Journal of the Korean Society of Radiology最新文献

The accessory tendon of the extensor hallucis longus is a common type of extensor hallucis longus variation. This is a case of a 38-year-old female patient who initially considered conservative treatment for a suspected partial rupture, but finally underwent surgery after being diagnosed with a complete rupture of the main tendon and accessory tendon medial to the main tendon on MRI scan.

Primary malignant melanoma in breast parenchyma (PMB) is an extremely rare disease, and the most common presentation is a palpable breast lump. To the best of our knowledge, a case of PMB presenting as a breast abscess has not been reported in English literatures. We present a case of PMB that manifested as a recurrent breast abscess in a 71-year-old woman. On MRI, an enhancing solid mass with a cystic or necrotic portion was revealed with some high signal intensities on precontrast-enhanced T1-weighted images and a dark rim on T2-weighed images. The MRI features played a pivotal role in identifying the underlying malignant condition and making an accurate diagnosis of this rare case of PMB with unusual clinical presentation.

Common femoral artery pseudoaneurysm is a potentially serious complication of peripheral angiography. There have been few prior reports of simultaneous pseudoaneurysm in both common femoral arteries after percutaneous access. Here we report the case of a 58-year-old male patient who presented with phlegmon or abscess a few days after bilateral femoral access, after which newly developed bilateral femoral pseudoaneurysm with wide neck was observed on CT angiography 2 months after infection treatment. Because the patient refused surgery for pseudoaneurysm, a stent-graft was inserted in the left side, and percutaneous thrombin injection under US guidance with balloon occlusion was performed for the right side. Most pseudoaneurysms occur immediately after the causative procedure. However, there have been some cases in which pseudoaneurysms may occur several weeks or months later; it is therefore necessary to check the risk factors and to carefully observe the hemostasis site.

Purpose: This study aimed to evaluate the US features of the parathyroid glands (PTGs) using surgical specimens of normal PTGs obtained during thyroid surgery.

Materials and methods: This study included 34 normal PTGs from 17 consecutive patients who underwent thyroid surgery between December 2020 and March 2021. All normal PTGs were histologically confirmed by intraoperative frozen-section biopsy for autotransplantation. Surgically resected parathyroid specimens were scanned in sterile normal saline using high-resolution US prior to autotransplantation. The US features of echogenicity (hyperechogenicity or hypoechogenicity), echotexture (homogeneous or heterogeneous), size, and shape (ovoid or round) were retrospectively evaluated. The echogenicity of the three PTGs was compared with that of the thyroid parenchyma of the resected thyroid specimens in two patients.

Results: All PTGs showed hyperechogenicity similar to that of gauze soaked in normal saline. Homogeneous hyperechogenicity was observed in 32/34 (94.1%) patients, and the echogenicity of the three PTGs was hyperechoic compared with that of the thyroid parenchyma. The long diameter of the PTGs ranged from 5.1 mm to 9.8 mm (mean, 7.1 mm) and the shape of the PTGs was ovoid in 33/34 (97.1%) patients.

Conclusion: The echogenicity of normal PTG specimens was consistently hyperechoic, and the small ovoid homogeneously hyperechoic structure was a characteristic US feature of the PTGs.

Purpose: To investigate the MRI markers for the prediction of amyloid β (Aβ)-positivity in mild cognitive impairment (MCI) and Alzheimer's disease (AD), and to evaluate the differences in MRI markers between Aβ-positive (Aβ [+]) and -negative groups using the machine learning (ML) method.

Materials and methods: This study included 139 patients with MCI and AD who underwent amyloid PET-CT and brain MRI. Patients were divided into Aβ (+) (n = 84) and Aβ-negative (n = 55) groups. Visual analysis was performed with the Fazekas scale of white matter hyperintensity (WMH) and cerebral microbleeds (CMB) scores. The WMH volume and regional brain volume were quantitatively measured. The multivariable logistic regression and ML using support vector machine, and logistic regression were used to identify the best MRI predictors of Aβ-positivity.

Results: The Fazekas scale of WMH (p = 0.02) and CMB scores (p = 0.04) were higher in Aβ (+). The volumes of hippocampus, entorhinal cortex, and precuneus were smaller in Aβ (+) (p < 0.05). The third ventricle volume was larger in Aβ (+) (p = 0.002). The logistic regression of ML showed a good accuracy (81.1%) with mini-mental state examination (MMSE) and regional brain volumes.

Conclusion: The application of ML using the MMSE, third ventricle, and hippocampal volume is helpful in predicting Aβ-positivity with a good accuracy.

An umbilical venous catheter (UVC) is commonly placed for central venous access in preterm or critically ill full-term neonates to provide total parenteral nutrition (TPN) and medication. However, UVCs can result in complications, including infection, portal vein thrombosis, and hepatic tissue injury. The inadvertent administration of hypertonic fluid through a malpositioned UVC can also cause hepatic parenchymal damage with mass-like fluid collection that simulates a tumorous condition during imaging. Ultrasonography and radiographic examinations play an essential role in detecting UVC-related complications. This pictorial essay aims to present the imaging findings of UVC-related hepatic complications in neonates.

Gerstmann-Sträussler-Scheinker (GSS) disease is a rare hereditary prion disease which is clinically characterized by a progressive cerebellar ataxia followed by cognitive impairment. We report a rare case of GSS disease in a 39-year-old male patient who complained of a progressive gait disturbance followed by dysarthria with cognitive impairment, after five months from the onset of initial symptom. His brain MRI scan revealed multifocal symmetric diffusion restricted lesions with T2/FLAIR hyperintensities in bilateral cerebral cortices, basal ganglia, and thalami. His family members also manifested similar symptoms in their 40-50s, suggesting the possibility of a genetic disease. Finally, he was genetically diagnosed with GSS disease by real-time quaking-induced conversion and prion protein (PRNP) gene sequencing test.

Perianal fistula is a common inflammatory condition in the general population and affects the area around the anal canal. Although most cases are benign, they cause serious morbidity and require surgical treatment due to a high risk of recurrence. MR imaging is a gold standard technique for the evaluation of perianal fistulas and provides accurate information on the anatomy of the anal canal, its relationship to the anal sphincter complex, accurate identification of secondary tracts or abscesses, and reporting associated complications. MR imaging can help monitor treatment effects and determine treatment methods. Crohn's disease-related fistulas often require medical rather than surgical treatment. The radiologist is required to know the anatomy and MR imaging findings of the perianal fistula to present an accurate diagnosis to the clinician.

Immunoglobulin G4 (IgG4)-related disease is a rare systemic fibroinflammatory condition characterized by organomegaly or tumefactive lesions associated with lymphoplasmacytic infiltration rich in IgG4 plasma cells. We report a case of IgG4-related disease involving the subcutaneous layer of the left upper arm in a 48-year-old female presenting with an unusual soft tissue mass. US and MRI showed an irregular infiltrative soft tissue mass, indicating possible malignancy or inflammation. We discuss the diagnostic criteria, histopathologic features, radiological features, and treatment of IgG4-related disease.