Medial tentorial dural arteriovenous fistula with venous sinus thrombosis leading to thalamic dementia: a challenging diagnosis of 4 cases / 国际脑血管病杂志

ABSTRACT

Objective:To investigate the imaging characteristics and diagnosis of thalamic dementia caused by medial tentorial dural arteriovenous fistula (TDAVF).Methods:The clinical and imaging data of 4 patients with medial TDAVF diagnosed at Nanjing Brain Hospital from August 2022 to September 2023 were retrospectively collected, summarized and analyzed.Results:Four patients were all males, with an average age of 67 years. The duration of cognitive impairment varies from 13 days to 2 months, with an average of about 1 month. The average score on the Mini-Mental State Examination (MMSE) was 13, while the average score on the Montreal Cognitive Assessment (MoCA) was 15. One patient was unable to complete these tests. MRI showed bilateral thalamic swelling, with scattered microbleeding lesions on diffusion-weighted imaging and susceptibility-weighted imaging ( n=3). Enhanced scans showed patchy or clumpy enhancement of the bilateral thalamus. Magnetic resonance angiography showed abnormal blood vessels along the straight sinus area ( n=4), while magnetic resonance venography showed no straight sinus development ( n=4). Magnetic resonance spectroscopy showed neuronal swelling and damage ( n=3), with no increase in choline peak. Arterial spin labeling perfusion imaging showed decreased perfusion in the lesions. Digital subtraction angiography confirmed TDAVF with straight sinus thrombosis. Two patients underwent embolization, with significant improvement in postoperative memory impairment. One patient underwent surgical clipping, while the other was transferred to other hospital for treatment. Conclusions:Patients with medial TDAVF often present with thalamic dementia. Imaging examinations show typical bilateral thalamic swelling with microbleeds, and early visualization of vascular shadows, without development of straight sinus. These features would be beneficial for the early diagnosis of TDAVF.