Localization and symptoms associated with removal of negative motor area during awake surgery

BACKGROUND

In awake surgery, cortical mapping may identify the negative motor area (NMA). However, since speech arrest occurs regardless of whether the NMA or the frontal language area (FLA) is stimulated, the presence of speech arrest alone does not distinguish the NMA from the FLA. Furthermore, the exact location and function of the NMA is not well understood. The purpose of this study was to more accurately locate the NMA in a group of cases in which the NMA and FLA could be identified in different brain gyri, and to describe symptoms in cases in which the NMA was removed.

METHODS

There were 18 cases of awake surgery at our institution between 2000 and 2013 in which cortical stimulation allowed identification of FLA and NMA in separate brain gyri. In these cases, the pre- and post-removal mapping results were projected onto a 3D model postoperatively. We investigated the symptoms and social rehabilitation in a case in which the tumour invaded the same brain gyrus as the NMA and the NMA had to be resected in combination with the tumour.

RESULTS

In cases where the NMA and FLA could be identified in different brain gyri, NMA was localized inferior to the precentral gyrus in all cases. In four cases where NMA was removed with the tumour, apraxia of speech was observed during the surgery; the same symptoms persisted after it, but it improved within a few months, and the patients were able to return to work.

CONCLUSION

In cases where NMA and FLA could be identified separately by awake mapping, the NMA was commonly localized inferior to the precentral gyrus. When NMAs were resected in combination with tumour invasion, they did not lead to serious, long-term complications.

Systemic Metastasis of Pediatric Diffuse High-grade Astrocytoma: A Case Report

Extracranial brain tumor metastases are extremely rare. The etiology, pathophysiology, and clinical progression of systemic metastatic brain cancer remain to be elucidated. We encountered a case of pediatric diffuse high-grade astrocytoma in a four-year-old girl with subcutaneous and lymph node metastases. Numerous metastatic lesions emerged, progressed rapidly, and were difficult to manage despite temozolomide (TMZ) administration. The patient underwent repeated surgical resection for these lesions. Conversely, the primary intracranial lesions responded well to TMZ for some time. However, the patient died 15 months after the initial diagnosis. Extracranial metastasis and highly varying effects of chemotherapy were the characteristic clinical features in this case. Our analysis did not reveal definitive histopathological and molecular factors contributing to this presentation. The lack of notable molecular pathological features illustrates the unpredictability of glioma metastasis, and the treatment for extracranial metastasis remains unknown. A gene panel analysis revealed several genetic aberrations, including PDGFRA, PIK3CA, and NBN mutations. As it is impossible to resect all frequently and rapidly progressing lesions, we stress that the prognosis of metastatic brain tumors is undoubtedly poor if these tumors are refractory to existing treatments, including chemotherapy.

Endoscope-assisted Trans-lamina Terminalis Resection of Chordoid Glioma at the Third Ventricle: A Case Report

As per the 2021 World Health Organization (WHO) Classification of Tumors of the Central Nervous System, chordoid glioma (CG) is defined as a slow-growing glial neoplasm categorized as grade II tumor. This tumor is primarily located in the anterior part of the third ventricle, often adheres to important surrounding structures, and is hemorrhagic in nature. Therefore, dissecting this tumor is extremely difficult. In this study, we present the case of a 44-year-old man who initially complained of mild headache and was diagnosed with a homogeneous gadolinium-enhanced lesion in the third ventricle via magnetic resonance imaging. The pathological diagnosis based on his biopsy at the previous hospital was CG. The patient demonstrated no neurological deficit at that time, but the tumor had gradually grown, hydrocephalus appeared 2 years after the tumor was detected, and the patient developed short memory disorder and daytime sleepiness. We resected the tumor via the anterior interhemispheric trans-lamina terminalis approach using a microscope and an endoscope. The residual tumor at the blind spot of the microscopic view was resected under an angled rigid endoscopic view using dedicated tools for transsphenoidal surgery. The tumor was grossly resected, and the histopathological diagnosis was CG. Postoperative neurological findings included slight memory disorder and hypothalamic adrenal dysfunction. No tumor recurrence was reported 3 years post resection. The endoscope-assisted anterior interhemispheric trans-lamina terminalis approach was determined useful for CG resection with minimal surgical complications and without tumor recurrence.

Difference in Clinical Phenotype, Mutation Position, and Structural Change of RNF213 Rare Variants Between Pediatric and Adult Japanese Patients with Moyamoya Disease

It is unclear how rare RNF213 variants, other than the p.R4810K founder variant, affect the clinical phenotype or the function of RNF213 in moyamoya disease (MMD). This study included 151 Japanese patients with MMD. After performing targeted resequencing for all coding exons in RNF213, we investigated the clinical phenotype and statistically analyzed the genotype-phenotype correlation. We mapped RNF213 variants on a three-dimensional (3D) model of human RNF213 and analyzed the structural changes due to variants. The RNF213 p.R4810K homozygous variant, p.R4810K heterozygous variant, and wild type were detected in 10 (6.6%), 111 (73.5%), and 30 (19.9%) MMD patients, respectively. In addition, 15 rare variants were detected in 16 (10.6%) patients. In addition to the influence of the p.R4810K homozygous variant, the frequency of cerebral infarction at disease onset was higher in pediatric patients with other rare variants (3/6, 50.0%, P = 0.006) than in those with only the p.R4810K heterozygous variant or with no variants (2/51, 3.9%). Furthermore, on 3D modelling of RNF213, the majority of rare variants found in pediatric patients were located in the E3 module and associated with salt bridge loss, contrary to the results for adult patients. The clinical phenotype of rare RNF213 variants, mapped mutation position, and their predicted structural change differed between pediatric and adult patients with MMD. Rare RNF213 variants, in addition to the founder p.R4810K homozygous variant, can influence MMD clinical phenotypes or structural change which may contribute to the destabilization of RNF213.

Biplane fluoroscopy-guided percutaneous spinal cord stimulation

OBJECTIVE

Fluoroscopy is useful for spinal cord stimulation (SCS) lead placement. We employed biplane fluoroscopy for SCS lead placement. In this study, we sought to confirm the validity of using biplane fluoroscopy for SCS lead placement and to establish whether biplane fluoroscopy safely reduces the duration of surgery.

METHODS

Clinical data were retrospectively collected from the medical records of patients who underwent SCS lead placement under local anesthesia from 2015 to 2022. The duration of the surgical phase and the total radiation exposure time per case were recorded.

RESULTS

Forty-six patients underwent percutaneous SCS lead implantation. Recording was completed in 41 cases: one lead was placed in 13 cases and two leads were placed in 28 cases. Monoplane and biplane fluoroscopy was used in 15 and 26 patients, respectively. Although the type of fluoroscopy did not significantly affect the mean duration of the surgical phase in patients in which one lead was placed, biplane fluoroscopy was associated with a significant reduction in the mean duration of the surgical phase in patients that underwent placement of two leads (P=0.002). No significant differences in the total radiation exposure time were observed between patients in the monoplane and biplane fluoroscopy groups that were implanted with one (P=0.21) or two leads (P=0.62).

CONCLUSIONS

The use of biplane fluoroscopy reduced the duration of surgery necessary for the placement of two SCS leads. Biplane fluoroscopy represents a practical and safe adjustment to the current practice of SCS lead implantation.

Increase in serum vimentin levels in patients with glioma and its correlation with prognosis of patients with glioblastoma

Early diagnosis of glioma is of great value to improve prognosis. We focused on serum vimentin levels as a useful biomarker for preoperative diagnosis. The aim of this study was to determine whether serum vimentin levels in patients with glioma are significantly higher than those of healthy adult volunteer and whether the serum vimentin level is associated with overall survival (OS) in patients with glioblastoma (GBM). This study included 52 consecutive patients with newly diagnosed glioma and a control group of 13 healthy adult volunteers. We measured serum vimentin levels in blood samples obtained from patients with glioma preoperatively and a control group. Furthermore, we investigated the correlation between serum vimentin levels and OS in patients with GBM. The serum vimentin levels of patients with glioma were significantly higher than those of the control group. The serum vimentin level of 2.9 ng/ml was the optimal value for differentiating patients with glioma from the control group with a sensitivity of 92.3% and specificity of 88.5%. The serum vimentin levels correlated significantly with immunoreactivity for survivin. In 27 patients with GBM, serum vimentin levels (cutoff value, median value 53.3 ng/ml) correlated with OS in univariate and multivariate analyses. Our study revealed that serum vimentin levels of patients with glioma are significantly higher than those of the control group. Therefore, we believe that serum vimentin level might be a useful and practical biomarker for preoperative diagnosis of glioma. Furthermore, high serum vimentin levels correlated significantly with shorter OS in patients with GBM.

Optimal guiding catheter position during advancement of the guiding catheter into the carotid artery from the aortic arch via transfemoral approach

BACKGROUND

Guiding catheter (GC) advancement into the target carotid artery is a crucial step in neuroendovascular therapy. In difficult anatomies, alternative methods have been reported to overcome difficult carotid access for swift GC advancement. However, studies focusing on the positional relationship between the GC and inner catheter (IC) at the aortic arch are lacking.

METHODS

We evaluated the impact of the positional relationship between the GC and IC on whether the GC position affects catheter support or system straightening. We retrospectively reviewed 89 patients who underwent neuroendovascular therapy. We assessed the time to carotid access across difficult arch anatomies. The GC position was divided into Position 1, descending aorta level; Position 2, aortic arch level; and Position 3, origin of the left common carotid artery or innominate artery. We also evaluated the GC support and straightening effects in an in vitro vascular model study.

RESULTS

The coaxial catheter flexion angle at the aortic arch was significantly larger when the GC was set to Position 3 (p < 0.0001). A significantly shorter time to carotid access was observed with Positions 2 and 3 than with Position 1 in the difficult arch anatomy group. In the in vitro vascular model evaluation, the catheter support effect significantly increased as the GC position became closer to the IC tip (p < 0.0001) and straightening effect significantly increased as the GC moved to Position 2 from Position 1 (p < 0.0001).

CONCLUSION

During GC advancement, the GC positional relationship changed the support of the coaxial system with system straightening. The optimal GC position, Position 3, facilitated swift GC advancement.

Jaw Claudication Caused by Atherothrombotic External Carotid Artery Occlusion: A Case Report

Jaw claudication is a common symptom of giant cell arteritis (GCA), although atherothrombotic external carotid artery (ECA) occlusion is also known to cause jaw claudication. The patient was a 75-year-old male who experienced severe right jaw pain while chewing solid food. Magnetic resonance (MR) angiography showed right ECA occlusion. Based on laboratory tests and contrast-enhanced computed tomography (CT) angiography, atherothrombosis, not GCA, was suspected to be the cause of jaw claudication. Following conservative therapy with cilostazol, the pain was gradually alleviated in two months, and subsequent MR angiography after four months showed blood flow in the stenosed right ECA. The symptom completely disappeared in six months. Based on a previous report, we expected that jaw claudication will be ameliorated due to the development of collateral supply; however, spontaneous ECA recanalization caused improvement of symptoms in this case.

De Novo Radicular Arteriovenous Fistula After Treatment of Spinal Arteriovenous Fistula: A Case Report and Literature Review

De novo spinal dural arteriovenous fistulas (AVFs) have been reported as metachronous AVFs However, metachronous spinal AVFs are extremely rare, and their pathogenesis remains uncertain. We report a case of de novo radicular AVF (RAVF) following treatment for spinal AVF at the craniocervical junction (CCJ). We also reviewed the literature and discussed the pathogenesis of metachronous spinal AVF. A 64-year-old male patient diagnosed with spinal AVF at the CCJ supplied from the right C1 segmental artery was treated with Onyx-18 (eV3 Inc, CA, USA) trans-arterial embolization, resulting in partial occlusion. Angiography showed a slight residual shunt two weeks after the embolization without another shunt lesion. A five-year follow-up spinal angiography showed de novo RAVF at the C4 level and complete occlusion of the first AVF. The second AVF was not treated because it was asymptomatic, and the patient remained asymptomatic. De novo RAVF was found to develop five years after the embolization of a CCJ-spinal AVF in a patient. This is the first case of de novo RAVF post-treatment of a spinal AVF. This case demonstrated that RAVF could develop as an acquired disease.

A multicenter, randomized, placebo-controlled phase IIb trial of an autologous formalin-fixed tumor vaccine for newly diagnosed glioblastomas

OBJECTIVE

An autologous formalin-fixed tumor vaccine (AFTV) derived from resected glioblastoma (GBM) tissue can be used against unidentified tumor antigens. Thus, the authors conducted a multicenter double-blind phase IIb trial to investigate the efficacy of an AFTV.

METHODS

Eligible patients were adults with supratentorial GBMs, 16-75 years of age, with Karnofsky Performance Scale (KPS) scores ≥ 60%, and no long-term steroid administration. An AFTV comprising fixed paraffin-embedded tumor tissue with immune adjuvants or an identical placebo without fixed tumor tissue was injected intradermally over three courses before and after chemoradiotherapy. The primary and secondary end points were overall survival (OS), progression-free survival (PFS), and 3-year survival rate.

RESULTS

Sixty-three patients were enrolled. The average patient age was 61 years. The median KPS score was 80%, and the median resection rate was 95%. The full analysis set of 57 patients indicated no significant difference in OS (p = 0.64) for the AFTV group (median OS 25.6 months, 3-year OS rate 38%) compared with the placebo group (31.5 months and 41%, respectively) and no difference in PFS (median PFS 13.3 months in both groups, p = 0.98). For patients with imaging-based total tumor removal, the 3-year PFS rate was 81% in the AFTV group versus 46% in the placebo group (p = 0.067), whereas the 3-year OS rate was 80% versus 54% (p = 0.16), respectively. Similar results were obtained in the p53-negative subgroups. Severe adverse effects were not observed.

CONCLUSIONS

The AFTV may have potential effects in certain patient subgroups. A phase III study for patients with total tumor removal remains warranted to confirm these findings. Clinical trial registration no.: UMIN000010602 (UMIN Clinical Trials Registry).

Application of protective superficial temporal artery to middle cerebral artery bypass through the lateral supraorbital approach: Technical note

OBJECTIVE

The lateral supraorbital (LSO) approach is a minimally invasive craniotomy widely used in the surgical treatment of intracranial aneurysms (IAs). A protective bypass is considered a safety measure in high-risk and complex clipping procedures to maintain distal cerebral flow. However, the protective bypass has so far only been applied through a pterional or larger craniotomy. We aimed to describe the characteristics of the superficial temporal artery to middle cerebral artery (STA-MCA) bypass through the LSO craniotomy to treat complex IAs.

METHODS

We retrospectively identified six patients with complex IAs who underwent clipping and a protective STA-MCA bypass through the LSO approach between January 2016 and December 2020. The STA donor artery was harvested through the same curvilinear skin incision with a small extension, and it was anastomosed to the opercular segment of the MCA. Subsequently, aneurysm clipping followed standardized steps.

RESULTS

Anastomosis was successful in all patients. Despite requiring temporary occlusion of the parent artery, all aneurysms were successfully clipped without any neurological deterioration.

CONCLUSIONS

A protective STA-MCA bypass is feasible through the LSO approach with certain technical modifications. This technique helps protect distal cerebral flow for safe clip placement in the treatment of complex IAs with the associated benefits of a less invasive craniotomy.

Clinical Features of Pituitary or Parasellar Tumor Onset with Cranial Nerve Palsy: Surgical Intervention Considerations

OBJECTIVE

This study aimed to clarify the symptoms of pituitary or parasellar tumor onset with cranial nerve palsy (CNP) and to improve our knowledge of this rare symptom and its most appropriate treatment.

METHODS

Among 1281 patients with pituitary or parasellar tumors surgically treated from 2003 to 2020, 30 cases (2.34%; 15 men and 15 women; mean age: 55.6 years, range: 6-83 years) first presenting with CNP were reviewed to evaluate the neurological symptoms, histological diagnosis, interval from onset to surgery, and time before complete CNP recovery.

RESULTS

Pathological diagnoses comprised 17 pituitary adenomas, including 10 pituitary apoplexies and 4 adrenocorticotropic hormone-positive adenomas, and 13 other tumors, including 3 chordomas, 2 xanthogranulomas, 2 malignant lymphomas, 2 metastatic tumors, 1 Rathke cleft cyst, 1 plasmacytoma, 1 craniopharyngioma, and 1 neuroendocrine carcinoma. The mechanisms causing CNP were pituitary apoplexy (n = 10), cranial nerve compression or involvement (n = 17), and inflammatory changes (n = 9). As the first manifestation, 20 (66.7%) patients presented with oculomotor nerve palsy, 2 (6.7%) with trochlear nerve palsy, and 13 (43.3%) with abducens nerve palsy. Full recovery of CNP was obtained in 25 patients (83.3%) after surgery alone and in 2 patients (6.7%) after adjuvant therapy. Early surgery provided no significant difference in full recovery rates although it reduced the time to reach full recovery.

CONCLUSIONS

It is critical to determine the mechanisms of CNP and intervene surgically to improve symptoms, shorten the duration of the disorder, prevent relapses, and obtain the correct pathological diagnosis to select the proper adjuvant therapy.

Gamma Knife Thalamotomy for Essential Tremor: A Retrospective Analysis

BACKGROUND

Gamma knife (GK) thalamotomy has been used as a treatment option for essential tremor (ET). Numerous studies on GK use in ET treatment have reported more varied responses and complication rates.

METHODS

Data from 27 patients with ET who underwent GK thalamotomy were retrospectively analyzed. The Fahn-Tolosa-Marin Clinical Rating Scale for Tremor, handwriting, and spiral drawing were evaluated. Postoperative adverse events and magnetic resonance imaging findings were also evaluated.

RESULTS

The mean age at GK thalamotomy was 78.1 ± 4.2 years. The mean follow-up period was 32.5 ± 19.4 months. The preoperative postural tremor, handwriting, and spiral drawing scores were 3.4 ± 0.6, 3.3 ± 1.0, and 3.2 ± 0.8, respectively, all of which showed significant improvements to 1.5 ± 1.2 (55.9% improvement, P < 0.001), 1.4 ± 1.1 (57.6% improvement, P < 0.001), and 1.6 ± 1.3 (50% improvement, P < 0.001), respectively, at the available final follow-up evaluations. Three patients presented with no improvement in tremor. Six patients presented with adverse effects, including complete hemiparesis, foot weakness, dysarthria, dysphagia, lip numbness, and finger numbness, at the final follow-up period. Two patients presented with serious complications, including complete hemiparesis due to massive widespread edema and chronic encapsulated expanding hematoma. One patient died of aspiration pneumonia following severe dysphagia secondary to chronic encapsulated expanding hematoma.

CONCLUSIONS

GK thalamotomy is an efficient procedure for treating ET. Careful treatment planning is necessary to reduce complication rates. The prediction of radiation complications will increase the safety and effectiveness of GK treatment.

Bilateral symptomatic large cavernous carotid artery aneurysms treated by extracranial-intracranial bypass with parent artery occlusion

Bilateral large cavernous sinus internal carotid aneurysms (CCAs) occur very rarely. While the choice of treatment method is important, the timing of contralateral side treatment is equally important. We herein report the case of a 72-year-old woman who presented with progressive bilateral visual impairment and was treated by two-stage. First, the left CCAs had been treated, and the aneurysm was thrombosed, but her left visual acuity did not recover; the right CCA was becoming larger 2 years later, and her right visual acuity began worsening. The right CCAs was treated by almost same method. Her right visual acuity improved compared with the second preoperative findings. Our case findings suggest the importance of considering the appropriate timing to avoid symptom aggravation in patients with bilateral CCAs.

Improvement of obsessive-compulsive disorder after pallidothalamic tractotomy for cervical dystonia

A 30-year-old woman with tardive dystonia in the cervical region from long-term antipsychotic meds was treated with radiofrequency ablation of the right pallidothalamic tract in the fields of Forel. The patient showed improvement in both cervical dystonia and obsessive-compulsive disorder after the procedure, with 77.4% improvement in cervical dystonia and 86.7% improvement in obsessive-compulsive disorder. Although the treatment site in this case was intended to treat cervical dystonia, the lesion was located in the optimal stimulation network for both obsessive-compulsive disorder and cervical dystonia, suggesting that neuromodulation of this region could potentially treat both simultaneously.

[Intraoperative Visual Evoked Potential]

In neurosurgery, the intraoperative visual evoked potential(VEP)has recently been used for the management of anterior skull base and parasellar tumors related to the optic pathways to prevent postoperative visual complications. We used light emitting diode photo-stimulation thin pad and stimulator(Unique Medical, Japan). We also recorded the electroretinogram(ERG)simultaneously to exclude technical errors. VEP is defined as an amplitude between the maximum positive wave at 100 ms(P100)and the prior negative wave(N75). In intraoperative VEP monitoring, reproducibility of VEP should be ascertained, particularly in patients with preoperative advanced visual impairment and an intraoperative diminished amplitude. Furthermore, a 50% reduction in the amplitude is critical. In such cases, we should consider suspending or changing surgical manipulation. We have not clearly verified the relationship between the absolute intraoperative VEP value and postoperative visual function. Mild peripheral visual field defects cannot be detected in the present intraoperative VEP system. However, intraoperative VEP with ERG monitoring can serve as a real-time warning to guide surgeons to avoid postoperative visual impairment. We should comprehend the principles, characteristics, disadvantages, and limitations of intraoperative VEP monitoring for reliable and effective utilization.

Postsurgical dural supply to the spinal cord arteriovenous malformation in spinal arteriovenous metameric syndrome

Dural supply from the external carotid system in cerebral arteriovenous malformations (AVMs) is well known, but actual angiographic evidence of dural supply to spinal cord AVMs (SCAVMs) has not been reported. Here, we report a case of dural supply to the conus SCAVM in the spinal arteriovenous metameric syndrome segment 25-30. Thirteen years after spinal surgery (T12-L2 laminoplasty), spinal angiography showed multiple dural supplies from the dorsal somatic branches, prelaminar arteries, and radiculomeningeal arteries to the SCAVM at the level of the previous spinal surgery. To the best of our knowledge, this is the first reported case with dural supply to the spinal cord. This case demonstrates that the extradural and extraspinal branches can supply the spinal cord in rare instances of spinal dural adhesions following repeated hemorrhages and surgical intervention under a metameric link background.

Efficacy of the pedicle trapezius muscle flap for the multisurgical removal of pediatric posterior fossa anaplastic ependymoma

OBJECTIVE

Exceedingly refractory, pediatric anaplastic ependymoma in many cases requires multisurgical removal. The high risk of poor wound healing and CSF leakage especially at the posterior fossa make this tumor difficult to treat.

CASE

A 9-year-old girl has had 4th ventricular anaplastic ependymoma since the age of 3. She experienced tumor removal 8 times including 4 posterior fossa craniotomies because tumors were disseminated not only to the posterior fossa but also to the cerebral hemispheres. She also underwent a dermal graft using a free flap. She experienced CSF leaks and meningitis frequently because the wound healing was poor. We performed a dermal flap closure using a pedicle trapezius muscle flap with a plastic surgeon when we performed the 5th tumor removal.

RESULT

We achieved complete wound closure in spite of broad deficiencies in subcutaneous and epidermal tissues. After that, recurrences of posterior fossa tumors presented within a short term, and tumor removal via an incision of a pedicle trapezius muscle flap was performed without recurrence of CSF leaks and meningitis.

DISCUSSION AND CONCLUSION

For the first time, we are able to report on the efficacy of using the pedicle trapezius muscle flap for multisurgical removal of pediatric posterior fossa anaplastic ependymoma. The muscle flap was found to be effective because of the multiple surgeries expected, and the pedicle trapezius muscle flap was found to be resilient to multiple surgical procedures. Although advantageous, the dorsal scapular artery which is required for flap creation is actually difficult to harvest. Compared to a flee flap, the pedicle trapezius muscle flap maintains vascular supply. Furthermore, this technique has the possibility of being applied to defective dura mater closure that cannot be watertight due to multiple surgeries. However, it is very important to inform the patient's family not only about the improved efficacy of surgery, but also to raise awareness on consequential cosmetic issues.

Selective surgical mamillo-thalamic tract disconnection in hypothalamic hamartoma results in complete disappearance of gelastic seizures

Hypothalamic hamartoma is a less common condition characterized by the several types of epileptic seizures including the gelastic type. It is reported that gelastic seizures are resistant to medical treatment with anticonvulsants, while stereotactic thermocoagulation or Gamma Knife radiosurgery are effective for seizure control. Here, we report an individual case where direct surgical resection disconnecting hypothalamic hamartoma from mammillothalamic tract resulted in complete disappearance of gelastic seizures without deterioration of cognitive function. A 6-year-old boy developed gelastic seizures at the age of 2 and suffered from precocious puberty. Anticonvulsants including carbamazepine and zonisamide failed to control seizures. The patient underwent direct division of the mammillothalmic tract by removal of hypothalamic hamartoma partially via anterior interhemispheric approach. It was observed that gelastic seizures disappeared completely after the surgical treatment without any endocrine and cognitive dysfunction for a follow-up period of 14 years. The mammillothalamic tract which connects anterior nucleus of thalamus and mammillary bodies plays a key role in gelastic seizures related to hypothalamic hamartoma. In this case, we disconnected the hamartoma specifically from the mammillary bodies and not from the rest of hypothalamus. Effectively, it enabled permanent control of seizures. This result shows that fibers connecting other hypothalamic structures and the dorsomedial nucleus of thalamus are not involved in gelastic seizure propagation from the hypothalamic hamartoma. When surgical treatment of hypothalamic hamartomas is performed it has high morbidity associated with hypothalamic disorders. Therefore, disconnection between hypothalamic hamartoma and mammillary bodies presents a possibility of reducing hypothalamic damage. Surgical disconnection between hamartoma and mammillothalamic tract carries minimal hypothalamic injury risk and our results suggest that it has the potential of seizure control for intractable gelastic seizures with less complications.

Analysis of Factors Influencing Delayed Presentation in Japanese Patients with Subarachnoid Hemorrhage

OBJECTIVE

Some aneurysmal subarachnoid hemorrhage (SAH) patients are delayed in their presentation. This can cause a washout of the subarachnoid hematoma and a potential misdiagnosis. As a result, they may suffer rerupture of the aneurysm and preventable deterioration. We investigated the factors that influence delayed SAH presentation.

METHODS

Aneurysmal SAH patients treated at 9 stroke centers from 2002 to 2020 were included. Age, gender, pre-SAH modified Rankin scale, World Federation of Neurological Surgeons grade, Fisher group, day of presentation, aneurysm treatment method, past history of cerebral stroke, comorbidity of hypertension and/or diabetes mellitus, and modified Rankin scaleat discharge were assessed retrospectively. We formed 2 groups based on the day of presentation after the onset of SAH: day 0-3 (early) and other (delayed). Logistic regression analyses detected the factors that influenced the day of presentation and outcome for SAH. A P- value <0.05 was considered significant.

RESULTS

Delayed presentation comprised 282 cases (6.3%) of 4507 included cases. Logistic regression analyses showed that patients in an urban area, of male gender, low WFNS grade and low Fisher group correlated significantly with a delayed presentation. But delayed presentation did not influence outcome at discharge.

CONCLUSIONS

Area of residency and gender correlated with delayed presentation after SAH in Japan. Urbanization, male gender, and mild SAH lead patients to delay presentation. The factors underlying these tendencies will be analyzed in a future prospective study.