## Background and objective: Since 1992, the ho:yag 2100 nm laser has been in regular use in percutaneous lumbar disc surgery through the uniportal approach. in vitro experiments were done to find out the exact amount of ablated tissue in weight per energy used with the present beam delivery system
Quantitative analysis of diurnal variation in volume and water content of lumbar intervertebral discs
β Scribed by Neil Roberts; David Hogg; Graham H. Whitehouse; Peter Dangerfield
- Publisher
- John Wiley and Sons
- Year
- 1998
- Tongue
- English
- Weight
- 206 KB
- Volume
- 11
- Category
- Article
- ISSN
- 0897-3806
No coin nor oath required. For personal study only.
β¦ Synopsis
The Cavalieri method of modern design stereology has been used in combination with magnetic resonance imaging (MRI) to obtain unbiased estimates of the volume of the lumbar intervertebral discs immediately at the end of a day of normal activity and again following a night's rest. In addition, pixel-by-pixel mapping of the T2-relaxation time has been used to characterize objectively the tissues of the intervertebral discs. The mean increase in height of seven female subjects of average age 21 years (range 19-23 years) measured with a stediometer was 19.3 mm (range 8-26 mm). Image analysis showed that the mean overnight increase in volume of lumbar discs was 1300 mm 3 (range 100-2700 mm 3 ). The increase in volume of the disc was accompanied by an increase in the T2-relaxation time of the nucleus pulposus. This suggests that the change in disc volume is most probably caused by a preferential increase in the water content of the nucleus pulposus.
π SIMILAR VOLUMES
Mechanical loading, occurring during normal daily life, causes fluid to be expelled from intervertebral discs. Excessive fluid loss during heavy loading might make the disc more vulnerable to damage. In this study, fluid loss was investigated in vitro through monitoring the loss of MRI signal intens