CT diagnosis of the nature of bowel obstruction: morphological evaluation of the transition point

A diagnostic dilemma: Pedunculated mesenteric lipodystrophy mimicking Meckel’s diverticulum. A case report and literature review

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Mesenteric lipodystrophy is a rare fibroinflammatory disease of unknown origin.

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The detection of mesenteric lipodystrophy is challenging and requires early clinical suspicion.

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Clinical and imaging findings can mimick other pathological conditions affecting the mesenteric fat tissue.

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Contrast enhanced CT is the most accurate imaging technique for diagnosing mesenteric lipodystrophy.

Introduction

Mesenteric lipodystrophy is a rare fibroinflammatory disease of unknown origin with clinical and radiological non specific findings.

Presentation of the case

The case of a 42-years-old man affected by a pedunculated mesenteric lipodystrophy mimicking Meckel’s diverticulum is reported. Clinical, imaging and histological findings are discussed.

Discussion

Mesenteric lipodystrophy affects the mesenteric fat of the abdomen with a typical diffuse thickening of the mesentery, nodular thickening of the mesenteric root and presence of mass-like lesions. Ultrasound (US) and Multiphasic Computed Tomography (CT) represent the main imaging tools used for diagnosis. Clinical and imaging findings can mimick other pathological conditions affecting the mesenteric fat tissue. Contrast enhanced CT is the most accurate imaging technique for diagnosing mesenteric lipodystrophy due to the high panoramicity and accuracy with multiplanar imaging. Multiphasic technique helps to characterize the lesion and to recognize vascular anatomy. Oral administration of iodinated contrast medium may help to assess the relationship with bowel loops. All these diagnostic elements are crucial for the surgical timing and approach.

Conclusions

Due to the heterogeneous mesenteric involvement, the nonspecific CT findings and the high number of diseases for differential diagnosis, the detection of mesenteric lipodystrophy is challenging and requires early clinical suspicion. An histological examination is always necessary.

Lipoma of the transverse colon covered by tubulovillous adenoma: a rare indication for surgical treatment

Lipomas of the digestive tract are rare benign tumours which, in most cases, are totally asymptomatic. Because of their localization within the intestinal wall, endoscopy may be completely negative so contrast-enhanced computed tomography (CT) is very important for detecting and typing these lesions. The case of a 49-year-old man with abdominal pain is presented. Colonoscopy and biopsy of a polypoid lesion on the right colonic flexure concluded for tubulovillous adenoma. The subsequent CT showed a polylobate lesion of 5 cm in diameter with predominant fat density causing luminal sub-stenosis. Histological examination of the surgical specimen confirmed the presence of a voluminous submucosal lipoma. CT allows to diagnose lipomas of the large bowel thanks to the density measurement (between -40 and -120 Hunsfield Units) with an accurate detection of the site and nature of lumen stenosis.

Reversible pneumatosis cystoides intestinalis after liver transplantation

Pneumatosis cystoides intestinalis (PCI) is a rare disease characterized by the presence of multiple gas-filled cysts within the submucosa or subserosa of the intestinal wall. We report a case of PCI in a 54-yearold man 4 weeks after liver transplantation due to hepatitis B virus (HBV)-associated liver cirrhosis presenting with illness, diarrhea and abdominal pain. CT scans revealed normal shape of the abdominal parenchymal organs and no intra-hepatic complication due to liver transplantation. Main abdominal venous and arterial vessels resulted patent. Colic loops appeared diffusely thickened for the presence of variable diameter air-filled cysts located within the bowel wall. The patient underwent conservative treatment and the CT control after 4 weeks showed a complete PCI resolution. PCI after adult liver transplantation is probably due to the pre-transplantation chemotherapy, immunosuppressive therapy and opportunistic enteric infections. Abdominal CT represents the gold standard technique for diagnosing PCI and for evaluating its extension and complications providing data on other abdominal pathologies. It appears as variable diameter gas-filled cysts located within the bowel wall and it is often associated with pneumo-peritoneum probably due to the rupture of subserosal cysts. PCI has a favorable outcome and requires conservative treatment. Major differential diagnosis includes intestinal pneumatosis due to bowel ischemia. PCI after liver transplantation represents an uncommon bowel disease with a favorable prognosis. CT represents the reference imaging technique for diagnosing the disease and evaluating the response to therapy which is usually conservative rather than surgical.

Comparison between CT Net enhancement and PET/CT SUV for N staging of gastric cancer: A case series

BACKGROUND

The therapeutic approach of gastric cancer strictly depends on TNM staging mainly provided by CT and PET/CT. However, the lymph node size criterion as detected by MDCT causes a poor differential diagnosis between reactive and metastatic enlarged lymph nodes with low specificity values. Our study aims to compare 320-row CT Net enhancement and fluorine-18 fluoro-2-deoxy-d-glucose positron emission tomography/computed tomography (F-FDG PET/CT) SUV for N staging of gastric cancer.

MATERIALS AND METHODS

45 patients with histologically proven gastric cancer underwent CT and F-FDG PET/CT. Two radiologists in consensus evaluated all images and calculated the CT Net enhancement and F-FDG PET/CT SUV for N staging, having the histological findings as the reference standard. CT and F-FDG PET/CT sensitivity, specificity, diagnostic accuracy, positive and negative predictive values (PPV and NPV) were evaluated and compared by using the Mc Nemar test.

RESULTS

The histological examination revealed nodal metastases in 29/45 cases (64%). CT Net enhancement obtained sensitivity, specificity, accuracy, PPV and NPV of 90%, 81%, 87%, 90% and 81%, respectively. F-FDG PET/CT SUV obtained sensitivity, specificity, accuracy, PPV and NPV of 66%, 88%, 73%, 90% and 58%, respectively. No statistically significant difference between the two imaging modalities was found (p = 0.1).

CONCLUSION

CT Net enhancement represents an accurate tool for N staging of gastric cancer and could be considered as the CT corresponding quantitative parameter of F-FDG PET/CT SUV. It could be applied in the clinical practice for differentiating reactive lymph nodes from metastatic ones improving accuracy and specificity of CT.

Early MRI findings of small bowel obstruction: an experimental study in rats

PURPOSE

This study was undertaken to identify the early magnetic resonance imaging (MRI) findings of small bowel obstruction (SBO) and to analyse their evolution over time comparing them with histological findings.

MATERIALS AND METHODS

SBO was surgically induced in 10 rats divided into two groups monitored at predetermined time points until the 8th hour: group 1, macroscopically observed and group 2, investigated with 7-Tesla micro-MRI (7 T μ-MR). At the end of observation, the bowel was excised for histological analysis.

RESULTS

7 T μ-MRI T2-w sequences acquired 15 min after SBO, showed early evidence of bowel wall hyperintensity and a small amount of peritoneal free fluid. At 1 h, a hyperintensity of the loop proximal to the obstruction was found and, after 4 h, free fluid between the loops, bowel wall thickening and increased wall hyperintensity were also found. After 6 h hypotonic reflex ileus (only gas-filled dilated loops) was detected, which became paralytic ileus (dilation with air-fluid levels) after 8 h. The MRI findings were all confirmed at histological examination.

CONCLUSIONS

This study allows definition of the early MRI features of SBO (peritoneal free fluid and hyperintensity of the injured bowel) and their chronological evolution, also confirmed by histological examination. Our data suggest a potential role of MR imaging in the early diagnostic assessment and management of patients with SBO. The chance to achieve an early detection of bowel injury and to correlate the histological pattern with imaging findings could contribute to a finer and earlier diagnosis and a more effective treatment.

Accuracy of ultrasonography in the diagnosis of acute appendicitis in adult patients: review of the literature

Background

Ultrasound is a widely used technique in the diagnosis of acute appendicitis; nevertheless, its utilization still remains controversial.

Methods

The accuracy of the Ultrasound technique in the diagnosis of acute appendicitis in the adult patient, as shown in the literature, was searched for.

Results

The gold standard for the diagnosis of appendicitis still remains pathologic confirmation after appendectomy. In the published literature, graded-compression Ultrasound has shown an extremely variable diagnostic accuracy in the diagnosis of acute appendicitis (sensitivity range from 44% to 100%; specificity range from 47% to 99% ). This is due to many reasons, including lack of operator skill, increased bowel gas content, obesity, anatomic variants, and limitations to explore patients with previuos laparotomies.

Conclusions

Graded-compression Ultrasound still remains our first-line method in patients referred with clinically suspected acute appendicitis: nevertheless, due to variable diagnostic accuracy, individual skill is requested not only to perform a successful exam, but also in order to triage those equivocal cases that, subsequently, will have to undergo assessment by means of Computed Tomography.

Ultrasonography (US) in the assessment of pediatric non traumatic gastrointestinal emergencies

Background

Non traumatic gastrointestinal emergencies in the children and neonatal patient is a dilemma for the radiologist in the emergencies room and they presenting characteristics ultrasound features on the longitudinal and axial axis. The most frequent emergencies are : appendicitis, intussusceptions, hypertrophic pyloric stenosis, volvulus due to intestinal malrotation. The aim of this article is to familiarize the reader with the US features.

Methods

A retrospective analysis of 200 ultrasound examinations performed in neonatal and children patients with fever, abdominal pain, leukocytosis, vomiting and diarrhea were evaluated.

Results

Of 200 exame 50 cases of intussusceptions, 100 cases of appendicitis, 20 cases associated with abscess;10 gangrenous appendicitis with absence a color Doppler , and 10 cases of perforated appendicitis at tomography computer integration and 10 cases of volvulus was found.

Conclusions

Ultrasonography (US) is therefore rapidly becoming an important imaging modality for the evaluation of acute abdominal pain, particularly in pediatric patients, where satisfactory examination is often not achievable for the attending clinicians. US provides excellent anatomic detail on the longitudinally and axial axis .

Management of bowel obstruction in patients with stage IV cancer: predictors of outcome after surgery

BACKGROUND

Patients with stage IV cancer and bowel obstruction (BO) present a complicated management problem. We sought to determine if specific parameters could predict outcome after surgery.

METHODS

Records of patients with stage IV cancer and BO treated from 1991 to 2008 were reviewed. For surgical patients, 30-day morbidity and 90-day mortality were assessed using exact multivariable logistic regression methods.

RESULTS

Of 198 patients, 132 (66.7%) underwent surgery, 66 medical treatment alone, and demographics were similar. A total of 41 patients (20.7%) were diagnosed with stage IV cancer and BO synchronously, all treated surgically; the remaining presented metachronously. Medically managed patients were more likely to have received chemotherapy in the 30 days prior to BO (45 of 66 [68.2%] vs 40 of 132 [30.3%], p < .01). In the surgical group, 30-day morbidity was 35.6%, while 90-day mortality was 42.3%. Median overall survival for synchronous patients was 14.1 months (95% confidence interval [95% CI] 7.6-23.2), and 3.7 months (95% CI 2.5-5.2) and 3.6 months (95% CI 1.5-5.2) for metachronous patients treated surgically and medically, respectively. A multivariate model for 90-day surgical mortality identified low serum albumin, metachronous presentation, and ECOG > 1 as predictors of death (p < .05). A model for 30-day surgical morbidity yielded low hematocrit as a predictive factor (p < .05).

CONCLUSIONS

This cohort identifies characteristics indicative of morbidity and mortality in stage IV cancer and BO. Low serum albumin, ECOG > 1, and metachronous presentation predicted for 90-day surgical mortality. These data suggest factors that can be used to frame treatment discussion plans with patients.