Striatocapsular Infarction Research Articles

Striatocapsular infarction and acquired stuttering

Striatocapsular infarction may result in a multitude of language and speech disturbances. Acquired stuttering is a rare speech disorder that occurs as an aftermath of this stroke syndrome. We report on the case of 6o-year-old right-handed woman who presented with acute right-sided hemiparesis and stuttering. Language assessment revealed intact comprehension, naming, reading and writing. When the patient spoke spontaneously, there were frequent initial prolongations with repetition of initial syllables. There was no word-finding difficulty or paraphasia. Her stuttering improved remarkably after few weeks but persistent in a very mild degree. Acute striatocapsular infarction-induced acquired stuttering is rare. It may be a transient event and generally holds a good prognosis. It can occur without subcortical aphasia or dysarthria.

Shadow sign in a T2* brain image in spontaneous middle cerebral artery dissection

A 29-year-old man presented with unilateral dull headache for 3 days, similar to previous headache, but with right hemiparesis; there was no antecedent infection or trauma. MRI showed left striatocapsular infarction (figure 1A), without evidence of cardioembolism or vasculitis. Digital subtraction angiography demonstrated stenosis of the left middle cerebral artery (MCA) trunk (figure 1B). Intramural hematoma suggests arterial dissection.1 The bulging intramural hematoma seen on T2* corresponded with an eccentric high signal rim on sagittal T1-weighted imaging, along the anterosuperior MCA wall at the arterial perforator origin (figure 2). The diagnosis was spontaneous MCA dissection.

Neuropsychiatric Symptoms as a Putative Crescendo Warning of a Striatocapsular Infarct?

Neuropsychiatric Symptoms as a Putative Crescendo Warning of a Striatocapsular Infarct?

Striatocapsular Infarction; a Single Institutional Experience

Objective:Striatocapsular infarction is an uncommon form of deep hemispheric strokes. We analyzed the clinical presentation of this stroke to determine its core features and neurological outcome.Material and methods:This prospective, observational, short-term longitudinal study was carried out from November 1, 2009 to October 30, 2011 in the department of neurology, Sulaimaniya general teaching hospital, Iraq and involved 13 consecutive Kurdish patients who were diagnosed with striatocapsular infarction radiologically; all patients underwent routine blood tests, resting 12-lead ECG, transthoracic echocardiography, and urgent non-contrast CT brain scanning at the time of admission. All patients were reassessed clinically after 3 months.Results:Nine patients (69%) were females and 7 patients (53%) were older than 50 years of age. Infarction of the right lenticular nucleus was more common than the left one. Severe flaccid hemiplegia dominated the clinical presentation. Speech and language dysfunction were found in 4 patients (30%) while inattention and neglect were detected in 8 patients (61%). At 3 months, 4 patients were bed-ridden and 4 were wheel-chair bound; dystonia and involuntary movements did not occur. Only the patient with bilateral infarction demonstrated Parkinsonism.Conclusion:Striatocapsular infraction in Iraqi Kurdish patients was more common in females and at the right lenticular nucleus. Hypertension, smoking, and hypercholesterolemia were the commonest risk factors. Dense hemiplegia was the commonest presentation; the functional outcome was poor in the majority. After 3 months of the ischemic event, involuntary movements and dystonia were not seen, and Parkinsonism was found in one patient only.

Disappearing Hyperdense Middle Cerebral Artery Sign Is Associated with Striatocapsular Infarcts on Follow-Up CT in Ischemic Stroke Patients Treated with Intravenous Thrombolysis

Background: A striatocapsular infarct (SCI) is a subcortical infarct in the territory of the lenticulostriate arteries, most likely due to transient occlusion of the main stem of the middle cerebral artery (MCA). Presence of the hyperdense middle cerebral artery sign (HMCAS) is a reliable marker of occlusion of the MCA. We hypothesized that SCIs are related to HMCAS at baseline, which subsequently disappears (HMCAS-D) on follow-up CT in stroke patients treated with intravenous rtPA. Methods: Baseline and 24-hour follow-up CTs were evaluated for HMCAS in acute ischemic stroke patients treated with intravenous rtPA and follow-up scans were also reviewed for the presence of isolated cortical (CIn), SCI, cortical and striatocapsular (CI-SCI) or lacunar infarct. We determined the incidence of SCI and the association between SCI and HMCAS on baseline and follow-up CT. Results: Of the 247 patients, 43 had an SCI (17.4%; 95% CI: 13.1–22.5). The presence of HMCAS at baseline was related to the occurrence of infarction with involvement of the striatocapsular region (SCI or CI-SCI) on follow-up CT (OR: 11.6; 95% CI: 5.9–22.8). HMCAS-D on follow-up scans was significantly related to SCI on follow-up CT compared to CI-SCI (OR: 4.9; 95% CI: 3.7–6.1). Conclusions: Occurrence of SCI and CI-SCI is associated with the presence of HMCAS on CT before thrombolysis, whereas HMCAS-D on follow-up CT is strongly related to the occurrence of SCI. Our findings support the causative role of transient occlusion of the MCA main stem in the pathogenesis of SCI.

The role of the unaffected hemisphere in motor recovery after stroke

The contribution of the ipsilateral (nonaffected) hemisphere to recovery of motor function after stroke is controversial. Under the assumption that functionally relevant areas within the ipsilateral motor system should be tightly coupled to the demand we used fMRI and acoustically paced movements of the right index finger at six different frequencies to define the role of these regions for recovery after stroke. Eight well-recovered patients with a chronic striatocapsular infarction of the left hemisphere were compared with eight age-matched participants. As expected the hemodynamic response increased linearly with the frequency of the finger movements at the level of the left supplementary motor cortex (SMA) and the left primary sensorimotor cortex (SMC) in both groups. In contrast, a linear increase of the hemodynamic response with higher tapping frequencies in the right premotor cortex (PMC) and the right SMC was only seen in the patient group. These results support the model of an enhanced bihemispheric recruitment of preexisting motor representations in patients after subcortical stroke. Since all patients had excellent motor recovery contralesional SMC activation appears to be efficient and resembles the widespread, bilateral activation observed in healthy participants performing complex movements, instead of reflecting maladaptive plasticity.

Striatocapsular infarction associated with middle cerebral artery disease

【背景および目的】線条体内包梗塞(striatocapsular infarction：SCI)は，多くは塞栓機序によるが，中大脳動脈アテローム血栓性梗塞(MCA-ATBI)としてのSCIの系統的な報告はみられない．今回，MCA-ATBIとSCIについて，その臨床的特徴，梗塞メカニズムに対する考察を行った．【対象と方法】連続症例よりMCAアテローム血栓性病変が閉塞または50%以上の狭窄を示す56症例を選出し，梗塞病型によりSCI単独例のpure SCI：10例，SCIに他の梗塞を伴うSCI plus：5例，SCI以外の梗塞non-SCI：41例に分類した．【結果】SCI群では，12例がMCA閉塞，3症例がMCA狭窄を示した．SCI群ではすべてMCA水平部病変であったが，non-SCI群ではMCA水平部病変は62.5%であった．SCI群ではnon-SCI群に比して，急性期進行が多い傾向にあった(p = 0.092，χ二乗検定)．退院時mRSを基準に解析すると，SCI群はnon-SCI群に比較して重症の傾向にあった(p = 0.0504，Mann-WhitneyのU検定)．【結論】MCAアテローム血栓性病変に伴うSCIの機序として，MCA水平部の閉塞・高度狭窄，さらに，MCA水平部アテロームプラークによる複数のレンズ核線条体動脈の閉塞が考えられた．急性期MCA-ATBIにおいてSCIを示す症例では機能予後不良のものが多く，早期より積極的な治療介入が必要である．

Leg Edema With Deep Venous Thrombosis-Like Symptoms as an Unusual Complication of Occult Bladder Distension and Right May-Thurner Syndrome in a Stroke Patient: A Case Report

Im S, Lim S-H, Chun H-J, Ko Y-J, Yang B-W, Kim H-W. Leg edema with deep venous thrombosis-like symptoms as an unusual complication of occult bladder distension and right May-Thurner syndrome in a stroke patient: a case report. Overt bladder distension can compress the iliac vessels and result in lower extremity swelling mimicking deep venous thrombosis (DVT). This phenomenon has been reported in patients with bladder outlet obstruction due to prostatism but no report has been made in relation to poststroke urinary retention (UR). The authors experienced a rare case of abrupt leg edema with DVT-like symptoms due to iliac vein compression by an overdistended bladder that had developed after cerebrovascular stroke. A 74-year-old woman with left striatocapsular infarction and situs inversus presented with severe right leg swelling. Imaging studies revealed external compression of the right iliac veins by an overdistended bladder and underlying May-Thurner syndrome (MTS). The presence of situs inversus totalis resulted in the rare clinical finding of a right-sided MTS. The patient's symptoms were largely attributable to external compression of right iliac veins by bladder distension and they resolved completely after prompt bladder drainage. Follow-up imaging findings showed complete regression of right external iliac vein stenosis. This case provides the first description of lower extremity swelling manifest as an unusual complication from UR in a stroke patient. Proper and strict bladder screening with appropriate management should be implemented as important therapeutic components during the rehabilitative management of stroke patients.

急性期アテローム性中大脳動脈狭窄症例の病態

Background and purpose: Although intracranial atherosclerotic disease has been highlighted especially in Asian countries, little is known about the stroke mechanism of middle cerebral artery (MCA) stenosis. Patients with MCA stenosis often show acute neurological worsening. However, no study has ever been focused on stroke mechanism and acute neurological worsening in patients with MCA stenosis. We conducted the present study to clarify the relationship between stroke mechanism and acute neurological worsening in patients with MCA stenosis.Methods: From consecutive acute ischemic stroke patients entered in our hospital, we selected 30 patients who had MCA stenosis. Patient characteristics, clinical course and lesion patterns were correlated.Results: Acute neurological worsening was observed in 10 patients (30%), of whom 8 patients exhibited poor prognosis. Diabetes mellitus tended to be significantly associated with acute neurological worsening. Subcortical small multiple infarcts, deep border-zone infarcts and striatocapsular infarction tended to be significantly associated with acute neurological worsening.Conclusion: Two main stroke mechanisms appear to contribute to acute neurological worsening in patients with MCA stenosis. One mechanism is a combination of hypoperfusion and micro-embolism. The other mechanism is occlusion of multiple lenticulostriate arteries by MCA plaque. Clarifying mechanism may help to decide therapeutic strategies.

Thrombosis and Recanalization of Straight Sinus

We describe a case of a 14-year-old boy who presented to the emergency department with nausea, vomiting, headache, and mental status changes. Noncontrast computed tomography scan of the brain in the emergency department revealed bilateral thalamic and striatocapsular infarcts. The patient was diagnosed with possible thrombosis of the thalamostriate veins, which was confirmed with urgent magnetic resonance venography (MRV). Magnetic resonance venography revealed that the thrombosis was extended to the straight sinus and the internal cerebral veins. Thrombosis of the straight sinus in children results in a rare stroke with inconsistent clinical manifestations, depending on collateral venous circulation of the thrombosed sinus. The diagnosis is quite difficult, especially when symptoms are nonspecific and variable. Timely diagnosis, based on the decision of performing emergency magnetic resonance imaging and MRV, followed by the administration of anticoagulation therapy may reverse this condition as in our patient who made an excellent recovery.

Can We Discriminate Stroke Mechanisms by Analyzing the Infarct Patterns in the Striatocapsular Region?

Background and Aims: The aims of our study were to elucidate the differences in the distribution of acute middle cerebral artery (MCA) infarctions involving the striatocapsular region and to compare those following embolic striatocapsular infarctions with those originating from MCA disease (MCAD). Methods: We prospectively enrolled patients with acute large infarcts located in the lenticulostriate artery territory. Brain coronal diffusion-weighted imaging (DWI) and magnetic resonance angiography were carried out in all patients. The types of infarct distribution were divided into 3 categories: (1) dominant in the distal territory (DD), (2) distributed equally between the distal and proximal territories (DE) and (3) dominant in the proximal territory. Stroke mechanisms were classified into stroke from proximal embolism, MCAD and stroke of undetermined etiology. Results: A total of 71 patients were recruited. Proximal embolic sources were significantly more prevalent in patients with a DE lesion, but symptomatic MCA stenoses were more common in patients with a DD lesion than in those with a DE lesion. Conclusion: These results suggest that the dominant area of striatocapsular infarctions on coronal DWI can be an important clue for stroke etiology.

Emotional facial palsy following striato-capsular infarction

Emotional facial palsy (EFP) is a rare condition in which facial paresis is only apparent during reflex movements of the hemiface, such as smiling and laughter. We report the case...

Association of Initial Infarct Extent and Progressive Motor Deficits in Striatocapsular Infarction

Background and purposeProgression of motor deficits in the acute period is frequently observed in patients with subcortical striatocapsular infarctions. Therefore, we sought to determine the factors associated with early motor progression in patients with infarcts confined to the striatocapsular region.MethodsWe studied 80 consecutive patients with striatocapsular-region infarction, as defined by clinical and MRI criteria, within 24 hours after stroke onset. Motor progression was defined as an increase of >2 points in the motor items of the National Institutes of Health Stroke Scale (NIHSS) within 7 days of stroke onset. The study population was divided into patients with and without motor progression, and risk factors, clinical features, and brain MRI/magnetic resonance angiograpy (MRA) findings were compared between these groups.ResultsMotor progression was observed in 40% of the 80 patients. The independent variables associated with motor progression were a history of hypertension (OR=7.8, 95% CI=1.5-39.8, p=0.013) and an initial infarct extent of ≥15 mm (OR=9.2, 95% CI=1.8-45.7, p=0.006). However, there were no differences in the initial NIHSS score, other stroke risk factors, vascular stenosis pattern, or cardioembolic source.ConclusionsEarly motor progression in patients with striatocapsular-region infarction is associated with the initial extent of the lesion. However, the stroke mechanism and vascular stenosis did not differ between the motor progression and stable groups.

Presumed and confirmed striatocapsular brain infarctions in six dogs

To describe the clinical and diagnostic features of the canine sensorimotor syndrome caused by striatocapsular brain infarctions (SCI). Six dogs with diagnostic imaging or postmortem evidence of SCI. Medical records of dogs with SCI were retrospectively reviewed and the signalment, history, clinical signs, antemortem clinicopathologic test results, diagnostic imaging findings, case outcomes, and pathologic findings recorded. All dogs had an acute onset of nonprogressive homonymous visual field deficits and contralateral general proprioceptive (GP) deficits. Contralateral hemiparesis and facial hypalgesia were noted in 5/6 dogs. CT scans were normal in 2/4 dogs, and revealed poorly defined hypoattenuating lesions in the subcortical white matter in two dogs. MRI exams were performed in 5/6 dogs and revealed unilateral, variably sized, striatocapsular lesions consistent with nonhemorrhagic infarctions. Diagnostic imaging (6/6) and postmortem examinations (2/6) suggested that SCI resulted from lesions in the vascular territories of the rostral choriodal (6/6) and lenticulostriate arteries (2/6). Diseases predisposing to infarction were not identified in 5/6 dogs. Improvements in mentation, behavior, proprioceptive deficits, and hemiparesis were seen in surviving dogs, but persistent, symptomatic sensory deficits were noted during the follow-up period. SCI should be considered as a differential diagnosis for dogs with acute onset, nonprogressive homonymous hemianopia, contralateral GP deficits or hemiparesis, and facial hypalgesia. MRI is the preferred modality for the antemortem imaging diagnosis of SCI. Although partial recovery occurred in all surviving dogs, visual and facial sensory disturbances persisted.

Iomazenil-Single-Photon Emission Computed Tomography Reveals Selective Neuronal Loss in Magnetic Resonance-Defined Mismatch Areas

The mismatch of hypoperfused tissue on perfusion imaging and ischemic tissue on diffusion-weighted imaging is used as a surrogate marker for thrombolytic therapy in the extended time window. Mismatch tissue may recover completely, progress toward infarction, or proceed toward incomplete infarction with selective loss of cortical neurons. We used [(123)I]iomazenil-single-photon emission computed tomography (IMZ-SPECT) to characterize the neuronal integrity of reperfused "tissue at risk of infarction" that appeared morphologically intact on follow-up magnetic resonance imaging (MRI). Twelve patients with acute stroke with striatocapsular (SC) infarctions were examined with multimodal MRI at days 0, 1, and 7; IMZ-SPECT was performed at days 5 to 15. The PI at day 0, fluid-attenuated inversion recovery (FLAIR) image at day 7, and IMZ-SPECT were coregistered and stereotactically normalized. The mismatch volume of interest (VOI) was defined as the initial PI lesion subtracted by the FLAIR lesion at day 7. An asymmetry ratio (AR) was computed by dividing the mean IMZ uptake of the mismatch VOI by the unaffected mirror VOI. The same AR was computed for signal intensity on FLAIR images at day 7. Three patients with cortical infarctions were included for calibration of the AR. In this group, the VOI consisted of the FLAIR lesion at day 7. All patients with SC infarctions had a large mismatch of initially hypoperfused (112+/-31 mL; mean+/-SD) and finally infarcted tissue (19+/-14 mL). Mean AR of cortical IMZ uptake was 0.85+/-0.01 in cortical infarctions and 0.95+/-0.03 in SC infarctions; thereby AR showed a continuous distribution from clearly reduced (0.89) to normal (1.01) in SC infarctions. Mean AR for FLAIR signal intensity was 1.84+/-0.14 for cortical infarctions and normal (1.01+0.03) for SC infarctions. IMZ-SPECT detected a selective loss of cortical neurons in patients with SC infarctions in transient hypoperfused tissue, which was morphologically intact on MRI.

Analysis of the Lesion Distributions and Mechanism of Acute Middle Cerebral Artery Infarctions Involving the Striatocapsular Region

Background and PurposeThere is no clear description about the patterns of each mechanism of striatocapsular infarctions. The aims of our study were to elucidate differences in the distributions of lesions of acute middle cerebral artery (MCA) infarctions involving the striatocapsular region and to compare those following embolic striatocapsular infarctions with those originating from MCA disease.MethodsWe prospectively enrolled patients with acute infarcts located in the lenticulostriate artery territory that were not lacunar infarcts. Brain coronal diffusion-weighted imaging (DWI) was obtained and magnetic resonance angiography (MRA) was carried out to evaluate the distribution of infarct lesions and MCA stenosis in all patients. The types of infarct distribution were divided into three categories: (1) dominant in the distal territory (DD), (2) distributed equally between the distal and proximal territories (DE), and (3) dominant in the proximal territory. We performed tests for embolic sources (transthoracic echocardiography, transesophageal echocardiography, Holter monitoring, and contrast-enhanced MRA including the aortic arch) in most patients. Stroke mechanisms were classified into stroke from proximal embolism, MCA disease, and stroke of undetermined etiology.ResultsA total of 47 patients (28 men and 19 women; mean age, 62 years) were recruited. A proximal embolic source was significantly more prevalent in patients with a DE lesion than in those with a DD lesion. The most common proximal embolic source was of cardiac origin. In contrast, symptomatic MCA stenoses were more common in patients with a DD lesion than in those with a DE lesion.ConclusionsThese results suggest that the dominant area of striatocapsular infarction on coronal DWI is an important clue for stroke etiology. Coronal DWI could therefore be helpful to determining the mechanisms in patients with striatocapsular infarctions that are currently described as having an "undetermined etiology" according to the Trial of Org 10172 in Acute Stroke Treatment classification.

The clinico-radiologic properties of deep small basal ganglia infarction: Lacune or small striatocapsular infarction?

Objective Deep small basal ganglia infarction (DSBI) cannot be clearly classified as either lacune or striatocapsular infarction by their sizes only. We tried to elucidate clinical and other properties of DSBI to understand better in pathophysiology of ischemic lesion of basal ganglia. Methods We analyzed 36 patients with acute ischemic lesion of basal ganglia with the size varying from 1.5 to 3 cm in maximal diameters. We assessed clinical features, laboratory data, risk factors of stroke, and radiologic findings such as MRI and MR angiography. Results Patients with DSBI could be largely divided into two distinctive groups, small infarction with cortical sign (SICS) and lacunar syndrome (LS) according to their presence of cortical manifestations. Total of 11 patients were in SICS group and they showed cortical manifestations such as eyeball deviation, visual field defect, aphasia and neglect. They also showed severer non-cortical neurologic deficit compared with LS group. Whereas LS group showed various MRA patterns, 7 patients of SICS group (63.6%) showed proximal MCA stenosis in MRA. Conclusions We found that many patients with DSBI could have the features of either lacune or striatocapsular infarction. Although they have similar morphologic characteristics but they are presumed to have different pathophysiologic mechanism.

Aphasia following Striatocapsular Infarction May Be Explained by Concomitant Small Cortical Infarct on Diffusion-Weighted Imaging

Background: The underlying mechanism of aphasia following striatocapsular infarction (SCI) remains controversial. We hypothesized that aphasia resulting from SCI might be associated with concomitant cortical lesions, which can be demonstrated by diffusion-weighted imaging (DWI). Methods: We analyzed 24 patients with left SCI who underwent DWI and MR angiography within 2 days after the onset. Aphasia was assessed by the modified Korean version of the Boston Diagnostic Aphasia Examination test. Results: DWI showed the presence of additional ischemic lesions involving the cortical areas in 13 of 24 SCI patients (54%). Ten patients (42%) showed aphasia. All 10 patients with aphasia had cortical lesions in addition to SCI (p = 0.0002), whereas 21% (3/14) of the nonaphasic patients had additional cortical lesions. Conventional MRI did not reveal the presence of corresponding acute cortical lesions in any of the aphasic patients. There was no difference between the patients with and without aphasia in terms of their stroke etiology. Conclusions: Our data suggest that aphasia due to SCI in the acute stage may be attributed to direct cortical injury, whose presence can be demonstrated by DWI, even though it might be invisible on conventional imaging.

Imaging

Imaging

Pattern of collaterals, type of infarcts, and haemodynamic impairment in carotid artery occlusion

Background: In internal carotid artery (ICA) occlusion, increased oxygen extraction fraction (OEF) indicates inadequate collateral blood flow distal to the occlusion, which may be caused by poor function of collateral...