A 6-month-old infant is brought dead to the emergency department. Autopsy reveals bilateral retinal haemorrhages, subdural haematoma in the interhemispheric fissure, and diffuse axonal injury, but NO external head injuries. The MOST likely mechanism responsible for the intracranial findings is:

• A Birth-related trauma from forceps delivery
• B Sudden infant death syndrome (SIDS) with secondary vascular rupture
• C Glutaric aciduria type I causing spontaneous subdural haemorrhage
• D Rotational acceleration-deceleration forces from violent shaking (abusive head trauma) ✓

Explanation

The triad of subdural haematoma, diffuse axonal injury, and bilateral retinal haemorrhages in an infant without external head injury is the hallmark of abusive head trauma (formerly shaken baby syndrome). Violent rotational acceleration-deceleration forces tear bridging veins and cause diffuse axonal injury, while retinal haemorrhages result from vitreoretinal traction during shaking. SIDS is a diagnosis of exclusion and does not explain these findings. Glutaric aciduria can cause subdural but typically not the full triad with retinal haemorrhages.

Reference: The Essentials of Forensic Medicine and Toxicology (Narayan Reddy), 34th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.