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Diagnosis of Spinal Disease with Ultrafine Flexible Fiberscopes in Patients with Chronic Pain

Study Design. Spinal epidural and subarachnoid spaces were observed with the newly developed fine flexible fiberscopes in 55 patients with chronic pain. Objectives. To evaluate the fiberscopes as diagnostic tools for spinal canal disease. Summary of Background Data. Fine flexible fiberscopes make it possible to visualize the entire length of the spinal subarachnoid space without major complications, and they may be of value for the diagnosis of certain spinal canal diseases. Methods. The epidural and subarachnoid spaces were accessed by fine flexible fiberscopes (Purely Fine [PF] types) in the initial 45 patients and by those equipped with a tip-steering function and a working channel (Medical Science [MS] types) in the later 10 patients, respectively. The procedures were based on those of continuous epidural or subarachnoid block. Results. Normal and abnormal subarachnoid spaces were clearly observed. When the MS types were used, the intended sites of the spinal structures could be more easily approached. In 12 patients, new diagnoses were made (chronic arachnoiditis 9, subarachnoid cyst 2, old subdural hematoma 1) that could not be found by magnetic resonance imaging or computed tomography. Additionally, chronic arachnoiditis was found in 2 patients with spinal trauma. Pathologic changes were confirmed by fiberscopic examination in 16 patients (arachnoiditis 11, spinal trauma 2, arteriovenous malformation 2, subarachnoid cyst 1). No pathologic changes could be detected in 27 patients with spinal canal stenosis, disc herniation, reflex sympathetic dystrophy, or posttraumatic pain syndrome. There were no significant differences in incidence of new diagnoses between the PF and MS types of fiberscopes. There were no major complications. There were 2 cases of light fever in the initial 10 patients and 7 cases of headache in the initial 14 patients. Only 4 cases of headache were observed in the subsequent 41 patients, in whom 20 mL of saline was injected into the epidural space. Conclusion. These fine flexible fiberscopes may provide new diagnostic and interventional tools for spinal canal diseases, provided skilled techniques are applied.