Incidence of contrast-induced nephropathy after a computed tomography scan

BACKGROUND AND AIMS

The term contrast-induced nephropathy is used to describe acute deterioration of renal function after the intravenous administration of iodinated contrast material. We aimed to estimate the incidence of contrast-induced nephropathy and to analyze the evolution of different biomarkers of renal function in patients who underwent computed tomography with intravenous contrast administration after premedication with oral hydration and N-acetylcysteine.

MATERIAL AND METHODS

This prospective observational study included 112 patients with chronic renal failure (glomerular filtration rate (GFR) 30ml-60ml/min/1.73m²) scheduled for computed tomography with intravenous iodinated contrast material. We recorded demographic variables, dose of contrast material, diabetes mellitus, hypertension, and serum hemoglobin. We measured serum creatinine and GFR after premedication and after the CT examination. We summarized variables as means, standard deviations, and percentages. We used the Wilcoxon and Mann-Whitney tests to compare pre- and post-CT values and Pearson's r to analyze correlations.

RESULTS

Incidence acute kidney injury: 0.9%; 95%CI: 0.36-1.4. Mean difference between pre- and post-CT creatinine: 0.04; 95%CI: 0.002-0.09, p<0.004. Mean difference between pre- and post-CT GFR: -3.06; 95%CI: -4.66 to -1.47), p<0.001.

CONCLUSIONS

The incidence of contrast-induced nephropathy in patients with chronic renal failure and GFR 30ml-60ml/min/1.73m² is low. The biomarkers of renal function analyzed improve in patients who receive premedication and the minimum dose of contrast material.

Development and Reliability of a Preliminary Foot Osteoarthritis Magnetic Resonance Imaging Score

OBJECTIVE

Foot osteoarthritis (OA) is very common but underinvestigated musculoskeletal condition and there is little consensus as to common magnetic resonance imaging (MRI) features. The aim of this study was to develop a preliminary foot OA MRI score (FOAMRIS) and evaluate its reliability.

METHODS

This preliminary semiquantitative score included the hindfoot, midfoot, and metatarsophalangeal joints. Joints were scored for joint space narrowing (JSN; 0-3), osteophytes (0-3), joint effusion/synovitis, and bone cysts (present/absent). Erosions and bone marrow lesions (BML) were scored (0-3) and BML were evaluated adjacent to entheses and at sub-tendon sites (present/absent). Additionally, tenosynovitis (0-3) and midfoot ligament pathology (present/absent) were scored. Reliability was evaluated in 15 people with foot pain and MRI-detected OA using 3.0T MRI multi-sequence protocols, and assessed using ICC as an overall score and per anatomical site.

RESULTS

Intrareader agreement (ICC) was generally good to excellent across the foot in joint features (JSN 0.90, osteophytes 0.90, effusion/synovitis 0.46, cysts 0.87), bone features (BML 0.83, erosion 0.66, BML entheses 0.66, BML sub-tendon 0.60) and soft tissue features (tenosynovitis 0.83, ligaments 0.77). Interreader agreement was lower for joint features (JSN 0.43, osteophytes 0.27, effusion/synovitis 0.02, cysts 0.48), bone features (BML 0.68, erosion 0.00, BML entheses 0.34, BML sub-tendon 0.13), and soft tissue features (tenosynovitis 0.35, ligaments 0.33).

CONCLUSION

This preliminary FOAMRIS demonstrated good intrareader reliability and fair interreader reliability when assessing the total feature scores. Further development is required in cohorts with a range of pathologies and to assess the psychometric measurement properties.

The usefulness of ultrasonography in the diagnosis of carpal tunnel syndrome

This study assessed the use of ultrasound in the diagnosis of carpal tunnel syndrome and to determine the best ultrasound criterion for diagnosis. Forty wrists of 27 patients with surgically proven moderate and severe carpal tunnel syndrome and 30 wrists of 15 controls were examined. Measurements of the cross-sectional area and the anteroposterior diameter of the median nerve at the inlet and outlet of the carpal tunnel were obtained. Patients also underwent electrophysiological evaluation. Median nerve ultrasonographic measurements were significantly higher in patients. The cross-sectional area of the median nerve at the tunnel inlet was found to be the most useful diagnostic criterion. The optimal cut-off value was 6.5 mm2 (sensitivity 89.5%, specificity 93%). Ultrasound parameters failed to correlate with the electrophysiological findings. The usefulness of ultrasonography in the diagnosis of carpal tunnel syndrome is discussed.

Ultrasonographic and magnetic resonance images of rotator cuff lesions compared with arthroscopy or open surgery findings

Our purpose was to compare the accuracy of ultrasonography (US) and magnetic resonance (MR) in the diagnosis of rotator cuff injuries (focusing on supraspinatus tears) using arthroscopy or open surgery findings. Using US and MR, we studied all painful shoulders seen during 1998 in our orthopaedic unit. Diagnosis was confirmed in 61 cases. The diagnosis of full thickness rotator cuff tear was highly specific on both imaging techniques (100% for US and 97.1% for MR) but was not as sensitive on US (57.7%) as on MR (80.8%). The diagnosis of partial tear was acceptably specific (67.9% for US and 75.5% for MR) but was not sensitive (overall, 12.5% for US vs 50% for MR). The specificity of a US diagnosis of a tear allows us to recommend surgery, thus making it a good imaging technique for the initial study of painful shoulders. The low sensitivity makes it necessary to undertake an additional MR study. If the MR also discovers no pathology, the sensitivity based on the US and MR images (92.7%) can be sufficient to avoid a false-negative diagnosis.