Pe. Helkjaer et al., THERMAL ARTIFACTS AND INTER-GYNECOLOGIST VARIATION OF LASER CONE BIOPSIES OF THE CERVIX, Obstetrics and gynecology, 82(3), 1993, pp. 435-439
Objective: To evaluate the extent of thermal artifacts and the inter-g
ynecologist variation in CO, laser cone biopsies for cervical intraepi
thelial neoplasia (CIN) using high power density. Methods: All 1180 hi
stologic sections from 93 CO2 laser cone biopsies performed by nine gy
necologists were evaluated by morphometry. Power density of 19,700 W/c
m2 and spot size of 0.43 mm were used. The lengths of different epithe
lia, the distance from CIN to the excision margins, the thermal artifa
cts, and the extension of denudation were analyzed. Mean values and st
andard deviations were analyzed for all indices. The inter-gynecologis
t variation was analyzed using one-way analysis of variance, Tukey-Kra
mer Honestly Significant Difference test, and chi2 contingency table a
nalysis regarding cones classified as ''good'' or ''not good.'' Result
s: The mean length of analyzed surface per cone was 134 mm. In 3% of t
he sections, the sum of artifacts at the external excision margin exce
eded the average ''minimum free distance'' from CIN to the margin (2.8
8 mm). At the endocervical excision margin, the free distance was exce
eded in 17% of the sections. Eighteen percent of the cones had CIN at
the excision margins, with no significant differences between gynecolo
gists (P = .83). Differences existed between gynecologists regarding f
ree minimum distance and minor thermal artifacts at the external margi
n, but when clinically relevant groups were applied, no significant di
fferences were found (P > .05). Conclusion: We found that a high power
density at CO2 laser cone biopsy resulted in specimens with minimal t
hermal artifacts compared to other authors who used low power density.
No clinically relevant differences were found between the gynecologis
ts regarding free margins or artifacts.