CT diagnosis of occult incisional hernias

The Importance of Surgeon-reviewed Computed Tomography for Incisional Hernia Detection: A Prospective Study

Patients with incisional hernias or abdominal pain are frequently referred with abdominal computed tomography (CT) scans. The purpose of this study was to determine the sensitivity and specificity of a CT radiology report for the detection of incisional hernias. General surgery patients with a history of an abdominal operation and a recent viewable abdominal CT scan were enrolled prospectively. Patients with a stoma, fistula, or soft tissue infection were excluded. The results of the radiology reports were compared with blinded, surgeon-interpreted CT for each patient. Testing characteristics including sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated. One hundred eighty-one patients were enrolled with a mean age of 54 years. Sixty-eight per cent were women. Hernia prevalence was 55 per cent, and mean hernia width was 5.2 cm. The radiology report had a sensitivity and specificity of 79 per cent and 94 per cent, respectively, for hernia diagnosis. The PPV and NPV were 94 and 79 per cent, respectively. Reliance on the CT report alone underestimates the presence of incisional hernia. Referring physicians should not use CT as a screening modality for detection of hernias. Referral to a surgeon for evaluation before imaging may provide more accurate diagnosis and potentially decrease the cost of caring for this population.

Prevalence and Impact on Quality of Life of Occult Hernias among Patients Undergoing Computed Tomography

BACKGROUND

With the widespread use of advanced imaging there is a need to quantify the prevalence and impact of hernias. We aimed to determine the prevalence of abdominal wall hernias among patients undergoing computed tomography (CT) scans and their impact on abdominal wall quality of life (AW-QOL).

METHODS

Patients undergoing elective CT abdomen/pelvis scans were enrolled. Standardized physical examinations were performed by surgeons blinded to the CT scan results. AW-QOL was measured through the modified Activities Assessment Scale. On this scale, 1 is poor AW-QOL, 100 is perfect, and a change of 7 is the minimum clinically important difference. Three surgeons reviewed the CT scans for the presence of ventral or groin hernias. The number of patients and the median AW-QOL scores were determined for three groups: no hernia, hernias only seen on imaging (occult hernias), and clinically apparent hernias.

RESULTS

A total of 246 patients were enrolled. Physical examination detected 62 (25.2%) patients with a hernia while CT scan revealed 107 (43.5%) with occult hernias. The median (interquartile range) AW-QOL of patients per group was no hernia = 84 (46), occult hernia = 77 (57), and clinically apparent hernia = 62 (55).

CONCLUSIONS

One-fourth of individuals undergoing CT abdomen/pelvis scans have a clinical hernia, whereas nearly half have an occult hernia. Compared with individuals with no hernias, patients with clinically apparent or occult hernias have a lower AW-QOL (by 22 and seven points, respectively). Further studies are needed to determine natural history of AW-QOL and best treatment strategies for patients with occult hernias.

Urgent Multidetector Computed Tomography in Colon Cancer: Postsurgical Changes and Early Complications

Complications after surgery for colorectal cancer are common in emergency departments. Multidetector computed tomography plays a fundamental role in the follow-up of patients after surgery, because it enables the detection of relapse and complications. Radiologists need to be familiar with different surgical techniques and the normal postsurgical changes so that we can differentiate them from potential complications and relapse. This article reviews the multidetector computed tomography findings that can be considered normal after surgical intervention for colorectal cancer as well as the most common early complications seen in postsurgical colorectal cancer patients presenting at emergency departments.

Imaging of the Postoperative Colon

Recognition of postoperative complications is important for the immediate diagnosis and treatment needed for appropriate patient care. Identification of postoperative complications from colon surgery requires not only knowledge of the type of procedure, but also the expected normal postoperative appearance. The purpose of this article is to discuss and review the expected anatomic changes after colorectal surgery, and the appearance of the most common postoperative complications.

Systematic Review and Meta-Regression of Factors Affecting Midline Incisional Hernia Rates: Analysis of 14,618 Patients

BACKGROUND

The incidence of incisional hernias (IHs) following midline abdominal incisions is difficult to estimate. Furthermore recent analyses have reported inconsistent findings on the superiority of absorbable versus non-absorbable sutures.

OBJECTIVE

To estimate the mean IH rate following midline laparotomy from the published literature, to identify variables that predict IH rates and to analyse whether the type of suture (absorbable versus non-absorbable) affects IH rates.

METHODS

We undertook a systematic review according to PRISMA guidelines. We sought randomised trials and observational studies including patients undergoing midline incisions with standard suture closure. Papers describing two or more arms suitable for inclusion had data abstracted independently for each arm.

RESULTS

Fifty-six papers, describing 83 separate groups comprising 14,618 patients, met the inclusion criteria. The prevalence of IHs after midline incision was 12.8% (range: 0 to 35.6%) at a weighted mean of 23.7 months. The estimated risk of undergoing IH repair after midline laparotomy was 5.2%. Two meta-regression analyses (A and B) each identified seven characteristics associated with increased IH rate: one patient variable (higher age), two surgical variables (surgery for AAA and either surgery for obesity surgery (model A) or using an upper midline incision (model B)), two inclusion criteria (including patients with previous laparotomies and those with previous IHs), and two circumstantial variables (later year of publication and specifying an exact significance level). There was no significant difference in IH rate between absorbable and non-absorbable sutures either alone or in conjunction with either regression analysis.

CONCLUSIONS

The IH rate estimated by pooling the published literature is 12.8% after about two years. Seven factors account for the large variation in IH rates across groups. However there is no evidence that suture type has an intrinsic effect on IH rates.

Incarceration of the hepatic lobe in incisional hernia: A case report

Introduction

Incisional hernias are abnormal peritoneal outward pouch-like protrusions that develop due to defects that arise as a result of the disruption of the fascia's continuity after abdominal surgery.

Presentation of case

A 77-year-old female patient presented to the emergency department of our hospital with complaints of abdominal swelling, abdominal pain, nausea and vomiting. The patient was recommended for surgery. It was decided that the primary fascia closure and onlay patch was the most appropriate approach.

Discussion

When the defect in the abdominal wall grows, the functionality of the related abdominal wall is disrupted thereby eliminating the dynamic structure of the abdominal wall. Incisional hernias lead to a significant number of job losses and morbidity and negatively affect quality of life. Moreover, the formations in the hernia pouch might lead to higher risk of strangulation and dysfunction.

Conclusion

Subcutaneous herniation of the left lobe of the liver passing through the abdominal wall is a very rare condition.

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Incisional hernias are common type of hernia.

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Left liver lobe may be incarcerated into the hernia sac.

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Surgeon should be careful not to damage it.

Diagnostic value of automated 3D ultrasound for incisional hernia

The automated volume scanning system (AVSS) has been applied in breast diseases, but its use in incisional hernias has not been reported. In this study, conventional handheld B-mode ultrasound (HHUS) and AVSS examined a total of 122 hernia defects in 78 patients. The results from two modalities were then compared with surgical findings for the purpose of assessing the diagnostic value of AVSS. Statistics showed that surgeries identified 38 small, 23 medium and 17 large incisional hernias. The results of AVSS completely agreed with surgical findings; however, HHUS misidentified nine large hernias as medium and seven medium hernias as large. AVSS proved to be more accurate than HHUS in measuring the length and width of the hernia. It also outperformed HHUS in both detecting the incisional hernias (91.8% vs. 78.7%, p = 0.00) and determining hernia contents (89.3% vs. 68.0%, p = 0.00). Moreover, the coronal images AVSS obtained clearly displayed the shapes of the hernias, with 46 being regular and 32 irregular. Overall, AVSS can be used as a promising diagnostic modality for incisional hernias.

Incisional bladder hernia following appendectomy: report of a case

We herein report the case of a 68-year-old male who presented with a few years' history of swelling at the scar of an appendectomy, which he had undergone nearly 40 years earlier, and which was associated with radiating pain towards the penis when he pushed on the swelling. The scar was located in the right lower quadrant of the abdomen. Abdominal sonography and a computed tomography (CT) scan demonstrated the presence of an incisional bladder hernia, and surgery was performed. The herniated bladder was successfully replaced into the preperitoneal space, and the orifice was covered with a polypropylene mesh. Most bladder hernias develop in the inguinal and/or femoral region, and an incisional bladder hernia is extremely rare, especially after abdominal surgery. To our knowledge, this is the fourth report of an incisional bladder hernia following abdominal surgery.

Radiological incidence of parastomal herniation in cancer patients with permanent colostomy: what is the ideal size of the surgical aperture?

BACKGROUND

Parastomal herniation frequently complicates stoma formation. Aperture size has been shown to be an independent predictor of hernia development but there is a paucity of data regarding the ideal stoma diameter. The aim of this study was to establish the radiological incidence of herniation in patients with a permanent colostomy and correlate it with the size of the abdominal wall defect in order to identify an aperture diameter associated with a reduced herniation risk.

METHODS

All patients who underwent permanent colostomy formation for colorectal cancer over a five-year period in a single institution were recruited to the study. Patient demographics, operative details and stoma-related symptoms were recorded. Post-operative CT scans were reviewed for evidence of parastomal herniation. The diameter of the abdominal wall defect was measured radiologically.

RESULTS

43 patients (mean age 69 years) were included in the analysis. Radiologically, 25/43 (58%) had evidence of a parastomal hernia. The median aperture diameter was 35 mm (range 25-58 mm) in patients with a parastomal hernia and 22 mm (range 10-36 mm) in patients without herniation (p < 0.0001). There were no cases of herniation with an abdominal wall defect size <25 mm. The median follow up was 26.0 months (range 6-55) in patients with herniation as opposed to 16.0 months (range 7-36) in patients without herniation (p = 0.11).

CONCLUSION

The majority of patients with a permanent colostomy develop a parastomal hernia within the first two post-operative years. Parastomal herniation appears unlikely to develop with an abdominal wall defect diameter ≤25 mm provided this does not enlarge with time. Surgical techniques that utilise stapling devices to form a 'custom-made' and rigid trephine might reduce the herniation risk.

Comparative effectiveness of dynamic abdominal sonography for hernia vs computed tomography in the diagnosis of incisional hernia

BACKGROUND

Diagnosis and characterization of incisional hernia are often established by CT, which incurs radiation exposure and substantial cost in clinical practice. The purpose of this study was to determine the comparative effectiveness of surgeon-performed Dynamic Abdominal Sonography for Hernia (DASH) vs CT for incisional hernia evaluation.

STUDY DESIGN

Patients with previous abdominal operations and recent CT imaging were enrolled prospectively; patients with stomas, fistula, or soft tissue infection were excluded. In the clinic setting, DASH was performed with prerequisite training of the American College of Surgeons Ultrasound for Surgeons Basic Course. Clinical evidence of hernia, results of DASH examination, and radiologist documentation of incisional hernia were compared with the gold standard of surgeon-interpreted CT. Testing characteristics of sensitivity and specificity were compared and predictive values were calculated. Inter-rater reliability was performed by comparing DASH results in a subgroup of patients with 3 different evaluators.

RESULTS

There were 181 patients enrolled, with a mean age of 54 years, and 68% were women. In patients in whom hernias were identified, the mean hernia size was 44.6 cm(2) (range 0.2 to 468.3 cm(2)). The DASH examination showed high sensitivity (98%) and specificity (88%). Hernia prevalence was 55% in this population, resulting in positive and negative predictive values of 91% and 97%, respectively. Four patients had clinically detectable hernias that were not seen on CT but were discovered with DASH. Inter-rater reliability for DASH was high, with an observed intraclass correlation coefficient of 0.79.

CONCLUSIONS

The DASH examination is an accurate alternative to CT scan for diagnosing abdominal wall hernias, with additional benefits of no radiation exposure and instant bedside interpretation. The use of DASH to detect hernia recurrence can greatly facilitate long-term follow-up of hernia patients.

Abdominal hernias: Radiological features

Abdominal wall hernias are common diseases of the abdomen with a global incidence approximately 4%-5%. They are distinguished in external, diaphragmatic and internal hernias on the basis of their localisation. Groin hernias are the most common with a prevalence of 75%, followed by femoral (15%) and umbilical (8%). There is a higher prevalence in males (M:F, 8:1). Diagnosis is usually made on physical examination. However, clinical diagnosis may be difficult, especially in patients with obesity, pain or abdominal wall scarring. In these cases, abdominal imaging may be the first clue to the correct diagnosis and to confirm suspected complications. Different imaging modalities are used: conventional radiographs or barium studies, ultrasonography and Computed Tomography. Imaging modalities can aid in the differential diagnosis of palpable abdominal wall masses and can help to define hernial contents such as fatty tissue, bowel, other organs or fluid. This work focuses on the main radiological findings of abdominal herniations.

The prevalence of parastomal hernia after formation of an end colostomy. A new clinico-radiological classification

INTRODUCTION

Parastomal hernia (PH) is a common complication of end colostomy, found in over 50% of patients. Abdominal computerized tomography (CT) may help diagnosis. The prevalence of PH may be higher than previously reported. We present a new CT classification for use in clinical practice.

METHOD

A cross-sectional, descriptive observational study was carried out, assessing the clinical and radiological prevalence of PH in 75 patients with an end colostomy operated on since 1997. Clinical examinations were performed by a single surgeon. Abdominal CTs were assessed by a single radiologist.

RESULTS

PH was observed clinically in 33 (44%) of 75 patients and 27 (82%) were symptomatic. Using the classification 0 (Normal), I (Hernial sac containing stoma loop), II (Sac containing omentum), III (Sac containing a loop other than stoma), radiological PH was observed in 35 (47%) patients. Clinical/radiological concordance (Kappa index = 0.4) increased proportionally with sac size. All type-III PHs (n = 9) were symptomatic. The combined prevalence of PH detected by one or other method was 60.8%.

CONCLUSION

Clinical and radiological prevalence of PH is high. As there is no gold standard for PH detection, we recommend a combination of the two methods. A new classification for use in clinical practice is proposed.

Abdominal Hernias: Imaging Review and Historical Perspectives

Many eminent anatomists originally described abdominal hernias, some of which are still named after the original authors. In this article, the radiologic features of abdominal hernias are reviewed as imaged on x-ray, ultrasound, multidetector computed tomography, and magnetic resonance imaging. Recognition of the typical appearance of various types of abdominal hernias and associated adverse features such as bowel obstruction, perforation, strangulation, or volvulus formation can help in formulating an accurate diagnosis. A short biography of the scientists associated with eponymous hernias and their other important scientific contributions are also described.

Abdominal Wall Hernias: Imaging Features, Complications, and Diagnostic Pitfalls at Multi–Detector Row CT

Abdominal wall hernias are a common imaging finding in the abdomen and may be complicated by strangulation, incarceration, or trauma. Because of the risk of developing complications, most abdominal wall hernias are surgically repaired, even if asymptomatic. However, post-surgical complications are also common and include hernia recurrence, infected and noninfected fluid collections, and complications related to prosthetic material. Multi-detector row computed tomography (CT) with its multiplanar capabilities is particularly useful for the evaluation of unrepaired and surgically repaired abdominal wall hernias. Multi-detector row CT provides exquisite anatomic detail of the abdominal wall, thereby allowing accurate identification of wall hernias and their contents, differentiation of hernias from other abdominal masses (tumors, hematomas, abscesses), and detection of pre- or postoperative complications. These findings improve the communication of imaging results to clinicians and help optimize treatment planning. Knowledge of multi-detector row CT findings in unrepaired and surgically repaired abdominal wall hernias and their complications is essential for making the correct diagnosis and may help guide clinical management.

MDCT of Abdominal Wall Hernias: Is There a Role for Valsalva's Maneuver?

OBJECTIVE

Our objective was to evaluate the role of Valsalva's maneuver during MDCT for the diagnosis and characterization of abdominal wall hernias.

SUBJECTS AND METHODS

From September 2002 to May 2003, 100 consecutive patients (37 men and 63 women; mean age, 53 years) with suspected anterior abdominal wall hernias underwent 4-, 8-, or 16-MDCT with and without Valsalva's maneuver. Patients received both oral and IV contrast material. On a workstation, three independent reviewers evaluated each scan obtained during rest and during Valsalva's maneuver for the following parameters: anteroposterior (AP) diameter of the abdomen; presence, location, and contents of the hernia; and transverse diameter of the fascial defect. The scans were compared to assess for changes in hernia size and contents and to determine whether the hernia would have been overlooked without Valsalva's maneuver. Fisher's exact test, the McNemar test, and Cohen's kappa coefficient were used to assess for significant differences.

RESULTS

The three reviewers identified a mean of 72 abdominal wall hernias (72%). The reviewers agreed (kappa = 0.723) with respect to the presence of a hernia. AP diameters increased an average of 1.33 cm during Valsalva's maneuver (p < 0.001). The transverse diameter of the fascial defect increased an average of 0.66 cm and the AP diameter of the hernia sac increased an average of 0.79 cm during Valsalva's maneuver (p < 0.001). Fifty percent of the hernias became more apparent with Valsalva's maneuver. Ten percent of the hernias could be detected only on the scan obtained during Valsalva's maneuver. Conversely, in no patients was the hernia detected only on the rest scan.

CONCLUSION

As opposed to scans obtained at rest, scans obtained during Valsalva's maneuver aid in the detection and characterization of suspected abdominal wall hernias. A single scan obtained during Valsalva's maneuver is sufficient to detect 100% of anterior abdominal wall hernias identified on CT.

Inguinal hernias: MRI and ultrasound

This article presents an overview of the key anatomic structures of the groin region as seen on gross anatomy and the appearance of these structures on ultrasound and magnetic resonance imaging (MRI). An overview of the sonographic and MRI techniques used in preoperative diagnosis of inguinal hernias is provided, and their value is discussed. Finally, the role of ultrasound and MRI after surgical inguinal hernia repair is addressed.

Abdominal wall hernias: cross-sectional imaging signs of incarceration determined with sonography

OBJECTIVE

The aim of this study was to determine with sonography whether distinct cross-sectional imaging signs exist that may differentiate between incarcerated and nonincarcerated abdominal wall hernias.

SUBJECTS AND METHODS

The sonographic appearance of 149 consecutive abdominal wall hernias was prospectively investigated and correlated with subsequent surgical results. Commercially available 4- to 10-MHz linear transducers and 2- to 5-MHz curved transducers were used to evaluate the hernias.

RESULTS

Surgery revealed 126 nonincarcerated and 23 incarcerated hernias. The sonographic signs suggestive of incarceration that we identified included free fluid in the hernia sac, which was observed in 91% of the incarcerated hernias and in 3% of the nonincarcerated hernias; bowel wall thickening in the hernia, which was detected in 88% of the incarcerated hernias and in none of the nonincarcerated hernias; fluid in the herniated bowel loop, which was detected in 82% of the incarcerated hernias and in 3% of the nonincarcerated hernias; and dilated bowel loops in the abdomen, which occurred in 65% of the incarcerated hernias and in none of the nonincarcerated hernias. These imaging findings allowed the identification of incarceration in all 23 cases and led to a false-positive result in two of 126 nonincarcerated hernias.

CONCLUSION

Cross-sectional imaging signs indicating hernial incarceration included free fluid in the hernial sac, bowel wall thickening in the hernia, fluid in the herniated bowel loop, and dilated bowel loops in the abdomen. Sonography is an appropriate cross-sectional imaging modality for detecting these signs that are helpful in diagnosing patients with atypical clinical presentations.

Bowel obstruction following liver transplantation: clinical and ct findings in 48 cases with emphasis on internal hernia

PURPOSE

To review the incidence, cause, and radiologic findings of bowel obstruction in patients who have undergone orthotopic liver transplantation (OLT).

MATERIALS AND METHODS

Retrospective review of 4,001 cases of OLT revealed 48 cases of bowel obstruction in 44 patients. Seventeen computed tomographic (CT) scans and seven barium-enhanced radiographs were reviewed to determine level and cause. Surgical proof was available in 45 cases, while three had characteristic clinical and radiographic features.

RESULTS

Adhesions caused the obstruction in 19 cases in 16 patients; three had bowel ischemia. Internal hernias caused obstruction in 18 patients; all obstructions were transmesenteric or retroanastomotic and occurred with choledochoenteric anastomosis. Seven patients had volvulus; four had bowel ischemia. CT signs of internal hernia included mesenteric vascular abnormalities and clusters of dilated small-bowel segments that displaced the colon away from the abdominal wall. Prospective diagnosis of internal hernia was made in only one case. Incisional or inguinal hernia caused obstruction in seven patients; CT was used just once. Four patients had neoplastic bowel obstruction, three due to posttransplantation lymphoproliferative disorder and one due to colon carcinoma.

CONCLUSION

Liver transplantation was complicated by bowel obstruction in 48 (1.2%) of 4,001 cases. While adhesions and incisional hernias are common and well recognized, other causes are more challenging to diagnose. The CT findings reported here may allow more accurate diagnosis of internal hernia.

Abdominal wall hernias: imaging with spiral CT

Computed tomography is an accurate method of identifying the various types of abdominal wall hernias, especially if they are clinically occult, and of distinguishing them from other diseases such as hematomas, abscesses and neoplasia. In this study we examined the CT images of 94 patients affected by abdominal wall hernias observed over a period of 6 years. Computed tomography clearly demonstrates the anatomical site of the hernial sac, the content and any occlusive bowel complications due to incarceration or strangulation. Clinical diagnosis of external hernias is particularly difficult in obese patients or in those with laparotic scars. In these cases abdominal imaging is essential for a correct preoperative diagnosis and to determine the most effective treatment.

Abdominal wall hernias: imaging with spiral CT

Computed tomography is an accurate method of identifying the various types of abdominal wall hernias, especially if they are clinically occult, and of distinguishing them from other diseases such as hematomas, abscesses and neoplasia. In this study we examined the CT images of 94 patients affected by abdominal wall hernias observed over a period of 6 years. Computed tomography clearly demonstrates the anatomical site of the hernial sac, the content and any occlusive bowel complications due to incarceration or strangulation. Clinical diagnosis of external hernias is particularly difficult in obese patients or in those with laparotic scars. In these cases abdominal imaging is essential for a correct preoperative diagnosis and to determine the most effective treatment.

Dynamic magnetic resonance imaging in the diagnosis of groin hernia

RATIONALE AND OBJECTIVES

The authors determine the feasibility of dynamic magnetic resonance (MR) imaging in the diagnosis of groin hernia.

METHODS

Ten volunteers and 10 patients with clinically evident and surgically proven herniations were evaluated using T1-, and T2-weighted sequences and two dynamic sequences. The visibility of anatomic structures that are crucial for the assessment and the differentiation of inguinofemoral herniations was evaluated.

RESULTS

The inguinal rings could be identified in all subjects. The inferior epigastric vessels could be identified in 85%. In 10 patients, 11 hernias were found at MR imaging, whereas at surgery and physical examination 13 herniations were diagnosed (84.6%). The two hernias that were missed initially could be identified retrospectively on MR imaging. One volunteer showed a small bilateral inguinal hernia on MR imaging that could be confirmed on physical examination.

CONCLUSIONS

The anatomic structures that are crucial for the assessment and the differentiation of inguinofemoral herniations can be identified prospectively with MR imaging.

Paraileostomy hernia: a clinical and radiological study

Forty-six patients who underwent colectomy with end ileostomy for ulcerative colitis (n = 33) or Crohn's disease (n = 13) have been reviewed for paraileostomy hernia (PIH) formation 1-16 years after surgery. PIH developed in 13 of these patients (28 per cent) and was not related to the original disease or excessive weight gain. Twenty-eight patients underwent limited computed tomography (CT) scanning of the stomal region. Eight of these had a clinically detectable PIH, which was demonstrated on CT. A further two patients had PIH demonstrated on CT which was not detected by clinical examination. The rate of PIH was similar where the stoma emerged lateral to the rectus abdominis muscle (six out of 16 patients, 37 per cent) to where the stoma emerged through the rectus (four out of 12 patients, 33 per cent). Recurrence following operative repair of PIH was common. PIH occurs more frequently than previously supposed. CT can detect PIH and may be useful in evaluating a patient with stoma-related symptoms for occult PIH formation.

Demonstration of para-ileostomy herniation using computed tomography

Twenty-eight patients with end ileostomies underwent localised computed tomography (CT) of the ileostomy region. Para-ileostomy herniation was demonstrated in 10 patients. In two of these the hernia was not detectable clinically. This incidence (36%) is higher than that reported previously. Herniation was associated with a larger defect in the anterior abdominal wall at the stomal site and was more common lateral to the stoma. No association was shown between herniation and the underlying disease process, or to the site of the stoma relative to the rectus abdominis muscle. Demonstration of a hernia by clinical examination or CT was important in clinical management decisions. CT is recommended in patients with stoma-related symptoms or unexplained abdominal symptoms following ileostomy formation when a para-stomal hernia is suspected, but clinical examination is negative.