A. Lemos

Limits of normality of quantitative thoracic CT analysis

IntroductionAlthough computed tomography (CT) is widely used to investigate different pathologies, quantitative data from normal populations are scarce. Reference values may be useful to estimate the anatomical or physiological changes induced by various diseases.MethodsWe analyzed 100 helical CT scans taken for clinical purposes and referred as nonpathological by the radiologist. Profiles were manually outlined on each CT scan slice and each voxel was classified according to its gas/tissue ratio. For regional analysis, the lungs were divided into 10 sterno-vertebral levels.ResultsWe studied 53 males and 47 females (age 64 ± 13 years); males had a greater total lung volume, lung gas volume and lung tissue. Noninflated tissue averaged 7 ± 4% of the total lung weight, poorly inflated tissue averaged 18 ± 3%, normally inflated tissue averaged 65 ± 8% and overinflated tissue averaged 11 ± 7%. We found a significant correlation between lung weight and subjects height (P <0.0001, r2 = 0.49); the total lung capacity in a supine position was 4,066 ± 1,190 ml, ~1,800 ml less than the predicted total lung capacity in a sitting position. Superimposed pressure averaged 2.6 ± 0.5 cmH2O.ConclusionSubjects without lung disease present significant amounts of poorly inflated and overinflated tissue. Normal lung weight can be predicted from patients height with reasonable confidence.

Synchronous adenocarcinoma and carcinoid tumor of the terminal ileum in a Crohn's disease patient

BackgroundSeveral malignancies have been described in association with inflammatory bowel diseases, the most common being adenocarcinoma. Carcinoid tumor and Crohn disease has also been previously reported, however the coexistence of both neoplasms is quite rare and the clinical diagnosis is very difficult. Here we report what we believe to be the fourth case of a mixed adenocarcinoid tumor coexisting with Crohns disease.Case reportThe patient presented with clinical and radiological features of intestinal obstruction. Laparotomy showed a stricturing lesion in the last 6 cm of the terminal ileum with proximal dilation. Only the histology of the resected surgical specimen proved the presence of a mixed adenocarcinoid tumor involving the terminal ileum.ConclusionCarcinoid tumor should be suspected in elderly patients with Crohns disease presenting with intestinal obstruction and laparotomy should be considered to exclude malignancy.

Can the unenhanced phase be eliminated from dual-phase CT angiography for chest pain? Implications for diagnostic accuracy in acute aortic intramural hematoma.

OBJECTIVE The purposes of this study were to retrospectively assess the frequency of acute aortic intramural hematoma and evaluate whether the elimination of the unenhanced imaging acquisition series from the dual-phase MDCT angiography (CTA) protocol for chest pain might affect diagnostic accuracy in detecting intramural hematoma and justify the reduced radiation dose. MATERIALS AND METHODS From October 2006 to November 2012, 306 patients (mean age, 65.0 years) with acute chest pain underwent emergency CTA with a 64-MDCT scanner. Two experienced cardiovascular radiologists, blinded to the diagnosis, assessed the images in two different sessions in which enhanced (single-phase CTA) and combined unenhanced and contrast-enhanced (dual-phase CTA) findings were evaluated. Sensitivity, specificity, and accuracy along with 95% CIs were calculated. Surgical and pathologic diagnoses, including findings at clinical follow-up and any subsequent imaging modality, were used as reference standards. RESULTS Thirty-six patients were suspected of having intramural hematoma; 16 patients underwent both surgery and transesophageal echocardiography (TEE), and the remaining 20 underwent TEE. Single-phase CTA showed a higher number of false-negative and false-positive results than dual-phase CTA. With intramural hematoma frequency of 12% (95% CI, 8.38-15.91%), sensitivity, specificity, and accuracy were 94.4% (81.3-99.3%), 99.3% (97.4-99.9%), and 98.7% (96.7-99.6%) for combined dual-phase CTA and 68.4% (51.4-82.5%), 96.3% (93.2-98.2%), and 92.8% (89.3-95.4%) for single-phase CTA. Dual-phase was significantly better than single-phase CTA with respect to sensitivity (p=0.002), specificity (p=0.008), overall accuracy (p<0.001), and interrater agreement (p=0.001). CONCLUSION The frequency of acute aortic intramural hematoma is similar to that previously reported. The acquisition of unenhanced images during the chest pain dual-phase CTA protocol significantly improves diagnostic accuracy over single-phase CTA.

Single-versus multidetector-row CT: comparison of sedation rates, conventional angiograms and motion artefacts in young children following liver transplantation

Purpose.The aim of this study was to determine whether the use of multidetector computed tomography (MDCT) is associated with decreased sedation, frequency of motion artefacts and conventional angiograms compared with single-detector CT (SDCT).Materials and methods.CT examinations performed in young children between January 1993 and June 2005 were reviewed retrospectively. Prior to September 2000, SDCT was used; after that period, MDCT was used. The examinations obtained during these two periods were compared for the frequency of sedation, motion artefacts, and conventional angiograms. Statistical comparison between the two groups was determined by using the χ2 test.Results.A total of 126 infants and children younger than 6 years of age underwent 134 CT examinations. Eighty-eight were obtained with a SDCT (65%) (group 1) and 46 with a MDCT (35%) (group 2). Sedation was required in 31/88 (35%) CT examinations in group 1 and in 6/46 (13%) in group 2. Conventional angiography was performed in 20/88 (22%) cases in group 1 and in 6/46 (13%) in group 2. Motion artefacts were present in 8/88 (9%) CT examinations in group 1 and in 4/46 (8%) in group 2. There was significant statistical difference with regard to sedation and angiography rates between the two groups (p<0.001) whereas there was no significant difference with regard to motion artefacts (p>1).Conclusions.MDCT can reduce the need for sedation and conventional angiography in children after liver transplantation. There is no effect on patient motion artefacts.

Blunt bowel and mesenteric trauma: role of clinical signs along with CT findings in patients’ management

BackgroundBowel and/or mesentery injuries represent the third most common injury among patients with blunt abdominal trauma. Delayed diagnosis increases morbidity and mortality. The aim of our study was to evaluate the role of clinical signs along with CT findings as predictors of early surgical repair.Material and methodsBetween March 2014 and February 2017, charts and CT scans of consecutive patients treated for blunt abdominal trauma in two different trauma centers were reread by two experienced radiologists. We included all adult patients who underwent contrast-enhanced CT of the abdomen and pelvis with CT findings of blunt bowel and/or mesenteric injury (BBMI). We divided CT findings into two groups: the first included three highly specific CT signs and the second included six less specific CT signs indicated as “minor CT findings.” The presence of abdominal guarding and/or abdominal pain was considered as “clinical signs.” Reference standards included surgically proven BBMI and clinical follow-up. Association was evaluated by the chi-square test. A logistic regression model was used to estimate odds ratio (OR) and confidence intervals (CI).ResultsThirty-four (4.1%) out of 831 patients who sustained blunt abdominal trauma had BBMI at CT. Twenty-one out of thirty-four patients (61.8%) underwent surgical repair; the remaining 13 were treated conservatively. Free fluid had a significant statistical association with surgery (p = 0.0044). The presence of three or more minor CT findings was statistically associated with surgery (OR = 8.1; 95% CI, 1.2–53.7). Abdominal guarding along with bowel wall discontinuity and extraluminal air had the highest positive predictive value (100 and 83.3%, respectively).ConclusionIn patients without solid organ injury (SOI), the presence of free fluid along with abdominal guarding and three or more “minor CT findings” is a significant predictor of early surgical repair. The association of bowel wall discontinuity with extraluminal air warrants exploratory laparotomy.

Atrial fibrillation, an epiphenomenon of acute Stanford type-A aortic dissection with suspected intimo-intimal intussusception

Supraventricular arrhythmias can sometimes be “only” epiphenomena appearing during acute hypoxia, pneumonia, pulmonary embolism, and thrombosis. Indeed, atrial fibrillation is not rare in acute aortic dissection as it is estimated in about one half of patients and may be secondary to a perfusion deficit of the sinoatrial node artery.

Splenosis of the abdomen and pelvis complicated by torsion of a splenic implant clinically mimicking an acute bowel ischemia

We present a case of splenosis of the abdomen and pelvis complicated by torsion of a splenic implant in a young female patient clinically mimicking an acute bowel ischemia. Splenosis is a benign condition defined as heterotopic auto-transplantation of splenic tissue throughout different body areas. It may occur after rupture of the spleen, either traumatic or secondary to surgical procedures. Although the presence of heterotopic splenic tissue is often asymptomatic and an incidental finding, it may present with sudden abdominal pain and bleeding. CT and MRI play a critical role in the detection of splenosis-related complications, such as torsion of the vascular pedicle and infarction. Splenosis torsion is extremely rare and it is still a diagnostic dilemma; the complication of abdominal splenosis should be considered in the differential diagnosis in patients with previous splenectomy.

Synchronous Meckel's diverticulum and gastrointestinal stromal tumour presenting as acute bleeding

A 34-year-old Caucasian male presented at our Emergency epartment with severe abdominal pain of increase intenity and melena. Oesophagogastroduodenoscopy (EGDS) showed aemorrhagic gastritis, whereas ultrasonography demonstrated a yperechoic mass of 5 cm×5 cm in diameter located at the left liac fossa, apparently separated from the urinary bladder. Multietector CT angiography (MDCTA) confirmed the presence of a ound, well demarcated, non-homogeneous mass adjacent to the rinary bladder and to the small bowel (arrows, Fig. 1). There were o CT signs of invasion with regard to the surrounding adipose issue and the urinary bladder.

TC a singolo detettore versus TC a detettore multiplo: Confronto fra sedazione, angiografie convenzionali ed artefatti da movimento, nei pazienti pediatrici dopo trapianto epatico

Purpose.The aim of this study was to determine whether the use of multidetector computed tomography (MDCT) is associated with decreased sedation, frequency of motion artefacts and conventional angiograms compared with single-detector CT (SDCT).Materials and methods.CT examinations performed in young children between January 1993 and June 2005 were reviewed retrospectively. Prior to September 2000, SDCT was used; after that period, MDCT was used. The examinations obtained during these two periods were compared for the frequency of sedation, motion artefacts, and conventional angiograms. Statistical comparison between the two groups was determined by using the χ2 test.Results.A total of 126 infants and children younger than 6 years of age underwent 134 CT examinations. Eighty-eight were obtained with a SDCT (65%) (group 1) and 46 with a MDCT (35%) (group 2). Sedation was required in 31/88 (35%) CT examinations in group 1 and in 6/46 (13%) in group 2. Conventional angiography was performed in 20/88 (22%) cases in group 1 and in 6/46 (13%) in group 2. Motion artefacts were present in 8/88 (9%) CT examinations in group 1 and in 4/46 (8%) in group 2. There was significant statistical difference with regard to sedation and angiography rates between the two groups (p<0.001) whereas there was no significant difference with regard to motion artefacts (p>1).Conclusions.MDCT can reduce the need for sedation and conventional angiography in children after liver transplantation. There is no effect on patient motion artefacts.