Outcomes of embolization therapy of superior rectal arteries for the management of grade 1 to 3 internal hemorrhoids: a systematic Review of clinical studies

Abstract

Background

Superior rectal artery embolization (“Emborrhoid”) offers a catheter-based alternative for grade I–III internal hemorrhoids when office therapies fail or surgery is undesirable.

Methods

Following PRISMA 2020, PubMed and Embase were searched (Jan 2014–Jan 2024). Two reviewers independently screened records, extracted data, and applied RoB 2, ROBINS-I, or an adapted Newcastle–Ottawa Scale. Prespecified outcomes were technical success, clinical success (≥ 2-point fall in bleeding score or equivalent), adverse events, and recurrence. Substantial heterogeneity blocked meta-analysis; results were narratively synthesized.

Results

Twenty-two studies encompassing 810 procedures qualified. Technical success reached 93–100%. Clinical success ranged from 63 to 94%, yielding marked bleeding control and symptom relief. Reported complications were mild and self-limited (pelvic discomfort, nausea, and low-grade fever); no ischemic injury, continence disturbance, or mortality occurred. Recurrence necessitating repeat treatment affected 8–20% of patients, usually when collateral arterial supply persisted. Patient-reported satisfaction exceeded 80% in every series. Only two small, heterogeneous comparative studies versus rubber-band ligation or sclerotherapy were available, precluding a pooled analysis.

Conclusions

Current evidence suggests Emborrhoid is a safe, effective bridge between office procedures and surgery—particularly valuable for frail or anticoagulated patients. Yet small single-center cohorts, disparate techniques, and scarce head-to-head trials limit external validity. Multicenter randomized studies with harmonized outcomes and ≥ 24-month follow-up are required to confirm long-term efficacy, cost-effectiveness, and optimal patient selection.

Introduction

Hemorrhoids remain one of the most frequent gastrointestinal complaints, particularly among adults aged 45–65 [1, 2]; they appear in 39% of patients undergoing routine colorectal-cancer screening [3]. Once merely an anatomic term, “hemorrhoids” now refers to a pathologic enlargement of the normal anal cushions [3] with rectal bleeding as the hallmark symptom [4].

Internal and external hemorrhoids are distinguished by their position relative to the dentate line [4]. Internal disease is graded I–IV, and grades I–III are usually managed without surgery [1, 2]. Pathogenesis involves vascular dilation, connective-tissue degeneration, and dysregulated vascular tone—potential therapeutic targets [3].

Conservative measures help, yet office-based treatments—rubber-band ligation or sclerotherapy—are often needed [4]; ligation is favored for grades I–III because of lower failure rates [1] while surgery is effective but painful and carries risks of stricture or incontinence [3]. Clearly, a gap persists between simple office procedures and invasive surgery.

Embolization of the superior rectal arteries (“Emborrhoid”) has emerged to fill that gap [5], the technique occludes arterial inflow to the hemorrhoidal plexus [5, 6], preserves continence, and can be performed outpatient [5]. Reports describe no serious complications [5, 6] and technical success rates of 93–100% [5].

Yet evidence is scattered and prior reviews predate newer embolic materials and refined techniques, so an updated synthesis is warranted to clarify efficacy, safety, and recurrence and to position embolization alongside established non-surgical therapies.

Methods

This systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and the Cochrane Handbook of Systematic Reviews of Interventions.

Search strategy

A systematic search was conducted in PubMed/MEDLINE and Embase databases for studies published between January 2014 and January 2024. The search strategies included the following terms and Boolean operators:

PubMed/MEDLINE:

(“Superior Rectal Artery”[tiab] OR “Rectal Artery”[tiab]) AND (“Embolization, Therapeutic”[Mesh] OR “Embolisation”[tiab] OR “Emborrhoid”[tiab]) AND (“Hemorrhoids”[Mesh] OR “Haemorrhoid*”[tiab] OR “hemorrhoid*”[tiab]).

Embase:

Keywords included Emborrhoid and Embolization for hemorrhoid.

Study selection

Studies were eligible for inclusion if they (1) involved adult participants diagnosed with grade 1–3 internal hemorrhoids (excluding grade 4 hemorrhoids or populations requiring surgery-only interventions); (2) assessed embolization therapy as the primary intervention; (3) included comparators such as rubber band ligation, sclerotherapy, surgery, or pre- vs. post-embolization data; (4) reported at least one clinical or patient-related outcome (e.g., symptom relief, treatment success rate, recurrence rate, complications/adverse events, or quality-of-life improvements); and (5) were published as randomized controlled trials (RCTs), observational studies (cohort or case–control designs), or case series. Only English-language publications were included unless translations were unavailable.

Studies were excluded if they (1) lacked complete data or (2) combined grade 1–3 hemorrhoids with grade 4 cases without proper subgroup separation in outcomes or analysis.

Following duplicate removal, two independent reviewers screened titles and abstracts against predefined inclusion criteria. Full texts of potentially eligible studies were retrieved and evaluated for final eligibility. Discrepancies between reviewers were resolved through consensus or adjudication by a third reviewer. The screening process was documented in a PRISMA flow diagram, with explicit reasons for exclusion recorded at each stage (e.g., ineligible population, missing outcomes, and mixed grading).

Observational studies and case series were critically appraised for biases related to study design, confounding, and outcome reporting (Fig. 1).

Fig. 1.

PRISA flowchart

Data extraction and outcome measures

Two reviewers independently extracted study characteristics (design, country, sample size, hemorrhoid grade distribution, embolic material and catheter technique, comparator, and follow-up length) and all prespecified outcomes. When multiple articles described the same cohort, the most complete dataset was retained.

Risk of bias assessment

Two reviewers independently evaluated the methodological quality of each included study. For randomized controlled trials, they applied the Cochrane Risk of Bias 2 (RoB 2) tool, which examines randomization processes, deviations from intended interventions, missing outcome data, outcome-measurement methods, and selective reporting. For non-randomized comparative studies, they used the ROBINS-I framework to judge bias arising from confounding, participant selection, intervention classification, deviations from intended interventions, missing data, outcome measurement, and selective reporting. Single-arm cohorts and case series were appraised with an adapted Newcastle–Ottawa Scale that scores selection, comparability, and outcome assessment domains on a 0-to-9-star scale (scores ≥ 7 indicating high quality). Any disagreements between the reviewers were discussed and resolved by consensus.

Results

Included studies

For the review, a total of 22 studies were included, ranging from the years 2014–2024. Table 1 summarizes design, sample size, embolic agent, follow-up, and risk of bias for all included studies. Comparative effectiveness could not be assessed because almost all the papers included were single-arm case series without a control group; only two offered any comparator, and those comparators were different from each other. Outcome definitions (for example, what constituted “clinical success”), follow-up intervals (1 month to 3 years), and the embolic materials and techniques varied widely across studies. These design and reporting differences created such heterogeneity that pooling data—or even drawing a reliable qualitative ranking—would have been misleading. Accordingly, the “Results” section focuses solely on the outcomes of embolization itself.

Table 1.

Characteristics of clinical studies evaluating superior rectal artery embolization for grade I–III internal hemorrhoids

S. No	Author + year	Country	Study design	N	Embolization details	Primary outcomes	Follow-up (months)	RoB
1	Tutino R et al., 2024	Italy	Prospective	11	Coils + microspheres	changes in arterial hemorrhoidal flow	1	Serious (ROBINS-I)
2	Campennì, Paola et al., 2022	Italy	Prospective	21	Coils	Reduction in post defecation bleeding episodes	18.5 ± 6.0	Serious (ROBINS-I)
3	Iezzi R et al., 2021	Italy	Prospective	12	0.018-inch detachable coils	Complications: No procedure-related deaths or major morbidities	1	Serious (ROBINS-I)
4	Tradi, Farouk et al., 2018	France	Prospective	25	Microcoils	Clinical outcomes using the French bleeding score, Goligher prolapse score, visual analog scale (VAS) score for pain, quality-of-life score	12	Serious (ROBINS-I)
5	Moggia, Elisabetta et al., 2021	Italy	Prospective	16	Endovascular coils	Reduction of rectal bleeding with improvement of the quality of life	12	Serious (ROBINS-I)
6	A.Zakharchenko et al. 2016	France	Prospective	40	Metallic coils and synthetic polyvinyl alcohol particles	Clinical & physiologic assessment (rectoscopy, Doppler-flow, EMG/manometry) + patient satisfaction	0.03, 0.23, 1	Serious (ROBINS-I)
7	N Moussa et al. 2017	France	Prospective	30	Micro coils	Clinical outcome by evaluating bleeding and specific clinical scores relating to bleeding and changes in quality of life	5	Serious (ROBINS-I)
8	Giurazza et al. 2020	Italy	Prospective	5	Fibered coils	Safety and effectiveness in pts with portal hypertension and chronic anemia	3	Serious (ROBINS-I)
9	Puchol et al. 2019	Spain	Prospective	20	PVA particles and coils	Technical success, clinical success, and patient satisfaction	1	Serious (ROBINS-I)
10	De Gregorio et al. 2023	Spain	Prospective	240	Microcoils and microspheres	Bleeding, quality of life before, patient satisfaction	12	Serious (ROBINS-I)
11a	Nguyenhuy, Minhtuan et al., 2022	Australia	Systematic review and meta-analysis	NA	Rectal artery embolization	French bleeding score (FBS), visual analog scale (VAS) for pain, general quality of life (QoL) score, and the Goligher prolapse score (GPS)	NA	NA
12a	Sirakaya M et al., 2021	Multiple international centers	Review	NA	Coil vs. particle embolization	Clinical success: overall rate of 93%	NA	NA
13a	Talaie et al., 2022	USA	Review	NA	Microcoils, embolic particles	Efficacy, clinical outcomes, and morbidities	NA	NA
14a	Panneau et al. 2022	France	Review	NA	Fibered coils	Safety and effectiveness	NA	NA
15a	Buso Gil et al. 2022	Spain	Review	NA	Coils and particle	Clinical success rate	NA	NA
16a	De Nardi P et al., 2021	Multiple international centers	Editorial	NA	Microcoils, polyvinyl alcohol particles	Safety and effectiveness	NA	NA
17	Sun X et al., 2018	China	Retrospective	23	Coils	Ischemia, pain, symptom resolution	1, 6	Serious (ROBINS-I)
18	Han X et al., 2021	China	Retrospective	32	Gelatin sponge particles and metallic coils	Surgical efficacy, postoperative complications and follow-up outcomes	12	Serious (ROBINS-I)
19	Xuemin Wang et al. 2021	China	Retrospective	41	Coils + gelfoam particles Coils + microparticles	The technical success, preliminary clinical efficacy (percent hematochezia free), postoperative complications and short-term follow-up outcomes	12	Serious (ROBINS-I)
20	Küçükay MB et al., 2021	Turkey	Randomized control trial	42	Microspheres	Clinical success rate	12	Some concerns (Cochrane RoB 2)
21	V. Vidal et al. 2014	France	Case report	3	Coils	Feasibility and early morbidity	3	High (JBI)
22	Alves E Sousa et al., 2022	Portugal	Case report	1	Microcoils	Effectiveness, safety, reduction in bleeding	1.5	High (JBI)

^aSecondary evidence—excluded from quantitative synthesis

Origins of the emborrhoid technique

The articles identified for inclusion in this review were published between the years of 2014 and 2024, coming from various countries around the world. The technique of embolization of superior rectal arteries as a measure to treat hemorrhoids was first published in a case report by Vidal et al. in 2014, where they found that the method was technically feasible, safe, and efficacious in treatment [7]. Zakharchenko et al. in 2016 conducted a more in-depth study, where 40 patients underwent embolization of the superior rectal artery with metallic coils and polyvinyl alcohol particles. The study resulted in no observed ischemia or mucosal atrophy, and high levels of patient satisfaction, further giving weight to the potential of emborrhoid as a valid therapy for grade I–III hemorrhoids [8].

Attempts have been made at standardizing the technique by Panneau et al., who described their indications, procedure, and outcomes of the emborrhoid technique. Their studies revealed that the emborrhoid technique is preferred among patients for the high rates of success and despite the presence of minor side effects (nausea, vomiting, fever, pelvic pain, etc.) [9].

Indications for the technique

Moussa et al. (10)  found superior rectal artery embolization to be an effective solution in cases where surgery was contraindicated [10]. In 2018, Sun et al. found that the procedure was especially effective and necessary in cases where there were connections between arteries. While 54% of the participants had side effects, they were minor and the procedure still had high favorability among participants [11]. A retrospective study in China by Wang et al. in 2021 demonstrated the efficiency of the superior rectal artery embolization technique for treating bleeding hemorrhoids. The study compared different embolic particles (gelfoam versus microparticle) and had a technical success rate of 100% [12]. Küçükay et al. (2021) also studied the role of gelatin microspheres of a larger size (900–1200 µm) and found there was significant improvement of clinical symptoms, reduced bleeding, and no recurrence of disease [13].

A similar rate of technical success was achieved in Moussa et al. (14), and it was found that there was no statistically significant difference in outcomes when comparing procedures done with particles and coils, compared to only coils [14]. It is important to note that technical success differs from clinical success. The procedures were conducted successfully with no major complications or adverse effects, and 66% clinical success, where clinical success was defined as the participants having an improvement of greater than 2 points on the Paris bleeding score [14, 15].

Tradi et al. explored the possible utilization of the emborrhoid technique as a possible treatment for those cases in which medical treatment proved ineffective. The study found that 72% of patients had clinical success, although there were issues with recurrence of hemorrhoids among 8 out of the 18 patients who had success. The study indicated the need for proper patient selection, and the possibility of higher rates of clinical success among those without the presence of collateral supply to the hemorrhoids [16].

The technique was even found to be successful in cases with portal hypertension and among frail patients or those who had not responded well to more conservative approaches [17, 18]. It was first investigated among patients with portal hypertension by Giurazza et al., using the “spaghetti technique” of using fibered coils for the embolization. This study showed 80% of participants showing clinical improvement related to rectal bleeding, symptoms, and quality of life scores [19]. A similar technique using endovascular coils was performed by Moggia et al. in 2021, with an even higher clinical success rate of 87.5%, showing again reduced rectal bleeding and an improved quality of life [20]. Both studies had minimal side effects and complications among participants [19, 20].

More recently, Tutino et al. performed superior rectal artery embolization using microspheres among patients with grade II and III hemorrhoids. The outcomes showed a great degree of technical success (93–100%) and a satisfactory rate of clinical success (63–94%). The intervention resulted in decreased hemorrhoidal arterial flow [21].

Iezzi et al. conducted emborrhoid on patients considered to be a surgical risk and performed radial emborrhoid, with high rates of clinical success and improvement on follow-up [22].

Types of emborrhoid (materials, techniques, and advances)

The emborrhoid technique began with using endovascular coils to achieve embolization [7]. Advancements diversified as the procedure gained momentum, utilizing fibered coils, metallic coils, gelfoam, microparticles, polyvinyl alcohol particles, gelatin particles, or some combination of particles and coils [8, 9, 12, 21].

Drawbacks of the emborrhoid technique

Throughout the studies, there was high patient preference even in the presence of lower levels of clinical success. Studies showed instances of recurrence of hemorrhoids which required a second procedure due to a failure of the embolization [6, 9, 12, 16, 23]. This was especially seen in cases where there was collateral supply to the hemorrhoids [16].

Minor complications such as fever, nausea, pelvic pain, and vomiting were not uncommon [6, 9, 13, 16, 17]. No major complications were seen in any of the reviewed studies.

Discussion

In the case of hemorrhoids that are resistant to medical treatment or lifestyle interventions, office-based procedures are often the route to hemorrhoid management when the hemorrhoids are grades I–III. A few of the most commonly used office-based procedures in recent years are banding, injection sclerotherapy, radiofrequency ablation, and infrared photocoagulation [1, 4, 24]. Among these procedures, while rubber band ligation has low rates of recurrence and high safety, it is contraindicated in patients with bleeding disorders and those with concurrent anorectal sepsis [4]. While infrared photocoagulation has been found in some studies to have fewer side effects compared to rubber band ligation, it is hindered by its high cost of equipment [25]. Sclerotherapy, if improperly performed, can lead to a host of complications such as ulcerations, urinary symptoms, pain, and even impotence [26].

The emborrhoid technique presents as a viable and at times favorable alternative office-based treatment for grade I–III hemorrhoids.

Emborrhoid is an attractive option for atypical patients with grade I–III hemorrhoids, where other forms of office-based treatment or medications are contraindicated. It was found to be effective in patients where there were interconnections between arteries and among patients with chronic diseases such as portal hypertension [12, 17].

In the initial years of the emborrhoid technique’s implementation, the technique was associated with a higher rate of clinical failure, where there was insignificant improvement of bleeding or symptoms. The studies each experimented with using different materials and techniques for the embolization, starting with metallic coils and later extending to microgel spheres, particles composed of different substances, and a combination of coils and particles [8, 10, 12–14].

A factor that contributes to the potential of the emborrhoid technique is its safety. The explored studies had instances of complications such as pelvic pain, nausea, fever, and other minor complaints [9]. There were no major complications reported in any of the explored studies [6–14, 16, 17, 19–23]. The key feature of the emborrhoid’s success appears to be the reported improvement in patients’ quality of life across multiple studies [9, 10, 13, 17, 20].

Limitations

There remains much to be studied regarding the emborrhoid technique. Most studies used varying methods and materials for the technique, and therefore umbrella conclusions cannot be drawn about the technique as a whole. Although attempts were made at standardization, the existing studies are diverse in their approaches, methods, and materials [9]. This lack of standardization must be addressed in the future in order to validate the feasibility and success rate of the emborrhoid technique. Another drawback is the relatively smaller sample sizes of most studies. Vidal’s initial study of the emborrhoid technique constituted only three patients, and subsequent studies also had smaller sample sizes [7]. The studies were conducted primarily on European populations and within European countries, and the outcomes within such patient populations may not be replicated in patients of other races or regions. The universality of the technique needs exploring, and the actual strengths or performance of this method would benefit from being evaluated with comparative studies alongside other more established office-based procedures. Further work must be done on identifying the patients who are most suitable for the embolization of the superior rectal artery and will benefit most from it.

Recommendations for future research

Looking ahead, the next step for the field is a series of well-designed, multicenter randomized trials that compare embolization directly with standard office-based therapies such as rubber-band ligation, sclerotherapy, and, where appropriate, surgical hemorrhoidectomy. These studies should adopt harmonized definitions of technical success, clinical success, and recurrence, with at least two to three years of follow-up so that durability can be judged fairly across modalities. Just as important is the systematic collection of validated patient-reported outcomes, ensuring that procedural gains translate into meaningful improvements in quality of life. Subgroup analyses—by hemorrhoid grade, anticoagulation status, and prior treatment history—will help clarify which patients stand to benefit most from embolization. Finally, future work should explore technical refinements (optimal embolic material, particle size, and catheter approach), quantify operator learning curves, and incorporate robust cost-effectiveness evaluations across diverse health-care settings.

With its high degree of patient favorability and high safety, emborrhoid is a strong contender for treating grade I–III hemorrhoids not responsive to medical or conservative treatment and is a viable option for those in whom other office-based procedures and surgery may be contraindicated.

Conclusion

Superior rectal artery embolization (“Emborrhoid”) achieves a consistently high technical success rate (93–100%) and alleviates bleeding and other hemorrhoidal symptoms in a majority of treated patients (approximately 63–94%). Reported adverse events are almost uniformly minor—transient pelvic discomfort, nausea, or low-grade fever—and no major complications have been documented. Nonetheless, 10–20% of patients ultimately require repeat intervention owing to symptom recurrence.

These findings position embolization as a potential intermediary option between office-based therapies (rubber-band ligation, sclerotherapy) and surgical hemorrhoidectomy. It is especially attractive for individuals who are frail, anticoagulated, affected by portal hypertension, or otherwise unlikely to tolerate postoperative pain.

The strength of this evidence, however, is constrained by small sample sizes, single-center designs, and heterogeneity in embolic agents and procedural techniques. Head-to-head comparative trials, long-term durability data, and formal cost-effectiveness analyses are lacking. Until such rigorously conducted studies are available, superior rectal artery embolization should be regarded as an encouraging adjunct to existing treatment pathways rather than a definitive replacement for established modalities.

Author contribution

All authors contributed equally and attest they meet the ICMJE criteria for authorship and gave final approval for submission.

Data availability

No datasets were generated or analysed during the current study.

Declarations

Ethics approval

None.

Competing interests

The authors declare no competing interests.