Is Mediolateral Translation of Femur Caused by Total Knee Arthroplasty Being Ignored?

Purpose: This study aims to show the change in overall congruency due to mediolateral translation after total knee arthroplasty compared with normal knee anatomy. Methods: This study was performed in two parts. In part 1, the relationship between femur and tibia was defined by new parameters on the antero-posterior radiographs of 84 patients. In part 2, this relationship was evaluated on the postoperative radiographs of 136 total knee arthroplasty patients. Two parallel lines to the tibial anatomical axis were drawn tangent to the most lateral and most medial parts of the tibial plateau. After creating medial and lateral tangential lines, the distance between the most lateral point of the lateral femoral epicondyle and lateral tangential line and the most medial point of the medial femoral epicondyle and medial tangential line was measured. Another new parameter described in the study is epicondylar distance ratio. The ratios between the shortest distance between tibial anatomical axis and lateral femoral epicondyle and the distance between tibial anatomical axis and medial femoral epicondyle were defined. Results: It was found that the lateral tangent was not superposed in any measurement to the femoral lateral condyle, the closest tangent was passed, and the mean lateral space distance was 1.8 mm (SD 1.5, 95% CI 0-5.3 mm). The medial tangent was passed from the lateral to the femoral medial epicondyle, and the medial crossing distance was 8.5 mm (SD 5.7, 95% CI 5-14 mm). Epicondylar distance ratio used as the second measurement was 0.8 (0.5-0.9). After total knee arthroplasty measurements showed that the line passing through the lateral tibia crossed the lateral epicondyle of the femur and intersected at an average distance of 4.3 mm (SD 4.1, 95% CI 1-11.2 mm). Conclusions: There is a coronal plane congruence between tibia and femur in the healthy knees, which get changed after total knee arthroplasty.

Volumetric evaluation of the subacromial space in shoulder impingement syndrome.

INTRODUCTION: Shoulder impingement syndrome is evaluated radiologically with two-dimensional measurement parameters. None of these measurement parameters accurately reflect the three-dimensional geometry. The purpose of this study was to evaluate the volumetric status of the subacromial space in patients with shoulder impingement syndrome and to investigate its relationship with two-dimensional parameters. HYPOTHESIS: The primary hypothesis of this study is that subacromial volume is reduced in patients with impingement syndrome. The second hypothesis is that the sagittal plane morphology of the acromion reflects the subacromial volume better than the coronal plane morphology. PATIENTS AND METHODS: This retrospective study consisted of a total of 52 participants: 26 patients with impingement syndrome and 26 controls. Volumetric measurements were performed with using magnetic resonance imaging. The relationship between humerus and acromion was evaluated by acromiohumeral distance. The sagittal plane morphology of the acromion was evaluated with an objective acromial angle, while the coronal plane morphology was evaluated with a lateral acromial angle. The radiological parameters between groups were compared. RESULTS: The mean subacromial volume was significantly smaller in the impingement group compared to the control group (p=0.01). The subacromial volume had a negative correlation with the objective acromial angle (R=-0.46; p=0.01) The mean tendon volume was significantly higher in the impingement group (p<0.001). The mean acromiohumeral distance in the impingement group (6.8mm±1.0mm), was calculated to be significantly lower than the control group (10.1mm±1.5mm) (p<0.001). There was a positive moderate correlation between subacromial volume and acromiohumeral distance (R=0.61; p=0.01). DISCUSSION: This is the first study to demonstrate a reduction in subacromial volume in patients with impingement syndrome. The sagittal plane morphology of the acromion, rather than the coronal plane, appears to be more closely related to the subacromial volume. LEVEL OF EVIDENCE: III; case-control study.

Myelodysplastic Syndrome Presenting With Diffuse Bone Marrow Uptake on 68Ga-PSMA PET/CT.

We present the case of a 67-year-old man with prostate cancer who had no findings of recurrence, except diffuse radiotracer uptake in the bone marrow in Ga-PSMA PET/CT. Bone marrow uptake was also represented as multiple focal increased spots without any corresponding lytic or sclerotic lesions in CT. MRI revealed a high and homogeneous T2 signal within the bone marrow, without any contrast-enhanced or diffusion-restricted lesions. Further workup, including a bone marrow biopsy, revealed the diagnosis of myelodysplastic syndrome.

Sacroiliitis during isotretinoin treatment: Causal association or coincidence?

Isotretinoin, a retinoid derivate used in acne treatment, has a variety of side effects involving the musculoskeletal system; however, sacroiliitis is rarely observed. Our aim was to present nine cases of sacroiliitis in patients being treated with isotretinoin. Sacroiliitis was identified and monitored using magnetic resonance imaging (MRI). Clinical symptoms were resolved with nonsteroidal anti-inflammatory drug therapy after isotretinoin treatment was ceased. Different from the other cases, follow-up MRI was done. Follow-up MRI revealed improvement in some patients. Although the association between isotretinoin therapy and sacroiliitis has been covered in literature, this association is not yet completely understood. We aimed to discuss the relationship between two.

A new MRI grading system for chondromalacia patellae.

Background Chondromalacia patellae is a very common disorder. Although magnetic resonance imaging (MRI) is widely used to investigate patellar cartilage lesions, there is no descriptive MRI-based grading system for chondromalacia patellae. Purpose To propose a new MRI grading system for chondromalacia patellae with corresponding high resolution images which might be useful in precisely reporting and comparing knee examinations in routine daily practice and used in predicting natural course and clinical outcome of the patellar cartilage lesions. Material and Methods High resolution fat-saturated proton density (FS PD) images in the axial plane with corresponding T2 mapping images were reviewed. A detailed MRI grading system covering the deficiencies of the existing gradings has been set and presented on these images. Two experienced observers blinded to clinical data examined 44 knee MR images and evaluated patellar cartilage changes according to the proposed grading system. Inter- and intra-rater validity testing using kappa statistics were calculated. Results A descriptive and detailed grading system with corresponding FS PD and T2 mapping images has been presented. Inter-rater agreement was 0.80 (95% confidence interval [CI], 0.71-0.89). Intra-rater agreements were 0.83 (95% CI, 0.74-0.91) for observer A and 0.79 (95% CI, 0.70-0.88) for observer B (k-values). Conclusion We present a new MRI grading system for chondromalacia patellae with corresponding images and good inter- and intra-rater agreement which might be useful in reporting and comparing knee MRI examinations in daily practice and may also have the potential for using more precisely predicting prognosis and clinical outcome of the patients.

Diffusion Tensor Imaging of the Uterine Zones Related to the Menstrual Cycle and Menopausal Status at 3 Tesla MRI.

BACKGROUND: Diffusion and diffusion tensor imaging techniques (DTI) are widely available and used both in central nervous system and body imaging, including gynecological diseases. AIMS: The aims of this study were to assess the capability of DTI of uterine zones in relation to the menstrual cycle and ascertain the normal apparent diffusion coefficient and fractional anisotropy values at 3T magnetic resonance imaging (MRI). STUDY DESIGN: Prospective clinical study. METHODS: A total of 13 young reproductive and 12 postmenopausal healthy volunteers were included in the study. MRI examination included sagittal T2-weighted and single-shot echo planar imaging DTI obtained under free breathing. Fractional anisotropy (FA) values of the endometrium, junctional zone, and myometrium were determined. RESULTS: The median (minimum-maximum) FA of the endometrium, myometrium, and junctional zone of the reproductive group were 0.31 (0.260-0.465), 0.42 (0.302-0.664), and 0.58 (0.420-0.745), respectively, in the proliferative phase and 0.26 (0.180-0.413), 0.48 (0.357-0.656), and 0.59 (0.490-0.675)], respectively, in the secretory phase. In the postmenopausal group, the FA values of the endometrium, myometrium, and junctional zone were 0.275 (0.136-0.425), 0.255 (0.191-0.553), and 0.27 (0.129-0.397), respectively. Apparent diffusion coefficient (ADC) values of the endometrium, myometrium, and junctional zone of the reproductive group were 1.25±0.254 (0.970-1.463), 1.67 (1.213-1.854), and 1.23 (0.853-1.301), respectively, in the proliferative phase and 1.32±0.283 (1.165-1.706), 1.55 (1.360-1.791), and 1.17 (1.163-1.705), respectively, in the secretory phase. In the postmenopausal group, the ADC values of the endometrium, myometrium, and junctional zone were measured as 1.100±0.192 (0.850-1.302), 1.14 (0.864-1.283), and 1.09 (0.912-1.291). The FA values of the endometrium and myometrium were lower in the secretory phase of the reproductive group, while ADC values were higher. However, both the FA and ADC values were lower in the postmenopausal group. CONCLUSION: The present study showed that uterine DTI is feasible when used quantitatively. While FA values tend to decrease, ADC values increase significantly in all zones in the secretory phase except the junctional zone. Zonal FA and ADC values of postmenopausal women are lower in comparison to those in young women.

Ganglion cyst associated with triangular fibrocartilage complex tear that caused ulnar nerve compression.

Ganglions are the most frequently seen soft-tissue tumors in the hand. Nerve compression due to ganglion cysts at the wrist is rare. We report 2 ganglion cysts arising from triangular fibrocartilage complex, one of which caused ulnar nerve compression proximal to the Guyon's canal, leading to ulnar neuropathy. Ganglion cysts seem unimportant, and many surgeons refrain from performing a general hand examination.

Diffusion tensor imaging in carpal tunnel syndrome.

PURPOSE: We aimed to investigate the efficacy of diffusion tensor imaging in the diagnosis of carpal tunnel syndrome and to obtain a quantitative parameter that may contribute to the diagnosis. MATERIALS AND METHODS: The median nerves in 57 wrists of 38 patients diagnosed as carpal tunnel syndrome and 30 wrists of 24 normal subjects were prospectively evaluated with a 3T Philips scanner, using standard 8-channel SENSE head coil. Diffusion tensor imaging was performed using spin echo-echo planar imaging. For anatomical reference, a T1-weighted sequence was acquired. Fractional anisotropy and apparent diffusion coefficient measurements were done focally at the carpal tunnel level and from whole median nerve. RESULTS: In carpal tunnel syndrome patients, both focal carpal tunnel and whole nerve measurements demonstrated statistically significantly lower fractional anisotropy values than normal subjects (P < 0.001). No statistically significant difference was observed in apparent diffusion coefficient measurements. The cut-off value obtained by receiver operator characteristics analysis was 0.554 for focal carpal tunnel fractional anisotropy (sensitivity, 80%; specificity, 80%) and 0.660 for whole nerve fractional anisotropy (sensitivity, 82%; specificity, 80%) measurement. CONCLUSION: Diffusion tensor imaging may contribute to the diagnosis of carpal tunnel syndrome on the basis of fractional anisotropy measurements.

Diffusion tensor imaging in the differentiation of adrenal adenomas and metastases.

PURPOSE: To determine the utility of diffusion tensor imaging for the differentiation of adrenal adenomas and metastases. MATERIALS AND METHODS: Thirty-three patients with a mean age of 59 years were included in this study. Each subject presented with a single adrenal lesion (19 adenomas, 14 metastases). Magnetic resonance imaging (MRI) was performed in the coronal plane using a 3 Tesla MRI and a six-channel phased array SENSE torso coil. T1-weighted in-phase and opposed-phase, T2-weighted turbo spin-echo, and single-shot echo-planar diffusion tensor imaging (DTI) sequences were used for image acquisition. To determine apparent diffusion coefficients (ADC) and fractional anisotropy (FA) values of adrenal lesions, coronal T2-weighted images were used as anatomical references and to localize regions of interest on DTI images. The signal intensity (SI) indices were obtained from in-phase/opposed-phase images by a radiologist blinded to the DTI findings. The DTI parameters were determined by a different radiologist. The SI indices and the differences in FA and ADCs between adenomas and metastases were compared. Analyses of receiver operating characteristics (ROC) were performed to determine the area under the curve (AUC). RESULTS: The SI index of adenomas was found to be significantly higher than the value determined for metastases. Moreover, the median FA value of adrenal adenomas was found to be significantly higher than that of metastases. No statistically significant difference was observed in the ADCs between adenomas and metastases. Furthermore, no significant correlation was found among the SI index and the measured DTI parameters. Based on ROC analyses, the AUC was found to be 0.936 in FA measurements with a 95% confidence interval. The cutoff value obtained from this analysis was 0.40 with maximum sensitivity and specificity values of 74% and 88%, respectively. CONCLUSION: Although no significant difference was observed in the ADCs between adrenal adenomas and metastases, the FA values differed significantly. The FA values may have the potential to differentiate between adrenal adenomas and metastases, which is a possibility that should be validated by further research.

Prediction of semitendinosus and gracilis autograft sizes for ACL reconstruction.

PURPOSE: The aim of this study was to predict the hamstring graft sizes prior to anterior cruciate ligament reconstruction surgery in adults by using preoperative magnetic resonance imaging (MRI). METHODS: Fifty-one patients with anterior cruciate ligament rupture were prospectively evaluated. Diameter and cross-sectional areas of the gracilis and the semitendinosus tendons at two different levels were measured separately by preoperative MRI. In surgery, harvested gracilis and semitendinosus tendons were measured individually (2-stranded) and together (4-stranded) by using a graft sizing block. Radiological and operative sizes of the grafts were compared by Pearson's correlation test. ROC analysis was done to determine a possible cutoff value for the preoperative measurements. RESULTS: There were statistically significant correlations between the MR cross-sectional areas of gracilis, semitendinosus, gracilis + semitendinosus and intraoperative graft sizes of 2-stranded gracilis, 2-stranded semitendinosus and 4-stranded gracilis + semitendinosus tendons [P < 0.05]. No significant correlation was observed between the MR diameters of the gracilis, semitendinosus, gracilis + semitendinosus tendons and intraoperative graft sizes of 2-stranded gracilis, 2-stranded semitendinosus and 4-stranded gracilis + semitendinosus tendons [n.s]. CONCLUSION: Cross-sectional areas of the hamstring tendons in MR images can be used to estimate the sizes of hamstring grafts prior to anterior cruciate ligament reconstruction surgery which may be very helpful to predict possible graft insufficiencies and take precautions if needed. LEVEL OF EVIDENCE: Level IV.

Diffusion tensor imaging of the kidney at 3 Tesla MRI: normative values and repeatability of measurements in healthy volunteers.

PURPOSE: To evaluate the feasibility of renal diffusion tensor imaging and determine the normative fractional anisotropy and apparent diffusion coefficient values at 3 Tesla magnetic resonance imaging (MRI) using parallel imaging and free breathing technique. MATERIALS AND METHODS: A total of 52 young healthy volunteers with no history of renal disease were included in the study. MRI examinations were performed with 3 Tesla MRI equipment, using six-channel phased array SENSE Torso coil. In all subjects, T2-weighted turbo spin echo and diffusion tensor imaging using single shot echo planar imaging sequences were obtained in the coronal plane with free breathing. Field of view, slice thickness, and slice gap values were identical for both sequences for anatomic correlation during analysis of diffusion tensor imaging data. Parallel imaging method was used with a SENSE factor of 2. Diffusion tensor parameters of the cortex and medulla were determined and the intra- and inter-observer measurement variances were calculated. RESULTS: The mean fractional anisotropy of the medulla was significantly higher than that of the cortex, whereas the mean apparent diffusion coefficient of the medulla was lower when compared with that of the cortex. According to the two-sided paired samples Student's t test, the intra- and inter-observer measurements correlated well. CONCLUSION: This study shows the feasibility of renal diffusion tensor imaging and repeatibility of diffusion tensor parameter measurements in 3 Tesla MRI.

The evaluation of saphenofemoral insufficiency in primary adult varicocele.

The aim of this study was to evaluate the possible relationship between varicocele and saphenofemoral insufficiency in patients diagnosed with primary varicocele. A total of 70 patients with the primary diagnosis of varicocele were included into the study. A total of 30 age-matched healthy adults were also included in the study as a control group. Varicocele was diagnosed by palpation and observation of each spermatic cord in standing position before and during a valsalva maneuver. Additionally, scrotal Doppler and lower extremity venous Doppler ultrasonography were performed. Patients who were with spermatic varicose vein larger than 3.0 mm were included in the study group as a varicocele patient. At the lower extremity venous Doppler ultrasonography, a retrograde flow lasting longer than 0.5 seconds during normal breathing or at the valsalva maneuver was considered to be meaningful for saphenofemoral junction insufficiency. Thirty-six (51.35%) patients had insufficiency in saphenofemoral junction in the study group (6 [8.5%] bilateral, 30 [42.85%] unilateral) whereas 8 (26.6%) had insufficiency in the control group (2 [6.6%] bilateral, 6 [20%] unilateral insufficiency). The patients with primary varicocele had a statistically significant (P = .02) higher rate of venous insufficiency in their saphenofemoral junctions when compared with the control group. In the present study, the rate of saphenofemoral insufficiency has been found to be statistically higher in patients with primary varicocele compared with healthy men. Depending on the common presence of valvular insufficiency, we believe that the presence of varicocele should be investigated in the young population suffering from saphenofemoral junction insufficiency.

Diagnostic utility of DTI in prostate cancer.

PURPOSE: The aim of this study was to compare the diffusion tensor parameters of prostate cancer, prostatitis and normal prostate tissue. MATERIALS AND METHODS: A total of 25 patients with the suspicion of prostate cancer were included in the study. MRI was performed with 3 T system (Intera Achieva, Philips Medical Systems, The Netherlands). T2 TSE and DTI with ss-EPI were obtained in each subject. TRUS-guided prostate biopsy was performed after the MRI examination. Images were analyzed by two radiologists using a special software system. ROI's were drawn according to biopsy zones which are apex, midgland, base and central zone on each sides of the gland. FA and ADC values in areas of cancer, chronic prostatitis and normal prostate tissue were compared using Student's t-test. RESULTS: Histopathological analysis revealed carcinoma in 68, chronic prostatitis in 67 and was reported as normal in 65 zones. The mean FA of cancerous tissue was significantly higher (p<0.01) than the FA of chronic prostatitis and normal gland. The mean ADC of cancerous tissue was found to be significantly lower (p<0.01), compared with non-cancerous tissue. CONCLUSION: Decreased ADC and increased FA are compatible with the hypercellular nature of prostate tumors. These differences may increase the accuracy of MRI in the detection of carcinoma and to differentiate between cancer and prostatitis.

Diffusion-weighted imaging of the rectosigmoid colon: preliminary findings.

OBJECTIVES: The aims of this study were to determine and evaluate the apparent diffusion coefficient (ADC) values of the rectal wall for identifying inflammatory bowel disease (IBD) and rectosigmoid (rectum and sigmoid colon) malignancies. METHODS: Diffusion-weighted magnetic resonance imaging (DWI) findings of 23 patients (mean age, 57 years) consisting of 14 patients with rectosigmoid adenocarcinomas and 9 patients with IBD (6 with ulcerative colitis and 3 with Crohn disease) were retrospectively reviewed. In addition, 30 healthy controls (mean age, 45 years) were enrolled in the study. Diffusion-weighted imaging was performed with b factors of 0, 500, and 1000 s/mm2. RESULTS: The mean (SD) ADC values of the control, IBD, and rectosigmoid adenocarcinoma groups were 1.47 (0.19) x 10(-3) mm2/s, 1.37 (0.12) x 10(-3) mm2/s, and 0.97 (0.14) x 10(-3) mm2/s, respectively. Among the patients with IBD, 2 were in the active, and the rest were in the inactive period, with mean (SD) ADC values of 1.21 (0.08) x 10(-3) and 1.42 (0.09) x 10(-3), respectively. The ADC values of the normal rectum and rectosigmoid malignancy group and rectosigmoid carcinoma and IBD groups were significantly different (P < 0.01). A cutoff value for carcinomas of 1.14 x 10(-3) mm2/s yielded a sensitivity and specificity of 93.3% and 93.3%, respectively. CONCLUSIONS: Our preliminary findings show that quantitative DWI may be able to differentiate the normal rectum from neoplastic involvement, in addition to distinguishing between inflammatory and neoplastic involvements. However, radiologists should be aware of possible overlaps that may lead to misdiagnoses when DWI is used alone.

Diffusion-weighted imaging of the renal and adrenal lesions.

OBJECTIVES: The purpose of this study was to calculate the apparent diffusion coefficient (ADC) values of different renal and adrenal lesions to evaluate the ability of diffusion-weighted imaging in characterizing masses and determining malignancy. METHODS: A total of 52 patients consisting of 67 renal lesions and 28 patients with 33 adrenal lesions in addition to 50 healthy controls with normal kidneys were enrolled in the study. Diffusion-weighted imaging was performed with b factors of 0, 500, and 1000 s/mm2, and the ADCs of the normal kidney and renal and adrenal lesions were calculated. RESULTS: The mean (SD) ADCs of the renal cortex and medulla of the control group were 2.08 (0.22) x 10(-3) and 1.94 (0.18) x 10(-3) mm2/s, respectively. Focal renal lesions were as follows: simple cysts (2.94 [0.20] x 10(-3) mm2/s), hemorrhagic cysts (1.71 [0.38] x 10(-3) mm2/s), angiomyolipomas (1.40 [0.21] x 10(-3) mm2/s), renal cell carcinomas (1.06 [0.39] x 10(-3) mm2/s), metastases (1.50 [0.13] x 10(-3) mm2/s), and hydronephrosis (1.54 [0.25] x 10(-3) mm2/s). The mean ADCs of all these pathologies were significantly different when compared with normal parenchyma. Diffusion-weighted imaging was also able to differentiate angiomyolipomas and hemorrhagic cysts from renal cell carcinomas. Adrenal lesions were subgrouped as adenomas (1.41 [0.27] x M10(-3) mm2/s), nonadenomatous solid masses (1.08 [0.28] x 10(-3) mm2/s), and cysts (2.82 [0.24] x 10(-3) mm2/s). The mean ADCs of adenomas were significantly different when compared with nonadenomatous solid masses and cysts. CONCLUSIONS: Our findings show that ADC measurement has a potential ability to differentiate benign and malignant focal renal and adrenal lesions with the guidance of conventional sequences. When used alone, diffusion-weighted imaging may lead to misdiagnoses due to overlapping ADCs of the lesions.

Diffusion-weighted MRI of urinary bladder and prostate cancers.

PURPOSE: The purpose of this study was to evaluate the feasibility of diffusion-weighted imaging in the diagnosis of the urinary bladder and prostate carcinomas. The apparent diffusion coefficient (ADC) values of the malignant and normal tissues were correlated. MATERIALS AND METHODS: A total of 23 patients with 14 urinary bladder carcinomas and 9 prostate carcinomas, and 50 healthy controls with normal ultrasonographic urinary bladder and prostate gland imaging findings were enrolled in the study. The ADC values were reported as the mean +/- standard deviation. Student's t test was performed to compare the ADC values of the normal and pathological tissues. Diffusion-weighted imaging (DWI) was performed with b factors of 0, 500, and 1000 s/mm(2), and the ADC values of the normal tissues and lesions were calculated. RESULTS: The mean ADC value of the urinary bladder wall of the control group and bladder carcinomas were (2.08 +/- 0.22 x 10(-3)mm(2)/s) and (0.94 +/- 0.18 x 10(-3)mm(2)/s), respectively. In addition, the ADC values of the normal peripheral (2.07 +/- 0.33 x 10(-3)mm(2)/s), transitional zones (1.46 +/- 0.23 x 10(-3)mm(2)/s) of the prostate, seminal vesicles (2.13 +/- 0.13 x 10(-3)mm(2)/s) and the prostate carcinomas (1.06 +/- 0.17 x 10(-3)mm(2)/s) were calculated. The comparison of mean ADC values of the peripheral-transitional zones of the prostate, normal bladder wall-bladder carcinomas, and peripheral zone prostate carcinomas were statistically significant (P < 0.01). CONCLUSION: The present study demonstrated that ADC measurement has a potential ability to differentiate carcinomas from normal bladder wall and prostate gland.

Diffusion-weighted imaging of adnexal torsion.

We report the diffusion-weighted imaging findings (DWI) of a case with ovarian torsion. Magnetic resonance imaging revealed a large cyst within a non-enhancing ovary. DWI depicted restricted diffusion which in turn was found to be related with the infarction of the ovary in the laparoscopic salpingo-oophorectomy performed.

Pediatric focal xanthogranulomatous pyelonephritis: dynamic contrast-enhanced MRI findings.

Xanthogranulomatous pyelonephritis (XPN) is the result of chronic renal infection. It is very rare in childhood and the focal form, which is said to be more common in children, is often misdiagnosed as a renal tumor. We report a case of a focal XPN in a 14-year-old girl. The true preoperative diagnosis may be very hard in children especially in the focal form but it seems to be possible by the help of dynamic contrast-enhanced MRI.