Are morphologic features of recent small subcortical infarcts related to specific etiologic aspects?

BACKGROUND: Recent small subcortical infarcts (RSSIs) mostly result from the occlusion of a single, small, brain artery due to intrinsic cerebral small-vessel disease (CSVD). Some RSSIs may be attributable to other causes such as cardiac embolism or large-artery disease, and their association with coexisting CSVD and vascular risk factors may vary with morphological magnetic resonance imaging (MRI) features. METHODS: We retrospectively identified all inpatients with a single symptomatic MRI-confirmed RSSI between 2008 and 2013. RSSIs were rated for size, shape, location (i.e. anterior: basal ganglia and centrum semiovale posterior cerebral circulation: thalamus and pons) and MRI signs of concomitant CSVD. In a further step, clinical data, including detailed diagnostic workup and vascular risk factors, were analyzed with regard to RSSI features. RESULTS: Among 335 RSSI patients (mean age 71.1 ± 12.1 years), 131 (39%) RSSIs were >15 mm in axial diameter and 66 (20%) were tubular shaped. Atrial fibrillation (AF) was present in 44 (13.1%) and an ipsilateral vessel stenosis > 50% in 30 (9%) patients. Arterial hypertension and CSVD MRI markers were more frequent in patients with anterior-circulation RSSIs, whereas diabetes was more prevalent in posterior-circulation RSSIs. Larger RSSIs occurred more frequently in the basal ganglia and pons, and the latter were associated with signs of large-artery atherosclerosis. Patients with concomitant AF had no specific MRI profile. CONCLUSION: Our findings suggest the contribution of different pathophysiological mechanisms to the occurrence of RSSIs in the anterior and posterior cerebral circulation. While there appears to be some general association of larger infarcts in the pons with large-artery disease, we found no pattern suggestive of AF in RSSIs.

Longitudinal MRI dynamics of recent small subcortical infarcts and possible predictors.

We aimed to explore the morphological evolution of recent small subcortical infarcts (RSSIs) over 15 months. Moreover, we hypothesized that quantitative lesion apparent diffusion coefficient (ADC) values and serum neurofilament light (NfL) levels predict subsequent lacunar cavitation. We prospectively studied 78 RSSI patients, who underwent pre-defined follow-up investigations three and 15 months poststroke using 3 T MRI including high-resolution T1 sequences. To identify potential predictors of cavitation, we determined RSSI size and quantitative ADC values, and serum NfL using the SIMOA technique. The majority of RSSIs showed cavitation at three months (n = 61, 78%) with only minimal changes regarding cavitation status thereafter. The maximum axial lacunar diameter decreased from 8 mm at three to 7 mm at 15 months (p < 0.05). RSSIs which cavitated had lower lesional ADC values and were associated with higher baseline NfL levels compared to those without cavitation, but did not differ regarding lesion size. In logistic regression analysis, only baseline NfL levels predicted cavitation (p = 0.017). In this prospective study using predefined high-resolution MRI protocols, the majority of RSSIs evolved into lacunes during the first three months poststroke with not much change thereafter. Serum NfL seems to be a promising biomarker for more advanced subsequent tissue destruction in RSSIs.

Abnormal Blood Flow on Transcranial Duplex Sonography Predicts Poor Outcome After Stroke Thrombectomy.

Background and Purpose- Hemodynamic changes following mechanical thrombectomy for large vessel occlusion stroke could be associated with complications and might affect prognosis. We investigated postinterventional middle cerebral artery blood flow on transcranial duplex sonography (TCD) and its prognostic value for anterior large vessel occlusion stroke patients. Methods- We identified all ischemic stroke patients who had undergone mechanical thrombectomy for anterior circulation large vessel occlusion from 2010 onwards. Postinterventional middle cerebral artery flow was graded according to the sonographic Thrombolysis in Brain Ischemia score and related to patient outcome stratified by the angiographic Thrombolysis in Cerebral Infarction reperfusion status. Results- Of 215 large vessel occlusion stroke patients, 193 patients (90%) showed successful angiographic recanalization (Thrombolysis in Cerebral Infarction grade 2b-3). Of those, 69 (36%) patients had abnormal sonographic middle cerebral artery blood flow (Thrombolysis in Brain Ischemia grade 0-4) within 72 hours after mechanical thrombectomy, which was an independent predictor for poor 90-day outcome. Conclusions- TCD indicates abnormal middle cerebral artery hemodynamics in a substantial proportion of patients with angiographically defined successful mechanical thrombectomy of the anterior cerebral circulation. Such changes are associated with poor short-term outcome.

Repeated Endovascular Treatment of Early Recurrent Proximal Middle Cerebral Artery Occlusion: Case Report and Brief Review of the Literature.

Mechanical thrombectomy (MT) is the gold standard treatment for large vessel occlusion (LVO) stroke of the anterior circulation. Whether MT can also be effectively and safely performed in early recurrent LVO is largely unclear. We present the case of a middle-aged patient who was successfully treated by MT for right proximal middle cerebral artery (MCA) occlusion with excellent outcome. One day after discharge (9 days after the first MT), the patient was readmitted with wake-up stroke. MRI again revealed right proximal MCA occlusion with severe diffusion-perfusion mismatch. Repeat MT was performed and once more led to almost full recovery. The recurrent strokes were attributed to ulcerated non-stenosing plaques in the ipsilateral internal carotid artery, which prompted thromboendarterectomy. In an 18-months follow-up period, no further vascular events occurred. In conclusion, repeated MT for early recurrent LVO appears feasible in carefully selected patients. The collection of similar cases via registries would be desirable.

Dysphagia in supratentorial recent small subcortical infarcts results from bilateral pyramidal tract damage.

Background Dysphagia occurs in up to 20% of patients with a recent small subcortical infarct, even when excluding brainstem infarcts. Aim To examine the impact of lesion topography and concomitant cerebrovascular lesions on the occurrence of dysphagia in patients with a single supratentorial recent small subcortical infarct. Methods We retrospectively identified all inpatients with magnetic resonance imaging-confirmed supratentorial recent small subcortical infarcts over a five-year period. Dysphagia was determined by speech-language therapists. Recent small subcortical infarcts were compiled into a standard brain model and compared using lesion probability maps. Furthermore, magnetic resonance imaging scans were reviewed for the combination of both acute and old cerebrovascular lesions. Results A total of 243 patients with a recent small subcortical infarct were identified (mean age 67.9 ± 12.2 years). Of those, 29 had mild and 18 moderate-to-severe dysphagia. Lesion probability maps suggested no recent small subcortical infarct location favoring the occurrence of moderate-to-severe dysphagia. However, patients with moderate-to-severe dysphagia more frequently showed combined damage to both pyramidal tracts by the recent small subcortical infarct and a contralateral old lesion (lacune: 77.8% vs. 19.9%, p < 0.001; lacune or confluent white matter hyperintensities: 100% vs. 57.7%, p < 0.001) than patients without swallowing dysfunction. Comparable results were obtained when analyzing patients with any degree of dysphagia. Conclusions Preexisting contralateral vascular pyramidal tract lesions are closely related to the occurrence of moderate-to-severe dysphagia in patients with supratentorial recent small subcortical infarcts.

Serum neurofilament light is sensitive to active cerebral small vessel disease.

OBJECTIVE: To explore whether serum neurofilament light chain protein (NfL) levels are increased in patients with MRI-confirmed recent small subcortical infarcts (RSSI) compared to healthy controls and to determine the subsequent course and determinants of NfL levels in a longitudinal manner. METHODS: In a prospectively collected group of symptomatic patients with an RSSI (n = 79, mean age 61 ± 11 years, 67% male), we analyzed brain MRI and serum NfL using a Single Molecule Array (Simoa) assay at baseline and at 3 and 15 months after stroke. Community-dwelling healthy age- and sex-matched individuals with comparable severity of MRI white matter hyperintensities (WMH) (n = 53) served as controls. RESULTS: Patients with an RSSI had higher NfL baseline levels compared to controls (73.45 vs 34.59 pg/mL, p < 0.0001), and they were increasingly higher with the time from stroke symptom onset to blood sampling (median 4 days, range 1-11 days, rs = 0.51, p < 0.0001). NfL levels remained increased at the 3-month follow-up but returned to normal at 15 months after stroke. NfL levels were associated with RSSI size and baseline WMH severity and were especially high in patients with new, clinically silent cerebral small vessel disease (CSVD)-related lesions at follow-up. CONCLUSIONS: Serum NfL is increased in patients with an RSSI and the occurrence of new CSVD-related MRI lesions, even when clinically silent. This suggests NfL as a blood biomarker for active CSVD.

Early Dysphagia Screening by Trained Nurses Reduces Pneumonia Rate in Stroke Patients: A Clinical Intervention Study.

BACKGROUND AND PURPOSE: Dysphagia is a common stroke symptom and leads to serious complications such as aspiration and pneumonia. Early dysphagia screening can reduce these complications. In many hospitals, dysphagia screening is performed by speech-language therapists who are often not available on weekends/holidays, which results in delayed dysphagia assessment. METHODS: We trained the nurses of our neurological department to perform formal dysphagia screening in every acute stroke patient by using the Gugging Swallowing Screen. The impact of a 24/7 dysphagia screening (intervention) over swallowing assessment by speech-language therapists during regular working hours only was compared in two 5-month periods with time to dysphagia screening, pneumonia rate, and length of hospitalization as outcome variables. RESULTS: Overall, 384 patients (mean age, 72.3±13.7 years; median National Institutes of Health Stroke Scale score of 3) were included in the study. Both groups (pre-intervention, n=198 versus post-intervention, n=186) were comparable regarding age, sex, and stroke severity. Time to dysphagia screening was significantly reduced in the intervention group (median, 7 hours; range, 1-69 hours) compared with the control group (median, 20 hours; range, 1-183; P=0.001). Patients in the intervention group had a lower rate of pneumonia (3.8% versus 11.6%; P=0.004) and also a reduced length of hospital stay (median, 8 days; range, 2-40 versus median, 9 days; range, 1-61 days; P=0.033). CONCLUSIONS: 24/7 dysphagia screening can be effectively performed by nurses and leads to reduced pneumonia rates. Therefore, empowering nurses to do a formal bedside screening for swallowing dysfunction in stroke patients timely after admission is warranted whenever speech-language therapists are not available.

Frequency and Predictors of Dysphagia in Patients With Recent Small Subcortical Infarcts.

BACKGROUND AND PURPOSE: Detailed data on the occurrence of swallowing dysfunction in patients with recent small subcortical infarcts (RSSI) in the context of cerebral small vessel disease are lacking. This prompted us to assess the frequency of and risk factors for dysphagia in RSSI patients. METHODS: We identified all inpatients with magnetic resonance imaging-confirmed RSSI between January 2008 and February 2013. Demographic and clinical data were extracted from our stroke database, and magnetic resonance imaging scans were reviewed for morphological changes. Dysphagia was determined according to the Gugging Swallowing Screen. RESULTS: We identified 332 patients with RSSI (mean age, 67.7±11.9 years; 64.5% male). Overall, 83 patients (25%) had dysphagia, which was mild in 46 (55.4%), moderate in 26 (31.3%), and severe in 11 patients (13.3%). The rate of dysphagia in patients with supratentorial RSSI was 20%. Multivariate analysis identified a higher National Institutes of Health Stroke Scale score (P<0.001), pontine infarction (P<0.01), and more severe white matter hyperintensities (Fazekas grades 2 and 3, P=0.03) as risk factors for swallowing dysfunction. CONCLUSIONS: Dysphagia is present in a quarter of patients with RSSI and has to be expected especially in those with higher stroke severity, pontine infarction, and severe white matter hyperintensities.