Gastrointestinal tract perforation: CT diagnosis of presence, site, and cause

Imaging of abdominopelvic oncologic emergencies

With advancements in cancer treatment, the survival rates for many malignancies have increased. However, both the primary tumors and the treatments themselves can give rise to various complications. Acute symptoms in oncology patients require prompt attention. Abdominopelvic oncologic emergencies can be classified into four distinct categories: vascular, bowel, hepatopancreatobiliary, and bone-related complications. Radiologists need to be familiar with these complications to ensure timely diagnosis, which ultimately enhances patient outcomes.

Evaluation of Abdominal Emergencies

Early primary assessment and abdominal examination can often be enough to triage the patient with abdominal pain into those with less severe underlying pathologic condition from those with more acute findings. A focused history of the patient can then allow the clinician to develop their differential diagnosis. Once the differential diagnoses are determined, diagnostic imaging and laboratory findings can help confirm the diagnosis and allow for expeditious treatment and intervention.

Deep Learning for Medical Image-Based Cancer Diagnosis

(1) Background: The application of deep learning technology to realize cancer diagnosis based on medical images is one of the research hotspots in the field of artificial intelligence and computer vision. Due to the rapid development of deep learning methods, cancer diagnosis requires very high accuracy and timeliness as well as the inherent particularity and complexity of medical imaging. A comprehensive review of relevant studies is necessary to help readers better understand the current research status and ideas. (2) Methods: Five radiological images, including X-ray, ultrasound (US), computed tomography (CT), magnetic resonance imaging (MRI), positron emission computed tomography (PET), and histopathological images, are reviewed in this paper. The basic architecture of deep learning and classical pretrained models are comprehensively reviewed. In particular, advanced neural networks emerging in recent years, including transfer learning, ensemble learning (EL), graph neural network, and vision transformer (ViT), are introduced. Five overfitting prevention methods are summarized: batch normalization, dropout, weight initialization, and data augmentation. The application of deep learning technology in medical image-based cancer analysis is sorted out. (3) Results: Deep learning has achieved great success in medical image-based cancer diagnosis, showing good results in image classification, image reconstruction, image detection, image segmentation, image registration, and image synthesis. However, the lack of high-quality labeled datasets limits the role of deep learning and faces challenges in rare cancer diagnosis, multi-modal image fusion, model explainability, and generalization. (4) Conclusions: There is a need for more public standard databases for cancer. The pre-training model based on deep neural networks has the potential to be improved, and special attention should be paid to the research of multimodal data fusion and supervised paradigm. Technologies such as ViT, ensemble learning, and few-shot learning will bring surprises to cancer diagnosis based on medical images.

Development and validation of a CT algorithm for the identification of nonperforated duodenal bulb ulcer

PURPOSE

To assess the value of multiplanar computed tomography (CT) in the diagnosis of nonperforated duodenal bulb ulcer (NPDBU).

METHOD

We retrospectively analyzed data from 135 patients with NPDBU (ulcer group) and 150 patients with a normal duodenal bulb (control group) who underwent contrast-enhanced abdominal CT and were diagnosed via upper endoscopy from January 2018 to February 2022. The clinical and CT features were compared between the two groups. Independent prognostic factors for diagnosing NPDBU were determined using binary logistic regression analysis. An external validation cohort to determine the model's efficiency comprised 80 patients from another center.

RESULTS

Gastrointestinal bleeding was more frequent in patients with NPDBU than in those without (p < 0.001). No significant differences in age and sex were observed between the groups (all p > 0.05). The duodenal bulbar wall was significantly thicker in the ulcer group than in the control group, as determined using CT (p < 0.001). Irregular mucosal surface, layered enhancement, and blurred fat space around the duodenal bulb were more common in the ulcer group than in the control group (all p < 0.001). Binary logistic regression analysis revealed that gastrointestinal bleeding, wall thickness of ≥ 4.85 mm, irregular mucosal surface, and blurred peripheral fat space were the most significant variations associated with NPDBU, with an area under the curve (AUC) of 0.974. The external validation cohort had an AUC of 0.916.

CONCLUSIONS

Careful multiplanar CT interpretation suggests the underlying presence of NPDBU and allows timely endoscopic verification and appropriate treatment.

Gastric rupture following multiple blunt trauma

Gastric injury due to trauma is a rare complication that occurs in approximately 0.04%-1.2% of all instances of abdominal trauma. When imaging trauma cases, certain areas can be obscured by several inevitable reasons. Despite its rarity, the high mortality rate of a gastric injury requires an early and accurate diagnosis. We present the case of an 18-year-old male who suffered a gastric rupture of the greater curvature following a road traffic collision before providing a brief review of the literature.

MDCT Findings in Gastrointestinal Perforations and the Predictive Value according to the Site of Perforation

Background: Gastrointestinal perforations are a frequent cause of acute abdominal symptomatology for patients in the emergency department. The aim of this study was to investigate the findings of multidetector-row computed tomography of gastrointestinal perforations and analyze the impact of any imaging signs on the presurgical identification of the perforation site. Methods: We retrospectively reviewed emergency MDCT findings of 93 patients submitted to surgery for gastrointestinal perforation at two different institutions. Two radiologists separately reviewed the emergency MDCT examinations performed on each patient, before and after knowing the surgical diagnosis of the perforation site. A list of findings was considered. Positive predictive values were estimated for each finding with respect to each perforation site, and correspondence analysis (CA) was used to investigate the relationship between the findings and each of the perforation types. Results: We did not find inframesocolic free air in sigmoid colorectal perforations, and in rare cases, only supramesocolic free fluid in gastroduodenal perforations was found. A high PPV of perivisceral fat stranding due to colonic perforation and general distension of upstream loops and collapse of downstream loops were evident in most patients. Conclusions: Our data could offer additional information on the perforation site in the case of doubtful findings to support surgeons, especially in planning a laparoscopic approach.

An unusual cause of peritonitis: Perforation of a gastric carcinoma

Gastric carcinoma perforation is an uncommon consequence that is often missed during the preoperative stage. Perforation may occur at any stage of cancer, but it is more common in late stages. It can also happen early in the illness. Because of the spilled stomach contents, it produces an acute abdominal syndrome. The goal of treatment should be to strike a balance between the emergency situation of peritonitis and oncological surgical techniques. A case of stomach cancer perforation with typical imaging findings is presented.

Multidetector computed tomography: a corner stone imaging modality in evaluation of acute small bowel diseases

Background

The diagnosis of acute small bowel diseases is one of the challenging issues that confronted by the radiologists so accurate diagnosis is essential to determine the appropriate way of management. CT has become the preferred imaging tool to evaluate acute small bowel diseases. Our study aimed to assess the role of MDCT in evaluation of acute abdomen secondary to small bowel origin by identification and differentiation between different acute small bowel pathologies.

Results

Thirty-eight patients presented with acute abdomen of small bowel origin from June 2019 to September 2019. The mean age of incidence was 48 ± 19 years ranged from 4 to 88 years. Males represented by 23 patients (60.5%). Acute exacerbation of inflammatory bowel diseases (Crohn’s disease) represented by (34.2%), small bowel obstruction (31.6%), ischemic bowel diseases (21.1%), small bowel perforation (10.5%) and infectious (TB enteritis) small bowel disease (2.6%). MDCT had an overall high sensitivity (97.3%) in assessment of acute small bowel diseases in correlation with post-operative data and follow-up response to management.

Conclusions

MDCT is a reliable diagnostic imaging tool for assessment of patients with acute abdomen secondary to small bowel origin with high-efficiency in differentiation between different pathological entities that causing acute abdomen.

Postmortem computed tomography differentiation between intraperitoneal decomposition gas and pneumoperitoneum

PURPOSE

The aim of this study is to investigate the ability of postmortem computed tomography (PMCT) to distinguish intraperitoneal decomposition gas from pneumoperitoneum due to intestinal perforation.

METHODS

This retrospective study investigated the factors affecting intraperitoneal gas in two groups of 14 decedents as detected by postmortem CT performed in the Department of Legal Medicine of Hamburg University. The first group died with a cause of death associated with intestinal perforation, and the second group with other different natural causes of death. These factors include postmortem interval, gas volume, gas distribution, radiology alteration index (RAI), and pneumoperitoneum-associated pathology.

RESULTS

The findings of this study showed the appearance of specific gas distribution patterns and a significant increase in gas volumes in the cases of intestinal perforation. Moreover, postmortem interval and the pneumoperitoneum-associated pathology could help distinguish postmortem-generated gas from pneumoperitoneum.

CONCLUSION

Based on the findings of this study, we propose that these findings can improve the proper detection of intestinal perforation cases in the future.

Accuracy of specific free air distributions in predicting the localization of gastrointestinal perforations

PURPOSE

To evaluate the role of specific distributions of free air in predicting the location of gastrointestinal (GI) tract perforation.

MATERIALS AND METHODS

One hundred and fifteen patients with surgically proven GI tract perforation between January 2015 and June 2019 were included in the study. The site of perforation was based on surgical findings in all cases. Two radiologists retrospectively interpreted the computed tomography (CT) images of these patients for extraluminal free air distribution. Perforation sites were demonstrated intraoperatively in all cases and were categorized as follows: stomach and duodenum, jejunum and ileum, proximal colon (cecum, ascending colon, and transverse colon), distal colon (descending colon and sigmoid colon), rectum, and appendix.

RESULTS

There were 79 male and 36 female patients with a mean age of 56.4 years. Periportal, perihepatic, and perigastric free air were statistically significant in predicting gastroduodenal perforation. Mesenteric free air was significant in predicting both small bowel and distal colon perforations. Pelvic free air was statistically significant in distal colon perforations. Periappendiceal free air was found to be a strong predictor of acute perforated appendicitis.

CONCLUSION

Specific free air distributions may help to predict the site of gastrointestinal perforation, which would change the treatment plan.

Multimodality imaging of adult gastric emergencies: A pictorial review

Acute gastric emergencies require urgent surgical or nonsurgical intervention because they are associated with high morbidity and mortality. Imaging plays an important role in diagnosis since the clinical symptoms are often nonspecific and radiologist may be the first one to suggest a diagnosis as the imaging findings are often characteristic. The purpose of this article is to provide a comprehensive review of multimodality imaging (plain radiograph, fluoroscopy, and computed tomography) of various life threatening gastric emergencies.

Development and Validation of a Nomogram for Preoperative Prediction of Localization of Neonatal Gastrointestinal Perforation

Background: Information regarding the localization of gastrointestinal perforation is crucial for the following surgical procedure. This study was to determine the key indicators and develop a prediction model for the localization in neonates with gastrointestinal perforation. Methods: A nomogram to predict the location of neonatal gastrointestinal perforation was developed using a cohort of patients who underwent surgery between July 2009 and May 2021. Baseline variables were analyzed using logistics regression and nomogram developed using significant predictors. The predictive performance of the nomogram was assessed by the concordance index (C-index), calibration curve, and area under the receiver operating characteristic (ROC) curve (AUC). The nomogram was further validated in an integrated external cohort. Results: We investigated the data of 201 patients, of which 65 (32.3%) were confirmed with upper gastrointestinal perforation by surgery. Multivariate logistic regression analysis identified the following as independent predictors: preterm [OR: 5.014 (1.492-18.922)], time of onset [OR: 0.705 (0.582-0.829)], preoperative hemoglobin [OR:1.017 (1.001-1.033)], bloody stool: No [OR: 4.860 (1.270-23.588)], shock [OR: 5.790 (1.683-22.455)] and sepsis: No [OR 3.044 (1.124-8.581)]. Furthermore, the nomogram was effective in predicting the perforation site, with an AUC of 0.876 [95% confidence interval (CI): 0.830-0.923]. Internal validation showed that the average AUC was 0.861. Additionally, the model achieved satisfactory discrimination (AUC, 0.900; 95% CI, 0.826-0.974) and calibration (Hosmer-Lemeshow test, P = 0.4802) in external validation. Conclusions: The nomogram based on the six factors revealed good discrimination and calibration, suggesting good clinical utility. The nomogram could help surgeons predict the location of gastrointestinal perforation before surgery to make a surgical plan.

Spontaneous Rectal Perforation in a Patient with SARS-CoV-2 Infection

Coronavirus disease 2019 (COVID-19) is mostly perceived as a respiratory disease. However, there is increasing evidence of patients showing gastrointestinal symptoms, with increasing rates of presentation according to the severity of the disease. In a few cases, the abdominal involvement of COVID-19 resulted in spontaneous bowel perforation. Here, we present in detail the first case of rectal perforation in a patient with COVID-19.

Diagnosis and management of iatrogenic endoscopic perforations: European Society of Gastrointestinal Endoscopy (ESGE) Position Statement - Update 2020

1:  ESGE recommends that each center implements a written policy regarding the management of iatrogenic perforations, including the definition of procedures that carry a higher risk of this complication. This policy should be shared with the radiologists and surgeons at each center. 2 : ESGE recommends that in the case of an endoscopically identified perforation, the endoscopist reports its size and location, with an image, and statement of the endoscopic treatment that has been applied. 3:  ESGE recommends that symptoms or signs suggestive of iatrogenic perforation after an endoscopic procedure should be rapidly and carefully evaluated and documented with a computed tomography (CT) scan. 4 : ESGE recommends that endoscopic closure should be considered depending on the type of the iatrogenic perforation, its size, and the endoscopist expertise available at the center. Switch to carbon dioxide (CO2) endoscopic insufflation, diversion of digestive luminal content, and decompression of tension pneumoperitoneum or pneumothorax should also be performed. 5 : ESGE recommends that after endoscopic closure of an iatrogenic perforation, further management should be based on the estimated success of the endoscopic closure and on the general clinical condition of the patient. In the case of no or failed endoscopic closure of an iatrogenic perforation, and in patients whose clinical condition is deteriorating, hospitalization and surgical consultation are recommended.

Diagnostic Utility of CT and Fluoroscopic Esophagography for Suspected Esophageal Perforation in the Emergency Department

OBJECTIVE. We evaluated the diagnostic utility of CT in emergency department (ED) patients with suspected esophageal perforation and assessed whether subsequent fluoroscopic esophagography is necessary. MATERIALS AND METHODS. This retrospective study included consecutive adult patients presenting to an urban academic tertiary care ED from January 1, 2000, to August 31, 2017, who underwent CT and fluoroscopic esophagography within 1 calendar day (< 27 hours) of each other for suspected esophageal perforation. The use of oral or IV contrast material and the CT findings (i.e., pneumomediastinum, pleural effusion, pneumothorax, unexplained mediastinal fluid or stranding, esophageal wall air or frank esophageal wall disruption, or extraluminal oral contrast material) were documented. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated. Surgical or procedural intervention results or clinical follow-up results were the reference standard. RESULTS. One hundred three patients met the inclusion criteria. Sensitivity, specificity, PPV, and NPV for diagnosing esophageal perforation were 100.0%, 79.8%, 32.1%, and 100.0%, respectively, with CT and 77.8%, 98.9%, 87.5%, and 97.9% with fluoroscopic esophagography. Combining CT and fluoroscopic esophagography did not improve sensitivity, specificity, PPV, or NPV relative to using CT alone. The true-positive esophageal perforation rate was 8.7% for CT and 6.8% for fluoroscopic esophagography. When CT showed only pneumomediastinum (n = 51) or no pneumomediastinum (n = 14), the NPV of CT was 100.0%. CT with oral contrast material had a PPV of 38.5%, whereas CT without oral contrast material had a PPV of 26.7%. CONCLUSION. CT has a high NPV similar to that of fluoroscopic esophagography and has greater sensitivity than fluoroscopic esophagography for diagnosing suspected esophageal perforation. Fluoroscopic esophagrams do not provide additional information that changes clinical management beyond the information that CT provides. In ED patients with suspected esophageal perforation, CT with oral contrast material should be considered the initial imaging examination and can obviate fluoroscopic esophagography.

Free abdominal gas on computed tomography in the emergency department: aetiologies and association between amount of free gas and mortality

INTRODUCTION

Free abdominal gas is an important finding with major clinical implications. However, data on the aetiologies and prognosis of patients with free gas are scarce. Our primary aim was to describe the sources of free abdominal gas on emergency department (ED) computed tomography (CT). The secondary aim was to evaluate the association between the amount of free gas and all-cause mortality.

METHODS

All patients who underwent CT in the ED between February 2012 and February 2019 with free abdominal gas were included in the study. A scoring system was used to assess the amount of free gas: small - gas bubbles; medium - any gas pocket ≤2cm in diameter; large - any gas pocket >2cm. Data were collected from laboratory and clinical assessment regarding the source of free gas and all-cause mortality.

RESULTS

A total of 372 patients had free abdominal gas. Colonic diverticulitis was the most common aetiology among those with a small or medium amount of free gas (81/250 [32.4%] and 12/71 [16.9%] respectively). For patients with a large amount of gas, peptic disease was the most common aetiology (11/51 [21.6%]). Three-quarters of the patients (280/372, 75.2%) had the source of free gas identified during ED admission. Ninety-day mortality rates were 7.2%, 9.9% and 21.6% for patients with small, medium and large amounts of gas respectively (p=0.007).

CONCLUSIONS

Colonic diverticulitis was the most common source of free abdominal gas and peptic disease was the most common cause of a large amount of free gas. Mortality rates correlated with the amount of gas and were significantly higher in patients with a large amount.

Gastrointestinal perforation: clinical and MDCT clues for identification of aetiology

Gastrointestinal tract (GIT) perforation is a common medical emergency associated with considerable mortality, ranging from 30 to 50%. Clinical presentation varies: oesophageal perforations can present with acute chest pain, odynophagia and vomiting, gastroduodenal perforations with acute severe abdominal pain, while colonic perforations tend to follow a slower progression course with secondary bacterial peritonitis or localised abscesses. A subset of patients may present with delayed symptoms, abscess mimicking an abdominal mass, or with sepsis.

Direct multidetector computed tomography (MDCT) findings support the diagnosis and localise the perforation site while ancillary findings may suggest underlying conditions that need further investigation following primary repair of ruptured bowel. MDCT findings include extraluminal gas, visible bowel wall discontinuity, extraluminal contrast, bowel wall thickening, abnormal mural enhancement, localised fat stranding and/or free fluid, as well as localised phlegmon or abscess in contained perforations.

The purpose of this article is to review the spectrum of MDCT findings encountered in GIT perforation and emphasise the MDCT and clinical clues suggestive of the underlying aetiology and localisation of perforation site.

CT diagnosis of non-traumatic gastrointestinal perforation: an emphasis on the causes

Gastrointestinal tract (GI) perforations can occur due to various causes such as trauma, iatrogenic factor, infectious condition, peptic ulcer, inflammatory disease, or a neoplasm. Because GI perforations represent an emergency and life-threatening condition, prompt diagnosis and surgical treatment are required in most cases. However, according to the underlying causes of GI perforations, additional treatment strategies may be needed. Adjuvant chemotherapy or immunotherapy may be required in various GI neoplasms such as adenocarcinoma, lymphoma or gastrointestinal stromal tumor. Inflammatory bowel disease is a chronic disease repeating cycle of intermittent, thus appropriate medical treatment and periodic follow-up are also required. Moreover, vascular intervention may have a role in some cases of mesenteric ischemia associated with mesenteric artery occlusion. Recently, computed tomography (CT) has been the first choice for patients with suspected GI perforations, because CT plays an important role in the accurate assessment of the perforation site, the pathology causing the perforation and the ensuing complications. This review will illustrate characteristic CT findings that differentiate underlying pathologies causing GI perforations to help clinicians decision-making regarding an optimal treatment plan.

C-Reactive Protein in the Prediction of Localization of Gastrointestinal Perforation

AIM

Information regarding the localization of the anatomic site of gastrointestinal (GI) tract perforation is essential for the following surgical procedure. The purpose of this study was to evaluate the significance of C-reactive protein (CRP) and other circulating markers for the prediction of the localization of intra-abdominal hollow organ perforation.

METHODS

Measurements of serum markers were analyzed in 423 patients with GI tract perforations, who were divided according to the intraoperative diagnosis into colorectal and upper GI tract perforation groups.

RESULTS

Levels of CRP were higher in patients with colorectal perforations than in upper GI tract perforations (p < 0.001). Moreover, high levels of CRP were associated with increased mortality of patients with hollow organ perforations (p = 0.009), which was largely driven by the subset of patients with perforations of the upper GI tract (p = 0.001).

CONCLUSION

Increased CRP levels predict worse clinical outcome in patients with intra-abdominal hollow organ perforations and are associated with perforations in the colorectal tract. Thus, CRP might be a useful marker for preoperative risk stratification and prediction of the localization of the perforation site.

Multidetector CT findings in gastrointestinal tract perforation that can help prediction of perforation site accurately

AIM

To assess the accuracy, sensitivity, and specificity of multidetector computed tomography (MDCT) findings by comparing the locations of free air in the abdomen and imaging findings with the site of gastrointestinal perforation.

MATERIALS AND METHODS

Ninety-three patients with acute abdominal pain who visited the emergency department between January 2015 and October 2018 were included in the study. There were 59 male and 34 female patients with a mean age of 50.5 years. The site of perforation was based on surgical findings in all cases.

RESULTS

Among specific air distributions, periportal free air and subphrenic free air were statistically significant in differentiating upper gastrointestinal tract perforation. Whereas free air in the minor pelvis, right lower quadrant free air, left lower quadrant free air, and air in the mesentery were statistically significant in differentiation of lower gastrointestinal tract perforation.

CONCLUSION

Multidetector findings may help to predict the site of gastrointestinal perforation, which would change the treatment plan.

Diagnostic effectiveness of preoperative water-soluble contrast enema in colorectal perforation

OBJECTIVE

To evaluate the diagnostic usefulness of performing a preoperative water-soluble contrast enema (WSCE) before emergency surgery for colorectal perforation.

METHODS

We retrospectively reviewed 68 consecutive patients who underwent a preoperative WSCE before emergency surgery for colorectal perforation during the period from January 2011 to December 2017. Clinical characteristics and inflammatory biomarkers were compared between patients with Hinchey I-II versus those with Hinchey III-IV.

RESULTS

WSCE leakage occurred in 27 of 68 patients (39.7%). Univariate analysis showed that the two groups (Hinchey I-II and Hinchey III-IV) significantly differed regarding age, perforation site, cause of perforation, American Society of Anesthesiologists grade, presence or absence of WSCE leakage, and white blood cell count. Multivariable analysis revealed that WSCE leakage was a predictor of Hinchey III-IV, with an odds ratio of greater than 24 (P = 0.002). The sensitivity and specificity of WSCE leakage for differentiating those with Hinchey III-IV from those with Hinchey I-II were 76.5% and 97.1%, respectively.

CONCLUSIONS

This retrospective study indicates that preoperative WSCE before emergency surgery is a useful tool for predicting the presence of Hinchey III-IV in patients with colorectal perforation.

Sonographic and CT imaging features of intestinal perforation from a pill and packing: A case report

RATIONALE

Sharp foreign bodies such as toothpicks or chicken bones can lead to intestinal perforation. Small intestinal perforation secondary to foreign body ingestion is usually manifested as an acute abdomen without a history of trauma. Here we describe the diagnosis and treatment of a case of small bowel perforation caused by an ingested pill and its outer packing.

PATIENT CONCERNS

An 84 years old male patient complained of right lower abdominal pain for 4 days and the pain was becoming progressively worse.

DIAGNOSES

The patient, who has Alzheimer's disease, mistakenly took the pill (oxiracetam) without removing the outer packaging. This resulted in perforation of the small intestine.

INTERVENTIONS

During the ultrasound examination, the scanning physician discovered that the abnormal sonographic findings present could not be explained by the leading diagnosis of perforation of the small intestine at the time. This led the physician to suspect small bowel perforation secondary to a foreign body. The subsequent computerized tomography (CT) examination further confirmed the ultrasound findings.

OUTCOMES

Emergency laparotomy was performed and the foreign body was removed. After the surgical procedure, the patient resumed anti-inflammatory treatment (Cefoxitin sodium 2000mg tid) and rehydration therapy (Sodium Chloride Solution 100mL tid).

LESSONS

Because ingestion of foreign bodies of this type is relatively rare, when patients cannot provide an accurate history, diagnosis can be quite difficult. In this paper, the imaging features associated with intestinal perforation secondary to foreign body ingestion on ultrasound and CT are described. This series of events demonstrate how imaging findings can guide and alter a clinician's decision-making.

A Case of Unresolved and Worsening Retroperitoneal Abscess

Retroperitoneal abscess is a rare condition which is difficult to diagnose and treat because of its insidious onset. Herein, we present a case of retroperitoneal abscess secondary to a perforation that occurred during an ERCP. A 54-year-old female patient was admitted to an outside hospital with gallstone pancreatitis and underwent ERCP with sphincterotomy followed by laparoscopic cholecystectomy. An abdominal CT scan was performed at the outside hospital 10 days later for worsening abdominal pain which showed multiple loculated pockets in the right upper and lower quadrant. Her condition improved after IV antibiotics and percutaneous drainage. Her symptoms recurred a month later and she presented to our hospital. Repeat abdominal CT scan at our hospital revealed recurrence of her abscesses. Multiple drains were placed and the abscess cavity was washed out without much improvement. EGD revealed a small mucosal defect in the distal portion of the duodenal bulb which was closed successfully using an over-the-scope clip. Repeat CT scan after 8 weeks from the endoscopic closure showed near complete resolution of the abscess. ERCP-associated perforation is a rare complication and can be challenging to diagnose and treat; prompt recognition is mandatory for favorable prognosis. Our patient was managed successfully via nonsurgical approach.

2017 WSES guidelines for the management of iatrogenic colonoscopy perforation

Iatrogenic colonoscopy perforation (ICP) is a severe complication that can occur during both diagnostic and therapeutic procedures. Although 45–60% of ICPs are diagnosed by the endoscopist while performing the colonoscopy, many ICPs are not immediately recognized but are instead suspected on the basis of clinical signs and symptoms that occur after the endoscopic procedure. There are three main therapeutic options for ICPs: endoscopic repair, conservative therapy, and surgery. The therapeutic approach must vary based on the setting of the diagnosis (intra- or post-colonoscopy), the type of ICP, the characteristics and general status of the patient, the operator’s level of experience, and surgical device availability.

Although ICPs have been the focus of numerous publications, no guidelines have been created to standardize the management of ICPs. The aim of this article is to present the World Society of Emergency Surgery (WSES) guidelines for the management of ICP, which are intended to be used as a tool to promote global standards of care in case of ICP. These guidelines are not meant to substitute providers’ clinical judgment for individual patients, and they may need to be modified based on the medical team’s level of experience and the availability of local resources.

Imaging Manifestations of Peptic Ulcer Disease on Computed Tomography

Although the overall prevalence of peptic ulcer disease (PUD) has decreased in modern times, its actual incidence may be underestimated owing to the nonspecific clinical presentations patients' manifest. The potential lethal complications that can result from PUD include life-threatening abdominal hemorrhage and bowel perforation that result in significant morbidity and mortality. Computed tomography (CT) imaging historically lacks specificity in detecting PUD-related pathology in the stomach and proximal small bowel segments. Therefore, these are potential pitfalls in the radiologist's search pattern on abdominopelvic CT imaging. This article highlights imaging features of uncomplicated PUD on CT imaging in order to allow for early detection of this disease process on imaging and the prevention of potential high-grade complications by recommending esophagogastroduodenoscopy.

Nontraumatic large bowel perforation: spectrum of etiologies and CT findings

Large bowel perforation is an abdominal emergency that results from a wide range of etiologies. Computed tomography is the most reliable modality in detecting the site of large bowel perforation. The diagnosis is made by identifying direct CT findings such as extraluminal gas or contrast and discontinuity along the bowel wall. Indirect CT findings can help support the diagnosis, and include bowel wall thickening, pericolic fat stranding, abnormal bowel wall enhancement, abscess, and a feculent collection adjacent to the bowel. Common etiologies that cause large bowel perforation are colon cancer, foreign body aspiration, stercoral colitis, diverticulitis, ischemia, inflammatory and infectious colitides, and various iatrogenic causes. Recognizing a large bowel perforation on CT can be difficult at times, and there are various entities that may be misinterpreted as a colonic perforation. The purpose of this article is to outline the MDCT technique used for evaluation of suspected colorectal perforation, discuss relevant imaging findings, review common etiologies, and point out potential pitfalls in making the diagnosis of large bowel perforation.

Acute Bowel Computed Tomography

Acute abdominal pain is a common presenting complaint in the emergency department. Increasingly, computed tomography is utilized for evaluating these patients. Radiologists are therefore expected to be familiar with the pertinent clinical and radiologic information related to acute bowel pathology. This primer will review the need-to-know and latest updates related to computed tomography evaluation of acute bowel pathology.

Can multidetector CT detect the site of gastrointestinal tract injury in trauma? - A retrospective study

PURPOSE

We aimed to assess the performance of computed tomography (CT) in localizing site of traumatic gastrointestinal tract (GIT) injury and determine the diagnostic value of CT signs in site localization.

METHODS

CT scans of 97 patients with surgically proven GIT or mesenteric injuries were retrospectively reviewed by radiologists blinded to surgical findings. Diagnosis of either GIT or mesenteric injuries was made. In patients with GIT injuries, site of injury and presence of CT signs such as focal bowel wall hyperenhancement, hypoenhancement, wall discontinuity, wall thickening, extramural air, intramural air, perivisceral infiltration, and active vascular contrast leak were evaluated.

RESULTS

Out of 97 patients, 90 had GIT injuries (70 single site injuries and 20 multiple site injuries) and seven had isolated mesenteric injury. The overall concordance between CT and operative findings for exact site localization was 67.8% (61/90), partial concordance rate was 11.1% (10/90), and discordance rate was 21.1% (19/90). For single site localization, concordance rate was 77.1% (54/70), discordance rate was 21.4% (15/70), and partial concordance rate was 1.4% (1/70). In multiple site injury, concordance rate for all sites of injury was 35% (7/20), partial concordance rate was 45% (9/20), and discordance rate was 20% (4/20). For upper GIT injuries, wall discontinuity was the most accurate sign for localization. For small bowel injury, intramural air and hyperenhancement were the most specific signs for site localization, while for large bowel injury, wall discontinuity and hypoenhancement were the most specific signs.

CONCLUSION

CT performs better in diagnosing small bowel injury compared with large bowel injury. CT can well predict the presence of multiple site injury but has limited performance in exact localization of all injury sites.

Nonmalignant gastric causes of acute abdominal pain on MDCT: a pictorial review

Acute abdominal pain is a common indication for imaging. The stomach may be poorly assessed or overlooked on multidetector computed tomography (MDCT), despite the high prevalence of gastric pathology as the source of abdominal pain. We review the pathophysiology, imaging features, and clinical management of common and uncommon nonmalignant gastric conditions on MDCT. As the stomach is often difficult to assess on MDCT, and pathology overlooked, corresponding increased awareness of gastric causes of pain is critical for radiologists to accurately interpret imaging in the setting of acute abdominal pain.

Multidetector computed tomography in the evaluation of pediatric acute abdominal pain in the emergency department

The accurate diagnosis of pediatric acute abdominal pain is one of the most challenging tasks in the emergency department (ED) due to its unclear clinical presentation and non-specific findings in physical examinations, laboratory data, and plain radiographs. The objective of this study was to evaluate the impact of abdominal multidetector computed tomography (MDCT) performed in the ED on pediatric patients presenting with acute abdominal pain. A retrospective chart review of children aged <18 years with acute abdominal pain who visited the emergency department and underwent MDCT between September 2004 and June 2007 was conducted. Patients with a history of trauma were excluded. A total of 156 patients with acute abdominal pain (85 males and 71 females, age 1-17 years; mean age 10.9 ± 4.6 years) who underwent abdominal MDCT in the pediatric ED during this 3-year period were enrolled in the study. One hundred and eighteen patients with suspected appendicitis underwent abdominal MDCT. Sixty four (54.2%) of them had appendicitis, which was proven by histopathology. The sensitivity of abdominal MDCT for appendicitis was found to be 98.5% and the specificity was 84.9%. In this study, the other two common causes of nontraumatic abdominal emergencies were gastrointestinal tract (GI) infections and ovarian cysts. The most common etiology of abdominal pain in children that requires imaging with abdominal MDCT is appendicitis. MDCT has become a preferred and invaluable imaging modality in evaluating uncertain cases of pediatric acute abdominal pain in ED, in particular for suspected appendicitis, neoplasms, and gastrointestinal abnormalities.

Predicting the amount of intraperitoneal fluid accumulation by computed tomography and its clinical use in patients with perforated peptic ulcer

The correlation between the amount of peritoneal fluid and clinical parameters in patients with perforated peptic ulcer (PPU) has not been investigated. The authors' objective was to derive a reliable formula for determining the amount of peritoneal fluid in patients with PPU before surgery, and to evaluate the correlation between the estimated amount of peritoneal fluid and clinical parameters. We investigated 62 consecutive patients who underwent emergency surgery for PPU, and in whom prediction of the amount of accumulated intraperitoneal fluid was possible by computed tomography (CT) using the methods described by Oriuchi et al. We examined the relationship between the predicted amount of accumulated intraperitoneal fluid and that measured during surgery, and the relationship between the amount of fluid predicted preoperatively or measured during surgery and several clinical parameters. There was a significant positive correlation between the amount of fluid predicted by CT scan and that measured during surgery. When patients with gastric ulcer and duodenal ulcer were analyzed collectively, the predicted amount of intraperitoneal fluid and the amount measured during surgery were each associated with the period from onset until CT scan, perforation size, the Mannheim peritoneal index, and the severity of postoperative complications according to the Clavien-Dindo classification. Our present results suggest that the method of Oriuchi et al is useful for predicting the amount of accumulated intraperitoneal fluid in patients with PPU, and that this would be potentially helpful for treatment decision-making and estimating the severity of postoperative complications.

From esophagus to rectum: a comprehensive review of alimentary tract perforations at computed tomography

Gastrointestinal (GI) tract perforation is a life-threatening condition that can occur at any site along the alimentary tract. Early perforation detection and intervention significantly improves patient outcome. With a high sensitivity for pneumoperitoneum, computed tomography (CT) is widely accepted as the diagnostic modality of choice when a perforated hollow viscus is suspected. While confirming the presence of a perforation is critical, clinical management and surgical technique also depend on localizing the perforation site. CT is accurate in detecting the site of perforation, with segmental bowel wall thickening, focal bowel wall defect, or bubbles of extraluminal gas concentrated in close proximity to the bowel wall shown to be the most specific findings. In this article, we will present the causes for perforation at each site throughout the GI tract and review the patterns that can lead to prospective diagnosis and perforation site localization utilizing CT images of surgically proven cases.

Pneumoretroperitoneum Associated with "Dirty Mass": An Unusual Case of Rectal Perforation

Perforation of the rectum requires early recognition and treatment. The diagnosis of rectal perforation is sometimes difficult owing to non specific clinical presentation, especially in elderly patients, in whom, in case of acute abdomen, Computed Tomography (CT) is increasing used as first diagnostic procedure [1]. Several CT signs of gastrointestinal perforation have been described [2, 3]. Recently another CT finding related to colonic perforation called “ dirty mass” has been reported [4]. We present a case of extraperitoneal rectal perforation secondary to colonoscopy in which CT demonstrated the presence of a focal collection of extraluminal fecal matter (“dirty mass”) associated with pneumoretroperitoneum.

Multimodality approach for imaging of non-traumatic acute abdominal emergencies

"Acute abdomen" includes spectrum of medical and surgical conditions ranging from a less severe to life-threatening conditions in a patient presenting with severe abdominal pain that develops over a period of hours. Accurate and rapid diagnosis of these conditions helps in reducing related complications. Clinical assessment is often difficult due to availability of over-the-counter analgesics, leading to less specific physical findings. The key clinical decision is to determine whether surgical intervention is required. Laboratory and conventional radiographic findings are often non-specific. Thus, cross-sectional imaging plays a pivotal role for helping direct management of acute abdomen. Computed tomography is the primary imaging modality used for these cases due to fast image acquisition, although US is more specific for conditions such as acute cholecystitis. Magnetic resonance imaging or ultrasound is very helpful in patients who are particularly sensitive to radiation exposure, such as pregnant women and pediatric patients. In addition, MRI is an excellent problem-solving modality in certain conditions such as assessment for choledocholithiasis in patients with right upper quadrant pain. In this review, we discuss a multimodality approach for the usual causes of non-traumatic acute abdomen including acute appendicitis, diverticulitis, cholecystitis, and small bowel obstruction. A brief review of other relatively less frequent but important causes of acute abdomen, such as perforated viscus and bowel ischemia, is also included.

Multidetector CT diagnosis of non-traumatic gastroduodenal perforation

INTRODUCTION

To identify reliable CT features and assess the diagnostic performance of 64-multidetector CT (MDCT) in diagnosing non-traumatic gastroduodenal perforation (GDP).

METHODS

We retrospectively reviewed 136 CT scans of patients with surgically proven non-traumatic gastrointestinal perforation during 7 years. 92 patients had GDP and 44 patients had other sites of perforation. CT features of perforation were evaluated and the sensitivity, specificity and likelihood ratios of each CT feature were estimated.

RESULTS

The cause of GDP was peptic ulcer in 90 patients, gastric cancer in one patient, and foreign body of duodenal diverticulum in one patient. Extraluminal gas (97%) was most common CT feature of GDP, following by fluid or fat strand along gastroduodenum (89%), ascites (89%), wall defect and/or ulcer (84%), and wall thickening (72%). Of CT features, wall defect and/or ulcer showed the best positive likelihood ratios for GDP (36.83). Wall thickening also showed high positive likelihood ratios (10.52). Combined, these CT features showed 95% sensitivity and 93% specificity for localization of perforation site of GDP.

CONCLUSION

MDCT is useful in diagnosis of presence and site of GDP. Wall defect and/or ulcer and wall thickening have a high positive predictive value for localization of perforation site.

Imaging Assessment of Gastroduodenal Perforations

Gastroduodenal perforation is an emergency situation that usually requires early recognition and well-timed surgical treatment. It can arise from different natural, iatrogenic, or traumatic causes, and it can present with various symptoms especially in the early phase. This article reviews the role of the different imaging techniques in the diagnosis of gastroduodenal perforation, focusing on the direct and indirect signs that are encountered in conventional radiography and computed tomography; our personal experience is also provided.

Role of Multidetector Computed Tomography in the Diagnosis of Colorectal Perforations

Colonic perforations can be classified into perforations that occur at the site of a localized pathologic process and cecal perforations that occur secondary to distal colonic obstructions. Rectal perforations may result from foreign bodies inserted into the rectum; moreover, deep rectal biopsies, polypectomy, improper cleansing enema, or thermometer placement may also lead to rectal perforation. Correct identification of the cause and site of the perforation is crucial for appropriate management and surgical planning. Multidetector row computed tomography has a pivot role in planning the type of operative treatment, the prognosis, and in assessing those patients who have clinical symptoms of peritonitis but no radiographic signs of perforation.

Perforated Appendicitis: Assessment With Multidetector Computed Tomography

Appendicitis is one of the most common abdominal surgical emergencies. In some cases, the correct diagnosis may be challenging, owing to different conditions that can mimic this pathology. In this context, abdominal computed tomography (CT) is the imaging modality of choice, leading to an accurate diagnosis and to a reduction in unnecessary laparotomies. The diagnosis of perforated appendix is crucial, but the detection of the perforation signs by CT may not be so simple in the early process. The aim of this article is to review the multiple detector CT signs of perforated appendicitis.

MDCT diagnosis of gastroduodenal ulcers: key imaging features with endoscopic correlation

Although the overall prevalence of peptic ulcer disease (PUD) and related hospitalizations are decreasing, the initial presentation of complicated PUD on CT remains common. It, therefore, remains critical for radiologists to recognize the findings of PUD at CT for initial diagnosis. While the CT findings of complicated PUD have been previously described in the literature, the CT findings of uncomplicated PUD have not been well documented. Furthermore, although CT is certainly not the diagnostic evaluation of choice for patients with suspected uncomplicated PUD, many patients with PUD will nonetheless present to the emergency department with unexplained abdominal pain and undergo MDCT evaluation as the initial diagnostic test. Therefore, recognizing the MDCT findings of uncomplicated PUD can help appropriately direct patient management, and help prevent the development of complications. To facilitate improved recognition of PUD on abdominal CT, we present an overview of the CT findings of both uncomplicated and complicated PUD, as well as several diagnostic pitfalls which can result in misdiagnosis from peptic ulcer mimics.

Perforated peptic ulcer

Perforated peptic ulcer is a common emergency condition worldwide, with associated mortality rates of up to 30%. A scarcity of high-quality studies about the condition limits the knowledge base for clinical decision making, but a few published randomised trials are available. Although Helicobacter pylori and use of non-steroidal anti-inflammatory drugs are common causes, demographic differences in age, sex, perforation location, and underlying causes exist between countries, and mortality rates also vary. Clinical prediction rules are used, but accuracy varies with study population. Early surgery, either by laparoscopic or open repair, and proper sepsis management are essential for good outcome. Selected patients can be managed non-operatively or with novel endoscopic approaches, but validation of such methods in trials is needed. Quality of care, sepsis care bundles, and postoperative monitoring need further assessment. Adequate trials with low risk of bias are urgently needed to provide better evidence. We summarise the evidence for perforated peptic ulcer management and identify directions for future clinical research.