Acrylic Resins ; adverse effects ; Adult ; Breast Implantation ; adverse effects ; Female ; Humans ; Magnetic Resonance Imaging ; methods ; Middle Aged

BACKGROUNDThe imaging evaluation of pain in patients who have had a hip arthroplasty (HA) is challenging, and traditional imaging techniques, including magnetic resonance imaging (MRI) and computerized tomography (CT), are limited by metallic artifact. The purpose of the present study was to investigate the use of modified MRI techniques to visualize periprosthetic soft tissues and the bone-implant interface, and to evaluate the value of MRI for the assessment of patients with painful hip arthroplasty.

METHODSFifty-six painful hips in fifty-six patients following primary HA were assessed using optimized MRI, CT and standardized radiographs. The diagnosis of MRI was correlated with intraoperative findings as well as with microbiological and histological examinations (when available). The sensitivity and the specificity of MRI diagnosis were determined according to final diagnosis. The chi-square test was performed to detect a difference between MRI and final diagnosis.

RESULTSForty-eight patients have received revision surgery and final diagnosis were established. MRI was demonstrated high sensitivity and specificity in detecting aseptic loosening (93% and 95%), periprosthetic infection (94% and 97%), adverse local tissue reaction (100% and 100%) and periprosthetic fracture (100% and 100%). MRI was determined to be the most sensitive technique in detecting implant loosening for any reason, with a sensitivity of 93.8% for acetabular shell and 97.1% for femoral stem, compared to 81.3% and 80.0% on CT, 75.0% and 77.1% on radiographs.

CONCLUSIONSOptimized MRI was effective for the assessment of the periprosthetic soft tissues and bone. The use of modified magnetic resonance imaging parameters provided a useful adjunct to conventional examinations for the evaluation of patients with painful hip arthroplasty.

Arthroplasty, Replacement, Hip ; adverse effects ; Hip Prosthesis ; adverse effects ; Humans ; Magnetic Resonance Imaging ; methods ; Pain ; diagnosis ; etiology ; Prospective Studies

Humans ; Epidural Abscess/etiology* ; Acupuncture Therapy/adverse effects* ; Magnetic Resonance Imaging/adverse effects* ; Epidural Space ; Spinal Diseases

Metronidazole is a 5-nitroimidazole compound known as an antimicrobial agent widely used for the treatment of protozoal infection, anaerobic infection, Helicobacter pylori infection and hepatic encephalopathy. It may produce a number of neurologic side effects including peripheral neuropathy, seizure, encephalopathy, ataxic gait and dysarthritic speech. There have been ten or more reports of metronidazole-induced encephalopathy in the literatures including a few reports of brain imaging changes by magnetic resonance images (MRI). However, none of the case of metronidazole-induced encephalopathy in patients with hepatic encephalopathy has been reported yet. Recently, we experienced two cases of metronidazole-induced encephalopathy in patients with liver cirrhosis caused by chronic hepatitis B, which were diagnosed by brain MRI and MR spectroscopy. In this report, we present 2 cases of metronidazole-induced encephalopathy with MR imaging and MR spectroscopic changes including follow- up imaging performed after the discontinuation of the metronidazole with a review of the literatures.
Anti-Infective Agents/*adverse effects ; Brain Diseases/*chemically induced/diagnosis ; English Abstract ; Female ; Humans ; Magnetic Resonance Imaging ; Magnetic Resonance Spectroscopy ; Male ; Metronidazole/*adverse effects ; Middle Aged

A 77-year-old Chinese female patient presented with acute onset of left lower limb paraesthesia and weakness after she received an intramuscular injection for pain relief in the gluteal region. Magnetic resonance (MR) imaging of her lumbosacral spine and sacral plexus was performed. The MR imaging findings are reviewed and discussed.
Aged ; Female ; Humans ; Iatrogenic Disease ; Injections, Intramuscular ; adverse effects ; Magnetic Resonance Imaging ; Sciatic Neuropathy ; diagnosis ; etiology

Child ; Cold Temperature ; adverse effects ; Female ; Hand Injuries ; etiology ; Humans ; Magnetic Resonance Imaging ; Recurrence ; Syringomyelia ; complications

Cervical Vertebrae/diagnostic imaging* ; Humans ; Magnetic Resonance Imaging ; Nitrous Oxide/adverse effects* ; Spinal Cord Diseases/diagnostic imaging* ; Substance-Related Disorders

Adult ; Brain ; drug effects ; metabolism ; Female ; Hallucinogens ; adverse effects ; Humans ; Magnetic Resonance Imaging ; Motion Perception ; drug effects ; N-Methyl-3,4-methylenedioxyamphetamine ; adverse effects

OBJECTIVE: An ex vivo study found a copper-containing intrauterine device (IUD) to be safe for women undergoing an MRI examination at a 3.0-T field. No significant artifacts caused by the metallic implant were detected. However, there are still no in vivo data about these concerns. The aim of this study was to evaluate 3.0-T magnetic field interactions of copper-containing IUDs in vivo. MATERIALS AND METHODS: Magnetic field interactions and potential adverse events were evaluated in 33 women using a questionnaire-based telephone survey. Two experienced radiologists performed artifact evaluation on MR images of the pelvis. RESULTS: Eighteen patients were eligible for the survey. One patient reported a dislocation of the IUD after the MR examination. All other patients had no signs of field interactions. No IUD-related artifacts were found. CONCLUSION: MRI at 3.0-T is possible for women with copper-containing IUDs. However, consulting a gynecologist to check the correct position of the IUD and exclude complications after an MR examination is highly recommended. High-quality clinical imaging of the female pelvis can be performed without a loss in image quality.
Adult ; Artifacts ; *Copper ; Female ; Hot Temperature ; Humans ; *Intrauterine Devices, Copper/adverse effects ; Magnetic Fields ; Magnetic Resonance Imaging/adverse effects/*methods ; Middle Aged ; Pelvis

The present study investigated the effects of prenatal exposure to the magnetic resonance imaging (MRI) magnetic fields on the synaptic ultrastructure of hippocampal formation of rats at different postnatal development stages. Pregnant rats with gestation of 12-18 days were exposed to the magnetic fields used for MRI clinical applications. When the offspring were 1, 2, or 5-month-old, the synaptic morphologic parameters were measured in female offspring. In the 2-month-old MRI group, the curvature of synaptic interface, the length of active zone and the surface density per unit volume (S(v)) of active zone in the dentate gyrus (DG) decreased significantly, and the width of synaptic cleft increased in the CA1 area. In the 5-month-old MRI group, the width of synaptic cleft increased, the thickness of postsynaptic density and the curvature of synaptic interface decreased significantly in the CA1 region, and the width of synaptic cleft increased in the DG. No significant change was observed in the 1-month-old group. These results suggest that prenatal exposure to the medical magnetic fields causes synaptic ultrastructural changes. The relationship of these changes with behavioral impairments was discussed.
Animals ; Female ; Hippocampus ; pathology ; Magnetic Resonance Imaging ; adverse effects ; Pregnancy ; Prenatal Exposure Delayed Effects ; Rats ; Rats, Sprague-Dawley ; Synapses ; pathology