Evolution of imaging for abdominal perforation

Imaging Patients With Alimentary Tract Perforation: Literature Review

Alimentary tract perforation is a frequent emergency condition. Imaging plays an important role to make an accurate diagnosis, defining the presence, the level, and the cause of the perforation, essential information to enable the most correct therapeutic choice. Plain radiography is generally performed as the first choice. In case of a clinically suspected bowel perforation, not detected on x-ray imaging, the contribution of computed tomography is essential. Magnetic resonance is not yet widely used in diagnostic workup of patients with acute abdominal pain, but it can be useful in the differential diagnosis of acute abdomen in specific patients (pregnancy and pediatric patients).

Stercoral Perforation of the Colon during Pregnancy: A Case Report and Review of the Literature

Stercoral perforation of the colon, though rare, is associated with high mortality. Review of the literature identified only three prior cases reported during pregnancy. We report a case on a multiparous female presenting at 31 weeks of gestation with acute abdominal pain. Computed tomography suggested a sigmoid colon perforation. An urgent exploratory laparotomy was performed where feculent peritonitis and a stercoral perforation of the sigmoid colon was confirmed. A cesarean delivery and sigmoid colectomy with descending end colostomy was performed. While the newborn had an uncomplicated course, the mother developed an intra-abdominal abscess requiring operative management.

The emergency room diagnosis of gastrointestinal tract perforation: the role of CT

Computed tomography (CT) plays an important role in the evaluation of patients presenting to the emergency department with a suspected spontaneous gastrointestinal tract (GIT) perforation. Prospective identification of the site of perforation helps the emergency department physician plan the appropriate treatment in a potentially unstable patient. The purpose of this pictorial essay is to review the CT approach a radiologist should take when evaluating the patient with suspected perforation in the emergent setting. A series of patients presenting to the emergency department with surgically proven GIT perforations were retrospectively reviewed, and key images were obtained. For the purposes of this review, the anatomy of the abdominal cavity in relation to sites of GIT perforation will be discussed. CT findings of perforation will be described, including free intraperitoneal/extraperitoneal air, bowel wall discontinuity, and localized inflammatory changes. The use of a bone window setting to increase the free air conspicuity will be emphasized. The mimics of pneumoperitoneum will be demonstrated, including pneumothorax, pneumomediastinum, and venous air. Using a systematic approach, CT can precisely determine the presence and site of a gastrointestinal perforation in a majority of patients. This greatly assists the surgeon in planning the correct surgical approach.

Spontaneous free perforation of the small intestine in adults

Spontaneous free perforation of the small intestine is uncommon, especially if there is no prior history of visceral trauma. However, free, even recurrent, perforation may complicate a defined and established clinical disorder, such as Crohn’s disease. In addition, free perforation may be the initial clinical presentation of an occult intestinal disorder, such as a lymphoma complicating celiac disease, causing diffuse peritonitis and an acute abdomen. Initial diagnosis of the precise cause may be difficult, but now has been aided by computerized tomographic imaging. The site of perforation may be helpful in defining a cause (e.g., ileal perforation in Crohn’s disease, jejunal perforation in celiac disease, complicated by lymphoma or collagenous sprue). Urgent surgical intervention, however, is usually required for precise diagnosis and treatment. During evaluation, an expanding list of other possible causes should be considered, even after surgery, as subsequent management may be affected. Free perforation may not only complicate an established intestinal disorder, but also a new acute process (e.g., caused by different infectious agents) or a longstanding and unrecognized disorder (e.g., congenital, metabolic and vascular causes). Moreover, new endoscopic therapeutic and medical therapies, including use of emerging novel biological agents, have been complicated by intestinal perforation. Recent studies also support the hypothesis that perforation of the small intestine may be genetically-based with different mutations causing altered connective tissue structure, synthesis and repair.

Yeast hydrolysate can reduce body weight and abdominal fat accumulation in obese adults

OBJECTIVE

The aim of this study was to examine the effect of yeast hydrolysate on the abdominal fat in obese humans.

METHODS

We observed the effects of yeast hydrolysate that had a molecular weight below 10 kDa on the anti-abdominal fat accumulation in obese men and women ages 20 to 50 y for 10 wk. The abdominal fat mass was assessed by computed tomographic scans.

RESULTS

By the sixth week, the reductions in energy intake in the yeast group (yeast hydrolysate 1 g/d) were significantly greater than those in the control group (placebo 1 g/d) (P < 0.05). The body weight and body mass index (BMI) were significantly reduced by week 10 compared with baseline in the yeast group, and these differences were significantly greater than those in the control group: body weight 0.83 kg versus -2.60 k g (P < 0.001), BMI 0.29 kg/m(2) versus -0.90 kg/m(2) (P < 0.001). Despite the increased loss of body weight in the yeast group, lean body mass did not significantly differ between the two groups. Body fat mass in the control group did not significantly change between baseline and week 10. However, the yeast group lost a significant amount of body fat mass after 10 wk of treatment (P < 0.01). The differences in abdominal fat thickness and abdominal circumference between the two groups were significant after 10 wk of treatment (P < 0.001). The total abdominal fat area in the yeast group was significantly lower than in the control group after 10 wk of treatment (-7.06 cm(2) versus -17.34 cm(2); P < 0.01).

CONCLUSIONS

Yeast hydrolysate can reduce body weight and the accumulation of abdominal fat without an adverse effect on lean body mass in obese adults, regardless of sex, via the reduction of energy intake.

Gastrointestinal tract perforation: evaluation of MDCT according to perforation site and elapsed time

OBJECTIVES

To evaluate multidetector computed tomography (MDCT) for the prediction of perforation site according to each gastrointestinal (GI) tract site and elapsed time.

METHODS

One hundred and sixty-eight patients who underwent MDCT before laparotomy for GI tract perforation were enrolled and allocated to an early or late lapse group based on an elapsed time of 7 h. Two reviewers independently evaluated the perforation site and assessed the following CT findings: free air location, mottled extraluminal air bubbles, focal bowel wall discontinuity, segmental bowel wall thickening, perivisceral fat stranding and localised fluid collection.

RESULTS

The overall diagnostic accuracy was 91.07 % and 91.67 % for reviewers 1 and 2, respectively, with excellent agreement (kappa 0.86). Accuracies (98.97 % and 97.94 %) and agreements (kappa 0.894) for stomach and duodenum perforation were higher than for other perforation sites. Strong predictors of perforation at each site were: focal bowel wall discontinuity for stomach, duodenal bulb and left colon, mottled extraluminal air bubbles for retroperitoneal duodenum and right colon, and segmental bowel wall thickening for small bowel. The diagnostic accuracy was not different between the early- and late-lapse groups.

CONCLUSIONS

MDCT can accurately predict upper GI tract perforation with high reliability. Elapsed time did not affect the accuracy of perforation site prediction.

KEY POINTS

Perforation of the stomach and duodenum can be accurately predicted with MDCT. Knowledge of CT findings predicting perforation site can improve diagnostic accuracy. Elapsed time does not significantly affect accuracy in predicting perforation sites.

Free air on plain film: Do we need a computed tomography too?

Context:

Standard teaching is that patients with pneumoperitoneum on plain X-ray and clinical signs of abdominal pathology should undergo urgent surgery. It is unknown if abdominal computed tomography (CT) provides additional useful information in this scenario.

Aims:

The aim of this study is to determine whether or not CT scanning after identification of pneumoperitoneum on plain X-ray changes clinical management or outcomes.

Settings and Design:

Retrospective study carried out over 4 years at a tertiary care academic medical center. All patients in our acute care surgery database with pneumoperitoneum on plain X-ray were included. Patients who underwent subsequent CT scanning (CT group) were compared with patients who did not (non-CT group).

Statistical Analysis Used:

The Wilcoxon rank-sum test, t-test and Fisher's exact test were used as appropriate to compare the groups.

Results:

There were 25 patients in the non-CT group and 18 patients in the CT group. There were no differences between the groups at presentation. All patients in the non-CT group underwent surgery, compared with 83% (n = 15) of patients in the CT group (P = 0.066). 16 patients in the non-CT and 11 patients in the CT group presented with peritonitis and all underwent surgery regardless of group. For patients undergoing surgery, there were no differences in outcomes between the groups. After X-ray, patients undergoing CT required 328.0 min to arrive in the operating room compared with 136.0 min in the non-CT group (P = 0.007).

Conclusions:

In patients with pneumoperitoneum on X-ray and peritonitis on physical exam, CT delays surgery without providing any measurable benefit.

Less Common Nontraumatic Bowel Perforations: Diagnosis and Management through a Retrospective Study

Nontraumatic bowel perforation has always been a consideration because of associated morbidity and mortality. The aim of this study is to define etiologies, treatment, and outcomes as well as to highlight difficulties in the diagnosis and management of nontraumatic bowel perforation. We conducted a retrospective study of 35 patients with less common nontraumatic bowel perforations hospitalized during a six-year period. The most common cause was ulcerative colitis (34.3%). Abdominal pain was the constant symptom. Physical examination showed signs of peritoneal irritation in 29 cases. The abdominal radiograph failed to reveal abnormal findings in two patients; the abdominal computed tomography scan confirmed the diagnosis in all cases. Twenty patients (57.1%) were operated on within 24 hours of developing perforation, whereas seven patients (20%) were initially misdiagnosed. Most of the perforations were located only in the large intestine (60%). There was only one perforation in 25 patients (71.5%) and two or more perforations in 10 patients (28.5%). Many less common diseases are responsible for the spontaneous perforation of the bowel. Early diagnosis before the patient's general condition deteriorates decreases mortality and morbidity rates. Adequate resuscitation and emergency laparotomy followed by resection with or without anastomosis remains the treatment of choice.

Preoperative staging of perforated diverticulitis by computed tomography scanning

Background

Treatment of perforated diverticulitis depends on disease severity classified according to Hinchey’s preoperative classification. This study assessed the accuracy of preoperative staging of perforated diverticulitis by computerized tomography (CT) scanning.

Methods

All patients who presented with perforated diverticulitis between 1999 and 2009 in two teaching hospitals of Rotterdam, the Netherlands, and in addition had a preoperative CT scan within 24 h before emergency surgery were included. Two radiologists reviewed all CT scans and were asked to classify the severity of the disease according to the Hinchey classification. The CT classification was compared to Hinchey’s classification at surgery.

Results

Seventy-five patients were included, 48 of whom (64 %) were classified Hinchey 3 or 4 perforated diverticulitis during surgery. The positive predictive value of preoperative CT scanning for different stages of perforated diverticulitis ranged from 45 to 89 %, and accuracy was between 71 and 92 %. The combination of a large amount of free intra-abdominal air and fluid was strongly associated with Hinchey 3 or 4 and therefore represented a reliable indicator for required surgical treatment.

Conclusions

The accuracy of predicting Hinchey’s classification by preoperative CT scanning is not very high. Nonetheless, free intra-abdominal air in combination with diffuse fluid is a reliable indication for surgery as it is strongly associated with perforated diverticulitis with generalized peritonitis. In 42 % of cases, Hinchey 3 perforated diverticulitis is falsely classified as Hinchey 1 or 2 by CT scanning.

Erect chest radiography in the setting of the acute abdomen: essential tool or an unnecessary waste of resources?

INTRODUCTION

It has been suggested that changes to the training schemes of junior doctors and the increased pressure on emergency departments to manage their patients within a limited time might increase the number of unnecessary investigations performed on emergency admission patients. This, in turn, may lead to an increased number of investigations with normal results. In this study we try to analyse the role of the chest X-ray (CXR) as a diagnostic tool in patients presenting with acute abdominal pain.

PATIENTS AND METHODS

A retrospective study was performed of the request forms and results of all chest radiography performed on patients admitted on the emergency surgical intake with acute abdominal pain through utilisation of the prospectively maintained electronic radiology database. The indications were compared to the guidelines published by the Royal College of Radiologists (RCR) which have been adopted as the standard of care.

RESULTS

A total of 334 chest X-rays were identified of which only 23 (7%) had new findings. Four (1%) patients had free gas under the diaphragm. Of the CXRs, 258 (77%) were reported normal whilst 53 (16%) had old changes which were described in their hospital records and previous radiographs. Of the CXRs with new findings, only 20 were clinically significant and, of these, four (1%) were surgically significant.

CONCLUSIONS

The majority of CXRs performed on emergency surgical admissions with abdominal pain are unnecessary. By obtaining a clear history, performing a thorough clinical examination and following the RCR guidelines most of the CXRs could be avoided. This would lead to less radiation exposure, reduce delays to diagnosis, and provide significant financial savings.