Comparison between moyamoya disease and moyamoya syndrome in Israel.

BACKGROUND AND AIMS: Moyamoya is a chronic brain vasculopathy involving the distal intracranial internal carotid artery (ICA) or proximal middle cerebral artery (MCA). Moyamoya patients can be divided into those with primary moyamoya disease (MMD) and those with moyamoya secondary to other known causes such as intracranial atherosclerosis (moymoya syndrome [MMS]). Our aim was to compare the characteristics of MMD patients to those of MMS patients in a sample of Israeli patients seen over the course of 20 years at a tertiary referral center. METHODS: Included patients were diagnosed with either MMD or MMS based on typical imaging findings and the presence or absence of known concomitant vascular risk factors or associated disorders and vascular disease. Patients with MMS were compared to those with MMD. Demographics, symptoms, signs, and radiological data were compared between the groups. Treatment options and long-term rates of recurrent stroke and functional outcome were also studied. RESULTS: Overall, 64 patients were included (25 MMD, 39 MMS). Patients with MMD were significantly younger (median IQR 20 (7-32) vs. 40 (19-52); p=0.035). Patients with MMS more often had vascular risk factors but there were no significant differences in clinical presentations or long-term disability rates between the groups and a similar proportion of patients underwent surgical interventions to restore hemispheric perfusion in both groups (48% vs. 44% MMS vs. MMD; p=0.7). Almost one in four patient had a recurrent stroke after the initial diagnosis in both groups. Most recurrences occurred in the pre-surgery period in the MMS group and in the post-surgery period in the MMD group. CONCLUSIONS: There were no statistically significant differences in clinical or radiological presentations between the MMS and MMD patients. The course is not benign with recurrent stroke occurring in as many as 25%. More data is needed in order to identify those at high risk for stroke occurrence and recurrence.

Covid-19 associated free hanging clots in acute symptomatic carotid stenosis.

BACKGROUND: Thrombotic complications including stroke were previously described following Covid-19. We aim to describe the clinical and radiological characteristics of Covid-19 related with acutely symptomatic carotid stenosis (aSCS). METHOD: All patients presenting with an aSCS were prospectively enrolled in an ongoing institutional database. Inclusion criteria for the Covid-19-aSCS group were a combination of both antigen test and a positive reverse-transcriptase (PCR) test for Covid-19 upon admission. Patients with additional potential etiologies for stroke including cardioembolism, carotid dissection or patients with stenosis of <50% on CTA were excluded. A cohort of non-Covid-19 related aSCS patients admitted to the same institution before the pandemic during 2019 served as controls. RESULTS: Compared to controls (n = 31), Covid-19-aSCS (n = 8), were younger (64.2 ± 10.7 vs 73.5 ± 10, p = 0.027), and less frequently had hypertension (50% vs 90%, p = 0.008) or hyperlipidemia (38% vs 77%, p = 0.029) before admission. Covid-19-aSCS patients had a higher admission NIHSS score (mean 9 ± 7 vs 3 ± 4, p = 0.004) and tended to present more often with stroke (88% vs 55%, p = 0.09) rather than a TIA. Covid-19-aSCS patients had higher rates of free-floating thrombus and clot burden on CTA (88% vs 6.5%, p = 0.002). Covid-19 patients also less often achieved excellent outcomes, with lower percentage of mRS score of 0 after 90-days (13% vs 58%, p = 0.022). CONCLUSION: Covid-19- aSCS may occur in a younger and healthier subpopulation. Covid-19- aSCS patients may have higher tendencies for developing complex clots and less often achieve excellent outcomes.