J Korean Radiol Soc 1999 ; 40: 173-179

Imaging Findings ofNeonatal Adrenal Disorders 1

Hye-Kyung Yoon, M.D., Bokyung Kim Han, M.D., Min Hee Lee, M.D.

In newborn infants, normal adrenal glands are characterized by a relatively thin echogenic center surrounded by a thick, hypoechoic cortical rim as seen on ultrasound (US). Various disorders involving the neonatal adrenal gland include ad renal hemorrhage, hyperplasia, cyst, Wolman’s disease, and congenital neuro­ blastoma. Adrenal hemorrhage is the most common cause of an adrenal mass in the neonate, though differentiation between adrenal hemorrhage and neuroblastoma is in many cases difficult. We describe characteristic US, CT and MR imaging findings in neonates with various adrenal disorders.

Index words : Infants, newborn, genitourinary system Adrenal gland, abnormalities

Neonatal adrenal glands are clearJy demonstrated on uJtrasound (US) using high-freguency linear or phased Normal Neonatal Adrenal Glands array transducers. The normaJ neonataJ adrenaJ gland is clearly seen on postnatal abdominal sonograms, The appearance of neonatal adrenal glands varies; consisting of an echolucent cortex and a thinner they may be lambdoid, V- or Y-shaped, and are rela echogenic centraJ med ull a. AdrenaJ hemorrhage is the tively large (1). On US, corticomeduJJ ary differen most common adrenal mass in neonates. US is used as tiation is evident, with an outer echolucent cortex and the initiaJ modaJity for diagnosing adrenaJ hemor­ a central echogenic line representing the medulla (Fig. rhage, the appearance of which is varied and changes lA and B). The cortex is prominent in normal newborn over time. Other less frequent disorders occurring in infants because of the presence of a thick transient the neonatal adrenal glands include congenital adrenal fetal cortex, which involutes rapidly during the first hyperplasia (adrenogenitaJ syndrome), lipoid adrenaJ three weeks of life and completes the synthesis of ma­ hyperplasia, adrenaJ cyst, W oJm an’ s disease, and con­ ternally produced precursor steroids to make genital neuroblastoma. Computed tomography (CT) is estrogens d uring the third trimester of pregnancy. excellent for depicting calcification or fat density After the neonatal period, the hypoechoic peripheral associated with adrenallesions but beca use of the lack zone becomes smaller on US as the fetal cortex of retroperitoneal fat is less usefuJ for the demon­ involutes. When ipsilateral renal agenesis or ectopia is stration of normaJ adrenal glands. CT and/or magnetic present, the shape of adrenal gland is discoid and resonance (MR) imaging may be helpful for evaJuating elongated (Fig. lC). the extent and tissue characterization of an adrenal mass. Adrenal Hemorrhage

Idiopathic neonataJ adrenal hemorrhage is usuaJJy asymptomatic and freguentJy discovered as an inci­ IDcparlmcnt of Radiology, Samsung Medi ca l Cc ntcr, Sungk y unk wa n Uni versity dentaJ finding on US (1). A large baby, difficult deliv­ Co ll egc 0 1' Medici nc ery, and perinatal hypoxia have been reported as pre­ Rcceived June 5, 1998 ; Accepled Se plember 8, 1998 Addrcss reprinl requcsls to: Hye-Kyu ng Yoon, M.D. , Depar tment ofRad io logy, disposing factors in neonataJ adrenaJ hemorrhage. On Sa msu ng Medica l Center, ~ 50 Irwon-d o ng, Kangnam-gll , SCO ll l. 135-7 10, US, hemorrhage can be echogenic, echolucent or Korca TeI. 82-2-3410-25 18 Fax.82- 2-3410. 2559

- 173 - Hye-Kyung Yoon, et al : Imaging Findings of Neonatal Adrenal Disorders mixed in appearance, depending on its age (Fig. 2, 3) pletely obliterated. A diagnosis of adrenal hemorrhage The adrenal gland may be discernible in part or com is based on sequential US examinations and involves

A B Fig. 1. Normal adrenal glands in new born infants A. Abdominal US in a newborn infant shows lambda­ shaped right adrenal gland (arrows) with thick echolucent cortex and echogenic central line of the medulla. RK = right kidney. B. US with prone position in another newborn infant demonstrates large and thick limbs of the adrenal gland (arrows). The corticomedullary differentiation is clearly seen. C. Longitudinal US through the right renal fossa shows the elongated adrenal gland (arrow). In this case, right kidney (not shown) was seen in lower abdominal cav 때 and was fused with the lower pole of left kidney (crossed fused ectopyl

C

A B Fig. 2. Neonatal adrenal hemorrhage A. Longitudinal US shows left adrenal hemorrhage (calipers) with mixed solid and cystic appearance. Note relative preser­ vation ofthe normal triangular shape. LK = left kidney. B. Three months later, left adrenal hemorrhage seen on the figure A is completely resolved. - 174 - J Korean Radiol Soc 1999; 40: 173-179 demonstration of liquefaction and regression. Calcifi Adrenal hemorrhage may involve only a part of the cation at its periphery is common (Fig. 3C). Due to the adrenal gland even when normal contour is preserved paramagnetic effect of methemoglobin, MR imaging (2). When it primarily involves the adrenal medulla, (Fig. 3B) clearly shows adrenal hemorrhage of high sig­ normal configuration of the gland and the cortex is nal intensity on precontrast Tl-weighted images. preserved (Fig. 4)

A B Fig. 3. Neonatal adrenal hemorrhage with calcification. A. Longitudinal sonogram shows adrenal hemorrhage (H) above right kidney (RK), with a predominantly solid appear­ ance B. Tl -weighted axial MR image shows a large hyperintense hematoma (arrowheads) in the right adrenal gland with central isosignal intensity suggesting resolving hemorrhage. c. Two weeks later, right adrenal hemorrhage has decreased in size with eggshell-like calcification in the periphery of the resolving hematoma (arrowheads). RK = right kidney

C

A B Fig. 4. Adrenal med 1I11 ary hemorrhage in a newborn Transverse (A) and longitudinal (B) US scans of the adrenal region show normal hypoechoic co rtices of both adrenal glands

(arrowheads)‘ However, echogenic adrenal med lI11ae (m) are markedly thickened.

175 Hye-Kyung Yoon , et al : Imaging Findings of Neonatal Adrenal Disorders

tumor (Fig. 5C and D) Congenital Adrenal Hyperplasia Congenital Li poid Adrenal Hyperplasia Enzymatic defects at any site of adrenal steroid biosynthesis result in cortisol deficiency and second­ Conversion of cholesterol to pregnenolone is an es ary overproduction of pituitary corticotropin, which sential step in the synthesis of all adrenocortical in turn overproduces androgens. Congenital adrenal hormones. Infants with 20, 22-desmolase deficiency hyperplasia or adrenogenital syndrome causes am­ cannot synthesize any glucocorticoid, mineralo­ biguous genitalia, pseudohermaphroditism in females corticoid, or sex steroid. The adrenal glands are and an enlarged penis and precocious puberty in enlarged and filled with cholesterol and other lipids, males. Deficiency of 21-hydroxylase is the most com­ which explains echogenecity on US and hypodensity mon form of congenital adrenal hyperplasia, and dif­ on CT scan (5) (Fig. 6) fuse or nodular enlargement of the adrenal cortex occurs in many but not all babies with this condition Adrenal Cyst (2 , 3). US may show diffuse adrenal enlargement with a wrinkled, wavy, cerebriform appearance and loss of Adrenal cysts may be parasitic, epitheliaL endo normal corticomedullary differentiation (Fig. 5). Oc thelial or pseudocysts; true epithelium-lined adrenal casionally, adrenal enlargement may mimic adrenal cysts are rare in the neonate. Cystic lesions of the mass but bilateral involvement with relative preser­ adrenal glands are usually pseudocysts (hemorrhagic vation of gland configuration can exclude adrenal cysts) secondary to resolving adrenal hemorrhage.

A B Fig. 5. Congenital adrenal hyperplasia in a newborn girl with virilization and dark pigmentation Right (A) and left (8) adrenal glands show diffuse enlargement with cer­ ebriform appearance (arrows). L = liver, S = spleen. C. Transverse US in another female infant with congenital adrenal hyper­ plasia reveals diffuse enlargement of bilateral adrenal glands (arrowheads). D. T2-weighted coronal MR image in the same patient to C shows diffuse enlargement of the adrenal glands (arrows) with preservation ofthe nor­ mal triangular configuration C D τω J Korean Radiol Soc 1999 ; 40: 173-179

Adrenal cystic masses h ave been d escribed in associ­ ation with complete or incomplete forms of Beckwith­ Wolman’ s Disease Wiedemann syndrome (6, 7) (Fig. 7) . Because an adrenal cyst cannot be clearly distinguished from the Wolman’ s disease is a fatal xanthomatosis of cystic neuroblastoma occurring in association with autosomal recessive inheritance and is characterized Beckwith-Wiedemann syndrome, close observation, as by failure to thrive, hepatosplenomegaly, vomiting, well as US or surgical con firmation , is needed. and steatorrhea. Uniform bilateral adrenal enlargement with calcification is pathognomonic (8). Calcification

Fig. 6. Congenitallipoid adrenal hyperplasia. A. Longitudinal US scan of the left f1 ank shows enlarged adrenal gland (arrows) above the left kidney (LK). The gland appears diffusely echogenic with loss of corticomed ullary differentiation. A 8. Unenhanced CT scan at the level of adrenal gland shows thickened both adrenal glands with low attenuation, indicating fatty infiltration

A B c Fig. 7. Adrenal cystic mass in a newborn girl with Beckwith-Wiedemann syndrome Longitudinal US sca n (A) shows a large, well-demarcated cystic mass with homogeneous internal echoes above the right kid ney (RK). T2-weighted (8) and postcontrast Tl -weighted (C) coronal images show a large suprarenal cystic mass (M) with homogeneous high signal intensity on T2-weighted image without enhancing so lid portion. Right kidney (RK) is displaced and rotated inferiorly and media ll y. Surgical removal with histologic examination confirmed hemorrhagic cyst ofthe right ad renal gland 177 - Hye-Kyung Yoon. et al : Imaging Findings of Neonatal Adrenal Disorders

A 8 C

Fig. 8. Wolman disease in a 45-day­ old boy. A. Plain radiograph shows triangular calcifications in both suprarenal regions (arrowheads) B. Transverse US scan shows calcifi cations along both adrenallimbs with acoustic shadowing (arrows) C. Unenhanced CT scan clearly shows extensive adrenal calcifications with lamellated appearance (arrows). Coronal Tl (0) and T2-weighted (E) MR images show bilateraL symmetri­ cal enlargement of the adrenal glands (arrows) with alternating low and isosignal intensities suggesting lamel­ lated calcifications. Note preservation of normal adrenal gland configur­ D E atJOn.

A B Fig . 9. Congenital neuroblastoma A. Longitudinal US scan in a newborn girl shows a well-demarcated, homogeneously echogenic mass (M) above the right kid­ ney (RK). Surgery confirmed neuroblastoma originating from the right adrenal gland. B. Extraadrenal neuroblastoma in a newborn baby. Transverse US scan shows a retrocaval mass (arrows) which is partly cys­ tic and solid. At surgery, it was proved to be a retroperitoneal neuroblastoma with hemorrhage in the vicinity ofright adrenal gland. V = inferior vena cava, RK = right kidney 178 J Korean Radiol Soc 1999; 40 : 173-179 throughout the glands is clearly demonstrated on plain References radiograph, US, and CT (Fig. 8). On MR images, both adrenal glands are diffusely thickened with linear iso 1. Westra SJ, Zan inovic AC, Hal! TR, Kangaloo H, Boechat MI or hypointensity, suggesting calcification (Fig. 8 D and Imaging ofthe adrenal gland in children. RadioGraphics 1994 ; 14 E). 1323- 1340 2. Coh en EK , Daneman A, Stringer DA, Soto G, Thorner P. Focal

adrenal hemorrhage : a new ul trasonograp hic appeara nce ‘ Radi Congenital Neuroblastoma %gy 1986; 16 1 ‘ 631-633 3. Sivit CJ, Hung W, Tay lor GA, Catena LM, Browne-Jones C, Congenital neuroblastoma should be considered in Kushner DC. Sonography in neo natal co ngenital adrenal hyper­ the differential diagnosis of a neonatal suprarenal pl asia. AJR 199 1 ; 156: 14 1- 143 mass. Cystic neuroblastoma is more common during 4. Avni EF, Rypens F, Smet MH, Gal etty E. Sonographi c demon­ stration of congenital adrenal hyperplasia in the neonate: the ce r the neonatal period than at any other age, though it ebriform pattern . Pediatr Radio/ 1993; 23 : 88-90 may be difficult or even impossible to differentiate 5. Ogata T, Jshikawa K, Kohda E, Matsuo N. Computed tomography neonatal neuroblastoma from adrenal hemorrhage, es­ in the earl y detection of congenital lipoid adrenal hyperplasia pecially when the tumor is cystic or hemorrhagic (9) Pediatr Radio1 1988; 18: 360-361 Ne uroblastoma tends to remain static over the first two 6. McClauley RGK, Beckwith JB, Elia s ER, Faerber EN, Prewitt LH, Jr, Berdon WE. Benign hemorrhagic macrocysts in Beckwith­ weeks of life as compared to adrenal hemorrhage. US Wi edemann Syndrome. A JR 1991 ; 157: 549-552 demonstrates a cystic or solid-appearing suprarenal 7. Akata D, Haliloglu M, Ozmen MN, Ak han O. Bi lateral cystic mass originating from the adrenal gland or paraver­ adrena l masses in the neonate associated with the incomplete for m tebral sympathetic chain (Fig . 9). ofBeckwith-Wiedemann syndrome. Pediatr Radiol 1997; 27: 1-2 8. Duttton RV . Wolman’ 5 disease: ultraso nographic and computed tomographic di agnosis. Pediatr Radiol 1985; 15 : 144-146 9. Hendry GMA. Cystic neuroblastoma ofthe ad renal gland : a poten tial so urce of error in ultraso ni c diagnos is. Pediatr Radiol 1982; 12 204-206

대한방시선의학회 XI1999 ; 40: 1 73-1 79

신생아부신질환의 영상소견

l 성균관대학교의과대학삼성의료원방사선과

윤혜경·검보경·이민희

신생아의 정상부신은초음파에서 두터운저 에코의 피질 과앓은고 에 코의 수질로보이는 것 이 특정 이다.신생아 의 부신을침범하는질환은다양하며 부신출혈 ， 부신과증식 ，냥종 ， 선천성 신 경 아세 포종등이 있다.이 중부신출혈 이 가장 흔한데，신경아세 포종과의 감별이 어려 운경우도있다.저자들은 신생아의 여러 부신질환에서 특정적인초음 파，전산화단순촬영 ，자기공명영상 소견을보고하고자하였 다.

- 179 - 삼성제일병원 조음파 연수교육 안내

4th REFRESHER COURSE ON OBSTETRIC SONOGRAPHY -FETAL THORAX AND ABDOMEN-

8: 30- 9 : 00 야똑

9 : 00 - 9: 30 Normal sonographic anatomy 01 the letal thorax and abdomen 이영호(삼성제일병원)

9 : 30- 9:50 Fetallung mass 솜미진(삼성제일병원) 9 : 50 -1 0 : 30 Delects 01 the diaphragm and abdominal wall in the letus 조경식(울 산 의 대)

10 : 50-11 :10 Fetuses with pleural effusion and ascites 앙재혁(삼성제일병원)

11 : 10 -11 : 40 Systematic approach to letal i ntestinal obstruction 이영호(삼성제일병원) 11 : 40-12 : 10 Differential diagnosisolletal abdominal masses 김승협(서 울 의 대)

13 : 30 - 14 : 10 Postnatal treatment and outcome 01 the letuses with thoracic 박귀원(서 울 의 대) and abdominal abnormal ities

14 : 10 -14 : 40 Obstructive diseases 01 the letal urinary tract 조정연(삼성제일병원)

14: 40 -15 ‘ 00 Signilicance 01 mild dilatation olletal renal pelvis 양순하(삼성서울병원)

15: 20 -15 ’ 50 Pathology 01 cystic disease 01 kidneys 홍성 란(삼성제일병원)

15 : 50 - 16 : 1 0 Sonog raphy 01 the cystic diseases 01 the letal ki dneys 김보련(삼성서울병원)

16 : 10 -16 : 40 Postnatal treatment and outcome 01 the letuses with urinary 한상원(연 세 의 대) tract abnormalities

16 : 40 -17 : 00 Fetal interventional procedures lor thoracic and 김문영(삼성제일병원) abdominal abnormalities

*수강신청안내*

일 시 : 1999 년 4 월 18 일( 일) 장 소:삼성서울병원 대강당(일원동소재) 대 상:산부인과， 진단방사선과 전문의 및 전공의 연수교육책임자 : 이영호(성균관의대 삼성제일병원 진단방사선과 2262-7145) 연수핑점 :6 점

연수교육등록 : 사전등록( 마감일 : 1999 년 4월 16일) 등 록 비 : 전문의 70.000 원， 전공의 40.000원 등록방법 : 등록비 송긍후 전화 .FAX. 우편으로 사전등록 기획과/ 윤희숙 CTel 2262-7717. Fax 2262-7719) 등록비송금 : 한빛은행 050-095977-02-503 윤희숙 (등록시 성명， 소속， 전화번호， 으|사면허번호 기재)

180 -