Stenting for Innominate Artery Stenosis Under Double-Filter Protection of the Anterior and Posterior Circulation via the Right Brachial Artery.

Several protocols for angioplasty and stenting for stenosis of an innominate artery (IA) are reported, but the protocols are sometimes complicated and have disadvantages. We report a case of IA stenosis presenting ischemic symptoms in a 58-year-old woman. Stenting for the IA stenosis was performed through the right femoral artery. The cerebral protection was placed via the right brachial artery, with a filter at the right internal carotid artery and another filter at the right vertebral artery. The symptomatic IA stenosis was resolved without any complications. Regardless of the direction of blood flow, simultaneous protection of both the anterior and posterior cerebral circulation is necessary during IA stenting. Double-filter protection can provide excellent cerebral protection during an IA stenting procedure.

[Treatment of a Traumatic Direct Carotid Cavernous Fistula with an Intradural Internal Carotid Artery Pseudoaneurysm Using a Low-profile Visualized Intraluminal Support(LVIS)Stent:A Case Report].

Traumatic carotid cavernous fistula(CCF)is known to present a direct connection between the cavernous segment of the internal carotid artery(ICA)and the cavernous sinus(CS). In rare cases, the fistula is formed between the intradural internal carotid artery(ICA)and the cavernous sinus(CS)via a pseudoaneurysm(pAN), requiring appropriate management and aggressive surgical treatment. We describe a 58-year-old man who sustained a severe head injury diagnosed as traumatic CCF treated with an intradural pAN procedure and transarterial coil embolization combined with a Low-profile Visualized Intraluminal Support(LVIS)stent. While slow arteriovenous shunt flow persisted at the end of the surgery, the fistula was completely occluded on the digital subtraction angiography obtained 2 weeks after the procedure. It was suspected that the flow-diversion effect of the LVIS stent might have caused the curable progression of the fistula occlusion.

Frequency and Predicting Factors on Chronic Expanding Intracerebral Hematoma in Spontaneous Intracerebral Hemorrhage.

BACKGROUND: Chronic expanding intracerebral hematoma is a well-known complication of spontaneous intracerebral hemorrhage. However, because chronic expanding intracerebral hematoma is relatively rare, it has not been studied systemically. The purpose of this study was to characterize a patient population with chronic expanding intracerebral hematoma, and to identify the predictive factors for it. METHODS: We retrospectively evaluated 112 patients with spontaneous putaminal hemorrhage who were treated at our institution between January 1, 2010 and December 31, 2015. Data on age, sex, Glasgow Coma Scale score, presence of intraventricular hemorrhage, and intracerebral hemorrhage volume were collected, and their predictive values for chronic expanding intracerebral hematoma were investigated. We also evaluated the predictive value of a characteristic radiological finding at onset called the "layer sign," which was represented as a fluid level adjacent to the clot. RESULTS: Chronic expanding intracerebral hematoma was observed in 4 patients (4.9%) with spontaneous intracerebral hemorrhage. Only the layer sign was significantly related to chronic expanding intracerebral hematoma (P = .003), and was found to be independently associated with chronic expanding intracerebral hematoma in a multivariate analysis (odds ratio, 18.6; 95% confidence interval, 1.19-291.0; P = .037). CONCLUSIONS: The frequency of chronic expanding intracerebral hematoma in those with spontaneous intracerebral hemorrhage was estimated at 4.9%. The layer sign was a useful factor for predicting chronic expanding intracerebral hematoma.

[Apixaban-Related Convexal Subarachnoid Hemorrhage:A Case Report].

The risk of anticoagulant-associated intracranial hemorrhage(ICH)is relatively low in patients treated with non-vitamin K antagonist oral anticoagulants(NOAC). The anticoagulant-associated ICH comprises mainly intraparenchimal hemorrhage. Subdural hematoma and subarachnoid hemorrhage(SAH)are rare complications after treatment with NOAC, trauma being the most common cause for these two types of ICH. We report a case of non-traumatic convexal SAH(cSAH)associated with Apixavan. A 68-year-old man with repeated history of cerebral embolism with cardiogenic cause presented with weakness of the lower limbs. Magnetic resonance imaging revealed infarctions, and treatment with apixaban(5 mg twice per day)was administered. Three days later, SAH in the right superior frontal sulcus was discovered incidentally on computed tomography(CT). NOAC-associated SAH is a rare manifestation. Cerebral amyloid angiopathy(CAA)is the most common cause of cSAH in the elderly, and cSAH is supposed to be a warning sign of cerebral hemorrhage in CAA. Patients with CAA started on NOAC require careful monitoring.

[A case of solitary fibrous tumor in the sella turcica].

A 64-year-old male presented with an incidental tumor in the sella turcica during a brain medical checkup. Because he lacked any neurological symptoms or signs of pituitary dysfunction, the patient did not undergo surgery. Three years later, visual disturbances developed, including poor eyesight and visual field defects. The response to the growth hormone(GH)releasing peptide-2 demonstrated severe GH deficiency. MRI revealed an enlarged tumor appearing as a mosaic pattern of high and very low intensity on T2-weighted imaging. The region of very low intensity on T2-weighted imaging exhibited enhancement after T1 gadolinium-DTPA administration. The tumor was totally removed via the microscopic trans-sphenoidal approach in combination with endoscopic observation. The hard tumor adhered to the dura of the sella turcica and the medial wall of the left cavernous sinus. Histological verification confirmed a solitary fibrous tumor(SFT). Fourteen months after the operation, MRI revealed no recurrent tumors. SFT infrequently occurs in the sella turcica; however it should be included in the differential diagnosis in cases of enhanced tumors with marked low intensity on T2-weighted imaging.

Impact of intravenously administered cranial bone-derived mesenchymal stem cells on functional recovery in experimental spinal cord injury.

Impairments of the central nervous system, such as stroke, brain trauma, and spinal cord injury (SCI), cannot be reversed using current treatment options. Herein, we compared the characteristics of rat cranial bone-derived mesenchymal stem cells (rcMSCs) and rat bone marrow-derived mesenchymal stem cells (rbMSCs). We also investigated the therapeutic effects of intravenously administered rcMSCs and rbMSCs in a rat model of cervical SCI (cSCI) and elucidated its undrelying mechanism. Comprehensive comparative bioinformatics analysis of rcMSCs and rbMSCs RNA sequencing revealed that genes associated with leukocyte transendothelial migration and chemokine signaling were significantly downregulated in rcMSCs. Rats were divided into three groups that received intrtravenous administration of rcMSC, rbMSC, or phosphate-buffered saline (control) 24 h after cSCI. The rcMSC-treated group showed improved functional recovery over the rbMSC-treated and control groups, and reduced lesion volume compared with the control group. The mRNA expression of nitric oxide synthase 2 at the spinal cord lesion site was significantly higher in the rcMSC-treated group than in the control and rbMSCs-treated groups, whereas that of transforming growth factor-ß was significantly higher in the rcMSC-treated group compared to that in the control group. The transcriptome data indicated that rcMSCs and rbMSCs differentially affect inflammation. The intravenous administration of rcMSCs contributed to functional recovery and lesion reduction in cSCI. The rcMSCs have the potential to induce an anti-inflammatory environment in cSCI.

A novel rat model for longitudinal electrophysiological evaluation after cold-induced brain injury.

OBJECTIVE: Cerebral contusion models of cold-induced injury are widely used in animal studies. However, owing to the difficulty of longitudinal recording of electrical stimulation transcranial motor evoked potential (tcMEP) in brain injury models of incomplete paralysis, to the authors' knowledge there have been no multimodal evaluations of cold-induced brain injury models that have included motor function and electrophysiological and histological evaluations. Therefore, in this study the authors aimed to perform a multimodal evaluation of a rat model of brain injury. METHODS: A brain injury model in female rats and a tcMEP recording technique based on the authors' previous study were established to enable multifaceted analysis, including longitudinal electrophysiological evaluation. RESULTS: The model showed incomplete paralysis of the right forelimb. Motor function showed recovery over time, and histological evaluation showed tissue changes associated with cerebral contusion. In addition, stable tcMEP waveforms were recorded before and after surgery and up to 4 weeks after injury. The tcMEP amplitude decreased significantly after injury and recovered over time. Furthermore, the amplitudes at 1, 7, and 14 days after injury were significantly lower than those at preinjury (p < 0.0006, p < 0.0007, and p < 0.0067, respectively). CONCLUSIONS: In the present study, the authors established a novel cold-induced brain injury rat model and technique that allowed for the evaluation of longitudinal tcMEP recording and demonstrated that multimodal evaluation for brain injury can be performed. This model can potentially be applied in future investigations of various therapies for brain injury.

Assessment of Intraoperative Spinal Angiography via the Popliteal Artery for Spinal Vascular Diseases.

OBJECTIVE: Intraoperative spinal angiography via the popliteal artery for patients in the prone position has been reported only twice in 4 patients. This study aimed to clarify the safety precautions to be taken with this technique in a larger patient cohort. METHODS: Seven patients with spinal vascular disorders underwent intraoperative spinal angiography in the prone position via the popliteal artery. Ultrasound was used to evaluate the neurovascular anatomy in the popliteal fossa and guide the arterial puncture. Patient characteristics, features of angiography devices, puncture attempts, and angiography-related complications, such as hematoma formation and injury to the neurovascular bundle, were analyzed. RESULTS: The average number of arterial puncture attempts was 1.3 times (range: 1-2). Sheaths (4 and 4.5 Fr) with different ineffective lengths were used. In 1 case, a 4.5-Fr sheath was replaced with a 4-Fr sheath with a shorter noneffective length as the length of the catheter limited access to the target. Catheters with Type-JB2 tip shapes were used for craniocervical junction lesions, and those with Type-KAGAWA tip shapes were used for thoracic and lumbar spinal lesions. No puncture site complications were observed in any patient. CONCLUSIONS: Intraoperative spinal angiography via the popliteal artery was an effective tool in surgeries for spinal vascular diseases. The introduction of the ultrasound enabled atraumatic puncture of the popliteal artery. Spinal targets above T5 to T6 may be inaccessible from the popliteal fossa when using a 100-cm-long catheter.

Distinctive MicroRNA Profiles in Serum of Patients with Neurofibromatosis Type 2: A Bioinformatic Exploratory Study.

OBJECTIVE: The objective of this study was to explore serum microRNA (miRNA) profile characteristic of patients with neurofibromatosis type 2 (NF2), including both sporadic and familial cases, by comprehensive analysis of miRNA expression using next-generation sequencing. METHODS: Nine patients with NF2 were included in this study. In addition, 7 patients with unilateral acoustic neuroma without a family history of NF2 were invited to participate as the control cohort in the study. Total RNA including the small RNAs was extracted from serum. We comprehensively analyzed the expression of miRNAs using next-generation sequencing, and differentially expressed miRNAs (DEMs) were analyzed. Biological implications of DEMs were analyzed by Gene Ontology/Kyoto Encyclopedia of Genes and Genomes analysis. RESULTS: Distinctive miRNA profiles (16 miRNAs were significantly downregulated, and 4 miRNAs were significantly upregulated) were observed in the comparison between all patients with NF2 and controls. In the NF2 subgroup analysis, 23 miRNAs (including hsa-miR-let7b, hsa-miR-let7c, and hsa-miR-200a) and 7 miRNAs (including hsa-miR-193b) were identified as specifically downregulated miRNAs in sporadic NF2 and familial NF2, respectively. Moreover, hsa-miR-193a and hsa-miR-504 were identified as specifically upregulated miRNAs in sporadic NF2 and familial NF2, respectively. Gene Ontology/Kyoto Encyclopedia of Genes and Genomes analysis showed that identified DEMs were mainly enriched in gene silencing by miRNA, miRNAs in cancer, and regulation of angiogenesis. CONCLUSIONS: We were able to identify distinctive miRNA profiles in the serum of patients with NF2, including both sporadic and familial cases, by comprehensive miRNA expression analysis using miRNA sequencing.

Healing process of Type II odontoid fractures after C1-C2 posterior screw fixation: Predictive factors for pseudoarthrosis.

Background: The healing process after C1-C2 posterior screw fixation (C1-C2 PSF) for odontoid fractures is not well understood. Here, we evaluated such processes and identified factors potentially contributing to pseudoarthroses following fusions for Type II odontoid fractures. Methods: Pre- and post-operative cervical radiographs and computed tomography (CT) images from 15 patients with preoperative Type II odontoid fractures who underwent C1-C2 PSF were retrospectively reviewed. Results: CT images identified three areas of bone fusion: The primary fracture site in the dens (9/15 patients, 60%), the atlanto-dental interspace (ADI) (10/15, 67%), and C1-C2 interlaminar space after onlay bone grafting (4/15, 27%). All patients showed bone fusion in at least one of three areas, while only one patient (6.7%) achieved bone fusion in all three areas. With these overall criteria, nine of 15 patients (60%) were considered fused, while six patients (40%) were determined to exhibit pseudoarthroses. Univariate analyzes showed that the preoperative C2-C7 SVA for the nonunion group was significantly larger versus the union group, and bone fusion at the level of the ADI was significantly more common in the nonunion versus the union group. Conclusion: CT studies identified three anatomical areas where bone fusion likely occurs after C1-C2 PSF. Increased sagittal balance in the cervical spine may negatively impact the fusion of odontoid fractures. Further, bone fusion occurring at other sites, not the primary fracture location, through stress shielding may contribute to delayed or failed fusions.

Longitudinal electrophysiological changes after mesenchymal stem cell transplantation in a spinal cord injury rat model.

Transcranial electrically stimulated motor-evoked potentials (tcMEPs) are widely used to evaluate motor function in humans and animals. However, the relationship between tcMEPs and the recovery of paralysis remains unclear. We previously reported that transplantation of mesenchymal stem cells to a spinal cord injury (SCI) rat model resulted in various degrees of recovery from paraplegia. As a continuation of this work, in the present study, we aimed to establish the longitudinal electrophysiological changes in this SCI rat model after mesenchymal stem cell transplantation. SCI rats were established using the weight-drop method. The model rats were transvenously transplanted with two types of mesenchymal stem cells (MSCs), one derived from rat cranial bones and the other from the bone marrow of the femur and tibia bone, 24 h after SCI. A phosphate-buffered saline (PBS) group that received only PBS was also created for comparison. The degree of paralysis was evaluated over 28 days using the Basso-Beattie-Bresnahan (BBB) scale and inclined plane task score. Extended tcMEPs were recorded using a previously reported bone-thinning technique, and the longitudinal electrophysiological changes in tcMEPs were investigated. In addition, the relationship between the time course of recovery from paralysis and reappearance of tcMEPs was revealed. The appearance of the tcMEP waveform was earlier in MSC-transplanted rats than in PBS-administered rats (earliest date was 7 days after SCI). The MEP waveforms also appeared at approximately the same level on the BBB scale (average score, 11 points). Ultimately, this study can help enhance our understanding of the relationship between neural regeneration and tcMEP recording. Further application of tcMEP in regenerative medicine research is expected.

Establishment of longitudinal transcranial stimulation motor evoked potentials monitoring of the forelimbs and hindlimbs in an ischemic stroke rat model.

Evaluation of motor function ischemic stroke rat models includes qualitative assessments such as the modified neurological severity score (mNSS). However, mNSS cannot evaluate the function of forelimbs and hindlimbs separately. We quantitatively assessed motor function in a middle cerebral artery occlusion (MCAO) rat model of ischemic stroke. We recorded transcranial stimulation motor evoked potentials (tcMEPs) from MCAO rats and measured the changes in onset latency and amplitude at the forelimbs and hindlimbs up to 28 days after stroke. All MCAO subjects showed hemiparesis. The amplitudes of tcMEPs in both fore- and hindlimbs were inversely correlated with mNSS scores, but the amplitudes in the forelimbs improved later than those in the hindlimbs. The onset latency of tcMEPs in the forelimbs and hindlimbs remained almost unchanged during the follow-up period. Our results showed the differences in tcMEPs amplitude recovery times between the forelimbs and hindlimbs after MCAO, which emphasizes the importance of separately evaluating forelimbs and hindlimbs in post-ischemic stroke models. This minimally invasive and longitudinal quantitative method could be useful for further research on diseases and neurogenesis.

Imaging evolution from "presyrinx" to syrinx in patient with spinal lipoma.

Background: The evolution of syrinx formation has rarely been documented. Here, we report a patient whose "presyrinx" evolved on successive magnetic resonance (MR) images to a mature syrinx. Case Description: A patient had a lipoma and tethered cord at birth. At 3 weeks of age, he had undergone a partial removal of the lipoma and untethering of the spinal cord. At age 6, the thoracic MR images showed edema within the gray matter of the cord at the T7 level, consistent with a "presyrinx." In addition, subsequent MR studies (i.e., at age 7) showed a small cavity in the right posterior horn of the cord accompanied by further expansion throughout the right-sided gray matter. Despite repeated cord untethering at age 7, the T7 parenchymal cord change evolved into a mature syrinx by age 10. Conclusion: An infant with a lipoma/tethered cord, despite two instances of cord detethering (i.e., ages 3 weeks and 7 years), showed continued MR evolution of a "presyrinx" to a mature syrinx by age 10.

Spinal arteriovenous fistula in the lipoma of the filum terminale: A report of two cases and literature review.

BACKGROUND: Filum terminale arteriovenous fistulas (FTAVFs) are rare and their pathogenesis remains unknown. The authors report two cases of FTAVF that arose in the lipoma of the filum terminale. CASE DESCRIPTION: The two patients were 72 and 76 years of age, and both presented with a progressive paraparesis. The first patient had an arteriovenous fistula (AVF) located at L5 that was supplied by the anterior spinal artery originating from the left T10 intercostal artery. The second patient's AVF at L3-4 was fed by the anterior spinal artery originating from the left T8 intercostal artery. Both patients underwent partial resection of the filum terminale at the location of the shunts. The pathological examinations revealed that both the AVFs were embedded in the adipose tissue of the filum terminale, revealing the fatty fila that were not visible in preoperative magnetic resonance images. CONCLUSION: Two cases of FTAVF were successfully treated by obliterating the fistulas through partial resection of the affected fatty filum terminale. The literature review revealed 13 cases of FTAVF concomitant with the lipomas of the filum terminale. Resection and histological evaluation of the filum terminale should be performed to treat and elucidate the pathogenesis of FTAVF.

Spinal Osseous Epidural Arteriovenous Fistula with Intradural Reflux: A Case Report.

The authors report a rare case of spinal osseous epidural arteriovenous fistula (AVF) with intradural reflux. A 71-year-old lady with a past history of a T12 compression fracture and neurofibromatosis type 1 presented with progressive paraparesis. Magnetic resonance (MR) images of the thoracolumbar spine showed edema of the spinal cord and flow voids. Catheter angiography revealed segmental arteries from T11 to L1 feeding an AVF in the epidural space. The AVF drained not only into the epidural venous plexus but also into the perimedullary veins. Of note, there was an intraosseous drainage route that involved the basivertebral vein of T12. Under the diagnosis of spinal osseous epidural AVF with intradural reflux, surgical interruption of the intradural arterialized draining vein was performed. Spinal osseous epidural AVF with intradural reflux is rare with only four cases reported in the past. We believe that spinal osseous epidural AVF should be recognized as a variant of spinal epidural AVF.

Effects of Preservation of the Semispinalis Cervicis Inserted into C2 on Craniocervical Alignment After Laminoplasty.

OBJECTIVE: The preservation of nuchal musculature is essential for preventing axial pain and cervical malalignment after laminoplasty. A few studies have examined the effect of preservation of nuchal musculature on the degenerative progression after laminoplasty. We aimed to clarify the influence of preservation of the semispinalis cervicis inserted into C2 on cervical degenerative change and alignment after laminoplasty. METHODS: We retrospectively reviewed 106 consecutive patients who underwent C3-7 laminoplasty for cervical spondylotic myelopathy during 2006-2017. Patients were classified into 2 groups according to the preservation (P-group; n = 33) or detachment (D-group; n = 73) of the Semispinalis cervicis muscles inserted into the C2 spinous process. Parameters of cervical sagittal alignment, range of motion, and progressive degenerative changes next to or within the range of laminoplasty were evaluated in cervical spine radiographs, and magnetic resonance images obtained during follow-up period. RESULTS: In the D-group, the postoperative C2-7 Cobb angle significantly decreased (-0.06°/month), while the O-C2 Cobb angle significantly increased (0.07°/month). In addition, the C2-7 range of motion significantly decreased in the D-group (-0.12°/month). Degenerative changes in the laminoplasty range were found in 5 patients per group. Three patients from the D-group developed retroodontoid pseudotumors (P < 0.001). CONCLUSIONS: To maintain horizontal gaze, the craniocervical segment can compensate for the loss of lordosis by increasing the Cobb angle. Excessive compensation may exert mechanical stress on the atlantoaxial junction, contributing to the development of a retroodontoid pseudotumor. Preservation of the semispinalis cervicis inserted into C2 is critical for the prevention of malalignment after laminoplasty.

Transplantation of rat cranial bone-derived mesenchymal stem cells promotes functional recovery in rats with spinal cord injury.

Cell-based therapy using mesenchymal stem cells (MSCs) is a novel treatment strategy for spinal cord injury (SCI). MSCs can be isolated from various tissues, and their characteristics vary based on the source. However, reports demonstrating the effect of transplanted rat cranial bone-derived MSCs (rcMSCs) on rat SCI models are lacking. In this study, we determined the effect of transplanting rcMSCs in rat SCI models. MSCs were established from collected bone marrow and cranial bones. SCI rats were established using the weight-drop method and transplanted intravenously with MSCs at 24 h post SCI. The recovery of motor function and hindlimb electrophysiology was evaluated 4 weeks post transplantation. Electrophysiological recovery was evaluated by recording the transcranial electrical stimulation motor-evoked potentials. Tissue repair after SCI was assessed by calculating the cavity ratio. The expression of genes involved in the inflammatory response and cell death in the spinal cord tissue was assessed by real-time polymerase chain reaction. The transplantation of rcMSCs improved motor function and electrophysiology recovery, and reduced cavity ratio. The expression of proinflammatory cytokines was suppressed in the spinal cord tissues of the rats that received rcMSCs. These results demonstrate the efficacy of rcMSCs as cell-based therapy for SCI.

Differences and characteristics of symptoms by tumor location, size, and degree of spinal cord compression: a retrospective study on 53 surgically treated, symptomatic spinal meningiomas.

OBJECTIVE: The differences in symptoms of spinal meningiomas have rarely been discussed from the perspective of tumor characteristics. The main purpose of this paper was to define the differences, if any, in symptoms in patients with spinal meningiomas with respect to tumor size, location, and degree of spinal cord compression. The authors also sought the threshold of spinal cord compression that causes motor weakness. METHODS: The authors conducted a retrospective study of 53 cases of spinal meningiomas that were surgically treated from 2013 to 2018. Symptoms related to the tumor were classified as motor weakness, sensory disturbance, pain, and bowel/bladder dysfunction. Based on MR images, tumor location was classified by spinal level and by its attachment to the dura mater. Tumor dimensions were also measured. Occupation ratios of the tumors to the spinal canal and degree of spinal cord flattening were sought from the axial MR images that showed the highest degree of spinal cord compression. RESULTS: Motor weakness and sensory disturbance were significantly more common in thoracic spine meningiomas than in cervical spine meningiomas (p < 0.001 and p = 0.013, respectively), while pain was more common in meningiomas at the craniovertebral junction (p < 0.001). The attachment, height, width, depth, and volume of the tumor showed no significant difference irrespective of the presence or absence of each symptom. In cases of motor weakness and sensory disturbance, occupation ratios and spinal cord flattening ratios were significantly larger. However, these ratios were significantly smaller in the presence of pain. Multivariate logistic regression analysis revealed that occupation ratio independently contributed to motor weakness (OR 1.14, p = 0.035) and pain (OR 0.925, p = 0.034). Receiver operating characteristic curve analysis suggested that occupation ratio with a value of 63.678% is the threshold for the tumor to cause motor weakness. CONCLUSIONS: The study showed the difference in clinical presentation of spinal meningiomas by spinal level, occupation ratio, and spinal cord flattening ratio. An occupation ratio of approximately 64% could be utilized as the threshold value of tumor growth to cause motor weakness. Tumor growth in the cervical spine might cause pain symptoms before causing motor weakness. The relationship between the tumor and its symptomatology should be discussed with respect to tumor size relative to the surrounding spinal canal.

Asymptomatic spinal dural arteriovenous fistula: case series and systematic review.

OBJECTIVE: Spinal dural arteriovenous fistulas (SDAVFs) commonly present with symptoms of myelopathy due to venous congestion in the spinal cord; asymptomatic SDAVFs are rarely encountered. To elucidate the clinical characteristics of asymptomatic SDAVFs, the authors present 5 new cases of asymptomatic SDAVF and report the results of their systematical review of the associated literature. METHODS: Five databases were systematically searched for all relevant English-language articles on SDAVFs published from 1990 to 2018. The clinical features and imaging findings of asymptomatic SDAVFs were collected and compared with those of symptomatic SDAVFs. RESULTS: Twenty cases, including the 5 cases from the authors' experience, were found. Asymptomatic SDAVFs were more prevalent in the cervical region (35.0%); cervical lesions account for only 2% of all symptomatic SDAVFs. The affected perimedullary veins tended to drain more cranially (50.0%) than caudally (10.0%). Four cases of asymptomatic SDAVF became symptomatic, 1 case spontaneously disappeared, and the remaining 15 cases were unchanged or surgically treated. CONCLUSIONS: The higher prevalence of asymptomatic SDAVFs in the cervical spine might be a distinct feature of asymptomatic SDAVFs. Given that venous congestion is the pathophysiology of a symptomatic SDAVF, abundant collateral venous pathways and unique flow dynamics of the CSF in the cervical spine might prevent asymptomatic cervical SDAVFs from becoming symptomatic. In cases in which venous congestion is avoidable, not all asymptomatic SDAVFs will become symptomatic.

Importance of frailty evaluation in the prediction of the prognosis of patients with chronic subdural hematoma.

AIM: The present study aimed to clarify the relationship between frailty and prognosis of patients with chronic subdural hematoma. METHODS: This retrospective study involved 211 patients aged ≥65 years with chronic subdural hematoma, who underwent surgery at Higashihiroshima Medical Center, Hiroshima, Japan, between July 2011 and May 2017. The study outcome was the patient's modified Rankin Scale score at 3 months after surgery. A logistic regression analysis was carried out to analyze factors that influenced the outcome. RESULTS: Chronic subdural hematoma patients with frailty had a poorer prognosis than those without (median modified Rankin Scale: 4 and 2, P < 0.001; proportions of patients discharged to home: 35% and 91%, P < 0.001, respectively). After adjusting for patients' background, the patients' modified Rankin Scale scores at 3 months after surgery were found to be associated with age, controlling nutritional status score and recurrence, but not with frailty. However, receiver operating characteristic curves of the model with the Clinical Frailty Scale were more accurately correlated with prognosis than those of the model without this scale (area under the curve 0.98, 95% confidence interval 0.96-0.99; and 0.87, 95% confidence interval 0.82-0.91, respectively.) CONCLUSIONS: Chronic subdural hematoma patients with frailty had poorer prognosis than those without. The evaluation of the presence of frailty on admission can be an important factor in the prediction of the prognosis of chronic subdural hematoma patients. Geriatr Gerontol Int 2018; 18: 1173-1176.