Histological Characterization of Vaginal Cuff Tissue Using Different Energy Sources During Robotic Hysterectomy

Vaginal cuff dehiscence, a rare complication of gynecologic surgeries, can be devastating,
particularly when associated with bowel evisceration. A review of records from 1970 - 2001
at the Mayo Clinic in Rochester, MN revealed a low incidence (0.032%) of vaginal cuff
dehiscence after pelvic operation via both abdominal and vaginal approaches3. At a single,
large, tertiary care facility, total laparoscopic hysterectomy (TLH) was associated with an
increased incidence of vaginal cuff dehiscence compared to other approaches (4.93% vs. 0.29%
TVH, and 0.12% TAH)1. A review of our robotic experience revealed a vaginal cuff dehiscence
incidence of 4.1%, which is comparable to the previously reported incidence for TLH2. An
increasing number of laparoscopic hysterectomies are being performed in the United States
with the rate of laparoscopic procedures increasing from 0.3% in 1990 to 11.8% in 20034.
With 11.8% of 600,000 annual hysterectomies being performed via the laparoscopic route in
the United States, there would be an estimated 3,400 cases of vaginal cuff dehiscence per
year.

The cause of the higher rate of vaginal cuff dehiscence in both laparoscopic and robotic
hysterectomies is currently unknown. One of the major differences between the laparoscopic
and robotic approach as compared to the vaginal/abdominal route is the method by which the
cervix is amputated from the vagina. With the vaginal and abdominal approaches, a colpotomy
is made sharply with a knife or scissors. In contrast, the colpotomy is performed with
electrocoagulation with the laparoscopic and robotic routes. One theory to explain the
increased dehiscence incidence is the lateral thermal effects of electrocoagulation on the
vaginal cuff which may adversely affect tissue healing.

This study aims primarily to shed light on the etiology of vaginal cuff healing after a
robotic total hysterectomy. This will be done by comparing the extent of thermal injury at
the cellular level using monopolar vs CO2 laser at the time of the colpotomy.