A Modified Technique for Interventional MRI-Guided Deep Brain Stimulation Using the ClearPoint System.

BACKGROUND: Deep brain stimulation (DBS) is increasingly performed using imaging-based techniques, which are rapidly evolving to minimize invasiveness and use limited resources efficiently. OBJECTIVE: To describe a modified surgical technique for interventional MRI-guided stereotactic procedures using ClearPoint. METHODS: A total of 160 consecutive DBS cases for Parkinson disease (48%), essential tremor (44%), dual essential tremor/Parkinson disease (3%), and dystonia (5%) were studied. Technique modifications included (1) preplanning the target/trajectory, (2) adoption of a smaller incision and new stereotactic frame, (3) changing the sequence of surgical steps, aiming to final target PRIOR to drilling, (4) reducing burr hole size, (5) minimizing dural opening, and (6) anchoring leads with a bio cement/plate combination in lieu of commercial devices. Demographic data, radial error, number of passes, and case time were prospectively collected while complications and clinical outcomes were retrospectively assessed. RESULTS: One hundred and forty seven DBS patients had 262 total leads placed. Average radial error was 0.41 mm bilaterally. Seventy nine leads had error <0.2 mm; 6 leads had error >1 mm. Pin-to-stylet insertion time, pin-to-frame removal time, and pin-to-room departure time were 2 hours 1 minute, 2 hours 48 minutes, and 3 hours 16 minutes, respectively, and were significantly shorter than those obtained with the original ClearPoint technique for our first 150 DBS cases ( P < .0001). Complications included infection with hardware removal (2.5%) and superficial hemorrhage without permanent neurological sequelae (1.9%). CONCLUSION: The modified ClearPoint technique maintains accuracy while reducing invasiveness and MRI time. This workflow can be expanded to other applications, including laser interstitial thermal therapy and gene delivery.

George Chance and Frank Holdsworth: Understanding Spinal Instability and the Evolution of Modern Spine Injury Classification Systems.

The concept of spinal cord injury has existed since the earliest human civilizations, with the earliest documented cases dating back to 3000 BC under the Egyptian Empire. Howevr, an understanding of this field developed slowly, with real advancements not emerging until the 20th century. Technological advancements including the dawn of modern warfare producing mass human casualties instigated revolutionary advancement in the field of spine injury and its management. Spine surgeons today encounter "Chance" and "Holdsworth" fractures commonly; however, neurosurgical literature has not explored the history of these physicians and their groundbreaking contributions to the modern understanding of spine injury. A literature search using a historical database, Cochrane, Google Scholar, and PubMed was performed. As needed, hospitals and native universities were contacted to add their original contributions to the literature. George Quentin Chance, a Manchester-based British physician, is well known to many as an eminent radiologist of his time who described the eponymous fracture in 1948. Sir Frank Wild Holdsworth (1904-1969), a renowned British orthopedic surgeon who laid a solid foundation for rehabilitation of spinal injuries under the aegis of the Miners' Welfare Commission, described in detail the management of thoraco-lumbar junctional rotational fracture. The work of these 2 men laid the foundation for today's understanding of spinal instability, which is central to modern spine injury classification and management algorithms. This historical vignette will explore the academic legacies of Sir Frank Wild Holdsworth and George Quentin Chance, and the evolution of spinal instability and spine injury classification systems that ensued from their work.

Focal epilepsy caused by single cerebral cavernous malformation (CCM) is associated with regional and global resting state functional connectivity (FC) disruption.

Epilepsy, including the type with focal onset, is increasingly viewed as a disorder of the brain network. Here we employed the functional connectivity (FC) metrics estimated from the resting state functional MRI (rsfMRI) to investigate the changes of brain network associated with focal epilepsy caused by single cerebral cavernous malformation (CCM). Eight CCM subjects and 21 age and gender matched controls were enrolled in the study. Seven of 8 CCM subjects underwent surgical resection of the CCM and became seizure free and 4 of the surgical subjects underwent a repeat rsfMRI study. We showed that there was both regional and global disruption of the FC values among the CCM subjects including decreased in homotopic FC (HFC) and global FC (GFC) in the regions of interest (ROIs) where the CCMs were located. There was also the disruption of the default mode network (DMN) especially the FC between the middle prefrontal cortex (MPFC) and the right lateral parietal cortex (LPR) among these individuals. We observed the trend of alleviation of these disruptions after the individual has become seizure free from the surgical resection of the CCM. Using a voxel-based approach, we found the disruption of the HFC and GFC in the brain tissue immediately adjacent to the CCM and the severity of the disruption appeared inversely proportional to the distance of the brain tissue to the lesion. Our findings confirm the disruption of normal brain networks from focal epilepsy, a process that may be reversible with successful surgical treatments rendering patients seizure free. Some voxel-based metrics may help identify the epileptogenic zone and guide the surgical resection.

Minimally invasive spine surgery in the pediatric and adolescent population: A case series.

BACKGROUND: There is scant literature evaluating the indications, techniques, and outcomes of minimally invasive spine (MIS) surgery undertaken for pediatric and adolescent spine pathology. Our study attempts to evaluate the safe and effective use of MIS techniques in pediatric and adolescent patients and to appreciate the technical nuances of MIS surgery for this age group. METHODS: Consecutive pediatric and adolescent patients undergoing elective MIS lumbar procedures, from 2008 to 2016, were retrospectively analyzed from the practice of a single fellowship-trained academic spinal neurosurgeon. Information was retrieved regarding procedure and disease pathology. Descriptive data was obtained including age, sex, body mass index (BMI), insurance coverage, smoking status, and co-morbidities. Outcome measures were recorded including intraoperative complications, revision surgery, and return-to-function. RESULTS: Sixteen patients underwent 17 surgeries. The median BMI was 29.2 (range, 20.8-41.5). Age ranged from 12 to 19 years. Nearly 20% of the patients in our series were smokers. Most patients underwent discectomy, with L5-S1 being the most common level. One patient underwent direct pars defect repair and another underwent recurrent discectomy. More than 90% of the patients were complication-free at follow-up period of 6 months. One patient had a recurrent disc herniation and another had a superficial wound infection. Overall, 82.4% patients enjoyed full return to sports such as weight lifting, gymnastics, and contact sports. One patient required pain management to help alleviate ongoing pain. Another patient required a course of outpatient rehabilitation to help with a "foot drop." CONCLUSION: Our series illustrates the effective application of MIS techniques among carefully selected pediatric patients. Emphasis is on using a smaller (16 mm) tubular retractor and causing minimal disruption of paraspinal osseo-tendinous structures. MIS techniques can be successfully applied to the pediatric and adolescent age group.

Seven Intracranial Aneurysms in One Patient: Treatment and Review of Literature.

Before the advent of endovascular coiling, patients with multiple intracranial aneurysms were treated with surgical clipping; however, with the advancements in endovascular technology, intracranial aneurysms can be treated with surgical clipping and/or endovascular coiling. We describe a case of subarachnoid hemorrhage in a patient with 7 intracranial aneurysms. A 45-year-old female developed a sudden headache and left sided hemiparesis. Initial workup showed a subarachnoid hemorrhage in the right Sylvian fissure. Further angiographic workup showed 7 intracranial aneurysms (left and right middle cerebral artery bifurcation, right middle cerebral artery, anterior communicating artery, left posterior communicating artery, right posterior inferior cerebellar artery, and left superior cerebellar artery). The patient underwent two craniotomies for surgical clipping of the anterior circulation aneurysms and endovascular stent-assisted coils for the posterior circulation aneurysms. The need for anti-platelet agents for endovascular treatment of the posterior circulation aneurysms and clinical presentation warranted surgical clipping of the anterior circulation aneurysms prior to endovascular therapy. We describe a case report and decision making for a patient with multiple intracranial aneurysms treated with surgical clipping and endovascular coiling.

Unilateral Acute Closed-Angle Glaucoma After Elective Lumbar Surgery Reveals Multiple Intracranial Aneurysms. A Case Report and Discussion on Workup of Differential Diagnoses.

The purpose of our paper is to present a case of a rare complication of posterior lumbar surgery. Our patient presented for elective lumbar decompression, which was complicated by durotomy. She then developed sudden headache and right eye pain once upright on postoperative day 2. Then on postoperative day 3, she developed a dilated nonreactive pupil with extraocular movements intact. A computed tomography scan of the head was negative for subarachnoid hemorrhage. Magnetic resonance angiography showed a possible right posterior communicating artery aneurysm. She was transferred to a tertiary center with a severe headache and a nonreactive pupil, raising concern for evolving third nerve palsy due to aneurysm. A cerebral angiogram was performed and showed multiple aneurysms. Aneurysm location did not explain the patient's symptoms, and ophthalmology was consulted. Elevated intraocular pressure was noted, and the patient was diagnosed with acute angle-closure glaucoma (AACG). Our patient was medically treated and subsequently underwent laser peripheral iridotomy. She has had improved vision and pupillary function at 1 month follow-up. The diagnosis is complicated by a durotomy, which led to cascade in the differential diagnosis to rule out intracranial pathology. Her age and home medications, which had sympathomimetic effects, placed her at increased risk, but lying prone in the dark under the drapes was likely the lead causative factor. In conclusion, a postoperative posterior spine patient with eye pain and changes in vision and pupils should be evaluated with AACG in mind due to the devastating consequences if left untreated or treatment is delayed.