Feasibility of Navigable Percutaneous Disk Decompressor (L'DISQ-C) for Cervical Disk Herniation

Objective To assess the procedural efficacy and safety of a Navigable Percutaneous Disk Decompressor (L'DISQ-C) for cervical disk herniation. Methods We performed intradiskal decompression on cervical spine specimens from five human cadavers using the L'DISQ-C under C-arm fluoroscopic guidance. We evaluated our success for positioning the navigable wand tip into the target region and recorded temperature variation at various distances from the wand tip in the cervical nucleus pulposus. The histologic effect of plasma decompression was examined microscopically using harvested tissues adjacent to the procedure site. Results We successfully navigated the tip of the L'DISQ-C into the target region of the posterior cervical disks on the first insertion attempt in all C3–C4 to C6–C7 disks and in 50% of the C2–C3 and C7–T1 disks. The average temperature elevations within the nucleus pulposus ranged from 4.14 ± 0.08°C to 12.17 ± 0.76°C at various distances from the wand tip with or without saline infusion. A histologic examination showed only minor denaturation at the marginal border of the procedure tract. Conclusion We effectively navigated the L'DISQ-C wand tip into the posterior target region of six cadaveric cervical disks and performed percutaneous resection of the target disk tissues without significant thermal or structural damage to adjacent tissues.

The Effect of Silver Nitrate on Nasal Septal Cartilage

Epistaxis from the anterior septum is frequently treated with a topical application of silver nitrate, which cauterizes the bleeding vessel. However, this treatment causes a septal perforation in a small percentage of patients. We report our study of the histologic effect of topical silver nitrate on samples of septal tissue obtained from 11 patients. We found that 30 seconds of exposure allowed silver nitrate to penetrate to a depth of approximately 1 mm. Longer exposure (45 and 60 sec) resulted in no significant additional penetration. Similarly, the amount of silver nitrate deposition into the chondrocytic lacunae did not vary significantly with the length of exposure. On the other hand, the depth of deposition into the extracellular matrix was positively associated with the duration of exposure. We found no direct evidence that silver nitrate exerted any damaging effect on septal cartilage. Instead, the development of septal perforations in patients who receive topical silver nitrate may be attributable to necrosis of the septal cartilage following damage to the overlying perichondrium, from which it derives its blood supply.