Citations

OBJECTIVE Core outcome sets (COSs) are needed to promote data consistency across studies as well as data synthesis and comparability. The aim of the current study was to use a modified Delphi process to develop a COS for lateral femoral cutaneous neuropathy (LFCN), hereafter COS-LFCN. METHODS A 5-stage approach was used to develop the COS-LFCN: 1) consortium development, 2) literature review to identify potential outcome measures, 3) Delphi survey to develop consensus on outcomes for inclusion, 4) Delphi survey to develop definitions, and 5) consensus meeting to finalize the COS and definitions. This study followed the Core Outcome Set - STAndards for Development, (COS-STAD) recommendations. RESULTS The Core Outcomes in Nerve Surgery (COINS) Consortium comprised 25 participants, all neurological surgeons, representing 14 countries. The final COS-LFCN consisted of 41 factors and outcomes covering domains of demographics, diagnostics, patient-reported outcomes, motor/sensory outcomes, and complications. Appropriate instruments, methods of testing, and definitions were set. The consensus minimum duration of follow-up was 12 months, with the consensus optimal time points for assessment being preoperatively and 3, 6, and 12 months postoperatively. CONCLUSIONS The COINS Consortium developed a consensus COS for LFCN and provided definitions, methods of implementation, and time points for assessment. The COS-LFCN should serve as the minimum data to be collected in all future neurosurgical studies on LFCN. Incorporation of this COS will help improve consistency in reporting, data synthesis and comparability, and minimize outcome reporting bias.

OBJECTIVE Deep brain stimulation (DBS) is emerging as an additional surgical option for refractory, multifocal epilepsy. Four-lead DBS systems can be used when seizure onset is poorly localized, generalized, or involves multiple targetable circuits. The goal of this study was to assess preliminary outcomes and complication rates in 4-lead DBS systems for treating epilepsy. METHODS A consecutive series of 32 patients with 4-lead DBS implants who had at least 6 months of follow-up was reviewed, and demographics, outcomes, and complications were abstracted. RESULTS Thirty-two patients implanted with 4 DBS leads (including off-label use) were included. The median age at surgery was 28.5 years, the median age at epilepsy diagnosis was 7.5 years, and 18 patients (56%) were women. The median epilepsy duration prior to implantation was 21 years. The most common seizure localization was frontotemporal (53%), followed by generalized (28%) and parietoccipital (13%). Prior vagus nerve stimulation had been trialed in 20 patients (63%), and an invasive stereotactic EEG recording was performed in 17 patients (59%). Eight patients had prior epilepsy surgery (25%). DBS targets included the anterior thalamic nucleus in combination with the centromedian thalamic nucleus, hippocampus, pulvinar nucleus, cingulate, insula, and globus pallidus. The median surgical duration was 5 hours 22 minutes, with a median operating room time of 8 hours 21 minutes. The median postoperative follow-up was 27 (interquartile range 17–41) months. Three patients experienced transient neurological deficits and 2 patients required intraoperative lead repositioning. There were no infections or hemorrhages. Most patients benefited from stimulation (22% Engel class I, 22% class II, 28% class III, and 28% class IV). The median patient-reported seizure reduction rate was 70%, with a responder rate of 72%. One patient elected to have the system explanted. CONCLUSIONS Four-lead DBS is safe and can achieve meaningful improvement in challenging cases of multifocal epilepsy with a low complication rate.

OBJECTIVE This study evaluated the utility of routine versus symptom-driven MRI to detect hemorrhage in patients with sporadic cerebral cavernous malformations (CCMs) and assessed associated radiographic changes at the first clinical follow-up. METHODS The authors analyzed a prospective, single-center cohort of patients with sporadic, brain-only CCMs who underwent at least 1 follow-up MRI after diagnosis. Clinical and radiological data were obtained from a longitudinal registry. Follow-up findings included lesion growth (≥ 3 mm), changes in Zabramski classification, persistent T1-weighted hyperintensity, edema, and hemorrhage. MRI indications were categorized as routine surveillance or symptom driven (e.g., new or worsening focal neurological deficit [FND], headache, or seizure). Univariate and multivariate analyses were performed to assess predictors of symptomatic hemmorhage (SH). RESULTS Of 236 included patients, 59.3% were female, and 39.8% initially presented with SH. At the first follow-up MRI, radiographic hemorrhage was observed in 13 of 68 patients (19.1%) imaged for new or worsening neurological symptoms (FND, headaches, or seizures), compared to 2 of 168 patients (1.2%) during routine or non–CCM-related surveillance. Among these 168 patients, 17 (10.1%) showed radiological progression—including lesion growth (n = 11 [6.5%]), a change to a more aggressive Zabramski type (n = 10 [6.0%]), and radiological evidence of acute hemorrhage (n = 2 [1.2%]). Most of these events (88.2%) occurred within 2 years. SH was characterized by lesion growth, moderate-to-severe T1-hyperintensity, and edema. Baseline lesion size and location did not predict hemorrhage. New or worsening FND predicted hemorrhage, whereas seizure and headache alone did not. In the multivariate analysis, only the presence of new or worsening FND remained independently associated with hemorrhage (OR 13.73, p < 0.001). CONCLUSIONS In patients with known CCM, MRI should be performed in case of new or worsening FND, as this was the strongest predictor of hemorrhage. Routine surveillance had limited diagnostic yield in asymptomatic patients but may be appropriate in select cases.

OBJECTIVE The aim of this study was to determine predictors of the minimum clinically important difference (MCID) in the Neck Disability Index (NDI) following cervical spinal deformity surgery. METHODS A retrospective review was performed of a prospective, multicenter adult cervical spinal deformity database. All patients had baseline and 1-year NDI scores. Patients met MCID with an improvement of NDI by 7 points between baseline and 1 year, as previously established. Baseline demographics, comorbidities, and both baseline and 1-year spinopelvic parameters were evaluated for statistical significance in a univariate logistic regression analysis. Significant variables, in addition to baseline NDI, were analyzed in a multivariable logistic regression model by backward selection with Akaike information criterion minimization. RESULTS A total of 122 patients were included with a median age of 62 (IQR 56, 69) years; 62% of patients were female. Of the 122 patients, 72 (59%) achieved NDI MCID at 1 year. Predictors of achieving MCID on univariate analysis included a lower Charlson Comorbidity Index (CCI) total score (OR 0.70, p = 0.03), depression as a comorbidity (OR 2.9, p = 0.02), lower C2 tilt at the 1-year follow-up (OR 0.92, p = 0.02), and a greater difference between 1-year postoperative C2–7 sagittal vertical axis (SVA) and preoperative C2–7 SVA (OR 0.98, p = 0.0495). On multivariable logistic regression analysis, predictors of achieving MCID included a lower CCI (OR 0.62, p = 0.03), depression as a comorbidity (OR 3.1, p = 0.059), a greater change in C2–7 SVA at the 1-year follow-up compared with baseline (OR 0.97, p = 0.055), and baseline NDI (OR 1.02, p = 0.24) with an area under the curve of 0.74. CONCLUSIONS The best-fit multivariable model included higher baseline NDI, a greater change in C2–7 SVA, patient-reported baseline depression, and lower CCI as important factors in predicting NDI MCID.

OBJECTIVE This study aimed to determine minimum clinically important difference (MCID) values for dysphagia using the Eating Assessment Tool-10 (EAT-10) in patients undergoing anterior cervical surgery, focusing on early dissatisfaction and later satisfaction thresholds to guide clinical decisions. METHODS Data were prospectively collected from patients undergoing anterior cervical surgery across three institutions from 2016 to 2024. Dysphagia severity was assessed preoperatively and at various postoperative stages up to 1 year using EAT-10. The inverse probability of treatment weighting was used to control for confounding variables. The retrospective study of patient data employed two analytical phases: the first phase examined the relationship between dissatisfaction at 3 months (indicated by a North American Spine Society satisfaction score > 2) and changes in EAT-10 scores from baseline to peak (i.e., worst) postoperative scores; the second phase focused on recovery, comparing changes in EAT-10 scores from peak postoperative scores to 12 months against satisfaction (score < 2) at 12 months. RESULTS The mean ± SD baseline EAT-10 score for the 1463 patients included in the study was 1.5 ± 4.7 and the mean peak score was 5.2 ± 7.4. The patients underwent anterior cervical discectomy and fusion (90%), arthroplasty (6%), or corpectomy (4%); a hybrid procedure was used in 1%. The phase 1 analysis indicated that a 4-point increase in EAT-10 score was a threshold for significant postoperative dissatisfaction in those without baseline dysphagia, with much higher thresholds observed in patients with any baseline dysphagia. In phase 2, among patients with baseline EAT-10 scores < 3 who experienced an increase to EAT-10 score ≥ 8 postoperatively, a subsequent decrease of 9 points by 12 months was necessary to report satisfaction. For patients with baseline scores 3–8 whose postoperative scores rose to ≥ 8, a subsequent decrease of 15 points was necessary for satisfaction. Patients with initial scores of ≥ 8 who did not improve to < 3 immediately after surgery required further reductions of 2–11 points to reach satisfaction. CONCLUSIONS The MCID thresholds from this study provide crucial benchmarks for assessing dysphagia changes after anterior cervical surgery, allowing tailored interventions. Patients with baseline dysphagia are less likely to experience early dissatisfaction, and high peak scores negatively impact long-term satisfaction. These findings emphasize the importance of proactive dysphagia management to enhance patient outcomes.

BACKGROUND Ulnar neuropathy at Guyon’s canal is rare, but when it occurs, it is frequently due to underlying masses, including extraneural and intraneural ganglion cysts, as well as adventitial cysts. The pathogenesis of these cysts, especially at a rare site, remains controversial. The articular theory, which is gaining popularity, posits that a joint connection via a nerve (or vascular) branch to a neighboring joint represents the pathway for their formation and propagation. OBSERVATIONS A recently published case of a patient with an ulnar intraneural ganglion at the wrist with a series of postoperative cystic recurrences was reevaluated, as it challenged the articular theory. No discrete articular branch had been identified on imaging or at surgery. Serial MR images were reinterpreted, which revealed that the original intraneural cyst was treated; new sequential cysts—an adventitial cyst and then a soft tissue ganglion—developed, all arising from the same wrist joint. LESSONS This case strengthens the principles of the articular theory for intraneural ganglion, adventitial, and soft tissue ganglion cysts. A small wrist connection from the ulnar intraneural ganglion was unrecognized and untreated. Scarring disrupted the original nerve pathway and pressure dynamics. New cysts developed through neighboring joint capsular rents along different pathways into other “compartments” (vessel or soft tissues). https://thejns.org/doi/10.3171/CASE25618

BACKGROUND Recently, the distribution of subparaneurial ganglion cysts involving the common peroneal and tibial nerves was described based on MRI analysis. Crossover in extreme cases was observed at the sciatic bifurcation through a mechanism comparable to a geyser, enabled by fenestrations in the epi- and paraneurium at the level of the bifurcation. The goal of this study was to investigate whether the geyser theory for crossover holds for other locations. OBSERVATIONS The authors’ prospectively maintained database of > 1100 cases of intraneural ganglion cysts in the world’s literature was queried for the existence of subparaneurial ganglion cysts at locations other than the knee. A previously unrecognized case involving the ulnar nerve originating from the elbow joint was found. Reinterpretation of the patient’s MRI studies showed circumferential subparaneurial distribution of a cyst over a long distance. Based on their previously reported geyser theory, the authors wondered if crossover had occurred at the level of the medial cord. A fenestration in the epi- and paraneurium at this level was confirmed on histological analysis of a normal cadaveric specimen. LESSONS This illustrative case shows that the geyser theory also holds in other locations. Surgical treatment of these subparaneurial cysts still follows the principles of the unified articular theory. https://thejns.org/doi/10.3171/CASE25671

Background: Venous air embolism (VAE) is a potentially catastrophic complication during neurosurgical procedures, particularly in the sitting position. As practices vary widely, we conducted a survey to describe the global practice patterns for intraoperative detection and management of VAE. Methods: Following institutional review board (IRB) approval, we conducted a cross-sectional study using a 48-question online survey that was distributed via a snowball sampling approach, initially to the Society of Neuroscience in Anesthesiology and Critical Care (SNACC) community and subsequently to international collaborators. Descriptive statistics summarized responses, and proportional comparisons between high-income and low- and middle-income country respondents were assessed using a χ 2 or the Fisher exact tests, as appropriate. Results: Of 307 responses, 297 were analyzed, representing 40 countries. Survey response rate was 25% among SNACC members. End-tidal carbon dioxide (EtCO 2 ) monitoring was the most frequently reported VAE monitoring modality, particularly for sitting craniotomies. Common barriers to implementing advanced monitoring included limited equipment availability and a lack of a transesophageal echocardiography (TEE) specialist. Decision-making for cases at VAE risk relied on team consensus (62%), review articles and primary literature (48%), and institutional protocols (42%). Among respondents, 89% expressed interest in consensus guidelines for VAE management. Conclusions: There is substantial global variability in both the preparation for and management of VAE during neurosurgical procedures. EtCO 2 is the preferred monitoring approach in routine practice, as resource limitations prevent the broader adoption of more sensitive techniques, such as TEE. The high interest in consensus guidelines underscores an opportunity for professional societies to standardize approaches and improve patient safety.

ABSTRACT Background In the United States, metoclopramide is the only medication approved for gastroparesis. There is a need to reappraise the main considerations involved in the approval of pharmacological treatments of gastroparesis. Objectives and Methods We conducted a literature review to address issues that might impact the approval of medications for gastroparesis. We appraised the epidemiology, clinical presentations, variations in diagnostic tests, and their thresholds for identification of gastroparesis. Based on the review, we proposed trial designs for proof of efficacy and safety of novel medications for gastroparesis. Results Based on epidemiological studies, the age‐adjusted prevalence in US population is 152,005 for all categories (definite, probable and possible) of gastroparesis. The major symptoms of gastroparesis are nausea, vomiting, early satiety and postprandial fullness and may lead to hospitalisation or emergency department visits. It is essential to appraise gastric emptying with a solid meal over at least 3 h using scintigraphy or a stable isotope breath test. Diagnostic thresholds have been established for these diagnostic tests and at present, reproducibility, normative data, and coefficient of variation are well established for the 320‐kcal real egg solid meal. Based on published guidelines on clinical efficacy of medications used in gastroparesis, we propose targeting the gastroparesis symptom subscales, such as nausea and vomiting, with pharmacological agents specifically directed at their causative mechanisms rather than targeting the underlying dysmotility. Conclusion The evidence documented here justifies consideration of gastroparesis as an orphan disease, as well as an innovative approach to supplement the regulatory bodies' recommendations and guidance to industry. We propose treatment trials of 4‐weeks duration and considering the use of specific symptoms of gastroparesis as clinical endpoints based on a pharmaceutical agent's mechanism of action, rather than using a total gastroparesis symptom score. Such an approach would include evidence of safety and efficacy of new medications targeting gastroparesis subscales, and approval for marketing would be based on the symptoms specifically ameliorated in robust trials.