Prehospital triage of patients with suspected stroke symptoms (PRESTO): protocol of a prospective observational study

INTRODUCTION

The efficacy of both intravenous treatment (IVT) and endovascular treatment (EVT) for patients with acute ischaemic stroke strongly declines over time. Only a subset of patients with ischaemic stroke caused by an intracranial large vessel occlusion (LVO) in the anterior circulation can benefit from EVT. Several prehospital stroke scales were developed to identify patients that are likely to have an LVO, which could allow for direct transportation of EVT eligible patients to an endovascular-capable centre without delaying IVT for the other patients. We aim to prospectively validate these prehospital stroke scales simultaneously to assess their accuracy in predicting LVO in the prehospital setting.

METHODS AND ANALYSIS

Prehospital triage of patients with suspected stroke symptoms (PRESTO) is a prospective multicentre observational cohort study in the southwest of the Netherlands including adult patients with suspected stroke in the ambulance. The paramedic will assess a combination of items from five prehospital stroke scales, without changing the normal workflow. Primary outcome is the clinical diagnosis of an acute ischaemic stroke with an intracranial LVO in the anterior circulation. Additional hospital data concerning the diagnosis and provided treatment will be collected by chart review. Logistic regression analysis will be performed, and performance of the prehospital stroke scales will be expressed as sensitivity, specificity and area under the receiver operator curve.

ETHICS AND DISSEMINATION

The Institutional Review Board of the Erasmus MC University Medical Centre has reviewed the study protocol and confirmed that the Dutch Medical Research Involving Human Subjects Act (WMO) is not applicable. The findings of this study will be disseminated widely through peer-reviewed publications and conference presentations. The best performing scale, or the simplest scale in case of clinical equipoise, will be integrated in a decision model with other clinical characteristics and real-life driving times to improve prehospital triage of suspected stroke patients.

TRIAL REGISTRATION NUMBER

NTR7595.

Confined anterior cerebral artery infarction manifesting as isolated unilateral axial weakness

We describe isolated unilateral axial weakness in three patients eventually diagnosed with anterior cerebral artery infarction (ACAI), a new clinical observation. Files of three ACAI patients (2 females, 1 male, ages 55-80) were retrospectively reviewed. All three presented to the ED with sudden unsteadiness. On initial neurological examination, all three patients manifested unilateral truncal deviation to the side contralateral to the weakness, even while seated. There was significant unilateral hypotonia due to substantial paravertebral weakness. None had pyramidal signs or increased limb tone. Speech, language, and cognitive performance were intact during admission examination. In all three patients, initial diffusion-weighted imaging (DWI) MRI showed small confined regions of restriction involving the posterolateral border of ACA territory; CT angiography was normal in one patient with a newly diagnosed atrial fibrillation but showed atherosclerotic vasculature with severe narrowing of the A3 segment of the ACA in two. Awareness of ACAI presenting as unilateral axial weakness is warranted. We suggest that optimal diagnostic management should include examination of axial tone. Ischemic involvement of distal ACA branches may herald a more extensive ACAI. Prompt diagnosis may enable thrombolysis or endovascular treatment, and blood pressure maintenance may allow adequate perfusion to damaged tissue.

Endovascular procedures versus intravenous thrombolysis in stroke with tandem occlusion of the anterior circulation

PURPOSE

Stroke with tandem occlusion within the anterior circulation presents a lower probability of recanalization and good clinical outcome after intravenous (IV) thrombolysis than stroke with single occlusion. The present study describes the impact of endovascular procedures (EPs) compared with IV thrombolysis alone on recanalization and clinical outcome.

MATERIALS AND METHODS

Thirty patients with symptom onset less than 4.5 hours and tandem occlusion within the anterior circulation were analyzed retrospectively. Recanalization was assessed per Thrombolysis In Cerebral Infarction (TICI) classification on computed tomography, magnetic resonance imaging, or digital subtraction angiography within 24 hours. Infarct size was detected on follow-up imaging as a dichotomized variable, ie, more than one third of the territory of the middle cerebral artery. Clinical outcomes were major neurologic improvement, independent outcome (90-d modified Rankin Scale [mRS] score), symptomatic intracerebral hemorrhage (sICH; per European Cooperative Acute Stroke Study criteria), and death within 7 days.

RESULTS

Patients treated with EPs (n = 14) were significantly younger and had a history of arterial hypertension more frequently than patients treated with IV thrombolysis alone (n = 16). Recanalization (ie, TICI score 2b/3; EP, 64%; IV, 19%; P = .01), major neurologic improvement (EP, 64%; IV, 19%; P = .01), and independent outcome (mRS score ≤ 2; EP, 54% IV, 13%; P = .02) occurred more often in the EP group, whereas infarct sizes greater than one third of the MCA territory (EP, 43%; IV, 81%; P = .03) were observed less often. Rates of sICH (P = .12) and death within 7 days (P = .74) did not differ significantly.

CONCLUSIONS

Higher recanalization rate, smaller infarct volume, and better clinical outcome in the EP group should encourage researchers to include this subgroup of patients in prospective randomized trials comparing IV thrombolysis versus EP in stroke.

[Traumatic dissection of extra- and intradural arteries]

Dissection of extra- and intradural arteries is a common cause of cerebral insult in younger patients (<45 years). In patients with corresponding craniocervical injury and symptoms (carotidynie, ipsilateral headache, partial Horner syndrome, cranial nerve palsy) arterial dissection is always to be considered. Essential in diagnosing arterial dissection is the verification of the intramural hematoma and morphologic changes in the vessel (stenosis, pseudoaneurysm) by means of CT/CTA (acute phase) or MRI/MRA (subacute phase). These patients need to be monitored in an intensive care unit setting. The acute therapy includes anticoagulation or inhibition of thrombocyte aggregation. We present two cases with delayed cerebral infarction due to traumatic extra- and intradural arterial dissection after a motor vehicle accident. To perform primary diagnostic quickly and adequately may avoid permanent neurological deficit in these patients.

Subarachnoid Hemorrhage and Vasospastic Stroke After Self-Enucleation

A 31-year-old intoxicated woman self-enucleated her left eye during an acute psychotic episode. CT revealed avulsion of the intracranial optic nerve, chiasmal edema, and adjacent subarachnoid hemorrhage. Exploration via transconjunctival orbitotomy was performed, and the globe and 4.8 cm of contiguous optic nerve were removed. The patient developed postoperative contralateral visual loss followed by middle cerebral artery vasospasm and bilateral cortical infarcts.

Migrainous infarction with appearance of laminar necrosis on MRI

Although there is accepted criteria for migrainous infarction, the pathophysiology of this disease process remains poorly defined. Delineation of MRI characteristics of migrainous infarction may improve our understanding of the pathophysiology, diagnosis, and prognosis of this disorder. We present a case of a migrainous infarction that involved apparent laminar necrosis of a "cortical ribbon" of the right temporal, parietal, and occipital lobes.

Angioinvasive cerebral aspergillosis presenting as acute ischaemic stroke in a patient with diabetes mellitus

Cerebral angioinvasive aspergillosis is a rare manifestation of disseminated aspergillosis which may result in stroke in immunocompromised individuals. Reports of such disease in patients with diabetes mellitus are rare. We describe a 45-year-old man with diabetes mellitus who presented with a three-day history of right-sided limb weakness and aphasia. Cerebral computed tomography showed features of an acute infarct involving the left anterior and middle cerebral arteries. He was initially treated for an acute ischaemic stroke. Further history revealed that he was investigated for a growth in the sphenoid sinus two months earlier. Culture of the biopsied material from the sphenoid sinus grew Aspergillus fumigatus. Magnetic resonance imaging showed an extension of the growth to the brain, causing the acute ischaemic stroke. He was subsequently diagnosed with angioinvasive cerebral aspergillosis and was commenced on intravenous amphotericin B. Unfortunately, he succumbed to his illness despite treatment.

Pharmakologische Zusatzbehandlung in der Aphasietherapie

Aphasia is one of the most frequent and disabling consequences of stroke. Poor spontaneous recovery and the limited success of conventional speech therapy bring up the question of how current treatment approaches can be improved. Besides increasing training frequency-with daily sessions lasting several hours and high repetition rates of language materials ("massed training")-adjuvant drug therapy may help to increase therapy efficacy. In this article, we illuminate the potential of monoaminergic (bromocriptine, levodopa, d-amphetamine) and cholinergic (donepezil) substances for treating aphasia. For a final evaluation of combined massed training and adjuvant pharmacotherapy, randomized, placebo-controlled (multicenter) clinical trials with sufficient numbers of patients are needed. Furthermore, results of experimental animal studies of functional recovery in brain damage raise hopes that neurotrophic factors or stem cells might find a place in recovery from aphasia in the intermediate future.

[A case of anterior cerebral artery dissection causing enlargement of infarction]

A 46-year-old woman presented with weakness in the right arm and leg. She had developed difficulty in moving the right arm and leg while exercising and had noticed headache simultaneously. On admission, she had hemiparesis of the right side. Angiography on day 1 disclosed irregularity of the left anterior cerebral artery (ACA). We started argatroban and aspirin to prevent exacerbation of ischemia. Diffusion-weighted MR image on day 2 disclosed acute infarction in the territory of the left ACA. When she became able to move her leg against gravity (MMT 3/5), we discontinued antithrobotic therapy on day 3. MRI on day 10 disclosed enlargement of the infarcted area. Angiography on day 16 disclosed stenosis and dilation corresponding to pearl and string sign involving the left ACA. Spontaneous ACA dissection was established based on clinical features and angiographic findings. Antithrombotic therapy in patients with intracranial artery dissection remains controversial because subarachnoidal hemorrhage can complicate the course due to rupture of dissecting aneurysm, for there is no external elastic lamina in intracranial arteries. However, some cases of ACA dissection have showen progression of ischemic symptoms and enlargement of the infarcted area during the acute or subacute phase.

Mechanisms of Recurrence in Subtypes of Ischemic Stroke

BACKGROUND

Information on the mechanism of recurrent stroke may help physicians treating patients with ischemic stroke. However, the mechanisms of recurrence in each stroke subtype are not well known, especially in Asians.

OBJECTIVE

To compare the mechanisms of the index and recurrent stroke.

DESIGN

Analysis of data from a prospective acute stroke registry.

SETTING

University hospital.

PATIENTS

Using the clinical syndrome, diffusion-weighted imaging, and vascular studies, we divided 901 patients into 5 groups: large-artery atherosclerosis, cardioembolism, small-artery disease, parent-artery disease occluding the deep perforators, and no determined cause. The patients with large-artery atherosclerosis were subdivided into 2 groups: intracranial and extracranial.

MAIN OUTCOME MEASURES

The mechanisms of recurrent vascular events (strokes or coronary heart disease) in subtypes of ischemic stroke were compared.

RESULTS

Ninety-three recurrent vascular events (86 strokes and 7 instances of coronary heart disease) were evaluated. The pattern of recurrent stroke differed for the intracranial and extracranial groups; unlike the patients with intracranial large-artery atherosclerosis, recurrent strokes in the extracranial group were often unpredictable with respect to the site of recurrence and degree of preexisting stenosis. None of the patients in the extracranial group had recurrences that were caused by intracranial large-artery atherosclerosis or vice versa. In patients with small-artery disease and stroke with no determined cause, intracranial stenosis was often found at the time of recurrence.

CONCLUSIONS

From prognostic and therapeutic perspectives, patients with atherosclerosis should be divided into those with intracranial large-artery atherosclerosis and extracranial large-artery atherosclerosis. In addition, intracranial large-artery atherosclerosis may be important in the development of small-artery disease and stroke with no determined cause, especially in the population with a higher frequency of intracranial large-artery atherosclerosis.

Is stroke a paradoxical embolism in patients with patent foramen ovale?

OBJECTIVE

Purpose was to assess the stroke mechanism in patients with patent foramen ovale (PFO).

METHODS

We reviewed the medical records of 111 stroke patients with PFO and sinus rhythm (PFO-S group), 25 with PFO and atrial fibrillation (AF) (PFO-AF group) and 67 with AF but not PFO (AF group), who had received contrast transesophageal echocardiography. The clinical and neuroradiological findings were then compared among the three groups. Deep vein thrombosis was investigated in 93 patients with PFO. We determined the number of patients with definite paradoxical embolism who met three criteria: deep vein thrombosis, neuroradiological features indicating embolic stroke, and the absence of other sources of emboli. We also evaluated those with probable paradoxical embolism who met two of the three criteria.

RESULTS

The PFO-S group more frequently exhibited hypercholesterolemia (p<0.0001) and lesions limited to the posterior circulation (p<0.0004), and less frequently exhibited large or cortical lesions in the anterior circulation (p=0.0008, p<0.0001, respectively), than the PFO-AF and AF groups. In the PFO-S and PFO-AF groups, other sources of emboli such as a cardiac source of emboli, cerebral artery stenosis > or =50%, or complicated atheroma in the aortic arch were identified in 72 cases (52.9%). In the 93 patients with examination for deep vein thrombosis, the definite and probable criteria of paradoxical embolism were fulfilled only in three (3.2%) and 33 cases (35.5%), respectively.

CONCLUSION

In stroke patients with PFO, not only paradoxical brain embolism through the PFO but also other causes of stroke may contribute to the development of stroke.

[Ischemic brain infarction after an air embolism. Case report]

Ischemic stroke due to embolic air is uncommon. There are few reports of patients with air embolic stroke as a complication of endoscopic procedures. The temporal relationship between the stroke and this procedure is the most important clue for the diagnosis. CT scan and MRI of the brain are confirmatory tests. The morbidity and mortality is high. Patients should be hospitalized in a critical care service and treated as soon as possible with oxygen in a pressure camera. We report a 52 years old woman with an ovarian cancer that, during an upper gastrointestinal endoscopy, had a severe alteration of consciousness that did not respond to the use of Flumazenil. A CT scan showed multiple areas of air embolism in the watershed area between anterior and middle right cerebral arteries. A conservative treatment was decided and the patients died 48 hours later.

[A case of anterior cerebral artery dissection causing hemorrhagic infarction]

A 56-year-old man presented with weakness in his right arm and leg. Throbbing headache occurred several hours prior to his weakness. Brain CT obtained on day 3 demonstrated low density areas in the medial part of the left frontal lobe. Cerebral angiography on day 14 demonstrated dilatation and narrowing of the left anterior cerebral artery (ACA) corresponding to "pearl and string sign". The diagnosis of spontaneous ACA dissection was established with clinical features, laboratory findings, and angiographic findings. Antiplatelet therapy was undertaken for the prevention of ischemic events. Serial Brain CT demonstrated hemorrhagic change in the area of infarction. However, there was no definite clinical deterioration. Antiplatelet therapy was withdrawn after hemorrhagic change was noted. Cerebral angiography on day 35 showed improvement of both dilatation and narrowing. Possible reperfusion injury caused by absorption of intramural hematoma seems to be responsible for hemorrhagic change. In patients with cerebral infarction due to dissection of intracranial arteries, antithrombotic therapy is controversial as hemorrhagic complications including hemorrhagic infarction as well as subarachnoidal hemorrhage can occur. Further accumulation of cases is required.

Accuracy of dynamic perfusion CT with deconvolution in detecting acute hemispheric stroke

BACKGROUND AND PURPOSE

Dynamic perfusion CT (PCT) with deconvolution produces maps of time-to-peak (TTP), mean transit time (MTT), regional cerebral blood flow (rCBF), and regional cerebral blood volume (rCBV), with a computerized automated map of the infarct and penumbra. We determined the accuracy of these maps in patients with suspected acute hemispheric stroke.

METHODS

Forty-six patients underwent nonenhanced CT and dynamic PCT, with follow-up CT or MR imaging. Two observers reviewed the nonenhanced studies for signs of stroke and read the PCT maps for TTP, MTT, rCBF, and rCBV abnormalities. Sensitivity, specificity, accuracy, and interobserver agreement were compared (Wilcoxon tests). Nonenhanced CT and PCT data were reviewed for stroke extent according to previously reported methods. Sensitivity, specificity, and accuracy of the computerized maps in detecting ischemia and its extent were determined.

RESULTS

Compared with nonenhanced CT, PCT maps were significantly more accurate in detecting stroke (75.7-86.0% vs. 66.2%; P <.01), MTT maps were significantly more sensitive (77.6% vs. 69.2%; P <.01), and rCBF and rCBV maps were significantly more specific (90.9% and 92.7%, respectively, vs. 65.0%; P <.01). Regarding stroke extent, PCT maps were significantly more sensitive than nonenhanced CT (up to 94.4% vs. 42.9%; P <.01) and had higher interobserver agreement (up to 0.763). For the computerized map, sensitivity, specificity, and accuracy, respectively, were 68.2%, 92.3%, and 88.1% in detecting ischemia and 72.2%, 91.8%, and 87.9% in showing the extent.

CONCLUSION

Dynamic PCT maps are more accurate than nonenhanced CT in detecting hemispheric strokes. Despite limited spatial coverage, PCT is highly reliable to assess the stroke extent.

Postpartum cerebral angiopathy: atypical features and treatment with intracranial balloon angioplasty

Postpartum cerebral angiopathy (PCA) is an uncommon cause of ischemic and hemorrhagic stroke in young women. It is usually clinically benign and not relapsing. We describe a patient with nonhemorrhagic PCA who had an atypical progressive neurological deficit from bilateral hemisphere watershed ischemia despite treatment with aggressive medical therapy and intracranial balloon angioplasty.

Aphemia-like syndrome from a right supplementary motor area lesion

Lesions in the left supplementary motor area (SMA) can result in a transcortical motor aphasia with nonfluent spontaneous verbal output and relatively preserved repetition. Reading and writing are proportionally affected. We report a patient with an ischemic lesion in the right SMA. He had impaired articulation and normal repetition plus preserved reading and writing, consistent with an aphemia. This patient supports the dissociation of articulatory fluency and linguistic fluency and suggests that both SMAs affect the initiating of articulatory movements required to produce words whereas the left SMA also affects linguistic aspects of speech.

Bilateral anterior cerebral artery territory infarction associated with unilateral hypoplasia of the A1 segment: report of two cases

We report two cases of bilateral anterior cerebral artery (ACA) territory infarction. On magnetic resonance (MR) angiograms, the A1 segment of the ACA was unilaterally hypoplastic in both cases, suggesting that unilateral hypoplasia of A1 is a significant predisposing factor for this rare type of cerebral infarction. When the contralateral A1 is dominant, embolic materials may enter into it more easily.

Stroke in young patients: a diagnostic challenge in the emergency room

Stroke in young adults has been related to mechanisms different to those found in older individuals. Cardiogenic embolism, arteritis, atherosclerosis, fibromuscular dysplasia, pregnancy-related angiopathy, migrainous stroke, anaemia, antiphospholipid syndrome, arterial dissection, the consumption of toxic substances and head trauma have been described. We present a young man with a case history of tobacco and cocaine abuse who suffered a mild head trauma, with normal neurological examination, and a computed tomography scan image of a right anterior cerebral infarction. Serum biochemistry showed no alterations according to the diagnosis protocol for stroke in young patients. Various mechanisms have been involved, such as vasospasm, increasing arterial pressure and embolism. Considering the cocaine abuse and the mild head trauma, in our patient vasospasm was thought to be the mechanism involved in the cerebral infarction, which proved a challenge to diagnose in the emergency room.

Anterior inferior cerebellar artery infarct with unilateral deafness

We report the case of a young man with anterior inferior cerebellar artery infarct causing unilateral deafness. Clinical features and audiometry suggested cochlear localization for deafness. MRI brain showed an infarct in the right AICA territory with involvement of pons. Involvement of the internal auditory artery explains the cochlear deafness.

Distinguishing between anterior cerebral artery and middle cerebral artery perfusion by color-coded perfusion direction mapping with arterial spin labeling

The purpose of this study was to evaluate collateral circulation by describing anterior cerebral artery and middle cerebral artery perfusion areas. Pairs of image sets spin labeled on the medial and lateral side were used. A pixel-by-pixel t test was performed, with blue gradation used to display lateral perfusion (ie, middle cerebral artery) and orange gradation for anterior cerebral artery perfusion. Extensions of anterior cerebral artery perfusion areas in cases of middle cerebral artery stenosis were described. This method may aid in estimation of collateral circulation for stroke treatment.

Diffusion-weighted imaging of acute corticospinal tract injury preceding Wallerian degeneration in the maturing human brain

BACKGROUND AND PURPOSE

Wallerian degeneration, the secondary degeneration of axons from cortical and subcortical injury, is associated with poor neurologic outcome. Since diffusion-weighted (DW) imaging is sensitive to early changes of cytotoxic edema, DW imaging may depict the acute injury to descending white matter tracts that precedes Wallerian degeneration; this injury is not visible on conventional CT or MR images in the maturing human brain.

METHODS

Two neuroradiologists retrospectively analyzed clinical MR images in six children (aged 3 days to 5 months) with DW findings consistent with acute injury of the descending white matter tract due to territorial anterior or middle cerebral artery infarction. In five patients, images were obtained as a part of routine clinical evaluation. The remaining patient was a part of a prospective study of brain injury. Imaging findings were correlated with clinical outcomes.

RESULTS

In all six patients, DW imaging performed 2-8 days after the onset of ischemia depicted injury to the descending white matter tract ipsilateral to the territorial infarct. Conventional MR images of the ipsilateral descending white matter tracts were abnormal in three patients. In all five patients for which follow-up results were available, the presence of DW changes was correlated with persistent neurologic disability.

CONCLUSION

As shown in this retrospective analysis, DW imaging can depict acute injury to the descending white matter tract in neonates and infants, when conventional MR imaging may show normal findings. These DW findings likely precede the development of Wallerian degeneration, and they may portend a poor clinical outcome.

Neuroradiologic and clinical features of arterial dissection of the anterior cerebral artery

BACKGROUND AND PURPOSE

Case reports of nontraumatic arterial dissection of the anterior cerebral artery (ACA) have recently increased. The aim of this study was to investigate the neuroradiologic and clinical features of ACA dissection based on a series of collected cases.

METHODS

The cases of 18 patients with a diagnosis of ACA dissection based on clinical signs and neuroradiologic findings from 46 stroke centers during a 5-year period were collected. The neuroradiologic and clinical records were analyzed.

RESULTS

The mean patient age was 52.8 +/- 9.8 years. Five cases presented with subarachnoid hemorrhage, nine with cerebral ischemia, and four with both ischemic symptoms and subarachnoid hemorrhage. In cases presenting with ischemia, the main site of the lesion was the A2 portion and the main angiographic finding was stenosis with or without dilation. Follow-up angiography showed progression of the stenosis in the acute stage and resolution of the stenosis in the chronic stage. Hyperintensity around the flow void due to intramural hematoma on T1-weighted MR images was often seen during the second week. In all cases, the findings of MR angiography corresponded to the findings of cerebral angiography. Eight of nine cases showed a good prognosis. In three of the patients with bleeding, in whom the site of the lesion was at the A1 portion, a diffuse thick subarachnoid hemorrhage was present and surgical treatment was required but resulted in a poor prognosis. In the other patients with bleeding, in whom the site of the lesion was at the distal ACA, the prognosis was good and no rebleeding or need for surgical treatment occurred.

CONCLUSION

ACA dissection presenting with ischemia has several identifiable neuroradiologic and clinical characteristics, which suggests that it may be classified as a unique clinical entity.

Early carotid endarterectomy after ischemic stroke improves diffusion/perfusion mismatch on magnetic resonance imaging: report of two cases

OBJECTIVE AND IMPORTANCE

The functional magnetic resonance imaging techniques of diffusion-weighted imaging and perfusion-weighted imaging allow for ultra-early detection of brain infarction and concomitant identification of blood flow abnormalities in surrounding regions, which may represent brain "at risk."

CLINICAL PRESENTATION

We report two patients with acute ischemic stroke associated with ipsilateral high-grade carotid stenosis. The first patient, a 64-year-old woman with a remote history of ischemic stroke and a vertebral artery aneurysm, presented with worsening of her preexisting right hemiparesis. The second patient, another 64-year-old woman with known multiple intracranial aneurysms and bilateral high-grade internal carotid artery stenosis, was admitted for the elective microsurgical clipping of an enlarging giant left carotid-ophthalmic artery aneurysm. Postoperatively, she developed right hemiparesis and mild aphasia. Both patients showed progressive worsening of their neurological deficits in the setting of small or undetected diffusion-weighted imaging abnormalities and large perfusion-weighted imaging defects.

INTERVENTION

After prompt carotid endarterectomy, symptoms in both patients resolved or improved. Follow-up magnetic resonance imaging scans demonstrated resolution or significant improvement in the perfusion abnormalities in both patients.

CONCLUSION

Carotid endarterectomy in the setting of diffusion-weighted/perfusion-weighted imaging mismatch can lead to improvement in cerebral perfusion as evidenced by resolution of the perfusion-weighted imaging lesion. Diffusion/perfusion magnetic resonance imaging may be useful in identifying patients with severe neurological deficits but without large territories of infarction who may safely undergo early surgical revascularization.

Spectrum of anterior cerebral artery territory infarction: clinical and MRI findings

To evaluate and review the clinical spectrum of anterior cerebral artery (ACA) territory infarction, we studied 48 consecutive patients who admitted to our stroke unit over a 6-year period. We performed magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) in all patients, and diffusion magnetic resonance imaging (DWI) in 21. In our stroke registry, patients with ACA infarction represented 1.3% of 3705 patients with ischemic stroke. The main risk factors of ACA infarcts was hypertension in 58% of patients, diabetes mellitus in 29%, hypercholesterolemia in 25%, cigarette smoking in 19%, atrial fibrillation in 19%, and myocardial infarct in 6%. Presumed causes of ACA infarct were large-artery disease and cardioembolism in 13 patients each, small-artery disease (SAD) in the territory of Heubner's artery in two and atherosclerosis of large-arteries (<50% stenosis) in 16. On clinico-radiologic analysis there were three main clinical patterns depending on lesion side; left-side infarction (30 patients) consisting of mutism, transcortical motor aphasia, and hemiparesis with lower limb predominance; right side infarction (16 patients) accompanied by acute confusional state, motor hemineglect and hemiparesis; bilateral infarction (two patients) presented with akinetic mutism, severe sphincter dysfunction, and dependent functional outcome. Our findings suggest that clinical and etiologic spectrum of ACA infarction may present similar features as that of middle cerebral artery infarction, but frontal dysfunctions and callosal syndromes can help to make a clinical differential diagnosis. Moreover, at the early phase of stroke, DWI is useful imaging method to locate and delineate the boundary of lesion in the territory of ACA.

Utilisation behaviour consequent to bilateral SMA softening

The case of patient CU, who presented with severe utilisation behaviour, eventually unaccompanied by psychometric signs of frontal involvement, is reported. He suffered from a bilateral stroke within the territory of the anterior cerebral artery. His arterial system was characterised by a unique variant, whereby the right anterior cerebral artery was missing and three trunks originated from the left anterior cerebral artery, each bifurcating into right and left branches. An occlusion of the middle trunk immediately before its partition gave rise to a symmetrical bilateral parasagittal lesion that damaged the supplementary motor areas (medial part of Brodmann's area 6), sparing the lateral regions including the premotor cortices, the corpus callosum and the gyri cinguli. The hypothesis is put forward that utilisation behaviour should be conceived as a double anarchic hand, and its interpretation should rest on the damaged balance between the premotor cortices, responsive to environmental triggers, and the supplementary motor areas, which modulate actions and inhibit them. The imbalance due to the lesion would result in the patients being left at the mercy of environmental stimuli, unable to inhibit inappropriate actions. This intra-frontal hypothesis accounts for the data presented and those from the literature better than the previously held fronto-parietal equipoise.

Reversible vascular changes in children with cerebral infarction

A case of cerebral infarction in a 4-year-old male is described. The child presented with an acute onset of right hemiplegia, central facial palsy, and dysarthria. He had no predisposing factors for cerebral infarction. A computed tomography scan showed a diffuse low-density area in the territory of the left miiddle cerebral artery. Magnetic resonance angiography disclosed multiple irregular narrowings in the left anterior and middle cerebral arteries. He recovered spontaneously from the stroke with minimal long-term complications, and repeated angiography disclosed a complete regression of the vascular changes 2 months after the stroke. There was no recurrence of stroke after 2-year follow-up. This case demonstrates the importance of longitudinal angiographic follow-up in childhood cerebral infarction of idiopathic origin.

Combined encephaloduroarteriosynangiosis and bifrontal encephalogaleo(periosteal)synangiosis in pediatric moyamoya disease

OBJECTIVE

We compared the surgical results of simple encephaloduroarteriosynangiosis (EDAS) and EDAS with bifrontal encephalogaleo(periosteal)synangiosis for the treatment of pediatric moyamoya disease.

METHODS

Data for 159 children (up to 15 yr of age, 76 boys and 83 girls) who underwent indirect revascularization procedures for the treatment of moyamoya disease between 1987 and 1998 were retrospectively reviewed. Group A patients underwent simple EDAS (n = 67). Group B patients underwent EDAS with bifrontal encephalogaleo(periosteal)synangiosis (n = 92). The surgical results for each group were compared, in terms of clinical outcomes, neuroimaging changes, extent of revascularization evident on angiograms, and hemodynamic changes evident on single-photon emission computed tomographic scans. The average follow-up periods were 45 months for Group A and 22 months for Group B.

RESULTS

The overall clinical outcomes and neuroimaging changes tended to be better for Group B. In terms of single-photon emission computed tomographic changes of the whole brain after surgery, Group B patients exhibited more favorable outcomes than did Group A patients (62 versus 36%, P = 0.003). The surgical results for the anterior cerebral artery territory were significantly better for Group B than for Group A, with respect to outcomes of anterior cerebral artery symptoms (81 versus 40%, P = 0.015), revascularization on angiograms (79 versus 16%, P < 0.001), and hemodynamic changes on single-photon emission computed tomographic scans (70 versus 52%, P = 0.002). The incidences of postoperative infarctions were not significantly different between the two groups.

CONCLUSION

EDAS with bifrontal encephalogaleo(periosteal)synangiosis is a more effective surgical modality for the treatment of pediatric moyamoya disease, compared with simple EDAS, because it covers both the middle cerebral artery and anterior cerebral artery territories of the brain.

Gait apraxia after bilateral supplementary motor area lesion

OBJECTIVES

The study aimed at addressing the issue of the precise nature of gait apraxia and the cerebral dysfunction responsible for it.

METHODS

The case of a patient, affected by a bilateral infarction limited to a portion of the anterior cerebral artery territory is reported. The patient's ability to walk was formally assessed by means of a new standardised test.

RESULTS

Due to an anomaly within the anterior cerebral artery system, the patient's lesion was centred on the supplementary motor regions of both hemispheres. He presented with clear signs of gait apraxia that could not be accounted for by paresis or other neurological deficits. No signs of any other form of apraxia were detected.

CONCLUSIONS

The clinical profile of the patient and the analysis of 49 cases from previous literature suggest that gait apraxia should be considered a clinical entity in its own right and lesions to the supplementary motor areas are responsible for it.

Posttraumatic isolated infarction in the territory of Heubner's and lenticulostriate arteries: case report

A 12 year old male had a secondarily generalized epileptic seizure and a subsequent right hemiparesis with fasciobrachial predominance after a closed head injury. His seizures responded to antiepileptic drug therapy immediately. Computerized tomographic scanning and magnetic resonance imaging showed an acute infarct of the head of the left caudate nucleus, indicating the isolated occlusion of the left recurrent artery of Heubner and lateral lenticulostriate arteries. Pathologies leading to vasculitis and embolism were also looked for, but no finding of associated systemic disease could be disclosed. We present this case since posttraumatic infarction in the territory of the deep perforators such as recurrent artery of Heubner and lateral lenticulostriate arteries are exceptionally rare conditions especially in this age group.

Transtentorial herniation after unilateral infarction of the anterior cerebral artery

BACKGROUND

Fatal cerebral herniation is a common complication of large ("malignant") middle cerebral artery infarcts but has not been reported in unilateral anterior cerebral artery (ACA) infarction.

CASE DESCRIPTION

We report a 47-year-old woman who developed an acute left hemiparesis during an attack of migraine. Cranial CT (CCT) was normal but demonstrated narrow external cerebrospinal fluid compartments. Transcranial Doppler sonography was compatible with occlusion of the right ACA. Systemic thrombolytic therapy with tissue plasminogen activator was initiated 105 minutes after symptom onset. Follow-up CCT 24 hours after treatment revealed subtotal ACA infarction with hemorrhagic conversion. Two days later, the patient suddenly deteriorated with clinical signs of cerebral herniation, as confirmed by CCT. An extended right hemicraniectomy was immediately performed. Within 6 months, the patient regained her ability to walk but remained moderately disabled.

CONCLUSIONS

This is the first reported case of unilateral ACA infarct leading to almost fatal cerebral herniation. Narrow external cerebrospinal fluid compartments in combination with early reperfusion, hemorrhagic transformation, and additional dysfunction of the blood-brain barrier promoted by tissue plasminogen activator and migraine may have contributed to this unusual course.

Involuntary movements after anterior cerebral artery territory infarction

BACKGROUND AND PURPOSE

Patients with anterior cerebral artery territory infarction presenting with involuntary movements have rarely been described in the literature.

CASE DESCRIPTIONS

The author reports 9 such patients: 3 with asterixis, 5 with hemiparkinsonism (tremor, rigidity, hypokinesia), and 1 with both. Asterixis developed in the acute stage in patients with minimal arm weakness, whereas parkinsonism was usually observed after the motor dysfunction improved in patients with initially severe limb weakness. Asterixis correlated with small lesions preferentially involving the prefrontal area; parkinsonism is related to relatively large lesions involving the supplementary motor area.

CONCLUSIONS

Anterior cerebral artery territory infarction should be included in the differential diagnosis of asterixis and hemiparkinsonism.

Whole brain quantitative CBF, CBV, and MTT measurements using MRI bolus tracking: implementation and application to data acquired from hyperacute stroke patients

A robust whole brain magnetic resonance (MR) bolus tracking technique based on indicator dilution theory, which could quantitatively calculate cerebral blood flow (CBF), cerebral blood volume (CBV), and mean transit time (MTT) on a regional basis, was developed and tested. T2*-weighted gradient-echo echoplanar imaging (EPI) volumes were acquired on 40 hyperacute stroke patients after gadolinium diethylene triamine pentaacetic acid (Gd-DTPA) bolus injection. The thalamus, white matter (WM), infarcted area, penumbra, and mirror infarcted and penumbra regions were analyzed. The calculation of the arterial input function (AIF) needed for absolute quantification of CBF, CBV, and MTT was shown to be user independent. The CBF values (ml/min/100 g units) and CBV values (% units, in parentheses) for the thalamus, WM, infarct, mirror infarct, penumbra, and mirror penumbra (averaged over all patients) were 69.8 +/- 22.2 (9.0 +/- 3.0 SD); 28.1 +/- 6.9 (3.9 +/- 1.2); 34.4 +/- 22.4 (7.1 +/- 2.7); 60.3 +/- 20.7 (8.2 +/- 2.3); 50.2 +/- 17.5 (10.4 +/- 2.4); and 64.2 +/- 17.0 (9.5 +/- 2.3), respectively, and the corresponding MTT values (in seconds) were 8.0 +/- 2.1; 8.6 +/- 3.0; 16.1 +/- 8.9; 8.6 +/- 2.9; 13.3 +/- 3.5; and 9.4 +/- 3.2. The infarct and penumbra CBV values were not significantly different from their corresponding mirror values, whereas the CBF and MTT values were (P < 0.01). Quantitative measurements of CBF, CBV, and MTT were calculated on a regional basis on data acquired from hyperacute stroke patients, and the CBF and MTT values showed greater sensitivity to areas with perfusion defects than the CBV values. J. Magn. Reson. Imaging 2000;12:400-410.

Recurrent artery of Heubner infarction in infancy

Classically, acquired occlusion of the recurrent artery of Heubner (RAH) results in hemiparesis with faciobrachial predominance. Infarction in the territory of the RAH represents a specific stroke syndrome not yet described in infancy with a range of motor and functional manifestations. An infant is described with apparent congenital infarction of the recurrent artery of Heubner. The child had prominent involvement of the contralateral upper extremity with athetosis. Neuroimaging changes were evident in the vascular territory classically attributed to the RAH. The clinician should suspect congenital RAH infarction in those infants with congenital upper-extremity athetosis.

Watershed infarction associated with dementia and cerebral atrophy

A 63-year-old man was admitted with progressive left hemiparesis and left homonymous hemianopsia of 1 month's duration. During the 2 months before admission, he had suffered from slowly progressive dementia. The diagnosis of right-sided watershed (WS) infarction was made. He exhibited slow progression of dementia and cerebral atrophy during the period of observation after discharge. There was a positive relationship between cerebral atrophy and the degree of dementia. In the present case, WS infarction caused by right internal carotid artery occlusion might be related to dementia and cerebral atrophy.

Migrainous stroke causing bilateral anterior cerebral artery territory infarction

A 38-year-old man developed bilateral anterior cerebral artery territory infarction during the course of a migraine. Magnetic resonance imaging showed bilateral ischemic lesions involving the cortex of the paramedian region of the frontal and parietal lobes, more prominent on the right. Cerebral angiography was normal. To our knowledge, this is the first report of bilateral anterior cerebral artery territory infarction from migraine.

[Homolateral ataxia and crural paresis following anterior cerebral artery territory infarction]

Homolateral ataxia and crural paresis (HACP) is defined as predominantly crural paresis with ipsilateral ataxia, a variant of ataxic hemiparesis (AH), by Fisher and his colleagues. HACP usually resulted from lacunar infarction in the basis pontis at the junction of the upper one-third and inferior two-third of the pons, or in the posterior limb of the internal capsule. We reported a patient with HACP which was caused by an infarct in the paracentral gyrus irrigated by the anterior cerebral artery (ACA). He had had no cerebellar signs before the onset of HACP, although he had old small infarcts in the right pons, right thalamus and left cerebellar hemisphere. Neuroimaging and other clinical studies suggested that the mechanism of the present infarction was the most-likely embolic, but not lacunar. As far as we know, there has been only one abstract presentation of a patient with HACP due to ACA territory infarction in Japan, although five such cases were recently reported by Bogousslavsky and others.