[Claude syndrome: Incomplete third cranial nerve palsy and contralateral ataxia]

Midbrain strokes are rare and are usually accompanied by other concomitant injuries. The simultaneous presence of ipsi and contralateral signs makes it necessary to think of a brainstem syndrome due to involvement of the brainstem. Magnetic nuclear resonance is the study of choice to characterize and locate the lesion. We report the case of a 71-year old man who presented right third cranial nerve palsy and hemiataxia, a rare condition known as Claude's syndrome.

Atypical "nine" syndrome in bilateral pontine infarction: A case report

RATIONALE

"Nine" syndrome, that is "eight-and-a-half" syndrome associated with hemiplegia and hemidysesthesia, is a rare disorder. This study aimed to report a Chinese patient with acute bilateral pontine infarction manifesting as eight-and-a-half syndrome plus hemiplegia (atypical nine syndrome), and also the clinical and neuroimaging findings were explained and discussed with review of the literature.

PATIENT CONCERNS

A 79-year-old woman experienced sudden vertigo, nausea, vomiting, and weakness at her left arm and leg. The neurological examination disclosed her right horizontal gaze palsy, internuclear ophtalmoplegia (INO), and right-sided peripheral facial paralysis combined with slight left-sided hemiplegia, which were consistent with atypical nine syndrome.

DIAGNOSES

Cranial magnetic resonance imaging (MRI) displayed acute multiple ischemic infarction, involving bilateral pontine tegmentum, basilar part of right paramedian pontine, and left cerebellar hemisphere. Intracranial MR angiography (MRA) revealed right middle cerebral artery occlusion, no clear visualization of bilateral vertebral arteries, and basilar artery hypoplasia with stenotic segments.

INTERVENTIONS

Thrombolysis could not be performed due to the time window. The patient was given low molecular weight heparin for anticoagulation because of posterior circulation and progressive stroke.

OUTCOMES

The vertigo disappeared, and a notable improvement with minimal restriction in the right horizontal gaze and partial relief of her facial paralysis were found at discharge, while her left hemiparesis was fully resolved. No recurrence of cerebral infarction was observed during follow-up as well.

LESSONS

This case report with atypical nine syndrome is fairly rare. Nine syndrome may refer to the lesion located in unilateral tegmentum of the caudal pontine plus paramedian pontine, with an important localization value.

Varicella zoster virus reactivation antedating ipsilateral brainstem stroke

itor Title: Varicella zoster virus reactivation antedating ipsilateral brainstem stroke Authors: Giuliana Galassi1, Maurilio Genovese2, Marisa Meacci3, Marcella Malagoli2 Affiliations: 1Department of Biomedical, Metabolic, Neural Sciences, University Hospital of Modena, Italy, 2Neuroradiology Service, University Hospital of Modena, Italy, 3Department of Laboratory Medicine and Patholgy, Microbiology and Virology Unit, University Hospital of Modena, Italy Corresponding Author: Giuliana Galassi, MD, Department of Biomedical, Metabolic, Neural Sciences, University Hospital of Modena, Via P. Giardini 1455, Modena, Italy, Tel: 39-3497325802, Email: giulianagalassi46@gmail.com Abstract: Varicella zoster virus (VZV) infection and reactivation are associated with a number of neurologic conditions. Unifocal large vessel infarcts may follow zoster in the trigeminal or cervical distribution as a result of transaxonal transport of virus from trigeminal or cervical afferent fibers that innervate vessels. Ophthalmic zoster (HZO) might cause ophthalmoplegic syndromes, with secondary optic neuritis. Mechanisms include local orbital muscle inflammation and, viral spread from the ophthalmic branch of the fifth nerve with associated vasculopathy. A 72-year-old man developed a vesicular rash in the territory of C5-T5-6. Within four weeks, the patient developed headache, dysphagia, left facial and extremity ataxic weakness. Magnetic resonance imaging (MRI) revealed a right pontine infarction. A 66-year-old woman presented with right-sided painfull HZO. One week later she developed complete external ophthalmoplegia and blurred vision. MRI showed ill-defined signal alteration in the retrobulbar tissue. Three weeks later, the patient was admitted because of dysarthria, deviated tongue, left-sided limb weakness, and tactile hypoesthesia. Spinal fluid contained 23 lymphocytes/mm3 and increased protein. The serum contained antibodies to VZV IgG and IgM in both cases. The patients received intravenously acyclovir with improvement. This report confirms unusual occurrence of ipsilateral brainstem stroke after VZV reactivation in immunocompetent subjects.

[Posterior fossa infarct misdiagnosed as acute peripheral vestibulopathy]

Patients with acute central vestibular syndrome (AVS) can mimic acute peripheral vestibulopathy, which can mislead to a diagnosis of posterior fossa infarcts. Delayed diagnosis will prevent relevant treatment and may lead to severe disability and in worst case death. Understanding of AVS is extremely relevant for physicians in hospital and prehospital care to insure the right treatment. I this case report of a 35-year-old male patient with AVS the correct diagnosis was made relatively late.

Pitfalls in the diagnosis of pupil-sparing oculomotor nerve palsy without limb ataxia: A case report of a variant of Claude's syndrome and neuroanatomical analysis using diffusion-tensor imaging

Midbrain infarction causing oculomotor nerve palsy with contralateral ataxia is named Claude's syndrome. Herein we report the case of a variant of Claude's syndrome, which shows pupil-sparing oculomotor nerve palsy without the accompanying neurological deficits other than subtle truncal ataxia. MRI and Diffusion Tensor Imaging revealed that midbrain infarction was located rostrally above the decussation of the superior cerebellar peduncle (SCP) and might have partially destructed the tectospinal tract, which resulted in the absence of limb ataxia and presence of subtle truncal ataxia. In this variant of Claude's syndrome, we should carefully assess truncal ataxia to avoid misdiagnosing it as isolated pupil-sparing oculomotor nerve palsy because the patient showed apparently normal gait and truncal ataxia was only revealed by unstable tandem gait.

Pupil-sparing third nerve palsies and hemiataxia: Claude's and reverse Claude's syndrome

We report two patients with midbrain infarction with pupil-sparing third nerve palsies and hemiataxia: one with contralateral ataxia (Claude's syndrome) and one with ipsilateral ataxia (which we refer to as reverse Claude's syndrome). We highlight the importance of a thorough neurologic evaluation with partial oculomotor palsies and describe, to our knowledge, the fourth account in the literature of a pupil-sparing third nerve palsy with ipsilateral cerebellar ataxia.

Claude's Syndrome without Ptosis Caused by a Midbrain Infarction

An 80-year-old man with angina pectoris abruptly developed Claude's syndrome, which consisted of left-sided partial oculomotor nerve palsy without ptosis and right-sided hemiataxia. There were no other neurological abnormalities. Cranial magnetic resonance imaging indicated an infarction of the left inferior paramedian mesencephalic artery, which may have involved the most caudal portion of the oculomotor fascicules. With anti-platelet therapy, the patient became asymptomatic within 10 days. The oculomotor fascicular arrangement in humans remains unclear. Our case suggests that in the oculomotor fascicles, the fibers to the levator palpebrae superioris may be located more in the rostral region than previously hypothesized.

Mapping affected territory of anterior/posterior inferior cerebellar artery infarction using a vestibular test battery

CONCLUSION

Although the affected territory in the posterior/anterior inferior cerebellar artery (PICA/AICA) infarction could not be meticulously demonstrated by magnetic resonance imaging (MRI), it could be picked up by the results of a vestibular test battery comprising caloric, ocular vestibular evoked myogenic potential (oVEMP), and cervical VEMP (cVEMP) tests.

OBJECTIVES

This study applied audiometry and caloric, oVEMP, and cVEMP tests to map affected territory in patients with PICA/AICA infarction.

METHODS

Fourteen patients, including 11 with PICA infarction and 3 with AICA infarction, were enrolled in this study during the last 8 years. Each patient underwent audiometry, caloric test, oVEMP test, and cVEMP test.

RESULTS

In the PICA group, 8 (36%) of 22 ears had a mean hearing level >25 dB. All six ears (100%) in the AICA group had abnormal hearing, and thus both groups revealed a significant difference. Conversely, significant differences were not observed in the vestibular test battery between the PICA and AICA groups. MRI demonstrated infarction at the brainstem for six patients, while one patient also had cerebellar involvement, indicated by loss of visual suppression on caloric nystagmus. Six patients showed infarction at the cerebellum, and four of them had brainstem affliction based on abnormal oVEMP/cVEMP test results.

Stroke syndromes and clinical management

The knowledge of brain syndromes is essential for stroke physicians and neurologists, particularly those that can be extremely difficult and challenging to diagnose due to the great variability of symptom presentation and yet of clinical significance in terms of potential devastating effect with poor outcome. The diagnosis and understanding of stroke syndromes has improved dramatically over the years with the advent of modern imaging, while the management is similar to general care as recommended by various guidelines in addition to care of such patients on specialized units with facilities for continuous monitoring of vital signs and dedicated stroke therapy. Such critical care can be provided either in the acute stroke unit, the medical intensive care unit or the neurological intensive care unit. There may be no definitive treatment at reversing stroke syndromes, but it is important to identify the signs and symptoms for an early diagnosis to prompt quick treatment, which can prevent further devastating complications following stroke. The aim of this article is to discuss some of the important clinical stroke syndromes encountered in clinical practice and discuss their management.

Brain stem infarction associated with familial Mediterranean fever and central nervous system vasculitis

Familial Mediterranean fever (FMF) is an autoinflammatory autosomal recessive disease caused by mutations of the Mediterranean fever (MEFV) gene on chromosome 16p. Clinically, it is characterized by recurrent episodes of fever and painful polyserositis. An association of FMF with systemic vasculitis, namely Henoch-Schönlein purpura, polyarteritis nodosa and Behçet's disease has been described. Neurological manifestations of FMF occur rarely and include demyelinating (MS-like) lesions, posterior reversible encephalopathy syndrome, and pseudotumour cerebri. Hitherto hardly known, we herein present a young patient with a genetically proven FMF who suffered a brain stem infarction during a typical FMF attack. After a careful diagnostic workup including cerebrospinal fluid analysis, intra-arterial angiography and leptomeningeal biopsy, a FMF-associated central nervous system vasculitis was identified as the cause of stroke. The pathophysiological background and potential therapeutic strategies are discussed.

Panmedullary edema with inferior olivary hypertrophy in bilateral medial medullary infarction

Bilateral medial medullary infarction (MMI) is a rare type of stroke with poor outcomes. Inferior olivary nucleus hypertrophy results from a pathologic lesion in the Guillain-Mollaret triangle. The relationship between inferior olivary nucleus hypertrophy and the medullary lesion is obscure. To the best of our knowledge, only 1 autopsy case with unilateral medial medullary infarction that was associated with ipsilateral inferior olivary nucleus hypertrophy has been reported. We describe a rare case with acute infarction in the bilateral medial medulla oblongata accompanied by subacute bilateral inferior olivary nucleus hypertrophy and panmedullary edema. The hypertrophy appeared to have been caused by local ischemic damage to the termination of the central tegmental tract at the bilateral inferior olivary nucleus.

Locked-in syndrome: a critical and time-dependent diagnosis

Locked-in syndrome (LIS) is the combination of quadriplegia and anarthria (inability to speak), with the preservation of consciousness. The majority of cases are caused by basilar artery occlusion leading to brainstem infarction in the ventral pons, yet numerous other etiologies have been described. The diagnosis of LIS is completely dependent on the physician's ability to know that these manifestations originate in the brainstem and the posterior circulation that supplies it. This knowledge hinges on the ability of the examining physician to conduct a rapid, yet appropriately thorough neurologic examination. With recent advances in interventional neuroradiology leading to improved patient outcomes, LIS has evolved into a critical, time-dependent diagnosis. Herein, we present the case of a male patient who initially presented to the emergency department of a community hospital with coma of unknown cause. By presenting this case and focusing on the importance of the occulomotor exam, we hope to help in the rapid identification and treatment of patients with LIS in the emergency room and avoid outcomes similar to that of our patient.

Recurrent brainstem lesions mimicking infarctions in an elderly patient with neuromyelitis optica spectrum disorder

Anti-aquaporin-4 (AQP4) antibody is highly specific for neuromyelitis optica (NMO) and NMO spectrum disorder. Brainstem lesions sometimes show involvement in NMO and NMO spectrum disorder, and onset is usually diagnosed in young or middle-aged adults. Here, we report the case of an 87-year-old woman with recurrent brainstem lesions and subsequent severe longitudinally extensive cervical cord lesions who was found to be positive for anti-AQP4 antibody. In patients with recurrent brainstem lesions, even in the elderly and those with symptoms mimicking infarction, NMO spectrum disorder should be considered as a differential diagnosis.

[Dysphagia in Avellis' syndrome]

BACKGROUND

Avellis' syndrome (lateral medulla oblongata ischaemia) is a rare neurological disorder. Early recognition of brain stem infarction may prevent referral to specialists other than a neurologist.

CASE DESCRIPTION

A 53-year-old woman was initially presented to an internist with acute onset of headache, dysphagia, nausea and vomiting. She was also hoarse and had a tingling feeling on the left side of her face, and in her left arm and leg. A neurologist was consulted and diagnosed Avellis' syndrome. MRI of the brain revealed ischaemia in the lateral medulla oblongata on the right side.

CONCLUSION

Brain stem infarction may be hard to recognize as lateralization is often less predominant than in hemispheric syndromes. In acute onset of dysphagia, the differential diagnosis should always include brain stem infarction.

Locked-in syndrome as an unusual complication of acute otitis media

BACKGROUND

A 32-year-old woman developed altered consciousness two days after initial symptoms of acute otitis media, with purulent discharge from the right ear. She was quadriplegic, with spontaneous eye opening, mild neck stiffness, and lacking vestibular-ocular reflexes.

METHODOLOGY

Upon admission, the patient was subjected to brain computed tomography (CT), magnetic resonance imaging (MRI), and lumbar puncture.

RESULTS

CT was consistent with pansinusitis, right middle ear otitis, mastoiditis, and sphenoiditis. No brainstem lesion was evident; brain MRI demonstrated ischemic and secondary hemorrhagic lesions in the pons and cerebral peduncles. The dura mater in the petroclival space was intensely inflamed, and likely responsible for reduced basilar arterial blood flow. Lumbar puncture yielded clear cerebrospinal fluid; gram stain examination was negative and culture remained sterile. Streptococcus pneumoniae and Haemophilus influenzae were cultured from the purulent ear discharge.

CONCLUSION

The final diagnosis was locked-in syndrome consecutive to inflammatory changes compressing the basilar artery.

[An evaluation of clinical characteristics and prognosis of brain-stem infarction in diabetics]

OBJECTIVE

To analyze the relationship between diabetics and the onset, clinical outcomes and prognosis of brainstem infarction, and to evaluate the impact of diabetes on brainstem infarction.

METHOD

Compare 172 cases of acute brainstem infarction in patients with or without diabetes. Analyze the associated risk factors of patients with brain-stem infarction in diabetics by multi-variate logistic regression analysis. Compare the National Institutes of Health Stroke Scale (NIHSS) and Modified Rankin scale (mRS) Score, pathogenetic condition and the outcome of the two groups in different times.

RESULTS

The systolic blood pressure (SBP), TG, LDL-C, apolipoprotein B (Apo B), glutamyl transpeptidase (γ-GT), fibrinogen (Fb), fasting blood glucose (FPG) and glycosylated hemoglobin(HbA1c)in diabetic group were higher than those in non-diabetic group, which was statistically significant (P < 0.05). From multi-variate logistic regression analysis, γ-GT, Apo B and FPG were the risk predictors of diabetes with brainstem infarction(OR = 1.017, 4.667 and 3.173, respectively), while HDL-C was protective (OR = 0.288). HbA1c was a risk predictor of severity for acute brainstem infarction (OR = 1.299), while Apo A was beneficial (OR = 0.212). Compared with brain-stem infarction in non-diabetic group, NIHSS score and intensive care therapy of diabetic groups on the admission had no statistically significance, while the NIHSS score on discharge and the outcome at 6 months' of follow-up were statistically significant.

CONCLUSIONS

Diabetes is closely associated with brainstem infarction. Brainstem infarction with diabetes cause more rapid progression, poorer prognosis, higher rates of mortality as well as disability and higher recurrence rate of cerebral infarction.

Top of the basilar syndrome in a young adult initially presenting with a convulsive seizure

A 23-year-old man was admitted to our hospital due to loss of consciousness and a generalized convulsive seizure. He was diagnosed as having primary epilepsy and treated with antiepileptic drugs. Emergency CT scan of the head showed no abnormality. However, MRI scan of the head several days after admission revealed fresh infarctions caused by occlusion of the basilar artery, i.e., "top of the basilar" syndrome. This case indicates the need for precise differential diagnosis of convulsive seizure in an emergency situation. It should also be borne in mind that basilar occlusion with 'onset seizure' can occur even in young adults who have no risk factors for stroke.

Trigemino-autonomic headache related to Gasperini syndrome

We report the association of ipsilateral trigemino-autonomic headache to a case of right-sided nuclear facial and abducens palsy (Gasperini syndrome), ipsilateral hypacusis and right hemiataxia, caused by the occlusion of the right anterior inferior cerebellar artery. Short-lasting attacks of mild to moderate ipsilateral fronto-periorbital head pain, accompanied by lacrimation and mild conjunctival injection during more severe attacks, were present from the onset of symptoms, with a gradual worsening over the next few months and remitting during naproxen therapy. Magnetic resonance imaging showed an infarct in the right cerebellar peduncle, extending toward the pontine tegmentum, also involving the ipsilateral spinal trigeminal nucleus and tract and the trigeminal entry zone. Gasperini syndrome may be accompanied by ipsilateral trigemino-autonomic head pain.

Claude's syndrome associated with neurocysticercosis

Claude's syndrome is a distinctive brainstem syndrome characterized by ipsilateral third cranial nerve palsy with contralateral hemiataxia and is due to an intrinsic or extrinsic lesion in the midbrain. We report a case of Claude's syndrome caused by neurocysticercosis infection. A 68 year-old Asian man was admitted to our hospital because of ataxia, left ptosis, and diplopia. Brain magnetic resonance imaging (MRI) showed a cystic lesion in the midbrain, which was surrounded by ring enhancement and peripheral edema. Neurocysticercosis infection was diagnosed by the cerebral spinal fluid study. The patient was treated with albendazole and steroids. A follow-up brain MRI three months later demonstrated the disappearance of a surrounding brain edema and rim enhancement. The most common cause of Claude's syndrome is cerebrovascular disease and malignancy. However, there is no report caused by neurocysticercosis infection. Therefore, if we encounter Claude's syndrome, we should consider neurocysticercosis infection as one of the etiologic factors.

A case of myxedema coma presenting as a brain stem infarct in a 74-year-old Korean woman

Myxedema coma is the extreme form of untreated hypothyroidism. In reality, few patients present comatose with severe myxedema. We describe a patient with myxedema coma which was initially misdiagnosed as a brain stem infarct. She presented to the hospital with alteration of the mental status, generalized edema, hypothermia, hypoventilation, and hypotension. Initially her brain stem reflexes were absent. After respiratory and circulatory support, her neurologic status was not improved soon. The diagnosis of myxedema coma was often missed or delayed due to various clinical findings and concomitant medical condition and precipitating factors. It is more difficult to diagnose when a patient has no medical history of hypothyroidism. A high index of clinical suspicion can make a timely diagnosis and initiate appropriate treatment. We report this case to alert clinicians considering diagnosis of myxedema coma in patients with severe decompensated metabolic state including mental change.

The prevalence of thyrotoxicosis-related seizures

BACKGROUND

Central nervous system dysfunction, such as hyperexcitation, irritability, and disturbance of consciousness, may occur in patients with thyrotoxicosis. There are also a few case reports of seizures attributed to thyrotoxicosis. The objective of the present study was to determine the prevalence of seizures that appeared to be related to the thyrotoxic state in patients with thyrotoxicosis.

METHODS

We retrospectively determined the prevalence and clinical features of seizures in 3382 patients with hyperthyroidism. Among patients with seizures, we excluded those with other causes of seizures or a history of epilepsy. We did not exclude two patients in whom later work-up showed an abnormal magnetic resonance imaging, as their seizures resolved after they became euthyroid.

RESULTS

Among the 3382 patients with hyperthyroidism, there were seven patients (0.2%) with seizures who met our criteria. Primary generalized tonic-clonic seizures occurred in four patients (57%), complex partial seizures with secondary generalized tonic-clonic seizures occurred in two patients (29%), and one patient had a focal seizure (14%). The initial electroencephalography (EEG) was normal in two patients (29%), had generalized slow activity in four patients (57%), and had diffuse generalized beta activity in one patient (14%). On magnetic resonance imaging, one patient had diffuse brain atrophy, and one had an old basal ganglia infarct. After the patients became euthyroid, the EEG was repeated and was normal in all patients. During follow-up periods ranging from 18 to 24 months, none of the patients had seizures.

CONCLUSIONS

Hyperthyroidism is the precipitating cause of seizures in a small percentage of these patients. In these patients, the prognosis is good if they become euthyroid. The prevalence of thyrotoxicosis-related seizures reported here can be used in conjunction with the prevalence of thyrotoxicosis in the population to estimate the prevalence of thyrotoxicosis-related seizures in populations.

Lateral medullary infarction presenting as Brown-Séquard syndrome-like manifestation: a case report and literature review

PURPOSE

Lateral medullary infarction is not uncommon in clinical practice of neurology. This report describes a patient who initially presented with Brown-Séquard syndrome-like manifestation but was later diagnosed with acute infarction in the left lower lateral medulla.

CASE REPORT

A 65-year-old woman presented with acute onset of unsteadiness, left side hemiparesis, left limb dysmetria, left side partial Horner syndrome, and paresthesia in the right lower limb and trunk with a sensory level at T5 on the right. No bulbar symptoms nor facial paresthesia was noted. Brown- Séquard syndrome was suspected initially, but cervical spine magnetic resonance imaging showed only mild spinal stenosis. Brain magnetic resonance imaging revealed acute infarction in the left lower lateral medulla. The mechanism of this unusual presentation is discussed.

CONCLUSION

Brown-Séquard syndrome-like manifestation can be a rare presentation of lower lateral medullary infarction.

Stuttering after right cerebellar infarction: a case study

We report a male patient with neurogenic stuttering after cerebellar infarction. He had suffered from frontal and thalamus damage and he had exhibited aphasia, but his speech had been fluent until onset of the cerebellar infarction. Results of analysis of speech samples included the following: (1) the patient showed very frequent syllable repetition and part-word repetition. (2) The stuttering occurrence rate at the second test was much higher than at the first test. (3) Almost all stuttering occurred on initial word sounds; stuttering on the medial and final word was less frequent. (4) Adaptation effect was absent. (5) Secondary behaviors such as closing of the eyes and grimacing were observed. The internal model related to cerebellar functions can be modified using feedback-error information. Results suggest that internal model dysfunction caused this patient's stuttering.

EDUCATIONAL OBJECTIVES

After reading this text, the reader will be able to: (1) provide characteristics of neurogenic stuttering after the cerebellum infarction; (2) discuss the relationship between neurogenic stuttering and functions of the cerebellum.

Isolated vestibular nucleus infarction mimicking acute peripheral vestibulopathy

BACKGROUND AND PURPOSE

Although several articles have been published on central vestibular syndrome mimicking acute peripheral vestibulopathy (ie, pseudo-acute peripheral vestibulopathy), there are no reports of a brainstem infarct that selectively involves the vestibular nucleus and causes isolated vertigo.

SUMMARY OF CASE

We report a patient with an isolated vestibular nucleus infarction who presented with isolated prolonged vertigo, spontaneous horizontal nystagmus with a torsional component, a positive head impulse test result, and unilateral canal paresis to caloric stimulation.

CONCLUSIONS

This is the first report of pseudo-acute peripheral vestibulopathy associated with isolated vestibular nucleus infarction. Isolated vestibular nucleus infarction should be considered in the differential diagnosis of central vascular vertigo syndrome, especially when the patient has unilateral canal paresis but without other neurologic symptoms or signs.

Occult traumatic dissection of vertebral artery with an excellent outcome

We present the case of a young male with severe head injury, cervico-thoracic fractures, and an initially unrecognized brainstem infarct due to unilateral dissection of vertebral artery, who made an unusually excellent recovery. This report stresses the importance of prompt clinico-imaging diagnosis and prophylactic anticoagulant treatment in such cases.

An unusual cause of fixed dilated pupils after cardiac surgery

BACKGROUND

The presence of fixed, dilated pupils after cardiac surgery is an ominous sign, typically indicating severe diffuse hypoxic-ischemic brain injury. Rarely, however, this finding can be seen as a result of focal midbrain ischemia. It is important to differentiate between these syndromes, as the latter might be amenable to acute stroke treatments, and because they affect consciousness very differently.

CASE

A 46-year-old man with diffuse atherosclerosis underwent coronary artery bypass grafting and closure of an incidentally discovered patent foramen ovale. He underwent neurologic evaluation on post-operative day 6 because he was not speaking and appeared to have a new right hemiparesis. Eye movements, pupillary, and lid function were all normal at this time. MRI showed multiple posterior circulation infarcts, involving both cerebral peduncles. On post-operative day 12, he became unresponsive, quadriplegic, and had bilaterally fixed, dilated pupils. CT showed low attenuation in nearly the entirety of both cerebral peduncles.

DISCUSSION

Midbrain infarction is rare. Bilateral midbrain infarction is even rarer and typically presents as locked-in syndrome with preservation of pupillary function and at least vertical eye movements. In our review of the literature, we found only three other cases of midbrain infarction associated with bilateral mydriasis. As in our case, these characteristically involved the anteromedial midbrain bilaterally.

CONCLUSIONS

Fixed, dilated pupils after cardiac surgery can rarely be caused by bilateral anteromedial midbrain infarctions. It is important to differentiate this from the much more common diffuse hypoxic-ischemic injury.

Painless aortic dissection masquerading as brainstem stroke with catastrophic anticoagulant use

Painless aortic dissection with only focal neurological symptoms and signs can be a great challenge to the emergency physician. Inadvertently and erroneous treatment of stroke may threaten patient's life. We present a patient with painless aortic dissection (DeBakey I), which was initially misdiagnosed as brainstem stroke with catastrophic anticoagulant use. Finally, the patient died of multiorgan failure after surgical intervention.

Time course of diffusion imaging in acute brainstem infarcts

PURPOSE

To study the time course of diffusion imaging at the lesion site in brainstem infarcts.

MATERIALS AND METHODS

Sequential MR scans were acquired from 24 patients with brainstem infarcts. Diffusion-weighted images (DWI), T(2)-weighted images (T(2)w), maps of apparent diffusion coefficient, and maps of fractional anisotropy were generated from each MR scan. A trend function was fitted to these measurements to model an objective, general time course of the studied parameters.

RESULTS

Apparent diffusion coefficient (ADC) continuously decreased over time until a transition time around 45 hours; afterwards a continuous increase took place. After the 14th day ADC reached values similar to the ADC of the intact contralateral side (pseudonormalization) and then further increased. Fractional anisotropy (FA) decreased continuously over 3 to 6 months.

CONCLUSION

Times of transition and pseudonormalization of ADC were longer than described for territorial hemispheric infarcts and describe the acute to subacute phase of brainstem ischemia. In contrast, the continuous decline of FA over 3 to 6 months indicates a chronic process of change of histological structures in brainstem ischemia, and may be regarded as an indicator of the chronic phase.

[Type I neurofibromatosis and megadolichobasilar artery]

Intracranial vascular malformations are rare but tend to appear more frequently than usual in patients with type I neurofibromatosis (NFI). Aneurysms of the basilar artery have been described four times so far. We report two cases of 51- and 62-year-old patients with type I neurofibromatosis who showed long fusiform dilation of the basilar artery. Clinically both patients presented with locked-in syndrome and died 15 and 11 days after admission. The diagnosis was confirmed by autopsy. These are the first published cases of locked-in syndrome following thrombosis of a megadolichobasilar artery in association with neurofibromatosis I. Our results show that cerebral vascular malformations are found more frequently than random chance would predict in patients with NF I.

The rehabilitation of patients recovering from brainstem strokes: case studies and clinical considerations

An estimated 15% of all patients admitted to stroke rehabilitation units experience a brainstem stroke. Two case studies are presented to illustrate some of the difficulties encountered in the rehabilitation of these individuals. Unlike hemispheric stroke, the characteristic consequences of brainstem stroke include ataxia, dysarthria, and diplopia. Additionally, individuals with brainstem stroke may suffer from severe dysphagia and may require enteral feedings. Unlike the rehabilitation of patients with hemispheric stroke, where there is an impressive and relatively comprehensive research literature, there has been surprisingly little research published on the rehabilitation of patients with brainstem stroke despite the fact they represent a significant number of patients admitted to stroke rehabilitation units.

Retroperitoneal infection complicated by bacterial meningitis and ventriculitis with secondary brainstem infarction

INTRODUCTION

Retroperitoneal abscesses have been previously reported to cause infectious meningitis. Cerebral infarction is a known complication of basilar meningitis.

SUMMARY OF CASE

We present a case where a comatose patient with a known retroperitoneal abscess was diagnosed via Magnetic Resonance Imaging (MRI) with extensive brainstem infarction secondary to basilar meningitis.

A case of bilateral medial medullary infarction presenting with "heart appearance" sign

Bilateral medial medullary infarction (bilateral MMI) is an extremely rare cerebrovascular accident presenting with quadriplegia as the initial symptom and resulting in poor functional prognosis. Diagnosis of bilateral MMI has become possible based on brain MRI findings in recent years, but is still very difficult to diagnose. In the present case, brain MRI was performed 9 hours after the onset, and the infarcted area was detected only by diffusion-weighted MRI. However, changes over time were clearly detected by FLAIR-MRI on days 3, 5 and 7, but it is essential to confirm the disease by DW-MRI in the early stage.The infarct observed on horizontal MRI sections showed the characteristic "heart appearance" sign. For an early diagnosis of bilateral MMI, it is essential to bear in mind that characteristic findings may be obtained by diffusion-weighted MRI.

"Salt and pepper" in the eye and face: a prelude to brainstem ischemia

PURPOSE

To report the "salt and pepper"(SP) eye pain as a herald symptom of pontine ischemia.

DESIGN

Observational case series.

METHODS

We reviewed clinical and neuroimaging findings of four patients who presented initially with the sensation of SP in the eyes and then developed paramedian pontine infarcts confirmed by neuroimaging.

RESULTS

All of the patients developed other neurologic symptoms or signs, either in association with the sensation of SP in the eyes, from hours to days later. Magnetic resonance imaging (MRI) showed paramedian pontine infarcts in all of the patients and angiography showed basilar artery occlusive disease in three of them.

CONCLUSION

Impending pontine ischemia is an important differential diagnosis in patients with acute ocular pain. Prompt neurovascular evaluation and treatment may avoid devastating brainstem infarcts that cause death or long-term disability, particularly in patients with basilar artery occlusive disease.

Surgical and endovascular management of symptomatic posterior circulation fusiform aneurysms

Object

Patients with fusiform aneurysms can present with subarachnoid hemorrhage (SAH), mass effect, ischemia, or unrelated symptoms. The absence of an aneurysm neck impedes the direct application of a clip and endovascular coil deployment. To evaluate the effects of their treatments, the authors retrospectively analyzed a consecutive series of patients with posterior circulation fusiform aneurysms treated at Stanford University Medical Center between 1991 and 2005.

Methods

Forty-nine patients (mean age 53 years, male/female ratio 1.2:1) treated at the authors' medical center form the basis of the analysis. Twenty-nine patients presented with an SAH. The patients presenting without SAH had cranial nerve dysfunction (five patients), symptoms of mass effect (eight patients), ischemia (six patients), or unrelated symptoms (one patient). The aneurysms were located on the vertebral artery (VA) or posterior inferior cerebellar artery (PICA) (21 patients); vertebrobasilar junction (VBJ) or basilar artery (BA) (18 patients); and posterior cerebral artery (PCA) (10 patients). Pretreatment clinical grades were determined using the Hunt and Hess scale; for patients with un-ruptured aneurysms (Hunt and Hess Grade 0) functional subgrades were added. Outcome was evaluated using the Glasgow Outcome Scale (GOS) score during a mean follow-up period of 33 months.

Overall long-term outcome was good (GOS Score 4 or 5) in 59%, poor (GOS Score 2 or 3) in 16%, and fatal (GOS Score 1) in 24% of the patients. In a univariate analysis, poor outcome was predicted by age greater than 55 years, VBJ location, pretreatment Hunt and Hess grade in patients presenting with SAH, and incomplete aneurysm thrombosis after endovascular treatment. In a multivariate analysis, age greater than 55 years was the confounding factor predicting poor outcome. Stratification by aneurysm location removed the effect of age. Of 13 patients with residual aneurysm after treatment, five (38%) subsequently died of SAH (three patients) or progressive mass effect/brainstem ischemia (two patients).

Conclusions

Certain posterior circulation aneurysm locations (PCA, VA–PICA, and BA–VBJ) represent separate disease entities affecting patients at different ages with distinct patterns of presentation, treatment options, and outcomes. Favorable overall long-term outcome can be achieved in 90% of patients with PCA aneurysms, in 60% of those with VA–PICA aneurysms, and in 39% of those with BA–VBJ aneurysms when using endovascular and surgical techniques. The natural history of the disease was poor in patients with incomplete aneurysm thrombosis after treatment.

Cerebellar and brainstem infarction as a complication of CT-guided transforaminal cervical nerve root block

A 60-year-old man with a 4-year history of intractable neck pain and radicular pain in the C5 nerve root distribution presented to our department for a CT-guided transforaminal left C5 nerve root block. He had had a similar procedure on the right 2 months previously, and had significant improvement of his symptoms with considerable pain relief. On this occasion he was again accepted for the procedure after the risks and potential complications had been explained. Under CT guidance, a 25G spinal needle was introduced and after confirmation of the position of the needle, steroid was injected. Immediately the patient became unresponsive, and later developed a MR-proven infarct affecting the left vertebral artery (VA) territory. This is the first report of a major complication of a cervical root injection under CT guidance reported in the literature. We present this case report and the literature review of the potential complications of this procedure.