Evaluation of Chondromalacia in the Knee Joint using Three Dimensional Fourier Transformation Constructive Interference in Steady State(CISS)

PURPOSE: To assess the usefulness of three-dimensional Fourier transformation constructive interference in steady state (CISS) for the evaluation of chondromalacia. MATERIALS AND METHODS: In 110 knee joints which underwent both MR imaging and arthroscopy, the findings were retrospectively reviewed. MR imaging sequences included two-dimensional dual-echo turbo spin-echo imaging along the sagittal and coronal planes, two-dimensional fast low-angle shot (FLASH) with magnetization transfer along the axial plane, and three-dimensional CISS along the sagittal plane. After the cartilage surfaces of each joint were divided into eight areas (each medial and lateral area of patellar facets, trochlear surfaces, femoral condyles, and tibial plateaux), a total of 880 areas were assessed. Using both combined two-dimensional (2-D turbo spin-echo and FLASH) and CISS imaging during different sessions, each chondromalacia case was assigned one of five grades. RESULTS: Arthroscopy revealed the presence of chondromalacia in 162 areas. This was first grade in 77 areas, second grade in 38, third grade in 21, and fourth grade in 26. The sensitivity, specificity, and accuracy of 2-D and CISS imaging were 48.1%, 93.7% and 85.3%, and 45.7%, 95.3% and 86.1%, respectively. Agreement between MR and arthroscopic staging occurred in 81.48% of 2-D imaging procedures and 82.16% of CISS procedures. If a difference of one grade was accepted, these proportions rose to 84.32% and 85.22%, respectively, though this increase was statistically insignificant. CONCLUSION: Though CISS imaging was less sensitive than 2-D imaging in the grading of chondromalacia, additional CISS imaging can help improve the accuracy of this grading.

Usefulness of Dual-Echo in Steady State(DESS) Image in Chondromalacia of Knee Joint: Comparison of DESS and Turbo Spin-Echo MR Images

PURPOSE: To evaluate the usefulness of Dual Echo in State(DESS) image in the diagnosis of chondromalacia of the knee compared with turbo spin-echo MR images. MATERIALS AND METHODS: We included 26 patients with chondromalacia of the knee. MR imaging was obtained with a 1.5T imager. Sagittal and coronal double echo T2 weighted images(TR/TE 3000~4200/16-96msec, FOV 140-160140-160mm, matrix size 180256, slice thickness 4.0mm, interslice gap 0.5mm), and sagittal DESS image(TR/TE 25.4/9.0msec, flip angle 35-45, FOV 150-160150-160mm, matrix size 192256, effective slice thickness 1.5mm) were obtained. Cartilage lesions were staged according to a modified scheme proposed by Outerbridge: grade 0, normal; grade 1, softening or/and we swelling; grade 2, mild surface fibrillation or/and less than 50% of cartilage thickness; grade 3, severe surface fibrillation or/and loss of more than 50% of cartilage thickness but without exposure of subchondral bone; and grade 4, complete loss of cartilage with subchondral bone exposure. Gradings were determined by two readers with consensus, and patellofemoral, medial and lateral tibiofemoral compartments were evaluated. RESULTS: Arthroscopic findings revealed grade 1 in seven cases, grade 2 in 21 cases, grade 3 in six cases, and grade 4 in 18 cases. Sensitivity of turbo spin-echo MR images was as follows: 0%, 14%, 0%, 61% in each grade, and sensitivity of DESS image was as follows; 0%, 33%, 50%, 67% in each grade(p=0.001). In the detection of chondromalacic lesions regardless of gradings, sensitivity, specificity and accuracy of conventional MR image were 59.6%, 88.6%, 78.8% and of DESS image,73.1%, 88.4%, 82.2%(p=0.007). CONCLUSION: For chondromalacia of knee joints, DESS images showed higher sensitivity than turbo spinehco MR images. Therefore, DESS images will be helpful for diagnosis of chondromalacia of knee joints.

Tracheal Deviation in Thy roid Lesions: Correlation with Chest Radiograph

PURPOSE: To evaluate the prevalence and degree of tracheal deviation seen on chest PA radiographs of thyroid lesions and to correlate these findings with their size, volume, pattern (localized or diffuse), location, and constitution . MATERIALS AND METHODS: Between May 1995 and July 1998, tracheal deviation seen on chest PA radiographs was retrospectively reviewed in 179 consecutive cases in which a thyroid lesion was seen on ultrasonography and/or CT of the thyroid. The criterion of tracheal deviation was more than 3mm. Thyroid lesions were classified as diffuse or localized according to their pattern; as central, marginal or borderline on the basis of their location, and as cystic, solid or mixed, depending on their constitution. RESULTS: Tracheal deviation was seen in 53 cases (29.6%, n=179); mean deviation was 5.6mm (3 -27 mm). Its incidence increased with lesion size (p0.05). The volume of the former type was measured and the incidence and degree of tracheal deviation was found to increase with lesion volume (p0.05). The most common location was borderline (n=30, 65.2 %), followed by central (n=12, 26.1%), and marginal (n=4, 8.7%). The most common type by constitution was solid (n=32, 69.6 %), followed by cystic (n=10, 21.7 %), and mixed type (n=4, 8.7 %) (p>0.05). CONCLUSION: Chest PA radiography revealed tracheal deviation of thyroid lesion in 53 cases (29.6 %). The incidence and degree of deviation increased with increasing size and volume of the lesion, but deviation did not correlate with the pattern (localized or diffuse), location or constitution of the lesion.

Tracheal Deviation in Thy roid Lesions: Correlation with Chest Radiograph

PURPOSE: To evaluate the prevalence and degree of tracheal deviation seen on chest PA radiographs of thyroid lesions and to correlate these findings with their size, volume, pattern (localized or diffuse), location, and constitution . MATERIALS AND METHODS: Between May 1995 and July 1998, tracheal deviation seen on chest PA radiographs was retrospectively reviewed in 179 consecutive cases in which a thyroid lesion was seen on ultrasonography and/or CT of the thyroid. The criterion of tracheal deviation was more than 3mm. Thyroid lesions were classified as diffuse or localized according to their pattern; as central, marginal or borderline on the basis of their location, and as cystic, solid or mixed, depending on their constitution. RESULTS: Tracheal deviation was seen in 53 cases (29.6%, n=179); mean deviation was 5.6mm (3 -27 mm). Its incidence increased with lesion size (p0.05). The volume of the former type was measured and the incidence and degree of tracheal deviation was found to increase with lesion volume (p0.05). The most common location was borderline (n=30, 65.2 %), followed by central (n=12, 26.1%), and marginal (n=4, 8.7%). The most common type by constitution was solid (n=32, 69.6 %), followed by cystic (n=10, 21.7 %), and mixed type (n=4, 8.7 %) (p>0.05). CONCLUSION: Chest PA radiography revealed tracheal deviation of thyroid lesion in 53 cases (29.6 %). The incidence and degree of deviation increased with increasing size and volume of the lesion, but deviation did not correlate with the pattern (localized or diffuse), location or constitution of the lesion.

Increased Opacity of Left Pericardiac Area on Chest Radiograph: Correlation with CT Findings and its Frequency

PURPOSE: The purpose of this study was to evaluate the incidcnce of extrapericardial fat in the left cardiacborder, and with regard to left extrapericardial fat, to correlate chest radiographs with CT scans. MATERIALS AND METHODS: This study involved 132 consecutive patients who underwent chest PA and lateral radiographs, and chestCT scans. According to the results of chest PA radiograph, patients were divided into three groups: those with aclear left cardiac border; those with an indistinct left cardiac border; and those with an indistinct left cardiacborder with increased density; cardiophrenic angle, as seen on lateral radiograph, the presence of increaseddensity in the anterior cardiophrenic angle, as seen on lateral radiograph radiographs was evaluated. On the basisof the results of CT scanning, patients were classified into four groups according to the amount of leftextrapericardial fat: negative, minimum, moderate, and maximum. Left extrapericardial fat, as seen on CT, wascorrelated with the conspicuity of left cardiac border seen on PA radiograph and the presence of increased densityin the anterior cardiophrenic angle, as seen on lateral radiograph. RESULTS: On CT, left extrapericardial fat wasobserved in 51 patients (38.6%). In 38 of these (28.8%), the amount was minimal, in 12 (9.1%), it was moderate,and in one (0.8%), it was maximal. On posteroanterior chest radiograph, clear, indistinct, and indistinct andincreased density of the left cardiac border was seen in 89 (67.4%), 28 (21.2%), and 15 cases (11.4%),respectively. On lateral radiograph, increased density of the anterior cardiophrenic angle was seen in 115 cases(87.1%) but in 17 (12.9%), increase density was not apparent. There was significant correlation between chestradiographs and CT(p<0.001) (sensitivity: 53%; specificity: 100%; positive predictive value: 100%; negativepredictive value: 84%). CONCLUSION: The conspicuousness of the left cardiac border, as seen on PA chestradiograph, correlated with the presence of left extrapericardial fat, as seen on CT, and was related to theamount of left extrapericardial fat. Increased density of the anterior cardiophrenic angle, as seen on lateralradiographs, correlated with the presence of left extrapericardial fat on CT, but the absence of increased densityon lateral radiograph corresponds to the absence or a minimal amount of left extrapericardial fat, as seen on CT.