Incidence of Cerebral Cavernous Malformation-Related Epilepsy in Children: A Single Center Survey.

INTRODUCTION: Cerebral cavernous malformations (CCMs) are rare developmental cerebrovascular malformations. The risk of epilepsy is high in patients with CCMs, but the incidence of epilepsy has not been reported in a pure pediatric population. We herein present 14 pediatric cases of CCMs, including five with CCM-related epilepsy, and examine the incidence of CCM-related epilepsy in this pediatric population.  Methods: Pediatric patients with CCMs who visited our Hospital between November 1, 2001, to September 31, 2020, were retrospectively screened for inclusion, and 14 were enrolled.  Results: Fourteen enrolled patients were divided into two groups based on the presence or absence of CCM-related epilepsy. The "CCM-related epilepsy group" (n = 5) consisted of five males with a median age of 4.2 (range: 0.3-8.5) years at the first visit. The "non-epilepsy group" (n = 9) consisted of seven males and two females with a median age of 3.5 (range: 1.3-11.5) years at the first visit. The prevalence of CCM-related epilepsy at the time of the present analysis was 35.7%. Follow-up periods in CCM-related epilepsy and non-epilepsy groups were 19.3 and 24.9 patient-years, respectively: the incidence was 11.3% per patient-years. The frequency of seizures due to intra-CCM hemorrhage as the primary symptom was significantly higher in the CCM-related epilepsy group than in the non-CCM-related epilepsy group (p = 0.01). Other clinical characteristics, i.e., primary symptoms including vomiting/nausea and spastic paralysis, magnetic resonance imaging findings, including the number or maximum diameter of CCMs, cortical involvement, intra-CCM hemorrhage, and infratentorial lesions, surgical resection, and non-epileptic sequelae, such as motor disability and intellectual disability, did not significantly differ between the groups.  Discussion: The incidence of CCM-related epilepsy in the present study was 11.3% per patient year, higher than in adults. This discrepancy may be attributed to these studies including both adult and pediatric patients, whereas the present study examined a pure pediatric population. The presence of seizures due to intra-CCM hemorrhage as the initial symptom was a risk factor for CCM-related epilepsy in the present study. To elucidate the pathophysiology of CCM-related epilepsy or the reason for its higher incidence in children than in adults, further analyses of a large number of children with CCM-related epilepsy are warranted.

A case of recurrent refractory cervical primary histiocytic sarcoma treated with pembrolizumab.

Histiocytic sarcoma (HS) is a rare disease with a poor prognosis. The efficacy of immune checkpoint inhibitors for this disease has not been established. A 13-year-old boy with HS refractory to conventional chemotherapy was treated with pembrolizumab, an immune checkpoint inhibitor. After treatment, the primary lesion and the bone metastases showed improvement; however, new metastatic lesions also occurred. This case suggests that the effect of immune checkpoint inhibitors might depend not only on programmed death ligand-1 expression and the ratio of tumor mutational burden, but also on other factors, such as the tumor microenvironment. Evaluation of more cases is required to identify biomarkers that define the efficacy of immune checkpoint inhibitors.

Impact Damage Detection Using Chirp Ultrasonic Guided Waves for Development of Health Monitoring System for CFRP Mobility Structures.

When impact damage occurs in carbon fiber-reinforced plastic (CFRP) structures, it is barely visible but may cause significant degradation in the mechanical properties of the structure. Hence, a structural health monitoring (SHM) system that can be installed in CFRP mobility structures and is sensitive to impact damage is needed. In this study, we attempted to establish an SHM system based on ultrasonic guided waves, which are generated by inputting a broadband chirp signal into a film-like piezoelectric actuator. The relationship between impact damage size and maximum time-of-flight (ToF) delay was investigated for three types of CFRP plates: woven, non-woven, and hybrid laminates. As a result, it was found that the maximum ToF delay increased linearly with an increase in the damage size for all CFRP laminates. Moreover, the amplitude of the A0 mode was found to be significantly affected by the damage length in the wave propagation direction. Thus, this SHM method using chirp ultrasonic waves can quantitatively evaluate the size and extent of the impact damage in CFRP laminates.

Determination of Length of Interdigitation Zone by Optical Coherence Tomography and Retinal Sensitivity by Microperimetry and Their Relationship to Progression of Retinitis Pigmentosa.

PURPOSE: To investigate the annual progression of retinitis pigmentosa (RP) by changes in retinal sensitivity and length of photoreceptor microstructures. METHOD: The medical records of patients with typical RP followed at Chiba University Hospital were reviewed. The retinal sensitivity was measured by Micro Perimeter-1, and the lengths of the intact external limiting membrane (ELM), ellipsoid zone (EZ), and interdigitation zone (IZ) were measured by spectral-domain optical coherence tomography. The baseline values and annual progression rates were determined. The significance of the correlations among these factors was determined by generalized estimating equation regression analysis. RESULTS: Forty-six eyes of 24 patients who were examined over a mean follow-up period of 3 years were studied. The annual changes in the retinal sensitivity (p = 0.0035) and the lengths of the EZ (p = 0.037) and IZ (p = 0.0033) were significantly correlated with their baseline values. The annual change in the retinal sensitivity was significantly correlated with the length of the EZ at the baseline (p = 0.020). CONCLUSIONS: The significant correlation between the annual progression of the retinal sensitivity and the baseline retinal sensitivity and lengths of the EZ and IZ in patients with RP indicate that the retinal sensitivity, the EZ, and the IZ can be useful parameters to predict the annual progression of RP.

CORRELATIONS BETWEEN CHOROIDAL STRUCTURES AND VISUAL FUNCTIONS IN EYES WITH RETINITIS PIGMENTOSA.

PURPOSE: To investigate the choroidal structures in the enhanced depth imaging optical coherence tomographic images in eyes with retinitis pigmentosa (RP) and to determine correlations between the choroidal structures and visual functions. METHODS: The enhanced depth imaging optical coherence tomographic images of 100 eyes with typical RP and 60 age-, sex-, and axial length-matched normal eyes were binarized using ImageJ. The cross-sectional luminal and stromal areas of the inner and outer subfoveal choroid of 1,500-µm width were measured. The inner choroid included the choriocapillaris and medium vessel layer, and the outer choroid included the larger vessel layer. RESULTS: In the inner choroid, the luminal area and the ratio of luminal/total choroidal area (L/C ratio) were significantly smaller in RP than in controls (P = 0.010, P < 0.001, respectively), whereas the stromal area was not significantly different (P = 0.114). The inner choroidal L/C ratio was significantly correlated with the best-corrected visual acuity, mean deviation, foveal sensitivity, width of the ellipsoid zone, and central foveal thickness in RP after adjusting for the axial length, age, and sex (all P < 0.005). CONCLUSION: The significant correlations between the inner choroidal structures and the visual functions and retinal structures indicate that the choroidal structures are altered in association with the progression of RP.

Atypical teratoid/rhabdoid tumor of the sellar region in adult women: Is it a sex-related disease?

Atypical teratoid/rhabdoid tumor (AT/RT) is a highly malignant embryonal tumor in children and a rare entity. Although adult AT/RT is extremely rare, some cases of adult-onset AT/RT in the sellar region have been described. Here, we report an adult patient with AT/RT of the sellar region in whom it was difficult to make a definitive diagnosis and the clinical course was aggressive. This is the first report of autopsy findings that could confirm the clinical characteristics of this rare unresolved pathology, and will contribute to the improvement of prognosis. In addition, a literature review was performed to clarify this exceptionally rare condition. Interestingly, all reported adult patients with sellar AT/RT, along with the present case, were female. This raises the possibility of its being a sex-related disease. However, further studies are required to come to a definitive conclusion.

Neuroendoscopy via an Extremely Narrow Foramen of Monro: A Case Report.

Herein, safe and reliable neuroendoscopic biopsy via an extremely narrow foramen of Monro (ENFM) for a non-hydrocephalic patient with hypothalamic and pineal region tumors was successfully applied. A 17-year-old boy presented with hypothalamic manifestations attributed to hypothalamic and pineal region tumors. Small ventricles were seen. Intraoperatively, to advance different diameter steerable fiberscopes via ENFM, the third ventricle was flushed to induce a moment increase in the intraventricular pressure with subsequent dilatation of FM. Postoperative course was uneventful. Histopathological studies revealed a yolk sac tumor. Adjuvant therapy was applied. Follow-up neuroimaging disclosed marvellous improvement of the condition. His symptoms gradually improved.

A Rare Case of Pediatric Lumbar Spinal Ependymoma Mimicking Meningitis.

Spontaneous acute subarachnoid hemorrhage (SAH) from lumbar ependymoma in children is rare. We report a case of a 14-year-old boy who developed sudden radicular low back pain while playing baseball. He was initially managed conservatively in a local hospital for suspected lumbar disc herniation, but he later developed meningeal symptoms and fever before being referred to our hospital. He underwent a diagnostic lumbar puncture in the emergency department; his cerebrospinal fluid suggested an SAH. Physical examination showed meningeal signs and cauda equina features. Cerebrospinal fluid analysis was negative for bacterial meningitis. Lumbar magnetic resonance imaging revealed a mass characterized as a hemorrhagic lesion. The patient had an emergent evacuation of the mass through the posterior approach. Postoperatively, his symptoms resolved completely. The histologic diagnosis was, surprisingly, an ependymoma (World Health Organization grade II). This case is particularly interesting because of its rarity in children, and its pattern of presentation. Although bacterial or viral meningitis is the most frequent cause of meningeal features in children, SAH from a hemorrhagic spinal tumor should be considered. Ultimately, a high index of suspicion is needed for prompt diagnosis.

Evaluation of Metallic Artifacts Caused by Nonpenetrating Titanium Clips in Postoperative Neuroimaging.

BACKGROUND: Nonpenetrating titanium clips create no suture holes and thereby reduce cerebrospinal fluid leakage after dural closure. However, no data exist regarding metallic artifacts caused by these clips during postoperative neuroimaging. We aimed to evaluate clip-related artifacts on postoperative magnetic resonance (MR) images of 17 patients who underwent spinal surgery. METHODS: A phantom study evaluated the size of metallic artifacts, and a clinical study evaluated the quality of postoperative spinal MR images. Both 1.5-T studies used T1-weighted and T2-weighted fast spin echo sequences. The phantom study compared clip and artifact size for 10 clips. Artifacts were defined as signal voids surrounded by high signal amplitude that followed the clip shape. In the clinical study, 2 neurosurgeons assessed 22 images from 17 patients of the spinal cord, cauda equina, and paravertebral muscles adjacent to the nonpenetrating titanium clips, using 5-point scales. RESULTS: Mean metallic artifact sizes were 4.82 ± 0.16 mm (T1) and 4.66 ± 0.25 mm (T2; P < 0.001 vs. control). The former and latter were respectively 207% and 200% larger than the clip size. Both readers graded spinal cord and paravertebral muscles images as 3 or 4, indicating very good image quality regardless of clip-related artifacts, with excellent interobserver agreement (κ = 0.99 and 0.98, respectively). CONCLUSIONS: Metallic artifacts caused by nonpenetrating titanium clips were 200% larger than the actual clip but did not affect spinal cord and extradural tissue visualization. The use of these clips for closing the spinal dura mater does not alter postoperative radiologic evaluation quality.

Giant cavernous malformation in the ventrolateral midbrain with extension into the thalamus: a case report of a paramedian supracerebellar transtentorial approach.

Cavernous malformations (CMs) of the midbrain and thalamus are relatively rare and particularly difficult to be resected given their location in eloquent tissues. Here, we report a case of a 14-year-old boy who experienced repeated and progressive right hemiparesis. Image examinations showed a gradually enlarged CM originated in the left ventrolateral midbrain extending to the left thalamus with repeated hemorrhage. By performing a paramedian supracerebellar transtentorial approach, the CM was totally removed, and the patient recovered without any new neurological deficit. The authors' experience suggests that this approach is eminent in treating giant lesions involving the ventrolateral midbrain and thalamus.

Two Cases of Masticator Space Abscess Spreading from Infections of the Mandibular Teeth.

The masticator space is located between the masseteric fascia and the pterygoid muscle fascia. Here we report two cases of masticator space abscesses spreading from infections of mandibular teeth. Case 1 is an 85-year-old lady who were referred to Yokohama City University Hospital with a left-cheek swelling and trismus. An enhanced CT scan revealed an abscess extending from the left infratemporal fossa to the temporal fossa. A purulent discharge was observed from her left lower gingiva. We performed surgical drainage under general anesthesia. After infection control, the affected teeth were extracted. Case 2 is an 82-year-old lady who was administered oral bisphosphonate for osteoporosis. She presented to another hospital with fever, trismus and swelling anterior to the right ear after right lower tooth extraction. Because MRI revealed persistent osteomyelitis of her mandible even after antibiotic treatment, she was referred to us. Enhanced CT showed an abscess in the right infratemporal fossa. After surgical drainage similar to Case 1, antibiotics were administered for approximately 4 months to control the osteomyelitis.　 It is important to recognize that infections of the mandibular teeth can cause an abscess in the masticator space through the pterygomandibular and infratemporal spaces.

Online estimation of a cognitive performance using heart rate variability.

This paper presents online estimation framework of a cognitive performance using heart rate variability (HRV). Although our former framework could estimate relative changes in one user's cognitive performance after it had finished measuring his/her HRV, it was unable to estimate a cognitive performance repeatedly or to compare the estimated results obtained for multiple users. To address these problems, we have developed a framework for online estimation of a cognitive performance. Experimental results show our framework estimates a cognitive performance more accurately than the previous study did using multiple vital sensors. It can also estimate a user's cognitive performance by comparing it with those estimated for others. It therefore has the potential to help managerial personnel monitor their workers' performances in real time to suggest rest periods or changes in work duties.

[A case of ophthalmic artery occlusion following injection of hyaluronic acid into the glabellar area].

PURPOSE: We report a case of unilateral blindness due to ophthalmic artery occlusion following injection of hyaluronic acid into the glabellar area for facial soft-tissue augmentation. CASE: A 20-year old woman underwent injection of hyaluronic acid into the glabellar area at an aesthetic plastic clinic. Immediately after injection, she suffered nausea, pain, paralysis of limbs and visual loss in her right eye. Hyaluronidase was instanly injected into the same place, but these symptoms did not improve. She was transferred to our hospital's emergency department. At the first examination, she had no light perception in the right eye and her right pupil was dilated. The fundus examination revealed right central artery occlusion. No significant findings were detected in her head. Eye ball massage, hyperbaric oxygen therapy, and drip infusion of urokinase were conducted, but no improvement resulted. Fluorescein and indocyanine green angiography showed no filling of the right retinal and choroidal arteries. Electroretinogram was completely disappeared. Magnetic resonance angiography could not reveal the obstruction point of the ophthalmic artery. CONCLUSION: Ophthalmic artery occlusion was believed to have occured after injection of hyaluronic acid into the glabellar area.