ADRENAL HEMORRHAGE

Adrenal hemorrhage usually occurs perinatally but has been demonstrated in utero (1, 2).

ULTRASOUND

• Subdiaphragmatic cystic mass (unilateral hemorrhage has only been described antenatally).
• The sonographic appearance depends on the stage after the active hemorrhage that the fetus is scanned.
• Fresh hemorrhage is echogenic and then becomes hypoechoic.

	Acute echogenic adrenal hemorrhage into the adrenal cortex.
Postnatal ultrasound

• The hypoechoic collection initially decreases in size and becomes more echogenic prior to involuting (1-4). Internal echoes due to fragmentation of the hemolysed clot develops producing multiple interfaces. This leads to a heterogeneous appearance that has a mixed echogenicity.
• At 3 months of age it has usually almost completely resolved.
• Spontaneous regression is followed by a classic rim of calcification leaving a normal sized calcified gland.
• The neonatal appearance falls into three main categories (5,6):
• Central hematoma (hematoma distorts the medulla and attenuates the overlying cortex).
• Total necrosis of one or both glands (gland is enlarged but maintains its shape).
• Segmental lesions (normal adrenal tissue is adjacent to the hemorrhage).
• The right adrenal is more commonly involved (75%) presumably as the vein is shorter and drains directly into the IVC whereas the left adrenal vein empties into the ipsilateral renal vein.

	Adrenal Hemorrhage at 30 wks GA – IUGR + fetal distress

DIFFERENTIAL DIAGNOSIS

• Renal pathology (hydronephrosis, nephroblastoma, cortical cyst) (1,2).
• Adrenal cyst.
• Neuroblastoma - involution is demonstrated between successive scans.

REFERENCES

1. Gotoh T, Adachi Y, Nounaka O et.al. Adrenal hemorrhage in the newborn with evidence of bleeding in utero. J Urol 1989;141:1145.
2. Lee W, Comstock CH, Jurcak-Zaleski S. Prenatal diagnosis of adrenal hemorrhage by ultrasonography. J Ultrasound Med 1992;11:369-371.
3. Pery M, Kaftori JK, Bar-Maor JA. Sonography for diagnosis and follow-up of neonatal adrenal hemorrhage. J Clin Ultrasound 1981;9:397.
4. Kenney PJ, Stanley RJ. Calcified adrenal masses. Urol Radiol 1987;9:9.
5. Cohen EK, Daneman A, Stringer DA et.al. Focal adrenal hemorrhage: A new ultrasound appearance. Radiology 1986;161:631.
6. DeSA DJ, Nicholls S. Hemorrhagic necrosis of the adrenal gland in perinatal infants. A clinico-pathological study. J Pathol 1971;106:133.