A 45-year-old man was admitted for a progressively worsening headache over 2 weeks. He denied history of recent head trauma or anticoagulation and antiplatelet medication. General and neurologic examinations were not remarkable on admission. Routine laboratory investigations including coagulation profiles and platelet function were within normal limits. Head computed tomography (CT) on admission revealed an isodense CSDH on the right hemisphere with mild midline shift (Fig. a). A CT angiography (CTA) was performed to rule out any intracranial vascular malformation. A DAVF was noticed at the transverse sinus with dilated cortical venous drainage (Fig. b). So, a digital subtraction angiography (DSA) of the external carotid artery and DAVF embolization was planned.\nNo anomaly was noticed during selective angiography of the internal carotid and vertebral arteries and the left external carotid artery. Selective angiography of the right external carotid artery showed that the DAVF was located at the transverse sinus and fed by posterior branch of the middle meningeal artery (MMA), the occipital artery, and the posterior meningeal artery and drained to the occipital cortical veins with venous ectasia (Fig. a-b). The DAVF was classified as type IV according to the Cognard classification. The embolization was performed via the MMA. The Headway duo catheter was used and accessed to the DAVF, and Onyx was injected until the shunt disappeared (Fig. c-d). The patient experienced an uneventful recovery. His CSDH gradually resolved in 1 month (Fig. ). No neurologic deficit was noticed.\nA PubMed search of published studies written in English and Chinese was conducted on June 30th, 2017. The following key words were used in relevant combinations: dural arteriovenous fistula, dural arteriovenous malformation, subdural hematoma, subdural haematoma, subdural hemorrhage, and subdural haemorrhage. The reference lists of the identified articles were also manually searched for additional studies. Studies of which full text could not be obtained or those without sufficient individualized description of the isolated SDH cases mixed in larger case series were excluded.\nFinally, 13 articles containing 14 patients were identified [–]. In all 15 patients (9 females, 60%) including 1 case in our institution were included for the final interpretation (Table ). The inflicted patients were aged from 27 to 82 years (55.5 ± 8.6).Of note, 12 (80%) of the 15 patients were aged between 40 and 60 years of age, and 8 (53.3%) patients were between 50 and 60 years. Sides of the DAVF or SDH were obtained in 13 patients with 9 (69.2%) located at the left side and 4 at the right side. The intracranial locations of DAVF were anterior fossa (2), middle fossa (2), frontal region (2), parietal region (3), temporal region (2), and occipital region (2). The types of SDH were CSDH (7/15), acute SDH (ASDH) (7/15), and undefined SDH (1/15). Of the 12 patients feeding artery could be identified, MMA was the commonest feeding artery (8/12, 66.7%). Multiple feeding arteries were identified in 3 (25%) patients. The causes of DAVF were only defined in 3 patients (2 iatrogenic and 1 traumatic), with the rest undefined or not mentioned. Cognard classifications (Table ) of the DAVF were reported or deduced from the reports in 12 patients, with type I, type III, and type IV in 7, 2, and 3 patients respectively. The treatment strategies included hematoma evacuation (2/15), CSDH drainage and DAVF embolization (5/15), craniotomy and DAVF resection (3/15), DAVF embolization and hematoma evacuation (1/15), DAVF embolization (2/15), and not applicable or not mentioned (2/15). Of the 12 patients with direct description of outcome, 7 (58.3%) patients were neurological intact, 3 (25%) patients with neurological deficits, and 2 (16.7%) died.
A 58-year-old right-handed postmenopausal woman presented to the emergency with progressively increasing holocephalic headache for 3 days. She did not have fever, nausea, and vomiting. The headache gradually worsened in severity and on the day of presentation, she developed a generalized tonic clonic seizure. Apart from the history of well-controlled diabetes mellitus, she did not have significant past medical, personal, and family history. She had not received any vaccines in the recent past. On examination, she was ill-looking, but her vital signs were stable. She had Wernicke's aphasia. She did not have disc edema; cranial nerve examination was normal, and she did not have any focal deficits.\nAn urgent CT scan of the head without contrast showed left temporal hematoma with surrounding vasogenic edema (Figure ). Hemorrhagic picture was noted in the insular cistern (Figure ), left fronto-temporal subdural space (Figure ), the perimesencephalic, ambient and suprasellar cisterns (Figures and ), and the sulci of the left temporo-parietal lobes (Figures and ). There was a subtle dense clot sign in the left transverse sinus (Figure ). She was diagnosed as having left transverse sinus thrombosis leading to left temporal hematoma, SAH and SDH. She was treated with low molecular weight heparin, levetiracetam, and 3% hypertonic saline. The magnetic resonance venography (MRV) done the following day confirmed the presence of left transverse sinus thrombosis (Figure ). CT angiography of the brain did not reveal any vascular malformations. Her complete blood counts, coagulation profiles, routine blood chemistry, and C-reactive protein were within normal limits. Antinuclear antibody and SARS-CoV-2 RNA polymerase chain reaction tests were negative. She underwent CT scan of neck, chest, abdomen and pelvis, mammogram, stool occult blood, carcinoembryonic antigen, CA-125, and Ca 19–9 tests, all of which were non-contributory to any occult malignancy. Thrombophilia screening was not done at this acute stage. We decided to get those done after the completion of anticoagulant treatment. She showed good clinical improvement over the course of the next few days. A repeat CT scan of the head done on day seven, revealed decreasing edema and stable hematoma volume with no new bleeding. The cause of her CVST was deemed undermined at this stage and she was discharged home on dabigatran 150 mg twice daily, as she could not get PT/INR done reliably due to the current lockdown imposed by the government. She has been doing well on follow up.