Interrater Agreement of Height Assessment by Rigid Proctoscopy/ Rectoscopy for Rectal Carcinoma.

BACKGROUND: Some guidelines for rectal carcinoma consider 12 cm, measured by rigid endoscopy to be the cutoff tumor height for optional neoadjuvant chemoradiation. Measuring differences of only a few centimeters may therefore predetermine choice of further therapy. However, rigid endoscopy may exhibit similar operator dependence as do most other clinical examination methods. OBJECTIVES: Evaluation of concordance of rigid rectoscopic tumor height measurements performed by 4 experienced examiners, 2 in lithotomy and 2 in left lateral position. Assessment of tumor palpability and distance of the anal verge to the anocutaneous line were also evaluated. DESIGN: Prospective observational study. SETTING: Academic teaching hospital, referral center for colorectal surgery. PATIENTS: There were 50 patients, of whom were 35 males (70%). The median age was 72.5 years (53-88 years). MAIN OUTCOME MEASURES: Interrater agreement of tumor height assessment and tumor allocation beneath or beyond the 12-cm height limit. RESULTS: With an intraclass correlation coefficient of 0.947 (95% CI: 0.918-0.967, p < 0.001), interrater reliability of tumor height assessment was statistically rated "excellent." Despite this, in 26% of patients, there was no agreement regarding the allocation of the tumor beneath or beyond the 12-cm height limit. Furthermore there was also considerable disagreement concerning tumor palpability and the distance of the anal verge to the anocutaneous line. Patient positioning was not found to influence results. LIMITATIONS: Single center study. CONCLUSIONS: Rigid rectal endoscopy may not be a sound pivotal basis for the consideration of optional chemoradiation in rectal carcinoma. Application of a universally valid height limit obviously ignores biological variability in body frame, gender, and acquired pelvic descent. Eligibility for neoadjuvant therapy should not rely on height measurements alone. Uniform MRI or CT imaging protocols, based on agreed terminology, including factors such as tumor height relative to pelvic frame and peritoneal reflection, may be an important diagnostic addition for such decision. See Video Abstract . CLINICAL TRIAL REGISTRATION: DRKS00012758 (German National Study Registry), ST-D 406 (German Cancer Society).

A Retrospective Cohort Study Evaluating the Comparative Effectiveness of Unilateral Hemilaminectomy and Bilateral Laminectomy in the Resection of Spinal Meningiomas.

BACKGROUND AND OBJECTIVES: The primary treatment modality for spinal meningiomas (SM) is surgical resection. In recent years, minimal invasive spine surgery has gained considerable popularity, attributing its growth to advancements in surgical technologies and improved training of surgeons. Nonetheless, the suitability and effectiveness of minimal invasive spine surgery for intradural spinal tumor resection remain a subject of debate. In this cohort study, we aimed to compare the extent of resection of the unilateral hemilaminectomy approach, a less invasive technique, with the more traditional and invasive bilateral laminectomy. METHODS: We performed a retrospective cohort study including patients with SM who underwent surgery at our department between 1996 and 2020. Cohorts included patients who underwent tumor resection through bilateral laminectomy and patients who underwent a unilateral hemilaminectomy. The primary end point was extent of resection according to the Simpson classification. RESULTS: Of 131 with SM, 36 had a bilateral laminectomy and 95 were operated through a unilateral hemilaminectomy. In both groups, gross total resection, Simpson grades 1 and 2, was achieved in 94.44% and 94.74%, respectively (P = .999). The neurological outcome was also comparable in both cohorts (P = .356). Both length of hospital stay and estimated blood loss were significantly lower in the unilateral cohort (P < .05). CONCLUSION: The results of this study indicate that the unilateral hemilaminectomy yields comparable results in both oncological and neurological outcome when compared with the bilateral laminectomy. Thus, unilateral hemilaminectomy may serve as a viable and safe alternative for the surgical removal of SM.

Does Early Mobilization Following Resection of Spinal Intra-Dural Pathology Increase the Risk of Cerebrospinal Fluid Leaks?-A Dual-Center Comparative Effectiveness Research.

Background and Objectives: Prolonged bed rest after the resection of spinal intradural tumors is postulated to mitigate the development of cerebrospinal fluid leaks (CSFLs), which is one of the feared postoperative complications. Nonetheless, the empirical evidence supporting this conjecture remains limited and requires further investigation. The goal of the study was to investigate whether prolonged bed rest lowers the risk of CSFL after the resection of spinal intradural tumors. The primary outcome was the rate of CSFL in each cohort. Materials and Methods: To validate this hypothesis, we conducted a comparative effectiveness research (CER) study at two distinct academic neurosurgical centers, wherein diverse postoperative treatment protocols were employed. Specifically, one center adopted a prolonged bed rest regimen lasting for three days, while the other implemented early postoperative mobilization. For statistical analysis, case-control matching was performed. Results: Out of an overall 451 cases, we matched 101 patients from each center. We analyzed clinical records and images from each case. In the bed rest center, two patients developed a CSFL (n = 2, 1.98%) compared to four patients (n = 4, 3.96%) in the early mobilization center (p = 0.683). Accordingly, CSFL development was not associated with early mobilization (OR 2.041, 95% CI 0.365-11.403; p = 0.416). Univariate and multivariate analysis identified expansion duraplasty as an independent risk factor for CSFL (OR 60.33, 95% CI: 0.015-0.447; p < 0.001). Conclusions: In this CER, we demonstrate that early mobilization following the resection of spinal intradural tumors does not confer an increased risk of the development of CSFL.

Resection of Intramedullary Hemangioblastoma: Timing of Surgery and Its Impact on Neurological Outcome and Quality of Life.

Background and Objectives: Spinal intramedullary hemangioblastomas (SIMH) are benign vascular lesions that are pathological hallmarks of von Hippel-Lindau disease (vHL) and constitute the third most common intramedullary neoplasm in adults. So far, maximal and safe resection is the first choice of treatment. However, as SIMH show no malignant transformation, it remains unclear whether surgical resection is beneficial for all patients. Materials and Methods: We retrospectively analyzed the surgical outcomes of 27 patients who were treated between 2014 and 2022 at our neurosurgical department and investigated potential risk factors that influence the surgical outcome. Pre- and postoperative neurological status were classified according to the McCormick scale. Furthermore, surgical quality indicators, such as length of hospital stay (LOS; days), 90-day readmissions, nosocomial infections, and potential risk factors that might influence the surgical outcome, such as tumor size and surgical approach, have been analyzed. In addition to that, patients were asked to fill out the EQ-5D-3L questionnaire to assess their quality of life after surgery. Results: Surgery on SIMH patients that display no or minor neurological deficits (McCormick scale I or II) is associated with a favorable postoperative outcome and overall higher quality of life compared to those patients that already suffer from severe neurological deficits (McCormick scale III or IV). Conclusion: Early surgical intervention prior to the development of severe neurological deficits may offer a better neurological outcome and quality of life.

Intraoperative MRI-Guided Resection Is Not Superior to 5-Aminolevulinic Acid Guidance in Newly Diagnosed Glioblastoma: A Prospective Controlled Multicenter Clinical Trial.

PURPOSE: Prospective data suggested a superiority of intraoperative MRI (iMRI) over 5-aminolevulinic acid (5-ALA) for achieving complete resections of contrast enhancement in glioblastoma surgery. We investigated this hypothesis in a prospective clinical trial and correlated residual disease volumes with clinical outcome in newly diagnosed glioblastoma. METHODS: This is a prospective controlled multicenter parallel-group trial with two center-specific treatment arms (5-ALA and iMRI) and blinded evaluation. The primary end point was complete resection of contrast enhancement on early postoperative MRI. We assessed resectability and extent of resection by an independent blinded centralized review of preoperative and postoperative MRI with 1-mm slices. Secondary end points included progression-free survival (PFS) and overall survival (OS), patient-reported quality of life, and clinical parameters. RESULTS: We recruited 314 patients with newly diagnosed glioblastomas at 11 German centers. A total of 127 patients in the 5-ALA and 150 in the iMRI arm were analyzed in the as-treated analysis. Complete resections, defined as a residual tumor ≤0.175 cm³, were achieved in 90 patients (78%) in the 5-ALA and 115 (81%) in the iMRI arm (P = .79). Incision-suture times (P < .001) were significantly longer in the iMRI arm (316 v 215 [5-ALA] minutes). Median PFS and OS were comparable in both arms. The lack of any residual contrast enhancing tumor (0 cm³) was a significant favorable prognostic factor for PFS (P < .001) and OS (P = .048), especially in methylguanine-DNA-methyltransferase unmethylated tumors (P = .006). CONCLUSION: We could not confirm superiority of iMRI over 5-ALA for achieving complete resections. Neurosurgical interventions in newly diagnosed glioblastoma shall aim for safe complete resections with 0 cm³ contrast-enhancing residual disease, as any other residual tumor volume is a negative predictor for PFS and OS.

Quality indicators and early adverse in surgery for atypical meningiomas: A 16-year single centre study and systematic review of the literature.

Introduction: Atypical meningiomas represent approximately 20% of all intracranial meningiomas and are characterized by distinct histopathological criteria and an increased risk of postoperative recurrence. Recently, quality indicators have been introduced to monitor quality of the delivered care. Research question: Which quality indicators/outcome measures are being applied in patients being operated for atypical meningiomas? What are risk factors associated with poor outcome? How is the surgical outcome and which quality indicators are reported in the literature? Material and methods: The primary outcomes of interest were 30-days readmission-, 30-day reoperation-, 30-day mortality-, 30-day nosocomial infection- and the 30-day surgical site infection (SSI) rate, CSF-leakage, new neurological deficit, medical complications, and lengths of stay. The secondary aim was the identification of prognostic factors for the mentioned primary outcomes. A systematic review of the literature was performed screening studies for the mentioned outcomes. Results: We included 52 patients. 30-days outcomes in terms of unplanned reoperation were 0%, unplanned readmission 7.7%, mortality 0%, nosocomial infection 17.3%, and SSI 0%. Any adverse event occurred in 30.8%. Preoperative C-reactive protein over 5 â€‹mg/l was independent factor for the occurrence of any postoperative adverse event (OR: 17.2, p â€‹= â€‹0.003). A total of 22 studies were included into the review. Discussion and conclusion: The 30-days outcomes at our department were comparable with reported outcomes in the literature. Currently applied quality indicators are helpful in determining the postoperative outcome but mainly report the indirect outcome after surgery and are influenced of patient, tumor and treatment related factors. Risk adjustment is vital.

The Role of Prolonged Bed Rest in Postoperative Cerebrospinal Fluid Leakage After Surgery of Intradural Pathology-A Retrospective Cohort Study.

BACKGROUND: Postoperative cerebrospinal fluid leakage (CSFL) is a feared complication after surgery on intradural pathologies and may cause postoperative complications and subsequently higher treatment costs. OBJECTIVE: To assess whether prolonged bed rest may lower the risk of CSFL. METHODS: We performed a retrospective cohort study including patients with intradural pathologies who underwent surgery at our department between 2013 and 2021. Cohorts included patients who completed 3 days of postoperative bed rest and patients who were mobilized earlier. The primary end point was the occurrence of clinically proven CSFL. RESULTS: Four hundred and thirty-three patients were included (female [51.7%], male [48.3%]) with a mean age of 48 years (SD ±20). Bed rest was ordered in 315 cases (72.7%). In 7 cases (N = 7/433, 1.6%), we identified a postoperative CSFL. Four of them (N = 4/118) did not preserve bed rest, showing no significant difference to the bed rest cohort (N = 3/315; P = .091). In univariate analysis, laminectomy (N = 4/61; odds ratio [OR] 8.632, 95% CI 1.883-39.573), expansion duraplasty (N = 6/70; OR 33.938, 95% CI 4.019-286.615), and recurrent surgery (N = 5/66; OR 14.959, 95% CI 2.838-78.838) were significant risk factors for developing CSFL. In multivariate analysis, expansion duraplasty was confirmed as independent risk factor (OR 33.937, 95% CI 4.018-286.615, P = .001). In addition, patients with CSFL had significant higher risk for meningitis (N = 3/7; 42.8%, P = .001). CONCLUSION: Prolonged bed rest did not protect patients from developing CSFL after surgery on intradural pathologies. Avoiding laminectomy, large voids, and minimal invasive approaches may play a role in preventing CSFL. Furthermore, special caution is indicated if expansion duraplasty was done.

Quality indicators for evaluating the 30-day postoperative outcome in pediatric brain tumor surgery: a 10-year single-center study and systematic review of the literature.

OBJECTIVE: Surgery is the cornerstone in the management of pediatric brain tumors. To provide safe and effective health services, quantifying and evaluating quality of care are important. To do this, there is a need for universal measures in the form of indicators reflecting quality of the delivered care. The objective of this study was to analyze currently applied quality indicators in pediatric brain tumor surgery and identify factors associated with poor outcome at a tertiary neurosurgical referral center in western Norway. METHODS: All patients younger than 18 years of age who underwent surgery for an intracranial tumor at the Department of Neurosurgery at Haukeland University Hospital in Bergen, Norway, between 2009 and 2020 were included. The primary outcomes of interest were classic quality indicators: 30-day readmission, 30-day reoperation, 30-day mortality, 30-day nosocomial infection, and 30-day surgical site infection (SSI) rates; and length of stay. The secondary aim was the identification of risk factors related to unfavorable outcome. The authors also conducted a systematic literature review. Articles concerning pediatric brain tumor surgery reporting at least two quality indicators were of interest. RESULTS: The authors included 82 patients aged 0-17 years. The 30-day outcomes for unplanned reoperation, unplanned remission, mortality, nosocomial infection, and SSI were 9.8%, 14.6%, 0%, 6.1%, and 3.7%, respectively. Unplanned reoperation was associated with eloquent localization (p = 0.009), primary emergency surgery (p = 0.003), and CSF diversion procedures (p = 0.002). Greater tumor volume was associated with unplanned readmission (p = 0.008), nosocomial infection (p = 0.004), and CSF leakage (p = 0.005). In the systematic review, after full-text screening, 16 articles were included and provided outcome data for 1856 procedures. Overall, the 30-day mortality rate was low, varying from 0% to 9.3%. The 30-day reoperation rate varied from 1.5% to 12%. The SSI rate ranged between 0% and 3.9%, and 0% to 17.4% of patients developed CSF leakage. Four studies reported infratentorial tumor location as a risk factor for postoperative CSF leakage. CONCLUSIONS: The 30-day outcomes in the authors' department were comparable to published outcomes. The most relevant factors related to unfavorable outcomes are tumor volume and location, both of which are not modifiable by the surgeon. This highlights the importance of risk adjustment. This evaluation of quality indicators reveals concerns related to the unclear and nonstandardized definitions of outcomes. Standardized outcome definitions and documentation in a large and multicentric database are needed in the future for further evaluation of quality indicators.

Can Currently Suggested Quality Indicators Be Transferred to Meningioma Surgery?-A Single-Center Pilot Study.

BACKGROUND: Risk stratification based on standardized quality measures has become crucial in neurosurgery. Contemporary quality indicators have often been developed for a wide range of neurosurgical procedures collectively. The accuracy of tumor-inherent characteristics of patients diagnosed with meningioma remains questionable. The objective of this study was the analysis of currently applied quality indicators in meningioma surgery and the identification of potential new measures. METHODS: Data of 133 patients who were operated on due to intracranial meningiomas were subjected to a retrospective analysis. The primary outcomes of interest were classical quality indicators such as the 30-day readmission, 30-day reoperation, 30-day mortality, 30-day nosocomial infection, and the 30-day surgical site infection rate. Uni- and multivariate analyses were performed. The occurrence of a new postoperative neurologic deficit was analyzed as a potential new quality indicator. RESULTS: The overall unplanned readmission rate was 3.8%; 13 patients were reoperated within 30 days (9.8%). The 30-day nosocomial infection and surgical site infection rates were 6.8 and 1.5%, respectively. A postoperative new neurologic deficit or neurologic deterioration as a currently assessed quality feature was observed in 12 patients (9.2%). The edema volume on preoperative scans proved to have a significant impact on the occurrence of a new postoperative neurologic deficit (p = 0.023). CONCLUSIONS: Classical quality indicators in neurosurgery have proved to correlate with considerable deterioration of the patient's health in meningioma surgery and thus should be taken into consideration for application in meningioma patients. The occurrence of a new postoperative neurologic deficit is common and procedure specific. Thus, this should be elucidated for application as a complementary quality indicator in meningioma surgery.

Postoperative surveillance in cranial and spinal tumor neurosurgery: when is this warranted?

OBJECTIVE: The outbreak of COVID-19 and the sudden increase in the number of patients requiring mechanical ventilation significantly affected the management of neurooncological patients. Hospitals were forced to reallocate already scarce human resources to maximize intensive care unit (ICU) capacities, resulting in a significant postponement of elective procedures for patients with brain and spinal tumors, who traditionally require elective postoperative surveillance on ICU or intermediate care wards. This study aimed to characterize those patients in whom postoperative monitoring is required by analyzing early postoperative complications and associated risk factors. METHODS: All patients included in the analysis experienced benign or malignant cerebral or intradural tumors and underwent surgery between September 2017 and May 2019 at University Hospital Münster, Germany. Patient data were generated from a semiautomatic, prospectively designed database. The occurrence of adverse events within 24 hours and 30 days postoperatively-including unplanned reoperation, postoperative hemorrhage, CSF leakage, and pulmonary embolism-was chosen as the primary outcome measure. Furthermore, reasons and risk factors that led to a prolonged stay on the ICU were investigated. By performing multivariable logistic regression modeling, a risk score for early postoperative adverse events was calculated by assigning points based on beta coefficients. RESULTS: Eight hundred eleven patients were included in the study. Eleven patients (1.4%) had an early adverse event within 24 hours, which was either an unplanned reoperation (0.9%, n = 7) or a pulmonary embolism (0.5%, n = 4) within 24 hours. To predict the incidence of early postoperative complications, a score was developed including the number of secondary diagnoses, BMI, and incision closure time, termed the SOS score. According to this score, 0.3% of the patients were at low risk, 2.5% at intermediate risk, and 12% at high risk (p < 0.001). CONCLUSIONS: Postoperative surveillance in cranial and spinal tumor neurosurgery might only be required in a distinct patient collective. In this study, the authors present a new score allowing efficient prediction of the likelihood of early adverse events in patients undergoing neurooncological procedures, thus helping to stratify the necessity for ICU or intermediate care unit beds. Nevertheless, validation of the score in a multicenter prospective setting is needed.

Minimally Invasive Facetectomy and Fusion for Resection of Extensive Dumbbell Tumors in the Lumbar Spine.

Background and Objectives: Resection of dumbbell tumors can be challenging, and facet joint sparing approaches carry the risk of incomplete resection. In contrast, additional facetectomy may allow better surgical exposure at the cost of spinal stability. The aim of this study is to compare facet-sparing and facetectomy approaches for the treatment of lumbar spine dumbbell tumors. Materials and Methods: In a cohort study setting, we analyzed Eden type 2 and 3 tumors operated in our department. Conventional facet-sparing microsurgical or facetectomy approaches with minimally invasive fusions were performed according to individual surgeons' preference. Primary outcomes were extent of resection and tumor progression over time. Secondary outcomes were perioperative adverse events. Results: Nineteen patients were included. Nine patients were operated on using a facet-sparing technique. Ten patients underwent facetectomy and fusion. While only one patient (11%) in the facet-sparing group experienced gross total resection (GTR), this was achieved for all patients in the facetectomy group (100%). The relative risk (RR) for incomplete resection in the facet-sparing cohort was 18.7 (95% CI 1.23-284.047; p = 0.035). In addition, time to progression was shorter in the facet-sparing cohort (p = 0.022) and all patients with a residual tumor underwent a second resection after a median follow-up time of 42 months (IQR 25-66). Conclusions: Minimally invasive resection of lumbar Eden type 2 and 3 dumbbell tumors including facetectomy in combination with instrumentation appears to be safe and superior to the facet-sparing approach in terms of local tumor control.

Stereotactic Radiosurgery for Benign Cavernous Sinus Meningiomas: A Multicentre Study and Review of the Literature.

Cavernous sinus meningiomas (CSMs) remain a surgical challenge due to the intimate involvement of their contained nerves and blood vessels. Stereotactic radiosurgery (SRS) is a safe and effective minimally invasive alternative for the treatment of small- to medium-sized CSMs. Objective: To assess the medium- to long-term outcomes of SRS for CSMs with respect to tumour growth, prevention of further neurological deterioration and improvement of existing neurological deficits. This multicentric study included data from 15 European institutions. We performed a retrospective observational analysis of 1222 consecutive patients harbouring 1272 benign CSMs. All were treated with Gamma Knife stereotactic radiosurgery (SRS). Clinical and imaging data were retrieved from each centre and entered into a common database. All tumours with imaging follow-up of less than 24 months were excluded. Detailed results from 945 meningiomas (86%) were then analysed. Clinical neurological outcomes were available for 1042 patients (85%). Median imaging follow-up was 67 months (mean 73.4, range 24-233). Median tumour volume was 6.2 cc (+/-7), and the median marginal dose was 14 Gy (+/-3). The post-treatment tumour volume decreased in 549 (58.1%), remained stable in 336 (35.6%) and increased in only 60 lesions (6.3%), yielding a local tumour control rate of 93.7%. Only 27 (2.8%) of the 60 enlarging tumours required further treatment. Five- and ten-year actuarial progression-free survival (PFS) rates were 96.7% and 90.1%, respectively. Tumour control rates were higher for women than men (p = 0.0031), and also for solitary sporadic meningiomas (p = 0.0201). There was no statistically significant difference in outcome for imaging-defined meningiomas when compared with histologically proven WHO Grade-I meningiomas (p = 0.1212). Median clinical follow up was 61 months (mean 64, range 6-233). Permanent morbidity occurred in 5.9% of cases at last follow-up. Stereotactic radiosurgery is a safe and effective method for treating benign CSM in the medium term to long term.

Combined Fluorescence-Guided Resection and Intracavitary Thermotherapy with Superparamagnetic Iron-Oxide Nanoparticles for Recurrent High-Grade Glioma: Case Series with Emphasis on Complication Management.

BACKGROUND: Concepts improving local tumor control in high-grade glioma (HGG) are desperately needed. The aim of this study is to report an extended series of cases treated with a combination of 5-ALA-fluorescence-guided resection (FGR) and intracavitary thermotherapy with superparamagnetic iron oxide nanoparticles (SPION). METHODS: We conducted a single-center retrospective review of all recurrent HGG treated with FGR and intracavitary thermotherapy (n = 18). Patients underwent six hyperthermia sessions in an alternating magnetic field and received additional adjuvant therapies on a case-by-case basis. RESULTS: Nine patients were treated for first tumor recurrence; all other patients had suffered at least two recurrences. Nine patients received combined radiotherapy and thermotherapy. The median progression-free survival was 5.5 (95% CI: 4.67-6.13) months and median overall survival was 9.5 (95% CI: 7.12-11.79) months. No major side effects were observed during active treatment. Thirteen patients (72%) developed cerebral edema and more clinical symptoms during follow-up and were initially treated with dexamethasone. Six (33%) of these patients underwent surgical removal of nanoparticles due to refractory edema. CONCLUSIONS: The combination of FGR and intracavitary thermotherapy with SPION provides a new treatment option for improving local tumor control in recurrent HGG. The development of cerebral edema is a major issue requiring further refinements of the treatment protocol.

Classical and disease-specific quality indicators in glioma surgery-Development of a quality checklist to improve treatment quality in glioma patients.

BACKGROUND: There is a pressing demand for more accurate, disease-specific quality measures in the field of neurosurgery. Aiming at most adequately measuring and reflecting the quality of glioma therapy, we developed a novel quality indicator bundle in form of a checklist for all patients that are treated operatively for glioma. METHODS: On the basis of possible glioma-specific quality indicators retrieved from the literature and quality guidelines, a multidisciplinary team developed a checklist containing 13 patient-need-specific outcome measures. Subsequently, the checklist was prospectively applied to a total of 78 patients compared with a control group consisting of 322 patients. A score was generated based on the maximum of quality measures achieved. RESULTS: Significant improvements in quality after prospectively introducing the checklist were achieved for supplemental physical and occupational therapy during inpatient stay (89.4% vs 100%, P = .002), consultation of a social worker during inpatient stay (64% vs 92.3%, P < .001), psycho-oncological screening (14.3% vs 70.5%, P < .001), psycho-oncological consultation (31.1% vs 82.1%, P < .001), and consultation of the palliative care team (20% vs 40%, P = .031). Overall, after introduction of the checklist one-third (n = 23) of patients reached best-practice measures in all categories, and over half of the patients (n = 44) achieved above 90% with respect to the outcome measures. CONCLUSIONS: Aiming at ensuring comprehensive, consistent, and timely care of glioma patients, the implementation of the checklist for routine use in glioma surgery represents an efficient, easily reproducible, and powerful tool for significant improvements.

Fluorescence real-time kinetics of protoporphyrin IX after 5-ALA administration in low-grade glioma.

OBJECTIVE: 5-Aminolevulinic acid (5-ALA) induces fluorescence in high-grade glioma (HGG), which is used for resection. However, the value of 5-ALA-induced fluorescence in low-grade glioma (LGG) is unclear. Time dependency and time kinetics have not yet been investigated. The purpose of this study was to investigate real-time kinetics of protoporphyrin IX (PpIX) in LGG based on hyperspectral fluorescence-based measurements and identify factors that predict fluorescence. METHODS: Patients with grade II gliomas and imaging from which HGGs could not be completely ruled out received 5-ALA at 20 mg/kg body weight 4 hours prior to surgery. Fluorescence intensity (FI) and PpIX concentration (CPpIX) were measured in tumor tissue utilizing a hyperspectral camera. Apparent diffusion coefficient (ADC)-based tumor cell density, Ki-67/MIB-1 index, chromosomal 1p/19q codeletion, and 18F-fluoroethyl-l-tyrosine (18F-FET) PET values and their role for predicting fluorescence were evaluated. RESULTS: Eighty-one biopsies from 25 patients were included. Tissues with fluorescence demonstrated FI and CPpIX maxima between 7 and 8 hours after administration. When visible fluorescence was observed, peaks of FI and CPpIX were observed within this 7- to 8-hour time frame, regardless of any MRI gadolinium contrast enhancement. Gadolinium enhancement (p = 0.008), Ki-67/MIB-1 index (p < 0.001), 18F-FET PET uptake ratio (p = 0.004), and ADC-based tumor cellularity (p = 0.017) significantly differed between fluorescing and nonfluorescing tissue, but not 1p/19q codeletions. Logistic regression demonstrated that 18F-FET PET uptake and Ki-67/MIB-1 index were independently related to fluorescence. CONCLUSIONS: This study reports a fluorescence-based assessment of CPpIX in human LGG tissues related to 18F-FET PET uptake and Ki-67/MIB-1. As in HGGs, fluorescence in LGGs peaked between 7 and 8 hours after 5-ALA application, which has consequences for the timing of administration.

Pedicle Subtraction Osteotomy for Deformity Correction in the Upper Cervical Spine: A Technical Note.

BACKGROUND: Kyphosis is the most common deformity of the cervical spine leading to development of severe disabilities. In case of fused kyphosis, surgical treatment can be demanding and often requires multiple-step procedures for adequate correction. We present a technique of single-stage pedicle subtraction osteotomy (PSO) of C3 to treat a patient with fused kyphosis of C2 and C3 causing spinal stenosis with subsequent myelopathy. METHODS: A 53-year-old man presented with progressive myelopathy not able to walk with 6/18 points on the modified Japanese Orthopedic Association scale. Horizontal gaze was lost due to cervical kyphosis. Magnetic resonance imaging (MRI) revealed a cervical kyphosis causing stenosis, cord compression, and kinking; computed tomography (CT) showed substantial anterior and posterior fusion of C2 and C3. RESULTS: Surgery included decompression via laminectomy of C2 to C6 in combination with PSO of C3 and additional dorsal instrumentation of C2 to C6. Cervical spinal alignment was corrected, as the C2-C4 Cobb angle was reduced from 48.9 to 20.6 degrees. Horizontal gaze was restored. Postoperative MRI demonstrated full decompression of the cord without kinking of the vertebral arteries. No complications were noted. The patient recovered well with restoration of his ability to walk. CONCLUSION: Single-stage pedicle subtraction closing wedge osteotomy in the upper cervical spine, although a demanding surgical procedure, is an alternative treatment option in selected cases of fused and severe cervical kyphosis. In contrast to multiple-step approaches, the single-stage procedure could reduce operating time and may thus decrease complications.

Applicability of contemporary quality indicators in vestibular surgery-do they accurately measure tumor inherent postoperative complications of vestibular schwannomas?

BACKGROUND: Due to rising costs in health care delivery, reimbursement decisions have progressively been based on quality measures. Such quality indicators have been developed for neurosurgical procedures, collectively. We aimed to evaluate their applicability in patients that underwent surgery for vestibular schwannoma and to identify potential new disease-specific quality indicators. METHODS: One hundred and three patients operated due to vestibular schwannoma were subject to analysis. The primary outcomes of interest were 30-day and 90-day reoperation, readmission, mortality, nosocomial infection and surgical site infection (SSI) rates, postoperative cerebral spinal fluid (CSF) leak, facial, and hearing function. The secondary aim was the identification of prognostic factors for the mentioned primary outcomes. RESULTS: Thirty-day (90-days) outcomes in terms of reoperation were 10.7% (14.6%), readmission 9.7% (13.6%), mortality 1% (1%), nosocomial infection 5.8%, and SSI 1% (1%). A 30- versus 90-day outcome in terms of CSF leak were 6.8% vs. 10.7%, new facial nerve palsy 16.5% vs. 6.1%. Hearing impairment from serviceable to non-serviceable hearing was 6.8% at both 30- and 90-day outcome. The degree of tumor extension has a significant impact on reoperation (p < 0.001), infection (p = 0.015), postoperative hemorrhage (p < 0.001), and postoperative hearing loss (p = 0.026). CONCLUSIONS: Our data demonstrate the importance of entity-specific quality measurements being applied even after 30 days. We identified the occurrence of a CSF leak within 90 days postoperatively, new persistent facial nerve palsy still present 90 days postoperatively, and persisting postoperative hearing impairment to non-serviceable hearing as potential new quality measurement variables for patients undergoing surgery for vestibular schwannoma.

The applicability of established clinical and histopathological risk factors for tumor recurrence during long-term postoperative care in meningioma patients.

Risk factors to predict late-onset tumor recurrence in meningioma patients are urgently needed to schedule control intervals during long-term follow-up. We therefore analyzed the value of established risk factors for postoperative meningioma recurrence for the prediction of long-term prognosis. Correlations of clinical and histopathological variables with tumor relapse after 3, 5, and 10 years following microsurgery were analyzed in uni- and multivariate analyses, and compared to findings in the entire cohort. In the entire cohort (N = 1218), skull base location (HR: 1.51, 95%CI 1.05-2.16; p = .026), Simpson ≥ IV resections (HR: 2.41, 95%CI 1.52-3.84; p < .001), high-grade histology (HR: 3.70, 95%CI 2.50-5.47; p < .001), and male gender (HR: 1.46, 95%CI 1.01-2.11; p = .042) were independent risk factors for recurrence. Skull base location (HR: 1.92, 95%CI 1.17-3.17; p = .010 and HR: 2.02, 95%CI 1.04-3.95; p = .038) and high-grade histology (HR: 1.87, 95%CI 1.04-3.38; p = .038 and HR: 2.29, 95%CI 1.07-4.01; p = .034) but not subtotal resection (HR: 1.53, 95%CI .68-3.45; p = .303 and HR: 1.75, 95%CI .52-5.96; p = .369) remained correlated with recurrence after a recurrence-free follow-up of ≥ 3 and ≥ 5 years, respectively. Postoperative tumor volume was related with recurrence in general (p < .001) but not beyond a follow-up of ≥ 3 years (p > .05). In 147 patients with a follow-up of ≥ 10 years, ten recurrences occurred and were not correlated with any of the analyzed variables. Skull base tumor location and high-grade histology but not the extent of resection should be considered when scheduling the long-term follow-up after meningioma surgery. Recurrences ≥ 10 years after surgery are rare, and predictors are lacking.

Load-Bearing Capacity and Design Advantages of a Custom-Made, Thin Pure-Titanium Cranioplasty (CranioTop).

BACKGROUND: Adequate and stable coverage of cranial contour and continuity defects of any origin is a common challenge in neurosurgical clinics. This study presents the results of investigations concerning the mechanical load-bearing capacity and design advantages of custom-made implants made from a thin, pure-titanium sheet (CranioTop) (CLinstruments, Attendorn, Germany) for covering complex cranial defects. METHODS: In 9 test series, the stability of three differently shaped and sized thin titanium sheet implants was tested using vertical, uniaxial compression with 3 different compression stamps, to investigate the behaviour of these implants in relation to punctiform as well as planar forces. RESULTS: All 9 model implants showed elastic behavior in the synchronously recorded force/displacement diagrams at an impression of up to 2 mm. The forces at 2 mm deformation were between 170.1 and 702.7 Newton. CONCLUSION: Cranioplasty using CranioTop is a stable procedure for covering skull defects, even those of large dimensions. An added advantage is the significant reduction in effort required to prepare the area of the bone margins compared to other current techniques of cranioplasty.