However, detection of uric acid crystals using aspiration may become difficult when synovial fluid is insufficient.

Joint aspiration is considered as the reference standard for the diagnosis of gout 4. However, some patients have asymptomatic hyperuricemia, which is not necessarily to develop into gout 3. Elevated level of uric acid in the serum correlates closely with gout. The diagnosis of gout is mainly based on clinical manifestations and laboratory tests. Chronic hyperuricemia predisposes to gouty arthritis 2. Gout is a crystalloid joint disease more common in adult males, with monosodium urate crystals deposited in joints and periarticular soft tissues 1. MLLSV derived from post-processing procedure of DECT is useful in discriminating gout patients from healthy people. When using the optimal cutoff of 1342В mg/cm 3, the sensitivity and specificity of MLLSV in identification of gout were 96.7% and 95% respectively. The area under ROC curve of MLLSV was 0.993 in identifying gout. MLLSV of gout patients was significantly higher than that of volunteers (1373.3вЂ‰В±вЂ‰23.0В mg/cm 3 vs. Receiver operating characteristic (ROC) curve was used to determine the performance. MLLSV obtained by this way was compared between gout patients and volunteers. Radiologists were asked to continuously increase the lower limit of display window of uric acid to decrease number of stained sites until the last stained site disappeared.

MLLSV was defined as the maximum lower limit of display window allowing only one stained site visible. 30 gout patients and 20 healthy volunteers were analyzed by using MLLSV. A new parameter derived from post-processing procedure, maximum lower limit with stain visible (MLLSV), was used by us to diagnose gout. ROI analysis is frequently used for obtaining acid content on rapid-kV-switching dual energy CT (DECT), providing inadequate accuracy.

Derived parameters flowjo 10