The effect of surgical treatment on the pathomorphology of encapsulated subdural hematomas

Background. Estimating the age of subdural hematomas is a critical task in forensic neuropathology. Capsular hemosiderosis is widely used as a morphological time marker; however, the potential confounding effect of prior neurosurgical intervention on this parameter has not been systematically investigated, which may compromise expert accuracy.
Objective. To assess the effect of surgical treatment on the quantitative pathomorphology of subdural hematoma capsules and to develop a regression model for hematoma age determination.
Materials and Methods. A retrospective, blinded morphometric study was performed on capsules of 65 fatal traumatic supratentorial subdural hematomas with known intervals from injury to death ranging from 3 to 90 days. In 43 cases, patients had undergone neurosurgical intervention (decompressive craniectomy); 22 cases were unoperated. Parameters assessed included maximum capsule thickness, relative volume of hemosiderosis, and cellular infiltration intensity.
Results. Neurosurgical treatment significantly reduced the rate of increase in intracapsular hemosiderosis relative volume, with the effect proportional to the duration of the postoperative period. No significant influence of surgery on capsule thickness or cellular infiltration was detected. A regression equation for hematoma age estimation, incorporating maximum capsule thickness and hemosiderosis volume, was developed and implemented as Calculator SDH Age 3.0.
Conclusion. Prior surgical treatment must be considered when estimating subdural hematoma age based on capsular hemosiderosis. The derived regression model and Calculator SDH Age 3.0 are recommended for forensic practice in dating unoperated encapsulated subdural hematomas.

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