Salvage operation for persistent low back pain and sciatica induced by percutaneous laser disc decompression performed at outside institution: correlation of magnetic resonance imaging and intraoperative and pathological findings.

OBJECTIVE: We identified several problems associated with percutaneous lumbar disc decompression (PLDD) based on a study of patients who required salvage operations for complications after undergoing PLDD at an outside institution. BACKGROUND DATA: PLDD has been performed as a new treatment for intervertebral disc herniation in recent years, and its safety and effectiveness are in the process of being established. Because the procedure is simple to perform under local anesthesia, inappropriate irradiation and application to patients for whom it is not indicated have sometimes resulted in a poor outcome and serious complications. METHODS: The patients comprised 10 with lumbar disc herniation and three with lumbar spondylolisthesis. We analyzed the magnetic resonance (MR) imaging and operative findings as well as the pathological features of surgically obtained disc specimens and studied their relationships with the clinical outcomes of the operations. RESULTS: Initial examination of all patients at our hospital showed that PLDD had no effect on low back pain or sciatica. In patients who showed MR signal changes in the end-plate, the pathological examination revealed extensive necrosis of cartilage and bone. During salvage operations, severe adhesion of herniated masses to nerve roots was often observed, with carbonized disc tissue surrounding the nerve roots and might have their nerve root injured thermally. CONCLUSION: PLDD is associated with significant risk of disc, end-plate, and nerve root injuries, contrary to the general belief that the procedure is minimally invasive. Our findings highlight the need for careful diagnosis and sufficient technical skill when selecting PLDD as a treatment option.

[Effects of nitrendipine on circadian variation of blood pressure in inpatients with renal parenchymal hypertension: assessment by ambulatory blood pressure monitoring].

OBJECTIVE: To study the effect of once-daily administration of a nitrendipine tablet 10 mg on 24-hour ambulatory blood pressure in inpatients with renal parenchymal hypertension. METHODS: Sixteen patients participated in the present study, and one patient was withdrawn because the baseline office blood pressure was less than 140/90 mmHg. In the baseline period, ambulatory blood pressure was monitored every 30 minutes for 30 hours. After the baseline measurement, nitrendipine 10 mg was orally administered once daily every morning for 7 days. The 30-hour ambulatory blood pressure monitoring was repeated after Day 6. RESULTS: Fifteen patients (aged 64.9 +/- 15.0 years) completed the study protocol. Baseline office blood pressure was 157.9 +/- 17.5/84.7 +/- 12.5 mmHg (mean +/- SD). Nitrendipine 10 mg tablets significantly reduced both systolic blood pressure (SBP) and diastolic blood pressure (DBP) at least for 11 hours after administration compared with those at baseline. The rate of "Decrease" (reduction in blood pressure > or = 20/10 mmHg and/or achieved blood pressure < 140/90 mmHg at trough point) was 60.0% (9/15). Eleven patients were considered as effective cases at peak point (maximal reduction in blood pressure > or = 20/10 mmHg). The rate of "Decrease" in effective cases at peak point was 72.7% (8/11). CONCLUSION: These results suggest that a once-daily administration of nitrendipine 10 mg tablets is effective for the 24-hour control of blood pressure in patients with renal parenchymal hypertension.