Newcastle Nuffield Hospital, Newcastle upon Tyne, UK.
Nuffield Department of Orthopaedics, Rheumatology, and Musculoskeletal Sciences, University of Oxford, Oxford, OX3 7LD, UK.
Int Orthop. 2022 Jun;46(6):1375-1380. doi: 10.1007/s00264-022-05341-0. Epub 2022 Feb 19.
Post-void residual (PVR) scans of less than 200 ml are increasingly being used to rule out the likelihood of cauda equina syndrome (CES) and to delay emergency MRI scanning in suspected cases. This study was done to review a series of 50 MRI confirmed cases of CES and to test the hypothesis that a PVR of less than 200 ml was unlikely to be present.
Fifty consecutive medicolegal cases involving CES were audited. Records were reviewed to see if PVR scans were done. MRI scans were reviewed, clinical and radiological diagnosis reviewed, and treatment recorded.
Out of 50 CES cases, 26 had had PVR scans. In 14/26 (54%) the PVR scan was ≤ 200 ml. In one case, the CES diagnosis was in question leaving 13/26 (50%) cases where there was a clear clinical and MRI diagnosis of CES despite the PVR being ≤ 200 ml. All 13 were classified as incomplete cauda equina syndrome (CESI) and all proceeded to emergency decompression.
This study is the first in the literature to demonstrate that there is a significant group of CES patients who require emergency decompression but have PVRs ≤ 200 ml. The results demonstrate the existence of a significant group of CESI patients whose bladder function may be deteriorating, but they have not yet reached the point where the PVR is over 200 ml. Given the accepted understanding that CESI is best treated with emergency decompression, such patients are likely to have worse outcomes if MRI scanning and therefore surgery is delayed. We recommend the following: PVR is recommended as an assessment tool in suspected CES. A PVR of ≤ 200 reduces the likelihood of having CES but does not exclude it; clinical suspicion of CES should always lead to an MRI scan. Further investigation of PVR as a prognostic tool is recommended.
残余尿（PVR）少于 200 毫升的扫描越来越多地被用于排除马尾综合征（CES）的可能性，并在疑似病例中延迟紧急磁共振成像（MRI）扫描。本研究旨在回顾一系列 50 例经 MRI 证实的 CES 病例，并验证 PVR 少于 200 毫升不太可能存在的假设。
对 50 例连续的涉及 CES 的法医案例进行审核。审查记录以确定是否进行了 PVR 扫描。回顾 MRI 扫描、临床和放射学诊断，并记录治疗情况。
在 50 例 CES 病例中，有 26 例进行了 PVR 扫描。在 26 例中有 14 例（54%）PVR 扫描量≤200 毫升。在一例中，CES 诊断存在疑问，这使得在 26 例中有 13 例（50%）存在明确的 CES 的临床和 MRI 诊断，尽管 PVR 量≤200 毫升。所有 13 例均被归类为不完全性马尾综合征（CESI），所有患者均进行了紧急减压。
本研究首次在文献中证明，有相当一部分 CES 患者需要紧急减压，但 PVR 量≤200 毫升。结果表明存在相当一部分 CESI 患者，他们的膀胱功能可能正在恶化，但尚未达到 PVR 超过 200 毫升的程度。鉴于公认的 CESI 最好通过紧急减压治疗，因此如果 MRI 扫描和手术延迟，此类患者的预后可能更差。我们建议：PVR 推荐作为疑似 CES 的评估工具。PVR 量≤200 可降低 CES 的可能性，但不能排除；对 CES 的临床怀疑应始终导致 MRI 扫描。建议进一步研究 PVR 作为预后工具。
