Citations

Abstract Hypoparathyroidism is an endocrine disease caused by insufficient levels of PTH, which acts directly on bone and kidney and indirectly on the intestine to regulate calcium and phosphate balance. In clinical trials, palopegteriparatide (TransCon PTH) treatment enabled independence from conventional therapy (no active vitamin D, ≤600 mg/d calcium) and maintained serum biochemistries within normal ranges. The current analyses describe patterns of change in BMD, serum bone turnover markers, and serum and urine calcium in adults with chronic hypoparathyroidism treated with palopegteriparatide through 3 years of the PaTH Forward trial. Baseline BMD Z-scores for the LS, TH, FN, and 1/3 distal radius were above zero, indicating bone mass exceeding age-adjusted normative values. BMD decreased from these elevated baseline levels with palopegteriparatide treatment, with larger reductions during the first 26 weeks and modest declines thereafter. Mean BMD Z-scores at week 162 remained above zero for all 4 sites. Participants with lower baseline BMD (Z-scores below −1 and T-scores below −2.5) generally exhibited lesser declines in BMD versus those with higher baseline BMD. Palopegteriparatide treatment was associated with early increases in bone resorption (serum C-terminal telopeptide of type I collagen, CTx) and bone formation (serum procollagen type 1 N-terminal propeptide, P1NP) that peaked at weeks 12 and 26, respectively, followed by declines to levels moderately higher than baseline at week 162. Mean CTx and P1NP in the overall population and the subgroup of postmenopausal women were below their upper limits of normal from weeks 58-162. At week 162, mean serum and median urine calcium remained within normal ranges and 91% of participants were independent from conventional therapy. These results suggest that long-term palopegteriparatide therapy in adults with chronic hypoparathyroidism gradually returns the skeleton toward its natural state thereby enhancing the skeleton’s contribution to calcium homeostasis.

OBJECTIVE Brain metastases significantly impact neurocognitive function and overall survival. Stereotactic radiosurgery (SRS) is a cornerstone of treatment for patients with limited metastases and expected survival beyond 3 months. Despite current guidelines, up to 20% of patients with brain metastases undergoing SRS have been reported to die within 90 days. This study retrospectively evaluated prognostic factors associated with 90-day survival after SRS, aiming to improve patient selection. METHODS The authors retrospectively analyzed a cohort of 1546 patients who underwent Gamma Knife SRS for brain metastases at their institution between 2015 and 2023. One hundred seventy patients who survived less than 90 days after SRS were identified and case matched to 170 patients who survived over 90 days. Measured variables included patient demographic characteristics, tumor characteristics, treatment history, functional status, and control of the primary cancer. The authors modeled post-SRS 90-day survival using binomial and multivariate logistic regression. RESULTS Multivariate analysis highlighted Karnofsky Performance Score (KPS) < 70 (OR 17.4, p < 0.001), prior whole-brain radiation (OR 6, p = 0.004), and focal neurological deficits (OR 3.02, p = 0.003) as significant predictors of poor survival, whereas CNS progression before SRS (OR 0.22, p < 0.001) and control of systemic cancer (OR 0.556, p = 0.002) were associated with survival < 90 days. The predictive model demonstrated acceptable performance with an area under the curve (AUC) of 0.85, accuracy of 80%, sensitivity of 87%, and specificity of 71%. CONCLUSIONS Key predictors of 90-day survival after SRS for brain metastases include functional status (KPS), control of systemic cancer, CNS progression status, and focal neurological deficits. These findings are complementary factors that can assist in making decisions and SRS patient selection.

OBJECTIVE Cervical dystonia (CD) is the most common focal dystonia, characterized by abnormal head postures and pain, often refractory to botulinum toxin therapy. Selective peripheral denervation (SPD) remains a key surgical option, but long-term outcomes in large cohorts are underreported. The purpose of this study was to evaluate the long-term outcomes of SPD in patients with botulinum toxin–refractory CD, focusing on symptom severity, pain, and head posture improvement. METHODS This retrospective study included 160 adults (mean ± SD age 54 ± 12.0 years, 46% male) with refractory CD who underwent SPD at a single center by a single surgeon from January 2005 to July 2023. Outcomes were assessed using subjective clinical measures and the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS), which was calculated retrospectively from clinical records. The modified Bertrand technique involved selective denervation and myotomies tailored to each patient’s dystonic pattern. TWSTRS scores were analyzed at baseline, 3 months, 1 year, and final follow-up (mean ± SD 10.3 ± 9.0 months). Time to minimal clinically important difference (MCID) (≥ 12-point TWSTRS drop) was evaluated with covariate-adjusted Kaplan-Meier modeling (ever vs never revised, evaluated with the log-rank test) and a counting-process Cox model with revision as a time-dependent covariate. RESULTS Among 160 patients (mean follow-up duration 21.6 ± 35.6 months), TWSTRS improved by 73.5% at 3 months and 61.3% at last follow-up (p < 0.001). Median time to MCID was 3.0 months for never revised patients versus 22.0 months for ever revised patients (log-rank chi-square statistic = 19.09, p < 0.0001). In a time-dependent Cox model, revision surgery was significantly associated with higher likelihood of achieving MCID (HR 2.31, p < 0.005). Pain relief and improved head posture were reported in over 50% of patients. Complications were minimal, and recurrence was observed in 4.2% of cases. Outcomes were consistent with or exceeded those reported in the literature with either SPD or deep brain stimulation (DBS). CONCLUSIONS SPD is an effective and durable surgical option for refractory CD, significantly improving pain, posture, and quality of life. Although revision surgery delayed time to improvement, it significantly increased the likelihood of achieving meaningful clinical improvement. Overall efficacy aligns with the existing literature, reinforcing its role as a first-line surgical intervention. Further studies should explore strategies to enhance long-term outcomes and delineate the role of SPD relative to DBS.

OBJECTIVE The objective of this study was to describe the long-term efficacy of single-fraction stereotactic radiosurgery (SRS) for the primary treatment of sporadic vestibular schwannoma. METHODS Adult (≥ 18 years of age) patients with sporadic vestibular schwannoma who underwent SRS from 2000 through 2022 were included. RESULTS A total of 749 patients met inclusion criteria, the majority (n = 566, 76%) of whom had tumors extending into the cerebellopontine angle at SRS. The median patient age at SRS was 62 years, half (50%) of the patients were women, and 744 (99%) exhibited House-Brackmann grade I facial nerve function at SRS. A total of 42 patients experienced radiosurgical failure and underwent salvage treatment; the median duration of follow-up for the patients who did not undergo salvage treatment was 7.0 years. Overall tumor control rates (95% CI, number still at risk) at 1, 3, 5, 10, and 15 years after SRS were 100% (100%–100%, 718), 98% (97%–99%, 589), 96% (94%–97%, 464), 92% (90%–95%, 258), and 91% (89%–94%, 125), respectively. Patient age (hazard ratio [HR] for a 10-year increase of 0.92, 95% CI 0.71–1.19; p = 0.5), presence of a macrocystic tumor (HR 0.59, 95% CI 0.14–2.46; p = 0.5), and treated tumor volume (HR for a 1-cm 3 increase of 1.02, 95% CI 0.88–1.18; p = 0.8) were not significantly associated with the risk of salvage. Three distinct post-SRS tumor behavior patterns were observed, with 13% of patients demonstrating tumor pseudoprogression, all but 4 of whom demonstrated pseudoprogression by year 5 post-SRS. CONCLUSIONS SRS demonstrates durable tumor control through 15 years of follow-up in most patients (91%); however, a minority are found to still experience SRS failure even beyond 10 years of surveillance. Although occurring in only a minority of patients, tumor pseudoprogression can be evident out to 5 years or longer post-SRS.

OBJECTIVE Wait-and-scan surveillance is now commonly employed for initial management of small- and medium-sized vestibular schwannomas. Although small differences in tumor size are unlikely to impact outcomes significantly, treatment with either radiosurgery or microsurgery is usually recommended following radiological detection of tumor growth. The objective of the current study was to identify potential inflection points in vestibular schwannoma tumor size, where the risks of treatment with single-fraction stereotactic radiosurgery (SRS) accelerate to inform timing of intervention. METHODS Adult (≥ 18 years old) patients with sporadic vestibular schwannoma who underwent SRS from 2000 through 2022 were included. RESULTS A total of 749 patients with a median age at SRS of 62 years were studied, the majority (n = 566 [76%]) of whom had tumors extending into the cerebellopontine angle (CPA) at SRS. The optimal tumor size cut point to predict SRS failure and need for salvage treatment was 4 mm or more of CPA extension (c-index 0.59, HR 3.60, p = 0.01). The optimal tumor size cut point to predict the outcome of facial nerve paresis was 13 mm or more of CPA extension, resulting in a c-index of 0.63 (HR 2.88, p = 0.01). Among patients with at least 3 months of surveillance before SRS, those with a tumor growth rate ≥ 2.5 mm/year were more likely to undergo salvage treatment than those with a growth rate < 2.5 mm/year, although this difference did not achieve statistical significance (HR 1.82, p = 0.18). CONCLUSIONS The risk of SRS failure requiring salvage treatment and the risk of post-SRS facial nerve paralysis increase at sizes of approximately 4 and 13 mm extension into the CPA, respectively, providing a size threshold anchor to help guide treatment decision-making regarding timing of SRS. Furthermore, rapid tumor growth during the initial wait-and-scan period may be associated with an increased risk of radiosurgical failure, which may influence choice of treatment.

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.