Falloposcopic observations of endotubal isthmic plugs as a cause of reversible obstruction and their histological characterization.

Eighty falloposcopies were performed in fallopian tubes of women with suspected tubal disease. In three falloposcopies (4%), isthmic plugs were observed occluding the entire isthmic lumen. In all cases these plugs were mobilized by falloposcopic-directed, selected tubal cannulation and aquadissection techniques. Restoration of tubal patency, verified by concurrent chromopertubation under laparoscopic monitoring was achieved in all cases. On one occasion, the isthmic plug was mobilized and identified on the fimbria, and tubal patency was confirmed. When this plug was retrieved and examined histologically, it was found to consist of a cast of debris containing aggregates of histiocyticlike cells of endometrial stromal or mesothelial origin. The genesis of these plugs is unknown. In another subgroup, white to yellow mucus like fragments were observed within the intramural and isthmic lumen during a further 8 of 80 falloposcopies (10%). Whether these mucus like fragments are of physiological or pathophysiological significance remains to be determined. Objective demonstration that isthmic plugs can cause reversible proximal tubal obstruction (PTO) has been achieved using falloposcopy. Falloposcopy offers the diagnostician the ability to objectively classify the cause of PTO. A useful falloposcopic classification and scoring system of tubal lumen lesions has been utilized and is described.