A rare case of sacral epidural arteriovenous fistula with concomitant occult multiple lumbar epidural arteriovenous fistulas.

We describe a rare case of sacral epidural arteriovenous fistulas (edAVFs) with atypical clinical course of treatment. A 78-year-old man with a history of spinal surgery presented progressive gait disturbance and urinary incontinence. Spinal angiography demonstrated a sacral spinal AVF fed by bilateral lateral sacral arteries, draining to the venous pouch with subdural drainage. The first treatment by direct interruption of a subdural drainer was incompletely finished. Postoperative reassessment by 3D imaging analysis led to the diagnosis of sacral edAVF and 3D understanding of its angioarchitecture. The second treatment by transarterial embolization (TAE) resulted in complete occlusion of a sacral edAVF. However, spinal venous congestion didn't improve, because the recruitment of occult edAVFs at the multiple lumbar levels and complex-shaped sacral ventral epidural venous plexus (VEP) were involved in the remnant of prior subdural drainage. The third treatment was performed by TAE for three occult edAVFs and the VEP compartment connecting between a patent edAVF and subdural drainage, which resulted in complete disappearance of spinal cord edema. Endovascular embolization of VEP compartment connecting to subdural drainage in addition to fistulous occlusion may be one of the treatment options for several edAVFs at the multiple spinal levels.

Role of Endovascular Approach as Diagnostic Technique and First-Line Therapy for the Patients with Micro-Arteriovenous Malformations: A Case Report and Literature Review.

Objective: We describe a rare case report of micro-arteriovenous malformation (micro-AVM) treated by the endovascular approach in addition with literature review. Case Presentation: A 12-year-old boy presenting with a spontaneous intracerebral hematoma in the left occipital lobe underwent conventional diagnostic workups. The results of initial catheter angiography were considered to be equivocal as the AVM. Superselective angiography (SA) demonstrated a micro or small AVM (single feeder and single drainer type) with an aneurysmal dilatation. Immediate transarterial embolization (TAE) might fail to occlude the whole of nidus area completely, and subsequently, we switched to the surgical exploration of AVM lesion. Intraoperative findings demonstrated that the whole of AVM lesion had already been occluded completely, indicating the complete occlusion by TAE only. Pathological findings of the surgical specimen showed an aneurysmal dilatation was a venous aneurysm with vulnerable vascular wall structure, which was certainly the source of bleeding. Based on the above results, the retrospective revaluation of superselective angiogram permitted us to understand that the nidus of AVM was micro nidus type and TAE had resulted in the complete nidus occlusion. Conclusion: SA is the most useful diagnostic modality to clarify the angioarchitecture of micro-AVM and AVM-related aneurysms. If SA is successfully performed and relatively safe TAE is expected to be possible, the subsequent attempt to do curative embolization as a first-line treatment may be worthy of consideration. However, the surgical procedure should be fully reserved for the possible incomplete obliteration and hemorrhagic complications.

Traumatic brain injury among two-wheeled motor vehicle riders in Utsunomiya, Japan: a comparison between mopeds and motorcycles.

PURPOSE: Two-wheeled motor vehicles are dichotomized into mopeds and motorcycles (MCs) based on their engine capacity. While efforts have been made, mostly by European researchers, to evaluate the possible difference in the frequency/severity of riders' traumatic brain injury (TBI) between the two categories, the results have been inconsistent. METHODS: To evaluate whether such differences exist in Japan, a single-center, retrospective observational study was conducted on two-wheeled motor vehicle riders wearing a helmet during high-energy road traffic accident (RTA). Between January 2011 and December 2017, 127 moped and 128 MC helmeted riders involved in RTAs had been treated in our institution. RESULTS: Moped riders were significantly older than MC riders (50.7 ± 25.0 years vs. 35.1 ± 18.6 years, p = 0.04). The frequency of TBI was significantly higher in moped riders than in MC riders (21.3% vs. 10.9%; p = 0.03). However, the frequency of other bodily injuries did not differ significantly. Among the riders with TBI, neither injury severity nor outcomes differed significantly. Multivariate regression analysis showed that the presence of altered mental status was predictive of TBI (OR 23.398; 95% CI 9.187-59.586; p < 0.001). Moped riders trended to have a higher likelihood of sustaining TBI (OR 2.122; 95% CI 0.870-5.178; p = 0.098). CONCLUSIONS: Mopeds are frequently utilized by elderly in Japan, which may have been causally associated with the higher frequency of TBI in moped riders, while other causes, including the difference in helmet type, may also be involved. This study is limited by its small sample size and retrospective design, and multi-center prospective studies are warranted.

Clinical Characteristics of Driving-related Stroke Occurring as a Recurrent Stroke.

BACKGROUND: Although the number of seemingly healthy subjects who suffer a minor stroke increases, there are no data on how frequently they sustain another stroke while driving. METHODS: A single-center, retrospective study was conducted to clarify the clinical characteristics of driving-related stroke occurring as a recurrent stroke by analyzing data prospectively acquired between January 2009 and June 2019 on 3452 acute stroke patients. RESULTS: One hundred-thirty five patients (85 ischemic stroke [IS] and 50 hemorrhagic stroke [HS]) had suffered a driving-related stroke. Of them, 22 (16%) had suffered a prior stroke (recurrent stroke group), while 113 had never suffered a stroke before (first-time stroke group). While the use of anti-thrombotics was significantly more common in the RS group, other variables including the frequency of road traffic accidents, did not differ significantly. The first stroke-recurrent stroke interval ranged from 0.2 to 18 years. The stroke type at the time of recurrence was IS in the majority of patients with prior IS. When compared to 432 patients with recurrent IS unrelated to driving, patients with recurrent IS related to driving (n = 16) had significantly higher frequency of lacunar strokes (56% vs 27%, P = .02) and lower frequency of cardioembolic strokes (6% vs 29%, P = .04). CONCLUSION: The current finding that 16% of patients who presented with driving-related stroke had previously suffered a stroke indicates that drivers with a prior stroke may be at increased risk for recurrent stroke while driving, and prolonged follow-up be necessary for minor stroke patients who resume driving.

Cerebrospinal Fluid Leakage at the Lumbar Spine: A Unique Cause of Delayed Neurologic Deterioration in a Traumatic Acute Subdural Hematoma Patient.

We present a rare case of traumatic acute subdural hematoma (SDH) in which intracranial hypotension (IC) secondary to cerebrospinal fluid (CSF) leakage at the lumbar spine caused delayed neurological deterioration. A 70-year-old male sustained a head injury after ground-level fall and was brought to our institution. A brain computed tomography (CT) showed a thin acute SDH with mild brain shift, and conservative management was initiated. He exhibited neurological deterioration on the 9th hospital day, however, and a brain CT showed a change in CT density and marked an increase in hematoma volume and brain shift. It was thought that conversion from acute to subacute SDH was associated with the deterioration, and emergency hematoma evacuation was performed. Despite the surgery, neither clinical nor radiographical improvement occurred. The lack of improvement pointed to the presence of underlying IC, and a CT myelography revealed the dural sleeve of the right L2 nerve root as the source of the CSF leakage. An epidural blood patch therapy was performed on the 12th hospital day to seal the CSF leakage. The postprocedural course was uneventful, and the patient was discharged free of symptoms on the 20th hospital day. Spinal CSF leakage should be considered as a cause of delayed neurological deterioration in patients with traumatic acute SDH which exhibits conversion to subacute SDH.

Seizures occurring while driving in patients with and without diagnosis of epilepsy: Frequency and association with automobile accidents.

Seizure may occur during any human activity, including driving. The objectives of this study were to report the frequency of seizure occurring while driving, clarify patient characteristics and analyze the behavioral patterns of drivers afflicted by seizure. A single-center, retrospective study was conducted using prospectively acquired data. Data of 658 adult seizure patients who visited our emergency department between January 2011 and December 2016 were used for analysis, focusing on daily activities immediately before seizure. Nineteen of the 658 patients (2.9%) sustained seizure while driving. The 658 patients were dichotomized on the basis of whether he or she had been diagnosed with epileptic seizure (ES). Seven of the 307 patients with ES vs. 12 of the 351 patients without ES sustained seizure while driving. The frequencies did not differ significantly between the two groups (2.3% vs. 3.4%, p = 0.49). Structural lesions on brain imaging studies were found in 6 of the 12 patients without ES (50%). Sixteen of the 19 patients (84%) caused automobile accidents after seizure. Among the 7 patients with ES, antiepileptic drugs had not been prescribed in 3 (43%). Although seizures occurring while driving have been studied extensively, most researchers focused on patients with ES. This study was unique because it focused on patients without ES, and the current findings that seizures in patients without ES outnumbered seizures in those with ES may be informative to clinical neuroscientists and emergency physicians. Prospective studies are expected to identify individuals at risk for first seizure occurring while driving.

Frequency and characteristics of traumatic brain injury in restrained drivers involved in road traffic accidents.

BACKGROUND: While seatbelt is an important device protecting drivers from traumatic brain injury (TBI), it has rarely been reported how often and in what circumstances restrained drivers sustain TBI after road traffic accident (RTA). Whole-body computed tomography (WBCT) for blunt trauma patients may provide a unique opportunity to investigate the frequency and characteristics of TBI sustained by restrained drivers. METHODS: A single-center, retrospective observational study was conducted using prospectively acquired data. Between January 2013 and December 2017, 409 restrained drivers (284 men/125 women, mean age of 45.0 ± 19.1 years) whose vehicle had been severely damaged in RTAs underwent WBCT for evaluation of injuries. Multivariate regression analysis was performed to identify variables predictive of TBI. Influence of collision patterns (frontal, lateral or rollover) on the frequency and severity of TBI was evaluated. Relationship between collision patterns and CT findings was also reviewed. RESULTS: Thirty-one restrained drivers (7.6%) sustained TBI after RTA. The distribution of Glasgow Coma Scale (GCS) scores among the 31 drivers was 15 in 9, 13-14 in 9, 9-12 in 4, and ≤ 8 in 9, indicating that the majority of TBIs were classifiable as mild. The frequency of TBI in alert and oriented drivers, i.e., those with a GCS score of 15, was 2.9%. Multivariate regression analysis showed that both altered mental status (OR, 4.933; 95% CI, 1.135-21.431) and loss of consciousness (OR, 6.492; 95% CI, 1.669-25.249) were associated with TBI. The frequency of TBI tended to be higher in drivers with rollover collision than those with frontal collision (6 vs. 13%, p = 0.07). Interhemispheric acute subdural hematoma and subcortical petechial hemorrhage seemed to be characteristic CT findings in drivers with frontal and lateral collision, respectively. CONCLUSIONS: The key finding of this study, i.e., that (1) TBI was observed in 7.6% of restrained drivers with severe vehicular damage, may provide useful information to neurosurgeons who take care of RTA victims. The majority of the TBIs were mild without need for neurosurgical intervention. While association may exist between type of collision and type of brain injury, further studies with prospective design are warranted.

Stroke while driving: Frequency and association with automobile accidents.

Background Cardiovascular events while driving have occasionally been reported. In contrast, there have been few studies on stroke while driving. Aim The objectives of this study were to (1) report the frequency of stroke while driving and (2) evaluate its association with automobile accidents. Methods Clinical data prospectively acquired between January 2011 and December 2016 on 2145 stroke patients (1301 with ischemic stroke, 585 with intracerebral hemorrhage, and 259 with subarachnoid hemorrhage) were reviewed to identify patients who sustained a stroke while driving. The ratio of driving to performing other activities was evaluated for each stroke type. Furthermore, the drivers' response to stroke was reviewed to understand how automobile accidents occurred. Results Among the 2145 patients, 85 (63 ischemic stroke, 20 intracerebral hemorrhage, and 2 subarachnoid hemorrhage) sustained a stroke while driving. The ratio of driving to performing other activities was significantly higher in ischemic stroke (4.8%) than in intracerebral hemorrhage (3.4%) or subarachnoid hemorrhage (0.8%). A majority of drivers either continued driving or pulled over to the roadside after suffering a stroke. However, 14 (16%) patients were involved in automobile accidents. In most patients, an altered mental status due to severe stroke was the presumed cause of the accident. Conclusion Stroke occurred while driving in 4.0% of all strokes and accidents occurred in 16% of these instances.

Clinical characteristics of stroke occurring in the toilet: Are older adults more vulnerable?

AIM: While autonomic imbalance during defecation/micturition can cause hemodynamic instability, stroke occurring in the toilet has rarely been investigated. The objective of the present study was to clarify the frequency and clinical characteristics of toilet-related stroke. METHODS: Clinical data prospectively acquired between January 2011 and December 2015 on 1939 patients with acute stroke (1224 cerebral infarctions [CI], 505 intracerebral hemorrhages [ICH] and 210 subarachnoid hemorrhages [SAH]) were reviewed to identify patients with a toilet-related stroke. For each stroke type, the ratios of stroke occurring during defecation/micturition to those occurring during other activities were calculated. Subsequently, how patients with toilet-related stroke were brought to medical attention was investigated. Whether older patients (aged >65 years) had an elevated ratio of toilet-related stroke was investigated in each stroke type. RESULTS: A total of 108 patients (41 CI, 37 ICH and 30 subarachnoid hemorrhages) sustained a stroke in the toilet. The ratio of toilet-related stroke was highest in subarachnoid hemorrhages (14.3%), followed by ICH (7.3%). Circadian differences existed among the three stroke types: toilet-related CI were more likely to occur in the night-time than ICH. Patients with toilet-related CI were significantly more likely to sustain cardioembolic stroke. In all three stroke types, <40% of patients could call for help by themselves. Older patients showed a significantly higher proportion of toilet-related stroke in CI, but not in hemorrhagic strokes. CONCLUSIONS: The toilet is a closed space where stroke occurs disproportionately frequently. Effort to reduce the incidence of toilet-related strokes is warranted, as early patient detection is not always feasible. Geriatr Gerontol Int 2018; 18: 250-255.

Comprehensive genetic characterization of rosette-forming glioneuronal tumors: independent component analysis by tissue microdissection.

A rosette-forming glioneuronal tumor (RGNT) is a rare mixed neuronal-glial tumor characterized by biphasic architecture of glial and neurocytic components. The number of reports of genetic analyses of RGNTs is few. Additionally, the genetic background of the unique biphasic pathological characteristics of such mixed neuronal-glial tumors remains unclear. To clarify the genetic background of RGNTs, we performed separate comprehensive genetic analyses of glial and neurocytic components of five RGNTs, by tissue microdissection. Two missense mutations in FGFR1 in both components of two cases, and one mutation in PIK3CA in both components of one case, were detected. In the latter case with PIK3CA mutation, the additional FGFR1 mutation was detected only in the glial component. Moreover, the loss of chromosome 13q in only the neurocytic component was observed in one other case. Their results suggested that RGNTs, which are tumors harboring two divergent differentiations that arose from a single clone, have a diverse genetic background. Although previous studies have suggested that RGNTs and pilocytic astrocytomas (PAs) represent the same tumor entity, their results confirm that the genetic background of RGNTs is not identical to that of PA.

Clinical Characteristics of Stroke Occurring while Bathing.

BACKGROUND: Stroke can occur during any human activity. Although cardiac arrests or drowning accidents while bathing have been studied extensively, there are few studies focusing on stroke occurring while bathing. The objectives of this study were to evaluate the clinical characteristics of stroke occurring while bathing and the association between stroke and drowning accidents. METHODS: Clinical data prospectively acquired between January 2011 and December 2015 on 1939 patients with stroke (1224 cerebral infarctions [CIs], 505 intracerebral hemorrhages [ICHs], and 210 subarachnoid hemorrhages [SAHs]) were reviewed to identify patients who sustained a stroke while bathing. The ratio of bathing-related strokes to strokes occurring during other activities was evaluated. Moreover, the demographics of these 2 groups were compared in each stroke type. RESULTS: Among the 1939 patients, 78 (CI, 32; ICH, 28; and SAH, 18) sustained a stroke while bathing. The ratio of bathing to other activities in the SAH group was the highest (8.6%), followed by the ICH group (5.5%), whereas that in the CI group was the lowest (2.6%). Regardless of stroke type, only a minority of patients were found to have collapsed inside the bathtub. CONCLUSIONS: The higher ratio of bathing in hemorrhagic strokes may indicate that there is a small risk of hemorrhagic stroke while bathing in vulnerable subjects. This retrospective study did not establish a causal relationship between bathing and stroke nor identify risk factors, which means that future prospective studies are warranted. The finding that the great majority of bathing-related stroke patients were found to have collapsed outside the bathtub suggests that the involvement of stroke in drowning accidents in the bathtub may be small.

Computed tomography evaluation of the brain and upper cervical spine in patients with traumatic cardiac arrest who achieved return of spontaneous circulation.

The outcomes of patients with traumatic cardiac arrest (TCA) have been dismal. However, imaging modalities are improving rapidly and are expected to play a role in treatment of patients with TCA. In this retrospective study, whether obtaining computed tomography (CT) immediately after resuscitation had any clinical value was evaluated. Among 145 patients with TCA admitted to our institution during 4 years, hemodynamically stable return of spontaneous circulation (ROSC) was achieved in 38 (26%). Brain and cervical spine CT was obtained prospectively, and the frequency and type of traumatic brain injury (TBI)/upper cervical spine injury (UCSI) were investigated. CT was performed uneventfully in all patients with an average door-to-CT time of 51.5 ± 18.6 min. Twenty (53%) had CT evidence of TBI. However, no patients underwent brain surgery because of lack of return of brainstem functions. Among the 18 patients without TBI, CT signs of hypoxia were present in 15 patients (39%), and CT was considered intact in 3 patients (8%). None of the 35 patients with abnormal CT findings survived, and the presence of such findings predicted fatality with high sensitivity and specificity. While 13 of the 38 patients (34%) had CT evidence of UCSI, concomitant TBI and USCI were uncommon. None of the 13 patients with UCSI underwent spine surgery because of lack of return of brainstem functions, and the presence of USCI might also be associated with fatality. Although obtaining CT was useful in the prognostication of TCA patients with ROSC, it did not have much impact in therapeutic decision making.

Early CT signs of hypoxia in patients with subarachnoid hemorrhage presenting with cardiac arrest: early CT signs in SAH patients presenting with CA.

BACKGROUND: For cardiac arrest (CA) victims, brain computed tomography (CT) may serve as a prognosticator. Loss of gray-white matter discrimination (GWMD) and sulcal edema/effacement are reliable CT signs of hypoxia, and a time window may exist for development of these signs. Most data are derived from CA victims of cardiac etiology, however, and CT signs have rarely been evaluated in victims of CA secondary to subarachnoid hemorrhage (SAH). METHODS: A retrospective study was conducted to clarify the incidence, temporal profile, and prognostic significance of early CT signs in resuscitated SAH-CA patients. RESULTS: During a 6-year period, 35 SAH-CA patients were identified. CT signs were observed in 94 %: loss of GWMD was observed in 94 %, whereas sulcal edema/effacement was observed in 77 %. In 29 patients, the interval between CA and the return of spontaneous circulation (ROSC) was estimated. CT signs developed almost invariably when the CA-ROSC interval exceeded 10 min. Loss of GWMD always preceded sulcal edema/effacement. None of the 35 patients achieved long-term survival, regardless of the presence of the CT signs. CONCLUSION: CT signs may develop earlier in patients with SAH-CA than CA of cardiac origin. Because of a poor prognosis, early CT signs are not useful prognosticators in that population.

Subarachnoid hemorrhage complicated with neurogenic pulmonary edema and takotsubo-like cardiomyopathy.

Patients with poor-grade subarachnoid hemorrhage (SAH) are often complicated with acute cardiopulmonary dysfunctions, particularly neurogenic pulmonary edema (NPE) and takotsubo-like cardiomyopathy (TCM). This study retrospectively investigated the incidence, demographics, clinical characteristics, and outcomes of patients with SAH complicated with both NPE and TCM (NPE-TCM). The effects of aneurysm location and other clinical variables on the incidence of NPE-TCM were also investigated. Among 234 SAH patients treated during 5-year period, 16 (7%) presented with NPE, and transthoracic ultrasonography revealed that 14 of these 16 patients (88%) also had TCM. All 14 patients with NPE-TCM had poor-grade SAH (World Federation of Neurosurgical Societies grades IV and V). Ruptured posterior circulation aneurysm was predictive of NPE-TCM, but other clinical variables were not. Eight of the 14 patients with NPE-TCM could undergo treatment for ruptured aneurysm. Long-term outcomes were favorable in 5 of the 8 patients. Grade IV SAH patients had significantly better outcomes than grade V patients. TCM develops frequently in SAH patients presenting with NPE, and transthoracic ultrasonography should be conducted routinely in that population. Patients with ruptured posterior circulation aneurysm may have elevated risk of developing NPE-TCM. Endovascular obliteration of the aneurysm may be preferable to open surgery, but the optimal treatment modality needs to be evaluated further. Considering the limited number of SAH patients complicated with NPE-TCM, a multi-center cooperative study may be required.

Influence of warfarin and low-dose aspirin on the outcomes of geriatric patients with traumatic intracranial hemorrhage resulting from ground-level fall.

AIM: Ground-level fall is the most common cause of traumatic intracranial hemorrhage (TICH) in the elderly, and is a major cause of morbidity and mortality in that population. A retrospective study was carried out to evaluate whether the use of warfarin/low-dose aspirin (LDA) is predictive of unfavorable outcomes in geriatric patients who sustain a fall-induced TICH. METHODS: Charts of 76 geriatric patients (≥ 65 years-of-age) with fall-induced TICH were reviewed. The number of patients taking warfarin and LDA was 12 and 21, respectively, whereas the other 43 took neither medication (non-user group). The frequency of patients with unfavorable outcomes (Glasgow Outcome Scale score of 1-3) at discharge was calculated. Furthermore, variables predictive of unfavorable outcomes were identified by logistic regression analysis. RESULTS: The frequency of patients with unfavorable outcomes was 75% in the warfarin group, 33% in the LDA group and 27% in the non-user group, respectively. The risk of having unfavorable outcomes was significantly higher in the warfarin group compared with the LDA group (P = 0.03) and non-user group (P < 0.01). Logistic regression analysis showed that variables predictive of unfavorable outcomes were: age, initial Glasgow Coma Scale score ≤ 13 and presence of midline shift ≥ 5 mm. CONCLUSION: The use of warfarin, but not of LDA, might be associated with unfavorable outcomes in elderly with fall-induced TICH. The risk of TICH should be communicated properly to elderly taking warfarin. The information might be important not only to trauma surgeons who take care of injured elderly, but also to geriatric physicians who prescribe warfarin/LDA to them.

Subarachnoid hemorrhage causing cardiopulmonary arrest: resuscitation profiles and outcomes.

Aneurysmal subarachnoid hemorrhage (SAH) is a common cause of cardiopulmonary arrest (CPA). The outcomes of SAH patients presenting with CPA are extremely poor, and long-term survivors have occasionally been reported, but the circumstances under which SAH-CPA patients achieve long-term survival are unclear. Neurosurgeons will have to determine whether a SAH-CPA patient is brain-dead or not more often after enactment of the revised Organ Transplantation Act. Prediction of survival length may be important not only to neurosurgeons, but also to the transplantation team. A retrospective study was conducted to elucidate how often brainstem function was recovered in resuscitated SAH-CPA patients and whether the recovery was associated with longer survival. Among 315 patients with non-traumatic SAH admitted to our institution during 6 years, 35 (11%) presented with CPA. Ventricular fibrillation (VF) as initial cardiac rhythm was rare, observed only in 1 patient. The survival length ranged from 1 to 15 days (mean 3.5 ± 0.7 days), and none achieved long-term survival. Return of brainstem function, represented by spontaneous respiration and/or reactive pupils, was observed in 6 patients (17%), but was only partial and transient. Cardiac arrest to return of spontaneous circulation interval tended to be shorter in patients with transient recovery of the brainstem function than in those without recovery. However, the survival length was not significantly different between the two groups. In addition to the 35 SAH-CPA patients, another 44 SAH patients lost both brainstem reflexes and spontaneous respiration within 72 hours of admission. As a result, 79 (25%) of the 315 SAH patients were considered to have sustained fatal, irreversible brain damage. Review of previous experience suggests that SAH-CPA patients may survive only if the cause of cardiac arrest is VF and not brainstem damage/respiratory arrest. Approximately one-third of resuscitated SAH-CPA patients may die within 24 hours of arrival, for whom the declaration of brain death may be difficult.

Spontaneous intracranial hypotension presenting without orthostatic headache complicated by acute subdural hematoma after drainage for chronic subdural hematoma--case report.

A 28-year-old man presented with a case of spontaneous intracranial hypotension (SIH) manifesting as a bilateral chronic subdural hematoma (CSDH) without orthostatic headache. He developed life-threatening acute SDH as a complication of CSDH drainage. Neurosurgeons should be aware that SIH patients do not always present with orthostatic headache. Brain magnetic resonance imaging with gadolinium may be recommended for young adults with non-traumatic CSDH before drainage to exclude SIH, even if they do not present with orthostatic headache.