ORLANDO – Narrow band imaging detects neovascularization associated with endometriosis and can be a useful adjunct to laparoscopic white light evaluation, a prospective cohort trial of 53 women with pelvic pain suggested.
The women in the study had no deep infiltrating endometriosis on preoperative ultrasound. Investigators then conducted a standard laparoscopic survey of the pelvis with white light to identify areas of suspected superficial endometriosis, followed by secondary analysis with narrow band imaging.
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In the group of 32 patients, follow-up biopsy results confirmed endometriosis in 24 women, including 7 who also had lesions detected by narrow band imaging. Six of these seven were positive for endometriosis on histology. The women were enrolled in the study from September 2014 to October 2015.
“We found that the [narrow band imaging] is useful in detecting additional areas in patients who had histopathology-proven endometriosis,” said Tony J. Ma, MBBS, a fellow at Mercy Hospital for Women in Melbourne.
In the group of 21 women with no white light lesions, narrow band imaging detected four suspicious lesions. However, these four were not positive for endometriosis.
Narrow band imaging is a mixture of blue and green light, opposite of red color. “It causes blood vessels to be more visually prominent,” Dr. Ma said at the meeting sponsored by AAGL. White light laparoscopy for detection of endometriosis “is the gold standard … but depends on experience of [the] surgeon and severity of the disease.”
These findings support those of a 2008 study that reported a high detection rate of lesions with narrow band imaging, Dr. Ma said. In this earlier prospective cohort study of 20 women, 7 patients with endometriosis who had been ruled out by white light evaluation had a positive histologic finding with narrow band imaging (J Minim Invasive Gynecol. 2008 Sep-Oct;15[5]:636-9).
“Narrow band imaging is a simple, noninvasive adjunct that can assist in the identification of additional sites of endometriosis at laparoscopy,” Dr. Ma said. “The shortened depth of field with narrow band imaging requires the operator to inspect the surface quite closely.”
The study topic is an important one because endometriosis is such a challenge to diagnose and treat, said study discussant Sawsan As-Sanie, MD, a minimally invasive gynecologic surgeon at the University of Michigan, Ann Arbor. She estimated that with the current approach – visualization by white light followed by histopathology – “about 50%-70% of patients we think have endometriosis ultimately do.”
But several unanswered questions remain, Dr. As-Sanie said, such as whether the narrow band imaging findings are clinically relevant and whether they will lead to improved patient outcomes.
“We don’t know the answer yet,” she said. “The end game is really only relevant if we improve patient outcomes.”
Dr. Ma reported having no relevant financial disclosures.