ABSTRACT
Objective To discuss the MRI findings of common complications following hip arthroplasty and their association with operative and pathological findings to improve the early diagnosis and etiological differential diagnosis for common complications following hip arthroplasty. Methods Forty-six patients with hip arthroplasty complication were included in this study. We observed prosthesis location, signal changes between prosthesis and bone, and periprosthesis signal changes, signal changes of articular capsule, adjacent soft tissue and bone on MR images. Diagnostic value of MRI in detecting hip arthroplasty complication was evaluated with operative and pathological findings as reference standard. Results Complications following hip arthroplasty included aseptic loosening (n=26), osteolysis (n=12), infection (n=12), heterotopic ossification (n=4), pseudoneoplasm (n=4) and periarthroplasty fracture (n=1). The MRI finding suggestive of aseptic loosening in 24 cases was a smooth intermediate signal intensity layer along the interface. Osteolysis is seen as soft tissue signal intensity material replacing normal high signal intensity fatty marrow in 12 cases. Bone marrow edema, bone destruction, fluid collection, estracapsular collections, periprosthetic muscle edema, and sinus were predictors of infection. On MRI, mature heterotopic ossification had the appearance of cancellous bone in 5 cases. Pseudoneoplasm represents fluid signal intensity with intermediate signal intensity pseudocapsule in 5 cases. Periprosthetic fracture included hypointesense fracture lines, periosteal reaction, and periprosthetic muscle edema in one patient. Conclusion MRI is useful in detecting osseous and soft-tissue abnormalities in patients with hip implants.
ABSTRACT
<p><b>BACKGROUND</b>The 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.</p><p><b>METHODS</b>Fifty-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.</p><p><b>RESULTS</b>Forty-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.</p><p><b>CONCLUSIONS</b>Optimized 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.</p>
Subject(s)
Humans , Arthroplasty, Replacement, Hip , Hip Prosthesis , Magnetic Resonance Imaging , Methods , Pain , Diagnosis , Prospective StudiesABSTRACT
Tubulointerstitial fibrosis (TIF) is a common pathological feature of end-stage kidney disease. Previous studies showed that upregulation of TGFbeta1 notably contributed to the chronic renal injury and irbesartan halted the development of TIF in rats with 5/6 renal mass reduction. This study was to investigate the effects of irbesartan on chronic TIF and the mechanism involved TGFbeta1 in the rodent model of chronic renal failure involving 5/6 nephrectomy. The results showed that irbesartan significantly attenuated the rise in blood pressure and tubulointerstitial injury observed in this model. Masson staining of the renal tissue revealed that there appeared severe renal tubule atrophy and fibrosis in operation group, but the lesion was attenuated mostly in irbesartan-treated group. Immunohistochemistry showed that irbesartan treatment apparently decreased the protein expression of TGFbeta1 which was up-regulated in operation groups. Western blot showed that irbesartan treatment down-regulated the expression of TGFbeta1, phosphorylated smad2 (p-smad2), AT1R and phosphorylated p38 (p-p38) MAPK, but significantly up-regulated the protein expression of smad6 as compared with operation group. These findings suggest that irbesartan attenuates hypertension and reduces the development of TIF in rats with 5/6 renal mass reduction via changes in the expression of these proteins at least including smad6, TGF-beta1, p-smad2, AT1 and p-p38 MAPK.
ABSTRACT
We analyzed parasitic diseases diagnosed by tissue biopsy specimens at KyungHee Medical Center (KMC) from 1984 to 2005. The total number of parasite infection cases was 150 (0.07%) out of the total 211,859 biopsy specimens submitted for histopathological examinations. They consisted of 62 cysticercosis, 23 sparganosis, 16 paragonimiasis, 15 amebiasis, 11 anisakiasis, 11 clonorchiasis, 3 ascariasis, 2 scabies, 2 enterobiasis, 2 trichuriasis, 1 leishmaniasis, 1 taeniasis, and 1 thelaziasis. Out of 62 cysticercosis cases, 55 were detected in subcutaneous tissues or the central nerve system. Eighteen out of 23 sparganosis cases were involved in muscular and subcutaneous tissues. In most anisakiasis cases, the involved organ was the stomach. The lung and the pleura were the most common site of paragonimiasis. The incidence of parasitic diseases during the first 5 years (1984-1988) was the highest of all observed periods. After 1989, similar incidences were shown throughout the period. Whereas cysticercosis was diagnosed in 34 cases during 1984-1988, no case has been diagnosed since 2000. In the case of sparganosis, the chronological incidence was almost uniform throughout the period 1984-2005. Paragonimiasis showed a similar tendency to cysticercosis. In gender and age distribution of parasitic diseases, men showed higher incidence rates than females, and the age groups of the 40s or older indicated higher infection frequencies than other age groups. Therefore, these results are a significant report to appear the tendency of human parasitic disease diagnosed by tissue biopsy in association with parasitosis at KMC in Seoul.