3-T MR-guided focused ultrasound thalamotomy for tremor in patients with a cardiac pacemaker: case series and review of the literature.

MR-guided focused ultrasound (MRgFUS) has proven its efficacy and safety for the treatment of essential tremor (ET) and/or Parkinson's disease (PD). However, having a cardiac pacemaker has been considered an exclusion criterion for the use of MRgFUS. Only 2 patients with a cardiac pacemaker treated with MRgFUS have been previously reported, both treated using 1.5-T MRI. In this paper, the authors present their experience performing 3-T MRgFUS thalamotomy in 4 patients with an implanted cardiac pacemaker. Treatments were uneventful regarding complications or severe side effects. MRgFUS using 3-T MRI was found to be an efficient and safe treatment for ET and/or PD in patients with an MRI-compatible pacemaker.

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.

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.

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.

Iatrogenic Intracranial Aneurysm After External Ventricular Drain Placement: Traumatic or Mycotic Origin? Case Report and Literature Review.

BACKGROUND: Intracranial iatrogenic aneurysms (IIAs) developing after external ventricular drain (EVD) placement or removal have been only rarely reported. Most of these reports assumed a traumatic etiology; however, some have demonstrated an inflammatory origin. We have presented the case of an IIA that developed after an EVD had been inserted to treat acute hydrocephalus secondary to a ruptured arteriovenous malformation. We also performed a literature review and discussed how these IIAs might have an inflammatory rather than a traumatic etiology and how they might lie behind some of the cases of idiopathic hemorrhage observed after EVD manipulation. CASE DESCRIPTION: A 48-year-old woman had presented with acute hydrocephalus secondary to bleeding from a vermian arteriovenous malformation. The EVD inserted for hydrocephalus management required several revisions because of malfunction. Four weeks later, a diagnostic arteriogram had incidentally revealed the existence of a 5-mm aneurysm in an anterior branch of the right callosomarginal artery, coincidental to the EVD trajectory. The patient underwent emergent endovascular treatment of the aneurysm, with complete occlusion and no complications deriving from the procedure. CONCLUSIONS: IIAs associated with EVD placement or removal have been described as a rare complication of the procedure. Despite the scarce number of cases reported and the lack of histological examinations, common features such as a distal location, an incidental diagnosis, and a benign clinical course might suggest a mycotic or inflammatory origin rather than a traumatic etiology. Considering the high volume of EVDs placed annually, this complication might be more frequent than reported. Further studies investigating the association of risk factors for inflammatory aneurysms and hemorrhage incidence after EVD could provide information on this intriguing topic.

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.