Posteroinferior labral cleft at direct CT arthrography of the shoulder by using multidetector CT: is this a normal variant?
ABSTRACT To describe a posterior labral cleft at direct computed tomographic (CT) arthrography of the shoulder by using multidetector CT and to compare this finding with a true posterior labral tear.
Institutional ethics review board approval was obtained, and informed consent was waived. One hundred twenty-seven shoulders in 126 patients were examined with direct CT arthrography by using 16- or 64-section multidetector CT and arthroscopy. Two musculoskeletal radiologists retrospectively reviewed CT arthrographic images for the presence, location, and size of a posterior labral tear, defined as a detectable contrast material-filled focal discontinuity of the labrum on an axial image, proved by using arthroscopy. A posterior labral cleft was defined as a false-positive lesion at CT arthrography that was proved to be a normal finding arthroscopically. Sensitivity, specificity, accuracy, positive and negative predictive values of tears and clefts were determined; incidence according to the patient's age and sex and the laterality (right or left shoulder), location, and size of the lesion were compared.
In 127 shoulders, radiologists 1 and 2 found 12 and 11 posterior labral tears, respectively, seen exclusively in male patients with posterior instability. Radiologist 1 observed 24 (18.9%) clefts, and radiologist 2 observed 20 (15.7%) clefts, seen more commonly in female patients (P = .037 for radiologist 1, P = .026 for radiologist 2) and in the inferior quadrant of the posterior labrum (along 7- to 8-o'clock positions, P < .05 for both radiologists); these clefts were shallower than labral tears (P = .005 for radiologist 1, P = .025 for radiologist 2).
At direct CT arthrography, a labral cleft may be a normal variation of the posterior labrum.
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ABSTRACT: To compare the image quality of shoulder CT arthrography performed using 120 kVp and 140 kVp protocols. Fifty-four CT examinations were prospectively included. CT scans were performed on each patient at 120 kVp and 140 kVp; other scanning parameters were kept constant. Image qualities were qualitatively and quantitatively compared with respect to noise, contrast, and diagnostic acceptability. Diagnostic acceptabilities were graded using a one to five scale as follows: 1, suboptimal; 2, below average; 3, acceptable; 4, above average; and 5, superior. Radiation doses were also compared. Contrast was better at 120 kVp, but noise was greater. No significant differences were observed between the 120 kVp and 140 kVp protocols in terms of diagnostic acceptability, signal-to-noise ratio, or contrast-to-noise ratio. Lowering tube voltage from 140 kVp to 120 kVp reduced the radiation dose by 33%. The use of 120 kVp during shoulder CT arthrography reduces radiation dose versus 140 kVp without significant loss of image quality.Korean journal of radiology: official journal of the Korean Radiological Society 11/2014; 15(6):739-45. DOI:10.3348/kjr.2014.15.6.739 · 1.81 Impact Factor
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ABSTRACT: This article reviews the normal labral variants of the shoulder and describes imaging features, including secondary signs, to help discriminate tears from normal variants. The labral variants can be divided into two main groups. One group is composed of nonstandard appearances in the labral shape, signal intensity, or the site of affixation to the glenoid rim. The other group consists of classic labral variants, where the labrum is partially or completely unattached to the subjacent bone, or a segment of the labrum is absent.Seminars in musculoskeletal radiology 09/2014; 18(4):365-73. DOI:10.1055/s-0034-1384826 · 0.95 Impact Factor
Article: Imaging of glenoid labrum lesions.[Show abstract] [Hide abstract]
ABSTRACT: This article reviews the current status of the imaging of the glenoid labrum and associated structures, including anatomic variants and the different types of labral disease.Clinics in sports medicine 07/2013; 32(3):361-90. DOI:10.1016/j.csm.2013.04.001 · 2.58 Impact Factor