Isthmocele: the “hot air balloon sign”, a gynecological consequence of an obstetric intervention

Caesarean section is the most common surgical procedure for women of childbearing age [
1
  • Menacker F
  • Declercq E
  • Macdorman MF.
Cesarean delivery: background, trends, and epidemiology.

]. Sometimes the healing of the hysterotomy incision leaves areas of loss of myometrial continuity creating pocket-like defects known as an isthmocele. These defects function as a reservoir collecting menstrual blood generating postmenstrual bleeding, pelvic pain, dyspareunia, and secondary infertility, among other symptoms. [

2
  • Setubal A
  • Alves J
  • Osório F
  • et al.
Treatment for uterine isthmocele, a pouchlike defect at the site of a cesarean section
scar.

]. Saline infusion ultrasound is an effective imaging modality [

3
  • Monteagudo A
  • Carreno C
  • Timor-Tritsch IE.
Saline infusion sonohysterography in nonpregnant women with previous cesarean delivery:
the “niche” in the scar.

]. Surgical and non-surgical options have been recommended for the treatment of patients with symptomatic isthmocele [

4
  • Vitale SG
  • Ludwin A
  • Vilos GA
  • et al.
From hysteroscopy to laparoendoscopic surgery: what is the best surgical approach
for symptomatic isthmocele? A systematic review and meta-analysis.

]. Different surgical approaches, including abdominal (laparoscopic, robotic, or laparotomy), vaginal, hysteroscopic, and combined techniques have been proposed; however, neither approach seems superior to the other [

2
  • Setubal A
  • Alves J
  • Osório F
  • et al.
Treatment for uterine isthmocele, a pouchlike defect at the site of a cesarean section
scar.

]. We report the case of a 31-year-old patient Gravida 1 Para 1 who underwent a caesarean section at 38 weeks because of a lack of progression with stoppage of labor at 7 cm of cervical dilatation. Five months after delivery, she resumed menstruation with the presence of postmenstrual spotting lasting 7-12 days. Initially, she was treated with oral contraceptives, but the symptoms persisted. Ultrasound revealed the presence of a large pocket-like defect at the caesarean section scar (Fig. 1). The residual thickness of the myometrium was 1 mm. Laparoscopic isthmoplasty was performed. After dissecting the bladder from the lower uterine segment, an unusually large pouch defect was noted on the lower uterine segment. Transillumination and fluid distention with hysteroscopy swollen the defect mimicking a hot air balloon – “the hot air balloon sign” (Fig. 2). Laparoscopic excision of the defect was performed with closure using the 0-Vicryl interrupted figure-of-8 suture technique (Fig. 3). The patient had an uneventful postoperative recovery and complete resolution of her symptoms. Isthmocele formation is a potential late complication of caesarean section. Its presence should be considered in patients with a history of Caesarean section surgery presenting with postmenstrual spotting.

Fig. 1Hysteroscopic view of the lower uterine segment showing the superior cavity (isthmocoele) and the uterine cavity (below).

Figure 2

Figure 2Laparoscopic view of the isthmocele. Appreciate the large size of the sac which is transilluminated by simultaneous hysteroscopic visualization.

Figure 3

Figure 3Longitudinal uterine section of the ultrasound revealing the large dimension of the isthmocele. Note the large size of the myometrial defect communicating the cavity of the isthmocele and the cervical canal.