The Effect of Japanese Herbal Medicines (Kampo) Goreisan and Saireito on the Prevention of Recurrent Chronic Subdural Hematoma: A Prospective Randomized Study.

BACKGROUND AND OBJECTIVES: Chronic subdural hematoma (CSDH) sometimes recurs after surgical treatment and requires reoperation. In Japan, Japanese herbal medicines (Kampo), such as Goreisan and Saireito, have been used as adjunctive therapies to prevent the recurrence of CSDH. However, no prospective randomized study has proven the efficacy of Kampo medicine in all patients. To investigate whether Goreisan and Saireito reduce the postoperative recurrence of CSDH in a prospective randomized study. METHODS: Between April 2017 and July 2019, a total of 118 patients who underwent initial burr hole surgery for CSDH were randomly assigned to the following 3 groups: (1) Goreisan for 3 months (Group G), (2) Saireito for 3 months (Group S), and (3) no medication (Group N). The primary end point was symptomatic recurrence within 3 months postoperatively, and the secondary end point was complications associated with the administration of Kampo medicine. RESULTS: Among 118 patients, 114 (Group N, n = 39; Group G, n = 37; and Group S, n = 38) were included in our analysis. In this study, byakujutsu (containing Atractylodes rhizome ) Goreisan and Saireito were used, unlike other prospective randomized studies in which sojutsu (containing Atractylodes lancea rhizome) Goreisan was used. The overall recurrence rate was 11.4% (13/114: 10 for Group N, 2 for Group G, and 1 for Group S). The recurrence rate of Group G was significantly lower than that of Group N (5.4% vs 25.6%; P = .043). The recurrence rate of Group S was also significantly lower than that of Group N (2.6% vs 25.6%; P = .02). No patients developed complications associated with the administration of Kampo medicine. CONCLUSION: This is the first study to show that Kampo medicine reduced the recurrence rate of CSDH in an overall population. This study demonstrated that byakujutsu Goreisan and Saireito may have favorable effects, unlike other studies, because byakujutsu has stronger anti-inflammatory activity than sojutsu.

Cervical radiculopathy due to extracranial vertebral artery dissection treated by stent placement with a flow diversion effect: illustrative case.

BACKGROUND: Cervical radiculopathy due to extracranial vertebral artery dissection (VAD) is extremely rare. The disease is usually treated with conservative treatment because of its favorable prognosis. However, there is a possibility that conservative treatment may bring about no improvement in radiculopathy. Although stent placement with a flow diversion effect may be effective in such cases, there are no reported cases that were treated with stent placement. OBSERVATIONS: A 40-year-old healthy man presented with severe right neck pain, right arm pain, and right arm weakness after cracking his neck. A neurological examination revealed right C5 radiculopathy. Neuroimaging studies revealed right extracranial VAD. The VAD compressed the right C5 nerve root. Although medications were administered, there was no improvement in the symptoms. He experienced severe radicular pain. The authors performed stent placement with a flow diversion effect 10 days after the onset of VAD. His radicular pain improved immediately after the procedure, and the remaining radiculopathy completely improved within 1 month. Follow-up angiography showed complete improvement of the VAD. LESSONS: Stent placement with a flow diversion effect may be considered when radiculopathy that hinders a patient's daily life exists. Stent placement may bring about rapid improvement in radiculopathy, especially radicular pain.

[Investigation of Changing Imaging Contrast Using Compressed Sensing in Gd-EOB-DTPA Hepatocyte Phase].

In recent years, gadolinium ethoxybenzyl diethylenetriamine pantaacetic acid (Gd-EOB-DTPA) has been commonly used in magnetic resonance imaging (MRI) for liver contrast studies. The purpose of this study was to investigate the effect of Hyper SENSE factor on contrast in the Gd-EOB-DTPA hepatocyte phase. The subjects were 21 patients [16 males and 5 females, aged 50-94 years (mean age 68±12years)] who underwent hepatic contrast-enhanced MRI with Gd-EOB-DTPA from March 2021 to December 2021. The contrast ratios (CRs) of liver/spleen and liver/tumor were measured when the Hyper SENSE factor was changed to 1.0, 1.4 and 1.8. As a result, there was no statistically significant difference in signal intensity and CR with the change in the Hyper SENSE factor. In this study, the acquisition time can be shortened without decreasing the CR; therefore, it was suggested to improve MR images to avoid motion artifact.

A case of posterior cerebral artery occlusion that developed into an artery of Percheron infarction.

The thalamus is predominantly supplied by multiple small vessels originating from the posterior communicating artery and the P1 and P2 segments of the posterior cerebral artery (PCA). The artery of Percheron (AOP) is a rare anatomical variant of arterial supply to the thalamus. This single thalamic perforating branch supplies the bilateral thalamus so that occlusion results in a characteristic cerebral infarction. Herein, we report a case of posterior cerebral artery occlusion that developed into an AOP infarction. A 74-year-old man, who had undergone coronary artery bypass grafting 5 days previously presented with sudden consciousness disorder and tetraplegia, and was admitted to our hospital. Magnetic resonance imaging (MRI) revealed a hyper-intense area in the bilateral paramedian thalamus on diffusion-weighted imaging and a deficit of the left PCA on MR angiography (MRA). The patient was diagnosed with cardiogenic cerebral embolism, and immediately underwent mechanical thrombectomy (MT), thereby complete recanalization was obtained. Post-procedural MRI showed no new lesions, and the left PCA could keep patency. His consciousness disorder and tetraplegia improved; however, cognitive impairment and vertical gaze palsy persisted as sequelae. To the best of our knowledge, such cases have not been previously reported. Additionally, in this case, we were able to identify an AOP on digital subtraction angiography, which was considered to be the responsible artery.

Asymmetric posterior reversible encephalopathy syndrome secondary to epilepsy occurring in the chronic phase of subarachnoid hemorrhage.

Background: Posterior reversible encephalopathy syndrome (PRES) is a rare clinical syndrome that refers to a disorder with reversible subcortical vasogenic brain edema involving the parieto-occipital lobe, temporal lobe, basal ganglia, and its surroundings. Radiologically, it is characterized by symmetrical lesions; however, atypical findings have sometimes been reported. Case Description: A 79-year-old woman experienced subarachnoid hemorrhage (SAH) a year and a half previously before this hospitalization. She presented with sudden-onset coma, dacryorrhea, and moderate right hemiparesis and was taken to our hospital. Computed tomography showed no apparent abnormal acute lesions. Electroencephalography confirmed periodic lateralized epileptiform discharges in the left hemisphere. First, based on the findings, she was diagnosed with nonconvulsive status epilepticus and started antiepileptic therapy. Six days after admission, however, multiple asymmetric lesions were confirmed on magnetic resonance imaging. Considering that findings subsequently improved, we finally diagnosed her with asymmetric PRES secondary to epilepsy occurring in the chronic phase of SAH. Aphasia and right hemispatial neglect persisted as sequelae and she was transferred to a rehabilitation hospital with a modified Rankin scale of 3. Conclusion: Excessive elevation of blood flow in the hemisphere is inferred to lead to blood-brain barrier collapse and subsequent asymmetric PRES.

Acidic Region Residues 1680-1684 in the A3 Domain of Factor VIII Contain a Thrombin-Interactive Site Responsible for Proteolytic Cleavage at Arg1689.

Factor VIII (FVIII) is activated by thrombin-catalyzed cleavage at Arg372, Arg740, and Arg1689. Our previous studies suggested that thrombin interacted with the FVIII C2 domain specific for cleavage at Arg1689. An alternative report demonstrated, however, that a recombinant (r)FVIII mutant lacking the C2 domain retained >50% cofactor activity, indicating the presence of other thrombin-interactive site(s) associated with cleavage at Arg1689. We have focused, therefore, on the A3 acidic region of FVIII, similar to the hirugen sequence specific for thrombin interaction (54-65 residues). Two synthetic peptides, spanning residues 1659-1669 with sulfated Tyr1664 and residues 1675-1685 with sulfated Try1680, inhibited thrombin-catalyzed FVIII activation and cleavage at Arg1689. Treatment with 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide to cross-link thrombin with either peptide showed possible contributions of both 1664-1666 and 1683-1684 residues for thrombin interaction. Thrombin-catalyzed activation and cleavage at Arg1689 in the alanine-substituted rFVIII mutants within 1663-1666 residues were similar to those of wild type (WT). Similar studies of 1680-1684 residues, however, demonstrated that activation and cleavage by thrombin of the FVIII mutant with Y1680A or D1683A/E1684A, in particular, were severely or moderately reduced to 20 to 30% or 60 to 70% of WT, respectively. Surface plasmon resonance-based analysis revealed that thrombin interacted with both Y1680A and D1683A/E1684A mutants with approximately sixfold weaker affinities of WT. Cleavage at Arg1689 in the isolated light-chain fragments from both mutants was similarly depressed, independently of the heavy-chain subunit. In conclusion, the 1680-1684 residues containing sulfated Tyr1680 in the A3 acidic region also contribute to a thrombin-interactive site responsible for FVIII activation through cleavage at Arg1689.

Postoperative subdural hematoma with blood flow from an epidural hematoma through a tear at the suture point of an artificial dura substitute.

OBJECTIVE: We have recently seen cases of postoperative epidural and subdural hematomas after duraplasty with an artificial dura substitute. In these cases, the epidural hematoma flowed into the subdural space through a tear at the suture point of the artificial dura substitute. In this study, whether such hematomas are specific to a certain artificial dura substitute was investigated, and the cause and risk factors were examined. METHODS: In our institute, 46 patients underwent brain tumor extirpation with duraplasty with an artificial dura substitute; Gore-Tex and SEAMDURA were used as the artificial dura substitutes. Patients with postoperative hemorrhage after brain tumor extirpation with duraplasty with an artificial dura substitute were retrospectively analyzed. Moreover, suture strength was compared experimentally between Gore-Tex and SEAMDURA. RESULTS: In patients who underwent brain tumor extirpation with duraplasty with an artificial dura substitute, the rate of postoperative hemorrhage was 8.6%. Epidural and subdural hematomas were seen in four patients after tumor extirpation with duraplasty with SEAMDURA, but there were none with Gore-Tex. Exposure of the superior sagittal sinus at craniotomy, older age, and longer operative time were seen more frequently in patients with hematoma than in patients without hematoma. The strength of the suture point was significantly weaker with SEAMDURA than with Gore-Tex (P = 0.00016). CONCLUSIONS: Postoperative epidural and subdural hematomas seem to be specific for SEAMDURA and may be caused by the weak suture strength of SEAMDURA. In cases of duraplasty, a nonabsorbable artificial dura substitute may be suitable.

Investigation of the characteristics of headache due to unruptured intracranial vertebral artery dissection.

BACKGROUND AND PURPOSE: It is sometimes difficult to diagnose intracranial vertebral artery dissection in patients with headache as the only symptom. Knowledge of the characteristics of the headache would facilitate the diagnosis. In this study, we aimed to clarify the characteristics of intracranial vertebral artery dissection-related headache using our original self-administered questionnaire. METHODS: Via the questionnaire, we ascertained headache characteristics and investigated whether they differed between two types of unruptured intracranial vertebral artery dissection, headache type and ischemic type, based on analysis of the responses. Then, we tried to validate the consistency of commonly used criteria for intracranial artery dissection by comparing them with our results. RESULTS: Thirty-seven patients were analyzed. Our results identified the following seven headache characteristics in patients with intracranial vertebral artery dissection: (i) occurring in the occipitonuchal region (89%); (ii) unilateral (81%); (iii) pulsatile (70%); (iv) of acute onset (70%); (v) severe (73%); (vi) without nausea or vomiting (73%); and (vii) with concomitant clinical symptoms unrelated to ischemia (81%). Comparison of headache characteristics between the two types of intracranial vertebral artery dissection headache showed that the pain was significantly more severe in headache type than ischemic type intracranial vertebral artery dissection ( p = 0.01). Concomitant clinical symptoms occurred significantly more often in ischemic type than headache type intracranial vertebral artery dissection ( p = 0.03). Our results generally satisfied the established headache diagnostic criteria. CONCLUSION: The pain characteristics of headache type and ischemic type intracranial vertebral artery dissection shown in our study may facilitate its diagnosis.

Endoscopic Hematoma Evacuation for Acute Subdural Hematoma in the Elderly: A Preliminary Study.

AIM: Endoscopic surgery for acute subdural hematoma (ASDH) has recently been performed in elderly patients. Unlike other reported procedures, we used the endoscope's fixation device to ensure hemostasis because the surgeon can then use a surgical instrument with each hand. To date, there have no reports that prove lesser invasiveness or noninferiority of endoscopic surgery based on direct comparison with a large craniotomy. In this study, we investigated whether our endoscopic procedure was effective and safe. MATERIALS AND METHODS: We performed 6 cases of endoscopic surgical procedures in elderly patients over the past year. First, our surgical outcomes were evaluated. Second, the outcomes were compared between our endoscopic surgery and our large craniotomy procedures. Third, the outcomes were compared between our endoscopic surgery and other reported endoscopic surgeries. RESULTS: The outcomes of our endoscopic surgery were generally satisfactory without complications or rebleeding. Mean hematoma evacuation percentage was 91.6 ± 4%. Compared with a large craniotomy, operative time was significantly shorter ( P = .01), and the hospital costs were significantly less for endoscopic surgery ( P = .008). There was no inferiority of outcomes when compared with other reported endoscopic surgeries. CONCLUSION: Our surgical procedure is safe and effective when performed with strict operative indications. Endoscopic surgery for ASDH in elderly adults may be an alternative to a large craniotomy in simple-type hematomas.

Which surgical procedure is effective for refractory chronic subdural hematoma? Analysis of our surgical procedures and literature review.

Refractory chronic subdural hematoma (CSDH) is rare but remains a difficulty for neurosurgeons, and no consensus on treatment procedures has been established. To discuss effective surgical procedures for refractory CSDH, we analyzed our surgical procedures and outcomes for refractory CSDH. We defined patients with refractory CSDH as those who presented with two or more recurrences. Fourteen patients with refractory CSDH were analyzed. Eight patients underwent burr-hole irrigation and closed-system drainage alone, four patients received embolization of the middle meningeal artery (MMA), and two patients with organized CSDH underwent large craniotomy with outer membranectomy as the third surgery. Two of the eight patients (25%) treated with burr-hole irrigation and drainage alone showed a third recurrence. No further recurrences were identified in patients treated with embolization of the MMA or craniotomy. However, statistical analysis showed no significant difference in cure rate between patients treated with burr-hole irrigation and drainage alone and patients treated with burr-hole irrigation and drainage with embolization of the MMA (P = .42). Similarly, no significant differences in cure rate were seen between patients treated with burr-hole irrigation and drainage alone and patients treated with craniotomy (P = .62). When selecting a surgical procedure, assessing whether the CSDH is organized is crucial. Embolization of the MMA may be considered as one of the optional treatments for refractory CSDH without organized hematoma. On the other hand, for refractory cases of organized CSDH, hematoma evacuation and outer membranectomy with large craniotomy or mini-craniotomy assisted by an endoscope may be suitable, as previous reports have recommended.

Clinical investigation of chronic subdural hematoma with impending brain herniation on arrival.

Chronic subdural hematoma (CSDH) with brain herniation signs is rarely seen in the emergent department. As such, there are few cumulative data to analyze such cases. In this study, we evaluated the clinical features, risk factors, and rates of completion with impending brain herniation on arrival in a cohort study. We analyzed 492 consecutive patients with CSDH between January 2010 and October 2015. First, we analyzed the clinical factors and compared them between patients with or without brain herniation signs on admission. Second, we compared clinical factors between patients with or without completion of brain herniation after operation among patients who had brain herniation signs on arrival. Eleven (2.2%) patients showed brain herniation signs on arrival, and six patients (1.2%) progressed to complete brain herniation. Patients with brain herniation signs on arrival were significantly older (P = 0.03) and more frequently hospitalized with a concomitant illness (P < 0.0001). Niveau formation (P = 0.0005) and acute-on CSDH (P = 0.0001) on computed tomography were also more frequently seen in patients with brain herniation signs. Multivariate logistic regression analysis showed that age older than 75 years (OR 2.16, P < 0.0001), niveau formation (OR 3.09, P < 0.0001), acute-on CSDH (OR 14, P < 0.0001), and admitted to another hospital (OR 52.6, P < 0.0001) were independent risk factors for having had brain herniation signs on arrival. On the other hand, having a history of head injury (P = 0.02) and disappearance of the ambient cistern (P = 0.0009) were significantly associated with completion of brain herniation. The prognosis was generally poor if the patient had presented with brain herniation signs on admission. Our results demonstrate that the diagnosis is often made late, despite hospitalization for a concomitant illness. When the elderly show mild disturbance of consciousness, physicians except neurosurgeons need to consider the possibility of CSDH regardless of a recent history of head injury.

Clinical Investigation of Refractory Chronic Subdural Hematoma: A Comparison of Clinical Factors Between Single and Repeated Recurrences.

BACKGROUND: Chronic subdural hematoma (CSDH) is sometimes refractory, and this is troublesome for neurosurgeons. Although many studies have reported risk factors or treatments in efforts to prevent recurrence, those have focused on single recurrence, and few cumulative data are available to analyze refractory CSDH. METHODS: We defined refractory CSDH as ≥2 recurrences, then analyzed and compared clinical factors between patients with single recurrence and those with refractory CSDH in a cohort study, to clarify whether patients with refractory CSDH experience different or more risk factors than patients with single recurrence, and whether burr-hole irrigation with closed-system drainage reduces refractory CSDH. RESULTS: Seventy-five patients had at least 1 recurrence, with single recurrence in 62 patients and ≥2 recurrences in 13 patients. In comparing clinical characteristics, patients with refractory CSDH were significantly younger (P = 0.04) and showed shorter interval to first recurrence (P < 0.001). Organized CSDH was also significantly associated with refractory CSDH (P = 0.02). Multivariate logistic regression analysis identified first recurrence interval <1 month (odds ratio, 6.66, P < 0.001) and age <71 years (odds ratio, 4.16, P < 0.001) as independent risk factors for refractory CSDH. On the other hand, burr-hole irrigation with closed-system drainage did not reduce refractory CSDH. CONCLUSIONS: When patients with risk factors for refractory CSDH experience recurrence, alternative surgical procedures may be considered as the second surgery, because burr-hole irrigation with closed-system drainage did not reduce refractory CSDH in our study.

Newly Detected Cervical Spinal Dural Arteriovenous Fistula on Magnetic Resonance Angiography Causing Intracranial Subarachnoid Hemorrhage.

BACKGROUND: Although an asymptomatic spinal dural arteriovenous fistula (SDAVF) can sometimes be incidentally detected on magnetic resonance imaging (MRI), there are no previous reports showing the development of an SDAVF on MRI or magnetic resonance angiography (MRA). CASE DESCRIPTION: A 64-year old man with unruptured vertebral artery dissection (VAD) developed a subarachnoid hemorrhage (SAH) during regular follow-up. Emergent endovascular coil internal trapping for the VAD was performed; however, angiography after the endovascular treatment showed a lower cervical SDAVF. The SDAVF was considered the bleeding source based on subsequent spinal MRI, and endovascular embolization was performed. In this case, previous serial MRA examinations indicated that the SDAVF appeared for the first time during follow-up, and SAH occurred. CONCLUSIONS: This may be the first report in which serial MRA studies demonstrated the course of this condition, from the appearance of an SDAVF to the development of SAH. An abnormal vascular structure detected on MRA indicated abnormal enlargement of the perimedullary vein and the presence of a cervical SDAVF. A lower cervical SDAVF should be suspected if such an abnormal vascular structure is detected on MRA.

Cerebellar Enterogenous Cyst with Atypical Appearance and Pathological Findings.

BACKGROUND: Intracranial enterogenous cysts are rare and occur mainly in the posterior fossa. These cysts are usually extra-axial, midline, anterior to the brainstem, or at the cerebellopontine angle. Intracranial intra-axial enterogenous cysts are extremely rare. We report a case of an intra-axial cerebellar enterogenous cyst in which diagnosis was difficult because the lesion resembled an arachnoid cyst in appearance and showed atypical pathologic findings. CASE DESCRIPTION: A 69-year-old woman had a 2-year history of progressive headache, giddiness, and unsteadiness of gait. Magnetic resonance imaging showed a cystic lesion with isointensity to cerebrospinal fluid in the left cerebellar hemisphere, reaching into the fourth ventricle. The patient underwent fenestration of the cyst and creation of a communication between the fourth ventricle and cyst because the tight attachment of the cyst wall to the cerebellum prevented total removal of the cyst. Although pathologic examinations did not show findings typical of enterogenous cyst, the diagnosis was finally made based on the presence of basement membrane and immunohistochemical results. CONCLUSION: The diagnosis of enterogenous cyst is based mainly on histologic findings, because characteristic findings on neuroimaging have not been defined. Although total resection of enterogenous cysts is recommended in general, partial resection while ensuring the cyst communicates adequately with the surrounding cerebrospinal fluid space with or without a shunt procedure may be useful if the cyst is adherent to surrounding neurovascular structures.

Development of Glioblastoma after Treatment of Brain Abscess.

OBJECTIVE: Abscess formation within a glioblastoma has been reported rarely. In the few reported cases, after aspiration to treat a presumed abscess, lesions recurred over a short period and, consequently, glioblastoma was recognized. We present a case of a glioblastoma that developed 1.5 years after successful treatment of a brain abscess. A latency of 1.5 years before symptom development seems overly long, even if the glioblastoma was present at the time of the initial brain abscess. Hence, we consider this a possible de novo glioblastoma arising from glial scar tissue. We also discuss possible mechanisms underlying malignant transformation. CASE DESCRIPTION: A 78-year-old man was admitted to our hospital with progressive gait disturbance caused by a brain abscess. Aspiration of the cyst and systematic antibiotic therapy cured the abscess. However, 1.5 years later, the patient presented to our hospital with generalized convulsions due to recurrence of the cystic lesion. He underwent craniotomy for removal of the cystic lesion, which was found to be a glioblastoma rather than a recurrent brain abscess. Glial scar tissue was detected in the cyst wall. CONCLUSIONS: Development of glioblastoma after treatment of a brain abscess is rare; the pathogenesis is open to speculation. Based on the clinical course, the pathologic findings, and comparison with previous reports, de novo glioblastoma arising from glial scar tissue may be the most likely explanation of the current case. If so, to our knowledge, this is the first report of this condition.

Lhermitte-Duclos Disease Treated Surgically in an Elderly Patient: Case Report and Literature Review.

A 75-year-old man with Lhermitte-Duclos Disease (LDD) manifesting as progressive headache is presented. Magnetic resonance imaging demonstrated a right cerebellar mass lesion with the characteristic "tiger-striped appearance". A mild mass effect was evident at the medulla oblongata, accompanied by inferior displacement of the right cerebellar tonsil. Thus, tonsillar herniation was considered the cause of his headache and he underwent partial resection of the tumor to solve tonsillar herniation. His headache gradually improved. LDD in the elderly is quite rare. Several differences in the nature of the lesion are seen in the elderly, with tendencies toward a male predominance, hypervascularity, and low rates of association with Cowden disease. Moreover, partial resection to reduce mass effect can improve clinical symptoms without recurrence. In symptomatic LDD in the elderly, to avoid surgical complication, we recommend partial resection to reduce mass effect.

Use of a microchip flow-chamber system as a screening test for platelet storage pool disease.

Platelet storage pool disease (SPD) is a platelet function disorder characterized by a reduction in the number or content of α-granules, dense granules, or both, and is diagnosed by specialized tests. Patients with SPD often present with prolonged bleeding time (BT), but the sensitivity and reproducibility of this test have limitations, often resulting in false negatives. It has recently been reported that an automated microchip flow-chamber system (T-TAS(®)) is useful in the assessment of anti-platelet therapy, and could have potential as a screening test for SPD. We examined the utility of T-TAS in three individuals from one family diagnosed with δ-SPD. The propositus had a mildly prolonged BT, and the standard tests for platelet function were close to the normal range. Whole blood samples were anti-coagulated with hirudin and applied to T-TAS microchips coated with collagen (PL-chips) at shear rates of 1000 and 2000 s(-1). Platelet thrombus formation (PTF) was monitored with a pressure sensor. Markedly depressed PTF was observed in all cases at both shear rates. These findings indicate that T-TAS is highly sensitive to the defect in these patients with SPD, and may represent a good candidate screening test for a wide range of platelet function disorders.

Radiation-induced cerebral aneurysm treated with endovascular coil embolization. A case report.

Radiation-induced cerebral aneurysms are rare. We describe a case of radiation-induced cerebral aneurysm successfully treated with endovascular coil embolization. A 39-year-old man received 60 Gy of radiation to a pineal germinoma at eight years old. The left internal carotid artery (ICA) aneurysm which developed within the irradiated field and stenotic change in the left ICA due to radiation-induced vasculopathy were detected incidentally. Because these aneurysms show a high risk of rupture and mortality, and even small aneurysms are prone to rupture, any such suspected aneurysm should be treated with surgical or endovascular procedures. Endovascular treatment is probably useful if the aneurysm is inaccessible to direct surgery. Special attention must be paid to treatment because of stenotic changes in cerebral vessels within the irradiated field.

Spontaneous spinal epidural hematoma with hemiparesis mimicking acute cerebral infarction: two case reports.

CONTEXT: Acute hemiparesis is a common initial presentation of ischemic stroke. Although hemiparesis due to spontaneous spinal epidural hematoma (SSEH) is an uncommon symptom, a few cases have been reported and misdiagnosed as cerebral infarction. DESIGN: Case reports of SSEH with acute hemiparesis. FINDINGS: In these two cases, acute stroke was suspected initially and administration of intravenous alteplase therapy was considered. In one case, the presentation was neck pain and in the other case, it was Lhermitte's sign; brain magnetic resonance imaging (MRI) and magnetic resonance angiography were negative for signs of ischemic infarction, hemorrhage, or arterial dissection. Cervical MRI was performed and demonstrated SSEH. CONCLUSION: Clinicians who perform intravenous thrombolytic treatment with alteplase need to be aware of this possible contraindication.