Syringomyelia caused by an arachnoid web in a patient with shunted Dandy-Walker malformation.
BACKGROUND
Dandy-Walker malformation (DWM) is a congenital brain anomaly characterized by dysgenesis of the cerebellar vermis and the presence of a posterior fossa cyst. The association of syringomyelia with DWM is extremely rare.


METHODS
A 10-year-old patient who was diagnosed with DWM in infancy presented with progressive scoliosis and fecal incontinence. He had been treated with cystoventriculoperitoneal shunting with a Y-connection during infancy, which was followed by a revision 6 years later. During the revision surgery, intraventricular bleeding occurred and was managed conservatively. Imaging studies for the current visit revealed syringomyelia along the cervicothoracic spinal cord and a membranous structure around the cervicomedullary junction. Phase-contrast cine magnetic resonance imaging (MRI) revealed disturbed cerebrospinal fluid (CSF) flow across the membrane. We excised the arachnoid web that was tethering the brainstem and blocking CSF flow. Postoperatively, the patient experienced symptom relief, and the follow-up imaging study demonstrated a dramatic decrease in the size of the syringomyelia.


CONCLUSIONS
We suggest that syrinx formation in this patient was possibly caused by disturbed CSF flow and tethering of the brainstem.


CONCLUSIONS
We experienced an unusual case of DWM with syringomyelia which was caused by an arachnoid web blocking CSF flow and tethering the brainstem. The arachnoid web seems to be formed by previous bleeding which occurred at the time of shunt revision. After excision of the arachnoid web, the patient showed good outcome.
Division of Pediatric Neurosurgery, Department of Neurosurgery, Seoul National University Children's Hospital and Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-744, Republic of Korea.
Hee Chang
HC
Lee
Division of Pediatric Neurosurgery, Department of Neurosurgery, Seoul National University Children's Hospital and Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-744, Republic of Korea.
Jung Won
JW
Choi
Division of Pediatric Neurosurgery, Department of Neurosurgery, Seoul National University Children's Hospital and Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-744, Republic of Korea.
Ji Yeoun
JY
Lee
Division of Pediatric Neurosurgery, Department of Neurosurgery, Seoul National University Children's Hospital and Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-744, Republic of Korea.
Ji Hoon
JH
Phi
Division of Pediatric Neurosurgery, Department of Neurosurgery, Seoul National University Children's Hospital and Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-744, Republic of Korea.
Seung-Ki
SK
Kim
Division of Pediatric Neurosurgery, Department of Neurosurgery, Seoul National University Children's Hospital and Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-744, Republic of Korea.
Byung-Kyu
BK
Cho
Division of Pediatric Neurosurgery, Department of Neurosurgery, Seoul National University Children's Hospital and Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-744, Republic of Korea. kcwang@snu.ac.kr.
Kyu-Chang
KC
Wang
D001099:Arachnoid / Q000000981:diagnostic imaging / Q000601:surgery*; D001166:Arteriovenous Shunt, Surgical / Q000009:adverse effects*; D002648:Child; D003616:Dandy-Walker Syndrome / Q000000981:diagnostic imaging / Q000601:surgery*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D011183:Postoperative Complications / Q000503:physiopathology*; D013595:Syringomyelia / Q000000981:diagnostic imaging / Q000209:etiology*
Arachnoid web; Dandy-Walker malformation; Membrane excision; Syringomyelia