Organized Chronic Subdural Hematoma: A Condition Presenting Mixed-Density Hematoma without Gradation Density on Brain CT

Abstract

Organized chronic subdural hematoma is a neurological condition characterized by organized clot formation inside the hematoma. Unlike nonorganized chronic subdural hematoma with persistent bleeding inside, organized subdural hematoma is often a nonurgent condition that does not require emergency drainage, unless progressive cerebral compression with neurological disturbances is present. However, as the CT values in organized clot formation and active bleeding fall in similar ranges, distinguishing these 2 conditions with different emergency levels based on brain CT alone is sometimes difficult. Here, we describe the case of a 78-year-old man with persistent nocturia who was referred to our hospital. He had a history of head trauma on the left side about 1 year ago, followed by neurosurgery at another hospital. Brain CT revealed a multiseptated subdural space and a mixed-density hematoma without gradation density on the contralateral side of the past head trauma region. Based on the lack of progressive neurological disturbances and the absence of gradation density in CT values inside the hematomas, his condition was judged as nonurgent, and emergency drainage was spared. One year after his first visit to our hospital, the patient experienced a normal life without any neurological disturbances, except for nocturia. The absence of gradation density in CT values along the gravity direction inside the organized hematoma may be a clue to estimate nonurgency without persistent active bleeding inside.

Organized Chronic Subdural Hematoma Mimicking Acute Epidural Hematoma

“…The CT manifestations of organized chronic subdural hematoma are crescent, semilunar, or fusiform low or equal or high-density shadows under the inner plate of the skull, with annular septal or strip-shaped high-density shadows in some parts [ 7 ]. The midline structure shifts to the opposite side to varying degrees, the lateral ventricle is compressed and deformed, and most of the inner membrane presents high-density shadows.…”

Middle meningeal artery embolization before craniotomy for infected organizing chronic subdural hematoma: A case report and review of the literature

“…Preoperative diagnosis of an OSDH is difficult and cannot be made on plain CT unless it is accompanied by calcification. [ 1 ] Several characteristic findings have been reported through MRI. T1-weighted images show a heterogeneous web-like appearance within the hematoma cavity, and diffusion-weighted images show hard coagulation with high signal and liquid hematoma with low signal.…”