Transcranial ultrasound in neurodegeneration with brain iron accumulation (NBIA)

NBIA/HSS is a neurodegenerative disorder associated with iron accumulation in specific brain regions. To date, the diagnosis is obtained by typical MRI changes followed by genetic mutation analysis. This procedure is laborious and limited to a few specially equipped medical centres. Since transcranial sonography (TCS) is widely used for the early diagnosis of PD in adults displaying parenchymal metal deposits, it is likely to be a reliable diagnostic tool for the early diagnosis of NBIA.In 7 patients with proven NBIA and 13 age-matched controls without record of neurological disease TCS was performed by an experienced ultrasound examiner. Data were analysed by two blinded investigators regarding hyperechogenicity and size of the substantia nigra (SN). SN size and hyperechogenicity was significantly increased in patients with NBIA compared to controls (students t-test: p < 0.001).TCS appears to be a non-invasive and inexpensive screening technique in patients with suspected NBIA. Performed by an experienced physician, it could enable an earlier diagnosis and pre-selection of patients for the MRI scan and genetic testing, which are still the diagnostic gold standard.

► In this study we investigated transcranial ultrasound as a screening method for early and differential diagnosis in NBIA. ► TCS fingdings between NBIA patients and healthy control volunteers were compared. ► substantia nigra echogenicity was markedly increased in NBIA patients. ► In our opinion TCS may serve as an early screening method for suspected NBIA patients prior to MRI and genetic testing.