Extravasated contrast volumetric assessment on computed tomography angiography in gastrointestinal bleeding:A useful predictor of positive angiographic findings

BACKGROUND Gastrointestinal bleeding(GIB)is a severe and potentially life-threatening condition,especially in cases of delayed treatment.Computed tomography angiography(CTA)plays a pivotal role in the early identification of upper and lower GIB and in the prompt treatment of the haemorrhage.AIM To determine whether a volumetric estimation of the extravasated contrast at CTA in GIB may be a predictor of subsequent positive angiographic findings.METHODS In this retrospective single-centre study,35 patients(22 men;median age 69 years;range 16-92 years)admitted to our institution for active GIB detected at CTA and further submitted to catheter angiography between January 2018 and February 2022 were enrolled.Twenty-three(65.7%)patients underwent endoscopy before CTA.Bleeding volumetry was evaluated in both arterial and venous phases via a semi-automated dedicated software.Bleeding rate was obtained from volume change between the two phases and standardised for unit time.Patients were divided into two groups,according to the angiographic signs and their concordance with CTA.RESULTS Upper bleeding accounted for 42.9%and lower GIB for 57.1%.Mean haemoglobin value at the admission was 7.7 g/dL.A concordance between positive CTA and direct angiographic bleeding signs was found in 19(54.3%)cases.Despite no significant differences in terms of bleeding volume in the arterial phase(0.55 mL vs 0.33 mL,P=0.35),a statistically significant volume increase in the venous phase was identified in the group of patients with positive angiography(2.06 mL vs 0.9 mL,P=0.02).In the latter patient group,a significant increase in bleeding rate was also detected(2.18 mL/min vs 0.19 mL/min,P=0.02).CONCLUSION In GIB of any origin,extravasated contrast volumetric analysis at CTA could be a predictor of positive angiography and may help in avoiding further unnecessary procedures.

Deep learning model combined with computed tomography features to preoperatively predicting the risk stratification of gastrointestinal stromal tumors

BACKGROUND Gastrointestinal stromal tumors(GIST)are prevalent neoplasm originating from the gastrointestinal mesenchyme.Approximately 50%of GIST patients experience tumor recurrence within 5 years.Thus,there is a pressing need to accurately evaluate risk stratification preoperatively.AIM To assess the application of a deep learning model(DLM)combined with computed tomography features for predicting risk stratification of GISTs.METHODS Preoperative contrast-enhanced computed tomography(CECT)images of 551 GIST patients were retrospectively analyzed.All image features were independently analyzed by two radiologists.Quantitative parameters were statistically analyzed to identify significant predictors of high-risk malignancy.Patients were randomly assigned to the training(n=386)and validation cohorts(n=165).A DLM and a combined DLM were established for predicting the GIST risk stratification using convolutional neural network and subsequently evaluated in the validation cohort.RESULTS Among the analyzed CECT image features,tumor size,ulceration,and enlarged feeding vessels were identified as significant risk predictors(P<0.05).In DLM,the overall area under the receiver operating characteristic curve(AUROC)was 0.88,with the accuracy(ACC)and AUROCs for each stratification being 87%and 0.96 for low-risk,79%and 0.74 for intermediate-risk,and 84%and 0.90 for high-risk,respectively.The overall ACC and AUROC were 84%and 0.94 in the combined model.The ACC and AUROCs for each risk stratification were 92%and 0.97 for low-risk,87%and 0.83 for intermediate-risk,and 90%and 0.96 for high-risk,respectively.Differences in AUROCs for each risk stratification between the two models were significant(P<0.05).CONCLUSION A combined DLM with satisfactory performance for preoperatively predicting GIST stratifications was developed using routine computed tomography data,demonstrating superiority compared to DLM.

Usefulness of CT angiography in diagnosing acute gastrointestinal bleeding:A meta-analysis

AIM: To analyze the accuracy of computed tomography (CT) angiography in the diagnosis of acute gastrointestinal (GI) bleeding. METHODS: The MEDLINE, EMBASE, Cancerlit, Cochrane Library database, Sciencedirect, Springerlink and Scopus, from January 1995 to December 2009, were searched for studies evaluating the accuracy of CT angiography in diagnosing acute GI bleeding. Studies were included if the ycompared CT angiography to a reference standard of upper GI endoscopy, colonoscopy, angiography or surgery in the diagnosis of acute GI bleeding. Meta-analysis methods were used to pool sensitivity and specificity and to construct summary receiver-operating characteristic. RESULTS: A total of 9 studies with 198 patients were included in this meta-analysis. Data were used to form 2 × 2 tables. CT angiography showed pooled sensi-tivity of 89% (95% CI: 82%-94%) and specificity of 85% (95% CI: 74%-92%), without showing significant heterogeneity (χ2 = 12.5, P = 0.13) and (χ2 = 22.95, P = 0.003), respectively. Summary receiver operating characteristic analysis showed an area under the curve of 0.9297. CONCLUSION: CT angiography is an accurate, costeffective tool in the diagnosis of acute GI bleeding and can show the precise location of bleeding, thereby directing further management.

Interventional digital subtraction angiography for small bowel gastrointestinal stromal tumors with bleeding

AIM: To retrospectively evaluate the diagnostic efficacy of interventional digital subtraction angiography (DSA) for bleeding small bowel gastrointestinal stromal tumors (GISTs).

Factors influencing the yield of mesenteric angiography in lower gastrointestinal bleed

AIM: To assess if certain triaging rules could be established to optimize the yield of mesenteric angiography. METHODS: Medical records of 101 patients were retrospectively reviewed and parameters relating to age, gender, pulse rate, blood pressure, serum hemoglobin, intensive care unit(ICU) admission, and the number of packed red blood cells(PRBC) transfused in the 12 and 24 h prior to the angiography were tabulated in two groups with positive and negative angiography results. RESULTS: We found no correlation between gender, pulse rate, blood pressure or serum hemoglobin and positivity of the mesenteric angiogram. But patients with positive angiogram were found to be on average 7 years older(73.2 years vs 65.9 years old)(P = 0.02). Angiogram was positive in 39.3 %(11/28) of patientsadmitted in ICU vs 23.2%(17/73) who were admitted elsewhere in the hospital(P = 0.03). In the 12 and 24 h prior to angiography, patients with a positive angiogram received a mean of 2.7 ± 2.3 and 3.3 ± 2.6 units of PRBC s respectively, while patients with a negative angiogram had a mean of 1.6 ± 1.9(P = 0.02) and 2.1 ± 2.6 units(P = 0.04) received respectively in the same period. CONCLUSION: Older age, ICU admission, having received at least 4 units PRBC over 12 h or 5 units over 24 h prior to angiogram are leading indicators for a positive study.

Risk factors for rebleeding after angiographically negative acute gastrointestinal bleeding

AIM:To identify possible predictive factors for rebleeding after angiographically negative findings in patients with acute non-variceal gastrointestinal bleeding.METHODS: From January 2000 to July 2007, 128 patients with acute non-variceal gastrointestinal bleeding had negative f indings after initial angiography. Clinical and laboratory parameters were analyzed retrospectively.RESULTS: Among 128 patients, 62 had no recurrent gastrointestinal bleeding and 66 had recurrent gastrointestinal bleeding within 30 d. As determined by the use of multivariate analysis, an underlying malignancy, liver cirrhosis and hematemesis were significant factors related to recurrent gastrointestinal bleeding.CONCLUSION: Clinical factors including underlying malignancy, liver cirrhosis, and hematemesis are important predictors for rebleeding after angiographically negative findings in patients with acute non-variceal gastrointestinal bleeding.

Endoscopic hemostasis makes the difference:Angiographic treatment in patients with lower gastrointestinal bleeding

BACKGROUND The large majority of gastrointestinal bleedings subside on their own or after endoscopic treatment.However,a small number of these may pose a challenge in terms of therapy because the patients develop hemodynamic instability,and endoscopy does not achieve adequate hemostasis.Interventional radiology supplemented with catheter angiography(CA)and transarterial embolization have gained importance in recent times.AIM To evaluate clinical predictors for angiography in patients with lower gastrointestinal bleeding(LGIB).METHODS We compared two groups of patients in a retrospective analysis.One group had been treated for more than 10 years with CA for LGIB(n=41).The control group had undergone non-endoscopic or endoscopic treatment for two years and been registered in a bleeding registry(n=92).The differences between the two groups were analyzed using decision trees with the goal of defining clear rules for optimal treatment.RESULTS Patients in the CA group had a higher shock index,a higher Glasgow-Blatchford bleeding score(GBS),lower serum hemoglobin levels,and more rarely achieved hemostasis in primary endoscopy.These patients needed more transfusions,had longer hospital stays,and had to undergo subsequent surgery more frequently(P<0.001).CONCLUSION Endoscopic hemostasis proved to be the crucial difference between the two patient groups.Primary endoscopic hemostasis,along with GBS and the number of transfusions,would permit a stratification of risks.After prospective confirmation of the present findings,the use of decision trees would permit the identification of patients at risk for subsequent diagnosis and treatment based on interventional radiology.

Role of multidetector computed tomography angiography in nonvariceal upper gastrointestinal bleeding:A comprehensive review

Non-variceal upper gastrointestinal bleeding(NVUGIB)is a common gastroenterological emergency associated with significant morbidity and mortality.Upper gastrointestinal endoscopy is currently recommended as the gold standard modality for both diagnosis and treatment,with computed tomography traditionally playing a limited role in the diagnosis of acute NVUGIB.Following the introduction of multidetector computed tomography(MDCT),this modality is emerging as a promising tool in the diagnosis of NVUGIB.However,to date,evidence concerning the role of MDCT in the NVUGIB diagnosis is still lacking.The aim of our study was to review the current evidence concerning the role of MDCT in the diagnosis of acute NVUGIB.

Rare finding of primary aortoduodenal fistula on single-photon emission computed tomography/computed tomography of gastrointestinal bleeding: A case report

BACKGROUND Primary aortoduodenal fistula is a rare cause of gastrointestinal(GI)bleeding consisting of abnormal channels between the aorta and GI tract without previous vascular intervention that results in massive intraluminal hemorrhage.CASE SUMMARY A 67-year-old man was hospitalized for coffee ground vomiting,tarry stools,and colic abdominal pain.He was repeatedly admitted for active GI bleeding and hypovolemic shock.Intermittent and spontaneously stopped bleeders were undetectable on multiple GI endoscopy,angiography,computed tomography angiography(CTA),capsule endoscopy,and ^(99)mTc-labeled red blood cell(RBC)scans.The patient received supportive treatment and was discharged without signs of rebleeding.Thereafter,he was re-admitted for bleeder identification.Repeated CTA after a bleed revealed a small aortic aneurysm at the renal level contacting the fourth portion of the duodenum.A ^(99)mTc-labeled RBC singlephoton emission CT(SPECT)/CT scan performed during bleeding symptoms revealed active bleeding at the duodenal level.According to his clinical symptoms(intermittent massive GI bleeding with hypovolemic shock,dizziness,dark red stool,and bloody vomitus)and the abdominal CTA and ^(99)mTc-labeled RBC SPECT/CT results,we suspected a small aneurysm and an aortoduodenal fistula.Subsequent duodenal excision and duodenojejunal anastomosis were performed.A 7-mm saccular aneurysm arising from the anterior wall of the abdominal aorta near the left renal artery was identified.Percutaneous intravascular stenting of the abdominal aorta was performed and his symptoms improved.CONCLUSION Our findings suggest that ^(99)mTc-labeled RBC SPECT/CT scanning can aid the diagnosis of a rare cause of active GI bleeding.

0D-1D coupling model and 3D fluid-structure interaction model based on coronary CT angiography for displaying hemodynamic characteristics of coronary artery stenosis

Objective To observe value of 0D-1D coupling model and 3D fluid-structure interaction(FSI)model based on coronary CT angiography(CCTA)for displaying hemodynamic characteristics of coronary artery stenosis.Methods Based on CCTA data of the stenosed left anterior descending branch(LAD)in a patient with coronary heart disease,an 0D-1D coupling model and 3D FSI model were built,respectively.Then hemodynamic characteristic indexes,including the pressure,flow velocity and wall shear stress(WSS)were obtained in every 0.01 s during 1 s at 5 sampling points(i.e.sampling point 1—5)using these 2 models,respectively,and the consistencies of the results between models were evaluated with Spearman correlation coefficient r s.Results The time consuming for construction of 0D-1D coupling model and 3D FSI model was 0.033 min and 704 min,respectively.Both models showed basically distribution of the pressure,flow velocity and WSS of the stenosed LAD.For more details,the pressure at the stenosed segment of LAD and the proximal segment of stenosis were both higher,which gradually decreased at the distal segment of stenosis,and the flow velocity at the proximal segment of stenosis was in a relatively slow and uniform condition,with significantly increased flow velocity and WSS at the stenosed segment.Compared with 3D FSI model,0D-1D vascular coupling model was relatively unrefined and lack of distal flow lines when displaying blood flow velocity.For sampling point 2 at the stenosed segment of LAD,no significant consistency for pressure between 2 models was found(P=0.118),but strong consistency for the flow velocity and WSS(r s=0.730,0.807,both P<0.05).The consistencies of pressure,flow velocity and WSS between 2 models at the proximal and distal segment of stenosis,i.e.1,3—5 sampling points were week to moderate(r s=0.237—0.669,all P<0.05).Conclusion 0D-1D coupling model exhibited outstanding computational efficiency and might provide relatively reasonable results,while 3D FSI model showed higher accuracy for details and streamline when simulating LAD stenosis.

Active gastrointestinal diverticulum bleeding diagnosed by computed tomography angiography

A diverticulum is a bulging sack in any portion of the gastrointestinal tract. Small intestine diverticular disease is much less common than colonic diverticular disease. The most common symptoms include non-specific epigastric pain and a bloating sensation. Major complications include diverticulitis, gastrointestinal bleeding, acute perforation, intestinal obstruction, intestinal perforation, localized abscess, malabsorption, anemia,volvulus and bacterial overgrowth. We report one case of massive jejunal diverticula bleeding and one case of massive colonic diverticula bleeding, both diagnosed by acute abdominal computed tomography angiography and treated successfully by surgery.

Laparoscopic Small Bowel Resection of Gastrointestinal Stromal Tumour after Angiographic Diagnosis and Successful Embolization

Gastrointestinal stromal tumors (GIST) account for 2% of all tumors of the digestive tract. They are most frequently located in the stomach followed by the small intestine and most often present with mucosal ulceration and erosion associated with gastrointestinal bleeding. Bleeding from the small intestine can be difficult to diagnose and angiography becomes a useful diagnostic and therapeutic procedure in these patients. We present a case of a GIST located in the ileum which presented with a lower gastrointestinal bleeding (LGIB). The patient was stabilized by performing an arteriography and selective embolization of the bleeding point, followed by elective surgery.

Angiography findings and endovascular management of acute nonvariceal gastrointestinal bleeding:A pictorial essay

Patients with acute nonvariceal gastrointestinal bleeding(GIB)not treatable via endoscopic therapy require angiography and endovascular management.If the source of the bleeding can be identified on angiography,the bleeding can be controlled with minimal complications by endovascular treatments such as intra-arterial infusion of vasopressin,embolization,covered stent placement,or a combination thereof.This pictorial essay reviews the angiographic findings for and the endovascular management of acute nonvariceal GIB.

Recent advances in endovascular techniques for management of acute nonvariceal upper gastrointestinal bleeding

Over the past two decades,transcatheter arterial embolization has become the first-line therapy for the management of upper gastrointestinal bleeding that is refractory to endoscopic hemostasis.Advances in catheter-based techniques and newer embolic agents, as well as recognition of the effectiveness of minimally invasive treatment options,have expanded the role of interventional radiology in the management of hemorrhage for a variety of indications,such as peptic ulcerbleeding,malignant disease,hemorrhagic Dieulafoy lesions and iatrogenic or trauma bleeding.Transcatheter interventions include the following:selective embolization of the feeding artery,sandwich coil occlusion of the gastroduodenal artery,blind or empiric embolization of the supposed bleeding vessel based on endoscopic findings and coil pseudoaneurysm or aneurysm embolization by three-dimensional sac packing with preservation of the parent artery.Transcatheter embolization is a fast,safe and effective,minimally invasive alternative to surgery when endoscopic treatment fails to control bleeding from the upper gastrointestinal tract.This article reviews the various transcatheter endovascular techniques and devices that are used in a variety of clinical scenarios for the management of hemorrhagic gastrointestinal emergencies.

Role of interventional radiology in the management of acute gastrointestinal bleeding

Acute gastrointestinal bleeding(GIB) can lead to significant morbidity and mortality without appropriate treatment. There are numerous causes of acute GIB including but not limited to infection, vascular anomalies, inflammatory diseases, trauma, and malignancy. The diagnostic and therapeutic approach of GIB depends on its location, severity, and etiology. The role of interventional radiology becomes vital in patients whose GIB remains resistant to medical and endoscopic treatment. Radiology offers diagnostic imaging studies and endovascular therapeutic interventions that can be performed promptly and effectively with successful outcomes. Computed tomography angiography and nuclear scintigraphy can localize the source of bleeding and provide essential information for the interventional radiologist to guide therapeutic management with endovascular angiography and transcatheter embolization. This review article provides insight into the essential role of Interventional Radiology in the management of acute GIB.

Diagnosis of gastrointestinal bleeding: A practical guide for clinicians

Gastrointestinal bleeding is a common problem encountered in the emergency department and in the primary care setting. Acute or overt gastrointestinal bleeding is visible in the form of hematemesis, melena or hematochezia. Chronic or occult gastrointestinal bleeding is notapparent to the patient and usually presents as positive fecal occult blood or iron deficiency anemia. Obscure gastrointestinal bleeding is recurrent bleeding when the source remains unidentified after upper endoscopy and colonoscopic evaluation and is usually from the small intestine. Accurate clinical diagnosis is crucial and guides definitive investigations and interventions. This review summarizes the overall diagnostic approach to gastrointestinal bleeding and provides a practical guide for clinicians.

Interventional therapy for acute hemorrhage in gastrointestinal tract

AIM： To evaluate the diagnostic angiography and therapy for acute massive hemorrhage in gastrointestinal tract. METHODS： Twenty-five cases of acute hemorrhage in gastrointestinal tract admitted between April 2002 and September 2004 were reviewed and analyzed by angiography and embolotherapyo RESULTS： Fifteen patients were men and ten patients were women. The Seldinger technique and method of coaxial duct were used to get access to the bleeding region. PVA particles, gelfoam, and coils were used for embolism. All bleeding sites could be confirmed and were successfully embolized. Hemostasis was achieved in all the patients without bleeding again. The cure rate was 100%. CONCLUSION： Interventional therapy can not only ascertain the bleeding site, but also stop the bleeding .The method is simple and the effect is certain.

Analysis of negative DSA findings in patients with acute nonvariceal gastrointestinal bleeding: A retrospective study of 133 patients

Purpose: To analyze causes of acute nonvariceal gastrointestinal bleeding(GIB) with negative digital subtraction angiography(DSA) results.Materials and methods: The clinical and follow-up data of 133 patients-recruited between February 2008 and November 2016-with acute nonvariceal GIB and negative DSA results were included in this study. DSA results,diagnoses, and clinical outcomes were recorded.Results: The DSA results were negative in all 133 patients. Of the total, 55 patients(41.4%) chose to undergo surgery and 78(58.6%) opted for conservative treatment. Within 30 days, there was no significant difference in the rebleeding or mortality rates between the two groups(P <.05). Of all 133 patients, 76(57.1%) had upper GIB and 57(42.9%) had lower GIB;within 30 days, the rebleeding rate in the upper GIB group(44.7%, 34/76) was significantly higher than that in the lower GIB group(26.3%, 15/57). There was no significant statistical difference(P <.05) within 30 days in the mortality rates between the two groups.Among patients with upper GIB, 26(34.2%, 26/76) opted to undergo surgery and 50(65.8%, 50/76) chose conservative treatment;within 30 days, the rebleeding rate in the group that chose surgery(61.5%, 16/26) was higher than that in the conservative treatment group(36%, 18/50). There was no significant difference(P <.05)within 30 days in the mortality rate between the two groups.Among the patients with lower GIB, 29(50.9%, 29/57) chose to undergo surgery and 28(49.1%, 28/57) opted for conservative treatment. Within 30 days, the rebleeding rate in the surgery group(13.8%, 4/29) was lower than that in conservative treatment group(39.3%, 11/28). There was no significant difference(P <.05) within 30 days in the mortality rate between the two groups.Sixteen patients underwent prophylactic arterial embolization;in 6 of these, bleeding was stopped for 30 days.DSA was then repeated in these 16 patients after a median interval of 1 day, and a positive bleeding site was found in 9 of the 16. Causes of bleeding were found in 111 patients by surgery or endoscopy, whereas the causes remained unknown in 22 patients.Conclusions: Upper GIB with negative DSA results was stopped by conservative treatment, whereas lower GIB required surgery to detect the culprit bleeding site. Rare causes of GIB should be considered and appropriate management selected in a timely manner in order to detect unusual causes.

Significance of scintigraphy for the localisation of obscure gastrointestinal bleedings

AIM： To determine the role of scintigraphy in patients with gastrointestinal （GI） bleeding of unknown Iocalisation. METHODS： We performed retrospective analyses on 92 patients receiving scintigraphies from 1993 to 2000 in the University of Regensburg hospital, which were done for Iocalisation of GI bleeding as a diagnostic step after an unsuccessful endoscopy. In addition to the scintigraphies, further diagnostic steps such as endoscopy, angiography or operations were performed. In some of the scintigraphies with negative results, a provocation test for bleeding with heparinisation was carried out. RESULTS： 73% of all scintigraphies showed a positive result. In 4.5% of the positive results, the source was located in the stomach, in 37% the source was the small bowel, in 25% the source was the right colon, in 4.5% the source was the left colon, and in 20% no clear Iocalisation was possible. Only 4% of all scintigraphies were false positive. A reliable positive scintigraphy was independent of the age of the examined patient. A provocation test for bleeding with heparin resulted in an additional 46% of positive scintigraphies with a reliable Iocalisation in primary negative scintigraphies. CONCLUSION- Our results show that scintigraphy and scintigraphy with heparin provocation tests are reliable procedures. They enable a reliable Iocalisation in about half of the obscure GI-bleeding cases. Scintigraphy is superior to angiography in locating a bleeding. It is shown that even in the age of video capsule endoscopy and double-balloon enteroscopy, scintigraphy provides a reliable and directed localization of GI bleeding and offers carefully targeted guidance for other procedures.

Clinical value of CT three-dimensional imaging in diagnosing gastrointestinal tract diseases

AIM： To discuss the clinical value of CT three-dimensional （3-D） imaging in diagnosing gastrointestinal tract diseases.METHODS： Three-D imaging findings of 52 patients were retrospectively analyzed. Three-D imaging methods included shaded surface display （SSD）, volume rendering （VR）, virtual endoscopy （VE） and multiplanar reformatting （MPR）. The diagnosis results of CT 3-D were evaluated by comparison with those of endoscopy and/or surgical finding.RESULTS： Fifty-two patients with gastrointestinal tract diseases were diagnosed by CT 3-D imaging, of whom 50 cases were correctly diagnosed and 2 were misdiagnosed. There were 33 cases of gastric diseases （27 with carcinoma, 5 with peptic ulcer and 1 with leiomyoma） and 19 large intestinal diseases （10 with colon carcinoma, 2 with carcinoma of the rectum, 5 with colon polypus and 2 with tuberculosis of the ileocecal junction）. Twenty-two cases with prominent lesions （9 with subsequent hollow lesions）, 20 with stenosis of cavity （8 with concomitant prominent lesions） and 10 with hollow lesions （5 with concomitant prominent lesions） were shown in 3-D images. The minimal lesion shown was 1.0 cm × 0.8 cm × 0.5 cm.CONCLUSION： CT 3-D imaging, a non-invasive examination without pain, can display clearly and directly the lesions of gastrointestinal tract with accurate location and high diagnosis accuracy. It is an important complementary technique to endoscopy.