Helical CT of diaphragmatic rupture caused by blunt trauma.

Imaging hemidiaphragmatic injury

“…Use of relatively thick sections (5 mm or more) and motion-related artifacts significantly degrade quality of reformations obtained from single-slice systems. No DI that occurred without associated visceral herniation was diagnosed in the authors' retrospective study performed using single-detector spiral CT [19]. The use of axial CT only limits detection of DI since the axial plane is tangential to the diaphragm dome.…”

“…The CT "collar sign" has been reported as 100% specific, but with a limited sensitivity of 27-36% for diagnosing DI [33,40]. The authors performed a retrospective study [19] to determine sensitivity and specificity of single-slice spiral CT in diagnosing blunt diaphragm injury. Spiral CT was performed on 41 patients (32 had left hemidiaphragm injuries, ten right and one patient with bilateral hemidiaphragm injury) with chest radiographic findings suspicious for DI.…”

“…Also note extension of fat through the chest wall. b Sagittal MPR of same injury sensitive to detect left-sided DI [19]. Reformatted coronal and sagittal images were especially helpful for detection of subtle right-sided visceral herniation and to delineate the diaphragm outline.…”

Multi detector CT Imaging of Abdominal and Diaphragmatic Hernias: Pictorial Essay

“…It is more common on the left side due to an area of congenital posterolateral weakness on the left side and protective effect of the liver on the right hemidiaphragm [31][32][33][34]. Helical CT with thinner axial images and higher quality of reformatted images has proven to be more valuable in preoperative detection of traumatic diaphragmatic hernia (Fig.…”

“…CT signs of diaphragmatic injury include direct visualization of injury (free edge of the disrupted diaphragm demarcating the defect is seen), segmental diaphragm non-visualization (low specificity), intrathoracic herniation of viscera, collar sign (focal constriction of the herniated bowel or omentum ) which shows a high specificity of 80.7-100% [31,32], dependent viscera sign (viscera lies dependent against the posterior chest wall) which shows a specificity of 71-96.5% [32], diaphragm thickening, intramuscular hematoma and peridiaphragmatic active contrast extravasation.…”