MDCT and CT angiography evaluation of rectal bleeding: the role of volume visualization

Imaging and interventions in vascular malformations of the gastrointestinal tract

Vascular malformations of the gastrointestinal (GI) tract are a rare yet significant cause of GI bleeding, that can present at any age and require a high index of suspicion for timely diagnosis. While the majority of lesions may be asymptomatic and detected incidentally on imaging, they may also present with anemia if there is occult blood loss, as acute GI bleeding, or as lead points for intussusception. The presence of multiple vascular malformations may be associated with underlying syndromes, such as Hereditary Hemorrhagic Telangiectasia syndrome and Klippel-Trénaunay syndrome. While luminal endoscopy is the first-line diagnostic test to evaluate overt and occult GI bleeding, imaging plays a very significant role in detecting these vascular malformations and planning the best treatment approach. In this review, we describe the various imaging findings of GI tract vascular malformations and available treatment options, focusing on endovascular interventional treatments where possible.

Rectal Artery Embolization for the Treatment of Hemorrhoidal Disease

The term "hemorrhoid" is commonly invoked to characterize the pathologic process of symptomatic hemorrhoidal disease instead of the normal anatomic structure. While often treated with conservative measures, rectal artery embolization offers a minimally invasive alternative for patients with persistent or severe symptoms. This technique involves blocking the blood supply to the hemorrhoids using embolic agents, reducing blood flow, and alleviating symptoms. This review explores the clinical evaluation, techniques, and outcomes associated with rectal artery embolization for the treatment of hemorrhoidal disease. A discussion of the pathophysiology of hemorrhoids, the anatomy of rectal arteries, and the embolization procedure is provided in detail. Additionally, the safety and efficacy of the technique, including potential complications and outcomes, are reviewed.

Clinical management of active bleeding: what the emergency radiologist needs to know

Active bleeding is a clinical emergency that often requires swift action driven by efficient communication. Extravasation of intravenous (IV) contrast on computed tomography (CT) is a hallmark of active hemorrhage. This can be seen on exams performed for a variety of indications and can occur anywhere in the body. As both traumatic and non-traumatic etiologies of significant blood loss are clinical emergencies, exams demonstrating active bleeding are often performed in emergency departments and read by emergency radiologists. Prompt communication of these findings to the appropriate emergency medicine and surgical providers is crucial. Although many types of active hemorrhage can be managed by interventional radiology techniques, endoscopic and surgical management or clinical observation may be appropriate in certain cases. To facilitate optimal care, it is important for emergency radiologists to understand the scope of indications for embolization of bleeding by interventional radiologists (IR) and when an IR consultation is warranted. Similarly, timely comprehensive diagnostic radiology reporting including pertinent positive and negative findings tailored for IR colleagues can expedite the appropriate intervention.

The Utility of Submucosal Linear Enhancement on Dynamic Computed Tomography for Patients With Internal Hemorrhoids

OBJECTIVE

The purpose of this study was to evaluate the utility of submucosal linear enhancement on dynamic computed tomography (CT) for patients with internal hemorrhoids.

METHODS

We retrospectively reviewed patients who were admitted to our institution due to acute lower gastrointestinal bleeding and underwent both dynamic CT and colonoscopy. The presence of submucosal linear enhancement of the intestinal wall from the lower rectum to the anal canal was evaluated using arterial-phase CT images. Based on these images, patients were then classified into 2 groups by 2 blinded radiologists, as follows: group A (absence of submucosal linear enhancement) and group B (presence of submucosal linear enhancement). The relationship between the groups and the risk of bleeding in internal hemorrhoids was evaluated using the size and range of internal hemorrhoids measured during colonoscopy as reference standards.

RESULTS

A total of 94 patients were reviewed; of these, 62 patients without submucosal linear enhancement were classified into group A, and 32 patients with submucosal linear enhancement were classified into group B. Group B showed a significantly greater range (P = 0.017) and size (P = 0.002) of internal hemorrhoids. The Cohen κ coefficient value for the group classifications between the 2 radiologists was 0.66.

CONCLUSIONS

Submucosal linear enhancement on arterial-phase CT images could be a predictive finding suggesting the presence of internal hemorrhoids with a high risk of bleeding.

ECCO Topical Review on Clinicopathological Spectrum and Differential Diagnosis of Inflammatory Bowel Disease

INTRODUCTION

Many diseases can imitate inflammatory bowel disease [IBD] clinically and pathologically. This review outlines the differential diagnosis of IBD and discusses morphological pointers and ancillary techniques that assist with the distinction between IBD and its mimics.

METHODS

European Crohn's and Colitis Organisation [ECCO] Topical Reviews are the result of an expert consensus. For this review, ECCO announced an open call to its members and formed three working groups [WGs] to study clinical aspects, pathological considerations, and the value of ancillary techniques. All WGs performed a systematic literature search.

RESULTS

Each WG produced a draft text and drew up provisional Current Practice Position [CPP] statements that highlighted the most important conclusions. Discussions and a preliminary voting round took place, with subsequent revision of CPP statements and text and a further meeting to agree on final statements.

CONCLUSIONS

Clinicians and pathologists encounter a wide variety of mimics of IBD, including infection, drug-induced disease, vascular disorders, diverticular disease, diversion proctocolitis, radiation damage, and immune disorders. Reliable distinction requires a multidisciplinary approach.

Managing Recurrent Rectal Variceal Bleeding Secondary to Portal Hypertension With Liquid Embolics

Rectal variceal bleeding is one of the rarer manifestations of portal hypertension caused by chronic liver disease. The management of these varices is very challenging. Our patient had portal vein thrombosis and presented with chronic recurrent rectal bleeding requiring transfusion secondary to rectal varices. The patient was treated from trans-splenic access with liquid embolics (sclerotherapy and glue) without balloon occlusion, leading to the successful cessation of his bleeding. Access hemostasis was achieved using a vascular plug in the access tract. There are no clear guidelines for the management of these patients. If rectal varices cannot be managed by colonoscopy, this approach to embolization with liquid embolic is an excellent minimally invasive alternative.

CT of acute abdominopelvic hemorrhage: protocols, pearls, and pitfalls

Abdominal and pelvic hemorrhage may be secondary to a number of causes and is often a medical emergency. Patient presentation ranges from obvious trauma with evidence of hemodynamic instability to vague symptoms. CT has become the imaging modality of choice for identifying abdominopelvic hemorrhage. Recognizing acute hemorrhage as well as identifying its location and severity are key to expediting management. In the Emergency Department, ultrasound often used in the initial evaluation of trauma patients, but is not sensitive for subtle bleeds or injuries. CT is the best first-line imaging tool to identify abdominal hemorrhage and, compared with angiography, has been shown to be superior in detecting intra-abdominal bleeding, especially when the bleeding rate is low. Depending on location and etiology, abdominopelvic hemorrhage may have a characteristic appearance, such as the "sentinel clot" sign associated with blunt trauma to the solid organs or the "triangle sign" of a mesenteric bleed. The following pictorial essay reviews CT technique, study interpretation, and interpretative pearls and pitfalls in the recognition of acute abdominopelvic hemorrhage.

Contrast extravasation on computed tomography angiography in patients with hematochezia or melena: Predictive factors and associated outcomes

PURPOSE

The purpose of this study was to identify variables associated with extravasation on computed tomography angiography (CTA) in patients with hematochezia/melena and compare the outcome of patients with extravasation on CTA to those without extravasation.

MATERIAL AND METHODS

Ninety-four patients (51 men, 38 women; mean age, 69 ± 16 [SD] years) who underwent CTA within 30 days of hematochezia/melena were included. Variables associated with extravasation on CTA were searched using univariable and multivariable analyses. Outcomes of patients with visible extravasation on CTA were compared with those without visible extravasation.

RESULTS

One hundred and one CTA examinations were included. Extravasation was observed on 26/101 CTA examinations (26%). At multivariable analysis the need for vasopressor drugs (odds ratio [OR], 7.6; P = 0.040), high transfusion requirements (> 2 blood units) (OR, 7.1; P = 0.014), CTA performed on the day of a hemorrhagic event (OR, 46.2; P = 0.005) and repeat CTA (OR, 27.8; P = 0.011) were independently associated with extravasation on CTA. Extravasation on CTA was followed by a therapeutic procedure in 25/26 CTAs (96%; 26 patients) compared to 13/75 CTAs (17%; 68 patients) on which no extravasation was present (P < 0.001). No patients (0/26; 0%) with contrast extravasation on CTA died while 8 patients (8/61; 13%) without contrast extravasation died, although the difference was not significant (P = 0.099).

CONCLUSION

Extravasation on CTA in the setting of hematochezia or melena is especially seen in clinically unstable patients who receive more than two blood units. Presence of active extravasation on CTA leads to more frequent application of a therapeutic procedure; however, this does not significantly affect patient outcome.

Gastrointestinal Bleeding at CT Angiography and CT Enterography: Imaging Atlas and Glossary of Terms

Gastrointestinal (GI) bleeding is a common potentially life-threatening medical condition frequently requiring multidisciplinary collaboration to reach the proper diagnosis and guide management. GI bleeding can be overt (eg, visible hemorrhage such as hematemesis, hematochezia, or melena) or occult (eg, positive fecal occult blood test or iron deficiency anemia). Upper GI bleeding, which originates proximal to the ligament of Treitz, is more common than lower GI bleeding, which arises distal to the ligament of Treitz. Small bowel bleeding accounts for 5-10% of GI bleeding cases commonly manifesting as obscure GI bleeding, where the source remains unknown after complete GI tract endoscopic and imaging evaluation. CT can aid in identifying the location and cause of bleeding and is an important complementary tool to endoscopy, nuclear medicine, and angiography in evaluating patients with GI bleeding. For radiologists, interpreting CT scans in patients with GI bleeding can be challenging owing to the large number of images and the diverse potential causes of bleeding. The purpose of this pictorial review by the Society of Abdominal Radiology GI Bleeding Disease-Focused Panel is to provide a practical resource for radiologists interpreting GI bleeding CT studies that reviews the proper GI bleeding terminology, the most common causes of GI bleeding, key patient history and risk factors, the optimal CT imaging technique, and guidelines for case interpretation and illustrates many common causes of GI bleeding. A CT reporting template is included to help generate radiology reports that can add value to patient care. An invited commentary by Al Hawary is available online. Online supplemental material is available for this article. ^©RSNA, 2021.

Anorectal emergencies: WSES-AAST guidelines

Anorectal emergencies comprise a wide variety of diseases that share common symptoms, i.e., anorectal pain or bleeding and might require immediate management. While most of the underlying conditions do not need inpatient management, some of them could be life-threatening and need prompt recognition and treatment. It is well known that an incorrect diagnosis is frequent for anorectal diseases and that a delayed diagnosis is related to an impaired outcome. This paper aims to improve the knowledge and the awareness on this specific topic and to provide a useful tool for every physician dealing with anorectal emergencies.The present guidelines have been developed according to the GRADE methodology. To create these guidelines, a panel of experts was designed and charged by the boards of the World Society of Emergency Surgery (WSES) and American Association for the Surgery of Trauma (AAST) to perform a systematic review of the available literature and to provide evidence-based statements with immediate practical application. All the statements were presented and discussed during the WSES-AAST-WJES Consensus Conference on Anorectal Emergencies, and for each statement, a consensus among the WSES-AAST panel of experts was reached. We structured our work into seven main topics to cover the entire management of patients with anorectal emergencies and to provide an up-to-date, easy-to-use tool that can help physicians and surgeons during the decision-making process.

Vascular Malformation of the Colorectum in Children: Case Series of 27 Patients

BACKGROUND

Vascular malformation of the colorectum is a rare disease that presents most commonly in early childhood. Some pull-through procedures have been performed for its treatment. However, laparotomy was routinely required. The aim of this study was to present features of this disease, as well as the outcomes of transanal endorectal pull-through (TEPT) with or without laparotomy.

METHODS

A retrospective analysis was performed on consecutive patients with vascular malformation of the colorectum who underwent TEPT with or without laparotomy in our hospital between January 2010 and December 2019. Follow-up information included hematochezia, other bleeding and bowel function. Bowel function was assessed using the Rintala score.

RESULTS

Twenty-seven patients were included (14 boys and 13 girls). Hematochezia and anemia were the main chief complaints. Perianal vasodilatation and prolapse of rectal mucosa with spurting blood were detected in 13 (48.1%) and 9 (33.3%), respectively. Eighteen patients (66.7%) underwent TEPT with laparotomy, and 9 patients underwent TEPT without laparotomy (including 5 TEPT under laparoscopic supervision) for lesions located beyond the distal sigmoid colon. Compared to TEPT with laparotomy, the length of resected bowel and operative time was significantly shorter in TEPT without laparotomy (p = 0.001 and p = 0.004). There was no statistical difference for intraoperative blood loss. Other vascular malformations were detected in 9 patients (33.3%); 3 were detected by laparoscopy. Three patients (11.1%) experienced postoperative complications. Follow-up was held with 24 patients (3 were lost to follow-up). The mean follow-up time was 51.9 ± 32.8 months. Four patients occasionally had bloody stools, without anemia. None had hematuria or vaginal bleeding. Median bowel function score was 20 (range 17-20).

CONCLUSION

Hematochezia, anemia and hemorrhoid-like manifestations might be an indication for vascular malformation of the colorectum in children. TEPT was effective for vascular malformation of the colorectum, and TEPT without laparotomy was more suitable for the short lesions.

Multi-slice spiral CT evaluation of chronic radiation colitis and rectitis

The aim of the present study was to retrospectively analyse the multi-slice spiral CT (MSCT) findings of radiation colitis and rectitis (RC&R). A total of 23 cases of RC&R detected by helical CT were included. The CT findings and clinical and endoscopy data of the patients were reviewed. The primary tumours included cancers of the cervix (n=17), rectum (n=4), ovaries (n=1) and bladder (n=1). The total dose of radiation per patient was 46-60 Gy (mean, 49.7 Gy) delivered over 5 weeks. The CT manifestations included different degrees of increased thickness of the intestinal wall (n=20, 87.0%), with a maximum thickness of 16.6 mm. On enhanced CT, the target sign was observed (n=16, 69.9%), with an obviously enhanced mucosa and/or serosa and the following changes observed: Oedema and increased density of the mesentery (n=15, 65.2%); increased density of the subcutaneous fat, and blurred and oedematous pelvic wall muscles (n=4, 17.4%), with the obturator internus and levator ani muscles being most commonly affected; narrowed intestinal lumen (n=3, 13.0%); and a small amount of ascitic fluid (n=2, 8.7%) located in the paracolic sulci and bladder or Douglas pouch. The 23 patients underwent colonoscopy and were diagnosed with RC&R. The major manifestations included telangiectasia and mucosal hyperaemia (n=21, 91.3%). MSCT of chronic RC&R (CRC&R) was associated with certain characteristic findings, which, combined with a medical history of radiotherapy and the clinical manifestations, may prove to be of value in the diagnosis of CRC&R.

MRI of rectal cancer-relevant anatomy and staging key points

Rectal cancer has the eighth highest cancer incidence worldwide, and it is increasing in young individuals. However, in countries with a high human development index, mortality is decreasing, which may reflect better patient management, imaging being key. We rely on imaging to establish the great majority of clinical tumour features for therapeutic decision-making, namely tumour location, depth of invasion, lymph node involvement, circumferential resection margin status and extramural venous invasion. Despite major improvements in technique resulting in better image quality, and notwithstanding the dissemination of guidelines and examples of standardised reports, rectal cancer staging is still challenging on the day-to-day practice, and we believe there are three reasons. First, the normal posterior pelvic compartment anatomy and variants are not common knowledge to radiologists; second, not all rectal cancers fit in review paper models, namely the very early, the very low and the mucinous; and third, the key clinical tumour features may be tricky to analyse. In this review, we discuss the normal anatomy of the rectum and posterior compartment of the pelvis, systematise all rectal cancer staging key points and elaborate on the particularities of early, low and mucinous tumours. We also include our suggested reporting templates and a discussion of its comparison to the reporting templates provided by ESGAR and SAR.

Colopericardial fistula presenting with massive rectal bleeding

Colopericardial fistulae constitute a condition with a very low prevalence and a high morbidity and mortality rate. In this case report, we discuss an 80-year-old male patient who presented to emergency services for massive rectal bleeding and signs of hypovolemic shock. Abdominal arteriography and upper gastrointestinal endoscopy were negative for bleeding. Findings indicative of fistula between the left ventricle and the transverse colon were described in computed tomography angiogram and the diagnosis was confirmed endoscopically. The patient was stabilized and the bleeding was self-limited. Direct communication between the gastrointestinal tract and the pericardium, or even with the heart itself, is a rare disease and constitutes a diagnostic challenge.

Cinematic rendering of small bowel pathology: preliminary observations from this novel 3D CT visualization method

3D visualization methods for volumetric CT data have played an important role in diagnostic imaging of the small bowel, a structure which intrinsically crosses numerous slices in any 2D imaging plane. Recently, a new approach to 3D CT image creation has become available-cinematic rendering (CR). CR differs from other 3D methods in making use of a global lighting model that produces high surface detail and realistic shadowing effects that lead to 3D visualizations with photorealistic quality. Although the utility of these images for improving diagnostic accuracy has not yet been established, our group's early experience in regions of complex anatomy and pathology has been encouraging. In this pictorial review, we review the established role of 3D CT in many of the most common small bowel pathologies, provide examples of those pathologies visualized with CR, and suggest future directions for researchers to pursue.

Multimodality Imaging Review of Anorectal and Perirectal Diseases with Clinical, Histologic, Endoscopic, and Operative Correlation, Part II: Infectious, Inflammatory, Congenital, and Vascular Conditions

A broad spectrum of pathology affects the rectum, anus, and perineum, and multiple imaging modalities are complementary to physical examination for assessment and treatment planning. In this pictorial essay, correlative imaging, endoscopic, pathologic, and operative images are presented for a range of rectal, perirectal, and perineal disease processes, including infectious/inflammatory, traumatic, congenital/developmental, vascular, and miscellaneous conditions. Key anatomic and surgical concepts are discussed, including radiological information pertinent for surgical planning, and current operative approaches of these anatomic spaces to assist radiologists in comprehensive reporting for gastroenterologists and surgeons.

CT for Evaluation of Acute Gastrointestinal Bleeding

Acute gastrointestinal (GI) bleeding is common and necessitates rapid diagnosis and treatment. Bleeding can occur anywhere throughout the GI tract and may be caused by many types of disease. The variety of enteric diseases that cause bleeding and the tendency for bleeding to be intermittent may make it difficult to render a diagnosis. The workup of GI bleeding is frequently prolonged and expensive, with examinations commonly needing to be repeated. The use of computed tomography (CT) for evaluation of acute GI bleeding is gaining popularity because it can be used to rapidly diagnose active bleeding and nonbleeding bowel disease. The CT examinations used to evaluate acute GI bleeding include CT angiography and multiphase CT enterography. Understanding the clinical evaluation of acute GI bleeding, including the advantages and limitations of endoscopic evaluation, is necessary for the appropriate selection of patients who may benefit from CT. Multiphase CT enterography is used primarily to evaluate stable patients who have undergone upper and lower endoscopy without identification of a bleeding source. CT angiography is used to examine stable and unstable patients who respond to resuscitation, are believed to be actively bleeding, and are considered unlikely to have an upper GI source of hemorrhage. In the emergent setting, CT may yield critical information regarding the presence, location, and cause of active bleeding-data that can guide the choice of subsequent therapy. Recent developments in the use of and techniques for performing CT angiography have made it a potential first-line tool for evaluating acute GI bleeding. ^©RSNA, 2018.

Stercoral colitis complicated with ischemic colitis: a double-edge sword

BACKGROUND

Stercoral colitis is a rare inflammatory process involving the colonic wall secondary to fecal impaction with high morbidity and mortality; especially if complicated with ischemic colitis, stercoral ulcer formation and subsequent perforation. There are several case reports published on abdominal perforation resulting from stercoral colitis. However, stercoral colitis complicated by ischemic colitis is rare. The purpose of this case report is to describe the potential challenges in the diagnosis and management of stercoral colitis with ischemic colitis.

CASE PRESENTATION

An 87 years old male with history of chronic constipation presents with severe abdominal pain to the emergency department. The patient was hemodynamically stable. On physical examination, the abdomen was mildly distended with moderate tenderness. Lab work was significant for leukocytosis and lactic acidosis. Abdominal CT scan revealed large amount of retained stool in the colon, bowel wall thickening and infiltration of peri-colonic fat, which were suggestive for stercoral colitis. Patient was started on IV fluids and antibiotics. He was given an enema, followed by laxative and manual disimpaction of stool. Colonoscopy was performed and biopsies were obtained. Tissue biopsy was significant for focal active colitis with regenerative glandular changes and neural hyperplasia.

CONCLUSION

Elevated lactic acid level secondary to ischemia of the bowel wall with CT scan findings aid in establishing the diagnosis of stercoral colitis complicated with ischemic colitis. Urgent treatment with laxatives and fecal disimpaction is indicated to prevent perforation and peritonitis.

Gastrointestinal hemorrhage: evaluation with MDCT

Gastrointestinal (GI) bleeding is a common medical problem, with high associated morbidity and mortality. The clinical presentation of gastrointestinal hemorrhage varies with the location of the bleeding source, the intensity of the bleed, and the presence of comorbidities that affect the ability to tolerate blood loss. Conventional endoscopic examinations are usually the initial diagnostic tests in patients presenting with overt gastrointestinal hemorrhage. However, implementation of upper tract endoscopy and colonoscopy in the emergency setting can be challenging due to inconsistent availability of the service and difficulties in achieving adequate colonic cleansing in emergent situations. Thus, imaging tests are often relied upon to establish the location and the cause of bleeding, either for initial diagnosis or after non-revealing upper and lower tract endoscopies ("obscure" bleeding). This article discusses the imaging evaluation of patients with gastrointestinal bleeding and reviews the imaging appearance of the most common causes, taking into account the two most relevant clinical presentations: overt bleeding and obscure bleeding.

Evolution of imaging in rectal cancer: multimodality imaging with MDCT, MRI, and PET

Magnetic resonance imaging (MRI), multidetector computed tomography (MDCT), and positron emission tomography (PET) are complementary imaging modalities in the preoperative staging of patients with rectal cancer, and each offers their own individual strengths and weaknesses. MRI is the best available radiologic modality for the local staging of rectal cancers, and can play an important role in accurately distinguishing which patients should receive preoperative chemoradiation prior to total mesorectal excision. Alternatively, both MDCT and PET are considered primary modalities when performing preoperative distant staging, but are limited in their ability to locally stage rectal malignancies. This review details the role of each of these three modalities in rectal cancer staging, and how the three imaging modalities can be used in conjunction.