are comparable between patients on anticoagulants, antiplatelets, and without antithrombotics.

Long-Term Results of Neurological Outcome, Quality of Life, and Cosmetic Outcome After Cranioplastic Surgery: A Single Center Study of 202 Patients.

Objective: An increased interest in the surgical procedures of decompressive craniectomy (DC) and subsequent cranioplasty (CP) has emerged during the last decades with specific focus on mortality and complication rates. The aim of the present study was to evaluate long-term neurological and cosmetic outcomes as well as Quality of Life (QoL) after CP surgery. Methods: We retrospectively reviewed the medical records of CP patients treated at our institution between 2004 and 2014 and performed a follow-up examination, with evaluation of neurological outcome using the modified Rankin Scale (mRS) and the Glasgow outcome scale (GOS), QoL (SF-36 and EQ-5D-3L). Furthermore, the cosmetic results after CP were analyzed. Results: A total of 202 CP-patients were included in the present study. The main indications for DC and subsequent CP were space-occupying cerebral ischemia (32%), traumatic brain injury (TBI, 26%), intracerebral or subarachnoid hemorrhage (32%) and infection (10%). During a mean follow-up period of 91.9 months 46/42.6% of patients had a favorable neurological outcome (mRS ≤ 3/GOS ≥ 4). Patients with ischemia had a significant worse outcome (mRS 4.3 ± 1.5) compared with patients after TBI (3.1 ± 2.3) and infectious diseases requiring CP (2.4 ± 2.3). The QoL analysis showed that <1/3rd of patients (31.2%) had a good QoL (SF-36) with a mean EQ-5D-VAS of 59 ± 26. Statistical analysis confirmed a significant worse QoL of ischemia patients compared to other groups whereas multivariate regression analysis showed no other factors which may had an impact on the QoL. The majority (86.5%) of patients were satisfied with the cosmetic result after CP and regression analysis showed no significant factors associated with unfavorable outcomes. Conclusion: Long-term outcome and QoL after CP were significantly influenced by the medical condition requiring DC. Early detection and evaluation of QoL after CP may improve the patient's outcome due to an immediate initiation of targeted therapies (e.g., occupational- or physiotherapy).

Aggressive pituitary adenoma in the context of Lynch syndrome: a case report and literature review on this rare coincidence.

PURPOSE: Lynch Syndrome (LS) is a cancer-predisposing condition resulting from hereditary mutation of DNA mismatch repair genes. Gastrointestinal, urogenital, and endometrial carcinomas are well-known to predominantly occur in LS patients. In contrast, there are only few reports on brain tumours in the context of LS and to date intracranial tumour manifestation appear to be rather coincidental. METHODS: We present the case of a 56-year-old female developing aggressive lactotroph pituitary adenoma following a history of multiple Lynch-associated malignomas and having a confirmed MSH2 mutation. Furthermore, we performed a literature review via PubMed using the search terms 'Lynch Syndrome', 'HNPCC', 'MMR mutation' combined with 'intracranial tumour', 'sellar tumour', 'pituitary adenoma', or 'pituitary carcinoma', focusing on other reported cases and treatment regimens. RESULTS: A handful of studies have indicated an increased frequency of brain tumours in the context of LS, predominantly glioblastoma and less frequently low-grade glioma or other brain tumours. Based on our literature review, we summarized the known instances of pituitary adenoma in LS patients, including the present case. Furthermore, we reviewed the common recommendation of using temozolomide (TMZ) for treatment of aggressive pituitary adenoma or carcinoma and found strong indication that it might be insufficient in LS patients, while PD-1 blockade could be a promising treatment option. CONCLUSIONS: Combined with our case, there is a growing body of evidence that intracranial tumours and in particular those of the sellar region might be more prevalent in LS patients than previously assumed, due to their genetic profile substantially affecting viability and efficacy of treatment options. Clinical signs of aggressive tumour growth in combination with irresponsiveness to standard treatment in case of recurrence should lead to further diagnostic measures, because revelation of germline MMR mutations would call for an extended screening for other neoplastic manifestations and would markedly influence further treatment.

Long-term complications and implant survival rates after cranioplastic surgery: a single-center study of 392 patients.

Cranioplasty (CP) is a standard procedure in neurosurgical practice for patients after (decompressive) craniectomy. However, CP surgery is not standardized, is carried out in different ways, and is associated with considerable complication rates. Here, we report our experiences with the use of different CP materials and analyze long-term complications and implant survival rates. We retrospectively studied patients who underwent CP surgery at our institution between 2004 and 2014. Binary logistic regression analysis was performed in order to identify risk factors for the development of complications. Kaplan-Meier analysis was used to estimate implant survival rates. A total of 392 patients (182 females, 210 males) with a mean age of 48 years were included. These patients underwent a total of 508 CP surgeries. The overall complication rate of primary CP was 33.2%, due to bone resorption/loosening (14.6%) and graft infection (7.9%) with a mean implant survival of 120 ± 5 months. Binary logistic regression analysis showed that young age (< 30 years) (p = 0.026, OR 3.150), the presence of multidrug-resistant bacteria (p = 0.045, OR 2.273), and cerebrospinal fluid (CSF) shunt (p = 0.001, OR 3.137) were risk factors for postoperative complications. The use of titanium miniplates for CP fixation was associated with reduced complication rates and bone flap osteolysis as well as longer implant survival rates. The present study highlights the risk profile of CP surgery. Young age (< 30 years) and shunt-dependent hydrocephalus are associated with postoperative complications especially due to bone flap autolysis. Furthermore, a rigid CP fixation seems to play a crucial role in reducing complication rates.

Prothrombin complex concentrate for vitamin K antagonist reversal in traumatic intracranial hemorrhage.

OBJECTIVE: Administration of prothrombin complex concentrate (PCC) is recommended for vitamin K antagonist (VKA) reversal in patients with severe bleeding complications. However, there are only limited data available on its use for VKA reversal in patients with traumatic intracranial hemorrhage (ICH). METHODS: Data from all anticoagulated patients referred to our hospital for treatment of traumatic ICH and who received PCC for anticoagulation reversal were retrospectively analysed with specific focus on bleeding and thromboembolic complications during the further in-hospital course. RESULTS: A total of 142 patients were included in the present study. The median age was 78 years (Interquartile range [IQR]: 72-84) and the median Glasgow Coma Scale (GCS) score on admission was 12 (IQR: 7-14). Median International Normalized Ratio (INR) on admission was 2.5 [IQR: 2.0-3.3] and decreased to 1.2 [IQR: 1.1-1.3] following administration of a median dose of 2000 I.U. PCC [IQR: 1500-2625]. The in-hospital mortality rate was 13% and the median GCS of survivors at discharge was 14 [IQR: 12-15]. Thromboembolic events after PCC administration occurred in 4 patients (2.8%). The overall one-year mortality rate in this patient cohort was 49%. CONCLUSIONS: PCC administration rapidly normalises INR and facilitates urgent neurosurgical procedures in anticoagulated patients with traumatic ICH.

Polymethylmethacrylate patient-matched implants (PMMA-PMI) for complex and revision cranioplasty: analysis of long-term complication rates and patient outcomes.

Objective: Cranioplasty (CP) is associated with high complication rates and patient-matched implants (PMI) are frequently used for CP. However, only limited data are available regarding complication rates of PMI-based CP after complex or failed primary CP. Here we report our experience with the use of polymethylmethacrylate (PMMA) PMI for this purpose.Method: We analyzed all patients with complex or failed primary CP and subsequent implantation of PMMA-PMI between 2010 and 2015 at our institution.Results: A total of 67 patients (29 females, 38 males) with a mean age of 43 years (range: 13-74 years) were included in the study. Primary PMI-CP was performed in 18 patients with destructive or osteolytic bone tumors. Secondary PMI-CP was performed in 49 patients. Complications occurred in 14 patients with an overall complication rate of 21.7% during a mean follow-up of 39.7 ± 23.4 month. Approximately two-thirds of the patients reported a good quality of life after the initial event and subsequent CP. The majority of patients (>90%) was satisfied with the cosmetic result.Conclusion: Surgical CP with PMMA-PMI appears to be a suitable method for patients with failed or complex CP. Complication rates are comparable to those reported for primary CP.

Intraventricular meningiomas frequently harbor NF2 mutations but lack common genetic alterations in TRAF7, AKT1, SMO, KLF4, PIK3CA, and TERT.

Intraventricular meningiomas (IVMs) account for less than 5% of all intracranial meningiomas; hence their molecular phenotype remains unknown. In this study, we were interested whether genetic alterations in IVMs differ from meningiomas in other locations and analyzed our institutional series with respect to clinical and molecular characteristics. A total of 25 patients with surgical removal of an IVM at our department between 1986 and 2018 were identified from our institutional database. Median progression-free survival (PFS) was 79 months (range of 2-319 months) and PFS at 5 years was 86%. Corresponding tumor tissue was available for 18 patients including one matching recurrence and was subjected to targeted panel sequencing of 130 selected genes frequently mutated in brain cancers by applying a custom hybrid capture approach on a NextSeq500 instrument. Loss of chromosome 22q and 1p occurred frequently in 89 and 44% of cases. Deleterious NF2 mutations were found in 44% of IVMs (n = 8/18). In non-NF2-mutated IVMs, previously reported genetic alterations including TRAF7, AKT1, SMO, KLF4, PIK3CA, and TERT were lacking, suggesting alternative genes in the pathogenesis of non-NF2 IVMs. In silico analysis revealed possible damaging mutations of APC, GABRA6, GSE1, KDR, and two SMO missense mutations differing from previously reported ones. Interestingly, all WHO°II IVMs (n = 3) harbored SMARCB1 and SMARCA4 mutations, indicating a role of the SWI/SNF chromatin remodeling complex in aggressive IVMs.

Management of Spinal Emergencies in Patients on Direct Oral Anticoagulants.

OBJECTIVE: Spine surgeons increasingly encounter acute spinal pathologies in patients treated with direct oral anticoagulants (DOACs), but only limited data on the management of these patients are currently available. METHODS: We retrospectively analyzed patients who presented to our department with acute spinal pathology during treatment with DOAC and who required urgent surgical therapy. Patient characteristics and treatment modalities were studied, with specific focus on the management of hemostasis and surgical therapy. Furthermore, we analyzed 19 cases of spinal emergencies during DOAC treatment reported in the literature. RESULTS: A total of 12 patients were identified and included in the present analysis. Patients suffered from acute spinal cord compression caused by spinal tumor manifestation (n = 5), empyema (n = 4), degenerative spinal stenosis (n = 1), hematoma (n = 1), and vertebral body fracture/dislocation (n = 2). All patients underwent emergency surgical treatment. Prohemostatic substances were administered perioperatively in 10 patients (83%) and included administration of prothrombin complex concentrates (83%), tranexamic acid (17%), and transfusion of platelets (8%). A total of 9 patients (75%) showed postoperative improvement of neurologic symptoms, and the in-hospital mortality in this patient cohort was 17%. CONCLUSIONS: Emergency spine surgery is feasible and should be considered in patients on treatment with DOAC. The (low) risk of intraoperative bleeding complications has to be weighed against the risk of permanent disability if surgical decompression is delayed. Administration of prothrombin complex concentrates and tranexamic acid may improve the coagulation before surgery, especially in cases of unavailable specific antidotes.