Minimum and early high-energy sonication protocol of MR-guided focused ultrasound thalamotomy for low-skull density ratio patients with essential tremor and Parkinson's disease.

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.

Intramedullary feeder aneurysm of a cervical epidural arteriovenous fistula causing myelopathy: a case report and literature review.

While a craniocervical junction (CCJ) epidural arteriovenous fistula (EDAVF) may present with hemorrhagic myelopathy from an associated feeder aneurysm on rare occasions, non-hemorrhagic myelopathy from such an aneurysm remains unreported. A woman in her late sixties presented with cervical myelopathy due to a non-hemorrhagic intramedullary aneurysm associated with CCJ-EDAVF. The intramedullary aneurysm originated from the spinal pial artery supplied by the anterior spinal artery. Direct surgical fistula coagulation and feeder obliteration resulted in the disappearance of the aneurysm and myelopathy improvement. This report illustrates the first case of a non-hemorrhagic intramedullary aneurysm associated with CCJ-EDAVF successfully treated with direct surgery.

Carotid Micromesh Stent for the Cervical Carotid Artery Dissecting Aneurysm in a Patient with Vascular Eagle Syndrome.

OBJECTIVES: An elongated styloid process may cause vascular Eagle syndrome that includes cervical carotid artery (CCA) dissection with stenosis and aneurysm formation. There are only four reported cases with vascular Eagle syndrome-related CCA dissecting aneurysm treated with carotid artery stenting (CAS). This is the first report of applying a dual-layer nitinol micromesh stent (CASPER) for vascular Eagle syndrome-related CCA dissecting aneurysm. CASE PRESENTATION: A 38-year-old man presented with a sudden onset of aphasia and right hemiplegia. Cerebral angiography demonstrated the left CCA dissecting aneurysm. The superior trunk of the left middle cerebral artery (MCA) was also occluded, and emergent thrombectomy was performed. Computed tomography with angiography (CTA) revealed that a 33 mm-long styloid process compressed the CCA at the aneurysm formation. Three weeks later, a CASPER stent was applied for the CCA aneurysm under the flow reversal system. Immediately after stent placement, blood flow in the aneurysm became stagnant, and postoperative CTA demonstrated regression of the aneurysm. The aneurysm did not recur for 6 months with no styloid process resection. CONCLUSIONS: The dual-layer nitinol micromesh stent (CASPER) was useful to treat vascular Eagle syndrome-related CCA dissecting aneurysm.

[Posterior Subthalamic Area, Pallidothalamic Tract, and Pedunculopontine Nucleus:Deep Brain Stimulation Targets for Parkinson's Disease and Essential Tremor].

This article reviews the stereotactic targets in the posterior subthalamic area(PSA), fields H1/H2 of Forel(pallidothalamic tract), and the pedunculopontine nucleus(PPN)to complement the preceding articles on stereotactic and functional neurosurgery for movement disorders in the present issue of No Shinkei Geka. Two regions within the subthalamus, the PSA and fields H1/H2 of Forel, are the revisited stereotactic targets to treat movement disorders. Currently, the PSA is often utilized to treat essential tremor and various types of tremor. Fields H1/H2 of Forel are investigated as a target for magnetic resonance-guided focused ultrasound to treat motor symptoms and motor complications in patients with Parkinson's disease. For the past twenty years, the PPN has been investigated to treat refractory gait freezing and fall in patients with Parkinson's disease. These revisited and novel targets may be utilized as substitutes and complements for the present standard stereotactic targets.

Characteristics and outcomes of elderly patients with diffuse gliomas: a multi-institutional cohort study by Kansai Molecular Diagnosis Network for CNS Tumors.

INTRODUCTION: This study investigates the current state of clinical practice and molecular analysis for elderly patients with diffuse gliomas and aims to elucidate treatment outcomes and prognostic factors of patients with glioblastomas. METHODS: We collected elderly cases (≥ 70 years) diagnosed with primary diffuse gliomas and enrolled in Kansai Molecular Diagnosis Network for CNS Tumors. Clinical and pathological characteristics were analyzed retrospectively. Various factors were evaluated in univariate and multivariate models to examine their effects on overall survival. RESULTS: Included in the study were 140 elderly patients (WHO grade II: 7, III: 19, IV: 114), median age was 75 years. Sixty-seven patients (47.9%) had preoperative Karnofsky Performance Status score of ≥ 80. All patients underwent resection (gross-total: 20.0%, subtotal: 14.3%, partial: 39.3%, biopsy: 26.4%). Ninety-six of the patients (68.6%) received adjuvant treatment consisting of radiotherapy (RT) with temozolomide (TMZ). Seventy-eight of the patients (75.0%) received radiation dose of ≥ 50 Gy. MGMT promoter was methylated in 68 tumors (48.6%), IDH1/2 was wild-type in 129 tumors (92.1%), and TERT promoter was mutated in 78 of 128 tumors (60.9%). Median progression-free and overall survival of grade IV cases was 8.2 and 13.6 months, respectively. Higher age (≥ 80 years) and TERT promoter mutated were associated with shorter survival. Resection and adjuvant RT + TMZ were identified as independent factors for good prognosis. CONCLUSIONS: This community-based study reveals characteristics and outcomes of elderly glioma patients in a real-world setting. Elderly patients have several potential factors for poor prognosis, but resection followed by RT + TMZ could lengthen duration of survival.

Bridging veins and veins of the brainstem in microvascular decompression surgery for trigeminal neuralgia and hemifacial spasm.

OBJECTIVE In microvascular decompression surgery for trigeminal neuralgia and hemifacial spasm, the bridging veins are dissected to provide the surgical corridors, and the veins of the brainstem may be mobilized in cases of venous compression. Strategy and technique in dissecting these veins may affect the surgical outcome. The authors investigated solutions for minimizing venous complications and reviewed the outcome for venous decompression. METHODS The authors retrospectively reviewed their surgical series of microvascular decompression for trigeminal neuralgia and hemifacial spasm in patients treated between 2005 and 2017. Surgical strategies included preservation of the superior petrosal vein and its tributaries, thorough dissection of the arachnoid sleeve that enveloped these veins, cutting of the inferior petrosal vein over the lower cranial nerves, and mobilization or cutting of the veins of the brainstem that compressed the nerve roots. The authors summarized the patient characteristics, operative findings, and postoperative outcomes according to the vascular compression types as follows: artery alone, artery and vein, and vein alone. They analyzed the data using chi-square and 1-way ANOVA tests. RESULTS The cohort was composed of 121 patients with trigeminal neuralgia and 205 patients with hemifacial spasm. The superior petrosal vein and its tributaries were preserved with no serious complications in all patients with trigeminal neuralgia. Venous compression alone and arterial and venous compressions were observed in 4% and 22%, respectively, of the patients with trigeminal neuralgia, and in 1% and 2%, respectively, of those with hemifacial spasm (p < 0.0001). In patients with trigeminal neuralgia, 35% of those with artery and venous compressions and 80% of those with venous compression alone had atypical neuralgia (p = 0.015). The surgical cure and recurrence rates of trigeminal neuralgias with venous compression were 60% and 20%, respectively, and with arterial and venous compressions the rates were 92% and 12%, respectively (p < 0.0001, p = 0.04). In patients with hemifacial spasm who had arterial and venous compressions, their recurrence rate was 60%, and that was significantly higher compared to other compression types (p = 0.0008). CONCLUSIONS Dissection of the arachnoid sleeve that envelops the superior petrosal vein may help to reduce venous complications in surgery for trigeminal neuralgia. Venous compression may correlate with worse prognosis even with thorough decompression, in both trigeminal neuralgia and hemifacial spasm.

IntroMap: a signal analysis based method for the detection of genomic introgressions.

BACKGROUND: Breeding programs often rely on marker-assisted tests or variant calling of next generation sequence (NGS) data to identify regions of genomic introgression arising from the hybridization of two plant species. In this paper we present IntroMap, a bioinformatics pipeline for the screening of candidate plants through the application of signal processing techniques to NGS data, using alignment to a reference genome sequence (annotation is not required) that shares homology with the recurrent parental cultivar, and without the need for de novo assembly of the read data or variant calling. RESULTS: We show the accurate identification of introgressed genomic regions using both in silico simulated genomes, and a hybridized cultivar data set using our pipeline. Additionally we show, through targeted marker-based assays, validation of the IntroMap predicted regions for the hybrid cultivar. CONCLUSIONS: This approach can be used to automate the screening of large populations, reducing the time and labor required, and can improve the accuracy of the detection of introgressed regions in comparison to a marker-based approach. In contrast to other approaches that generally rely upon a variant calling step, our method achieves accurate identification of introgressed regions without variant calling, relying solely upon alignment.

Coaxial interleaved stimulation of the thalamus and subthalamus for treatment of Holmes tremor.

Holmes tremor is often treated with multiple deep brain stimulation (DBS) electrodes. The authors describe a novel technique to suppress the tremors by effectively utilizing a single electrode. A 16-year-old boy presented with severe right arm tremor following a midbrain injury. A DBS electrode was implanted into the ventral oralis nucleus of the thalamus (VO) and the subthalamic region. While individual stimulation of each target was ineffective, an interleaved dual stimulation of both targets has been effective for 6 years. Coaxial interleaved stimulation of the VO and the subthalamic region is useful for treating Holmes tremor. The video can be found here: https://youtu.be/tSwGh3vy68c .

[Treatment of Non-Traumatic Spinal Epidural Hematoma:A Report of Five Cases and a Systematic Review of the Literature].

Objective:Non-traumatic spinal epidural hematoma(SEH)is relatively rare. We report five cases of SEH, review the relevant literature, and discuss the current treatment strategies for non-traumatic SEH in Japan. Methods:Clinical data of cases with non-traumatic SEH treated at our institute from 2008 to 2015 were retrospectively analyzed. In addition, we identified the relevant literature using the Japan Medical Abstracts Society databases for peer-reviewed articles published from Jan 1, 1995 to Aug 31, 2015. The search terms "spinal", "epidural hematoma", and "non-traumatic OR spontaneous" were used. Treatment strategies were summarized according to the treatment criteria. Results:Five patients(1 man and 4 women;age, 59-86 years;mean age, 74 years)were treated for SEH. Hematomas were located in the cervical(n=1), cervicothoracic(n=2), thoracic(n=1), and thoracolumbar(n=1)regions. All patients suffered sudden neck and/or back pain followed by subsequent neurological deterioration. Four patients were under antithrombotic treatment, and underwent laminectomy and drainage of the hematoma due to severe and progressive neurological deficits. All patients demonstrated significant neurological recovery. Seventy-seven articles from domestic institutes and hospitals were identified. Their criteria for conservative and surgical treatments differed based on the time from the onset and severity. Conclusion:Five cases of non-traumatic SEH were treated successfully. Patients with moderate to severe neurological deficit need timely surgical management, while non-surgical treatment may be indicated in mild deficits. To standardize the optimal treatment for non-traumatic SEH, an appropriate assessment system incorporating the time from onset and severity of neurological impairment should be established.

[A Single-Stage Combined Supra- and Infra-Sellar Approach for Recurrent Large Pituitary Adenomas:Report of Two Cases].

Despite the recent technological advances in operative instruments and development of novel techniques for endoscopic skull-base surgeries, surgical treatment of primary or recurrent large/giant pituitary adenomas remains a challenge. Postoperative hemorrhage from the residual tumor and the associated impairment of the adjacent cranial nerve functions can cause severe morbidity. To manage such operative risks, a combined supra- and infra-sellar approach(CSISA)can be used as a surgical option for difficult-to-resect large/giant pituitary adenomas. We successfully performed a single-stage CSISA in two patients with large recurrent pituitary adenomas with favorable outcomes. Both patients had recurrent adenomas after multiple trans-sphenoidal surgeries and presented with visual impairment due to tumor regrowth. Each tumor had a maximum diameter of more than 4 cm. One tumor extended into the anterior skull base, while the other extended into the supra-sellar region with extremely lateral invasion. The CSISA helped surgeons visualize the tumors and the surrounding structures through a combination of different operative views. Subtotal resection was safely achieved in both cases, with no postoperative hemorrhage and deterioration of visual and pituitary function. The CSISA is useful not only for pituitary adenomas with anterior or lateral extension and multi-lobular growth, but also for certain cases with recurrent large/giant pituitary adenomas.

Assessment of head-mounted display for exoscopic neurosurgery.

Background: Head-mounted display (HMD) arises as an alternative display system for surgery. This study aimed to assess the utility of a stereoscopic HMD for exoscopic neurosurgery. Methods: The leading operator and assistants were asked to assess the various aspects of the HMD characteristics compared to the monitor display using a visual analog scale (VAS)-based questionnaire. The VAS score ranged from 0 to 10 (0, HMD was significantly inferior to the monitor; 5, HMD and monitor display were equal; and 10, HMD was significantly superior to the monitor). Results: The surgeons and assistants used and evaluated HMD in seven exoscopic surgeries: three tumor removal, one aneurysm clipping, one anterior cervical discectomy and fusion, and two cervical laminectomy surgeries. The leading operators' assessment of HMD-based surgery was not different from monitor-based surgery; however, the assistants evaluated the field of view, overall image quality, and the assisting procedure as better in MHD-based surgery than monitor-based surgery (P = 0.039, 0.045, and 0.013, respectively). Conclusion: HMD-based exoscopic neurosurgery can be performed at a similar quality as monitor-based surgery. Surgical assistants may benefit from using HMD-based surgery.

Surgical Nuances and Predictors of Requirement for Suprameatal Tubercle Removal in Microvascular Decompression for Trigeminal Neuralgia.

Objective Suprameatal tubercle (SMT), a bony prominence located above the internal acoustic meatus, is reported to impede the microscopic view during microvascular decompression (MVD) for trigeminal neuralgia (TN). For an enlarged SMT, removal of the SMT may be required in addition to the routine MVD to precisely localize the offending vessels. The objective of this study is to investigate the predictive factors influencing the requirement of SMT removal during trigeminal MVD. Methods We retrospectively reviewed 197 patients who underwent MVD for TN, and analyzed the correlation of the SMT height and other clinicosurgical data with the necessity to remove the SMT during MVD. The parameters evaluated in the statistical analyses included maximum SMT height, patient's clinical characteristics, surgical data including the type and number of offending vessels, and surgical outcomes. Results SMT removal was required for 20 patients among a total of enrolled 197 patients. In the univariate analysis, maximum SMT height, patient's age, and number (≥ 2) of offending vessels were associated with the requirement for SMT removal. Multivariate analysis with binary logistic regression revealed that the maximum SMT height and number (≥ 2) of offending vessels were significant factors influencing the necessity for SMT removal. A receiver operating characteristic curve analysis revealed that an SMT height ≥ 4.8 mm was the optimal cutoff value for predicting the need for SMT removal. Conclusion Large SMTs and the presence of multiple offending vessels are helpful in predicting the technical difficulty of trigeminal MVD associated with the necessity of SMT removal.

Risk of Bone Wax Migration During Retrosigmoid Craniotomy for Microvascular Decompression: Case-Control Study.

BACKGROUND AND OBJECTIVES: Bone wax is a flexible hemostatic agent commonly used for surgery in the posterior cranial fossa to control bleeding from the mastoid emissary vein. A large amount of bone wax can migrate into the sigmoid sinus through the mastoid emissary canal (MEC). We aimed to identify clinical factors related to intraoperative bone wax migration through the MEC during microvascular decompression (MVD) surgery, which may result in sigmoid sinus thrombosis. METHODS: We retrospectively collected the clinical data of patients with trigeminal neuralgia, hemifacial spasm, or trigeminal neuralgia accompanied by painful tic convulsif who underwent MVD. Basic information and the residual width and length (from the bone surface to the sigmoid sinus) of the MEC on computed tomography images were collected. We compared the collected clinical data between 2 groups of cases with and without intraoperative bone wax migration in the sigmoid sinus. RESULTS: Fifty-four cases with intraoperative bone wax migration and 187 patients without migration were enrolled. The t -test revealed significant differences in the width and length of the MEC ( P = .013 and P = .003, respectively). These variables were identified as significant factors in predicting intraoperative bone wax migration using multivariate logistic regression analysis. CONCLUSION: The large size of the MEC may be related to intraoperative bone wax migration into the sigmoid sinus in MVD. Neurosurgeons should be aware of these risks. Bone wax should be applied appropriately and hemostasis should be considered to control bleeding from the mastoid emissary vein in patients with a large MEC.

Intraventricular pituicytoma: illustrative case.

BACKGROUND: Pituicytoma is a rare glial neoplasm from pituicytes of the neurohypophysis or infundibulum. It occurs in the sella and suprasellar area, and it is extremely uncommon to observe intraventricular pituicytoma without affecting the infundibulum or infundibular recess. OBSERVATIONS: A 69-year-old man had suffered progressive dementia for 6 months. Magnetic resonance imaging revealed a solid, homogeneously enhancing mass with flow voids within the anterior third ventricle. The sella, suprasellar area, infundibulum, and infundibular recess were unaffected. The patient underwent a transcallosal transchoroidal approach, which ended in partial removal of the tumor due to significant tumoral bleeding. A second surgery resulted in its subtotal removal. The tumor had bipolar cells, and their nuclei were immunoreactive for thyroid transcription factor-1. A DNA methylation analysis corresponded to the methylation class of pituicytoma, granular cell tumor, and spindle cell oncocytoma. Pituicytoma was the diagnosis based on these results. A systematic review identified 5 intraventricular pituicytoma cases. LESSONS: Intraventricular pituicytoma can grow without involvement of the infundibulum or infundibular recess. The current case suggests that pituicytes of the hypothalamic tuber cinereum can also give rise to pituicytoma. Because of the hypervascular nature of intraventricular pituicytomas, it is imperative to control intraoperative bleeding with attention to the adjacent hypothalamus. https://thejns.org/doi/10.3171/CASE24247.

Lipocalin-type prostaglandin D synthase: a glymphopathy marker in idiopathic hydrocephalus.

Idiopathic normal pressure hydrocephalus in elderly people is considered a form of glymphopathy caused by malfunction of the waste clearance pathway, called the glymphatic system. Tau is a representative waste material similar to amyloid-ß. During neurodegeneration, lipocalin-type prostaglandin D synthase (L-PGDS), a major cerebrospinal fluid (CSF) protein, is reported to act as a chaperone that prevents the neurotoxic aggregation of amyloid-ß. L-PGDS is also a CSF biomarker in idiopathic normal pressure hydrocephalus and significantly correlates with tau concentration, age, and age-related brain white matter changes detected by magnetic resonance imaging. To investigate this glymphopathy, we aimed to analyze white matter changes and contributing factors in vivo and their interactions ex vivo. Cerebrospinal tap tests were performed in 60 patients referred for symptomatic ventriculomegaly. Patients were evaluated using an idiopathic normal pressure hydrocephalus grading scale, mini-mental state examination, frontal assessment battery, and timed up-and-go test. The typical morphological features of high convexity tightness and ventriculomegaly were measured using the callosal angle and Evans index, and parenchymal white matter properties were evaluated with diffusion tensor imaging followed by tract-based spatial statistics. Levels of CSF biomarkers, including tau, amyloid-ß, and L-PGDS, were determined by ELISA, and their interaction, and localization were determined using immunoprecipitation and immunohistochemical analyses. Tract-based spatial statistics for fractional anisotropy revealed clusters that positively correlated with mini-mental state examination, frontal assessment battery, and callosal angle, and clusters that negatively correlated with age, disease duration, idiopathic normal pressure hydrocephalus grading scale, Evans index, and L-PGDS. Other parameters also indicated clusters that correlated with symptoms, microstructural white matter changes, and L-PGDS. Tau co-precipitated with L-PGDS, and colocalization was confirmed in postmortem specimens of neurodegenerative disease obtained from the human Brain Bank. Our study supports the diagnostic value of L-PGDS as a surrogate marker for white matter integrity in idiopathic normal pressure hydrocephalus. These results increase our understanding of the molecular players in the glymphatic system. Moreover, this study indicates the potential utility of enhancing endogenous protective factors to maintain brain homeostasis.

Prediction of MGMT promotor methylation status in glioblastoma by contrast-enhanced T1-weighted intensity image.

Background: The study aims to explore MRI phenotypes that predict glioblastoma's (GBM) methylation status of the promoter region of MGMT gene (pMGMT) by qualitatively assessing contrast-enhanced T1-weighted intensity images. Methods: A total of 193 histologically and molecularly confirmed GBMs at the Kansai Network for Molecular Diagnosis of Central Nervous Tumors (KANSAI) were used as an exploratory cohort. From the Cancer Imaging Archive/Cancer Genome Atlas (TCGA) 93 patients were used as validation cohorts. "Thickened structure" was defined as the solid tumor component presenting circumferential extension or occupying >50% of the tumor volume. "Methylated contrast phenotype" was defined as indistinct enhancing circumferential border, heterogenous enhancement, or nodular enhancement. Inter-rater agreement was assessed, followed by an investigation of the relationship between radiological findings and pMGMT methylation status. Results: Fleiss's Kappa coefficient for "Thickened structure" was 0.68 for the exploratory and 0.55 for the validation cohort, and for "Methylated contrast phenotype," 0.30 and 0.39, respectively. The imaging feature, the presence of "Thickened structure" and absence of "Methylated contrast phenotype," was significantly predictive of pMGMT unmethylation both for the exploratory (p = .015, odds ratio = 2.44) and for the validation cohort (p = .006, odds ratio = 7.83). The sensitivities and specificities of the imaging feature, the presence of "Thickened structure," and the absence of "Methylated contrast phenotype" for predicting pMGMT unmethylation were 0.29 and 0.86 for the exploratory and 0.25 and 0.96 for the validation cohort. Conclusions: The present study showed that qualitative assessment of contrast-enhanced T1-weighted intensity images helps predict GBM's pMGMT methylation status.

Functionality and Usability of the Exoscope in Microvascular Decompression for Hemifacial Spasm and Trigeminal Neuralgia.

BACKGROUND: Studies on the functionality and usability of the exoscope in neurosurgical procedures against surgical microscopes (SMs) are limited. This study aimed to examine the functionality and usability of the exoscope during microvascular decompression (MVD) surgery. METHODS: Seven neurosurgeons evaluated the usefulness of a 4 K, 3-dimension digital exoscope in MVD by answering a questionnaire. The questionnaire inquired about the functionality and usability of the exoscope by utilizing a visual analog scale (VAS; 1-10). A score of 5 on VAS was equivalent to the corresponding quality of the SM. The learning effect of the exoscope was evaluated using mean VAS scores in the first and last 3 cases for each neurosurgeon. RESULTS: The functionality of the exoscope in MVD was superior to that in SM (P < 0.001). In the last 3 surgeries, the mean VAS scores of the exoscope were excellent in terms of ease of arm handling, exchange of surgical instruments, ease of surgical procedure, and intraoperative physical stress. The mean VAS scores of the exoscope in intraoperative asthenopia were significantly higher than those of the SM (P < 0.001). No statistical significance was found in operation time, discharge outcome, and 1-year post-surgery outcome between MVD performed using the exoscope and SM. CONCLUSIONS: Neurosurgeons may experience reduced stress levels during MVD when using the exoscope. As the outcome of MVD using the exoscope did not demonstrate a statistical difference compared with MVD using the SM, the exoscope may prove to be a useful tool for performing MVD.

Resolution of Visual Field Defect in Macroprolactinoma After Treatment With Cabergoline.

We report the case of a 49-year-old woman presenting with amenorrhea and progressive visual field defect for one month. Endocrinological workup revealed a high concentration of serum prolactin, and magnetic resonance imaging (MRI) showed pituitary macroadenoma with extrasellar extension as well as compression of optic nerves. Treatment with a dopamine agonist, cabergoline, for eight weeks led to the resolution of the visual field defect accompanied by a rapid decrease in the serum prolactin level. Follow-up MRI three months after the initial diagnosis revealed alleviation of visible mechanical compression of the optic chiasm by the tumor. We considered that the absence of retinal nerve damage and prompt initiation of cabergoline contributed to the rapid recovery of the visual acuity.

Subthalamic nucleus deep brain stimulation restores normal rapid eye movement sleep in Parkinson's disease.

BACKGROUND: In Parkinson's disease, sleep disturbance is a common occurrence. METHODS: We evaluated sleep in 10 patients with Parkinson's disease (age, 57.5 ± 9.8 years; disease duration, 12.3 ± 2.7 years) before and after subthalamic nucleus deep brain stimulation using the Parkinson's disease sleep scale and polysomnography. RESULTS: Their total sleep scale scores and daytime sleepiness subscale scores significantly improved after subthalamic nucleus-deep brain stimulation. The novel findings from this study significantly increased normal rapid eye movement sleep, and decreased abnormal rapid eye movement sleep without atonia after deep brain stimulation in patients with Parkinson's disease. The improved total sleep scale score correlated with decreased wakefulness after sleep onset. Moreover, improved daytime sleepiness correlated with increased normal rapid eye movement sleep time. Sleep improvement did not significantly correlate with resolution of motor complication or reduced dopaminergic dosages. CONCLUSIONS: Subthalamic nucleus-deep brain stimulation may have beneficial effects on sleep disturbance in advanced Parkinson's disease by restoring sleep architecture and normal rapid eye movement sleep.

Thalamic Deep Brain Stimulation for Refractory Atypical Tremor after Encephalitis of Unknown Etiology: A Case Report.

Tremor associated with encephalitis is usually transient and rarely becomes chronic and refractory. Treatment for such tremor using deep brain stimulation (DBS) has not yet been reported. We report an uncommon case of chronic tremor after encephalitis of unknown etiology and its outcome treated with thalamic DBS. A 47-year-old man presented with a 6-month history of medically refractory tremor after non-infectious and probable autoimmune encephalitis. The patient showed an atypical mixture of resting, postural, kinetic, and intention tremor. The tremor significantly disabled the patient's activities of daily life (ADL). The patient underwent bilateral thalamic DBS surgery. DBS leads were placed to cross the border between the ventralis oralis posterior (Vop) nucleus and ventralis intermedius (Vim) nucleus of the thalamus. Stimulation of both the Vop and Vim using the bipolar contacts controlled the mixed occurrence of tremor. The ADL and performance scores on The Essential Tremor Rating Assessment Scale (TETRAS) improved from 47 to 0 and from 44 to 9, respectively. The therapeutic effects have lasted for 24 months. Administration of combined Vop and Vim DBS may control uncommon tremor of atypical etiology and phenomenology.