Objective To evaluate the association of exercise and knee-bending activities with magnetic resonance (MR)-based knee cartilage T2 relaxation times and morphologic abnormalities in asymptomatic subjects with and without osteoarthritis (OA) risk factors from the Osteoarthritis Initiative. Methods We studied 128 subjects with knee OA risk factors and 33 normal controls aged 45–55 years, with a body mass index of 18–27 kg/m2, and no knee pain. Subjects were categorized by exercise level, using the leisure activity component of the Physical Activity Scale for the Elderly, and by self-reported frequent knee-bending activities. Two radiologists graded the cartilage using the Whole Organ MR Imaging Score (WORMS) of right knee MR images. Cartilage was segmented and compartment specific T2 values were calculated. Statistical significance between the exercise groups and knee-bending groups was determined using multiple linear and logistic regression models. Results Among subjects with risk factors, light exercisers had lower T2 measurements than sedentary and moderate-strenuous exercisers (p=0.001); in women, moderate-strenuous exercise was associated with higher T2 values (p=0.001). Subjects without risk factors displayed no significant differences in T2 values by exercise. However, frequent knee-bending activities were associated with higher T2 values in both groups (p<0.02) and more severe cartilage lesions in the group with risk factors (p<0.001). Conclusions In subjects at risk for OA, light exercise was associated with low T2 measurements, whereas moderate-strenuous exercise in women was associated with high T2 values. Higher T2 values and WORMS grades were also found in frequent knee-benders and suggest greater cartilage degeneration in these individuals.

Objectives The aim of this work was to study anterior cruciate ligament (ACL) degeneration in relation to MRI-based morphological knee abnormalities and cartilage T2 relaxation times in subjects with symptomatic osteoarthritis. Methods Two radiologists screened the right knee MRI of 304 randomly selected participants in the Osteoarthritis Initiative cohort with symptomatic OA, for ACL abnormalities. Of the 52 knees with abnormalities, 28 had mucoid degeneration, 12 had partially torn ACLs, and 12 had completely torn ACLs. Fifty-three randomly selected subjects with normal ACLs served as controls. Morphological knee abnormalities were graded using the WORMS score. Cartilage was segmented and compartment-specific T2 values were calculated. Results Compared to normal ACL knees, those with ACL abnormalities had a greater prevalence of, and more severe, cartilage, meniscal, bone marrow, subchondral cyst, and medial collateral ligament lesions (all p<0.05). T2 measurements did not significantly differ by ACL status. Conclusions ACL abnormalities were associated with more severe degenerative changes, likely because of greater joint instability. T2 measurements may not be well suited to assess advanced cartilage degeneration.

No abstract

Objective To determine whether invasive lobular carcinoma (ILC) extent is more accurately depicted with preoperative MRI (pMRI) than conventional imaging (mammography and/or ultrasound). Methods After IRB approval, we retrospectively identified women with pMRIs (February 2005 to January 2014) to evaluate pure ILC excluding those with ipsilateral pMRI BI-RADS 4 or 5 findings or who had neoadjuvant chemotherapy. Agreement between imaging and pathology sizes was summarized using Bland-Altman plots, absolute and percent differences, and the intraclass correlation coefficient (ICC). Rates of underestimation and overestimation were evaluated and their associations with clinical features were explored. Results Among the 56 women included, pMRI demonstrated better agreement with pathology than conventional imaging by mean absolute difference (1.6 mm versus −7.8 mm, P &lt; 0.001), percent difference (10.3% versus −16.4%, P &lt; 0.001), and ICC (0.88 versus 0.61, P = 0.019). Conventional imaging more frequently underestimated ILC span than pMRI using a 5 mm difference threshold (24/56 (43%) versus 10/56 (18%), P &lt; 0.001), a 25% threshold (19/53 (36%) versus 10/53 (19%), P = 0.035), and T category change (17/56 (30%) versus 7/56 (13%), P = 0.006). Imaging–pathology size concordance was greater for MRI-described solitary masses than other lesion types for both MRI and conventional imaging (P &lt; 0.05). Variability of conventional imaging was lower for patients ≥ to the median age of 62 years than for patients younger than the median age (SD: 12 mm versus 22 mm, P = 0.012). Conclusion MRI depicts the size of pure ILC more accurately than conventional imaging and may have particular value for younger women.

Appendicitis is a common pathology most often caused by an appendicolith. Laparoscopic appendectomy has become the standard operative approach, but it has a higher risk of retained appendicoliths than open laparotomies. This report describes a case of a perihepatic abscess due to a retained appendicolith following laparoscopic intervention. The abscess was successfully drained and the appendicolith retrieved percutaneously under fluoroscopic guidance. A literature review and discussion about retained appendicoliths are provided as points for diagnostic consideration.