BACKGROUND: Rarely, a symptomatic discal pseudocyst can develop after discectomy. Only very recently one clinical article and one case report about this type of pseudocyst were published: Kang and Park (J Korean Neurosurg Soc 49(1):31-36, 2011); Young PM, Fenton DS, Czervionke LF (Spine J. 9(2):e9-e15, 2009). Here, in an attempt to more clearly discriminate this peculiar cyst, the authors retrospectively report the clinical, radiological, and histological findings in 12 symptomatic patients with cystic lesions attached to an operated disc. METHODS: From January 2007 to May 2010, 12 patients who experienced recurrent symptoms after successful lumbar discectomy were diagnosed with postoperative discal pseudocyst (PDP). After discectomy, the mean time to relapsing radiculopathy was 23.3 days (range, 9-38 days) with a mean of 6.8 ± 1.3 on the visual analogue scale (VAS). PDPs were detected on magnetic resonance imaging (MRI) at 31.2 days (range, 14-60 days) after the initial surgery. Of these 12 patients, 6 were treated conservatively (group C) and 6 by surgery (group S). RESULTS: In the six patients in group C, the mean duration of relapsing pain was 77.8 days (range, 20-225 days), and near total or total regression of the cyst was detected at a mean of 82.7 days (range, 23-240 days) after initial detection by MRI. Time to spontaneous regression of PDP varied widely. In the six patients in group S, surgical treatment was administered within a few days of MRI diagnosis and achieved successful pain relief. CONCLUSIONS: Postoperative discal pseudocyst appears to develop after lumbar discectomy and can regress spontaneously.
BACKGROUND: Rarely, a symptomatic discal pseudocyst can develop after discectomy. Only very recently one clinical article and one case report about this type of pseudocyst were published: Kang and Park (J Korean Neurosurg Soc 49(1):31-36, 2011); Young PM, Fenton DS, Czervionke LF (Spine J. 9(2):e9-e15, 2009). Here, in an attempt to more clearly discriminate this peculiar cyst, the authors retrospectively report the clinical, radiological, and histological findings in 12 symptomatic patients with cystic lesions attached to an operated disc. METHODS: From January 2007 to May 2010, 12 patients who experienced recurrent symptoms after successful lumbar discectomy were diagnosed with postoperative discal pseudocyst (PDP). After discectomy, the mean time to relapsing radiculopathy was 23.3 days (range, 9-38 days) with a mean of 6.8 ± 1.3 on the visual analogue scale (VAS). PDPs were detected on magnetic resonance imaging (MRI) at 31.2 days (range, 14-60 days) after the initial surgery. Of these 12 patients, 6 were treated conservatively (group C) and 6 by surgery (group S). RESULTS: In the six patients in group C, the mean duration of relapsing pain was 77.8 days (range, 20-225 days), and near total or total regression of the cyst was detected at a mean of 82.7 days (range, 23-240 days) after initial detection by MRI. Time to spontaneous regression of PDP varied widely. In the six patients in group S, surgical treatment was administered within a few days of MRI diagnosis and achieved successful pain relief. CONCLUSIONS:Postoperative discal pseudocyst appears to develop after lumbar discectomy and can regress spontaneously.