Answer for BIR CoW 29 Oct 2023
Presacral Epidermoid Cyst
Findings
Anterior sacral defect at S3 level, with a small presacral meningocele at this level, which appears to communicate with the spinal canal with traversing nerve roots. Another large cystic lesion with no abnormal contrast enhancement, abutting anteriorly to the above lesion showing restricted diffusion, suggestive of Epidermoid cyst.
Discussion
Developmental cystic lesions arising in the presacral location include a multitude of tumors, including dermoid cysts, epidermoid cysts, chordomas, adrenal rest tumors, anterior sacral meningoceles, cystic hamartomas, tailgut or rectal duplication cysts Bony defects may be seen in cases of dermoid, tailgut, and neurenteric cysts. Spinal canal or meningeal communication may be demonstrated in anterior sacral meningoceles, while communication with the rectum may be demonstrated in rectal duplication cysts. Tailgut cysts usually show presence of wall calcifications and internal septations. High signals on T1 weighted MR imaging may be seen in tailgut cysts or dermoid cysts due to presence of mucinous material and fat, respectively Developmental cystic lesions arising in the presacral location include a multitude of tumors, including dermoid cysts, epidermoid cysts, chordomas, adrenal rest tumors, anterior sacral meningoceles, cystic hamartomas, tailgut or rectal duplication cysts Bony defects may be seen in cases of dermoid, tailgut, and neurenteric cysts. Spinal canal or meningeal communication may be demonstrated in anterior sacral meningoceles, while communication with the rectum may be demonstrated in rectal duplication cysts. Tailgut cysts usually show presence of wall calcifications and internal septations. High signals on T1 weighted MR imaging may be seen in tailgut cysts or dermoid cysts due to presence of mucinous material and fat, respectively Epidermoid cysts appear as T1 hypointense, T2 hyperintense masses which show diffusion restriction, wherever they are present within the body. T2 hypointense foci may be seen within the lesion because of presence of keratin There was differential restriction in its contents. Posteriorly, the contents were showing relatively more hyperintense signals on DWI, likely correlating with keratin deposition The closest differential of an epidermoid cyst on basis of diffusion restriction is a retrorectal pyogenic abscess. However, there is absence of constitutional symptoms in an epidermoid cyst. Also, there is a peripherally enhancing rim in an abscess. Correct diagnosis and proper treatment for a presacral lesion is very important as inadequate primary surgery can increase the risk of recurrence and can even cause complications such as fecal incontinence
Findings
Anterior sacral defect at S3 level, with a small presacral meningocele at this level, which appears to communicate with the spinal canal with traversing nerve roots. Another large cystic lesion with no abnormal contrast enhancement, abutting anteriorly to the above lesion showing restricted diffusion, suggestive of Epidermoid cyst.
Discussion
Developmental cystic lesions arising in the presacral location include a multitude of tumors, including dermoid cysts, epidermoid cysts, chordomas, adrenal rest tumors, anterior sacral meningoceles, cystic hamartomas, tailgut or rectal duplication cysts Bony defects may be seen in cases of dermoid, tailgut, and neurenteric cysts. Spinal canal or meningeal communication may be demonstrated in anterior sacral meningoceles, while communication with the rectum may be demonstrated in rectal duplication cysts. Tailgut cysts usually show presence of wall calcifications and internal septations. High signals on T1 weighted MR imaging may be seen in tailgut cysts or dermoid cysts due to presence of mucinous material and fat, respectively Developmental cystic lesions arising in the presacral location include a multitude of tumors, including dermoid cysts, epidermoid cysts, chordomas, adrenal rest tumors, anterior sacral meningoceles, cystic hamartomas, tailgut or rectal duplication cysts Bony defects may be seen in cases of dermoid, tailgut, and neurenteric cysts. Spinal canal or meningeal communication may be demonstrated in anterior sacral meningoceles, while communication with the rectum may be demonstrated in rectal duplication cysts. Tailgut cysts usually show presence of wall calcifications and internal septations. High signals on T1 weighted MR imaging may be seen in tailgut cysts or dermoid cysts due to presence of mucinous material and fat, respectively Epidermoid cysts appear as T1 hypointense, T2 hyperintense masses which show diffusion restriction, wherever they are present within the body. T2 hypointense foci may be seen within the lesion because of presence of keratin There was differential restriction in its contents. Posteriorly, the contents were showing relatively more hyperintense signals on DWI, likely correlating with keratin deposition The closest differential of an epidermoid cyst on basis of diffusion restriction is a retrorectal pyogenic abscess. However, there is absence of constitutional symptoms in an epidermoid cyst. Also, there is a peripherally enhancing rim in an abscess. Correct diagnosis and proper treatment for a presacral lesion is very important as inadequate primary surgery can increase the risk of recurrence and can even cause complications such as fecal incontinence
Note:
We do not discourage differential diagnosis. But all the differentials must satisfy the findings noted in the case.
If you feel you have answered rightly but cannot find your name in the above list, please call 09551942599.
Did you Know?
The order in which the names appear in this winner's list is based on the time of submission. The first person to send the correct answer gets his/her name on top of the list!
We do not discourage differential diagnosis. But all the differentials must satisfy the findings noted in the case.
If you feel you have answered rightly but cannot find your name in the above list, please call 09551942599.
Did you Know?
The order in which the names appear in this winner's list is based on the time of submission. The first person to send the correct answer gets his/her name on top of the list!