Subdural Hygromas in Abusive Head Trauma: Pathogenesis, Diagnosis, and Forensic Implications

Abstract

SUMMARY:Are subdural hygromas the result of abusive head trauma? CT and MR imaging represent important tools for the diagnosis of abusive head trauma in living infants. In addition, in-depth understanding of the pathogenesis of subdural hygromas is increasingly required by neuroradiologists, pediatricians, and forensic physicians. Therefore, the current knowledge on subdural hygromas is summarized and forensic conclusions are drawn. The most important diagnostic pitfalls, benign enlargement of the subarachnoid space, and chronic subdural hematoma, are discussed in detail. Illustrative cases from forensic practice are presented. Literature analysis indicates that subdural hygromas can occur immediately or be delayed. If other infrequent reasons can be excluded, the presence of subdural hygromas strongly suggests a posttraumatic state and should prompt the physician to search for other signs of abuse. To differentiate subdural hygromas from other pathologies, additional MR imaging of the infant's head is indispensable after initial CT scan. ABBREVIATIONS:AHT ϭ abusive head trauma; BESS ϭ benign enlargement of subarachnoid space; BV ϭ bridging vein; cSDH ϭ chronic subdural hematoma;

Macrocephaly in infancy: benign enlargement of the subarachnoid spaces and subdural collections

“…However, in the absence of a reliable rule for excluding the possibility of abuse, authors who express an opinion recommend investigation. 4,7,14,15 Whether-or how frequently-small, incidental collections evolve into large, symptomatic collections is another question of forensic concern. Incidental subdural collections resolved without treatment in all cases that had follow-up imaging in this series, but the small number of such cases does not support general conclusions.…”

Reply:

“…Hence, we still believe that the SDHy in this case "can be regarded as a result of acute injury." 1 We definitely agree with Drs Adamsbaum and Rey-Salmon that recognizing early clinical signs and symptoms of AHT is crucially important. In this context, we would also like to stress the vital importance of close and efficient cooperation among all medical disciplines involved in AHT cases (ie, pediatrics, ophthalmology, forensic medicine, and radiology in particular).…”

“…1 We are very grateful for their interest in our work. Because during neuroimaging we frequently observe the concomitant occurrence of hyper-and hypodense subdural collections (mixed-density pattern), in both the same location and at least 2 different locations, we were interested in the possible pathophysiologic mechanisms that underlie the formation of the hypodense component (ie, subdural hygromas [SDHys]).…”

“…The currently available literature reveals the presence of the 2 major hypotheses that we outlined in our review article (delayed and rapid formation of SDHys). 1 Of course, we are aware that the pathophysiology of SDHy formation is still an ongoing research process, and it seems very likely that multiple mechanisms exist and coexist.…”

Head Circumference: A Key Sign in Dating Abusive Head Trauma

“…T he article by Wittschieber et al 1 offers very interesting insights into subdural hygromas (SDHys) in the particular context of abusive head trauma (AHT).…”