A bioresorbable peripheral nerve stimulator for electronic pain block.

Local electrical stimulation of peripheral nerves can block the propagation of action potentials, as an attractive alternative to pharmacological agents for the treatment of acute pain. Traditional hardware for such purposes, however, involves interfaces that can damage nerve tissue and, when used for temporary pain relief, that impose costs and risks due to requirements for surgical extraction after a period of need. Here, we introduce a bioresorbable nerve stimulator that enables electrical nerve block and associated pain mitigation without these drawbacks. This platform combines a collection of bioresorbable materials in architectures that support stable blocking with minimal adverse mechanical, electrical, or biochemical effects. Optimized designs ensure that the device disappears harmlessly in the body after a desired period of use. Studies in live animal models illustrate capabilities for complete nerve block and other key features of the technology. In certain clinically relevant scenarios, such approaches may reduce or eliminate the need for use of highly addictive drugs such as opioids.

Decompression of Lumbar Central Spinal Canal Stenosis Following Minimally Invasive Transforaminal Lumbar Interbody Fusion.

STUDY DESIGN: This was a retrospective clinical series. OBJECTIVE: The objective of this study was to evaluate radiologic changes in central spinal canal dimensions following minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) with placement of a static or an expandable interbody device. SUMMARY OF BACKGROUND DATA: MIS-TLIF is used to treat lumbar degenerative diseases and low-grade spondylolisthesis. MIS-TLIF enables direct and indirect decompression of lumbar spinal stenosis, with patients experiencing relief from radiculopathy and neurogenic claudication. However, the effects of MIS-TLIF on the central spinal canal are not well-characterized. MATERIALS AND METHODS: We identified patients who underwent MIS-TLIF for degenerative lumbar spondylolisthesis and concurrent moderate to severe spinal stenosis. We selected patients who had both preoperative and postoperative magnetic resonance imaging (MRI) and upright lateral radiographs of the lumbar spine. Measurements on axial T2-weighted MRI scans include anteroposterior and transverse dimensions of the dural sac and osseous spinal canal. Measurements on radiographs include disk height, neural foraminal height, segmental lordosis, and spondylolisthesis. We made pairwise comparisons between each of the central canal dimensions and lumbar sagittal segmental radiologic outcome measures relative to their corresponding preoperative values. Correlation coefficients were used to quantify the association between changes in lumbar sagittal segmental parameters relative to changes in radiologic outcomes of central canal dimensions. Statistical analysis was performed for "all patients" and further stratified by interbody device subgroups (static and expandable). RESULTS: Fifty-one patients (age 60.4 y, 68.6% female) who underwent MIS-TLIF at 55 levels (65.5% at L4-L5) were included in the analysis. Expandable interbody devices were used in 45/55 (81.8%) levels. Mean duration from surgery to postoperative MRI scan was 16.5 months (SD 11.9). MIS-TLIF was associated with significant improvements in dural sac dimensions (anteroposterior +0.31 cm, transverse +0.38 cm) and osseous spinal canal dimensions (anteroposterior +0.16 cm, transverse +0.32 cm). Sagittal lumbar segmental parameters of disk height (+0.56 cm), neural foraminal height (+0.35 cm), segmental lordosis (+4.26 degrees), and spondylolisthesis (-7.5%) were also improved following MIS-TLIF. We did not find meaningful associations between the changes in central canal dimensions relative to the corresponding changes in any of the sagittal lumbar segmental parameters. Stratified analysis by interbody device type (static and expandable) revealed similar within-group changes as in the overall cohort and minimal between-group differences. CONCLUSIONS: MIS-TLIF is associated with radiologic decompression of neural foraminal and central spinal canal stenosis. The mechanism for neural foraminal and central canal decompression is likely driven by a combination of direct and indirect corrective techniques.

Locoregional Therapy Approaches for Hepatocellular Carcinoma: Recent Advances and Management Strategies.

Hepatocellular carcinoma (HCC) is the most common primary liver malignancy and third leading cause of cancer-related mortality worldwide. While surgical resection and transplantation are the standard first-line treatments for early-stage HCC, most patients do not fulfill criteria for surgery. Fortunately, catheter-directed and percutaneous locoregional approaches have evolved as major treatment modalities for unresectable HCC. Improved outcomes have been achieved with novel techniques which can be employed for diverse applications ranging from curative-intent for small localized tumors, to downstaging or bridging to resection and transplantation for early and intermediate disease, and locoregional control and palliation for advanced disease. This review explores recent advances in liver-directed techniques for HCC including bland transarterial embolization, chemoembolization, radioembolization, and ablative therapies, with a focus on patient selection, procedural technique, periprocedural management, and outcomes.

Spinal dural arteriovenous fistula masquerading as subdural hematoma.

BACKGROUND: This case highlights an angiographically occult spinal dural AVF presenting with a spinal subdural hematoma. While rare, it is important that clinicians be aware of this potential etiology of subdural hematomas before evacuation. CASE DESCRIPTION: A 79-year-old female presented with acute lumbar pain, paraparesis, and a T10 sensory level loss. The MRI showed lower cord displacement due to curvilinear/triangular enhancement along the right side of the canal at the T12-L1 level. The lumbar MRA, craniospinal CTA, and multivessel spinal angiogram were unremarkable. A decompressive exploratory laminectomy revealed a subdural hematoma that contained blood products of different ages, and a large arterialized vein exiting near the right L1 nerve root sheath. The fistula was coagulated and sectioned. Postoperatively, the patient regained normal function. CONCLUSION: Symptomatic subdural thoracolumbar hemorrhages from SDAVF are very rare. Here, we report a patient with an acute paraparesis and T10 sensory level attributed to an SDAVF and subdural hematoma. Despite negative diagnostic studies, even including spinal angiography, the patient underwent surgical intervention and successful occlusion of the SDAVF.

Validation of the Disabilities of the Arm, Shoulder, and Hand in Patients Undergoing Cervical Spine Surgery.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To evaluate the performance and convergent validity of the disabilities of the arm, shoulder, and hand (DASH) in comparison with the visual analog scale (VAS) for pain, and neck disability index (NDI) in patients undergoing cervical spine surgery. SUMMARY OF BACKGROUND DATA: Neck-specific disability scales do not adequately assess concurrent upper extremity involvement in patients with cervical spine disorders. The DASH is a patient-reported outcomes (PRO) instrument designed to measure functional disability due to upper extremity conditions but has additionally been shown to perform well in patients with neck disorders. METHODS: We identified patients who underwent cervical spine surgery at our institution between 2013 and 2016. We collected demographic information, clinical characteristics, and PRO measures-DASH, VAS, NDI-preoperatively, as well as early and late postoperatively. We calculated descriptive statistics and changes from baseline in PROs. Correlation coefficients were used to quantify the association between PRO measures. The analysis was stratified by radiculopathy and myelopathy diagnoses. RESULTS: A total of 1046 patients (52.8% male) with PROs data at baseline were included in the analysis. The mean age at surgery ±â€ŠSD was 57.2 ±â€Š11.3 years, and postoperative follow-up duration 12.7 ±â€Š10.7 months. The most common surgical procedure was anterior cervical discectomy and fusion (71.1%). Patients experienced clinically meaningful postoperative improvements in all PRO measures. The DASH showed moderate positive correlations with VAS preoperatively (Spearman rho = 0.43), as well as early (rho = 0.48) and late postoperatively (rho = 0.60). DASH and NDI scores were strongly positively correlated across operative states (Preoperative rho = 0.74, Early Postoperative rho = 0.78, Late Postoperative rho = 0.82). Stratified analysis by preoperative diagnosis showed similar within-groups trends and pairwise correlations. However, radiculopathy patients experienced larger magnitude early and late change scores. CONCLUSION: The DASH is a valid and responsive PRO measure to evaluate disabling upper extremity involvement in patients undergoing cervical spine surgery. LEVEL OF EVIDENCE: 3.

T-Configuration Horizontal Low-Profile Visualized Intraluminal Support (LVIS Jr) Device-Assisted Coiling for Treatment of Basilar Tip Aneurysms: A Technical Note.

BACKGROUND: Provided certain anatomic considerations, stent-assisted coiling of basilar apex aneurysms can be performed using a single stent placed in a horizontal T-configuration across the aneurysm neck prior to coil deployment, although this has predominantly been described using older-generation stents. The development of the Low-profile Visualized Intraluminal Support (LVIS Jr) device has provided greater versatility than previous stents, including use in smaller vessels, the ability to be resheathed, and improved flow diversion properties. METHODS: To our knowledge, we report the first use of the LVIS Jr device in a horizontal T-configuration across the aneurysm neck prior to coil deployment in 2 patients for the treatment of basilar apex aneurysms. This technique requires robust posterior communicating artery aneurysms and a second site of vascular access. RESULTS: Both patients demonstrated good outcomes following the procedure with no adverse sequelae. One patient required retreatment for recurrence after 1 year and was able to undergo further coiling without difficulty. CONCLUSIONS: Use of the LVIS Jr device allows greater versatility in horizontal T-configuration stent-assisted coil embolization, when compared with other available intracranial stents. This provides another tool to treat basilar apex aneurysms with improved coil occlusion and a theoretically decreased risk of thromboembolic events.

Bilateral Recurrent Dysplastic Cerebellar Gangliocytoma (Lhermitte-Duclos Disease) in Cowden Syndrome: A Case Report and Literature Review.

BACKGROUND: Dysplastic gangliocytoma (Lhermitte-Duclos disease [LDD]) typically presents as a PTEN (phosphatase and tensin homolog)-positive, insidious unilateral mass of the cerebellar cortex. Patients can present with symptoms of increased intracranial pressure. Magnetic resonance imaging (MRI) will reveal a characteristic laminar/tigroid appearance. Surgical management has been superior to conservative measures for symptomatic lesions. The outcomes for bilateral craniotomy have not yet been described. CASE DESCRIPTION: A 50-year-old patient with Cowden syndrome had initially presented with vertigo and imbalance. T2-weighted MRI showed a striated pattern of hypointensity and hyperintensity in bilateral cerebellar hemispheres consistent with Lhermitte-Duclos disease. He underwent right posterior fossa craniotomy with near total surgical resection and achieved symptom resolution. However, 3 years later, asymptomatic recurrence of the right-sided LDD and progression of left-sided LDD were noted. These were managed with a 1-year course of temozolomide. Both lesions remained stable until 4 years after completion of temozolomide. MRI demonstrated progression in the left hemisphere requiring a second surgical resection. PTEN analysis of the resected lesion was negative for mutation. CONCLUSIONS: To the best of our knowledge, the present case is the first reported case of bilateral cerebellar hemisphere LDD ultimately managed by temporally dissociated bilateral surgical resections. Our patient was unique in that he had undergone surgery for resection of LDD, followed by a second surgery for contralateral progression 8 years later. The therapeutic options to prevent recurrence are limited, although temozolomide did seem to impede progression. Symptomatic patients will typically benefit most from surgical intervention. Given the strong association between adult LDD and Cowden syndrome, maintaining close follow-up care and possible surveillance imaging will be essential.