According to the over-regulation conception, brain vessels spasm in response to acute hypertension, which results in cerebral ischemia and cytotoxic edema. According to the autoregulation breakthrough conception, cerebral arterioles are forced to dilate, leading to vasogenic edema.Cerebral edema can be generalized or focal. Brain ventricles are compressed, cortical gyri flattened. Diagnosis
Diagnostic methods for hypertensive encephalopathy include physical examination, blood pressure measurement, blood sampling, ECG, EEG, chest X-ray, urinalysis, arterial blood gas analysis, and imaging of the head (CAT scan and/or MRI). Since decreasing blood pressure is essential, anti-hypertensive medication is administered without awaiting the results of the laboratory tests. Electroencephalographic examination detects the absence of alpha waves, signifying impaired consciousness. In people with visual disturbances, slow waves are detected in the occipital areas. Treatment
The initial aim of treatment in hypertensive crises is to rapidly lower the diastolic pressure to about 100 to 105 mmHg; this goal should be achieved within two to six hours, with the maximum initial fall in BP not exceeding 25 percent of the presenting value. This level of BP control will allow gradual healing of the necrotizing vascular lesions. More aggressive hypotensive therapy is both unnecessary and may reduce the blood pressure below the autoregulatory range, possibly leading to ischemic events (such as stroke or coronary disease).Once the BP is controlled, the person should be switched to medication by mouth, with the diastolic pressure being gradually reduced to 85 to 90 mmHg over two to three months.
Methylprednisolone acetate, sold under the brand names Depo-Medrol among others, is a synthetic glucocorticoid corticosteroid and a corticosteroid ester—specifically the C21 acetate ester of methylprednisolone—which is used in clinical and veterinary medicine. It has been formulated as an aqueous suspension for intramuscular, intra-articular, soft tissue, and intralesional injection alone and in combination with lidocaine, a local anesthetic. Methylprednisolone acetate was previously suspended with polyethylene glycol but is no longer formulated with this excipient due to concerns about possible toxicity. Depo methylprednisolone acetate is a depot injection and is absorbed slowly with a duration of weeks to months with a single intramuscular injection. See also
List of corticosteroid esters § Methylprednisolone esters


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