Case report: isolated trochlear nerve palsy associated with posterior cerebral artery aneurysm.

We describe a case of isolated trochlear nerve palsy caused by an unruptured posterior cerebral artery (PCA) aneurysm in an 82-year-old male who consulted an ophthalmologist after developing diplopia. Magnetic resonance angiography showed a left PCA aneurysm in the ambient cistern, and T2WI showed an aneurysm compressing the left trochlear nerve to the cerebellar tentorium. Digital subtraction angiography revealed that the lesion was located between the left P2a segment. We attributed this isolated trochlear palsy to left PCA unruptured aneurysm pressure. Thus, we performed stent-assisted coil embolization. The aneurysm was obliterated, and trochlear nerve palsy improved completely.

Optimal surgical indications of endoscopic surgery for traumatic acute subdural hematoma in elderly patients based on a single-institution experience.

Recently, treatment of acute subdural hematoma (ASDH) by minimally invasive surgery with endoscopy has been successfully demonstrated. However, few case series are available on this procedure for ASDH, and the surgical indication has not been established. We retrospectively analyzed the data of patients (n = 26) aged 65 years or older who underwent endoscopic surgery (ES) for ASDH at our institution between January 2011 and March 2019. We then evaluated the surgical outcomes and procedure-related complications in patients who underwent ES. The mean hematoma reduction rate was over 90%. Percentage of favorable outcomes at discharge was 69.2% in ES-treated patients. The presence of a skull fracture, subarachnoid hemorrhage, midline shift/subdural hematoma thickness ratio > 1.0, and early surgery were associated with postoperative IPHs in patients who underwent ES or conventional surgery for ASDH. The present study revealed that ES for elderly patients with ASDH is likely to be an efficient and safe procedure when patients are selected appropriately. However, ES is not recommended in patients with significant IPHs on initial CT scan. Additionally, ES should be carefully considered in cases with the factors, where IPHs may progress following surgery.

[Surgical Technique of Ventral Intermediate Thalamic Deep Brain Stimulation].

Deep brain stimulation(DBS)of ventral intermediate(Vim)thalamic nucleus is an established procedure for tremor disorders, however, there are technical variations among specialists. The most common indications of Vim DBS are essential tremor(ET)and tremor dominant Parkinson's disease(PD), and less commonly other tremor disorders including Holmes tremor are treated with the same procedure. The variations of the surgical technique exist in the preoperative imagings and planning of the DBS electrode trajectory. In this review, we explain about the basic concept of Vim DBS and our surgical method.

The Comparison of Clinical Findings and Treatment Between Unilateral and Bilateral Vertebral Artery Dissection.

BACKGROUND: There are limited clinical studies of bilateral vertebral artery dissection (VAD). OBJECTIVE: To compare the characteristics, imaging findings, and treatments between patients with bilateral and unilateral VAD. METHODS: Between February 2007 and May 2017, 31 (mean age: 53.0 years; 23 men, 8 women) out of 171 VAD patients were hospitalized because of bilateral VAD. Onset type, dissection site, dominant side of the VA, imaging features, treatments, and outcomes were investigated based on medical records. The dominant side of the VA was determined by basi-parallel anatomical scanning. RESULTS: Twenty (64.5%) of 31 patients exhibited bilateral VAD on both sides of V4. The dominant side of the VA was right in 16 patients and left in 15 patients. The pearl and string sign (an angiographical finding with both dilatation and stenosis) was frequently observed on the dominant VAD side, while a tapered occlusion and string sign were most common on the nondominant side. For clinical subtype of VAD, 6 (19.4%) patients had subarachnoid hemorrhage, 10 (32.3%) ischemic stroke, 3 (9.7%) infarction plus subarachnoid hemorrhage, and 12 (38.7%) only headache. The frequency of infarction was increased in bilateral VAD compared with unilateral (P < .05). Surgical intervention was performed in 3 cases, while 14 patients received endovascular intervention. CONCLUSIONS: Infarction occurred frequently in bilateral VAD patients, and 17 patients required an intervention (mainly endovascular) for VA. The treatment strategy varied depending on the clinical subtype, imaging findings of VAD, and morphology of the dominant VAD side.

[Microneurosurgical Treatment for Refractory Entrapment Neuropathy of Suprascapular Nerve:A Case Report].

Suprascapular nerve entrapment is rarely treated by neurosurgeons in Japan. However, it is often observed in post-stroke patients and in cases of accessory nerve injury as a complication of posterior fossa craniotomy. We report a case of suprascapular nerve entrapment due to superior transverse scapular ligament, which was successfully diagnosed and surgically treated. The patient was a 66-year-old female who used be a janitor. She complained of dysesthesia around the shoulder. The diagnosis was made based on the characteristic neurological findings including pain around the scapula, supraspinatus muscle weakness, and favorable but temporary response to suprascapular nerve block. After undergoing conservative management for one and a half year, she decided to undergo the nerve decompression surgery. The surgical treatment was performed under microscope with neuromonitoring. Following surgery, the painful area was dramatically reduced. We believe that suprascapular nerve disorders can be treated with careful neurological evaluation by neurosurgeons.

[Cervical Myelopathy Caused by Chronic and Intermittent Cord Compression by Tumors upon Neck Rotation:A Case Report].

A 35-year-old man with neurofibromatosis type I presented with right arm weakness and gait disturbance that had developed gradually. MR imaging revealed bilateral intra-and extradural tumors at the C1-2 level. Although the adjacent spinal cord was narrowed, there was no evident contact between the tumors and the spinal cord. Computed tomography myelography revealed that the tumors compressed the cord only during neck rotation. The tumors were resected to make an abundant subdural space around the affected cord. The patient's neurological symptoms improved postoperatively. Because contact between the masses and spinal cord only occurred upon neck rotation, we believe it is important to consider the possibility of intermittent compression, termed dynamic rotational canal stenosis, in patients with masses at the C1-2 level, even when such masses are not seen to be in contact with the cervical cord on routine radiological examination.

Potential of Hybrid Assistive Limb Treatment for Ataxic Gait Due to Cerebellar Disorders Including Hemorrhage, Infarction, and Tumor.

Cerebellar hemorrhage (CH) is a severe life-threatening disorder, and surgical treatment is often required in an emergency situation. Even in cases in which the surgical procedure is successful, functional recovery is likely to be delayed because of cerebellar symptoms such as ataxia and gait disturbance. Here, we briefly review the efficacy of hybrid assistive limb (HAL) treatment in neurosurgical practice and propose a new comprehensive treatment strategy for CH to facilitate early neurological recovery. We have experienced cases of ataxic gait due to various etiologies, treated with rehabilitation using the HAL, and our data showed that HAL treatment potentially improves ataxic gait and balance problems. HAL treatment seems to be an effective and promising treatment modality for selected cases. Future studies should evaluate gait appearance and balance, in addition to walking speed, to assess improvement in cerebellar symptoms.

Cerebral and spinal cavernomas associated with Klippel-Trenaunay syndrome: case report and literature review.

Klippel-Trenaunay-Weber syndrome (KTWS) involves a triad of conditions, including cutaneous hemangiomas, venous varicosities, and osseous and soft-tissue hypertrophy of the affected limb. We describe a rare case of multiple cavernomas in the central nervous system in a patient with KTWS. A-64-year-old man with KTWS and a previous brain hemorrhage presented with sudden onset of gait and vesicorectal disturbance. The magnetic resonance imaging scan showed a cavernoma associated with hemorrhage in his lumbosacral spinal cord. Moreover, numerous cavernomas were identified in his brain. He was treated conservatively with no adverse events. Gait disturbance improved, but vesicorectal disturbance did not improve.

Contralateral Cerebral Hypometabolism After Cerebellar Stroke: A Functional Near-Infrared Spectroscopy Study.

INTRODUCTION: We report the changes in cortical activity evaluated using functional near-infrared spectroscopy (fNIRS) in 2 cases with cerebellar stroke. METHODS: Using an fNIRS imaging system, changes in the oxygenated hemoglobin concentration (ΔOxy-Hb) from baseline were estimated. Design and verbal fluency tasks were conducted for evaluation of visuospatial and language functions, respectively. RESULTS: The contralateral prefrontal area showed limited activation compared with the ipsilateral one in the case with either cerebellar stroke. CONCLUSIONS: A negative impact of cerebellar stroke on the multimodal association of cortex, regardless of the type of stroke (infarct or hemorrhage).

Tailor-made rehabilitation approach using multiple types of hybrid assistive limb robots for acute stroke patients: A pilot study.

This article investigated the feasibility of a tailor-made neurorehabilitation approach using multiple types of hybrid assistive limb (HAL) robots for acute stroke patients. We investigated the clinical outcomes of patients who underwent rehabilitation using the HAL robots. The Brunnstrom stage, Barthel index (BI), and functional independence measure (FIM) were evaluated at baseline and when patients were transferred to a rehabilitation facility. Scores were compared between the multiple-robot rehabilitation and single-robot rehabilitation groups. Nine hemiplegic acute stroke patients (five men and four women; mean age 59.4 ± 12.5 years; four hemorrhagic stroke and five ischemic stroke) underwent rehabilitation using multiple types of HAL robots for 19.4 ± 12.5 days, and 14 patients (six men and eight women; mean age 63.2 ± 13.9 years; nine hemorrhagic stroke and five ischemic stroke) underwent rehabilitation using a single type of HAL robot for 14.9 ± 8.9 days. The multiple-robot rehabilitation group showed significantly better outcomes in the Brunnstrom stage of the upper extremity, BI, and FIM scores. To the best of the authors' knowledge, this is the first pilot study demonstrating the feasibility of rehabilitation using multiple exoskeleton robots. The tailor-made rehabilitation approach may be useful for the treatment of acute stroke.

Smile without euphoria induced by deep brain stimulation: a case report.

Poststroke central pain (PSCP) can be a debilitating medication-refractory disorder. We report a single case where right unilateral ventral capsule/ventral striatum (VC/VS) deep brain stimulation was used to treat PSCP and inadvertently induced a smile without euphoria. The patient was a 69 year-old woman who had a stroke with resultant dysesthesia and allodynia in her left hemibody and also a painful left hemibody dystonia. In her case, VC/VS stimulation induced a smile phenomenon, but without a euphoric sensation. This phenomenon was different from the typical smile responses we have observed in obsessive-compulsive disorder cases. This difference was considered to be possibly attributable to impairment in the emotional smile pathway.

The Rad4(TopBP1) ATR-activation domain functions in G1/S phase in a chromatin-dependent manner.

DNA damage checkpoint activation can be subdivided in two steps: initial activation and signal amplification. The events distinguishing these two phases and their genetic determinants remain obscure. TopBP1, a mediator protein containing multiple BRCT domains, binds to and activates the ATR/ATRIP complex through its ATR-Activation Domain (AAD). We show that Schizosaccharomyces pombe Rad4(TopBP1) AAD-defective strains are DNA damage sensitive during G1/S-phase, but not during G2. Using lacO-LacI tethering, we developed a DNA damage-independent assay for checkpoint activation that is Rad4(TopBP1) AAD-dependent. In this assay, checkpoint activation requires histone H2A phosphorylation, the interaction between TopBP1 and the 9-1-1 complex, and is mediated by the phospho-binding activity of Crb2(53BP1). Consistent with a model where Rad4(TopBP1) AAD-dependent checkpoint activation is ssDNA/RPA-independent and functions to amplify otherwise weak checkpoint signals, we demonstrate that the Rad4(TopBP1) AAD is important for Chk1 phosphorylation when resection is limited in G2 by ablation of the resecting nuclease, Exo1. We also show that the Rad4(TopBP1) AAD acts additively with a Rad9 AAD in G1/S phase but not G2. We propose that AAD-dependent Rad3(ATR) checkpoint amplification is particularly important when DNA resection is limiting. In S. pombe, this manifests in G1/S phase and relies on protein-chromatin interactions.

Swallowing outcomes following unilateral STN vs. GPi surgery: a retrospective analysis.

The adverse effects of deep brain stimulation (DBS) surgery on swallowing could potentially exacerbate the natural deterioration of airway protection associated with Parkinson's disease (PD) degeneration and increase the incidence of aspiration pneumonia and associated death. There are no studies that compare swallowing outcomes associated with subthalamic nucleus (STN) versus globus pallidus interna (GPi) DBS surgery; therefore, we completed a retrospective study comparing swallowing outcomes in a cohort of patients with PD who underwent unilateral DBS surgery in either the STN or GPi. A chart review was completed to identify all patients with a diagnosis of PD who received videofluoroscopic swallowing evaluations before DBS and after unilateral DBS in the STN or GPi. The retrospective search yielded 33 patients (STN = 14, GPi = 19) with idiopathic PD who met the inclusion criteria. Mean penetration-aspiration (PA) scores did not change significantly for participants who underwent GPi surgery (z = -.181, p = .857), but mean PA scores significantly worsened for participants who underwent STN DBS (z = -2.682, p = .007). There was a significant improvement in Unified PD Rating Scale (UPDRS) scores off medication before surgery, to off medication and on stimulation after surgery for both groups (F = 23.667, p < .001). Despite the limitations of a retrospective analysis, this preliminary study suggests that unilateral STN DBS may have an adverse effect on swallowing function, while unilateral GPi DBS does not appear to have a similar deleterious effect. This study and other future studies should help to elucidate the mechanisms underpinning the effects of DBS on swallowing function.

Surgical neuroanatomy and programming in deep brain stimulation for obsessive compulsive disorder.

OBJECTIVES: Deep brain stimulation (DBS) has been established as a safe, effective therapy for movement disorders (Parkinson's disease, essential tremor, etc.), and its application is expanding to the treatment of other intractable neuropsychiatric disorders including depression and obsessive-compulsive disorder (OCD). Several published studies have supported the efficacy of DBS for severely debilitating OCD. However, questions remain regarding the optimal anatomic target and the lack of a bedside programming paradigm for OCD DBS. Management of OCD DBS can be highly variable and is typically guided by each center's individual expertise. In this paper, we review the various approaches to targeting and programming for OCD DBS. We also review the clinical experience for each proposed target and discuss the relevant neuroanatomy. MATERIALS AND METHODS: A PubMed review was performed searching for literature on OCD DBS and included all articles published before March 2012. We included all available studies with a clear description of the anatomic targets, programming details, and the outcomes. RESULTS: Six different DBS approaches were identified. High-frequency stimulation with high voltage was applied in most cases, and predictive factors for favorable outcomes were discussed in the literature. CONCLUSION: DBS remains an experimental treatment for medication refractory OCD. Target selection and programming paradigms are not yet standardized, though an improved understanding of the relationship between the DBS lead and the surrounding neuroanatomic structures will aid in the selection of targets and the approach to programming. We propose to form a registry to track OCD DBS cases for future clinical study design.

Microlesion Effect Induced by Electrode Implantation in the Posteroventral Globus Pallidus Interna for Severe Dystonic Tics.

Background: Tourette syndrome (TS) is a neurologic condition characterized by motor and phonic tics. Dystonic tics, including blepharospasm, are considered atypical or unusual in severe TS. Case Report: We report a severe case of TS with facial dystonic tics resembling blepharospasm in which the microlesion effect and a sustained therapeutic effect was observed with bilateral globus pallidus interna (GPi) deep brain stimulation (DBS). Discussion: Bilateral GPi DBS can be beneficial for blepharospasm-like tics and severe symptoms of TS. The improvements seen can be explained by the microlesion effect induced by DBS lead placement in the GPi.

Asymptomatic cable twisting in a patient with impending Twiddler syndrome detected during deep brain stimulation surgery for Parkinson's disease: A case report.

Background: Deep brain stimulation (DBS) has consistently demonstrated high efficacy and safety in patients with Parkinson's disease. Twiddler's syndrome is a rare occurrence of hardware failure in patients undergoing neuromodulation. We report here a case of subclinical cable twisting jeopardizing Twiddler's syndrome in a patient with Parkinson's disease who underwent DBS surgery targeting the globus pallidus internus (GPI). Case Description: A 70-year-old woman with a 7-year history of Parkinson's disease refractory to medication was referred to our department for treatment of involuntary movements of the left hand and leg. She underwent right GPI DBS implantation. Left GPI DBS implantation was subsequently planned to manage resting tremors that developed in the right leg after the first surgery at around one year after the first surgery. During a routine check-up before the second surgery, we incidentally detected Twiddler's syndrome. The patient showed no neurological deficits in the left extremities, the same as before right GPI DBS. We performed left GPI DBS concomitantly with the revision of the implantable pulse generator and extension wire. Conclusion: Twiddler's syndrome is a rare complication of DBS. Subclinical risk of cable twisting jeopardizing Twiddler's syndrome is rarely detected without clinical indications of hardware failure. Neurosurgeons should be cognizant of and regularly monitor the implanted device in case serious complications occur.

Surgical Concepts and Long-term Outcomes of Thalamic Deep Brain Stimulation in Patients with Severe Tourette Syndrome: A Single-center Experience.

Tourette syndrome (TS) is a developmental neuropsychiatric disorder that is characterized by tic movements. Deep brain stimulation (DBS) may be a treatment option for severe cases refractory to medical and behavioral therapies. In this study, we reviewed the surgical techniques used for DBS in patients with severe TS and its clinical outcomes and sought to determine the optimal surgical procedure and current issues based on our experience and the literature. A total of 14 patients, consisting of 13 men and 1 woman, who underwent centromedian thalamic DBS and were followed up for a mean duration of 2.3 ± 1.0 years, participated in this study. The mean Yale Global Tic Severity Scale severity score significantly improved from 41.4 ± 7.0 at baseline to 19.8 ± 11.4 at 6 months (P = 0.01) and 12.7 ± 6.2 at the last follow-up (P < 0.01). Moreover, the mean Yale Global Tic Severity Scale impairment score significantly improved from 47.1 ± 4.7 at baseline to 23.1 ± 11.1 at 6 months (P < 0.01) and 7.6 ± 2.9 at the last follow-up (P < 0.01). However, there were problems with continuous postoperative monitoring (three cases were lost to follow-up) and surgery-related adverse events, including one case each of lead misplacement and a delayed intracerebral hemorrhage due to severe self-injurious tics. This study aimed to highlight not only the clinical efficacy of DBS for TS but also its challenges. Clinicians should understand the three-dimensional brain anatomy so that they can perform precise surgical procedures, avoid adverse events, and achieve favorable outcomes of DBS for TS.

Proceedings of the 11th Annual Deep Brain Stimulation Think Tank: pushing the forefront of neuromodulation with functional network mapping, biomarkers for adaptive DBS, bioethical dilemmas, AI-guided neuromodulation, and translational advancements.

The Deep Brain Stimulation (DBS) Think Tank XI was held on August 9-11, 2023 in Gainesville, Florida with the theme of "Pushing the Forefront of Neuromodulation". The keynote speaker was Dr. Nico Dosenbach from Washington University in St. Louis, Missouri. He presented his research recently published in Nature inn a collaboration with Dr. Evan Gordon to identify and characterize the somato-cognitive action network (SCAN), which has redefined the motor homunculus and has led to new hypotheses about the integrative networks underpinning therapeutic DBS. The DBS Think Tank was founded in 2012 and provides an open platform where clinicians, engineers, and researchers (from industry and academia) can freely discuss current and emerging DBS technologies, as well as logistical and ethical issues facing the field. The group estimated that globally more than 263,000 DBS devices have been implanted for neurological and neuropsychiatric disorders. This year's meeting was focused on advances in the following areas: cutting-edge translational neuromodulation, cutting-edge physiology, advances in neuromodulation from Europe and Asia, neuroethical dilemmas, artificial intelligence and computational modeling, time scales in DBS for mood disorders, and advances in future neuromodulation devices.

Cerebral venous infarction: a potentially avoidable complication of deep brain stimulation surgery.

OBJECT: Despite numerous reports on the morbidity and mortality of deep brain stimulation (DBS), cerebral venous infarction has rarely been reported. We present four cases of venous infarct secondary to DBS surgery. METHODS: The diagnosis of venous infarction was based on 1) delayed onset of new neurologic deficits on postoperative day 1 or 2; 2) significant edema surrounding the superficial aspect of the implanted lead, with or without subcortical hemorrhage on CT scan. RESULTS: Four cases (0.8% per lead, 1.3% per patient) of symptomatic cerebral venous infarction were identified out of 500 DBS lead implantation procedures between July 2002 and August 2009. All four patients had Parkinson's disease. Their DBS leads were implanted in the subthalamic nucleus (n = 2), and the globus pallidus internus (n = 2). Retrospective review of the targeting confirmed that the planned trajectory passed within 3 mm of a cortical vein in two cases for which contrast-enhanced preoperative magnetic resonance (MR) imaging was available. In the other two cases, contrasted targeting images were not obtained preoperatively. CONCLUSION: Cerebral venous infarction is a potentially avoidable, but serious complication. To minimize its incidence, we propose the use of high-resolution, contrast-enhanced, T1-weighted MR images to delineate cerebral venous anatomy, along with careful stereotactic planning of the lead trajectory to avoid injury to venous structures.

Fatal hemorrhage from AVM after DBS surgery: case report.

OBJECTIVES: Intracranial hemorrhage is a crucial complication of deep brain stimulation (DBS) surgery. The bleeding caused by mechanical tissue injury due to microelectrode and/or DBS electrode lead insertion has been well studied. However, hemorrhage caused by a congenital underlying disease such as vascular malformation has not been examined carefully. MATERIALS AND METHODS: We encountered a case of intracerebral hemorrhage from arteriovenous malformation (AVM) after DBS surgery. Preoperative magnetic resonance (MR) imaging did not show any abnormality in the patient. Computed tomography (CT) images taken immediately after the surgery did not show any intracranial hematoma and other abnormal findings. However, the patient did not recover from the general anesthesia, and hemorrhage in the left occipital lobe was detected by CT performed a day after the surgery. The location of the hematoma was markedly distant from the trajectory of DBS leads. Evacuation of the hematoma under general anesthesia was immediately performed. RESULTS: As an intraoperative finding, we noted the presence of abnormal vessels inside the hematoma in the occipital lobe. Tissue specimens including the abnormal vessels were obtained for histopathological analysis, results of which led to the diagnosis was AVM. CONCLUSION: Despite its low incidence, we would like to advise that such a type of hemorrhage could occur and measures should be taken to prevent its occurrence as much as possible. Preoperative detection of abnormal vessels by MR angiography and/or CT angiography might be helpful. Moreover, paying close attention to the possible leakage of cerebrospinal fluid during surgery might be important.