How to treat cesarean scar defect by hysteroscopy
Dr. Luis Alonso Pacheco
The hysteroscopic surgical isthmocele correction technique consists of four steps following Gubbini’s recommendation. As previously mentioned, the difference with the technique proposed by Fabres lies in the resection of both the lower and upper fibrous arch.
The surgical technique is usually performed with resectoscopes of 26-27 fr after dilation of the cervical canal. Many authors prefer the use of smaller resectors or even mini-resectors that do not require prior cervical dilation. By not performing a previous cervical dilation, the normal anatomy of the isthmocele is not altered, better identifying the defect in its natural state without creating any artifact in the anatomical structures.
The steps to follow to perform an Ithmocele repair are the following:
1- Resection of the lower fibrous arch. The resection of this fibrous tissue that is responsible for the natural exit of the menstrual flow is performed. This anterior arc must be resected until the continuity of the anterior face is restored, making the defect flat, allowing visualization the isthmocele dome. By resecting this fibrous tissue, we prevent the isthmocele from acting as a reservoir of postmenstrual blood.
2- Resection of the posterior arch. Resecting the posterior arch reduces fibrous retraction and improves uterine contractility, a very important factor in cleaning the uterus after menstruation.
3- Superficial coagulation of the vessels at the bottom of the isthmocele. The objective is to reduce the production of menstrual blood and debris in situ derived from the inflammation and vascular fragility found at the bottom of the isthmocele. We must remember that deep coagulation should not be performed given the proximity of the bladder with this area of the isthmocele dome. Some authors advise the instillation of methylene blue in the bladder, which would alert us in the case of perforation of the bladder.
4- Total 360º endocervical ablation. Electrofulguration of all the inflammatory tissue that is located around the defect in the lateral aspect and posterior at the isthmic level. The objective of this step is that by destroying this inflammatory tissue, a substitution of the same with a new epithelial tissue occurs.
The hysteroscopic correction technique is simple and it is really a minimally invasive approach for the patient. There is currently a consensus on choosing the hysteroscopic route when the thickness of the residual myometrium is greater than 3 mm, which provides a margin of safety to avoid uterine perforation with possible bladder injury.