DUETS (Dallas UtErus Transplant Study): The role of imaging in uterus transplantation

Imaging of Uterine Transplantation

Uterus transplantation (UTx) is a novel procedure being studied as a treatment of absolute uterine factor infertility. Imaging plays an important role throughout the life cycle of a uterus transplant. In this review, we will first describe the surgical technique of UTx. The article will then focus on the importance of imaging in the evaluation of potential recipients and donors and during the immediate post-surgical time course as graft viability is established. Imaging as part of including in vitro fertilization, pregnancy, and complications will also be discussed.

Graft Failure after Uterus Transplantation in 16 Recipients: A Review

Uterus transplantation (UTx) is now an alternative to surrogacy and adoption for women with uterine factor infertility to have children; however, there are still unresolved clinical and technical issues. One of these is that the graft failure rate after transplantation is somewhat higher than that of other life-saving organ transplants, which is a critical concern. Herein, we summarize the details of 16 graft failures after UTx with living or deceased donors using the published literature in order to learn from these negative outcomes. To date, the main causes of graft failure are vascular factors (arterial and/or venous thrombosis, atherosclerosis, and poor perfusion). Many recipients with thrombosis develop graft failure within one month of surgery. Therefore, it is necessary to devise a safe and stable surgical technique with higher success rates for further development in the UTx field.

Early Uterine Transplant Graft Loss Due to Thrombosis: Single-Center Experience With Causes, Prevention, Diagnosis, and Treatment

Uterus transplantation (UTx) is a promising treatment option for women who wish to give birth but suffer from absolute uterine factor infertility. This paper presents an interim analysis of a trial focusing on the causes, prevention, diagnosis, and management of graft thrombosis. Our team analyzed 10 cases of UTx (recipients numbered 1 to 10). Early thrombosis developed in 2 of 10 (20 %) recipients, and thrombectomy and temporary viability preservation were achieved in both cases. However, re-thrombosis developed in both cases, and a graft hysterectomy was carried out. In recipient number 2, vascular changes might have contributed to graft thrombosis. The histopathological finding of the explant revealed subintimal excentric fibrosis with focal sclerotic changes. In recipient number 8, thrombosis was facilitated by external compression of the vascular pedicles by the hematoma as well as production of de novo donor-specific antibodies. Thrombosis led to graft loss in both cases despite an attempt at a thrombectomy. Therefore, the focus must be on the prevention including a thorough evaluation of the donor candidate. In the postoperative course, perfusion is closely followed-up with an ultrasound, Doppler flow monitoring, and macroscopic evaluation of the cervix. In the case that findings are unclear, a relaparotomy should be promptly indicated. If thrombosis is revealed, a thrombectomy and an attempt to salvage of the graft are indicated; however, the role of this strategy is questionable due to the low chance of long-term success. The indication of upfront graft removal and early re-transplantation in the treatment of uterine graft remains debatable.

Early Uterine Transplant Graft Loss Due to Thrombosis: Single-Center Experience With Causes, Prevention, Diagnosis, and Treatment

Uterus transplantation (UTx) is a promising treatment option for women who wish to give birth but suffer from absolute uterine factor infertility. This paper presents an interim analysis of a trial focusing on the causes, prevention, diagnosis, and management of graft thrombosis. Our team analyzed 10 cases of UTx (recipients numbered 1 to 10). Early thrombosis developed in 2 of 10 (20 %) recipients, and thrombectomy and temporary viability preservation were achieved in both cases. However, re-thrombosis developed in both cases, and a graft hysterectomy was carried out. In recipient number 2, vascular changes might have contributed to graft thrombosis. The histopathological finding of the explant revealed subintimal excentric fibrosis with focal sclerotic changes. In recipient number 8, thrombosis was facilitated by external compression of the vascular pedicles by the hematoma as well as production of de novo donor-specific antibodies. Thrombosis led to graft loss in both cases despite an attempt at a thrombectomy. Therefore, the focus must be on prevention including a thorough evaluation of the donor candidate. In the postoperative course, perfusion is closely followed-up with an ultrasound, Doppler flow monitoring, and macroscopic evaluation of the cervix. In the event that findings are unclear, a relaparotomy should be promptly indicated. If thrombosis is revealed, a thrombectomy and an attempt to salvage the graft are indicated; however, the role of this strategy is questionable due to the low chance of long-term success. The indication of upfront graft removal and early re-transplantation in the treatment of uterine graft remains debatable.

Radiologic Evaluation of Uterine Vasculature of Uterus Transplant Living Donor Candidates: DUETS Classification

Uterus transplantation is a treatment solution for women suffering from absolute uterine factor infertility. As much as 19.5% of uterus-transplanted patients underwent urgent graft hysterectomy due to thrombosis/hypoperfusion. The necessity to identify candidates with high-quality uterine vasculature is paramount. We retrospectively evaluated and compared the imaging results with actual vascular findings from the back table. In this article, we present a novel radiologic grading scale (DUETS classification) for evaluating both uterine arteries and veins concerning their suitability for uterus procurement and transplantation. This classification defines several criteria for arteries (caliber, tapering, atherosclerosis, tortuosity, segment, take-off, and course) and veins (caliber, tapering, plethora, fenestrations, duplication/multiplicity, dominant route of venous drainage, radiologist’s confidence with imaging and assessment). In conclusion, magnetic resonance angiography can provide reliable information on uterine venous characteristics if performed consistently according to a well-established protocol and assessed by a dedicated radiologist. The caliber of uterine arteries seems to be inversely related to the time passed since the last delivery. We recommend that the radiologist comments on the reliability and confidence of the imaging study. It cannot be over-emphasized that the most crucial aspect of surgical imaging is the necessity of high-quality communication between a surgeon and a radiologist.

Technological Advancements in Uterus Transplantation

Uterus transplantation is barely a decade old and in a young, evolving field it is hard to identify "technological advances" since it is, in of itself, a technological advance. Nonetheless, one can still identify advances in diagnostic imaging that have improved donor screening to avoid graft losses, highlight the adoption of robotic surgery to make the living donor uterus procurement more minimally invasive, and look to a future of biotechnology like perfusion pumps and bioengineering such as synthetic uterus to increase donor supply. Additional technologies are on the horizon and promise to shape the field further.

Imaging evaluation of uterine arteries in potential living donors for uterus transplantation: a comparative study of MRA, CTA, and DSA

OBJECTIVE

To evaluate uterine arteries (UA) of potential living donors for uterus transplantation (UTx) by comparison of CT angiography (CTA), digital subtraction angiography (DSA), and MR angiography (MRA) with care taken to minimize radiation doses.

METHODS

Prospective donors for a clinical UTx trial were included. CTA, DSA, and MRA measurements in three predefined segments of the UAs were evaluated. Radiation doses were estimated and 1-year graft survival was recorded.

RESULTS

Twelve potential donors (age 37-62 years) were investigated. There was no difference in visualized average UA lumen diameter when comparing CTA (mean 2.0 mm, SD 0.4), DSA (mean 2.1 mm, SD 0.6), and MRA (mean 2.0 mm, SD 0.3). MRA was not able to fully evaluate 10 (43%) out of 23 UA that proved to be patent on DSA. One UA was not identified by any of the modalities, and three MRA-absent UAs were identified by both CTA and DSA. The estimated mean effective dose was lower for DSA (5.1 mSv, SD 2.8) than CTA (7.1 mSv, SD 2.0), but not significantly (p value = 0.06). Three potential donors were excluded due to UA pathology and one due to adenomyosis. Eight donors underwent hysterectomy, with 1-year graft survival in six women.

CONCLUSION

MRI including MRA should be the initial modality to examine potential UTx donors to acquire valuable details of uterine anatomy, and if UAs are fully visualized, there is no need for further angiographic methods with radiation. If UAs are not visualized by MRA, CTA may be performed and in selective cases with addition of the invasive modality DSA.

KEY POINTS

• For uterine transplantation, pelvic MRI with MRA provides information of the uterine structure and of the diameters of uterine arteries in living donors. • Failure of MRA to demonstrate uterine arteries could be followed by CTA which will visualize the uterine arteries in a majority of cases. If MRA and additional CTA provide inconclusive results, the uterine arteries should be further evaluated by DSA. • Information of CTA can be used in the angio-system for DSA settings to minimize the radiation and contrast media doses.

Human Uterus Transplantation from Living and Deceased Donors: The Interim Results of the First 10 Cases of the Czech Trial

Introduction: Uterus transplantation (UTx) is a rapidly evolving treatment of uterine-factor infertility. We report the results of the first 10 UTx procedures performed at our institution. Methods: The program started in April 2016 as a two-arm study comparing the efficacy of UTx from live donors (LD) and deceased donors (DD). Results: Between April 2016 and April 2018, we performed five DD UTx and five LD UTx. Two grafts had to be removed early due to thrombosis. One graft was removed due to chronic rejection and previous herpes simplex infection at month 7. Graft survival is 70% at one year. Recipient survival is 100% at two years. Live donor survival is 100% at three years. Three live-births have been achieved, two from a LD and one from a graft from a nulliparous DD. Vaginal anastomotic stenosis occurred in 63% (5/8) of grafts. Self-expanding stents have shown preliminary suitability for the treatment of vaginal stenosis. Three recipients developed severe acute rejection. Conclusion: The interim results of our study demonstrate mid-term viability in 70% of grafts. The LD UTx produced two live births and the DD UTx produced one live birth. Nulliparous donors should be considered for donation.

Human uterine vasculature with respect to uterus transplantation: A comprehensive review

Due to the novelty of uterus transplantation, data on preferable inflow and outflow of the graft are limited. This paper reviews the technique, type of vessels and the outcome. A systematic search of the PubMed database was conducted. We extracted and analyzed data on the arteries and veins utilized, types of anastomosis, types of donors, complications and the outcome. Thirty eight sources reported 51 human uterine transplantations, 10 graft thromboses and 25 live births. Inflow was established with two uterine arteries (UA) with/without the anterior division of the internal iliac artery in 62% (n = 31) of cases, two UA arteries with a segment/patch of the internal iliac artery in 34% (n = 17) of cases or two UA with a conduit in 4% of cases (n = 2). Both cases with a conduit developed thrombosis (n = 2). Arterial thrombosis/ischemia developed in 8 of the 51 cases. In 50% of cases with arterial thrombosis, atherosclerosis was identified as a possible cause. Outflow was established by two internal iliac veins with patches/segments in 27.5% of cases (n = 14) followed by two utero-ovarian veins in 25.5% (n = 13). Venous thrombosis occurred in 3 of the 51 cases. Uterine arteries with/without anterior division of the internal iliac artery were the most frequent arteries used for inflow and produced the highest patency rate. The presence of atherosclerosis and complex arterial reconstruction was associated with a high rate of arterial thrombosis. None of the veins utilized in the procedures appeared to be superior. There are insufficient data to draw a definite conclusion.

Uterus Transplantation with Live Donors: Screening Candidates in One French Center

We report our experience regarding the profile and screening process of potential recipients (R) and their live donors (D) in our Uterus transplantation (UTx) trial from 2014 to 2020. The initial screening was performed using medical questionnaires and consultations. The second step of the screening consisted of two individual interviews with an independent multidisciplinary committee. Then, a complete medical, biological and imaging assessment of the directed living D, the R, and her partner was performed over a two-day hospitalization. A total of 239 women contacted our department: 165 potentials R and 74 potentials D. During the first step of screening, 141 R and 45 D were excluded. Only 12 R/D pairs were pursued. During inclusion, 10 R/D pairs were excluded. One R/D pair is still under evaluation. Finally, only 1 R/D pair was definitively included (0.6%), which led us to perform the first French UTx in March 2019 with a successful graft. The primary limiting factors of inclusion were due to very strict criteria and difficulty of having a suitable directed living D. The International Society of UTx (ISUTx) guidelines based on worldwide results of trials can help ease our inclusion criteria in the future while remaining safe for patients.