Precise Monitoring of Returning Sensation in Digital-Nerve Lesions by Three-Dimensional Imaging: A Proof-of-Concept Study.

SUMMARY: Digital-nerve lesions result in a loss of tactile sensation reflected by an anesthetic area (AA) at the radial or ulnar aspect of the respective digit. Available tools to monitor the recovery of tactile sense have been criticized for their lack of validity. Precise quantification of AA dynamics by three-dimensional (3D) imaging could serve as an accurate surrogate to monitor recovery after digital-nerve repair. For validation, AAs were marked on digits of healthy volunteers to simulate the AA of an impaired cutaneous innervation. The 3D models were composed from raw images that had been acquired with a 3D camera to precisely quantify relative AA for each digit (3D models, n = 80). Operator properties varied with regard to individual experience in 3D imaging and image processing. In addition, the concept was applied in a clinical case study. Results showed that images taken by experienced photographers were rated as better quality ( P < 0.001) and needed less processing time ( P = 0.020). Quantification of the relative AA was not altered significantly, regardless of experience level of the photographer ( P = 0.425) or image assembler ( P = 0.749). The proposed concept allows precise and reliable surface quantification of digits and can be performed consistently without relevant distortion by lack of examiner experience. Routine 3D imaging of the AA has the great potential to provide visual evidence of various returning states of sensation and to convert sensory nerve recovery into a metric variable with high responsiveness to temporal progress.

Functional outcome after surgical treatment of spinal meningioma.

OBJECTIVE: Space-occupying spinal meningiomas (SM), commonly diagnosed due to gradual neurological deterioration, are treated surgically by decompression and tumor resection. In this series of patients with surgically treated SM, we determined individual predictors of functional outcome in the context of intraoperative neuromonitoring (IOM). METHODS: This retrospective study included 45 patients (39 women, 6 men; mean age 63 years). We reviewed pre- and postoperative charts, surgical reports, radiographic data for demographics, use of IOM, duration of symptoms, histopathology, co-morbidities, radiographic extension, surgical strategy, neurological performance (Japanese Orthopedic Association Score [JOA score]. Median follow-up was 34 months (12-190 months). RESULTS: Most frequent surgical approaches were laminectomy (71.1%, n = 32) and hemi-laminectomy (28.9%, n = 13). Predominant SM site was the thoracic spine (55.6%, n = 25). Most common symptoms were sensory deficits (77.8%, n = 35), gait disorders (55.6%, n = 25), motor deficits (42.2%, n = 19), and radiating pain (37.8%, n = 17). Simpson grade 1 resection was achieved in 6 patients, most common type of resection was Simpson grade 2 in 36 patients. During follow-up, 80.0% of patients had fully recovered sensory deficits (p < 0.001), 76.0% of patients with preoperative gait disorders had been asymptomatic (p < 0.001), and motor deficits in 12/19 (63.1%). Pain had decreased significantly from admission to follow-up (p = 0.001). IOM was used in 20 (44.4%) patients. Postoperatively, 6(13.3%) patients had developed a new neurological deficit, 4 of them operated without IOM. CONCLUSION: Resection of SM with IOM showed good recovery, excellent functional results with low surgical morbidity.