De-misty-fying the mesentery: an algorithmic approach to neoplastic and non-neoplastic mesenteric abnormalities

Unravelling the Mysteries of the Mesentery

The mesentery and its folds tether the small bowel loops to the posterior abdominal wall. It transmits nerves, vessels, and lymph ensconced in a fatty sponge layer wrapped in a thin glistening peritoneum, from and to the small bowel. Not only does this flexible dynamic fatty apron house various localized primary benign and malignant lesions, it is often involved in and gives an indication of generalized or systemic diseases in the body. An understanding of the anatomy, components, and function of the mesentery helps to classify mesenteric abnormalities. This further allows for characterizing radiological patterns and appearances specific to certain disease entities. Recent reviews of mesenteric anatomy have kindled new interest in its function and clinical applications, heralding the possibility of revision of its role in diseases of the abdomen.

Relationship of mesenteric panniculitis with visceral and subcutaneous adipose tissue

Background/aim

Mesenteric panniculitis (MP) is an idiopathic benign disease characterized by fat necrosis, chronic inflammation, and fibrosis. The relationship between obesity and chronic low-grade inflammation has been reported. This study investigated the relationship of MP diagnosed using multidetector computed tomography (MDCT) with visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) areas.

Materials and methods

We retrospectively enrolled 104 patients with no radiological findings other than MP. Additionally, 76 individuals without any indicative radiological findings were included as controls. VAT and SAT were separately calculated (cm2) using a 3-dimensional workstation. The abdominal circumference was measured (cm).

Results

The mean abdominal circumference was 99.9 ± 7.9 cm, SAT was 195.3 ± 89.1 cm2, and VAT was 203.9 ± 72.8 cm2 in the MP group. The abdominal circumference, VAT, and SAT were significantly higher in the MP group than in the control group (P < 0.001). According to the receiver operating characteristic (ROC) analysis, cut-off level VAT and SAT were 167.5 cm2 (sensitivity 71%, specificity 69%) and 117.5 cm2 (sensitivity 78%, specificity 51 %), respectively.

Conclusion

Increased VAT and SAT were associated with MP, suggesting their role in the etiology of MP.

Demystifying the mesenteric root lesions

OBJECTIVE

The aim of this article is to describe the normal anatomy of the root of the small bowel mesentery (RSBM) as well as the multidetector computed tomography (MDCT) features of the various primary and secondary lesions that affect the RSBM.

RESULTS

The small bowel mesentery attaches the jejunum and ileum to the posterior abdominal wall, the line of attachment forming the RSBM. Several primary as well as secondary lesions involve the RSBM. The RSBM has anatomical contiguity with the mesocolon and other peritoneal ligaments, which forms a route for the spread of infection, neoplasms as well as several other abdominal pathologies. MDCT plays an important role in the evaluation of mesenteric root lesions.

CONCLUSION

Familiarity with the lesions involving the RSBM and their characteristic appearances on MDCT is important in giving thoughtful differential diagnosis and guiding the treating physician in further management.

[Incidental findings of the kidneys, adrenal glands, adnexa uteri, gastrointestinal tract, mesentery and lymph nodes : Assessment and management recommendations]

CLINICAL ISSUE

Besides the upper abdominal parenchymal organs, the increasing application of cross-sectional imaging has also led to a rising number of incidental findings in the kidneys, adrenal glands, adnexa uteri, the gastrointestinal tract, mesentery and abdominal lymph nodes.

STANDARD RADIOLOGICAL METHODS

Abdominal computed tomography investigations often show unexpected findings without any correlating symptoms. The growing clinical relevance is due to the large number of incidental findings as well as an increasing awareness of ethical and socioeconomic factors.

ACHIEVEMENTS

When interpreting radiological findings not only morphological criteria but also individual risk factors of the patient and the clinical context are of great importance.

PRACTICAL RECOMMENDATIONS

The aims of this article are the description and evaluation of frequent incidental findings detected by computed tomography and to provide information about management recommendations.

The Prevalence of Incidentally Detected Idiopathic Misty Mesentery on Multidetector Computed Tomography: Can Obesity Be the Triggering Cause?

PURPOSE

Misty mesentery appearance is commonly reported in daily practice, usually as a secondary finding of various pathological entities, but sometimes it is encountered as an isolated finding that cannot be attributed to any other disease entity. We aimed to assess the prevalence of cases with incidentally detected idiopathic misty mesentery on computed tomography (CT) and to summarize the pathologies leading to this appearance.

METHODS

Medical records and initial and follow-up CT features of patients with misty mesentery appearance between January 2011 and January 2013 were analysed. The study included cases with no known cause of misty mesentery according to associated CT findings, clinical history, or biochemical manifestations, and excluded patients with diseases known to cause misty mesentery, lymph nodes greater than a short-axis diameter of 5 mm, discrete mesenteric masses, or bowel wall thickening.

RESULTS

There were a total of 561 patients in whom misty mesentery appearance was depicted on abdominopelvic CT scans. A total of 80 cases were found to have isolated incidental idiopathic misty mesentery, giving a prevalence of 7%. The common indication for CT examination was abdominal pain. There was a slight female predominance (51.3%). 67.5% of all patients were classified as obese and 17.5% as overweight.

CONCLUSIONS

The results of the present study show that idiopathic incidental misty mesentery appearance has a significant prevalence. Also, the high body mass index of these patients and the growing evidence of obesity-induced inflammatory changes in adipose tissue are suggestive of an association between obesity and misty mesentery appearance on CT.

Intraperitoneal tuberculous abscess: Computed tomography features

AIM: To evaluate the computed tomography (CT) features of intraperitoneal tuberculous abscess (IPTA).

METHODS: Eight patients with IPTA confirmed by pathology were analyzed retrospectively. The clinical symptoms, medical images, and surgical findings were evaluated. Involvement of the intestine, peritoneum, viscera, and lymph nodes was also assessed.

RESULTS: All 8 patients had a history of abdominal discomfort for 1 to 6 mo. Physical examination revealed a palpable abdominal mass in 6 patients. Three patients had no evidence of pulmonary tuberculosis (TB). All IPTAs (11 abscesses) were seen as a multiseptated, peripherally enhanced, hypodense mass with enlarged, rim-enhanced lymph nodes. The largest abscess diameter ranged from 4.5 cm to 12.2 cm. CT showed 2 types of IPTA: Lymph node fusion and encapsulation. Of the 8 patients, one had liver tuberculosis and one had splenic and ovarian tuberculosis. Two cases showed involvement of the terminal ileum and ileocecal junction. Ascites were found in 4 cases. Three patients had peritonitis and mesenteritis. Three patients showed involvement of the omentum. Three patients had histological evidence of caseating granuloma, and 5 had histological evidence of acid-fast bacilli.

CONCLUSION: CT is crucial in the detection and characterization of IPTA. Certain CT findings are necessary for correct diagnosis.