Hysteroscopy, as the name suggests (hystero = uterus; scopy = to see), is a surgical procedure in which a telescope is inserted inside the uterus to examine the uterine lining. This procedure can assist in the diagnosis of various uterine conditions which can cause infertility, such as:
- submucous (internal) fibroids
- scarring (adhesions or synechiae)
- endometrial polyps
- uterine septa and other congenital malformations
Before performing hysteroscopy, a hysterosalpingogram (an x-ray of the uterus and fallopian tubes) may be performed to provide additional information about the cavity which can be useful during surgery. Many doctors will also do a vaginal ultrasound as a diagnostic aid. Diagnostic hysteroscopy is usually conducted on a day-care basis with either general or local anesthesia and takes about thirty minutes to perform.
The first step of hysteroscopy involves cervical dilatation - stretching and opening the canal of the cervix with a series of dilators. Once the dilatation of the cervix is complete, the hysteroscope, a narrow lighted telescope, is passed through the cervix and into the lower end of the uterus. A clear solution (Hyskon or glycine) or carbon dioxide gas is then injected into the uterus through the instrument. This solution or gas expands the uterine cavity, clears blood and mucus away, and enables the surgeon to directly view the internal structure of the uterus.
The doctor systematically examines the lining of the cervical canal; the lining of the uterine cavity; and looks for the internal openings of the fallopian tubes where they enter the uterine cavity - the tubal ostia.
Some doctors may do a curettage (a surgical scraping of the inside of the uterine cavity) after the hysteroscopy and send the endometrial tissue for pathologic examination.
The technique of hysteroscopy has also been expanded to include operative hysteroscopy. Operative hysteroscopy can treat many of the abnormalities found during diagnostic hysteroscopy at the time of diagnosis.
The procedure is very similar to diagnostic hysteroscopy except that operating instruments such as scissors, biopsy forceps, electocautery instruments, and graspers can be placed into the uterine cavity through a channel in the operative hysteroscope. Fibroid tumors, scar tissue (synechiae or adhesions), and polyps can be removed from inside the uterus. Congenital abnormalities, such as a uterine septum, may also be corrected through the hysteroscope.
In this video, you can watch Dr Anjali Malpani perform an operative hysteroscopy, in which she performs an adhesiolysis to remove intrauterine adhesions to treat Asherman syndrome
This is what the surgeon does and sees on the video screen when actually performing an operative hysteroscopic adhesioloysis.
A relatively new method for treating proximal tubal obstruction (cornual blocks, where the tubes are blocked at the utero-tubal junction) is that of hysteroscopic tubal cannulation. Many studies have shown that this kind of block is often because of mucus plugs or debris which plug the tubal lining at the uterotubal junction which is as thin as a hair. It is now possible to pass a fine guidewire through the hysteroscope into the tubes, and thus remove the plug or debris and open the tubes - thus restoring normal tubal patency with "minimally invasive surgery"!
Another advance has been the development of the method of falloposcopy - in which a very fine flexible telescope is passed into the tube through the hysteroscope, so as to visualize the interior of the entire tube.
After a hysteroscopy, patients often have cramping similar to that experienced during a menstrual period; and some vaginal staining for several days. Regular activities can be resumed within one or two days after surgery. Sexual intercourse should be avoided for a few days or for as long as bleeding occurs.
Complications occur rarely during hysteroscopy. In a few cases, infection of the uterus or fallopian tubes can result. Occasionally, a hole may be made through the back of the uterus - a perforation. However, this is usually not a serious problem because the perforation closes on its own. Frequently, when extensive operative hysteroscopy is planned, diagnostic laparoscopy is performed at the same time to allow the surgeon to see the outside as well as the inside of the uterus to try to reduce the risk of accidental uterine perforation. Other possible complications include allergic reactions and bleeding.
Endometrial or uterine polyps are soft, fingerlike growths which develop in the lining of the uterus (the endometrium). They develop because of excessive multiplication of the endometrial cells, and are hormonally dependent , so that they increase in size depending upon the estrogen level. They can usually be detected on an ultrasound scan if this is done mid-cycle, when estrogen levels are maximal, but are easily missed if the scan is not done at the right time of the menstrual cycle. Polyps are an uncommon but important cause of infertility, because they can easily be removed during hysteroscopic surgery.
Fig 1. Uterine polyp as seen during hysteroscopy
Fig 2. Uterine polyp seen during ultrasound scan after infusion of saline which outlines the polyp in the cavity
While the commonest problem found in the uterus is a fibroid (myoma or leiomyoma), this is rarely a cause of infertility, and is usually an incidental finding of little importance. Fibroids are common benign smooth muscle tumors which arise in the wall of the uterus, and may be single or multiple. About 25% of all women over the age of 35 have fibroids.
Most fibroids develop in the wall of the uterus (intramural ) or protrude outside of the uterine wall (subserous fibroids), and these can usually be left alone, since they do not hinder fertility, and neither do they cause problems during the pregnancy. In fact, unnecessary surgery to remove the fibroid often causes more harm than good. This surgery often creates adhesions, which causes the tubes to get blocked.
However, if the fibroids are very large, they may need surgical removal, and this procedure is called a myomectomy. Some doctors give an injection of a GnRH analog prior to surgery in order to shrink the fibroid and make surgery technically easier. When performed by an expert, it is a safe and effective procedure which can be accomplished with minimal blood loss. However, sometimes because of uncontrollable bleeding the surgeon may be forced to remove the entire uterus (a procedure called a hysterectomy), and this is obviously a disaster for the infertile woman!
The standard technique for removing a fibroid is through open surgery (laparotomy). It is now also possible to remove fibroids through the laparoscope, but laparoscopic myomectomy does not allow for optimal reconstruction of the uterus. Submucous fibroids are an important cause of infertility, because they interfere with implantation of the embryo, by acting as a foreign body. These are best removed by an operative hysteroscopy. While surgery can remove the fibroid, it can recur again, and most doctors advise the patient to try to conceive as soon as possible after surgery.
Fig 2. Schematic showing a submucous fibroid; and a subserous fibroid compressing the right fallopian tube
Fibroids may grow larger during the pregnancy, but usually pregnancy and delivery are uneventful. In rare cases, after a myomectomy, uterine rupture may occur during pregnancy or delivery, and this complication may result in severe blood loss, fetal loss and even maternal death.
Because of the potential for catastrophic results, it is recommended that women have cesarean deliveries in the following circumstances: 1) when the myomectomy involved full-thickness incision of the uterine wall or multiple deep uterine incisions or 2) when myomectomy was complicated by infection which may have weakened the uterine wall or 3) when there is doubt regarding the adequacy or extent of the uterine repair.
The uterus was often a neglected organ in the infertility workup, partly because we did not have the tools to study it properly. Hysteroscopy, hysterosalpingography and vaginal ultrasound are all complementary procedures for evaluating the uterine cavity in the infertile woman. The HSG is good for looking for polyps, adhesions and septa which appear as "filling defects" on the X-ray. However, careful radiologic technique is a must. Vaginal ultrasound is excellent for detecting submucosal fibroids or polyps, which can be missed on hysteroscopy and HSG. Of course, the major advantage of hysteroscopy is it offers the chance of treating the problem as well!
We are now also developing newer techniques to study the uterus. One of our major areas of ignorance today is the complex process of embryo implantation. It is obvious that the endometrium has a key role to play in this process, in which the embryo has to appose and attach itself to the maternal endometrium and invade into it. At present, the tools we have to study endometrial function and receptivity are very crude. They include primarily transvaginal ultrasound, to assess the endometrial thickness and texture, but this provides very limited and indirect evidence of endometrial functions. Colour Doppler ultrasound has also been used to assess endometrial blood flow ( perfusion), but its utility is limited.
Since embryo-endometrium interaction is a biochemical process, a lot of study has been done on the role of the molecules involved in this process. Recent research has shown that the normal endometrium contains various cell adhesion proteins called integrins, which allow the embryo to interact with it. Studies have shown that the endometrium of some infertile women is deficient in some of these integrins, and this deficiency may be responsible for failure of the embryo to implant successfully. Thus, testing the endometrium for beta integrin can be a useful marker for uterine receptivity. This test involves doing an endometrial biopsy at a specific point in the menstrual cycle, and evaluating this with special staining techniques, but is only available on a research basis so far.