Intraoperative ultrasound and magnetic resonance comparative analysis in brain tumor surgery: a valuable tool to flatten ultrasound's learning curve.

BACKGROUND: Intraoperative ultrasound (IOUS) is a profitable tool for neurosurgical procedures' assistance, especially in neuro-oncology. It is a rapid, ergonomic and reproducible technique. However, its known handicap is a steep learning curve for neurosurgeons. Here, we describe an interesting postoperative analysis that provides extra feedback after surgery, accelerating the learning process. METHOD: We conducted a descriptive retrospective unicenter study including patients operated from intra-axial brain tumors using neuronavigation (Curve, Brainlab) and IOUS (BK-5000, BK medical) guidance. All patients had preoperative Magnetic Resonance Imaging (MRI) prior to tumor resection. During surgery, 3D neuronavigated IOUS studies (n3DUS) were obtained through craniotomy N13C5 transducer's integration to the neuronavigation system. At least two n3DUS studies were obtained: prior to tumor resection and at the resection conclusion. A postoperative MRI was performed within 48 h. MRI and n3DUS studies were posteriorly fused and analyzed with Elements (Brainlab) planning software, permitting two comparative analyses: preoperative MRI compared to pre-resection n3DUS and postoperative MRI to post-resection n3DUS. Cases with incomplete MRI or n3DUS studies were withdrawn from the study. RESULTS: From April 2022 to March 2024, 73 patients were operated assisted by IOUS. From them, 39 were included in the study. Analyses comparing preoperative MRI and pre-resection n3DUS showed great concordance of tumor volume (p < 0,001) between both modalities. Analysis comparing postoperative MRI and post-resection n3DUS also showed good concordance in residual tumor volume (RTV) in cases where gross total resection (GTR) was not achieved (p < 0,001). In two cases, RTV detected on MRI that was not detected intra-operatively with IOUS could be reviewed in detail to recheck its appearance. CONCLUSIONS: Post-operative comparative analyses between IOUS and MRI is a valuable tool for novel ultrasound users, as it enhances the amount of feedback provided by cases and could accelerate the learning process, flattening this technique's learning curve.

Effectiveness and safety of Tachosil® as a ventricular sealant: an observational cohort study.

PURPOSE: Surgery close to or in contact with the ventricular system is challenging due to the complications. We sought to evaluate the effectiveness and safety of TachoSil® as a ventricular sealant in preventing complications after cranial surgery with an open ventricular system (OVS). METHODS: This is a single-center and prospective cohort study We included patients who underwent elective surgery for supratentorial craniotomy and periventricular pathology between December 2020 and November 2023. We registered surgical complications arising from CSF dynamics (such as percutaneous cerebrospinal fluid (CSF) leakage, hydrocephalus, pseudomeningocele), infections, and other complications (postsurgical hematoma) adverse drug reactions (ADRs), reintervention or hospital readmission up to 90 days after surgery. RESULTS: Forty interventions were performed on 39 patients, whose median age was 56 years. Eleven patients (28.2%) had antecedents of previous surgery in the same location, 5 (12.8%) had previously received radiotherapy and chemotherapy, and 11 (28.2%) were smokers. Twenty-four patients (60%) underwent surgery for high-grade glioma, 8 (20%) for low-grade gliomas, 6 (15%) for metastasis and 2 (5%) for meningioma. Throughout the study and up to 90 days after surgery, none of the patients presented an ADR. Only 2 patients (5%) presented with a surgery complications derived from ventricular opening (one patient with a percutaneous CSF leakage and one patients with external hydrocephalus). Both patients resolved with a ventriculoperitoneal shunt. CONCLUSIONS: TachoSil® is a dural sealant that can be used safely and effectively intraparenchymally in patients whose surgery involves a ventricular opening. Only 5% of treated patients presented complications arising from CSF hydrodynamics. No patients had pseudomeningocele, infections or complications related to the use of this sealant. To confirm these positive results, randomized and comparative clinical trials assessing the efficacy of TachoSil® in patients after cranial surgery with an OVS are essential. TRIAL REGISTRATION NUMBER AND DATE OF REGISTRATION: This study was registered in the Clinical Trials.gov (NCT05717335). Date May 1st, 2022.

Delayed hemorrhage after pediatric stereo-electroencephalography: delayed occurrence or delayed diagnosis?

BACKGROUND: Stereo-electroencephalography (SEEG) is a well-known invasive diagnostic method for drug-resistant epilepsy (DRE). Its rate of complications is relatively low, being the intracranial hemorrhage (ICH) the most relevant. Most centers perform immediate imaging studies after SEEG to rule out complications. However, delayed intracranial hemorrhages (DIH) can occur despite normal imaging studies in the immediate postoperative period. METHODS: We performed a retrospective review of DRE pediatric patients operated on SEEG between April 2016 and December 2020 in our institution. After implantation, an immediate postoperative CT was performed to check electrode placement and rule out acute complications. An additional MRI was performed 24 h after surgery. We collected all postoperative hemorrhages and considered them as major or minor according to Wellmer´s classification. RESULTS: Overall, 25 DRE patients were operated on SEEG with 316 electrodes implanted. Three ICHs were diagnosed on postoperative imaging. Two of them were asymptomatic requiring no treatment, while the other needed surgical evacuation after clinical worsening. The total risk of hemorrhage per procedure was 12%, but just one third of them were clinically relevant. Two hemorrhages were not visible on immediate postoperative CT, being incidentally diagnosed in the 24 h MRI. We recorded them as DIH and are reported in detail. CONCLUSION: Few reports of DIH after SEEG exist in the literature. It remains unclear whether these cases are late occurring hemorrhages or immediate postoperative hemorrhages undiagnosed on initial imaging. According to our findings, we recommend to perform additional late postoperative imaging to diagnose these cases and manage them accurately.

Validation of shunt dependency prediction scores after aneurysmal spontaneous subarachnoid hemorrhage.

BACKGROUND: Currently available scores for predicting shunt dependency after aneurysmal spontaneous subarachnoid hemorrhage (aSAH) are limited and not widely accepted. The key purpose of this study was to validate a recently created score for shunt dependency in aSAH (SDASH) in an independent population of aSAH patients. We compared this new SDASH score based on a combination of the Hunt and Hess grade, Barrow Neurological Institute (BNI) score, and the presence or not of acute hydrocephalus with other published predictive scores. METHODS: The SDASH score, Hijdra score, BNI grading system, chronic hydrocephalus ensuing from SAH score (CHESS), Graeb score, and modified Graeb score (mGS) were calculated for a cohort of aSAH patients. Logistic regression analysis was used to determine the reliability of the SDASH score, and the area under the curve (AUC) of the receiver operating characteristics (ROC) curve was used to assess the discriminative ability of the model. RESULTS: In 214 patients with aSAH, 40 (18.7%) developed shunt-dependent hydrocephalus (SDHC). The AUC for the SDASH score was 0.816. The SDASH score reliably predicted SDHC in aSAH (odds ratio: 2.93, 95% CI: 1.99-4.31; p < 0.001) with no statistically significant differences being found between the SDASH score and the CHESS score (AUC: 0.816), radiological-based Graeb score (AUC: 0.742), or modified Graeb score (AUC: 0.741). However, the Hijdra score (AUC: 0.673) and BNI grading system (AUC: 0.616) showed lower predictive values than the SDASH score. CONCLUSIONS: Our findings support the ability of the SDASH score to predict shunt dependency after SAH in a population independent to that used to develop the score. The SDASH score may aid in the early management of hydrocephalus in aSAH, and it does not differ greatly from other predictive scores.

Growth prediction in asymptomatic meningiomas: the utility of the AIMSS score.

BACKGROUND: Management of asymptomatic meningiomas represents a challenge due to the absence of a solid consensus on which is the best management strategy. There are various known factors predicting meningiomas growth risk. However, the Asian Intracranial Meningioma Scoring System (AIMSS) is the only described score to quantify such risk thus emerging as a potential tool for management decisions. This study aims to validate this score on our series of asymptomatic meningiomas. METHOD: We performed a retrospective review of asymptomatic meningiomas diagnosed at our institution between January 2008 and October 2016 and followed by an annual cerebral Magnetic Resonance Imaging (MRI). For each lesion, the AIMSS score was calculated thus classifying them in low (0-2), intermediate (3-6) or high risk (7-11) of rapid growth (>2cm3/year). We investigated the correlation between the expected Average Growth Rate (AGR) according to the score and the one obtained in our study. The mean growth velocity over the different risk groups was also compared. RESULTS: Overall, 69 asymptomatic meningiomas found incidentally in 46 patients were included in the study; 31 were assigned to the low-risk group, 34 to the intermediate-risk group and 4 to the high-risk group. Attending to the AGR, 0% showed rapid growth in the low-risk group, 12% in the intermediate-risk group, and 25% in the high-risk group. The mean growth velocity showed a significant difference over the different risk groups (p < 0,001). CONCLUSIONS: According to our finding, the AIMSS score is a valid tool to estimate the risk of rapid growth of asymptomatic meningiomas. It is especially useful distinguishing between low- and intermediate-risk meningiomas. This feature would allow physicians to adjust the periodicity of radiological and clinical controls. Adding more known risk factors of rapid growth to the score might improve its predictive capabilities with the high-risk group.

Dural Venous Sinus Variations in Idiopathic Subarachnoid Hemorrhage: A New Indicator of the Venous Origin with Diagnostic Usefulness?

OBJECTIVE: Venous hypertension associated with a primitive basal vein of Rosenthal (BVR) has been noted as the most likely cause of idiopathic subarachnoid hemorrhage (iSAH). Other types of venous drainage variations have been scarcely studied but may further explain the cases not associated with a BVR anomaly. Our aim was to investigate if dural venous sinus (DVS) anomalies are related with iSAH. METHODS: A total of 76 patients diagnosed with iSAH were identified from a prospectively maintained database and their angiographic findings compared with 76 patients diagnosed with aneurysmal subarachnoid hemorrhage. RESULTS: On top of the BVR variations, our data showed a higher prevalence of transverse sinus hypoplasia (47.4% vs. 28.9%; P = 0.019), superior petrosal sinus hypoplasia (32.9% vs. 13.2%; P = 0.003), and clival plexus hyperplasia (65.8% vs. 43.4%; P = 0.005) in patients with iSAH. Analyzing by total number of angiograms, the iSAH group showed also a higher prevalence of inferior petrosal sinus hyperplasia (36.2% vs. 25%; P = 0.003). Of the patients with iSAH without a primitive BVR, 84% harbored ≥1 perimesencephalic DVS variation and the overall number of venous drainage variations was significantly higher in patients with iSAH. CONCLUSIONS: In addition to the well-documented BVR anomalies, there seems to be a significant relationship of other DVS variations in patients with iSAH. Transverse sinus hypoplasia, superior petrosal sinus hypoplasia, inferior petrosal sinus hyperplasia, and clival plexus hyperplasia were significantly more frequent in patients with iSAH. The presence of ≥3 of those variations would increase the suspicion of a nonaneurysmatic subarachnoid hemorrhage and could help avoid a second angiogram.

Amateur Endurance Athletes: At Higher Risk of Suffering Dural Arteriovenous Fistulas? Report of 3 Cases.

BACKGROUND: The present study aims to draw attention to the fact that endurance sport could be a risk factor for dural arteriovenous fistula (DAVF) development. DAVFs have been correlated with acquired dural venous sinus anomalies owing to trauma, infection, neoplasia, or other classic risk thrombogenic factors. Here we report 3 cases of intracranial DAVF in young healthy patients who had no known thrombogenic risk factors other than amateur intensive sports practice. CASE DESCRIPTION: Three young healthy individuals not fitting into the classical clinical picture of a DAVF patient presented to our institution. One was a 40-year-old man with an acute subdural hematoma secondary to an ethmoidal DAVF. Another 41-year-old man presented with a cerebellar hematoma due to a tentorial DAVF. A third 41-year-old man presented with numbness of his right arm in relationship to a superior sagittal sinus DAVF. None of them had a relevant medical history. All the usual thrombogenic risk factors for DAVF development were ruled out. Interestingly, the 3 patients had outstanding training and practice routines for endurance sports. CONCLUSIONS: Dehydration, microfractures, muscular contractures, low heart rate, long distance travel, and high altitudes are all well documented thrombogenic risk factors affecting endurance sports amateur athletes and might represent a plausible mechanism for the development of DAVF. Despite its limitations, to our knowledge, this is the first work suggesting a possible link between such sport practice and DAVF development. Further prospective research from larger dedicated vascular centers might shed further light on this hypothetic but intriguing link.