Diffusion-Weighted Imaging of Traumatic Subdural Hematoma in the Subacute Stage-Five Case Reports-

Abstract

Five cases of traumatic subdural hematomas in the subacute stage (from 7 to 20 days after head injury) were treated in one male and four females, aged from 63 to 82 years, with evacuation via craniotomy in three and aspiration via burr hole surgery in two. All hematomas were evaluated by T 1 -, T 2 -, and diffusion-weighted magnetic resonance imaging, and measurement of the apparent diffusion coefficient (ADC). Diffusion-weighted imaging showed the hematoma as a crescent high intensity area with a low intensity rim close to the brain surface (two-layered structure) in four cases and as high intensity with low intensity components in one case. The high intensity areas under the dura mater on diffusion-weighted imaging appeared as homogeneous high intensity on T 1 -and T 2 -weighted imaging in four cases, and inhomogeneous high intensity on T 1 -and isointensity on T 2 -weighted imaging in one case. The mean ADC value of the high intensity areas was 0.58 ± 0.23 (mean ± standard deviation) × 10 -3 mm 2 /sec. The operative findings revealed the high intensity areas as solid clots. The low intensity areas on diffusion-weighted imaging appeared as homogeneous high intensity in four cases and inhomogeneous isointensity with high intensity components in one case on T 1 -and T 2 -weighted imaging. The mean ADC value of the low intensity areas was 2.03 ± 0.27 × 10 -3 mm 2 /sec. The operative findings revealed the low intensity areas as mixtures of resolved clot and cerebrospinal fluid. Diffusion-weighted imaging showed the characteristic two-layered structure in traumatic subdural hematomas in the subacute stage, and analysis of the ADC values was useful for differentiating solid from liquid hematoma and for selection of the surgical procedure.

Acute Subdural Hematoma Requiring Surgery in the Subacute or Chronic Stage

“…5,12) Therefore, the majority of reported clinical studies of SASDH have been conducted in Japan. 1,3,6,9,10,[13][14][15] SASDH has been reported to occur in approximately 10% of ASDH cases treated conservatively. 1,14) In the Subdural Hematoma Removal in the Subacute or Chronic Stage present study, SASDH was found in 7 (18.4%) of 38 patients, indicating that it is not uncommon.…”

“…1,3,6,9,14) These characteristics have included a comparatively thick high-density hematoma in the acute stage, expanding along the skull vault and including low-density components, an enlarged hematoma in the subacute stage showing a change to iso-or low density, a low prevalence of complicating traumatic lesions including brain swelling, and frequent occurrence of brain atrophy. On the other hand, the characteristics of SASDH evident on MR images have included gyrus patterns (a feature indirectly suggesting absence of an inner membrane) 3) on the brain surface side of a hematoma, and a two-layered hematoma structure 6) consisting of a high-intensity component (solid or jelly-like clot) and a low-intensity component (liquid hematoma) on diffusion-weighted MR images. The latter feature in particular has been reported to be useful for diagnosis and surgical decision-making in patients with SASDH.…”

“…14) However, in the subacute stage, clinical deterioration occasionally occurs associated with comparatively rapid enlargement of the hematoma, necessitating surgery, and this has recently been referred to as subacute subdural hematoma (SASDH). 1,3,6,9,10,[13][14][15] Our aim in the present study was to clarify the clinical characteristics and pathophysiology of patients with ASDH who ultimately required surgery in the subacute or chronic stage, and devise an appropriate form of management for them.…”

Subdural Hyperintense Band on Diffusion-Weighted Imaging of Chronic Subdural Hematoma Indicates Bleeding From the Outer Membrane

“…12,13) Diffusionweighted MR imaging has proved useful in a study of the natural history of ischemic stroke, 15) and is now a promising technique for early detection of cerebral infarction in routine clinical practice. 2,14,19,22) We recently confirmed that diffusion-weighted imaging showed solid clots as high intensity areas in patients with traumatic subacute subdural hematoma 10) and organized subdural hematoma, 11) and measurement of the apparent diffusion coefficient (ADC) values was useful for differentiating solid from liquid components. 11) However, the diffusionweighted imaging appearance of chronic subdural hematomas has been rarely reported, 9) and the potential of diffusion-weighted imaging for the evaluation of chronic subdural hematoma has not yet been established.…”

Diffusion-Weighted Magnetic Resonance Imaging of Organized Subdural Hematoma-Case Report-

“…5) We recently reported that diffusion-weighted MR imaging can differentiate solid from liquid hematoma in the subacute stage. 9) Here, we discuss the usefulness of diffusion-weighted MR imaging and apparent diffusion coefficient (ADC) values of the organized subdural hematoma.…”