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Objective:To investigate the clinical, imaging, etiological and prognostic features of patients with infarctions in different locations of the medulla oblongata.Methods:Patients with acute medullary infarction hospitalized at Tianjin Huanhu Hospital from July 2017 to July 2022 were included. The risk factors, clinical manifestation, stroke mechanism and 90-day prognosis of these patients were analyzed retrospectively.Results:Among the 256 patients enrolled, 150 (58.6%) had lateral medullary infarction (LMI), 106 (41.4%) had medial medullary infarction (MMI). The most frequent clinical manifestation of patients with LMI was dizziness (84.7%,127/150). And motor disorders (83.0%,88/106) was the most frequent clinical manifestation of patients with MMI. LMI lesions were mostly located in the middle (42.7%,64/150) and MMI lesions were mostly located in the upper (60.4%,64/106) medulla oblongata, with statistically significant difference (χ 2=47.53, P<0.001). Large artery atherosclerosis (LAA) was the main stroke mechanism in LMI and MMI [57.3%(86/150) vs 56.6%(60/106)]. Early neurological deterioration was more common in MMI (25.5%,27/106) and less common in LMI (7.3%,11/150), with statistically significant difference (χ 2=16.17, P<0.001). At discharge, more patients with MMI showed poor prognosis in short term [45.3% (48/106) vs 24.0% (36/150), with statistically significant difference (χ 2=12.76, P<0.001)] and even long term at 90-day follow-up [33.0% (35/106) vs 12.7% (19/150), also with statistically significant difference (χ 2=15.48, P<0.001)] than those with LMI. A total of 10 patients (4.0%, 10/256) developed respiratory failure during hospitalization, including 7 patients with LMI (4.7%, 7/150) and 3 patients with bilateral MMI (2.8%,3/106). Early neurological deterioration ( OR=3.38, 95% CI 1.25-9.10, P=0.016) and LAA (compared with small artery occlusion) ( OR=3.08, 95% CI 1.13-8.37, P=0.028) were independent risk factors for poor prognosis in MMI. Age ( OR=1.01, 95% CI 1.01-1.17, P=0.026) and early neurological deterioration ( OR=20.19, 95% CI=2.63-155.06, P=0.004) were independently correlated with poor outcome in LMI. Conclusions:LMI and MMI had similar etiology and significant differences in clinical manifestations, early neurological deterioration and prognosis. Further classification of medullary infarction was of great significance for diagnosis, treatment and prognosis evaluation.
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Objective To investigate the clinical features of bilateral medial medullary infarction (BMMI)in elderly patients.Methods Clinical and imaging data of 8 elderly BMMI patients with different morphology on diffusion-weighted magnetic resonance imaging (DWI-MR) were retrospectively analyzed.All patients were diagnosed by MRI,while 4 patients received CTA and vascular ultrasound testing,and the other 4 patients received vascular ultrasound testing.Results All 8 cases(100.0％) had acute-onset BMMI.Patients showed varying degrees of acroparalysis(7/8,87.5 ％),dizziness (5/8,62.5 ％),dysarthria(6/8,80.0 ％),dysphagia(3/8,37.5 ％),deep or superficial sensory dysfunction(5/8,62.5 ％),consciousness disorders (2/8,25.0 ％),dyspnea (2/8,25.0 ％),and tinnitus(1/8,12.5 ％).Lesions in most patients were located in the upper part of medulla oblongata(7/8,87.5 ％).In the transverse direction of DWI,the lesions as the inverted V shape were seen in 3 cases (37.5％),the V shape(12.5％)in 1 case,the Y shape(37.5％)in 3 cases,and the heart shape(12.5％) in 1 case.All 8 patients were complicated with posterior cerebral artery stenosis or occlusion,of whom patients with heart-or Y-shaped lesions showed progressive exacerbation.After treatment,4 cases (50.0 ％) recovered,3 cases (37.5 ％) improved,and 1 case (12.5 ％) unrecovered before discharge from the hospital.Conclusions Most elderly BMMI patients have concurrent posterior circulation artery stenosis,and patients with heart-or Y-shaped lesions on MR-DWI show rapid progression and have a poor prognosis.Cranial examination with MR-DWI is helpful for early clinical diagnosis of BMMI,prediction of disease progression and effective prevention of complications.
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Objective: To investigate the clinical characteristics of medial medullary infarction (MMI) and their relationship with vascular lesions. Methods: Eighteen patients with clinical symptoms of MMI and confirmed by magnetic resonance imaging (MRI) were selected. Among them, 10 were performed head CTA examination, and 4 were performed cerebral panangiography. The clinical and imaging findings and the outcomes were observed. Results: Circled digit oneAmong the 18 patients, the lesions in 6 patients only affected the medial-ventral part of medulla (mainly causing contralateral limb movement disorder), in 2 patients affected the central part of medulla oblongata (mainly causing sensory dysfunction), and in 4 patients affected the dorsal side of medulla oblongata (mainly causing nystagmus and dizziness). The whole medial medulla were injured in the remaining 6 patients. Circled digit twoThe lesions were detected in 15 patients on T1WI, T2WI, and DWI sequences. The lesions were only detected in 2 patients on T2WI sequence. One patient showed equal signal on T1WI, T2WI, and a lesion was detected on T2WI one week after MRI reexamination. Circled digit threeAmong the 18 patents with MMI, 8 were complicated with diabetes. Six of them performed CTA/DSA examinations, and no vertebral artery lesions were detected. Ten patients were not complicated with diabetes (all with hypertension and elevated low-density lipoprotein), and 8 of them performed CTA/DSA examinations, and the vertebral artery lesions were detected in 7 patients. Conclusions: MMI mainly damages the ventral part of medulla oblongata. MRI is a preferred method at present in the diagnosis of medullary infarction. Diabetes causes small vascular disease and vertebral artery disease may participate the pathogenic process of MMI.
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BACKGROUND: The medial vestibulospinal tract (MVST), which descends in the medial longitudinal fasciculus (MLF), may mediate the vestibular evoked myogenic potentials (VEMPs) in the contracting sternocleidomastoid muscle. We report herein abnormal VEMPs in a patient with medial medullary infarction (MMI) that appeared to involve the MLF. CASE REPORT: A patient with infarction involving the right medial medulla showed decreased p13-n23 amplitude and increased p13/n23 latencies of the VEMPs on the right side. These abnormal VEMPs recorded in an MMI patient support the theory that VEMPs are mediated by the MVST contained within the MLF. CONCLUSIONS: VEMPs may represent a valuable tool for investigating vestibular dysfunction originating from the saccule, even in patients with central vestibulopathies, which is not readily defined by conventional vestibular function tests.