Percutaneous Image-Guided Spinal Lesion Biopsies: Factors Affecting Higher Diagnostic Yield.

OBJECTIVE: The objectives of this study were to determine the diagnostic yield of percutaneous biopsy of osseous spinal lesions under CT and fluoroscopy guidance and to analyze lesion-related and technical factors affecting higher diagnostic yield. MATERIALS AND METHODS: We retrospectively reviewed 247 consecutive percutaneous spinal biopsies and recorded the following information: size, anatomic location, and bone matrix of lesions; guiding modality; years of attending physicians' experience; number of approaches; pathologic result of initial biopsy; and final diagnosis. The pathologic results of the initial biopsies were classified as diagnostic or nondiagnostic. All variables were compared using Pearson chi-square test or Fisher exact test. Multivariate logistic regression was also conducted. RESULTS: Of the initial 247 biopsies, 197 (80%) biopsies were diagnostic. On multivariate analysis, size, bone matrix, and final diagnosis of lesion were significant factors affecting biopsy yield. Biopsies of large lesions (≥ 20 mm) showed higher diagnostic yield than biopsies of small lesions (p = 0.006). Biopsies of lytic lesions had the highest diagnostic yield (88%), followed by biopsies of mixed (84%), sclerotic (67%), and isodense lesions (61%). Differences were significant for diagnostic yields of biopsies of lytic versus sclerotic lesions (p = 0.004) and lytic versus isodense lesions (p = 0.031). Biopsies of metastases had significantly highest diagnostic yield (97%), followed by biopsies of primary malignancies (84%) and benign lesions (39%) (p < 0.05). CONCLUSION: For percutaneous image-guided biopsies of spinal tumorous lesions, diagnostic yield was 80%. Size, bone matrix, and final diagnosis of lesions affected diagnostic yield of percutaneous image-guided biopsies.

Percutaneous CT-guided sternal biopsy: factors affecting the diagnostic yield.

Background Sternal lesions are occasionally seen in clinical practice and their diagnosis can be important, especially for oncologic patients. However, percutaneous computed tomography (CT)-guided biopsy of sternal lesions is rarely performed. Purpose To assess the diagnostic yield of percutaneous CT-guided sternal biopsies and to analyze the factors that affect diagnostic yield. Material and Methods A retrospective review of 34 patients who underwent CT-guided sternal biopsy was carried out at a single institution. Pre-biopsy CT density, location, penetration length of biopsy needle, number of biopsy attempts, angle of needle approach, final diagnosis, and operator experience level were recorded. A biopsy was considered as diagnostic if it provided a confident pathologic result. All variables were compared using Chi-square tests. Results Twenty-two of the 34 (64.7%) biopsy procedures yielded a diagnostic sample and 12 (35.3%) were non-diagnostic. Eight participants in the non-diagnostic group were clinically diagnosed with inflammatory arthritis of the manubriosternal or costosternal joints. Longer penetration distance of the tumor by the biopsy needle showed higher diagnostic yield ( P = 0.031). Osteoblastic lesions ( P < 0.001), lesions in the manubriosternal joint ( P = 0.018) and approaches using more obtuse angles ( P = 0.009) were associated with significantly lower diagnostic yields. Malignancy in the final diagnosis led to a higher diagnostic yield than benign lesions ( P < 0.001). Conclusion CT-guided percutaneous sternal biopsy has a relatively lower diagnostic yield. However, acute angle of needle approach may help increase biopsy success rate. Osteoblastic lesions and lesions in the manubriosternal joint tend to have lower diagnostic yield.

Sclerosing epithelioid fibrosarcoma: cytogenetic analysis of FUS rearrangement.

Sclerosing epithelioid fibrosarcoma (SEF) is a rare but distinct variant of fibrosarcoma. A 43-year-old man presented with a lesion in his back that had been present for three years but had recently increased in size. Magnetic resonance imaging (MRI) revealed a 6-cm sized ovoid mass showing low intensities on T1 and T2 weighted images. Histologically, the tumor was of moderate cellularity, and the cells were relatively uniform in size and shape. The cells were epithelioid, round, oval and polygonal with clear and slightly eosinophilic cytoplasm, forming nests, cords, or sheet-like patterns with a dense collagenous and hyalinized matrix. The tumor was positive for vimentin, but negative for smooth muscle actin, desmin, HMB45, and CD34. Although the tumor showed nuclear overexpression of beta-catenin protein, the CTNNB1 exon3 mutation was not detected. Fluorescent in situ hybridization for FUS using dual color break-apart probes showed rearrangement of the FUS. In accordance with previous studies, our case showed positive findings of FUS rearrangement, reinforcing the notion of a close relationship between low grade fibromyxoid sarcoma and SEF.

Analysis of cyclops lesions after different anterior cruciate ligament reconstructions: a comparison of the single-bundle and remnant bundle preservation techniques.

OBJECTIVE: The aim of this work was to compare the prevalence of cyclops lesions after anterior cruciate ligament reconstruction (ACLR) using the single-bundle and remnant bundle preservation techniques. MATERIALS AND METHODS: One hundred consecutive patients, who had undergone postoperative MRI of the knee followed by arthroscopic ACLR with the remnant bundle preservation technique (R) between February 2007 and August 2010, were enrolled in this study. Thirty-six consecutive patients who underwent ACLR using the single-bundle technique (S) were also included in this study as a control group. The MR findings were scored based on the presence of pre-ACL graft lesion as 0, 1, 2, or 3 on the sagittal images. The sixty-one specimens by second-look surgery (20 in S, 41 in R) were pathologically examined. RESULTS: The numbers of patients with scores of 0, 1, 2, and 3 were 1, 18, 14, and 3 in group S and 4, 60, 29, and 7, in group R, respectively. Of the 61 patients who underwent second-look surgery (20 in S, 41 in R), eight had a cyclops lesion (three in group S and five in group R). The prevalence of cyclops lesion was not significantly different in group R and group S (p = 0.761). CONCLUSIONS: The prevalence of a cyclops lesion was similar in both groups.

Differentiation between spinal subchondral bone metastasis with focal pathologic endplate fracture and oedematous Schmorl's node.

INTRODUCTION: We aimed to identify imaging-based findings that can differentiate between spinal subchondral bone metastasis with focal pathologic endplate fracture and oedematous Schmorl's nodes that have been histopathologically confirmed. METHODS: Between March 2010 and April 2016, 11 patients who had undergone spinal magnetic resonance (MR) imaging or computed tomography (CT) with final radiologic reports that included 'subchondral bone metastasis with focal pathologic endplate fracture' or 'edematous Schmorl's node' and had also undergone percutaneous imaging-guided spinal biopsies were included. Two radiologists retrospectively evaluated the following imaging features in consensus: size, location, presence of sclerotic margin, presence of intralesional or perilesional enhancement and opposite endplate enhancement of the involved disc, presence of disc height loss and presence of metabolic uptake at a corresponding lesion on nuclear medicine imaging. RESULTS: A total of 11 patients, including six patients with spinal subchondral bone metastasis with focal pathologic endplate fracture and five patients with oedematous Schmorl's nodes, were included in this study (median age, 58 years; range, 50-63 years; six men). Sclerotic margin (P = 0.002) and enhancement on the opposite endplate of the involved disc (P = 0.047) were significantly different between oedematous Schmorl's node and subchondral bone metastasis with focal pathologic endplate fracture. CONCLUSION: Sclerotic margin and enhancement on the opposite endplate of the involved disc suggest oedematous Schmorl's node rather than subchondral bone metastasis with focal pathologic endplate fracture. Decreased disc height is likely to be an oedematous Schmorl's node rather than subchondral bone metastasis with focal pathologic endplate fracture.

MRI findings of Aspergillus spondylitis.

OBJECTIVE: The aim of this retrospective study is to report the MRI findings of biopsyproven Aspergillus spondylitis. CONCLUSION: Aspergillus spondylitis should be suspected when multiple disk levels are involved with skip lesions or subligamentous spread on MRI. A serrated appearance of the vertebral endplates and subchondral T2 hypointensity are suggestive of Aspergillus spondylitis.

Indirect MR arthrographic findings of adhesive capsulitis.

OBJECTIVE: The objective of our study was to compare the indirect MR arthrographic findings of patients with adhesive capsulitis and patients without adhesive capsulitis. MATERIALS AND METHODS: Indirect MR arthrograms of 35 patients (21 women, 14 men; mean age, 50.1 years) diagnosed with adhesive capsulitis clinically were compared with indirect MR arthrograms of 45 patients (23 women, 22 men; mean age, 48.9 years) without adhesive capsulitis. Joint capsule thickness in the axillary recess and the thicknesses of the enhancing portion of the axillary recess and the rotator interval were, respectively, evaluated on coronal T2-weighted images and coronal and sagittal fat-suppressed enhanced T1-weighted images by two radiologists independently. Reliability was studied using the intraclass correlation coefficient (ICC). Receiver operating characteristic (ROC) curves were compared. RESULTS: Patients with adhesive capsulitis had significantly thickened joint capsules in the axillary recess and a thickened enhancing portion in the axillary recess and in the rotator interval. The difference in the thicknesses of the enhancing portion in the axillary recess and in the rotator interval were significantly greater than the difference in joint capsule thicknesses in the axillary recess between the adhesive capsulitis group and the control group (p < 0.001). Interobserver reliability was good for all three indexes (ICC ≥ 0.80). The area under the ROC curve for the thickness of the joint capsule in the axillary recess and the thicknesses of the enhancing portion of the axillary recess and the rotator interval were 0.797, 0.861, and 0.847, respectively. CONCLUSION: An abundance of enhancing tissue in the rotator interval and thickening and enhancement of the axillary recess are signs suggestive of adhesive capsulitis on indirect MR arthrography.

Imaging of primary chest wall tumors with radiologic-pathologic correlation.

Neoplasms and tumorlike lesions that originate from chest wall tissues are uncommon compared with tumors in other parts of the body, and unfamiliarity with these disease entities can cause diagnostic difficulties for radiologists. Furthermore, the imaging features of many of these tumors are nonspecific, particularly those that are locally aggressive. However, a systematic approach based on patient age, clinical history, lesion location, and characteristic imaging findings often helps limit the differential diagnosis. Primary chest wall tumors can be classified as bone or soft-tissue tumors, with the latter being further classified into adipocytic tumors, vascular tumors, peripheral nerve sheath tumors, cutaneous lesions, fibroblastic-myofibroblastic tumors, and so-called fibrohistiocytic tumors, largely based on the 2002 World Health Organization classification. Within each category, it is possible to further limit the differential diagnosis with cross-sectional imaging. Information on specific features (eg, mineralization, fibrosis, hemosiderin deposits) and imaging patterns (eg, the "target sign" and "fascicular sign" seen in neurogenic tumors) can aid in making the diagnosis. Radiologists can achieve a sufficiently specific diagnosis of bone tumors and soft-tissue tumors if typical findings are present.

3D isotropic turbo spin-echo intermediate-weighted sequence with refocusing control in knee imaging: comparison study with 3D isotropic fast-field echo sequence.

BACKGROUND: Three-dimensional (3D) turbo spin-echo (TSE) images have been used in imaging of the extremities and comparable diagnostic performance to two-dimensional (2D) TSE images has been reported in several studies. However, comparison of the 3D isotropic TSE intermediate-weighted sequence and 3D FFE sequence in terms of image quality has not been investigated. PURPOSE: To compare the image quality of a 3D isotropic TSE intermediate-weighted sequence with refocusing control (volume isotropic turbo spin echo acquisition [VISTA]) and a 3D isotropic fast-field echo (FFE) sequence of the knee joint. MATERIAL AND METHODS: 3.0 T knee MRI with VISTA and 3D FFE sequences was performed in 10 healthy volunteers (3 men, 7 women; age range 26-30 years). Two radiologists with specialties in the musculoskeletal system assessed tissue contrast between the fluid-cruciate ligament (F-L), fluid-meniscus (F-M), and fluid-cartilage (F-C) based on a 4-point scale (1, poor; 2, fair; 3, good; and 4, excellent). Statistical analysis for inter-observer agreement and differences in grades in tissue contrast between VISTA and 3D FFE images (Wilcoxon signed-rank) were performed. For a quantitative analysis, the signal-to-noise ratio (SNR) was obtained by imaging phantom and noise-only image. Image contrast ratios (CRs) were calculated between F-L, F-M, and F-C in volunteer images of VISTA and 3D FFE and compared statistically with a paired t-test. RESULTS: Based on qualitative analysis, VISTA had statistically superior grades of tissue contrast in F-L (P < 0.001) and F-M (P < 0.001). 3D FFE had superior but not statistically significant (P = 0.317) grades in F-C. Based on quantitative analysis, the SNR of the phantom imaging was higher in VISTA than that in 3D FFE (28.18 vs. 14.90). VISTA had superior CRs in F-L (P < 0.001) and F-M (P < 0.001). 3D FFE had superior CR in F-C (P = 0.038). CONCLUSION: The VISTA sequence was superior in tissue contrast between F-M and F-L, and 3D FFE was superior in tissue contrast between F-C, subjectively and quantitatively.

Localized tenosynovial giant cell tumor in both knee joints.

Tenosynovial giant cell tumor, previously called pigmented villonodular synovitis (PVNS), is a rare benign neoplastic process that may involve the synovium of the joint. The disorder is usually monoarticular and only a few cases have been reported on polyarticular involvement. Herein, we present a case of localized intra-articular tenosynovial giant cell tumor in a 29-year-old man involving both knee joints with a description of the MR imaging and histological findings.

Effectiveness of percutaneous cement injection on proximal junctional failure after posterior lumbar interbody fusion: Preliminary study.

Proximal junctional failure (PJF) is the greatest challenge after posterior lumbar interbody fusion (PLIF). The aim of this study was to evaluate the effectiveness of percutaneous cement injection (PCI) for PJF after PLIF patients requiring surgical revision.In this retrospective clinical study, we reviewed 7 patients requiring surgical revision for PJF after PLIF with 18 months follow-up. They received PCI at the collapsed vertebral body and supra-adjacent vertebra, with or without intervertebral disc intervention. The outcome measures were radiographic findings and revision surgery. Two different radiographic parameters (wedging rate (%) of the fractured vertebral body and local kyphosis angle) were used, and were performed before and immediately after PCI, and 18 month after the PCI.In our study, we showed that 5 of 7 patients who experienced PJF after PLIF did not receive any revision surgery after PCI. Immediately after cement injection, the anterior wedging rate (%) and the local kyphosis angle were significantly improved (P = .018, P = .028). The anterior wedging rates (%) and local kyphosis angle, at pre-PCI, immediate after PCI, and at final follow-up, were not significantly different between the non-revision surgery and revision surgery groups.Five of 7 patients who experienced PJF after PLIF did not receive revision surgery after PCI. Considering that general anesthesia and open surgery are high-risk procedures for geriatric patients, our results suggest that non-surgical PCI could be a viable alternative treatment option for PJF.SMC2017-01-011-001. Retrospectively registered 18 January 2017.

Diagnosis of internal derangement of the knee at 3.0-T MR imaging: 3D isotropic intermediate-weighted versus 2D sequences.

PURPOSE: To compare three-dimensional (3D) isotropic fast spin-echo (SE) intermediate-weighted magnetic resonance (MR) imaging with two-dimensional (2D) fast SE MR imaging-both performed at 3.0 T-for performance in the diagnosis of internal derangements of the knee. MATERIALS AND METHODS: The institutional review board approved this HIPAA-compliant study, and the requirement for informed consent was waived. The authors retrospectively reviewed 87 knee MR images obtained in 85 patients who had undergone both 3D isotropic and 2D MR examinations of the knee at 3.0 T and subsequent arthroscopic surgery. The 2D MR images included intermediate-weighted coronal and sagittal images, intermediate-weighted axial images with fat saturation, and T2-weighted sagittal images. The 3D isotropic MR images were obtained with multiplanar reformation (MPR), a fast SE intermediate-weighted sequence, and a reconstruction voxel size of 0.5 x 0.5 x 0.5 mm. Two radiologists retrospectively and independently evaluated the 2D and 3D data sets, at different sessions, for the presence of medial meniscus (MM), lateral meniscus (LM), anterior cruciate ligament (ACL), and posterior cruciate ligament (PCL) tears. These interpretations were compared with the arthroscopic surgery findings. The statistical differences between the sensitivities, specificities, and accuracies of the two methods were determined at McNemar testing, with surgical findings serving as the reference standard. Interobserver agreement was calculated by using kappa coefficients. RESULTS: For both reviewers, the sensitivity, specificity, and accuracy of both MR techniques were higher than 95% for the diagnosis of ACL and PCL tears, higher than 85% for the diagnosis of MM tears, and higher than 80% for the diagnosis of LM tears. There were no significant differences in sensitivity, specificity, or accuracy between the two methods. Interobserver agreement for evaluation of all lesions was excellent and ranged from 0.81 (LM tears evaluated with 3D and 2D sequences) to 0.93 (ACL tears evaluated with 3D and 2D sequences, PCL tears evaluated with 2D sequence, and MM tears evaluated with 3D sequence). CONCLUSION: The performance of 3D isotropic fast SE intermediate-weighted MR imaging with MPR was not significantly different from that of 2D MR imaging in the diagnosis of cruciate ligament and meniscal tears of the knee.

Three-dimensional isotropic shoulder MR arthrography: comparison with two-dimensional MR arthrography for the diagnosis of labral lesions at 3.0 T.

PURPOSE: To compare the diagnostic accuracy of three-dimensional (3D) isotropic magnetic resonance (MR) arthrography with two-dimensional (2D) MR arthrography for the diagnosis of labral lesions of the shoulder performed by using a 3.0-T imager. MATERIALS AND METHODS: Institutional review board approval was given for this retrospective study and informed consent was waived. From March 2006 to January 2007, 100 patients underwent 3D isotropic and 2D MR shoulder arthrographic imaging by using a 3.0-T imager and subsequent arthroscopic surgery. The 3D isotropic sequences were performed by using fast gradient-echo imaging with fat suppression (voxel size, 0.6 x 0.6 x 0.6 mm; imaging time, 5 minutes 32 seconds) and were evaluated for the presence of superior, anterior, and posterior labral lesions by using 3D isotropic and 2D MR arthrography. The statistical differences between the sensitivity and specificity for both methods were analyzed by using the McNemar test, with arthroscopic findings regarded as reference standard. RESULTS: Surgical findings confirmed 53 superior labral anterior posterior (SLAP) lesions, 17 anterior labral lesions, and five posterior labral lesions. Respective sensitivity and specificity were 85% and 96% for SLAP lesions, 100% and 98% for anterior labral lesions, and 80% and 99% for posterior labral lesions by using 2D MR arthrography and 83% and 96% for SLAP lesions, 100% and 96% for anterior labral lesions, and 80% and 99% for posterior labral lesions by using 3D isotropic MR arthrography. There was no significant difference in sensitivities and specificities of both methods; however, the power of this study was limited and larger comparison is needed. CONCLUSION: Isotropic 3D shoulder MR arthrography combined with a multiplanar reconstruction technique can help in the diagnosis of shoulder labral lesions as does 2D MR arthrography, but with shorter imaging times.

Comparison of indirect isotropic MR arthrography and conventional MR arthrography of labral lesions and rotator cuff tears: a prospective study.

OBJECTIVE: The purpose of our study was to prospectively compare the diagnostic accuracy of 3D isotropic indirect MR arthrography with conventional sequences of indirect MR arthrography for the diagnosis of labral and rotator cuff lesions on a 3-T MR unit. SUBJECTS AND METHODS: Thirty-six consecutive patients who were scheduled for shoulder arthroscopic surgery at our institution underwent indirect MR arthrography. Both conventional sequences and an additional 3D isotropic sequence were obtained 1 day before arthroscopic surgery. Two musculoskeletal radiologists prospectively evaluated the images in consensus for the presence of superior and anterior labral lesions and subscapularis and supraspinatus-infraspinatus tendon tears using the conventional sequences and the 3D isotropic sequence. We analyzed the statistical difference between the sensitivities and specificities of both methods using arthroscopic findings as the reference standard. RESULTS: Surgical findings confirmed the presence of 23 superior labral lesions, eight anterior labral lesions, 21 subscapularis tears, and 24 supraspinatus-infraspinatus tears. The sensitivity and specificity of the conventional sequences were 74% and 54% for superior labral lesions, 88% and 96% for anterior labral lesions, 67% and 85% for subscapularis tendon tears, and 96% and 75% for supraspinatus-infraspinatus tendon tears. The sensitivity and specificity of the 3D isotropic sequence were 70% and 85% for superior labral lesions, 100% and 100% for anterior labral lesions, 67% and 85% for subscapularis tendon tears, and 96% and 67% for supraspinatus-infraspinatus tendon tears. No statistically significant difference was seen in sensitivities and specificities for both methods. CONCLUSION: Three-dimensional isotropic MR arthrography sequences with multiplanar reconstruction can provide a similar capability for the diagnosis of labral and rotator cuff lesions as conventional MR arthrography sequences but in a shorter imaging time.

Initial experience with imaging-guided intramuscular botulinum toxin injection in patients with idiopathic cervical dystonia.

OBJECTIVE: The objective of our study was to present our initial experiences of imaging-guided intramuscular botulinum toxin (BTX) injection in patients with idiopathic cervical dystonia. CONCLUSION: Imaging-guided BTX injection is a useful treatment technique in patients with idiopathic cervical dystonia when target muscles are located deeply or an injection must be delivered to a focal muscle area.

Slot-scan digital radiography of the lower extremities: a comparison to computed radiography with respect to image quality and radiation dose.

OBJECTIVE: To compare the slot-scan digital radiography (SSDR) of the lower extremity region and the computed radiography (CR) method with respect to the image quality and radiation exposure. MATERIALS AND METHODS: We enrolled 54 patients who underwent both the SSDR and CR of the lower extremities. The study evaluated and statistically compared the image quality of four features (outer cortex, inner cortex, trabeculae and intermuscular fat) at six different levels (pelvis, hip, femur, knee, tibia and ankle) between each method. The image quality was evaluated using a visibility scale, and the entrance skin dose was measured using a dosimeter at three different levels of a phantom (hip, knee, and ankle). RESULTS: The mean image visibility scale values for the SSDR method were significantly higher than for the CR method. The entrance skin dose for the SSDR method was 278 microGy at each level, compared to the entrance skin doses of the CR method, which were 3,410 microGy for the hip, 1,152 microGy for the knee, and 580 microGy for the ankle. CONCLUSION: Both the image quality and patient entrance skin dose data suggest that the SSDR method is superior to the CR method for the lower extremity musculoskeletal examination.

Ankle morbidity after autogenous Achilles tendon harvesting for anterior cruciate ligament reconstruction.

Although several alternative autografts with reduced morbidity of harvest site have been introduced, no donor site is free of morbidity concerns. The authors report on ankle status after autogenous Achilles tendon harvesting with a minimum 10-year follow-up. From October 1994 to October 1996, a consecutive series of 47 ankles underwent harvesting of the medial third or half of the ipsilateral autogenous Achilles tendon for primary anterior cruciate ligament reconstruction. Donor site statuses were evaluated using a modified Thermann's scale. Postoperative isokinetic muscle strength testing was performed, and magnetic resonance images of donor sites were available for selected patients. Thirty-three ankles in the 32 patients were followed for more than 10 years. There were 27 men (84%) and 5 women (16%) with a mean age of 31 years (range 16-52 years) at the time of surgery. The mean duration of follow-up was 12 years and 1 month (range 10 years and 5 months to 13 years and 4 months). Mean postoperative modified Thermann's scale score was 87 (range 45-95; SD 14.3). Twenty-five (76%) ankles achieved very good or good results. A slight decrease in calf circumference <1 cm was seen in the ten ankles, 1-2 cm in the four ankles. Nine ankles were mildly hypersensitive to meteorological changes. Peak torque of ankle plantar flexion was slightly lower on the index limb at both velocities in nine selected patients who carried out performance tests. However, there were no significant differences (5.2% at 30 degrees /s and 2.7% at 120 degrees /s, P = n.s. and P = n.s.). Of the 12 available follow-up magnetic resonance images, the average cross-sectional area of the remaining tendon was 82.01 mm(2) (range 69.05-107.35; SD 10.3), and their average thickness was 7.4 mm (range 6-10.35; SD 1.1). After a minimum 10-year follow-up, the harvesting of autogenous Achilles tendons was not found to significantly jeopardize ankle status. However, it also could not be independent of donor morbidity as an alternative. The level of evidence was retrospective level IV, as a therapeutic study.

Pelvic bone complications after radiation therapy of uterine cervical cancer: evaluation with MRI.

OBJECTIVE: The purpose of this study was to assess the prevalence and distribution of radiation-induced insufficiency fractures and to investigate other bony complications of the female pelvis associated with radiation therapy using MR images. MATERIALS AND METHODS: Two radiologists retrospectively evaluated pelvic MR images of 510 patients (mean age, 54.7 years) who underwent pelvic irradiation for uterine cervical cancer for the presence and location of insufficiency fractures by consensus. We calculated the cumulative prevalence of pelvic insufficiency fractures on the basis of their results. In addition, we identified other associated bony complications of the female pelvis by reviewing the MR images. RESULTS: Insufficiency fractures were diagnosed in 100 patients; the 5-year cumulative prevalence was 45.2%. An insufficiency fracture was diagnosed a median of 16.9 months after radiation therapy. The fracture sites were the sacrum body and alae, medial side of the iliac bone, the roof of the acetabulum, superior rami of the pubic bone, femoral heads, and L5 vertebra. Sixty-one patients (61%) developed multiple fractures, and among them, 40 (40%) had bilateral symmetric lesions of the sacral alae. Other complications associated with the radiation therapy, as determined by evaluation of the MR images, were osteolysis and avascular necrosis of the femoral head. CONCLUSION: Radiation-induced pelvic insufficiency fractures are a frequent complication of radiation therapy for uterine cervical cancer. Osteolysis and avascular necrosis of the femoral head were also diagnosed using MRI after radiation therapy.

Comparison study of intraarticular and intravenous gadolinium-enhanced magnetic resonance imaging of cartilage in a canine model.

BACKGROUND: Magnetic resonance (MR) imaging and measurement of glycosaminoglycan (GAG) have potential for characterization of hyaline articular cartilage. Recently, some reports have demonstrated the potential of direct administration of contrast media for MR imaging of cartilage. PURPOSE: To prove the feasibility of intraarticular gadolinium-enhanced MR imaging of cartilage (iGEMRIC) and T1 relaxation mapping of the articular cartilage in vivo with intraarticular injection of Gd-DTPA2-. MATERIAL AND METHODS: Five healthy beagle dogs underwent MR imaging and T1 relaxation mapping of the knee joints of both hind legs. The delayed gadolinium-enhanced MR imaging of cartilage (dGEMRIC) and iGEMRIC techniques were interchanged with MR imaging. For dGEMRIC, a double routine dose of Gd-DTPA2- (0.2 mM/kg) was administered intravenously. For iGEMRIC, 2.5 and 1.25 mmol/l saline-diluted Gd-DTPA2- solutions were separately injected into the right and left knee joints, respectively, prior to MR imaging. Color-coded T1 maps of 20 femoral condyles were obtained from the dGEMRIC and iGEMRIC images. The signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and glycosaminoglycan (GAG) delineation of articular cartilage were compared between the dGEMRIC and iGEMRIC techniques. RESULTS: The mean SNR was higher with dGEMRIC than with iGEMRIC, but the difference was not statistically significant (P=0.174). The mean (+/-SD) CNR was higher with iGEMRIC (-11.6+/-3.4) than with dGEMRIC (-16.7+/-4.0; P=0.000), although the absolute value of the CNR was higher with dGEMRIC. The layering and gradient distribution of GAG were more clearly visualized on the iGEMRIC images. The mean scores of GAG delineation with dGEMRIC and iGEMRIC were 0.7+/-0.6 and 2.2+/-1.7, respectively. The iGEMRIC method better visualized GAG distribution (P=0.001). CONCLUSION: Although the SNR did not differ significantly between the iGEMRIC and dGEMRIC techniques, the color-coded T1 map produced with iGEMRIC allowed better cartilage evaluation. Thus, iGEMRIC exhibits the useful features of both MR arthrography and dGEMRIC, and provides a color-coded T1 map that is useful for diagnosing early articular cartilage damage.

Grading anterior cruciate ligament graft injury after ligament reconstruction surgery: diagnostic efficacy of oblique coronal MR imaging of the knee.

OBJECTIVE: The purpose of this study was to evaluate the diagnostic efficacy of using additional oblique coronal MRI of the knee for grading anterior cruciate ligament (ACL) graft injury after ligament reconstruction surgery. MATERIALS AND METHODS: We retrospectively reviewed 51 consecutive MR knee examinations of 48 patients who underwent both ACL reconstruction and follow-up arthroscopy. The MR examinations included the orthogonal axial, sagittal, coronal images and the oblique coronal T2-weighted images, which were oriented in parallel with the course of the femoral intercondylar roof. Two radiologists independently evaluated the status of the ACL grafts with using the routine knee MRI and then with adding the oblique coronal imaging. The severity of ACL graft injury was graded using a 3-point system from MR images as intact, partial tear or complete tear, and the results were compared with the arthroscopic results. Weighted kappa statistics were used to analyze the diagnostic accuracies of the knee MRI with and without the additional oblique coronal imaging. For each evaluation, the observers reported a confidence level for grading the ACL graft injuries in the two imaging groups. RESULTS: The weighted kappa values according to the routine knee MRI were 0.555 (reader 1) and 0.515 (reader 2). The inclusion of additional oblique coronal imaging increased the weighted kappa values to 0.666 (reader 1) and 0.611 (reader 2). The mean confidence levels by each reader were significantly higher (p < 0.01, paired t-test) with the additional oblique coronal imaging than by using the routine knee MRI alone. CONCLUSION: The additional use of oblique coronal MRI of the knee improves both the diagnostic accuracy and confidence for grading ACL graft injury.