Spinal cord involvement during hypertensive encephalopathy: clinical and radiological findings

Convergence-Retraction Nystagmus in a Dog With Presumptive Ischemic Encephalopathy Following Acute Cervicothoracic Myelopathy

A 6.5-year-old male neutered Trailhound was admitted for hyperacute, nonprogressive, left-sided hemiparesis. Physical and neurologic examination revealed nonpainful, left-sided poorly ambulatory hemiparesis, decreased left-sided postural reactions and thoracic limbs hyporeflexia. Neuroanatomic localisation was consistent with a left-sided C6-T2 myelopathy. Haematology and biochemistry revealed nonspecific abnormalities. Magnetic resonance imaging of the neck revealed a focal intramedullary lesion at the level of C6-C7 vertebrae compatible with acute hydrated noncompressive nucleus pulposus extrusion or ischemic myelopathy. During the second day of hospitalization, the dog developed convergence-retraction nystagmus, up-gaze palsy and eyelid retraction (Collier's sign) compatible with dorsal midbrain syndrome. Magnetic resonance imaging of the brain revealed a focal lesion compatible with dorsal midbrain ischemic infarct. Further clinicopathologic testing, thoracic and abdominal imaging were unremarkable. Ischemic encephalopathy of unknown etiology was additionally diagnosed. Physiotherapy was performed therapeutically. At 1-year follow-up the dog was normal. This is an unusual report of a dog with myelopathy followed by ischemic encephalopathy with manifestation of convergence-retraction nystagmus in the absence of vestibular signs. This saccadic intrusion is a characteristic clinical manifestation of a dorsal midbrain syndrome localization. The importance of a complete differential diagnoses list formation in a dog with ischemic encephalopathy which leads to a thorough diagnostic investigation plan is highlighted. Moreover, this report contributes to the enrichment of the clinical reasoning veterinary literature on convergence-retraction nystagmus. To the authors' knowledge, this is the second case report (fourth dog) to describe convergence-retraction nystagmus in dogs as a manifestation of dorsal midbrain syndrome.

Posterior reversible encephalopathy syndrome with spinal cord involvement but without hemisphere lesions: A case report

RATIONALE

Posterior reversible encephalopathy syndrome (PRES) was termed by Hinchey in 1996. Patients have a reversible vasogenic brain edema in imaging and acute neurological symptoms such as headache, seizures, encephalopathy, and visual disturbances when suffering from hypertension, pre-eclampsia/eclampsia, renal failure, immunosuppressive medications, autoimmune disorders, sepsis, thrombocytopaenia, hypocalcaemia, alcohol withdrawal, and many other potential causes. de Havenon A et al have proposed a new syndrome named PRES with spinal cord involvement (PRES-SCI). The patients with PRES-SCI have similar symptoms these of PRES. Patients have neurologic signs with the spinal cord involved and lesions in magnetic resonance imaging (MRI) extending to the cervicomedullary junction, usually with extreme elevation in blood pressure and a history of hypertensive retinopathy. We administrated a young patient whose condition was consistent with PRES-SCI except for the hemisphere lesions.

PATIENT CONCERNS

A 20-year-old Asian male patient was admitted for a 1 week history of blurred vision and weakness of the limbs. He has had poorly controlled hypertension for 1 year before admission. In emergency room, his blood pressure could raise to 260/140mmHg. Neurological examinations and cerebral spinal fluid tests were negative. The MRI of the brain and spinal cord showed reversible lesions in the medulla and upper cervical spinal cord that extended to the lower thoracic spine.

DIAGNOSIS

Taking into account the characteristic lesions in the MRI as well as the reversible course upon treatment, he was diagnosed PRES-SCI.

INTERVENTIONS

He was treated with medicines for the hypertension.

OUTCOMES

His symptoms rapidly improved and finally the lesions on the MRI of the brain and spianl cord disappeared.

LESSONS

Clinicians should suspect PRES-SCI when patients have mild or no neurologic signs accompanied with extreme elevation in blood pressure and lesions in spinal cord. Spinal lesions alone may be a subtype of PRES-SCI.

Posterior Reversible Encephalopathy Syndrome With Spinal Cord Involvement in Children

We characterized a cohort of patients with posterior reversible encephalopathy syndrome with spinal cord involvement. We encountered 2 children and identified an additional 19 patients from the internet databases. Of the 21 patients analyzed, 8 were children. The mean peak systolic blood pressure in adults was significantly higher than in children (221.8 ± 14.3 vs 191.4 ± 31.3 mm Hg; P < .01). Regardless of age, the most common clinical symptom was headache (90%) and the least common clinical symptom was seizures (28%). Atypical neuroimaging was more common in children (63%) than in adults (8%). Abnormal cerebrospinal fluid results were frequently found in children (83%). All children recovered uneventfully, but 3 adults had sequelae. A broader clinicoradiologic spectrum makes the diagnosis of children more complex than in adults. Awareness of the atypical features with a meticulous management of hypertension is imperative to avoid unnecessary invasive workups and to achieve an uneventful recovery.

Posterior reversible leukoencephalopathy syndrome with spinal cord involvement in a 9-year-old girl

We report the youngest pediatric case of posterior reversible leukoencephalopathy syndrome confined to brainstem and spinal cord. At presentation bicytopenia, renal derangement, visual disturbances, magnetic resonance imaging findings, increased protein content, IgG index and cell count in the cerebrospinal fluid led us to extensive search for myelitis. She received a short course of steroid treatment. The final diagnosis was hypertension due to reflux nephropathy. Severe hypertension that exceeds the range of autoregulation in anterior spinal territory may result in spinal posterior reversible leukoencephalopathy syndrome. Clinicians should be aware of spinal posterior reversible leukoencephalopathy syndrome when cases have extensive lesions in the brainstem and spinal cord with none or minimal clinical findings, so called "clinical radiologic dissociation".

Posterior reversible encephalopathy syndrome: clinical and radiological manifestations, pathophysiology, and outstanding questions

Almost two decades have elapsed since posterior reversible encephalopathy syndrome (PRES) was described in an influential case series. This usually reversible clinical syndrome is becoming increasingly recognised, in large part because of improved and more readily available brain imaging. Although the pathophysiological changes underlying PRES are not fully understood, endothelial dysfunction is a key factor. A diagnosis of PRES should be considered in the setting of acute neurological symptoms in patients with renal failure, blood pressure fluctuations, use of cytotoxic drugs, autoimmune disorders, or eclampsia. Characteristic radiographic findings include bilateral regions of subcortical vasogenic oedema that resolve within days or weeks. The presence of haemorrhage, restricted diffusion, contrast enhancement, and vasoconstriction are all compatible with a diagnosis. In most cases, PRES resolves spontaneously and patients show both clinical and radiological improvements. The range of symptoms that can comprise the syndrome might be broader than usually thought. In its mild form, this disorder might cause only one clinical symptom (headache or seizure) and radiographically might show few areas of vasogenic oedema or even normal brain imaging in some rare cases. In severe forms, PRES might cause substantial morbidity and even mortality, most often as a result of acute haemorrhage or massive posterior fossa oedema causing obstructive hydrocephalus or brainstem compression.

Posterior reversible encephalopathy syndrome

Posterior reversible encephalopathy syndrome (PRES) is a recently proposed cliniconeuroradiologic entity with several well-known causes, such as hypertensive encephalopathy, eclampsia, and the use of cytotoxic and immunosuppressive drugs, as well as some causes more recently described. PRES is characterized by neuroimaging findings of reversible vasogenic subcortical edema without infarction. The pathogenesis is incompletely understood. Two opposing hypotheses are commonly cited, but the issue is controversial: (1) the current more popular theory suggests that severe hypertension exceeds the limits of autoregulation, leading to breakthrough brain edema; (2) the earlier original theory suggests that hypertension leads to cerebral autoregulatory vasoconstriction, ischemia, and subsequent brain edema. The clinical syndrome of PRES typically involves headache, encephalopathy, visual symptoms, and seizures. The clinical presentation is often nonspecific, and therefore the diagnosis of PRES has come to increasingly rely on magnetic resonance imaging (MRI) abnormalities consistent with PRES with documented recovery clinically and on repeated neuroimaging. The diagnosis has important therapeutic and prognostic implications because the reversibility of the clinical and radiologic abnormalities is contingent on the prompt control of blood pressure and/or discontinuing the offending drug.

A case of hypertensive encephalopathy with extensive spinal lesions on MRI

A 14-year-old female had repeated vomiting, headache, abdominal pain, visual field deficit and lethargy at the onset of hypertensive encephalopathy. Cerebrospinal fluid (CSF) test revealed a high level of IgG and protein. MRI demonstrated no supratentorial cerebral lesions but hyperintense lesions were observed from the lower pons to the Th8 level of spinal cord and cerebellar cortex on T2 weighted and FLAIR images without contrast enhancement. The two antihypertensive drugs stabilized to control her blood pressure and improved her clinical symptoms. Reexamination of MRI and cerebrospinal fluid test also revealed clear improvement of the above abnormalities. The abnormal findings on abdominal CT and renography led us to suspect renal infarction. Abdominal angiography demonstrated multifocal stenoses of renal interlobar arteries, which were supposed to supply the renal infarcted regions. These suggested that the renal infarctions due to fibromuscular dysplasia caused systemic hypertension. There have been only two reports that demonstrated spinal cord lesions in reversible posterior leukoencephalopathy syndrome (RPLES). We report extensive spinal lesions on MRI and a high level of IgG in CSF at the subacute phase in a young female with RPLES associated with hypertensive (brainstem) encephalopathy.

Posterior reversible encephalopathy syndrome

PURPOSE OF REVIEW

The ophthalmologist may be called upon to evaluate visual loss in a patient with posterior reversible encephalopathy syndrome. Familiarity with presentation and clinical management is imperative, as visual loss is often reversible with prompt treatment directed at causative factors.

RECENT FINDINGS

Since its initial description in 1996, the predisposing factors, clinical presentation and radiographic variation of posterior reversible encephalopathy syndrome continue to expand. Case reports of newly uncovered associations of the syndrome appear frequently. Originally considered a subcortical disease of the posterior cerebrum, posterior reversible encephalopathy syndrome has been shown to affect gray matter and can involve both the anterior and posterior cortex, brainstem, cerebellum or even the spinal cord. The pathophysiologic basis of cerebral edema and molecular mechanisms of edema underlying the syndrome are currently being revealed.

SUMMARY

Acute hypertension, eclampsia, immunosuppressive medication, infection or autoimmune diseases can all result in the clinical syndrome of vasogenic edema in the central nervous system leading to headache, seizure, confusion and frequent visual loss. The biologic basis for the syndrome is likely an insult to cerebral vascular autoregulation. MRI is essential in diagnosing a cerebral cause for visual loss. The ophthalmologist may have the initial opportunity to diagnose the syndrome. Treatment may reverse clinical deficits, and is based on eliminating the etiologic causation.