Abstract
Background We report an unusual case of an acute subdural hygroma mimicking hemi-pachymeningitis in a young male with a history of alcohol dependence and dermatological lupus.
Method Case Report
Result A 42-year-old-man with a history of alcohol dependence, chronic thrombocytopenia and dermatological lupus presented with two generalised tonic-clonic seizures in the setting of alcohol withdrawal. Post seizure hyperpyrexia led to empirical initiation of infective encephalitis cover with aciclovir and ceftriaxone. He also had clinical Wernicke’s encephalopathy, treated with thiamine. Initial CT of the brain demonstrated a right sided parietal scalp haematoma but no intracranial pathology, and in particular no subdural collection. MRI brain three days into admission showed what appeared to be uniform hemi-pachymeningeal contrast enhancement on post contrast fluid attenuated inversion recovery (FLAIR) imaging suggesting unilateral pachymeningitis. However, further review of the images showed presence of CSF signal over the left cerebral convexity which was exhibiting progressive contrast enhancement. The repeat CT brain confirmed the interim development of a hypodense subdural collection on the left in keeping with an acute subdural hygroma. This was managed conservatively. The patient remained clinically well and was discharged home.
Conclusion Acute traumatic subdural hygroma can occur without a subdural hematoma. The striking enhancement of the subdural CSF space in these cases on contrast enhanced MRI, as noted in our case, may mimic ‘hemi-pachymeningitis’ radiologically. This hemi-meningeal enhancement pattern is rarely seen and may not be of an inflammatory nature as seen in this case with subdural hygroma.
