Neurosurgical focus最新文献

Objective: MR-guided focused ultrasound (MRgFUS) is an evolving technology with numerous present and potential applications in pediatric neurosurgery. The aim of this study was to describe the use of MRgFUS, technical challenges, complications, and lessons learned at a single children's hospital.

Methods: A retrospective analysis was performed of a prospectively collected database of all pediatric patients undergoing investigational use of MRgFUS for treatment of various neurosurgical pathologies at Children's National Hospital. Treatment details, clinical workflow, and standard operating procedures are described. Patient demographics, procedure duration, and complications were obtained through a chart review of anesthesia and operative reports.

Results: In total, 45 MRgFUS procedures were performed on 14 patients for treatment of diffuse intrinsic pontine glioma (n = 12), low-grade glioma (n = 1), or secondary dystonia (n = 1) between January 2022 and April 2024. The mean age at treatment was 9 (range 5-22) years, and 64% of the patients were male. With increased experience, the total anesthesia time, sonication time, and change in core body temperature during treatment all significantly decreased. Complications affected 4.4% of patients, including 1 case of scalp edema and 1 patient with a postprocedure epidural hematoma. Device malfunction requiring abortion of the procedure occurred in 1 case (2.2%). Technical challenges related to transducer malfunction and sonication errors occurred in 6.7% and 11.1% of cases, respectively, all overcome by subsequent user modifications.

Conclusions: The authors describe the largest series on MRgFUS technical aspects in pediatric neurosurgery at a single institution, comprising 45 total treatments. This study emphasizes potential technical challenges and provides valuable insights into the nuances of its application in pediatric patients.

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.

Objective: Advancements in MRI-guided focused ultrasound (MRgFUS) technology have led to the successful treatment of select movement disorders. Based on the comparative success between ablation and deep brain stimulation, interest arises in focused ultrasound (FUS) as a promising treatment modality for psychiatric illnesses. In this systematic review, the authors examined current applications of FUS for psychiatric conditions and explored its potential opportunities and challenges.

Methods: The authors performed a comprehensive review using the PRISMA guidelines of studies investigating psychiatric applications for FUS. Articles indexed on PubMed between 2014 to 2024 were included. The authors synthesized the psychiatric conditions treated, neural targets, outcomes, study design, and sonication parameters, and they reviewed important considerations for the treatment of psychiatric disorders with FUS. They also discussed active clinical trials in this research domain.

Results: Of 250 articles, 10 met the inclusion criteria. Eight articles investigated the clinical, safety, and imaging correlates of MRgFUS in obsessive-compulsive disorder (OCD), whereas 3 examined treatment-resistant depression. Bilateral anterior capsulotomy resulted in a full responder rate of 67% (≥ 35% reduction in the Yale-Brown Obsessive-Compulsive Scale score) and 33% (≥ 50% reduction in the score on the Hamilton Rating Scale for Depression) in OCD and treatment-resistant depression, respectively. Sonications ranged from 8 to 36 with targeted lesional temperatures of 51°C-56°C. Lesions in the anterodorsal aspect of the anterior limb of the internal capsule (ALIC) and increased functional connectivity to the left dorsolateral prefrontal cortex and dorsal anterior cingulate cortex significantly predicted reduction in symptoms among patients with OCD, with decreases in beta-band activity in the frontocentral and temporal regions associated with reductions in depression and anxiety. Treatment of the nucleus accumbens with low-intensity FUS (LIFU) in patients with opioid-use disorders resulted in significant reductions in cue-reactive cravings, lasting up to 90 days. No serious adverse events were reported, including cognitive decline. Side effects were generally mild and transient, consisting of headaches, pin-site swelling, and nausea. Fourteen active clinical trials were identified, primarily targeting depression with LIFU.

Conclusions: Currently, FUS for psychiatric conditions is centered on OCD, with early pilot studies demonstrating promising safety and efficacy. Further research expanding on defining optimal patient selection, study design, intensity, and sonication parameters is warranted, particularly as FUS expands to other psychiatric illnesses and incorporates LIFU paradigms. Ethical considerations such as patient consent and equitable access also remain paramount.

Objective: MR-guided focused ultrasound (MRgFUS) thalamotomy is an incisionless neurosurgical treatment for patients with medically refractory essential tremor and tremor-dominant Parkinson's disease. A low skull density ratio (SDR) < 0.40 is a known risk factor for treatment failure. The aim of this study was to identify useful sonication strategies for patients with a low SDR < 0.40 by modifying the standard sonication protocol using maximum high-energy sonication while minimizing the number of sonications.

Methods: The authors retrospectively analyzed the effects of modified MRgFUS sonication on low-SDR tremor patients. All patients underwent head CT scans to calculate their SDR. The SDR threshold for MRgFUS thalamotomy was 0.35. The patients in the early series underwent the standard sonication protocol targeting the ventral intermediate nucleus contralateral to the treated hand side. The patients with a low SDR < 0.40 in the late series underwent a modified sonication protocol, in which the number of alignment sonications was minimized and high-energy treatment sonication (> 36,000 J) was used. The authors evaluated the lesion volume the following day and tremor improvement and adverse events 3 and 12 months after the procedure. The sonication patterns between low-SDR patients treated using different sonication protocols were examined using Fisher's exact test. ANOVA was used to examine the lesion volume and tremor improvement in high- and low-SDR patients treated using different sonication protocols.

Results: Among 41 patients with an SDR < 0.40, 14 underwent standard sonication and 27 underwent modified sonication. Fewer alignment sonications and high-energy treatment sonications were used in the modified sonication group compared with the standard group (p < 0.001). The duration of modified sonication was significantly shorter than that of standard sonication (p < 0.001). The lesion volume and tremor improvement significantly differed among the high- and low-SDR groups with different sonication protocols (p < 0.001). Low-SDR patients treated using modified sonication protocols had comparable lesion volume and tremor improvement to the high-SDR group. The modified sonication protocol did not significantly increase adverse intraprocedural and postprocedural events.

Conclusions: Minimizing alignment sonications and applying high-energy sonication in early treatment help to create an optimal lesion volume and control tremor in low-SDR patients.

Objective: Chronic low-back pain (LBP) is a leading cause of disability worldwide, and traditional pharmacotherapy fails to provide relief for many individuals with this condition. An estimated 15% of chronic LBP cases can be attributed to the facet joint. High-intensity focused ultrasound (HIFU) is a recent technology that enables noninvasive thermal ablation of tissue and has shown efficacy in treating tumors, neuropathic pain, and painful bone metastases. In this systematic review, the authors summarize the literature on lumbar facet joint-mediated pain treated with HIFU and report the effectiveness of HIFU on pain outcomes.

Methods: All full-text English-language articles describing the use of focused ultrasound for facet joint pain were screened using the PubMed/MEDLINE, Embase, Cochrane Library, Scopus, and Web of Science databases. Clinical studies were assessed for bias using the methodological index for nonrandomized studies.

Results: Eleven studies (6 preclinical and 5 clinical) reporting on 50 patients were included. Eight of these studies (73%) used MR-guided focused ultrasound ablation and 3 used fluoroscopy. The medial branch nerve and posterior facet joint capsule were the most common targets for focused ablation. Although the energy used ranged from 300 to 2000 J, clinical studies predominantly operated in the range of 1000 to 1500 J. Pain reduction was seen in all clinical studies, with multiple-point reductions from average baseline pain scores in 6-12 months. No study reported any adverse events or complications.

Conclusions: HIFU can be effective in treating chronic low-back pain arising from the facet joint. Further clinical studies should explore the long-term effects of HIFU and monitor changes in pain reduction over time.