Brainstem tegmental lesions in neonates with hypoxic-ischemic encephalopathy: Magnetic resonance diagnosis and clinical outcome

Figure 1 Schematic diagram of the brainstem vasculature. A: Rostral pons; B: Caudal pons; C: Rostral medulla oblongata; D: Caudal medulla oblongata. Basilar artery, the terminal paramedian, short circumferential and long circumferential arteries are depicted. Blue shaded areas represent the tegmental watershed areas that are most frequently affected in neonates and infants with dorsal brainstem syndrome and a history of hypoxic-ischemic encephalopathy.

Figure 2 Brainstem tegmental lesions and oral motor dysfunction. An infant with perinatal asphyxia due to knotting of umbilical cord around the neck is shown. Apgar score at five minutes after birth. Eighteen days after birth (panels B, F, J and N), MR images show faint T2 hyperintense (white arrows in F, J, and N) bilateral and symmetric tegmental lesions of the caudal pons and medulla oblongata. Forty days after birth (panels C, D, G, H, K, L, O and P), MR images confirm T2 hyperintense (white arrows in G, K, and O) and T1 hypointense (white arrows in H, L, and P) bilateral and symmetric tegmental lesions of the caudal pons and medulla oblongata. No signal alterations are detected at the level of the cranial pons (B-D) and at supratentorial level (Q). At 1 mo, an upper GI tract X-ray showed iodinated contrast (Iopamidol, IOPAMIRO 300) inhalation (black arrow in panel R points to the right bronchus). Gastrostomy was performed. At the age of 2 years, psychomotor delay and dysphagia are present. Sagittal views of the brainstem (panels A, E, I and M) are used for reference of axial images. MR: Magnetic resonance.

Figure 3 Brainstem tegmental lesions of the central tegmental tracts. A 1-year-old infant shows generalized hypotonia, macrocephaly and psycho-motor developmental delay, without a history of hypoxic-ischemic encephalopathy or adverse perinatal events. A genetic syndrome is suspected and is currently not known. MR images show isolated T2 hyperintense (white arrows in B, E, and H) and T1 hypointense (white arrows in C, F, and I) bilateral and symmetric tegmental lesions of the pons and caudal midbrain. Faint T2 hyperintense signal is observed at the rostral medulla oblongata. Columnar shape of alterations is demonstrated in coronal T2 weighted images (J). No signal alterations are detected at the supratentorial level (J). Sagittal views of the brainstem (A, D, and G) are used for reference of axial images. MR: Magnetic resonance.