Qmetrics Technologies

Rochester, NY, United States

Qmetrics Technologies

Rochester, NY, United States

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Gatti A.A.,McMaster University | Noseworthy M.D.,McMaster University | Stratford P.W.,McMaster University | Brenneman E.C.,McMaster University | And 4 more authors.
Journal of Biomechanics | Year: 2017

Purpose: To compare the acute effect of running and bicycling of an equivalent cumulative load on knee cartilage composition and morphometry in healthy young men. A secondary analysis investigated the relationship between activity history and the change in cartilage composition after activity. Methods: In fifteen men (25.8±4.2 years), the vertical ground reaction force was measured to determine the cumulative load exposure of a 15-min run. The vertical pedal reaction force was recorded during bicycling to define the bicycling duration of an equivalent cumulative load. On separate visits that were spaced on average 17 days apart, participants completed these running and bicycling bouts. Mean cartilage transverse relaxation times (T 2) were determined for cartilage on the tibia and weight-bearing femur before and after each exercise. T 2 was measured using a multi-echo spin-echo sequence and 3T MRI. Cartilage of the weight bearing femur and tibia was segmented using a highly-automated segmentation algorithm. Activity history was captured using the International Physical Activity Questionnaire. Results: The response of T 2 to bicycling and running was different (p=0.019; mean T 2: pre-running=34.27ms, pre-bicycling=32.93ms, post-running=31.82ms, post-bicycling=32.36ms). While bicycling produced no change (-1.7%, p=0.300), running shortened T 2 (-7.1%, p<0.001). Greater activity history predicted smaller changes in tibial, but not femoral, T 2. Conclusions: Changes in knee cartilage vary based on activity type, independent of total load exposure, in healthy young men. Smaller changes in T 2 were observed after bicycling relative to running. Activity history was inversely related to tibial T 2, suggesting cartilage conditioning. © 2017 Elsevier Ltd.


Hunter D.J.,University of Sydney | Altman R.D.,University of California at Los Angeles | Cicuttini F.,Monash University | Crema M.D.,Boston University | And 18 more authors.
Osteoarthritis and Cartilage | Year: 2015

Significant advances have occurred in our understanding of the pathogenesis of knee osteoarthritis (OA) and some recent trials have demonstrated the potential for modification of the disease course. The purpose of this expert opinion, consensus driven exercise is to provide detail on how one might use and apply knee imaging in knee OA trials. It includes information on acquisition methods/techniques (including guidance on positioning for radiography, sequence/protocol recommendations/hardware for magnetic resonance imaging (MRI)); commonly encountered problems (including positioning, hardware and coil failures, sequences artifacts); quality assurance (QA)/control procedures; measurement methods; measurement performance (reliability, responsiveness, validity); recommendations for trials; and research recommendations. © 2015 Osteoarthritis Research Society International. Published by Elsevier Ltd.


Simoni P.,Domanine du Sart Tilman | Jamali S.,Domanine du Sart Tilman | Albert A.,Domanine du Sart Tilman | Totterman S.,Qmetrics Technologies | And 5 more authors.
Skeletal Radiology | Year: 2013

Objective: To assess the intraobserver, interobserver, and test-retest reproducibility of minimum joint space width (mJSW) measurement of medial and lateral patellofemoral joints on standing skyline radiographs and to compare the mJSW of the patellofemoral joint to the mean cartilage thickness calculated by quantitative magnetic resonance imaging (qMRI). Materials and methods: A couple of standing skyline radiographs of the patellofemoral joints and MRI of 55 knees of 28 volunteers (18 females, ten males, mean age, 48.5 ± 16.2 years) were obtained on the same day. The mJSW of the patellofemoral joint was manually measured and Kellgren and Lawrence grade (KLG) was independently assessed by two observers. The mJSW was compared to the mean cartilage thickness of patellofemoral joint calculated by qMRI. Results: mJSW of the medial and lateral patellofemoral joint showed an excellent intraobserver agreement (interclass correlation (ICC) = 0.94 and 0.96), interobserver agreement (ICC = 0.90 and 0.95) and test-retest agreement (ICC = 0.92 and 0.96). The mJSW measured on radiographs was correlated to mean cartilage thickness calculated by qMRI (r = 0.71, p < 0.0001 for the medial PFJ and r = 0.81, p < 0.0001 for the lateral PFJ). However, there was a lack of concordance between radiographs and qMRI for extreme values of joint width and KLG. Radiographs yielded higher joint space measures than qMRI in knees with a normal joint space, while qMRI yielded higher joint space measures than radiographs in knees with joint space narrowing and higher KLG. Conclusions: Standing skyline radiographs are a reproducible tool for measuring the mJSW of the patellofemoral joint. The mJSW of the patellofemoral joint on radiographs are correlated with, but not concordant with, qMRI measurements. © 2013 ISS.


Shive M.S.,Piramal Healthcare Canada Ltd | Restrepo A.,Piramal Healthcare Canada Ltd | Totterman S.,Qmetrics Technologies | Tamez-Pena J.,Monterrey Institute of Technology | And 3 more authors.
Osteoarthritis and Cartilage | Year: 2014

Objective: Intra-lesional bony overgrowth (BO) identified during or following cartilage repair treatment is being frequently described through subjective reports focusing primarily on incidence. Our objective was to quantify the exact volume of intra-lesional BO at 12 months post-cartilage repair treatment, to determine if a correlation exists between the extent of BO and clinical outcomes, and to visualize and characterize the BO. Design: MRI scans were systematically obtained during a randomized clinical trial for cartilage repair (Stanish etal., 2013) that compared two microfracture-based treatments in 78 patients. Semi-automated morphological segmentation of pre-treatment, 1 and 12 months post-treatment scans utilizing a programmed anatomical atlas for all knee bone and cartilage structures permitted three-dimensional reconstruction, quantitative analysis, as well as qualitative characterization and artistic visualization ofBO. Results: Limited intra-lesional BO representing only 5.8±5.7% of the original debrided cartilage lesion volume was found in 78 patients with available MRIs at 12 months. The majority (80%) of patients had very little BO (<10%). Most occurrences of BO carried either spotty (56.4%) or planar (6.4%) morphological features, and the remaining balance (37.2%) was qualitatively unobservable by eye. Pre-existing BO recurred at 12 months in the same intra-lesional location in 36% of patients. No statistical correlations were found between BO and clinical outcomes. Conclusions: Intra-lesional BO following microfracture-based treatments may not be as severe as previously believed, its incidence is partly explained by pre-existing conditions, and no relationship to clinical outcomes exists at 12 months. Morphologically, observable BO was categorized as comprising either spotty or planar bone. © 2014 Osteoarthritis Research Society International.


Maly M.R.,McMaster University | Acker S.M.,University of Waterloo | Totterman S.,Qmetrics Technologies | Tamez-Pena J.,Monterrey Institute of Technology | And 4 more authors.
Journal of Biomechanics | Year: 2015

The objective was to determine the extent to which the external peak knee adduction moment (KAM) and cumulative knee adductor load explained variation in medial cartilage morphology of the tibia and femur in knee osteoarthritis (OA). Sixty-two adults with clinical knee OA participated (61.5±6.2 years). To determine KAM, inverse dynamics was applied to motion and force data of walking. Cumulative knee adductor load reflected KAM impulse and loading frequency. Loading frequency was captured from an accelerometer. Magnetic resonance imaging scans were acquired with a coronal fat-saturated sequence using a 1.0. T peripheral scanner. Scans were segmented for medial cartilage volume, surface area of the bone-cartilage interface, and thickness. Forward linear regressions assessed the relationship of loading variables with cartilage morphology unadjusted, then adjusted for covariates. In the medial tibia, age and peak KAM explained 20.5% of variance in mean cartilage thickness (p<0.001). Peak KAM alone explained 12.3% of the 5th percentile of medial tibial cartilage thickness (i.e., thinnest cartilage region) (p=0.003). In the medial femur, sex, BMI, age, and peak KAM explained 44% of variance in mean cartilage thickness, with peak KAM contributing 7.9% (p<0.001). 20.7% of variance in the 5th percentile of medial femoral cartilage thickness was explained by BMI and peak KAM (p=0.001). In these models, older age, female sex, greater BMI, and greater peak KAM related with thinner cartilage. Models of KAM impulse produced similar results. In knee OA, KAM peak and impulse, but not loading frequency, were associated with cartilage thickness of the medial tibia and femur. © 2015 Elsevier Ltd.


Maly M.R.,McMaster University | Acker S.M.,University of Waterloo | Totterman S.,Qmetrics Technologies | Tamez-Pena J.,Qmetrics Technologies | And 5 more authors.
Journal of Biomechanics | Year: 2015

The objective was to determine the extent to which the external peak knee adduction moment (KAM) and cumulative knee adductor load explained variation in medial cartilage morphology of the tibia and femur in knee osteoarthritis (OA). Sixty-two adults with clinical knee OA participated (61.5±6.2 years). To determine KAM, inverse dynamics was applied to motion and force data of walking. Cumulative knee adductor load reflected KAM impulse and loading frequency. Loading frequency was captured from an accelerometer. Magnetic resonance imaging scans were acquired with a coronal fat-saturated sequence using a 1.0. T peripheral scanner. Scans were segmented for medial cartilage volume, surface area of the bone-cartilage interface, and thickness. Forward linear regressions assessed the relationship of loading variables with cartilage morphology unadjusted, then adjusted for covariates. In the medial tibia, age and peak KAM explained 20.5% of variance in mean cartilage thickness (p<0.001). Peak KAM alone explained 12.3% of the 5th percentile of medial tibial cartilage thickness (i.e., thinnest cartilage region) (p=0.003). In the medial femur, sex, BMI, age, and peak KAM explained 44% of variance in mean cartilage thickness, with peak KAM contributing 7.9% (p<0.001). 20.7% of variance in the 5th percentile of medial femoral cartilage thickness was explained by BMI and peak KAM (p=0.001). In these models, older age, female sex, greater BMI, and greater peak KAM related with thinner cartilage. Models of KAM impulse produced similar results. In knee OA, KAM peak and impulse, but not loading frequency, were associated with cartilage thickness of the medial tibia and femur. © 2015 Elsevier Ltd.


Qi L.,Nanjing University | Wu S.Y.,Qmetrics Technologies | Meinel F.G.,Medical University of South Carolina | Zhou C.S.,Nanjing University | And 6 more authors.
Acta Radiologica | Year: 2016

Background: The smallest diagnostically appropriate amount of contrast medium should be used in coronary computed tomography angiography (CCTA). Purpose: To investigate the feasibility of prospectively ECG-triggered high-pitch CCTA using 30 mL of 270 mg I/mL contrast material, 80 kVp, and iterative reconstruction (IR). Material and Methods: Eighty-two consecutive patients underwent CCTA with a prospectively ECG-triggered highpitch protocol. Forty-three patients were examined at 100 kVp with filtered back projection after 60 mL of 370 mg I/mL contrast material was administered. Another 39 patients were examined at 80 kVp with IR after 30 mL of 270 mg I/mL contrast material was administered. Subjective and objective image quality was evaluated for each patient. Radiation doses were estimated and compared. Results: Mean attenuation, noise and signal-to-noise ratio in 80 kVp group were significantly lower than in 100 kVp group (all P<0.05), while there was no significant difference in contrast-to-noise ratio (CNR), although a trend towards a lower CNR in 80 kVp group was observed (P=0.099). The subjective image quality between the two groups was not significantly different (P=0.905). The effective dose and iodine load in 80 kVp group were reduced by 54% and 64%, respectively, when compared with 100 kVp group. Conclusion: Prospectively ECG-triggered high-pitch CCTA at 80 kVp with 30 mL of 270 mg I/mL contrast material and IR is feasible for patients with BMI less than 25 kg/m2 and reduces radiation dose and iodine load when compared with the standard CCTA protocol.


PubMed | Medical University of South Carolina, Nanjing University and Qmetrics Technologies
Type: Journal Article | Journal: Acta radiologica (Stockholm, Sweden : 1987) | Year: 2016

The smallest diagnostically appropriate amount of contrast medium should be used in coronary computed tomography angiography (CCTA).To investigate the feasibility of prospectively ECG-triggered high-pitch CCTA using 30mL of 270mg I/mL contrast material, 80kVp, and iterative reconstruction (IR).Eighty-two consecutive patients underwent CCTA with a prospectively ECG-triggered high-pitch protocol. Forty-three patients were examined at 100kVp with filtered back projection after 60mL of 370mg I/mL contrast material was administered. Another 39 patients were examined at 80kVp with IR after 30mL of 270mg I/mL contrast material was administered. Subjective and objective image quality was evaluated for each patient. Radiation doses were estimated and compared.Mean attenuation, noise and signal-to-noise ratio in 80kVp group were significantly lower than in 100kVp group (all P<0.05), while there was no significant difference in contrast-to-noise ratio (CNR), although a trend towards a lower CNR in 80kVp group was observed (P=0.099). The subjective image quality between the two groups was not significantly different (P=0.905). The effective dose and iodine load in 80kVp group were reduced by 54% and 64%, respectively, when compared with 100kVp group.Prospectively ECG-triggered high-pitch CCTA at 80kVp with 30mL of 270mg I/mL contrast material and IR is feasible for patients with BMI less than 25kg/m(2) and reduces radiation dose and iodine load when compared with the standard CCTA protocol.


Brisson N.M.,McMaster University | Stratford P.W.,McMaster University | Totterman S.,Qmetrics Technologies | Tamez-Pena J.G.,Qmetrics Technologies | And 4 more authors.
Journal of Applied Biomechanics | Year: 2015

Investigations of joint loading in knee osteoarthritis (OA) typically normalize the knee adduction moment to global measures of body size (eg, body mass, height) to allow comparison between individuals. However, such measurements may not reflect knee size. This study used a morphometric measurement of the cartilage surface area on the medial tibial plateau, which better represents medial knee size. This study aimed to determine whether normalizing the peak knee adduction moment and knee adduction moment impulse during gait to the medial tibial bone-cartilage interface could classify radiographic knee OA severity more accurately than traditional normalization techniques. Individuals with mild (N = 22) and severe (N = 17) radiographic knee OA participated. The medial tibial bone-cartilage interface was quantified from magnetic resonance imaging scans. Gait analysis was performed, and the peak knee adduction moment and knee adduction moment impulse were calculated in nonnormalized units and normalized to body mass, body weight × height, and the medial tibial bone-cartilage interface. Receiver operating characteristic curves compared the ability of each knee adduction moment normalization technique to classify participants according to radiographic disease severity. No normalization technique was superior at distinguishing between OA severities. Knee adduction moments normalized to medial knee size were not more sensitive to OA severity. © 2015 Human Kinetics, Inc.


Hunter D.J.,University of Sydney | Lohmander L.S.,Lund University | Lohmander L.S.,University of Southern Denmark | Makovey J.,University of Sydney | And 4 more authors.
Osteoarthritis and Cartilage | Year: 2014

Objective: Investigate the 5-year longitudinal changes in bone curvature after acute anterior cruciate ligament (ACL) injury, and identify predictors of such changes. Methods: In the KANON-trial (ISRCTN 84752559), 111/121 young active adults with an acute ACL tear to a previously un-injured knee had serial 1.5T MR images from baseline (within 5 weeks from injury) to 5 years after injury. Of these, 86 had ACL reconstruction (ACLR) performed early or delayed, 25 were treated with rehabilitation alone. Measures of articulating bone curvature were obtained from computer-assisted segmentation of MR images. Curvature (mm-1) was determined for femur, tibia, medial/lateral femur, trochlea, medial/lateral tibia. Age, sex, treatment, BMI, meniscal injury, osteochondral fracture on baseline MR images were tested for association. Results: Over 5 years, curvature decreased in each region (P<0.001) suggesting flattening of convex shapes and increased concavity of concave shapes. A higher BMI was associated with flattening of the femur (P=0.03), trochlea (P=0.007) and increasing concavity of the lateral tibia (LT) (P=0.011). ACLR, compared to rehabilitation alone, was associated with flatter curvature in the femur (P<0.001), medial femoral condyle (P=0.006) and trochlea (P=0.003). Any meniscal injury at baseline was associated with a more flattened curvature in the femur (P=0.038), trochlea (P=0.039), lateral femoral condyle (P=0.034) and increasing concavity of the LT (P=0.048). Conclusion: ACL injury is associated with significant changes in articulating bone curvature over a 5 year period. Higher BMI, baseline meniscal injury and undergoing ACL reconstruction (as distinct from undergoing rehabilitation alone) are all associated with flattening of the articulating bone. © 2014 Osteoarthritis Research Society International.

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