Clinical analysis of different parts of medullary infarction / 中华神经科杂志

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.

Lateral medullary infarction resembling myelopathy :a case report and literature review / 中国脑血管病杂志

The incidence of lateral medullary infarction is higher in clinical practice,which is mainly manifested as crossed sensory dysfunction .while the lateral medullary infarction with segmental development of sensory level is rare and easily confused with myelopathy. In this paper,we report the clinical data of a patient with lateral medullary infarction resembling myelopathy,and analyzes the classification,infarct site, responsible vessel,etiology,treatment and prognosis of lateral medullary infarction with sensory dysfunction level in combination with previous literature,so as to provide reference for the diagnosis and treatment of similar cases.

Neural Correlates of Urinary Retention in Lateral Medullary Infarction / 대한배뇨장애요실금학회지

PURPOSE: The brainstem plays an important role in the control of micturition, and brainstem strokes are known to present with micturition dysfunction. Micturition dysfunction in cases of lateral medullary infarction (LMI) is uncommon, but often manifests as urinary retention. In this study, we investigated the neuro-anatomical correlates of urinary retention in patients with LMI. METHODS: This was a hospital-based retrospective study conducted in the neurology unit of a quaternary-level teaching hospital. Inpatient records from January 2008 to May 2018 were searched using a computerized database. Cases of isolated LMI were identified and those with micturition dysfunction were reviewed. MRI brain images of all patients were viewed, and individual lesions were mapped onto the Montreal Neurological Institute (MNI) space manually using MRIcron. Nonparametric mapping toolbox software was used for voxel-based lesion-symptom analysis. The Liebermeister test was used for statistical analysis, and the resultant statistical map was displayed on the MNI template using MRIcron. RESULTS: During the study period, 31 patients with isolated LMI were identified. Their mean age was 48 years and 28 (90%) were male. Six of these patients (19%) developed micturition dysfunction. All 6 patients had urinary retention and 1 patient each had urge incontinence and overflow incontinence. In patients with LMI, the lateral tegmentum of the medulla showed a significant association with urinary retention. CONCLUSIONS: In patients with isolated LMI, we postulate that disruption of the descending pathway from the pontine micturition centre to the sacral spinal cord at the level of the lateral tegmentum results in urinary retention.

Dysphagia May Be an Independent Marker of Poor Outcome in Acute Lateral Medullary Infarction

BACKGROUND AND PURPOSE: The functional recovery after the lateral medullary infarction (LMI) is usually good. Little is known about the prognostic factors associated with poor outcome following acute LMI. The aim of this study was to identify the factors associated with poor long-term outcome after acute LMI, based on experiences at a single center over 11 years. METHODS: A consecutive series of 157 patients with acute LMI who were admitted within 7 days after symptom onset was evaluated retrospectively. Clinical symptoms were assessed within 1 day after admission, and outcomes were evaluated over a 1-year period after the initial event. The lesions were classified into three vertical types (rostral, middle, and caudal), and the patients were divided into two groups according to the outcome at 1 year: favorable [modified Rankin Scale (mRS) score or =2). RESULTS: Of the 157 patients, 93 (59.2%) had a favorable outcome. Older age, hypertension, dysphagia, requirement for intensive care, and pneumonia were significantly more prevalent in the unfavorable outcome group. The frequencies of intensive care (13%) and mortality (16.7%) were significantly higher in the rostral lesion (p=0.002 and p=0.002). Conditional logistic regression analysis revealed that older age and initial dysphagia were independently related to an unfavorable outcome at 1 year [odds ratio (OR)=1.04, 95% confidence interval (95% CI)=1.001-1.087, p=0.049; OR=2.46, 95% CI=1.04-5.84, p=0.041]. CONCLUSIONS: These results suggest that older age and initial dysphagia in the acute phase are independent risk factors for poor long-term prognosis after acute LMI.

Isolated Axial Lateropulsion in Lateral Medullary Infarction

The Wallenberg's syndrome is produced by infarction of lateral medulla. Isolated ipsilateral axial lateropulsion without other common symptoms of Wallenberg syndrome has rarely been reported as manifestation of lateral medullary infarction. The responsible anatomical structure of ipsilateral axial lateropulsion is still uncertain. We describe a patient with lateral medullary infarction who present with isolated ipsilateral axial lateropulsion without other symptoms of Wallenberg syndrome.

Lateral Medullary Infarction with Ipsilesional Gaze-Evoked and Head-Shaking Nystagmus / 대한평형의학회지

For differential diagnosis between vestibular neuritis and lateral medullary infarction with similar clinical features, bedside examination of nystagmus is important. We report a 45-year-old male who presented with acute vertigo for two days. He showed spontaneous right-beating nystagmus. However, left-beating nystagmus was evoked during bilateral horizontal gaze and by horizontal head oscillation. Brain MRI revealed an acute infarction in the left lateral medulla.

High-Resolution Contrast-Enhanced 3D-Spoiled Gradient-Recalled Imaging for Evaluation of Intracranial Vertebral Artery and Posterior Inferior Cerebellar Artery in Lateral Medullary Infarction

PURPOSE: To determine whether high-resolution contrast-enhanced three dimensional imaging with spoiled gradient-recalled sequence (HR-CE 3D-SPGR) plays a meaningful role in the assessment of intracranial vertebral artery (ICVA) and posterior inferior cerebellar artery (PICA) in lateral medullary infarction (LMI). MATERIALS AND METHODS: Twenty-five patients confirmed with LMI were retrospectively enrolled with approval by the IRB of our institute, and 3T MRI with HR-CE 3D-SPGR and contrast-enhanced magnetic resonance angiography (CE-MRA) were performed. Two radiologists who were blinded to clinical information and other brain MR images including diffusion weighted image independently evaluated arterial lesions in ICVA and PICA. The demographic characteristics, the area of LMI and cerebellar involvement were analyzed and compared between patients with arterial lesion in ICVA only and patients with arterial lesions in both ICVA and PICA on HR-CE 3D-SPGR. RESULTS: Twenty-two of twenty-five LMI patients had arterial lesions in ICVA or PICA on HR-CE 3D SPGR. However twelve arterial lesions in PICA were not shown on CE-MRA. Concurrent cerebellar involvement appeared more in LMI patients with arterial lesion in ICVA and PICA than those with arterial lesion in ICVA alone (p = 0.069). CONCLUSION: HR-CE 3D-SPGR can help evaluate arterial lesions in ICVA and PICA for LMI patients.

Isolated Body Lateropulsion as a Presenting Symptom of Lateral Medullary Infarction / 대한평형의학회지

Body lateropulsion is a common manifestation of lateral medullary infarction (LMI), and usually associated with vertigo, limb ataxia, sensory disturbance, and Horner's syndrome. However, isolated body lateropulsion as a presenting symptom of LMI is rare, and the responsible lesion for lateropulsion remains uncertain. We report a 71-year-old woman who showed isolated body lateropulsion as a presenting symptom of LMI. Ipsilateral body lateropulsion in our patient may be ascribed to the involvement of the ascending dorsal spinocerebellar tract rather than the descending lateral vestibulospinal tract, which runs more ventromedially.

A Case of Lateral Medullary Infarction after Endovascular Trapping of the Vertebral Artery Dissecting Aneurysm

We report an unusual case of lateral medullary infarction after successful embolization of the vertebral artery dissecting aneurysm (VADA). A 49-year-old man who had no noteworthy previous medical history was admitted to our hospital with a severe headache. Computed tomography (CT) revealed a subarachnoid hemorrhage, located in the basal cistern and posterior fossa. Cerebral angiography showed a VADA, that did not involve the origin of the posterior inferior cerebellar artery (PICA). We treated this aneurysm via endovascular trapping of the vertebral artery distal to the PICA. After operation, CT revealed post-hemorrhagic hydrocephalus, which we resolved with a permanent ventriculoperitoneal shunt procedure. Postoperatively, the patient experienced transient mild hoarsness and dysphagia. Magnetic resonance image (MRI) showed a small infarction in the right side of the medulla. The patient recovered well, though he still had some residual symptom of dysphagia at discharge. Such an event is uncommon but can be a major clinical concern. Further investigation to reveal risk factors and/or causative mechanisms for the medullary infarction after successful endovascular trapping of the VADA are sorely needed, to minimize such a complication.

A Case of Ipsilateral Hemiparesis in Lateral Medullary Infarction: As a Warning Sign of Acute Progression of Vertebral Artery Thrombosis / 대한뇌졸중학회지

A 70-year-old man presented with acute dysarthria and dizziness. He denied any history of trauma or cervical manipulations within several weeks before symptom onset. We could make a presumptive diagnosis of left Wallenberg syndrome through the results of neurologic examination, which include left limb ataxia, alternating hyp(o)esthesia, spontaneous nystagmus to right side, and left side Honer's syndrome. Initial diffusion weighted imaging performed at admission showed small and discrete high signal lesions in left lateral medulla, left cerebellar hemisphere, and bilateral occipital areas. Contrast enhanced MRA demonstrated a filling defect in long segment of distal left vertebral artery. On 4th days after symptom onset, the patient developed a severe form of ipsilateral hemiparesis. Follow-up brain MRI showed a downward extension of the initial ischemic lesion in upper medulla to upper cervical region. This case suggests that a severe form of ipsilateral hemiparesis may be complicated in the clinical setting of acute lateral medullary infarction with vertebral artery occlusion.

Isolated Dysphagia Caused by Failure of Cricopharyngeal Muscle Relaxation after Left Lateral Medullary Lacunar Infarction: A case report

Dysphagia can be caused by various mechanisms such as impaired tongue movement, delayed swallowing reflex, decreased pharyngeal peristalsis, incomplete closure of epiglottis and cricopharyngeal dysfunction. Cricopharyngeal muscle, forming the upper esophageal sphincter, acts as a muscular sling between the pharynx and the esophagus. Normally, it closes constantly at rest and opens during laryngeal elevation through active relaxation on the one hand and passive traction by the antero-cephalad laryngeal movement on the other. If its incoordination or hypertonicity happens, dysphagia can develop. Cricopharyngeal muscle dysfunction is caused by various situations such as neuromuscular diseases, postoperative changes and stroke, particularly after brainstem stroke. We report a case of isolated dysphagia caused by failure of active relaxation of cricopharyngeal muscle without aspiration after left lateral medullary lacunar infarction.

Pure Limb Ataxia as Isolated Manifestation in Lateral Medullary Infarction

Pure limb ataxia without other common symptoms of Wallenberg syndrome has rarely been reported as manifestation of lateral medullary infarction. We describe a patient with lateral medullary infarction who presented with almost isolated right limb(mainly lower limb) ataxia without usual symptoms such as hemibody sensory changes, dysphagia, hoarseness, hiccup, and Horner sign. The brain magnetic resonance image showed small ischemic lesion involving the dorsolateral portion of the medulla oblongata.

A Case Of Lateral Medullary Infarction Presenting as Isolated Dysphagia with Unilateral Vocal Fold Paralysis / 대한이비인후과학회지

Unilateral vocal cord paralysis and dysphagia are not uncommonly seen in the ENT practice. Just less than 10% of unilateral vocal cord paralysis are caused by diseases of the central nervous system, and lateral medullary infarction (LMI) is a wellknown condition that causes dysphagia and unilateral laryngeal paralysis. However, cases of LMI with isolated dysphagia and dysphonia without other typical neurological signs have been rarely reported. We describe the case of a 67-year-old man with chronic hypertension who presented as dysphagia and unilateral vocal cord paralysis without other typical signs of LMI. He was finally diagnosed as LMI on MRI. Although cases of LMI presenting in the manner like this case are extremely rare, ENT physicians should consider LMI in differential diagnosis for this situation, especially when the patient has a previous episode or risk factors of stroke.

Pure Sensory Deficit at the T4 Sensory Level as an Isolated Manifestation of Lateral Medullary Infarction

In rare cases restricted sensory deficits along the somatotopic topography of the spinothalamic tract can develop from a lateral medullary infarction. To our knowledge, isolated dermatomal sensory deficit as a single manifestation of a lateral medullary infarction has not been reported previously. A 58-year-old man presenting with sudden left-sided paresthesia complained of sensory deficit of pain and temperature below the left T4 sensory level without other neurologic deficits. Diffuse- and T2-weighted magnetic resonance imaging (MRI) of the brain showed high signal intensities in the right lower medulla oblongata, whereas thoracic-spine MRI and somatosensory evoked potentials produced normal findings.

A Case of Ocular Flutter after Right Posterolateral Medullary Infarction

No abstract available.

Diffusion Weighted Imaging Findings in the Acute Lateral Medullary Infarction

BACKGROUND AND PURPOSE: Negative findings on diffusion-weighted imaging (DWI) does not exclude the possibility of brainstem infarction, particularly in the acute stage of medullary lesion. Our aim was to investigate the false-negative rate of DWI in patients with acute lateral medullary infarction. METHODS: We applied DWI to 26 patients with a clinical diagnosis of lateral medullary infarction within 72 h of the onset. We assessed relationships between initial DWI findings and time-to-MRI (the time between onset of symptoms and initial DWI), number of clinical symptoms and signs, and final lesion volume. RESULTS: There were 8 cases (31%) of false negatives in the initial DWI results. The occurrence of false-negative DWI findings decreased significantly as the time-to-MRI increased (P=0.014). However, the false-negative rate was not significantly correlated with the number of clinical symptoms and signs or the final lesion volume. CONCLUSIONS: The diagnosis of lateral medullary infarction should not be ruled out on the basis of early negative DWI. To confirm the lesion, follow-up DWI or further MRI should be performed in cases with early negative DWI results

A Case of Lateral Medullary Infraction Presenting with Thoracic Sensory Level

Loss of pain and temperature sensation due to lateral medullary infarction are well known and classically involve the ipsilateral side of the face and the lower part of the body on the controlateral side. This pattern of sensory loss below a certain level on the trunk, usually a sign of spinal cord disease, may also appear following a lesion in the lateral medullar, due to damage to the spinothalamic tract. A 72-year-old hypertensive man developed sudden dizziness, headache, and gait ataxia. On neurologic examination, he had left limb and gait ataxia. Five days later he noted loss of pain and temperature sensation on the right leg and trunk with a sensory level at T4 with preservation of touch, vibration, and joint position sense in all limbs. Brain MRI showed a small infarct in the left lower lateral medulla. Brain MR angiography showed stenosis of the right proximal carotid artery, left distal vertebral artery, and mid-basilar artery. We report a case of sensory defects with a sensory level on the trunk that occured as the result of lesion of the lower lateral medulla.