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T R McCauley

Publications and source records attributed to T R McCauley.

At least 19 recordsLinked to original sources
PubMed2001

Clinical imaging of articular cartilage in the knee.

Assessment of articular cartilage has become an essential part of magnetic resonance (MR) evaluation of the knee. This has occurred because of recent advances in treatment along with improved accuracy of MR image evaluation of articular cartilage. Detection of articular cartilage defects can provide an explanation for symptoms and allow identification of patients for cartilage therapy and is an important factor for predicting prognosis of patients with knee injury. This review describes the most easily implemented MR techniques for evaluation of articular cartilage and the normal and abnormal appearance of cartilage seen using these techniques. The influence of imaging findings on treatment is described.

Cartilage, Articular↗
PubMed2001

Superior labral anterior posterior (SLAP) lesions of the glenoid labrum: reliability and accuracy of MR arthrography for diagnosis.

PURPOSE: To determine the reliability and accuracy of magnetic resonance (MR) arthrography for the diagnosis of superior labral anterior posterior (SLAP) tears. MATERIALS AND METHODS: The MR arthrograms in 80 patients who underwent arthroscopy and MR arthrography during a 54-month period were retrospectively reviewed. MR arthrograms were independently scored by three observers for the presence and type of SLAP lesion. Type I SLAP lesions were regarded as negative as they most often are not clinically relevant. Interobserver agreement for detection of SLAP lesions was calculated by using kappa coefficients. The differences in areas under the receiver operating characteristic (ROC) curves were assessed with a univariate z score test. RESULTS: At arthroscopy, there were 25 SLAP tears: type II (n = 22), type III (n = 2), and type IV (n = 1). Sensitivity, specificity, and accuracy of each reader were 92%, 84%, and 86%; 92%, 82%, and 85%; and 84%, 69%, and 74%, respectively. Interobserver agreement for SLAP tears was substantial (kappa = 0.77) to moderate (kappa = 0.52, kappa = 0.44). The areas under the ROC curves for each reader were 0.94, 0.93, and 0.83, which were not significantly different. CONCLUSION: MR arthrography of the shoulder is reliable and accurate for detection of SLAP tears.

Adolescent↗
PubMed2001

Central osteophytes in the knee: prevalence and association with cartilage defects on MR imaging.

OBJECTIVE: The objective of this study was to determine the prevalence and location of central osteophytes in patients referred for MR imaging of the knee and the relationship of central osteophytes to articular cartilage defects, marginal osteophytes, meniscal tears, and anterior cruciate ligament tears as seen on MR imaging. MATERIALS AND METHODS: Two hundred consecutive patients referred for MR imaging of the knee were evaluated for central osteophytes, articular cartilage defects, marginal osteophytes, meniscal tears, and anterior cruciate ligament tears. A 1.5-T scanner was used, and assessments were made by consensus of two experienced musculoskeletal radiologists. Seven patients were excluded, leaving 193 patients in the study population. RESULTS: The prevalence of central osteophytes in the knee was 15% (35 central osteophytes in 29 patients). Patients with central osteophytes were older (mean age, 52 years versus 38 years), weighed more (mean weight, 204 lb [92 kg] versus 174 lb [78 kg]), had more articular cartilage defects (mean, 4.3 versus 1.3), and had more marginal osteophytes (mean, 3.9 versus 1.1) than patients without central osteophytes (p < 0.0001, Student's t test). Patients with central osteophytes were more likely to have a meniscal tear (p = 0.004, chi-square test), but they were not more likely to have an anterior cruciate ligament tear. All central osteophytes were associated with articular cartilage defects at the same location, which were full or near-full thickness on MR imaging for 32 of 35 central osteophytes. CONCLUSION: Central osteophytes are common in patients referred for MR imaging of the knee. When central osteophytes are seen in the knee there is a high likelihood of an associated full thickness or near-full thickness articular cartilage defect.

Adult↗
PubMed2000

MR imaging of articular cartilage.

With the advent of new treatments for articular cartilage disorders, accurate noninvasive assessment of articular cartilage, particularly with MR imaging, has become important. Understanding the MR imaging features of articular cartilage has led to the development of two types of routinely available MR imaging techniques which have demonstrated clinical accuracy and interobserver reliability.

Artifacts↗
PubMed2000

Bone marrow edema in the greater tuberosity of the humerus at MR imaging: association with rotator cuff tears and traumatic injury.

UNLABELLED: The purpose of this study was to determine the prevalence of bone marrow edema in the greater tuberosity of the humerus on MR imaging, the association with other findings at MR imaging and the injury mechanism which can lead to this finding. SUBJECTS AND METHODS: MR reports from 863 patients referred for shoulder MRI over 74 months were reviewed to identify patients with marrow edema in the greater tuberosity. The MR images from patients with greater tuberosity marrow edema were reviewed by consensus of two radiologists for the extent of marrow edema and for associated injuries. Marrow edema in the greater tuberosity was seen in 11 of 863 patients (1.3%). Nine patients (82%) had associated rotator cuff tear by MR imaging (four full thickness and five partial thickness), one patient had avulsion of the greater tuberosity from the humerus, and one had no rotator cuff abnormality. History of trauma was reported by eight patients including fall without direct blow to the shoulder (6), car accident (1) and direct blow to the top of the shoulder (1). Marrow edema in the greater tuberosity is an infrequent finding. Marrow edema most often is associated with a history of trauma and with rotator cuff abnormalities including full thickness tears. The history of trauma without direct blow to the shoulder and the location of the edema indicates that marrow edema often results from avulsion injury by the supraspinatus tendon.

Adult↗
PubMed2000

Articular cartilage defects: in vitro evaluation of accuracy and interobserver reliability for detection and grading with US.

PURPOSE: To determine the accuracy and reliability of detecting and grading articular cartilage defects in porcine and human knees by using ultrasonography (US). MATERIALS AND METHODS: US was used to evaluate 175 porcine and 16 human knee surfaces with a linear 5-12-MHz transducer. Porcine defects of varying diameter and depth were surgically created. Each porcine surface was independently assessed in blinded fashion by two radiologists for the presence and severity of defects. Accuracy of detection, interobserver reliability, and concordance between US and surgical grades were determined. Human specimens were retrieved from knees of patients who underwent joint arthroplasty. Defects in human knees detected with US were correlated with defects seen at direct surface visualization. RESULTS: Sensitivities for detection of porcine defects were 94% and 93% for readers 1 and 2, respectively; specificities were 90% and 77%, respectively; positive predictive values were 98% and 95%, respectively; and negative predictive values were 78% and 73%, respectively. Interobserver agreement was high (weighted kappa = 0.80), and concordance between US and surgical grades for both readers was high (weighted kappa = 0.90 and 0.78). In human cartilage, the distribution of cartilage denudation determined at US was the same as that determined at direct visualization. CONCLUSION: High-frequency US was accurate and reliable for detection and grading of knee articular cartilage defects.

Animals↗
PubMed1998

Internal derangements of the knee: rates of occurrence at MR imaging in patients referred by orthopedic surgeons compared with rates in patients referred by physicians who are not orthopedic surgeons.

PURPOSE: To compare the occurrence at magnetic resonance (MR) imaging of clinically important knee abnormalities in patients referred by orthopedic surgeons with that in patients referred by other physicians. MATERIALS AND METHODS: Knee MR images in all patients referred for evaluation of internal derangement for 12 months were retrospectively reviewed. Meniscus, ligament, and articular cartilage abnormalities were tabulated. The numbers of abnormalities detected in the patients referred by orthopedic surgeons were compared with those in the patients referred by all other physicians by using chi(2) analysis. Significance was defined at P less than .05. RESULTS: Knee MR images in 439 patients were reviewed; 328 patients were referred by orthopedic surgeons, and 111 were referred by other physicians. There was no significant difference in the rates of occurrence of meniscus tear (149 [45%; orthopedic surgeon referrals] vs 50 [45%; other physician referrals], P = .96); ligament tear (82 [25%] vs 21 [19%], P = .25); isolated hyaline cartilage defect (77 [23%] vs 20 [18%], P = .29); meniscus or ligament tear (167 [51%] vs 55 [50%], P = .86); or meniscus, ligament, or articular cartilage tear (242 [74%] vs 72 [65%], P = .34). The proportion of patients who subsequently underwent surgery of the knee was also similar (39% [118 of 300] vs 28% [23 of 82], P = .14). CONCLUSION: There was no significant difference in the occurrences of clinically important knee internal derangement at MR imaging between patients referred by orthopedic surgeons and those referred by other physicians.

Adolescent↗
PubMed1998

Clinical magnetic resonance imaging of articular cartilage.

Magnetic resonance (MR) imaging of articular cartilage has recently become of intense interest because of new developments in the treatment of articular cartilage injury. Recent advances in MR imaging technology has allowed the development of imaging sequences tailored to the assessment of articular cartilage. Several clinical studies have validated the accuracy and reliability of high-resolution, fat-suppressed, three-dimensional, spoiled gradient-recalled MR imaging in the assessment of articular cartilage defects of the knee. The use of other MR imaging techniques is evolving, including the use of fast spin-echo imaging and anionic contrast-enhanced T1-weighted imaging. This article describes the background and rationale to MR imaging of articular cartilage and focuses on its clinical application. Because the knee has been the focus of most research in articular cartilage imaging, the discussion in this article will be largely restricted to this joint.

Cartilage, Articular↗
PubMed1997

Rotator cuff: evaluation with fast spin-echo versus conventional spin-echo MR imaging.

PURPOSE: To determine if fast spin-echo (SE) magnetic resonance (MR) imaging can provide similar information to that of conventional SE imaging for evaluation of the rotator cuff. MATERIALS AND METHODS: One hundred twenty-six patients underwent MR imaging with conventional SE and non-fat-suppressed fast SE sequences (65 patients) or conventional SE and fat-suppressed fast SE sequences (61 patients). Two radiologists independently graded the rotator cuff with separate and side-by-side assessment of the fast SE and conventional SE images. RESULTS: For detection of full-thickness tears, agreement between non-fat-suppressed fast SE and conventional SE images was 93.8% (kappa = 0.78 [good]) and 95.4% (kappa = 0.82 [very good]) for the two readers, respectively, and agreement between fat-suppressed fast SE and conventional SE images was 98.4% (kappa = 0.96 [very good]) and 91.8% (kappa = 0.73 [good]) for the two readers, respectively. Rotator cuff grading was similar for fast SE and conventional SE: weighted kappa = 0.77 (good) and 0.68 (good) for non-fat-suppressed and weighted kappa = 0.83 (very good) and 0.67 (good) for fat-suppressed fast SE images for the two readers, respectively. CONCLUSION: Fast SE sequences yield similar interpretations as those obtained with a conventional SE sequence for evaluation of the rotator cuff.

Adolescent↗
PubMed1997

Effect of hydration status on renal medulla attenuation on unenhanced CT scans.

OBJECTIVE: The purpose of this study was to assess the effect of hydration status on renal medulla attenuation during unenhanced CT. SUBJECTS AND METHODS: An unenhanced CT scan was obtained in 10 healthy men after 12-18 hr of complete fluid restriction and again after rehydration. CT images were reviewed for the presence and extent of dense renal medulla, defined as greater attenuation than the adjacent cortex. CT findings were correlated with urine-specific gravity and osmolality. RESULTS: Eight of the 10 subjects showed dense renal medulla on a CT scan after dehydration. After rehydration, complete resolution was seen on the CT scan in four of the eight subjects; three of the eight subjects showed a decrease in the extent of dense renal medulla. After rehydration, the eighth subject showed a slight increase in the attenuation of the renal medulla on the CT scan. Dense renal medulla was seen significantly more often on dehydration images (p = .035). CONCLUSION: Increased renal medulla attenuation on an unenhanced CT scan can be a normal finding related to dehydration.

Adult↗
PubMed1997

In-phase and out-of-phase MR imaging of bone marrow: prediction of neoplasia based on the detection of coexistent fat and water.

OBJECTIVE: The purpose of this study was to determine if gradient-echo MR imaging with TEs selected with fat and water in phase and out of phase can help predict the likelihood of neoplastic or nonneoplastic lesions in bone marrow. SUBJECTS AND METHODS: Thirty consecutive patients with 31 suspected bone marrow lesions underwent MR imaging, including two spoiled gradient-echo sequences identical in all parameters except TE, which was chosen such that fat and water were either in phase or out of phase. Relative ratios of the abnormal bone marrow signal intensity and a control site on the in-phase and out-of-phase images were expressed. The images were also assessed independently by two reviewers who were unaware of the patients' identities and clinical histories. Reviewers assessed decreased marrow signal intensity relative to control sites on the out-of-phase and in-phase images. Pathologic confirmation was obtained in 16 patients (17 lesions); the remainder of patients had either established diagnoses or determination of benignity based on stability of findings at 1 year. Relative ratios were compared with the Student's t test and receiver operating characteristic (ROC) curve analysis, and the reviewers' scores were evaluated with ROC curve analysis. RESULTS: The relative signal-intensity ratios were 1.03 +/- 0.13 for the neoplastic group and 0.62 +/- 0.13 for the nonneoplastic group (p < .0001). ROC curve analysis of the signal-intensity ratios showed a z-score of .99. A ratio cutoff value of 0.81 resulted in a 95% sensitivity and a 95% specificity for detection of neoplasm. Both reviewers achieved 100% sensitivity and 94-100% specificity for detection of neoplasms. CONCLUSION: In-phase and out-of-phase gradient-echo MR imaging of bone marrow signal-intensity abnormalities can help predict the likelihood of neoplastic or nonneoplastic lesions.

Bone Marrow↗
PubMed1996

Volumetric flow estimation in vivo and in vitro using pulsed-Doppler ultrasound.

The measurement of volumetric blood flow in small vessels in vitro and in vivo poses a significant technological challenge. In this study, two pulsatile flow models were developed, one with a 3.2-mm lumen diameter and one with a 12.7-mm lumen diameter, to assess the accuracy of volumetric flow estimation of two pulsed-Doppler devices, a Crystal Biotech VF1 20-MHz system with either a cuff-mounted or a needle-mounted probe and an Advanced Technology Laboratories Ultramark 9 High Definition Imaging system with a 5-MHz linear array transducer. The VF1 volumetric flow error was measured in the 3.2-mm phantom over a variety of pulsatile and continuous waveforms. The accuracy of the VF1 was also tested in porcine femoral and renal arteries. VF1 volumetric flow error ranged from 4.8% to 54.3% in the in vivo studies. The ATL demonstrated similar volumetric flow errors in the porcine femoral artery (approximately 3.2 mm diameter), but these errors were reduced to < or = 17.4% in the 12.7-mm-diameter in vitro flow model.

Animals↗
PubMed1996

Articular cartilage volume in the knee: semiautomated determination from three-dimensional reformations of MR images.

PURPOSE: To determine the accuracy of semiautomated quantification of articular cartilage volume from three-dimensional (3D) reformations of magnetic resonance (MR) images. MATERIALS AND METHODS: Sagittal, fat-suppressed, 3D, spoiled gradient-recalled-echo MR imaging of two bovine and two human cadaver knees was performed. Articular cartilage volume was calculated from 3D reformations of the MR images by using a semiautomated program written at the authors' institution. Calculated volumes were compared with directly measured volumes of the surgically removed articular cartilage. RESULTS: The percentage of error of the MR imaging-determined volumes was 6.53% +/- 4.75 (mean +/- standard deviation). A strong correlation between the two sets of observations was shown (r=.997). Linear regression showed the calculated volumes to be highly accurate (slope=1.002, P>.25). Repeated reformations yielded volumes that were reproducible (mean absolute error, 0.013 mL +/- 0.019) and not significantly different from the measured volume (P>.10). CONCLUSION: Semiautomated quantification of knee articular cartilage from MR images yields highly accurate cartilage volumes.

Animals↗
PubMed1996

Fat-suppressed three-dimensional spoiled gradient-echo MR imaging of hyaline cartilage defects in the knee: comparison with standard MR imaging and arthroscopy.

OBJECTIVE: The sensitivity of fat-suppressed three-dimensional spoiled gradient-echo (SPGR) images was compared with that of standard MR images for detecting hyaline cartilage defects of the knee, using arthroscopy as the standard of reference. SUBJECTS AND METHODS: We assessed 114 consecutive patients for hyaline cartilage defects of the knee with both standard MR imaging sequences and a sagittal fat-suppressed three-dimensional SPGR sequence. Of these patients, 48 with meniscal or ligament injury, or persistent symptoms, underwent subsequent arthroscopy. The standard MR images and SPGR images of these 48 patients were then retrospectively analyzed for articular defects in a blinded fashion by two independent observers. Sensitivity, specificity, and intraobserver and interobserver agreement were determined for the different imaging techniques. RESULTS: One fourth of the patients who went on to arthroscopy were shown to have isolated hyaline cartilage lesions that were clinically confused with meniscal tears and that were missed on the standard MR images. When looking at all surfaces combined for each reader, the SPGR imaging sequence had a significantly higher sensitivity than the standard MR imaging sequences for detecting hyaline cartilage defects (75-85% versus 29-38%, p < .001 for each comparison). When looking at individual surfaces for each reader, significant differences in sensitivity were shown for each surface except the trochlear and lateral tibial surfaces. We found no difference in specificity (97% versus 97%, p > .99). We also found that combined evaluation of standard MR and SPGR images gave no added diagnostic advantage (sensitivity, 86%; specificity, 97%; p > .42). Except for the lateral tibial surface, the study achieved excellent reproducibility among readings and between readers. CONCLUSION: Fat-suppressed three-dimensional SPGR imaging is more sensitive than standard MR imaging for the detection of hyaline cartilage defects of the knee.

Adolescent↗
PubMed1996

Quantitative blood flow measurements with cine phase-contrast MR imaging of subjects at rest and after exercise to assess peripheral vascular disease.

OBJECTIVE: The purpose of this study was to determine whether cine phase-contrast MR volume flow measurements can identify patients with peripheral vascular disease. SUBJECTS AND METHODS: We performed MR measurements of volume blood flow in the popliteal artery of subjects at rest and after 5 min of plantar flexion exercise in 10 volunteers (mean age, 28 years old), in five patients suspected of having peripheral vascular disease (mean age, 58 years old), and in five other volunteers of a similar age (mean age, 57 years old). RESULTS: Volume blood flow at rest was similar in volunteers and in patients. Four patients who had abnormal ankle-brachial indexes had lower flow increases after exercise (2.6-fold) compared with the five older normal volunteers (4.8-fold; p < .03, t test). These flow increases correlated well with ankle-brachial indexes: r = .97. The four patients with abnormal ankle-brachial indexes had monophasic resting waveforms, whereas all other subjects had triphasic waveforms. CONCLUSION: MR volume blood flow measurement may aid in evaluating peripheral vascular disease. Studies of larger patient groups will be necessary.

Adult↗
PubMed1995

Detection of knee hyaline cartilage defects using fat-suppressed three-dimensional spoiled gradient-echo MR imaging: comparison with standard MR imaging and correlation with arthroscopy.

OBJECTIVE: A preliminary study was done to prospectively compare fat-suppressed three-dimensional spoiled gradient-echo (3D SPGR) MR imaging with standard MR imaging for detection of defects in the hyaline cartilage of the knee, using arthroscopy as the reference standard. SUBJECTS AND METHODS: We studied 43 consecutive patients referred by two orthopedic surgeons for MR imaging of the knee. Twelve had arthroscopic correlation; they formed the basis of our study. Hyaline cartilage was imaged with a fat-suppressed 3D SPGR sequence with previously determined optimal imaging parameters. Our standard MR imaging study consisted of two-dimensional coronal T1-weighted spin-echo, sagittal dual-echo T2-weighted spin-echo, and axial multiplanar gradient-echo sequences. With arthroscopy as the reference standard, sensitivity and specificity of fat-suppressed 3D SPGR and standard MR images for detecting cartilage tears were determined by articular surface (eight surfaces in each patient: medial and lateral patellar facets, trochlear facets, femoral condyles, and tibial plateaus). Statistically significant differences in sensitivity and specificity were determined. RESULTS: Arthroscopy showed 15 cartilage defects in seven patients. The fat-suppressed 3D SPGR images had higher sensitivity (93%) than the standard MR images (53%, p = .03). Specificity was 94% for the fat-suppressed 3D SPGR images compared with 93% for the standard MR images (p > .05). The five false-positive articular surfaces on fat-suppressed 3D SPGR images were from focal signal change within the substance of the cartilage without a contour defect. Smoothly contoured thinning and loss of the trilaminar appearance of the hyaline cartilage at the lateral femoral notch was shown in all subjects and was considered a normal finding. CONCLUSION: Fat-suppressed 3D SPGR imaging is more sensitive than standard MR imaging for the detection of abnormalities of the hyaline cartilage in the knee. Routine use of this technique may strengthen the role of MR imaging for noninvasive evaluation of internal derangements of the knee.

Adolescent↗