Morphological diagnostics of traumatic brain injury

INTRODUCTION. The classification of mechanical brain injury (MBI) includes a division by type of injury (closed/open, penetrating/non-penetrating), by the nature of brain damage (concussion, contusion, diffuse axonal injury, compression), by severity (mild, moderate, severe), and by biomechanics (impact-counterimpact, acceleration-deceleration, combined), as well as by the periods of the course (acute, intermediate, remote). The classification emphasizes the sequence of development and interaction of pathological processes that unfold after brain injury.

MATERIALS AND METHODS. Verification of the pathological process allows for the selection of a treatment protocol in the shortest possible time, which undoubtedly increases the survival rate of patients. Diagnostic methods that accurately perform this function are of particular importance. These methods include CT (computed tomography), MRI (magnetic resonance imaging), and fine-needle biopsy of the pathological lesion through a single drill hole in the cranial vault, which allows for a reliable morphological conclusion. Cytological and histological methods were used in the study of 47 biopsies obtained during diagnostic operations on the brain. 19 preparations obtained from stereotactic biopsies and 28 preparations obtained from open brain surgeries were studied. The preparations were examined using histological and cytological methods. Standard preparation techniques were used for histological examination.

RESULTS. In patients with severe brain concussions (commotions), circulatory disorders are the main feature of the pathoanatomical picture. Five stereotactic biopsies (performed on the first day) revealed vascular spasms, moderate venous congestion, and pericellular and perivascular edema of the brain and meninges. Twelve hours after the injury (seven cases), diapedetic hemorrhages resembling petechiae were observed in the brain biopsy samples. Petechial hemorrhages resulting from the rupture of small vessels. The petechiae were located in the white matter. In two cases, they were located in the subependymal layer of the walls of the Sylvian aqueduct and the bottom of the fourth ventricle. On the second day (3 cases), as a result of the clinical manifestations of increasing brain edema (CT and MRI did not reveal significant changes), changes in the nerve cells of a dystrophic nature were observed. In one case, there was vacuolization and fragmentation, accompanied by tyroglyosis and a retrograde pattern. When drawing parallels between the clinical course of concussion and diagnostic methods, the most accurate results were obtained from the performed biopsy study. In 11 cases, the patients’ condition was considered to be of moderate severity (CT and MRI were performed), however, after the biopsy study, in 7 cases, the severity was changed to severe, which accounted for 64.7 %. Contusion foci on macroscopic examination were foci of hemorrhagic softening or spots of hemorrhagic imbibition. In fresh cases (up to 5 cases per day), they were dark red in color. In two cases, there was a rupture of the meninges with the bulging of brain detritus. Two patients died 2 weeks after the injury. On section, the contusion foci had a cup-shaped appearance. There was a zone of necrosis (direct destruction) and a border zone (zone of secondary disintegration). The compression syndrome occurred on the third day. There was a complex morphological pattern.

CONCLUSION. Morphological diagnosis of brain injury is an important step in verifying the severity of the process. Clinical symptoms of brain damage do not always correspond to the severity of the injury and the results of CT and MRI scans, which can lead to underestimation of the patient’s condition and unpredictable complications. More than half of the errors are related to the diagnosis of the severity of concussion, which is often based solely on clinical symptoms. In complex clinical cases, we recommend performing a stereotactic biopsy as the most accurate diagnostic method.

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