The diagnostic value of magnetic resonance arthrography of the shoulder in detection and grading of SLAP lesions: comparison with arthroscopic findings

Purpose

The purpose of the study is to determine the usefulness of magnetic resonance arthrography (MRA) in diagnosis and grading of superior labrum anterior to posterior (SLAP) lesions of the Glenoid Labrum Compared with surgery

Material and methods

This was a prospective study including fifty nine clinically diagnosed SLAP patients. The study was done during the period from January 2008 to June 2010. All patients were submitted to history taking, clinical examination and conventional MRI examination of the shoulder, MRA was done in patients with negative conventional MRI, all of these patients underwent arthroscopy for diagnosis wither open or arthroscopy for diagnosis and treatment and results were compared with MRA findings.

Main outcome measures

Sensitivity, specificity, positive and negative predictive values, and overall accuracy of MR arthrography in detection and grading of SLAP lesions of the gelnoid labrum.

Results

Out of fifty nine patients, 25 patients had positive MR findings in conventional MRI, and 34 patients had negative MR findings, who underwent MR arthrography; 10 out of them had normal arthrogram (only 6 of them underwent arthroscopy), 22 had SLAP (superior labrum anterior to posterior) lesions, one had Bankart's lesion and one had internal impingement syndrome. These results were compared with arthroscopy results.The overall sensitivity of MRA in detection of SLAP lesions was 90% while the specificity was 50%, negative predictive value (NPV) was 66.6% and positive predicative value (PPV) was 81.8%. MRA and arthroscopy results were concurrent in 79.3% patients.

Conclusion

MR arthrography is a sensitive minimally invasive technique for detection and grading of SLAP lesions, it can help in avoiding patients unnecessary diagnostic arthroscopy.     

Inter- and intraobserver variability of MR arthrography in the detection and classification of superior labral anterior posterior (SLAP) lesions: evaluation in 78 cases with arthroscopic correlation

Purpose

The purpose of this study was to determine inter- and intraobserver variability of MR arthrography of the shoulder in the detection and classification of superior labral anterior posterior (SLAP) lesions.

Methods

MR arthrograms of 78 patients who underwent MR arthrography before arthroscopy were retrospectively analysed by three blinded readers for the presence and type of SLAP lesions. MR arthrograms were reviewed twice by each reader with a time interval of 4 months between the two readings. Inter- and intraobserver agreement for detection and classification of SLAP lesions were calculated using κ coefficients.

Results

Arthroscopy confirmed 48 SLAP lesions: type I (n?=?4), type II (n?=?37), type III (n?=?3), type IV (n?=?4). Sensitivity and specificity for detecting SLAP lesions with MR arthrography for each reader were 88.6%/93.3%, 90.9%/80.0% and 86.4%/76.7%. MR arthrographic and arthroscopic grading were concurrent for 72.7%, 68.2% and 70.5% of SLAP lesions for readers 1–3, respectively. Interobserver agreement was excellent (κ?=?0.82) for detection and substantial (κ?=?0.63) for classification of SLAP lesions. For each reader intraobserver agreement was excellent for detection (κ?=?0.93, κ?=?0.97, κ?=?0.97) and classification (κ?=?0.94, κ?=?0.84, κ?=?0.93) of SLAP lesions.

Conclusion

MR arthrography allows reliable and accurate detection of SLAP lesions. In addition, SLAP lesions can be diagnosed and classified with substantial to excellent inter- and intraobserver agreement.     

Conventional magnetic resonance imaging versus MR arthrography (MRA) of the wrist in the evaluation of triangular fibrocartilage lesions

Objective

The aim of this study is to assess the diagnostic value of direct MR arthrography compared to conventional MR imaging in the diagnosis of different pathologic entities affecting the triangular fibrocartilage.

Subjects and methods

This study included 51 patients complaining of chronic wrist pain. Conventional MRI and MR arthrography (MRA) was done for all cases.

Results

A comparison of the sensitivity of conventional MRI versus MRA was done by correlating the final diagnosis of each modality with the results of arthroscopy. MRI revealed a sensitivity (SEN) of 88.5%, specificity (SPE) of 100%, positive predictive value (PPV) of 100%, and a negative predictive value (NPV) of 69.2%, with an overall accuracy (ACC) of 90.9%, while MRA revealed a SEN of 94.2%, SPE of 100%, PPV of 100%, NPV of 81.8%, and ACC of 95.5%.

Conclusion

MR arthrography is a potent additional tool facilitating the diagnosis of different pathologic entities affecting the triangular fibrocartilage requiring surgical intervention and help to reduce arthroscopic interventions.     

Deep pelvic endometriosis: accuracy of pelvic MRI completed by MR colonography

Purpose

This study assessed the diagnostic accuracy of pelvic magnetic resonance (MR) imaging completed by MR colonography for the preoperative evaluation of deep pelvic endometriosis in patients undergoing laparoscopic surgery.

Materials and methods

A total of 143 patients (mean age 34.3±5.1 years) with a clinical suspicion of deep pelvic endometriosis were assessed by pelvic MR and MR colonography. All patients underwent laparoscopic surgery 3–10 weeks after the MR examination. The presence, location, number and extent of endometriotic lesions were evaluated. Data obtained with MR were compared with surgical findings. MR sensitivity, specificity, positive (PPV) and negative (NPV) predictive values and diagnostic accuracy values were calculated for each site by considering the laparoscopic and histological findings as the reference standard.

Results

Laparoscopy confirmed the presence of endometriosis in 119/143 patients (83%); in 76/119 (64%) deep pelvic endometriosis was diagnosed, whereas in the remaining 43/119 (36%), superficial peritoneal implants and endometriomas were found. In 32/119 (27%) patients, intestinal lesions were detected. MR had sensitivity, specificity, PPV, NPV and diagnostic accuracy values of 67–100%, 85–100%, 83–100%, 84–100% and 84–100%, respectively, in recognising lesions located in different pelvic sites.

Conslucions

MR imaging combined with colonography is a highly accurate tool for characterising deep endometriotic lesions in patients scheduled for laparoscopic surgery. In particular, MR colonography has very high accuracy in detecting colorectal involvement.     

Accuracy of 3-Tesla MR and MR arthrography in diagnosis of meniscal retear in the post-operative knee

Purpose

This study assesses the accuracy of 3-Tesla (3-T) conventional MR imaging, 3-T MR arthrography, and the combined use of conventional MR and MR arthrography in the diagnosis of meniscal retears as compared with arthroscopy. The study also assess whether there are false-negative cases in which injected contrast does not extend into the meniscus despite a meniscal retear being seen on arthroscopy.

Materials and methods

One hundred consecutive knee MR arthrograms performed on patients with previous knee surgery were reviewed retrospectively. 3-T conventional MR imaging, 3-T MR arthrography, and the combined use of conventional MR and MR arthrography were assessed for meniscal retears as compared with arthroscopy. The criterion used to diagnose a meniscal retear on MR arthrogram was injected contrast tracking into the meniscus. All patients underwent second-look arthroscopy.

Results

Seventy-four patients had conventional MR findings consistent with a meniscal retear. In 83 of the 100 patients, intraarticular contrast helped in demonstrating a retear. In ten patients, there were MR findings consistent with a meniscal retear despite intra-articular contrast not tracking into the meniscus. Ninety-four of the 100 patients had meniscal retears on second-look arthroscopy. Three-Tesla conventional MR examination was 78 % sensitive and 75 % specific, MR arthrogram examination was 88 % sensitive and 100 % specific, and the combined use of MR and MR arthrogram imaging was 98 % sensitive and 75 % specific in the diagnosis of a meniscal retear.

Conclusions

The combined use of 3-T MR and MR arthrography allows for high sensitivity and specificity in meniscal retear detection. In some patients, intraarticular contrast will not track into a meniscal retear. When MR findings are consistent with a meniscal retear but contrast does not extend into the meniscus, a meniscal retear is likely.     

3.0 T conventional hip MR and hip MR arthrography for the acetabular labral tears confirmed by arthroscopy

Objective

To evaluate the value of hip MR for diagnosing acetabular labrum tears, and to further compare the diagnostic performances of conventional MR with MR arthrography in acetabular labrum tears.

Methods

90 patients undergoing both hip MR examination and subsequent hip arthroscopy were retrospectively evaluated. Of these patients, 34 accepted both conventional MR and MR arthrography; while the other 56 only underwent conventional MR examination. All hip MR images were independently reviewed by two radiologists, and further compared with the results of hip arthroscopy.

Results

59 of 90 patients were confirmed with acetabular labral tears by hip arthroscopy and 31 without tears. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of conventional MR for evaluating the acetabular labral tears were 61.0%, 77.4%, 83.7% and 51.1% (radiologist A), and 66.1%, 74.2%, 82.9% and 53.4% (radiologist B), respectively, with good consistency between the two observers (K = 0.645). The sensitivity, specificity, PPV and NPV of MR arthrography for assessing the acetabular labral tears were 90.5%, 84.6%, 90.5% and 84.6% (radiologist A), and 95.2%, 84.6%, 90.9% and 91.7% (radiologist B), respectively, with excellent good consistency between the two observers (K = 0.810). The sensitivity and NPV of MR arthrography for diagnosing the acetabular labral tears were significantly higher than those of conventional MR (both P < 0.05).

Conclusion

Hip MR arthrography is a reliable evaluation modality for diagnosing the acetabular labral tears, and its diagnostic performance is superior to that of conventional MR at 3.0 T.     

Comparative study of direct MR arthrography and CT arthrography with arthroscopic correlation in preoperative evaluation of anterior shoulder instability

Purpose

To compare direct MR arthrography and CT arthrography for the preoperative planning of shoulder anterior instability.

Patients and methods

47 patients were included in this study. 43 patients with clinical history of anterior GHI or recurrent shoulder pain had no clinical findings of rotator cuff abnormality. They experienced multiple anterior dislocations of the shoulder. No patient showed evidence of multidirectional instability or generalized ligamentous laxity. The remaining 4 patients complained of anterior shoulder instability after anchor repair. All the patients underwent direct CT and MR arthrography. The results of CTA and MRA were compared with results obtained from arthroscopy in each patient to detect the sensitivity and specificity of each modality.

Results

The sensitivity and specificity of CTA for bankart lesion are 89.4% and 96.4% respectively and of MRA 94.7% and 96.4%, for Perthes lesion the sensitivity and specificity of CTA are 33.3% and 100% respectively and of MRA 66.6% and 100%, for ALPSA the sensitivity and specificity of CTA are 85.7% and 97.5% respectively and of MRA 100% and 97.5%, for GLAD the sensitivity and specificity of CTA are 80% and 97.6% respectively and of MRA 60% and 97.6%, for SLAP lesion the sensitivity and specificity of CTA are 100% and 100% respectively and of MRA 100% and 100%, for absent or degenerated labrum the sensitivity and specificity of CTA are 100% and 100% respectively and of MRA 66.6% and 97.7%, for post operative recurrent Bankart lesion the sensitivity and specificity of CTA are 100% and 100% respectively and of MRA 50% and 100%, for bony glenoid fracture the sensitivity and specificity of CTA are 100% and 100% respectively and of MRA 66.6% and 97.5%.

Conclusion

CTA and MRA were equivalent in demonstrating labro-ligamentous and cartilaginous lesions associated with shoulder instability. CTA was superior in detecting post operative instability and glenoid rim osseous lesions that are known to be a decisional element in the surgical strategy. Hence, CTA may be considered a method of choice in the preoperative evaluation of shoulder anterior instability.     

Comparison between multislice CT and MR imaging in the diagnostic evaluation of patients with pancreatic masses

Purpose

This study compared the results of multislice computed tomography (MSCT) and high-field magnetic resonance imaging (MRI) in the diagnostic evaluation of pancreatic masses.

Materials and methods

Forty patients with clinical and ultrasonographic evidence of pancreatic masses underwent MSCT and MRI. The majority of patients (31/40, 78%) had proven malignant pancreatic tumours (24 ductal adenocarcinoma, six mucinous cystadenocarcinoma, one intraductal papillary mucinous carcinoma), whereas the remaining patients (9/40, 22%) were found to have benign lesions (eight chronic pancreatitis, one serous cystadenoma). Results of the imaging studies were compared with biopsy (n=33) and/or histology (n=7) findings to calculate sensitivity, specificity, accuracy and positive (PPV) and negative (NPV) predictive value for correct identification of tumours and evaluation of resectability of malignancies.

Results

Both for tumour identification and resectability, MSCT and MRI had comparable diagnostic accuracy, with no statistically significant differences between them. Tumour identification CT/MRI: accuracy 98/98%, sensitivity 100/100%, specificity 88/88%, PPV 97/97%, NPV 100/100%; tumour resectability CT/MRI: accuracy 94/90%, sensitivity 92/88%, specificity 100/100%, PPV 100/100%, NPV 78/70%.

Conclusions

MRI represents a valid diagnostic alternative to CT in the evaluation of patients with pancreatic masses, both for correct identification and characterisation of primary lesions and to establish resectability in the case of malignancies. New high-field MRI equipment allows optimal imaging quality with good contrast resolution in evaluating the upper abdomen.     

Role of magnetic resonance imaging in probably benign (BI-RADS category 3) microcalcifications of the breast

Purpose

This study was undertaken to evaluate whether magnetic resonance (MR) imaging is able to rule out malignancy in the case of BI-RADS 3 microcalcifications, providing a sufficient negative predictive value (NPV) for early work-up, and to reduce unnecessary stereotactically guided vacuum-assisted biopsy (SVAB) procedures.

Materials and methods

We prospectively enrolled consecutive women with BI-RADS 3 microcalcifications, who subsequently underwent MR imaging and SVAB. The MR studies were reviewed according to the MR-BI-RADS classification system; lesions assessed as MR-BI-RADS 1 and 2 were considered negative for malignancy, categories MR-BI-RADS 3, 4 and 5 indicated malignant lesions. The presence of additional findings was recorded. Histologic analysis and follow-up were the reference standard. MR sensitivity, specificity, positive predictive value (PPV) and NPV were calculated.

Results

The final population consisted of 71 lesions. Histologic analysis showed malignancy in six cases (malignancy rate 8 %). At MR analysis, 60 (85 %) lesions were considered negative for malignancy and 11 (15 %) malignant. Additional MR imaging findings were identified in 19 (27 %) patients, all corresponding to nonmalignant lesions. MR sensitivity was 33 %, specificity 86 %, PPV 18 % and NPV 93 %.

Conclusions

Because of its relatively low NPV, MR imaging is not able to safely exclude malignancy in the case of BI-RADS 3 microcalcifications. The relatively high malignancy rate found in this study might support SVAB in the case of BI-RADS 3 microcalcifications.     

Indirect magnetic resonance arthrography of the shoulder; a reliable diagnostic tool for investigation of suspected labral pathology

Purpose

Indirect magnetic resonance arthrography (I-MRA) confers significant logistical advantages over direct MRA and does not require articular injection. In this study, we determined the diagnostic performance of I-MRA in relation to conventional MRI and arthroscopy or surgery in detecting tears of the glenoid labrum, including Bankart lesions and superior labral antero-posterior (SLAP) tears in a standard clinical setting.

Patients and methods

Ninety-one symptomatic patients underwent conventional MRI and I-MRA of the affected shoulder, followed by either arthroscopy or open surgery. The scans were interpreted independently by two experienced radiology consultants with a special interest in musculoskeletal radiology. Using the surgical findings as the standard of reference, sensitivity, specificity, and diagnostic accuracy of conventional non-contrast MRI and I-MRA in the detection of labral tears were calculated.

Results

The sensitivity of I-MRA was 95 and 97 %, respectively, for two radiologists as opposed to 79 and 83 % for conventional MRI. For both radiologists, the specificity of I-MRA, as well as MRI, was 91 % for detection of labral tears of all types. Accuracy of diagnosis was 93 and 95 %, respectively, for two radiologists with indirect MRA, compared to 84 and 86 % with non-contrast MRI.

Conclusions

This retrospective study shows that I-MRA is a highly accurate and sensitive method for the detection of labral tears. The data obtained supports the use of I-MRA as standard practice in patients with shoulder instability due to suspected labral pathology where further investigative imaging is indicated.     

Superior labrum anterior-posterior lesions: diagnosis with MR arthrography of the shoulder

PURPOSE: To determine the accuracy of magnetic resonance (MR) arthrography in the diagnosis of superior labrum anterior-posterior (SLAP) lesions of the shoulder. MATERIALS AND METHODS: From January 1995 to June 1998, MR arthrography of the shoulder was performed in 159 patients with a history of chronic shoulder pain or instability. Fifty-two patients underwent arthroscopy or open surgery 12 days to 5 months after MR arthrography. Diagnostic criteria for SLAP lesion included marked fraying of the articular aspect of the labrum, biceps anchor avulsion, inferiorly displaced bucket handle fragment, and extension of the tear into the biceps tendon fibers. Surgical findings were correlated with those from MR arthrography. RESULTS: SLAP injuries were diagnosed at surgery in 19 of the 52 patients (37%). Six of the 19 lesions (32%) were classified as type I, nine (47%) as type II, one (5%) as type III, and three (16%) as type IV. MR arthrography had a sensitivity of 89% (17 of 19 patients), a specificity of 91% (30 of 33 patients), and an accuracy of 90% (47 of 52 patients). The MR arthrographic classification showed correlation with the arthroscopic or surgical classification in 13 of 17 patients (76%) in whom SLAP lesions were diagnosed at MR arthrography. CONCLUSION: MR arthrography is a useful and accurate technique in the diagnosis of SLAP lesions of the shoulder. MR arthrography provides pertinent preoperative information with regard to the exact location of tears and grade of involvement of the biceps tendon.     

Intrinsic ligament and triangular fibrocartilage complex tears of the wrist: comparison of MDCT arthrography, conventional 3-T MRI, and MR arthrography

Purpose

This study compares the diagnostic performance of multidetector CT arthrography (CTA), conventional 3-T MR and MR arthrography (MRA) in detecting intrinsic ligament and triangular fibrocartilage complex (TFCC) tears of the wrist.

Materials and methods

Ten cadaveric wrists of five male subjects with an average age 49.6 years (range 26–59 years) were evaluated using CTA, conventional 3-T MR and MRA. We assessed the presence of scapholunate ligament (SLL), lunotriquetral ligament (LTL), and TFCC tears using a combination of conventional arthrography and arthroscopy as a gold standard. All images were evaluated in consensus by two musculoskeletal radiologists with sensitivity, specificity, and accuracy being calculated.

Results

Sensitivities/specificity/accuracy of CTA, conventional MRI, and MRA were 100 %/100 %/100 %, 66 %/86 %/80 %, 100 %/86 %/90 % for the detection of SLL tear, 100 %/80 %/90 %, 60 %/80 %/70 %, 100 %/80 %/90 % for the detection of LTL tear, and 100 %/100 %/100 %, 100 %/86 %/90 %, 100 %/100 %/100 % for the detection of TFCC tear. Overall CTA had the highest sensitivity, specificity, and accuracy among the three investigations while MRA performed better than conventional MR. CTA also had the highest sensitivity, specificity, and accuracy for identifying which component of the SLL and LTL was torn. Membranous tears of both SLL and LTL were better visualized than dorsal or volar tears on all three imaging modalities.

Conclusion

Both CT and MR arthrography have a very high degree of accuracy for diagnosing tears of the SLL, LTL, and TFCC with both being more accurate than conventional MR imaging.     

How often do surgeons intervene on shoulder labral lesions detected at MR examination? A retrospective review of MR examinations correlated with arthroscopy

Objective:

We report the prevalence of surgical intervention on shoulder labral lesions detected at MR examinations and how surgeons describe labral tears seen at MR examinations in their arthroscopy reports.

Methods:

A retrospective review of 100 consecutive patients aged 50 years or younger who had shoulder labral tears on MR and went on to have surgery performed. It was determined whether surgical intervention was performed on the MR lesions.

Results:

Of these 100 patients, 72 had superior labral anterior to posterior (SLAP) tears, 38 had posterior labral tears and 28 had anterior labral tears on MR examination. All 100 patients went on to arthroscopy. All lesions described on MRI were described on arthroscopy. Of the 72 SLAP tears, 64 were described as fraying on arthroscopy with 51 debrided. The remaining eight SLAP tears were tacked surgically. Of the 38 posterior labral tears, 36 were described as fraying on arthroscopy with 29 debrided and 2 had surgical tacking performed. Of the 28 anterior labral tears described on MR examination, 26 had surgical tacking performed and 2 were debrided. There were four SLAP tears, two anterior labral tears and three posterior labral tears seen on arthroscopy but not seen on MR examination.

Conclusion:

In this series, a high percentage of SLAP tears and posterior labral tears described on MR examination did not have surgical tacking. Most anterior labral tears had surgical tacking. Based on the above, our surgeons request we describe superior and posterior labral lesions as fraying and/or tearing, unless we can see a displaced tear. Most anterior labral lesions are treated with surgical tacking.

Advances in knowledge:

MRI allows for sensitive detection of labral tears. The tears often are not clinically significant.Labral tears are common injuries that often require surgical intervention. In our practice, we commonly see labral tears on MR examination and report them to surgeons. With modern high-resolution MRI, as well as increased awareness of labral tears by radiologists, labral tears are commonly reported findings on MR examinations. Sensitivities and specificities for detection of labral tears as compared with those from arthroscopy at 3.0 T have been reported as follows: superior labral anterior to posterior (SLAP) tears (90% sensitive and 100% specific), anterior labral tears (89% sensitive and 100% specific) and posterior labral tears (86% sensitivity and 100% specific).¹ Sensitivities of 100% for anterior labral tears, 86% for superior labral tears and 74% for posterior labral tears as compared with those from arthroscopy have been reported using high-resolution 1.5 T conventional MR examinations.²In our practice, we have been told by our surgeons that we describe some SLAP tears and posterior labral tears on MR that they find on arthroscopy to be degenerative fraying. For this reason, we sought to find (1) how often does a surgeon intervene on labral tears and (2) how do surgeons describe labral tears seen at MR examinations in their arthroscopy reports.     

3D-SPACE序列在肩关节MR造影中评估上盂唇前后撕裂

目的：评价肩关节 MR造影三维各向同性脂肪抑制快速自旋回波（SPACE）序列对上盂唇前后撕裂（SLAP损伤）的诊断价值。方法：影像诊断医师回顾性分析经关节镜证实的肩关节 MR 造影图像,判定有无SLAP 损伤及分型,对比常规二维序列和SPACE序列对SLAP损伤的敏感度、特异度及准确率,比较常规二维序列与SPACE 序列的诊断价值。结果：肩关节镜证实SLAP损伤12例,肩关节 MR造影SPACE序列与常规二维序列对SLAP 损伤的敏感度分别为83．33％（10/12）及91．67％（11/12）,特异度分别为81．25％（13/16）及87．50％（14/16）,准确度分别为82．14％（23/28）及89．29％（25/28）。SPACE序列与常规二维序列对 SLAP 损伤的诊断效能无明显统计学差异（P＞0．05）。结论：肩关节MR造影中SPACE序列是评价SLAP损伤准确、可靠的影像学方法。     

Comparison of 3.0-T MR vs 3.0-T MR arthrography of the hip for detection of acetabular labral tears and chondral defects in the same patient population

Objective:

We report our experience in diagnostic sensitivity of 3.0-T conventional MR vs 3.0-T MR arthrography of the hip for detection of acetabular labral tears and chondral defects in the same patient population.

Methods:

43 consecutive patients had both conventional hip MR and MR arthrography examinations performed. These examinations were reviewed retrospectively by independent reading of two musculoskeletal radiologists who read the MR and MR arthrogram examinations in a randomized fashion (i.e. MR and MR arthrogram examinations were read at separate sittings and in a randomized fashion so as not to bias reviewers). Scans were assessed for acetabular labral tears and chondral defects. All patients went on to arthroscopy.

Results:

Of these 43 patients, 40 had acetabular labral tears read by Reader 1 and 39 had acetabular labral tears read by Reader 2 on MR arthrogram, 39 had acetabular labral tears read by Reader 1 and 38 had acetabular labral tears read by Reader 2 on conventional MR examination. There were 42 labral tears in 43 patients at arthroscopy. There were four false-negative labral tears compared with arthroscopy on MR and three false negatives on MR arthrography for Reader 1 and five false negatives on MR and four false negatives on MR arthrography for Reader 2. Each reader had one false-positive labral tear compared with arthroscopy on both MR and MR arthrography. There were 32 acetabular chondral defects at arthroscopy. Reader 1 saw 21 acetabular chondral defects on conventional MR and 27 chondral defects at MR arthrography. Reader 2 saw 19 acetabular chondral defects at conventional MR and 25 acetabular chondral defects on MR arthrography. There were no false-positive readings of chondral defects compared with arthroscopy on MR and one false positive for Reader 1 and two false positives for Reader 2 on MR arthrography as compared with arthroscopy. On conventional MR examination, sensitivities and specificities as compared with arthroscopy were as follows: Reader 1 acetabular labral tear (90% sensitivity, 0% specificity) and Reader 2 acetabular labral tear (88% sensitivity, 0% sensitivity). On MR arthrogram, sensitivities and specificities as compared with arthroscopy for Reader 1 were 93%, 0% and for Reader 2 were 90%, 0%, respectively. Sensitivities and specificities for detection of acetabular chondral defects as compared with arthroscopy were Reader 1 conventional MR (65% sensitivity, 100% specificity), Reader 1 MR arthrography (81% sensitivity, 91% specificity), Reader 2 conventional MR (59% sensitivity, 100% specificity) and Reader 2 MR arthrography (71% sensitivity, 82% specificity).

Conclusion:

In this series, 3.0-T MR demonstrated sensitivity for detection of acetabular labral tears that rivals the sensitivity of 3.0-T MR arthrography of the hip. In this series, 3.0-T MR arthrography was more sensitive than conventional 3.0-T MR for detection of acetabular chondral defects.

Advances in knowledge:

3.0-T MR and MR arthrography are near equivalent in the diagnosis of acetabular labral tears. This information is useful for pre-operative planning.MR arthrography has been reported to be more sensitive and specific for detection of acetabular labral tears in the hip than conventional MRI.^1–10 MR arthrography has also been reported to be superior in detection of acetabular cartilage defects as compared with conventional MRI.¹¹ To our knowledge 3.0-T MR vs 3.0-T MR arthrography sensitivity for detection of acetabular labral tears and chondral defects has not been specifically assessed.To our knowledge, Petersilge et al¹ first reported the utility of hip MR arthrography in the diagnosis of acetabular labral tears. Toomayan et al² compared MR arthrography of the hip with conventional MRI of the hip in different patient populations. He found MR arthrography with a small field of view to be substantially more sensitive for detection of acetabular labral tears than conventional MRI. Sutter et al¹¹ found 1.5 T MR arthrography to be superior to conventional MRI for detecting labral tears and acetabular cartilage defects.Patients with acetabular labral tears present with symptoms of persistent pain, clicking, locking and decreased range of motion. With the availability of hip arthroscopy, labral tears can more easily be addressed with minimally invasive surgery. Accurate pre-operative identification of labral tears is needed.² Based on previous studies demonstrating the accuracy of MR arthrography in detection of acetabular labral tears, surgeons often request MR arthrography of the hip to characterize labral tears prior to surgery.^1–10 The purpose of this study is to assess 3.0-T MR vs MR arthrography diagnostic performance in detection of acetabular labral tears and chondral defects in the same patient population using arthroscopy as a reference standard.     

MR-PET fusion imaging in evaluating adnexal lesions: a preliminary study

Purpose

The objective of this preliminary study was to examine the effects of combined magnetic resonance/positron emission tomography (MR-PET) evaluation in the morphofunctional characterisation of ovarian lesions.

Materials and methods

From June 2008 to September 2010, we evaluated 24 patients (mean age 44±10 years; range 24?C74) with ovarian lesions incidentally detected on ultrasonography (US) and/or multislice computed tomography (CT). All patients underwent MR imaging of the pelvis and total-body CT-PET. PET and MR images were subsequently fused at postprocessing using specific anatomical criteria. Results were compared with the histological examination.

Results

Of the 24 examined lesions, 19 were malignant and five were benign on histological examination. MR, CT-PET and MR-PET sensitivity was 84%, 74% and 94%, respectively and specificity 60%, 80% and 100%, respectively. Positive (PPV) and negative predictive (NPV) values were 93% and 44% for CT-PET, 89% and 50% for MR and 100% and 83% for MR-PET, respectively.

Conclusions

Pelvic MR-PET fusion imaging provides advantages in terms of sensitivity and especially specificity compared with MR imaging or CT-PET alone. The added value of this fusion imaging modality lies in combining the benefits of the morphological evaluation provided by MR imaging and the metabolic assessment provided by PET.     

Diagnosis of SLAP lesions with Grashey-view arthrography

OBJECTIVE: To examine the accuracy of Grashey views obtained during shoulder arthrography in the diagnosis of clinically relevant superior labrum anterior-posterior (SLAP) lesions. DESIGN AND PATIENTS: Grashey views obtained during diagnostic arthrography (conventional and MR) were used to examine the superior labrum. Twenty-eight of 118 shoulder arthrograms obtained during a 27-month period fulfilled study criteria and were correlated for accuracy using arthroscopically confirmed grade 2-4 SLAP lesions as the standard of reference. Arthrograms were graded using the consensus method. Prevalence, sensitivity, specificity, and accuracy were 21%, 50%, 86%, and 79%. The appearance of the superior labrum on the Grashey view was compared subjectively with MR arthrography. Sources of errors were analyzed. CONCLUSION: Grashey views obtained during shoulder arthrography can diagnose clinically relevant SLAP lesions with moderately high specificity, moderate accuracy, and limited sensitivity. Findings on the Grashey view closely resemble those seen on coronal oblique MR arthrography. Grashey views should be considered in patients undergoing shoulder arthrography.     

上方盂唇前后向撕裂的肩关节MR造影评价

目的 评价肩关节MR造影对上方盂唇前后向撕裂(SLAP损伤)的诊断价值.方法 由2名影像诊断医师独立回顾分析137例经肩关节镜证实的肩关节造影MR图像,判定有无SLAP损伤,并进行分型.SLAP损伤分4型:Ⅰ型为上盂唇毛糙,Ⅱ型为肱二头肌腱盂唇复合体从关节孟撕裂,Ⅲ型为上盂唇桶柄状撕裂,Ⅳ型为上盂唇桶柄状撕裂并同时累及肱二头肌长头腱.计算肩关节MR造影对SLAP损伤的敏感度、特异度和准确度,以及与肩关节镜分型的符合率.采用Kappa统计计算2名影像诊断医师评价的一致性.结果 137例患者中,肩关节镜证实SLAP损伤59例,包括SLAP损伤Ⅰ型6例(10.2%)、Ⅱ型50例(84.7%)、Ⅲ型3例(5.1%).肩关节MR造影的敏感度、特异度和准确度医师甲分别为86.4%(51/59)、78.2%(61/78)和81.8%(112/137),医师乙分别为88.1%(52/59)、84.6%(66/78)和86.1%(118/137).2名影像诊断医师的评价一致性极好(K=0.796).肩关节MR造影与肩关节镜的分型符合率医师甲为83.1%(49/59),医师乙为79.7%(47/59).结论 肩关节MR造影是评价SLAP损伤比较可靠的影像方法.     

Conventional MR in rotator cuff pathology. Is it sufficient?

Background

Magnetic resonance (MR) provides detailed information for the depiction of shoulder lesions. It allows a unique anatomical and tissue characterization providing a detailed evaluation of the rotator cuff (RC) and the surrounding bones.

Accuracy of chemical shift MR imaging in diagnosing indeterminate bone marrow lesions in the pelvis: review of a single institution’s experience

Objective

To re-assess the accuracy of chemical shift imaging in diagnosing indeterminate bone marrow lesions as benign or malignant.

Materials and methods

We retrospectively reviewed our experience with MR imaging of the pelvis to assess the accuracy of chemical shift imaging in distinguishing benign from malignant bone lesions. Two musculoskeletal radiologists retrospectively reviewed all osseous lesions biopsied since 2006, when chemical shift imaging was added to our routine pelvic imaging protocol. Study inclusion criteria required (1) MR imaging of an indeterminate bone marrow lesion about the pelvis and (2) subsequent histologic confirmation. The study group included 50 patients (29 male, 21 female) with an average age of 67 years (range, 41–89 years). MR imaging results were evaluated using biopsy results as the “gold standard.”

Results

There were 27 malignant and 23 benign lesions. Chemical shift imaging using an opposed-phase signal loss criteria of less than 20 % to indicate a malignant lesion, correctly diagnosed 27/27 malignant lesions and 14/23 benign lesions, yielding a 100 % sensitivity, 61 % specificity, 75 % PPV, 100 % NPV, and 82 % accuracy. The area under the receiver operator characteristic (ROC) curve was 0.88. The inter-rater and intra-rater agreement K values were both 1.0.

Conclusions

Chemical shift imaging is a useful adjunct MR technique to characterize focal and diffuse marrow abnormalities on routine non-contrast pelvic imaging. It is highly sensitive in identifying malignant disease. Despite its lower specificity, the need for biopsy could be eliminated in more than 60 % of patients with benign disease.