Author(s): Vishwaprem Raj D. R1, Srinivasa Babu C. R2
BACKGROUND AND PURPOSE
Posterior Reversible Encephalopathy Syndrome (PRES) is a neurotoxic state that occurs secondary to the inability of posterior circulation to autoregulate. The clinical spectrum and the underlying pathophysiology are still poorly defined. No conclusive evidence has been put forward regarding the relationship between clinical conditions and specific imaging findings of severity or location of oedema.
To assess the role of computed tomography in evaluation of Posterior Reversible Encephalopathy Syndrome.
MATERIALS AND METHODS
55 patients referred to the Department of Radio-Diagnosis, with a history of neurological abnormalities, including altered mental function, visual loss, stupor with a predisposing history favouring PRES and followed up for a period of 10 – 30 days.
21 patients (38.2%) were females. 32 patients (58.1%) were in the age group between 21 to 30 years. Predisposing condition; 16 (29.1%) presented with pre-eclampsia, 12 (21.8%) with post-partum status in altered sensorium, 9 (16.4%) with seizures, 7 (12.7%) with hypertension, 6 (10.9%) with visual disturbances, 4 (7.3%) with eclampsia and 1 (1.8%) with uraemia.
20 cases (36.4%) showed findings suggestive of posterior reversible encephalopathy syndrome on initial computed tomography examination. 35 cases showed no initial radiological evidence suggestive of posterior reversible encephalopathy syndrome. Of the 20 cases which showed computed tomographic evidence of posterior reversible encephalopathy syndrome, recovery was noted in 5 cases (9.1%). Persistence of findings detected on first CT was noted in 13 patients (23.6%).
Regional predominance of the lesions was as follows. Frontal lobe (39%), Parietal lobe (32%), Temporal lobe (15%) and occipital lobe (15%).
Varied clinical manifestations are associated with anatomical findings recognisable by neuro-imaging as PRES. Prompt imaging is necessary for the recognition of the condition and appropriate therapy should be initiated as early as possible for better patient outcome. Further studies regarding this condition are needed to clearly identify clinical and neuro-radiologic correlates in patients with signs of PRES at the time of presentation and their long-term neurologic outcomes.