In a reproductive-aged patient who has had a bilateral salpingo-oophorectomy, with or without a hysterectomy, for severe endometriosis or PID, chronic pelvic pain may be caused by ovarian remnant syndrome. This syndrome results from residual ovarian cortical tissue that is left in situ after a difficult dissection in an attempt to perform an oophorectomy. This tissue can become encased in adhesions and result in painful cysts. Often, the patient had multiple pelvic operations with the uterus and adnexa removed sequentially. Laparoscopic oophorectomy, combined with a difficult dissection, is a strong risk factor.
Residual ovary syndrome is uncommon considering the number of women undergoing hysterectomy with ovarian preservation. Theoretically, after a hysterectomy with one or both ovaries intentionally left in situ, adhesions develop and encase the ovaries, then cyclical expansion of the ovaries can result in pain and, in some cases, a tender persistent mass.
The patient usually reports lateralizing pelvic pain, often cycling with ovulation or the luteal phase that is described as sharp and stabbing or constant, dull, and nonradiating, occasionally with associated genitourinary or gastrointestinal symptoms. Symptoms tend to arise 2 to 5 years after initial oophorectomy. A tender mass in the lateral region of the pelvis is pathognomonic. The patient may report deep dyspareunia, constipation, or ﬂank pain.
Ultrasonography usually confirms a mass with the characteristics of ovarian tissue. The accuracy of ultrasound can be improved by treating the patient with a 5-to 10-day course of clomiphene citrate, 100 mg daily, to stimulate follicular development. In a patient who has had bilateral salpingo-oophorectomy and is not taking hormone therapy,estradiol and follicle-stimulating hormone (FSH) assays reveal a characteristic premenopausal picture (FSH <40 mIU/mL and estradiol >20 pg/mL), although on occasion the remaining ovarian tissue may not be active enough to suppress FSH levels (98). The patient may have a persistent estrogenized state based on the vulvar and vaginal examination and lack postmenopausal symptoms such as hot ﬂashes, night sweats, and mood changes. Medical therapy that suppresses ovarian function can be diagnostic and therapeutic.
Initial medical treatment with high-dose progestins or oral contraceptives usually provides good results. Patients also experience pain relief with a GnRH agonist, although these medications are impractical for long-term therapy. Those who achieve relief with GnRH agonists also experience relief with subsequent surgery (99). Laparoscopic examination usually is not productive because the ovarian mass may be missed or adhesions may prevent accurate diagnosis. A few articles documented successful laparoscopic treatment of this condition (100,101). Removal of the remnant ovarian tissue is necessary for treatment, and the corrective surgery tends to be arduous, with risks of cystotomy, enterotomy, and postoperative small bowel obstruction (98). Surgical pathology usually reveals the presence of ovarian tissue, sometimes with endometriosis, corpus lutea or follicle cysts, and fibrous adhesions. Clomiphene citrate can be used 7 to 10 days before surgery to induce folliculogenesis, allowing ovarian tissue to be more easily detected.