Comparative Assessment of Transcranial Doppler and MRI Perfusion Imaging in a Japanese Child With Probable Brain Death

The determination of brain death differs internationally, although in Japan, it is legally recognized only when organ donation is intended. Otherwise, the condition is termed probable brain death. Ancillary tests, including transcranial Doppler (TCD) ultrasonography, are not routinely incorporated into the clinical framework for pediatric brain death evaluation. In this report, we describe the case of a Japanese child with probable brain death, in whom both TCD and MRI revealed an absence of cerebral perfusion, providing valuable comparative data. A four-year-old girl with influenza A who developed recurrent seizures was diagnosed with influenza encephalopathy. Despite intensive treatment, no neurological improvement was observed, and she finally met the Japanese criteria for probable brain death. TCD, performed via bilateral temporal windows using a Phillips EPIQ Elite ultrasound system (Philips Healthcare, Sydney, New South Wales, Australia) equipped with an S5-1 probe, revealed no intracranial blood flow, even at a minimum color Doppler velocity of 1.4 cm/s. Consistently, preliminary MRI, including magnetic resonance angiography (MRA) and arterial spin labeling (ASL), had revealed an absence of cerebral perfusion. This is the first Japanese pediatric report directly comparing TCD and MRI with ASL in a case of probable brain death. The concordant absence of cerebral perfusion provides evidence for the diagnostic reliability of TCD as a potential adjunctive tool in Japan, in which, although not legally required, ancillary testing may aid clinical assessment and family discussions.