1. Introduction to Endometrial Polyps

Endometrial polyps (EPs) are focal intrauterine lesions that vary in size from a few millimeters to several centimeters are composed of sessile or pedunculated endometrial glands, stroma, blood vessels, and fibrous tissues. EPs may be asymptomatic but may present as abnormal uterine bleeding and/or infertility with a reported prevalence between 6% and 32% ^[1]. Some evidence suggests that EPs have an adverse effect on fertility, and there is an association between hysteroscopic polypectomy and increased rates of natural conception and assisted reproductive treatment ^[1]. As such, the surgical removal of EPs is recommended for those with symptomatic bleeding and infertility ^[2].

2. Hysteroscopic Treatment of Endometrial Polyps

Hysteroscopy with traditional mechanical resection with scissors and/or graspers and the resectoscope is the historical standard for the treatment of the endometrial pathology. However, use of these instruments often require multiple insertions and removal of the hysteroscope and operative instruments, prolonging operative time and increasing difficulty for extensive endometrial pathology.

A game-changer was the electromechanical hysteroscopic tissue morcellator (mHTR). First reported in 2005, Emanuel et al. reported on the device which combines a disposable mechanical cutting device (@$1100 USD) using a rotating tube inside a cutting window that simultaneously resects and aspirates the polypoid tissue into a collection bag ^[3]. This eliminated the need for frequent insertion to remove the tissue. mHTR systems are driven mechanically by an electrically powered control unit and have advantages in that they do not use electrocoagulation and use a physiologic saline solution as distension and irrigation media instead of non-physiologic, electrolyte-free solutions used in monopolar high-frequency resectoscopy. Previous studies demonstrated a significant reduction in operative time using mHTR systems for the removal of polyps and myomas when compared to the resectoscope, with associated low rates of adverse events, high physician acceptance, and significant health-related, quality-of-life improvements following resection. Increasingly, these electromechanical mHTR devices have become widespread for removing intrauterine pathology in both the operating room and office setting. However, while these mHTR devices offer significant advantages, they are often accompanied by high start-up and operating costs including purchasing and maintaining electric control equipment but also indirect costs of installation and commissioning. Together, these factors have limited the world-wide widespread use of electromechanical mHTR systems devices in both the operating room and outpatient settings.

3. Disposable Manual mHTR Device

The manual mHTR device has provided an alternative with an innovative design concept that significantly reduces costs (@$250 USD) while retaining the benefits of electric devices. The single-use equipment design eliminates the need for expensive maintenance and continuous equipment renewal, thereby reducing initial investment costs. Manual mHTR devices also simplify setup and operation procedures, without the more complicated installation and debugging, making the operative process more convenient and reduces the need for training and its associated costs. This makes the manual mHTR an attractive option for the treatment of endometrial lesions.

To our knowledge, there are currently three manual mHTR devices on the market with limited clinical reports detailing the use of these manual devices. These including the MyoSure^® MANUAL device (Hologic™); Resectr™ 9Fr (Minerva Surgical), and the Polygon™ ^[4], and the device distributed as Polygon Medical Devices, Holliston, MA, USA/PolyGone® by OriGyn Medical, Hangzhou, China) Polygon/PolyGone Resection devices.

The latter has only recently become available. Specifically, this manual mHTR device has a shaft device that is designed to fit into the working channel of any hysteroscope that includes a 3.0 mm (Fr) straight working channel. Polygon™/PolyGone® consists of a hand-held trigger assembly consisting of a handle with a built-in mechanical gear drive, a manually rotating torsional wheel, a cutting assembly, and a suction system. The device is activated by squeezing the trigger as there are no electrical or powered connections necessary for operation. When the trigger is released, the elastic force is extended and transmitted to the cutting edge through a gear drive, achieving a single straight and vertical cutting of the tissue in an instant. A rotation knob enables the physician to rotate the cutting bay into an orientation that aligns with the desired specimen. The barb fitting provides an attachment port for a vacuum system, which pulls the specimen into the cutting window where it is resected and aspirated from the uterus.

4. Application of the Polygon/PolyGone Disposable mHTR Device in Both Operating Room or Office Setting

The collective experience and the effectiveness of this manual mHTR in both the operating room and office setting comes from 157 infertile women who underwent hysteroscopic polypectomy, 111 of which were performed in the operating room and 46 in the office. The mean age of patients was 32.9±5.5 years, monitored anesthesia care was administered for all operating room cases, while in the office setting, 10.8% required a paracervical block, and 89.2% had a vaginoscopic approach not requiring any anesthesia. All polyps were 2.0 cm or smaller. The procedural time of operating room cases was 27.1 ± 6.4 min, range 15–60 min compared to office setting cases which were only 7.3 ± 1.8 min, range 5–10. Complete resection rate was accomplished in 98.1% of cases with blood loss was <10 mL. Two cases in the operating room required graspers due to the cornual location of the pathology and a fibrous band that necessitated scissors for complete resection, while all specimens had adequate and benign histopathologic diagnosis except for one case with adenomatous hyperplasia. No intra- and post-operative complications were noted in either group. This confirms the ease of use and effectiveness of this manual mHTR device for hysteroscopic polypectomy in either the operative or office setting.

5. Steps Forward

As patient demand for less invasive approaches to address intrauterine pathology increases, simpler options may accelerate the adoption of manual mHTR procedures for intrauterine pathologies. Our preliminary findings present a new manual mHTR system for which the presented data demonstrate its effectiveness in the removal of intrauterine polyps. We recognize the limitations of our report, including the lack of a comparison group, which limits the generalizability of our results and different surgical approaches by the two surgical centers. We are currently gathering data on long-term issues, including pregnancy outcomes. Nonetheless, further studies are required to (1) establish their long-term efficacy, similar to electromechanical HTR systems for intrauterine polyps and/or myomas; (2) given the Polygon/PolyGone and other manual mHTR systems are not designed to remove submucosal myomas, clinical outcomes regarding their removal as well as retained products of conception are needed; and (3) cost-effectiveness studies are required to assess its full economic benefits.