In:
Journal of Neurosurgery, Journal of Neurosurgery Publishing Group (JNSPG), Vol. 73, No. 4 ( 1990-10), p. 611-614
Abstract:
✓ The 1.9- µ wavelength component of a 1.9/1.06- µ two-wavelength laser with near-continuous wave properties was tested for its potential use in neurosurgery. The 1.9- µ wavelength has tissue-ablative capabilities, while the 1.06- µ wavelength (Nd:YAG) is suitable for achieving hemostasis. The advantages of the 1.9- µ wavelength over the CO 2 laser include its ability to transmit through silica fiberoptic delivery systems and its deeper penetration in water (approximately 100 µ , a depth 10 times greater than for the CO 2 laser), which is compatible with irrigation during ablation. To test the effectiveness of the laser, bilateral craniotomies were performed in anesthetized rats immobilized in a stereotactic frame. Under an operating microscope, lesions were made on the cortex by delivering the 1.9- µ laser beam through a 400- µ fiber at an average power of 1 W over a range of fluences. Subjective intraoperative observations were notable for minimal bleeding, absence of charring when the tissue was irrigated with a thin stream of saline, and uniform lesion formation. For comparison, lesions were generated with a commercially available continuous-wave CO 2 laser at equivalent power and fluences. Histological specimens were divided into three groups based on the study after laser application: acute (30 minutes), subacute (48 hours), and chronic (14 days). The extent of thermal injury for the 1.9- µ laser in the acute lesions was quantitatively and histologically similar to that generated by the CO 2 laser. Regions of injury extended approximately from the apex of the lesion, and crater depths generated by both lasers were similar (250 to 750 µ ) in the range of fluences investigated (1.25 to 10 kJ/sq cm). Subacute and chronic histological specimens demonstrated inflammatory and repair responses that correlated with the acute injury regions in both the 1.9- µ and CO 2 laser-treated specimens. This study demonstrates a neurosurgical potential for a new two-wavelength laser that ablates tissue effectively with limited thermal injury. The 1.9- µ laser is comparable to the widely used CO 2 laser but offers several unique advantages, including the ability for delivery through a fiberoptic system and to irrigate tissue during use.
Type of Medium:
Online Resource
ISSN:
0022-3085
DOI:
10.3171/jns.1990.73.4.0611
Language:
Unknown
Publisher:
Journal of Neurosurgery Publishing Group (JNSPG)
Publication Date:
1990
detail.hit.zdb_id:
2026156-1
