How to Treat Peripheral Arteriovenous Malformations

Treatment Effectiveness and Recurrence of Extracranial Arteriovenous Malformations Following Surgical Operations: A 15-Year Retrospective Cohort Study

BACKGROUND

At present, there is no golden standard for treatment of extracranial arteriovenous malformations (AVMs) and recurrence remains a major challenge with limited available evidence on the associated factors. This study aimed to evaluate the effectiveness of surgical treatment options, in terms of size reduction, symptoms, and early recurrence in patients treated surgically for AVMs.

METHODS

A retrospective cohort study was conducted to evaluate patients with AVMs following surgical treatment in 2 centers from 2005 to 2020. Posttreatment lesion size and symptoms, as well as recurrence, were assessed. Multiple regression analysis was performed to identify factors associated with recurrence.

RESULTS

Forty-four surgical treatment cases in 31 patients were assessed with a mean follow-up duration period of 67.9 ± 39.5 months. Treatment included total resection in 26 cases (59.1%) and partial resection 18 (40.9%), with free flap coverage used in 19 cases (43.2%). No acute exacerbation following treatment was observed in our cohort. Total resection significantly reduced posttreatment lesion size ( P < 0.001), symptoms ( P < 0.001), and recurrence (20.0%, P = 0.03). The recurrence rate was significantly higher after partial resection (73.7%, P = 0.03). Total resection was identified as an associated factor for significantly reduced AVM recurrence (odds ratio: 0.12; 95% confidence interval: 0.03, 0.52). However, the use of free flaps did not significantly reduce recurrence, post treatment size or improve AVM symptoms.

CONCLUSIONS

Total resection is the optimal treatment for AVMs. Free flaps are useful in covering large defects but the regulative effect of free flap remains controversial.

Ethanol embolization of arteriovenous malformations in the buttock: ten-year experiences in diagnoses and treatment options

BACKGROUND

Clinically, arteriovenous malformations in the buttocks (bAVMs) are extremely rare. Our study aimed to evaluate the efficacy and safety of ethanol embolotherapy in managing bAVMs.

RESULTS

A total of 32 patients with bAVMs (14 females and 18 males) from 2012 to 2021 were included in this study. All patients underwent complete clinical and imaging examinations. Further, the AVMs lesions were analyzed according to Schöbinger staging and Yakes classification. Each patient had undergone a multistage ethanol embolization. The amelioration of clinical symptoms and devascularization on angiography were evaluated at regular follow-ups. In the present cohort, the 11-20 age group had the most patients (15/32; 46.88%). A total of 124 embolization procedures were performed (average 3.88 procedures per patient), and the average dose of absolute ethanol was 18.96 mL per procedure. Thirteen patients with dominant draining veins underwent additional coil deployment before ethanol embolization (13/32; 40.63%). During follow-ups, clinical improvement was found in 23 of 27 who presented with a pulsating mass (85.19%), 17 of 20 with abnormal local skin temperature (85%), 5 of 6 with bleeding (83.33%), and 5 of 5 patients treated for pain (100%). More than 75% angiographic devascularization was achieved in 18 patients (18/32; 56.25%). Finally, 12 out of 13 patients (92.31%) reduced from Schöbinger Stage III to a lower grade, and ten patients exhibited a complete response (10/32; 31.23%). There was a single serious complication of local necrosis, while neither paranesthesia nor infection was observed postoperatively.

CONCLUSIONS

Ethanol embolization assisted with coils can treat bAVMs effectively and safely. The Yakes classification contributed to the optimal ethanol embolotherapy of bAVMs.

A rare case of Bannayan-Riley-Ruvalcaba syndrome with concurrent arteriovenous malformation

Bannayan-Riley-Ruvalcaba syndrome (BRRS) is a congenital, autosomal-dominant disorder characterized by a triad of macrocephaly, lipomatosis, and pigmentation of the glans penis. The symptoms of this rare syndrome vary greatly and include multiple hamartomatous polyps, macrocephaly, increased birth weight, developmental delay, and intellectual disability. Vascular abnormalities, including arteriovenous malformations (AVMs), have rarely been reported as part of the vascular manifestations associated with BRRS. Congenital AVMs can rarely progress, resulting in limb- or life-threatening complications. We present the case of a young man with BRRS diagnosed in childhood and presenting with three AVMs involving the right upper extremity and chest. We also provide a brief literature summary of reported cases of BRRS with AVMs. Our paper highlights the importance of recognizing and understanding the vascular manifestations in patients with BRRS. Knowledge of the association between BRRS and AVMs is crucial for guiding patient diagnosis and management, optimizing treatment strategies, and improving overall patient outcomes.

Combined DSA- and US-guided management of acute bleeding: effectiveness of percutaneous glue embolization in six cases

AIMS

This study aims to report on safety and effectiveness of glue embolization of acute hemorrhages performed by US-guided percutaneous direct puncture, in patients where the standard endovascular approach is technically unfavourable.

METHODS

In this single center retrospective analysis, patients affected by traumatic or non traumatic acute hemorrhages were treated with glue embolization technically performed by US-guided direct puncture. Patients suffered from active bleeding detected at contrast-enhanced Computer Tomography and confirmed at Digital Subtracted Arteriography, with concomitant hemoglobin drop and blood pressure reduction. Six patients were reviewed; hemorrhages occurred in liver parenchima (1), gallbladder (1) and lower limbs (4). Bleedings etiologies were post-traumatic (5) and inflammatory (1); four had extraluminal blushes while 2 were pseudoaneurysms. In five cases (4 limbs and 1 hepatic bleedings) the direct-puncture approach was adopted because of technically unfavourable vascular anatomy for superselective embolization; in one case (cystic artery pseudoaneurysm), an endovascular embolization would entail a high risk of gallbladder ischemia because of its terminal arterial supply. Technical success was defined disappearance of bleeding signs at last arteriography; clinical success was considered stabilization and/or improvement of hemoglobin values and arterial pressure without additional interventions.

RESULTS

Both technical and clinical successes were obtained in 100% of the cases without major complications. No needle occlusion occurred during glue injection.

CONCLUSIONS

In this study percutaneous US-guided embolization by direct puncture was a safe and effective approach to manage acute bleedings; it could be considered as an alternative in patients with unfavourable vascular anatomy for the standard catheter-directed endovascular embolization.

Calf arteriovenous malformation presenting as an iliac artery aneurysm: A case report

INTRODUCTION AND IMPORTANCE

Arteriovenous malformations (AVMs) are abnormal connections between arteries and veins. Common signs of AVMs include a pulsating mass, pain, ulceration, bleeding, and tissue necrosis. This case report discusses a rare presentation of an iliac artery aneurysm in a patient with an extensive calf AVM.

CASE PRESENTATION

A 35-year-old male presented with a pulsatile mass in the abdomen, along with symptoms of chronic venous insufficiency in the lower limb. He had undergone multiple surgeries for varicose veins in the past. Initially, external iliac artery aneurysm was diagnosed. Further assessment revealed the presence of an AVM in the calf. After multiple unsuccessful endovascular interventions, amputation was recommended. However, the patient opted for conservative management.

CLINICAL DISCUSSION

AVMs are vascular malformations that are present from birth. Angiography is considered the gold standard for confirming the diagnosis of AVMs. As there is no consensus on the best treatment for AVMs, a multidisciplinary approach is recommended on a case-by-case basis. Delaying treatment can lead to serious complications and increase morbidity and mortality. Treating extensive AVMs that involve the entire extremity can be particularly challenging and often result in poor outcomes.

CONCLUSION

The presence of varicose veins at a young age may indicate an underlying AVM. AVM can manifest in various ways, including arterial aneurysms. In severe cases, extensive AVMs may require limb amputation when other treatments fail.

Ethanol Embolotherapy for Cutaneous Erythema of High-Flow Vascular Malformations in the Head and Neck

BACKGROUND

Cutaneous erythema is one of the most common signs of arteriovenous malformations (AVMs) in the head and neck region, influencing aesthetic appearance. Surgical resection of AVMs may lead to cicatrization of the skin or aggravation of the lesion. Laser treatment, although effective in improving superficial vascular lesions, cannot prevent deep AVMs from further development.

OBJECTIVE

The authors propose an absolute ethanol embolization therapy that can effectively and safely eradicate the nidus with a favorable aesthetic outcome.

METHODS

The authors conducted a retrospective observational study of 14 AVM patients with distinct cutaneous erythema in the head and neck region undergoing embolotherapy in a single primary care center. Symptoms before and after treatment, complications, and degree of devascularization were recorded and assessed. Changes in cutaneous redness were evaluated using a previously reported quantitative measurement.

RESULTS

Complete symptomatic relief was observed in 5 patients, and major improvement was observed in 9 patients. The mean Δ a * value of the color change had a significant reduction of 6.50 ± 4.04, p < .001, indicating a remarkable remission of cutaneous erythema.

CONCLUSION

Ethanol embolization is an effective and safe treatment for head and neck AVMs with excellent aesthetic outcomes and might become a potential treatment method for other superficial vascular anomalies.

Coil-assisted ethanol embolotherapy for refractory head and neck arteriovenous malformations with Onyx recrudescence: 10-Year experiences

OBJECTIVE

This study aimed to evaluate the outcomes of coil-assisted ethanol embolotherapy in recanalized head and neck arteriovenous malformations (HNAVMs) with dilated outflowing veins after Onyx treatment.

METHODS

Thirty-six patients with HNAVMs (18 females and 18 males with a mean age of 26.83 years) who experienced recurrence after Onyx embolization from October 2007 to October 2017 were included in this study. All patients underwent complete clinical and angiographic examinations. Further, each patient was classified based on the Schobinger stage before undergoing staged ethanol embolization. All patients were followed up for 5 years in-person at an interval of 3 months after discharge. The Kaplan-Meier method was used to perform the recurrence-free survival analysis.

RESULTS

Sixteen patients (44.4%) had Schobinger stage II HNAVMs, and the remaining patients had Schobinger stage III or IV (20/36 patients [55.6%]) HNAVMs. A total of 116 embolization procedures were performed, coils were applied in 107 procedures (92.2%) among patients with dilated outflowing veins. The dose of absolute ethanol was 16.39 mL per procedure in patients with Schobinger II HNAVMs, and 22.45 mL per procedure in patients with Schobinger III and IV HNAVMs (P = .024, 95% confidence interval, 1.128-5.009). During the 3-month evaluation, complete response was observed in 13 of 36 patients (36.1%), and partial response was observed in 23 of 36 patients (63.9%). The 5-year recurrence-free survival rate for patients who underwent Onyx treatment had improved 58.3% after ethanol embolization (95% confidence interval, 2.853-9.595; P < .0001).

CONCLUSIONS

Coil-assisted ethanol embolotherapy could treat refractory HNAVMs with Onyx recrudescence effectively.

Overview of peripheral arteriovenous malformations: From diagnosis to treatment methods

Based on the latest classification by the International Society for the Study of Vascular Anomalies in 2018, vascular malformations (VMs) can be categorized into simple, combined VMs of major named vessels, and VMs associated with other anomalies. Simple VMs include lymphatic, venous, capillary, and arteriovenous malformations (AVMs). AVMs represent disorders of direct arteriovenous shunts caused by the absence of a capillary bed between the involved arteries and veins. This abnormal vascular communication causes arterial blood to accumulate in the venous vessels, thus resulting in venous hypertension and characteristic clinical manifestations, such as pulsation, tremors, and elevated temperature. AVMs can occur sporadically or as manifestations of syndromic lesions and are considered among the most complex and challenging VMs. The diagnosis and treatment of AVMs can vary depending on the lesion location and associated clinical symptoms, thus complicating their management. Herein, we discuss peripheral AVMs in terms of their clinical manifestations, imaging examinations, and staging systems to provide a comprehensive reference for the treatment, evaluation methods, and follow-up procedures for this vascular anomaly.

Angiographic Types of Palpebral Arteriovenous Malformations and Relevant Therapeutic Options Based on Ethanol Embolization: A Multicenter Study

PURPOSE

The present work aimed to determine the different angio-architectural types of palpebral arteriovenous malformations (pAVMs) and appropriate ethanol embolotherapy for each type.

MATERIALS AND METHODS

This was a multi-center comparative effectiveness research retrospectively conducted from November 2012 to October 2021. A total of 70 patients with pAVMs were included, which was classified into cystic pAVMs (n=29) and diffuse pAVMs (n=41) based on the angio-architecture. Of the included patients, 17 with cystic pAVMs and 13 with diffuse pAVMs underwent ethanol embolization combined with coils (CE). The remaining participants underwent no-coil ethanol embolization (NCE). Participants had undergone 60 months of follow-up. Normality of data was tested by the D'Agostino and Pearson test. Correlation was tested by the Pearson χ2 test. Deterioration-free survival (DFS) rate was estimated using the Kaplan-Meier survival analysis. Multivariate Cox regression models included variables that were significant at a p value<0.05 in the univariate analysis to screen the prognostic factor.

RESULTS

The local symptoms of pAVMs, including pulsation, warmth, red plaque, blepharoptosis, bleeding, and visual blurring, along with the devascularizational grade of angiography were recorded before and after the respective procedures. Post-treatment complications were either evaluated at the 3-month routine follow-up or were self-reported by patients. Cystic pAVMs presented with significantly different clinical and angiographic features compared with diffuse pAVMs. With CE, patients with cystic pAVMs obtained a higher devascularizational grade (p<0.0001) and better clinical outcomes (p=0.0009) than those with diffuse pAVMs. Contrarily, with NCE, patients with diffuse pAVM had better outcomes than those with cystic pAVMs (p=0.0248). Moreover, the overall DFS rate was higher in patients with cystic pAVMs (p=0.0006). Finally, the angio-architecture of pAVMs was found to independently influence its prognosis (p=0.02).

CONCLUSIONS

In pAVMs, the angio-architectural type was associated with the relative prognostic status. Ethanol embolization combined with coils was an effective method to treat cystic pAVMs, whereas NCE was more suitable for the diffuse type, further emphasizing the importance of a type-based therapeutic strategy for pAVMs.

CLINICAL IMPACT

Palpebral arteriovenous malformations (pAVMs) are rare and tricky in clinical practices. The present study has divided the pAVMs into cystic and diffuse types according to their angiographic characteristics. Ethanol embolization with (CE) or without coils (NCE) was performed on both types. CE was suitable for cystic pAVMs; whereas NCE was a better choice for diffuse pAVMs. The five-year survival analyses provided evidence of the safety and efficacy of ethanol application in pAVMs. Finally, our work demonstrated that both the short- and long-term clinical outcomes of diffuse pAVMs were poor compared to those of cystic pAVM.

Eradication of the nidus in arteriovenous malformations with a dominant outflow vein in the lower extremities using coils and absolute ethanol

OBJECTIVE

In the present study, we summarize our experience in locating the nidus of arteriovenous malformations (AVMs) with a dominant outflow vein (DOV) in the lower extremities and eradicating the nidus with ethanol and coils.

METHODS

Twelve patients with lower extremity AVMs who underwent ethanol embolization combined with DOV occlusion from January 2017 to May 2018 were enrolled in the present study. Selective angiography was used to locate the nidus of the AVMs, which was eradicated using ethanol and coils via the direct puncture pathway. All treated patients underwent postoperative follow-up (mean, 25.5 months; range, 14-37 months).

RESULTS

The 12 patients underwent a total of 29 procedures (mean, 2.4; range, 1-4) with 27 detachable coils and 169 Nester coils (Cook Medical Inc, Bloomington, IN). Of the 12 patients, 7 (58.3%) had a complete response and 5 (41.7%) a partial response. Three patients (25%) had minor complications such as blister and superficial skin ulcers during follow-up. However, they recovered spontaneously and completely. No major complications were recorded.

CONCLUSIONS

Ethanol embolization combined with coil-assisted DOV occlusion has the potential to eradicate the nidus of lower extremity AVMs with acceptable complication rates.

Embolo/sclerotherapy for the treatment of hand arteriovenous malformations: a single-center retrospective cohort experience

Purpose

To retrospectively report our preliminary experience of treating hand arteriovenous malformations (AVMs) with embolo/sclerotherapy.

Materials and methods

Retrospectively review the demographics, treatment detail, outcome data, and complications of 13 consecutive patients with hand AVMs from January 2018 to December 2021. We embolize the dominant outflow vein with elastic coils and then use absolute ethanol or polidocanol for intravascular sclerotherapy and bleomycin for interstitial sclerotherapy.

Results

Yakes type II presents in four lesions, type IIIa in six, and type IIIb in three. A total of 29 treatment episodes were conducted for the 13 patients (1 episode for 3 patients, 2 for 4 patients, and 3 for 6 patients; the repeated treatment rate was 76.9%). The mean stretched length of coils for 1 treatment episode was 95 cm. The mean absolute ethanol dosage was 6.8 ml (range 4-30 ml). In addition, 10 ml of 3% polidocanol foam was injected and interstitial sclerotherapy with 150,000 IU bleomycin was performed on every patient. The post-operative arterial-dominant outflow vein pressure index (AVI) increased in the 29 procedures (6.55 ± 1.68 vs. 9.38 ± 2.80, P < 0.05). The Mann-Whitney U test showed that the post-operative AVI was higher in patients without re-intervention (P < 0.05). Local swelling occurred after all the procedures. Blistering occurred in 6 of the patients in 13 (44.8%) of the 29 procedures. Superficial skin necrosis occurred in 3 of the patients in 5 (17.2%) of the 29 procedures. The swelling, blistering, and superficial skin necrosis recovered within 4 weeks. No finger amputation occurred. The follow-up time was 6 months. The 6-month assessment of clinical improvement after the last treatment episode showed that 2 patients were cured, 10 were improved, and 1 remained unchanged. With regard to angiographic evaluation, 9 showed partial response and 4 complete response.

Conclusion

Embolo/sclerotherapy can be effective and safe for hand AVM. The AVI increased significantly after embolo/sclerotherapy, and the index may be valuable in predicting recurrence in further study.

High-flow arteriovenous malformation in the finger with transvenous ethanolamine oleate sclerotherapy using an arterial tourniquet and microballoon occlusion: A case report

Endovascular therapy is an important method of treating high-flow arteriovenous malformations (AVMs). The nidus of AVMs can be treated by transarterial or percutaneous approaches with the use of ethanol as a strong embolic agent; however, treatment outcomes are not always satisfactory and complications including skin necrosis often occur, particularly following the treatment of superficial lesions. Herein, we describe successful transvenous sclerotherapy of high-flow AVMs in the finger of a 47-year-old female patient that were causing erythema and spontaneous pain using ethanolamine oleate (EO) as a safe sclerosant. Dynamic contrast-enhanced computed tomography and angiography revealed a high-flow type Ⅲb AVM according to Yakes classification. Using the transvenous approach, 5% EO with idoxanol was injected into the nidus of the AVM 3 times over 2 sessions. An arterial tourniquet was used to achieve stasis of blood flow at the nidus and microballoon occlusion of the outflow vein was used to ensure the sclerosant effectively reached the nidus. Near-total occlusion of the nidus was achieved leading to improved symptoms. Mild edema lasting 2 weeks occurred as a minor reaction after each session. Finger amputation may have been avoided by using this treatment. Transvenous EO sclerotherapy using an arterial tourniquet and balloon occlusion may have utility in treating AVMs in the extremities.

Inferior mesenteric artery arteriovenous malformation, a rare cause of ischemic colitis: A case report

RATIONALE

An arteriovenous malformation (AVM) is an abnormal tangle of blood vessels that connects the arteries and the veins. Because normal capillary bed is partially or completely absented in the AVM, the blood passes quickly from the arteries to the veins, which disrupts normal blood flow and oxygen supply to the surrounding tissues. This is called "steal phenomenon," and in the inferior mesenteric artery (IMA) territory, this may lead to abdominal pain, gastrointestinal bleeding, portal hypertension, and even ischemic colitis.

PATIENT CONCERNS

A 67-year-old man presented to our emergency department because of left side abdominal pain.

DIAGNOSES

The abdominal computed tomography with contrast enhancement revealed a cluster of abnormal vascular lesions abutting the IMA with early opacification of the left colonic marginal vein. In addition, poor enhancement of segmental colonic wall was found from proximal descending colon to middle rectum. The diagnosis of AVM of the IMA and ischemic colitis was made.

INTERVENTIONS

The patient underwent left hemicolectomy as well as the AVM resection.

OUTCOMES

He was discharged uneventfully after the surgery without complications.

LESSONS

IMA AVM carries the risk of ischemic colitis. computed tomography scan is helpful not only to the diagnosis of AVMs but also to exclude other lesions as well. Treatment options include endovascular embolization, surgical intervention, and a combination of both. Due to the complexity of this disease, treatment requires a case-specific multidisciplinary approach and a coordination of medical, radiological, and surgical staffs.

Early follow-up quality of life and mental health of patients with congenital vascular malformations cared for in a multi-disciplinary specialist centre

OBJECTIVE

The study aimed to evaluate the early follow-up quality of life (QoL), pain and mental health of patients with congenital vascular malformation (CVM) from a variety of treatment options.

METHODS

All patients with CVM who received care and had follow-up between February 1st 2018 and January 31st 2020 were included. The health-related QoL, pain, and mental health were assessed with RAND Health Care 36-Item Short Form Survey (SF-36), visual analogue score for pain (VAS-P) and Hospital Anxiety and Depression Scale (HADS). Paired t-test was used for all analyses. p < .05 were considered significant.

RESULTS

In total, 110 patients with a mean age of 36.9 years were included in this study. In all patients following care, significant improvement was found in the bodily pain domain of SF-36 and VAS-P (both p = .01). This was largely driven by high-flow vascular malformation patients who responded better to embolo-sclerotherapy, which revealed significant improvement in the bodily pain domain of SF-36 (p = .002) and VAS-P (p = .02). Patients who received supportive treatment only reported significant improvement in mental health (p = .004) and social functioning (p = .03) domains of SF-36. Meanwhile, patients treated with embolo-sclerotherapy reported significant improvement only in VAS-P (p = .02).

CONCLUSIONS

This study concluded that the effects of care on early follow-up QoL, pain and mental health of patients with CVM were heterogenous. Future research should therefore, include larger sample size and longer term follow-up to understand the various factors that affect the QoL and mental health of these patients, as well as the holistic approaches to manage them.

Shoulder Pain Associated With Multiple Arteriovenous Malformations Successfully Treated With Embolization

A 44-year-old male presented with left upper extremity and shoulder pain with worsening functional impairment after years of repetitive use, overtraining, and multiple injuries from weightlifting and mixed martial arts. Imaging showed no obvious injury or ligamentous deformity other than mild osteoarthritis (OA) of the left glenohumeral joint. Duplex ultrasonography (US) revealed four arteriovenous malformations (AVMs) surrounding the shoulder joint and left upper extremity. The vasculature was mapped via angiography through a transradial approach. Initial treatment included transarterial embolization of two AVMs off the axillary artery and branching anterior circumflex humeral artery. Secondary treatment included embolization of two lesions months later via direct puncture, one through a transvenous approach and the second through direct transmalformation cannulation, via the nidus, near the clavicle and posterior scapular lateral border. Treatment resulted in significant improvement in pain and range of motion. Follow-up assessments revealed improvement in overall symptoms, recovered function, and return to exercise and competitive mixed martial arts. This case highlights the value of duplex ultrasonography, embolization, and transarterial and transvenous approaches for the treatment of AVM-associated extremity or joint pain.

Case Report: A Rare Abdominopelvic Arteriovenous Malformation: Originating From Splenic Artery and Draining Into Portal Vein

Background

Abdominopelvic arteriovenous malformation is an uncommon congenital vascular lesion, for which the diagnosis and treatment are usually difficult. Though embolization and sclerotherapy are the primary treatment strategies, traditional surgical resection remains a valuable option.

Case Presentation

Herein, we present a 32-year-old female diagnosed with a massive abdominopelvic arteriovenous malformation that originates from the splenic artery and drains into the portal vein. The vascular lesion was evaluated with multiple imaging modalities and then surgically resected successfully. The patient was discharged post-operatively on day 6 and free of symptoms during the 12-month follow-up.

Conclusion

To our knowledge, the presented abdominopelvic arteriovenous malformation is the first to be reported in the literature, with such a rare condition originating from the splenic artery and draining into the portal vein.

Surgical management of auricular arteriovenous malformations: A literature review

Auricular arteriovenous malformations (AVMs) can cause a variety of symptoms that seriously impact the patient's appearance, life, and mental well‐being. Surgery is the primary management method for auricular AVMs, but there is no consensus on how to surgically manage auricular AVMs. In this article, we document a comprehensive review of the characteristics, classification, and surgical interventions to treat auricular AVMs.

Deep learning image reconstruction for pancreatic low-dose computed tomography: comparison with hybrid iterative reconstruction

PURPOSE

To evaluate image quality, image noise, and conspicuity of pancreatic ductal adenocarcinoma (PDAC) in pancreatic low-dose computed tomography (LDCT) reconstructed using deep learning image reconstruction (DLIR) and compare with those of images reconstructed using hybrid iterative reconstruction (IR).

METHODS

Our institutional review board approved this prospective study. Written informed consent was obtained from all patients. Twenty-eight consecutive patients with PDAC undergoing chemotherapy (14 men and 14 women; mean age, 68.4 years) underwent pancreatic LDCT for therapy evaluation. The LDCT images were reconstructed using 40% adaptive statistical iterative reconstruction-Veo (hybrid-IR) and DLIR at medium and high levels (DLIR-M and DLIR-H). The image noise, diagnostic acceptability, and conspicuity of PDAC were qualitatively assessed using a 5-point scale. CT numbers of the abdominal aorta, portal vein, pancreas, PDAC, background noise, signal-to-noise ratio (SNR) of the anatomical structures, and tumor-to-pancreas contrast-to-noise ratio (CNR) were calculated. Qualitative and quantitative parameters were compared between the hybrid-IR, DLIR-M, and DLIR-H images.

RESULTS

CT dose-index volumes and dose-length product in pancreatic LDCT were 2.3 ± 1.0 mGy and 74.9 ± 37.0 mGy•cm, respectively. The image noise, diagnostic acceptability, and conspicuity of PDAC were significantly better in DLIR-H than those in hybrid-IR and DLIR-M (all P < 0.001). The background noise was significantly lower in the DLIR-H images (P < 0.001) and resulted in improved SNRs (P < 0.001) and CNR (P < 0.001) compared with those in the hybrid-IR and DLIR-M images.

CONCLUSION

DLIR significantly reduced image noise and improved image quality in pancreatic LDCT images compared with hybrid-IR.