Gouty arthritis is an arthritis associated with hyperuricemia and is characterized by the deposition of urate crystals. Urate crystals form within the joints, leading to joint inflammation and pain.
Ultrasound imaging features have important clinical applications in the diagnosis and evaluation of gouty arthritis, and this article introduces the application of ultrasound in the diagnosis and treatment of gout in detail.
Diagnosis of gout
Diagnosis
The dual-track sign, tophi, and aggregates are specific ultrasound manifestations for the diagnosis of gouty arthritis, and the dual-track sign has been included in the gout classification criteria jointly published by EULAR and ACR in 2015 as characteristic changes of ultrasound.
Intra-articular "aggregates"
Hyperechoic foci that are heterogeneous independent of location (may be located within joints or tendons) remain hyperreflective even when gain is minimized or the angle of the sound wave changes, sometimes with posterior acoustic shadows.
Arrows show aggregates in the Achilles tendon (t is the Achilles tendon)
Dual-track sign
Urate crystals are deposited on the surface of the cartilage, parallel to the hyperechoic cortex beneath the cartilage, thus forming a "bi-track sign".
chalkstone
Musculoskeletal ultrasonography can visually reflect changes in gout crystals: increased crystals indicate that the dose or type of drug is not appropriate, and the drug needs to be adjusted or increased; Decreased crystallization suggests that treatment is effective and can be maintained.
Gout disease assessment
Bone erosion
The bony cortex is discontinuous in two vertical planes within or outside the articular cavity. The edges of the bone erosion are often irregular, the base is not clear, and the bone surface is often insect-eaten on ultrasound.
In addition, ultrasound microblood flow and energy Doppler can observe the blood supply to the early synovium, which can more accurately assess the disease and guide medication.
Abundant blood flow signals can be seen on the synovium of hyperplasia of the first metatarsophalangeal joint of the right foot
(Acute gout attack)
Joint effusion
Joint effusions are defined as compressible, displaceable anechoic areas that do not show Doppler flow signals internally.
First metatarsophalangeal joint effusion and synovial hyperplasia in the left foot
Complications
complication
Gout kidneys
In more than 90% of patients with recurrent gout attacks, histological findings of gout kidney are seen. Intramedullary echogenicity is enhanced, and hyperechoic is present. There is no significant change in kidney size and cortical thickness, and renal atrophy and cortical thinning may occur as the disease progresses. Histologically, needle-like crystalline urate is deposited in the renal medulla, and chronic interstitial nephritis with granulomas can be seen around it.
↑ When kidney damage is caused, the ultrasonography department detects a strong echo mass in the renal vertebrae.
Ultrasound can be involved in the whole process of gout disease, observe the occurrence and development of gout, and effectively and dynamically observe the changes and outcomes of joint lesions in the middle and late stages, which is of great value for the evaluation of treatment efficacy and prognosis, and can guide clinical practice and avoid bone and joint destruction caused by repeated attacks.