Muscle Flap Treatment of Symptomatic Sacral Meningeal Tarlov Cysts
Mary H. McGrath, MD MPH, Philip R. Weinstein, MD.
University of California San Francisco, San Francisco, CA, USA.
PURPOSE: Tarlov sacral meningeal cysts are pathological intraspinal cysts with spinal nerve root fibers within the cyst wall and cavity. Communicating with the subarachnoid CSF, they can erode the sacrum producing nerve root compression with severe progressive radicular pain, paresthesias, and bowel and bladder dysfunction. Neurosurgeons have not been successful treating the Tarlov cyst. The cysts recur after aspiration, lumbar CSF drainage, and lumboperitoneal shunting. Results are equally poor with neurosurgical cyst resection, decompressive laminectomy, and cyst cauterization or fenestration and closure. This paper describes a new combined neurosurgical / plastic surgical approach that corrects these previously unrepairable defects.
METHODS: Our technique involves laminectomy with partial resection of the posterior cyst wall and the introduction of a deep muscle pedicle flap to pack the cystic cavity. Deep to the lumbosacral fascia, the multifidus is one of the transverso-spinalis deep muscles of the back that arises from the sacrum and inserts into spinous processes several segments higher. It can be mobilized distally off the sacrum as a superiorly based flap and rotated into the Tarlov cyst to be placed directly on the sacral nerve roots. Present bilaterally, one or both muscles can be used to fill the cystic cavity after the cyst wall is resected. In the cases where there is active communication of the CSF between the cyst with the subarachanoid, the muscle can be used to pack the channel after it is ligated or oversewn. When fenestration and repair of the cyst wall is done, the muscles serve to reinforce the repair by sealing CSF leak points where sutures perforate the cyst membrane.
RESULTS: Twenty-five patients with severe radicular pain and sacral Tarlov cysts ranging from 1.5 to 5.0 cm in size were repaired with either unilateral or bilateral deep spinal muscle flaps up to 12 cm in length. The CSF in the Tarlov cysts was in two way communication with the spinal fluid in twelve of the cases. Followed for up to six years and no less than one year, only one patient has had recurrence of radicular symptoms and residual or recurrent cyst formation.
CONCLUSION: We are optimistic that muscle flap obliteration of giant sacral Tarlov meningeal cysts will prevent recurrence and CSF leakage making it possible for the first time to treat these complex and debilitating lesions.