COMPLEX NUCHAL MASS

 

Organization Chart
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 


Occipital encephalocele –

Large defect seen on the ultrasound, CT scan and

Skull X-Ray

Cervical meningocele –

Large defect involving upper cervical spine and associated 

cystic meningocele

Amniotic membranes posterior to the fetal back

Nuchal cord posterior to the neck appears as a cystic

Lesion on gray-scale images, but color flow confirms that it is cord.

 

 

Placental cyst that mimics a nuchal mass

Twin sac of a blighted ovum

Cystic teratoma – note that the mass is complex and

Contains both solid and cystic components

 

 

NUCHAL CYSTIC HYGROMA

 

Cystic hygromas are congenital malformations of the lymphatic system, and are characterized by single or multiple fluid filled lesions that occur at sites of lymphatic-venous connection. Once considered diagnostic of Turner’s syndrome, they are now known to be associated with other karyotypic abnormalities and several malformation syndromes (1-6).

 

ULTRASOUND OF HYGROMA IN THE FIRST TRIMESTER

1.      Earliest sign is increased nuchal translucency. The degree of cystic changes is not as well developed, and septations are less likely.

2.      Chromosomal abnormalities are present in 50% (usually autosomal trisomy). See section on Nuchal translucency screening.

3.      If no chromosomal abnormality is present and no other sonographically detectable anomaly is present, the prognosis appears good. They are usually small, unilocular and unilateral, and often resolve with a normal postnatal appearance (7). It is thought to be due to a delay in the jugulo-lymphatic connection that results in transient fluid in the neck that resolves once the connection is established.

 

Cystic hygromas between 9-14 weeks

Chromosomal abnormalities (29%)

No chromosomal abnormalities (71%)

Trisomy 18 (38%)

Adverse outcome (30%)

Trisomy 21 (31%)

 

Turners syndrome (XO) (25%)

 

47,XXX (6%)

 

 

ULTRASOUND OF HYGROMA IN THE SECOND TRIMESTER

 

Lesions that persist into the second trimester or lesions that are discovered in the second trimester are associated with a poorer prognosis (1-5).

      1.   Midline cervical mass with midline septum (ligamentum

            nuchae).

  1. Normal cranium and spine.
  2. No intracranial connection to mass.
  3. No solid components.
  4. Movement of mass is related to fetal head movements (large hygromas may restrict movement).
  5. +/- pleural / pericardial effusion/ascites.
  6. +/- generalized hydrops.
  7. Strong association with aneuploidy especially Turners Syndrome
  8. May also be seen in Noonan's Syndrome
  9. Strong association between septations and aneuploidy.
  10. Strong association between the size of the hygroma and aneuploidy.
  11. Non-immune hydrops has a poor prognosis but is not invariably fatal. 
  12. 50-70 % are aneuploid (especially Turner’s syndrome).

 

 

3D Cystic hygroma

      

 

 

 

Cystic hygromata associated with a normal karyotype may have a wide range of inherited disorders and malformation syndromes (9).

    1. Achondrogenesis type II
    2. Achondroplasia
    3. Beckwith-Wiederman syndrome
    4. Brachmann-de Lange syndrome
    5. Cumming syndrome
    6. Distichiasis-lymphedema syndrome
    7. Fraser syndrome
    8. Fryns syndrome
    9. Hereditary lymphedema
    10. Multiple pterygium syndrome
    11. Noonan syndrome
    12. Oculo-dental digital syndrome
    13. Opitz-Frias syndrome
    14. Pena-Shokeir syndrome
    15. Polysplenia syndrome
    16. Proteus syndrome
    17. Roberts syndrome
    18. TAR syndrome
    19. Williams syndrome
    20. Zellwegers syndrome

 

The risk of a second malformation is estimated at 30% - persistent left superior vena cava, intestinal malrotation, duodenal atresia and imperforate anus (10).

Cystic hygromata have been associated with teratogen exposure including alcohol, aminopterin and trimethadione (5).

 

 

 

Video clip of Cystic Hygroma

 

 

 

 

Chromosomal anomalies in 900 karyotyped fetuses with cystic hygroma (8)

   Chromosomal    

       Anomaly

 

All fetuses

First Trimester

Second Trimester

Turner’s syndrome (XO)

 

 31.3%

12.1%

         42.7%

Trisomy 21

 

  15%

21.4%

         11.3%

Trisomy 18

 

 7.3%

13.7%

           3.5%

Trisomy 13

 

 2.5%

   3%

           2.3%

Other abnormal karyotypes

 

3.9%

4.8%

           3.4%

Normal

 

40%

45%

         36.8%

 

Comparison of “non-septated “ cystic spaces

and septated cystic hygroma

 

“Nonseptated” cystic space”

Cystic hygroma

More likely to persist

2%

56%

Aneuploidy

5.6%

72%

Hydrops

1.7%

40%

Associated anomalies

15%

52%

Pregnancy loss

6%

88%

 

 REFERENCES
  1. MacLeod AM, McHugo JM. Prenatal Diagnosis of Nuchal Cystic Hygroma. Br J Radiol 1991; 64:802-807
  2. Bronshtein M, Bar-Hava I, Blumenfeld I et.al. The difference between Septated and Nonseptated Nuchal Cystic Hygroma in the early Second Trimester Obstetrics and Gynecology 1993; 81:683-687
  3. Suchet IB, van der Westhuizen NG, Labatte MF. Fetal cystic hygromas: further insights into their natural history. Can Assoc Radiol J 1992; 43:420-424
  4. Cullen MT, Gabrielli S, Green JJ et.al. Diagnosis and significance of cystic hygroma in the first trimester. Prenat Diagn 1990; 10:643-651
  5. Edwards MJ, Graham JM. Posterior Nuchal Cystic Hygroma. Clinics in Perinatology 1990; 17:611-640
  6. Chitayat D, Kalousek DK, Bamforth JS. Lymphatic abnormalities in fetuses with posterior cervical cystic hygroma. Am J Med Gen 1989; 33:352-356
  7. Bernstein HS, Filly RA, Goldberg JD et.al. Prognosis of fetuses with cystic hygromata. Prenat Diagn 1991;11:349-355
  8. Machin G. Hydrops, cystic hygroma, hydrothorax, pericardial effusion and fetal ascites. In: Gilbert Barness E (ed): Potters pathology of the fetus and infant. Mosby, St Louis 1997;pg 163-181
  9. Gallagher PG, Mahoney MJ, Gosche JR. Cystic hygroma in the fetus and newborn. Sem Perinatol 1999;23(4):341-356
  10. Geifman-Holtzman O, Drury HE, Holmes LB. Increased detection of cystic hygroma: A “technology-induced” phenomenon. Teratology 1996;54:298-302