Indian Journal of Radiology and Imaging Indian Journal of Radiology and Imaging

CNS
Year
: 2003  |  Volume : 13  |  Issue : 2  |  Page : 207--208

Anterior sacral meningocele - as part of the currarino triad


S Swamy, P Edwin, Babu Philip, Binu Joy, Radhika Devi 
 Department of Radiology, St. John's Medical College Hospital, Bangalore, 560034, India

Correspondence Address:
S Swamy
Department of Radiology, St. John«SQ»s Medical College Hospital, Bangalore, 560034
India




How to cite this article:
Swamy S, Edwin P, Philip B, Joy B, Devi R. Anterior sacral meningocele - as part of the currarino triad.Indian J Radiol Imaging 2003;13:207-208


How to cite this URL:
Swamy S, Edwin P, Philip B, Joy B, Devi R. Anterior sacral meningocele - as part of the currarino triad. Indian J Radiol Imaging [serial online] 2003 [cited 2019 Oct 21 ];13:207-208
Available from: http://www.ijri.org/text.asp?2003/13/2/207/28662


Full Text

A relatively uncommon cause of cystic masses in pelvis is the anterior sacral meningocele. This is a rare congenital malformation representing ventral dysraphism in which a persistant neuroenteric connection is delineated by a ventral meningeal pouch herniating through dysraphic vertebral elements [1]. The Currarino triad consisting of partial sacral agenesis, anorectal stenosis and a presacral mass has been described, about 50% of which are familial with autosomal dominant inheritance.

We report a patient with the stigmata of the Currarino triad. However a familial occurance could not be documented in this case.

 Case Report



A nineteen year old female presented to our hospital with a four month history of lower abdominal pain and urinary retention. She had a long standing history of chronic constipation. The patient had an ultrasound scan two months back which showed pelvic cysts, bicornuate uterus and bilateral hydronephrosis. For this she had apparently undergone a partial ovarian cystectomy under spinal anesthesia at a local polyclinic. However there was no relief of symptoms. Physical examination revealed an ill-defined mass in the suprapubic and both iliac regions. Though rectal examination revealed a loaded colon, rectal sphincter tone was found to be normal.

A CT scan was performed at our institution. This showed a large cystic mass in the pelvis with thick enhancing walls, displacing the rectum anterolaterally and the bladder superiorly. Another smaller mass with fat density was noted postero-inferior to the cyst [Figure 1]. The sacrum showed partial agenesis of the 2,3,4 segments on the right side. A diagnosis of anterior sacral meningocele was made and an MRI performed to further delineate the relations of the thecal sac. The sagittal T2W image showed low termination of the cord at L1-2 level. There were nerve filaments traversing the meningocele sac. The smaller inferior mass showed low signal on T2 and high signal on T1W images [Figure 2] suggestive of fat density, consistent with dermoid cyst. CT imaging was again performed after instillation of intrathecal contrast by lumbar puncture and this showed contrast layering into the larger cyst [Figure 3].

The patient was operated via a posterior sacral laminectomy. The dermoid cyst located at sacral 3,4,5 was decompressed and the capsule was excised.The anterior sacral collection was aspirated.

 Discussion



Anterior sacral meningocoele consists of a diverticulum of the thecal sac that protrudes anteriorly into the presacral space through a defect in the sacrum. The Scimitar sacrum is the most common of sacral anomalies that is invariably present. Most anterior sacral meningocoeles are sporadic. They may be seen in conditions with dural ectasia such as neurofibromatosis and Marfan's syndrome[2].

The Currarino triad refers to a specific malformation complex characterized by three main features - congenital anorectal stenosis (or any type of low anorectal malformation), anterior sacral defect and a presacral mass which may be a meningocoele / a teratoma / an enteric cyst or a combination thereof. Currarino et al in their review, suggested that this triad may be familial with autosomal dominant inheritance and variable penetrance. In members of the same family one or two basic features may be lacking suggesting an incomplete form of the syndrome[3].

Clinically these lesions occur equally in both genders in childhood but a female preponderance is seen in adults. The lesion may remain asymptomatic or be manifested by nonspecific symptoms such as constipation, urinary or reproductive symptoms due to local pressure effect. Pressure on nerve roots may lead to sciatica, decreased detrusor and rectal tone, paresthesia in the lower sclerotomes. During pregnancy it may lead to dystocia during labour. Meningitis is a rare but important complication usually occurring secondary to iatrogenic manipulation of the sac or more infrequently, due to pressure erosion of the anterior sacral meningocoele into the rectum [4].

Investigation by ultrasound will reveal uni or multilocular cysts - a high index of suspicion should be maintained in order to avoid disastrous consequences of cyst manipulation. Plain films will reveal the defects in the sacrum. CT is useful to visualize both the sacral agenesis component as well as the cyst and associated tumor, if any.

Typically the presacral mass will displace the rectum anteriorly. Intrathecal instillation of contrast will demonstrate the communication between the anterior sacral meningocoele and the subarachnoid space and also demonstrate associated tumor as a filling defect. MRI is advantageous in that it is safe, rapid, and noninvasive and due to its multiplanar capability, is able to demonstrate the sacral defect, anterior meningocoele, associated tumor and anomalies of the cord such as tethering.

Conservative treatment may be considered only in small lesions in males with no associated tumors. Surgical management is recommended in all other cases as there is no possibility of spontaneous regression [5].

References

1Thomas P. Naidich, Susan I. Blaser, Bradley N. Delman, David G. Mclone et al. Congenital anomalies of the spine and spinal cord: Embryology and malformations, In Scott W. Atlas, Magnetic Resonance Imaging of the Brain and Spine, 3rd Ed. Lipincott Williams and Wilkins 2002 : 1593-1595
2Derek C. Armstrong. Pediatric Spine, In David D. Stark, William G.Bradley Jr. Magnetic Resonance Imaging, Vol III 3rd ed. Mosby 1999: 1926-1927.
3Guido Currarino, Dale Coln, Theodore Votteler. Triad of anorectal, sacral and presacral anomalies, Amr J Rad 1981;137:395-398.
4Harold Brem, Bonnie L.Beaver, Paul M. Colombani, James Zenreich et al. Neonatal diagnosis of a presacral mass in the presence of congenital anal stenosis and partial sacral agenesis, J Ped Surg 1989;24:1076-1078.
5K.Stuart Lee, David J Gower, Joe M Mcwhorter, David A Albertson.The role of MRI in the diagnosis and treatment of anterior sacral meningocoele,,Journal of Neurosurgery,1988;69:628-631.