Purpose: Image registration is a fundamental task in various medical imaging studies and clinical image analyses, such as comparison of patient data with anatomical structures. In order to solve the problems of conventional image registration approaches, such as long computational time, recent deep-learning supervised and unsupervised methods have been extensively studied because of their excellent performance and fast computational time. In this study, we propose a deep-learningbased network for deformable medical image registration using unsupervised learning. Materials and Methods: In this paper, we solve the image-registration optimization problem by modelling a function using a convolutional neural network with polyphase decomposition to learn the spatial transformable parameters based on the input images and to generate the registration field. A spatial transformer is used to reconstruct the output warped image while imposing smoothness constraints on the registration field. With polyphase decomposition, our proposed method learns more features based on the input image pairs without the need for any ground-truth registration field. Results: Experimental results using 3D T1 brain MRI volume scans and compared with state-of-the-art image-registration methods demonstrated that our method provides better 3D-image registration. Conclusion Our proposed method uses less computational time in registering unseen pairs of input images during inference and can be applied for other unimodal image registration tasks, and the hyper-parameters can be adjusted for the specific task.

Generalized plane xanthoma is a group of plane xanthomas that appear as yellow to yellowish-brown flat patches or slightly-elevated plaques with a wide-spread distribution. This disease is not common and may occur in hyperlipidemic or nomolipidemic states. Generalized plane xanthoma with normolipidemia is often associated with multiple myeloma, other reticulo-endothelial malignancies and monoclonal gammopathy with unknown siginificance (MGUS). We report a case of generalized plane xanthoma associated with monoclonal gammopathy of unknown siginificance in a 40 year-old man.
Adult ; Humans ; Multiple Myeloma ; Paraproteinemias* ; Xanthomatosis*

Melanocytic nevus may be histologically associated with clefts or slits of nests, resembling lymphatic or vascular spaces. This unique histologic feature is known as an artifact of injection or tissue processing. The pseudovascular space may resemble the lymphatic invasion of malignant melanoma. Therefore it is important that dermatologists are aware of this histologic variant of melanoctic nevus in order to prevent misdiagnosis. We report three cases of melanocytic nevi with pseudovascular spaces in a 48-year-old, 43-year-old and 44-year-old women. Histologic examination of one case identified a compound melanocytic nevus and two cases identified intradermal nevi. Nevus cell nests were clustered in the dermis or dermoepidermal junction. Vessel-like spaces also were seen in the nevus cell nest. Immunohistochemically, the cells lining the pseudovascular space were positive for S-100 protein, and negative for factor VIII-related antigen and CD31 stain. We concluded that these spaces were lined by nevomelanocytes and were not truly vascular. We herein report on three melanocytic nevi with pseudovascular spaces.
Adult ; Artifacts ; Dermis ; Diagnostic Errors ; Female ; Humans ; Melanoma ; Middle Aged ; Nevus ; Nevus, Intradermal ; Nevus, Pigmented* ; S100 Proteins ; von Willebrand Factor

Chemotherapy-induced acral erythema (CIAE) is a toxic reaction to a number of different chemotherapeutic agents, and causes symmetrical, well-demarcated, painful erythema on the palms and soles which is self-limiting. CIAE with bullous reaction in relation to methotrexate has been reported, but it is more commonly associated with cytosine arabinoside. The differential diagnosis of this condition from more serious conditions such as graft-vs-host disease or toxic epidermal necrolysis is essential. In this paper, we report the case of a 65-year-old man who developed bullous acral erythema after the administration of high-dose methotrexate for the treatment of Non-Hodgkin's lymphoma.
Aged ; Cytarabine ; Diagnosis, Differential ; Erythema* ; Graft vs Host Disease ; Hand-Foot Syndrome ; Humans ; Lymphoma, Non-Hodgkin ; Methotrexate ; Stevens-Johnson Syndrome

Background: Osteoporosis is the most common metabolic bone disease and can cause fragility fractures. Despite this, screening utilization rates for osteoporosis remain low among populations at risk. Automated bone mineral density (BMD) estimation using computed tomography (CT) can help bridge this gap and serve as an alternative screening method to dual-energy X-ray absorptiometry (DXA). Methods: The feasibility of an opportunistic and population agnostic screening method for osteoporosis using abdominal CT scans without bone densitometry phantom-based calibration was investigated in this retrospective study. A total of 268 abdominal CT-DXA pairs and 99 abdominal CT studies without DXA scores were obtained from an oncology specialty clinic in the Republic of Korea. The center axial CT slices from the L1, L2, L3, and L4 lumbar vertebrae were annotated with the CT slice level and spine segmentation labels for each subject. Deep learning models were trained to localize the center axial slice from the CT scan of the torso, segment the vertebral bone, and estimate BMD for the top four lumbar vertebrae. Results: Automated vertebra-level DXA measurements showed a mean absolute error (MAE) of 0.079, Pearson’s r of 0.852 (P<0.001), and R2 of 0.714. Subject-level predictions on the held-out test set had a MAE of 0.066, Pearson’s r of 0.907 (P<0.001), and R2 of 0.781. Conclusion CT scans collected during routine examinations without bone densitometry calibration can be used to generate DXA BMD predictions.

Purpose: We present a dehazing algorithm using dark channel prior (DCP) and bright channel prior (BCP) to enhance the quality of retinal images obtained through conventional fundus photography. Methods: A retrospective analysis was conducted on retinal images from patients who visited Gangnam Sacred Heart Hospital between January 2000 and September 2022. These images were captured using a digital fundus camera (KOWA Nonmyd 8S Fundus Camera, KOWA Company, Nagoya, Japan) without pupil dilation. We used two mathematical algorithms: DCP only and DCP and BCP combined. The original, DCP-processed, and DCP & BCP-processed images were compared. Fisher's exact test was used to identify significant quality improvements. Results: The DCP and the newly proposed DCP plus BCP algorithm effectively eliminated haze and enhanced the contrast of cataract images. Notably, DCP demonstrated limited improvements in fundus photographs from patients with small pupils, whereas the proposed DCP plus BCP method effectively revealed previously obscured retinal details and vessels. However, these methods exhibited limited performance in severe cataracts compared to the clear images obtained after surgery. The quality enhancement with the proposed method was significant in photographs of patients with cataracts (p = 0.032) and small pupils (p < 0.01). Conclusions Our algorithm produced clearer images of blood vessels and optic disc structures, while significantly reducing artifacts in fundus images from patients with small pupils or cataracts. The proposed algorithm can provide visually enhanced images, potentially aiding physicians in the diagnosis of retinal diseases in patients with cataracts.

OBJECTIVE: To evaluate optimal management of an ovarian tumor in pregnancy METHODS: This study includes 89 cases of an ovarian tumor in pregnancy that required surgery at Catholic Medical Center, Kangnam St. Mary's hospital, Holy Family hospital of the Catholic University Medical College from January, 1990 to December, 2001. We collected 36 cases from 48 pregnant women who underwent emergency operation. And 53 cases were pregnant women who underwent elective operation. The student t-test and x2 test were used for statistical analysis. A P value of <0.05 was considered significant. RESULTS: The most common size of torsion of an ovarian tumor during pregnancy was 6-10 cm and the incidence was the most frequent during the first trimester of pregnancy. Pregnant women with torsion of an ovarian tumor who underwent emergency operation compared with those who underwent elective operation, the risk of preterm delivery were significant. But there were no fetal deaths reported, also there were no difference in the birth weight or the method of delivery. CONCLUSION: The torsion of an ovarian tumor dose not have a serious affect on the overall pregnancy. If the early diagnosis of the ovarian tumor is made and the malignancy is ruled out, it seems likely that the conservative care is better than the invasive method of operation during the second trimester of pregnancy just to prevent from preterm labor due to emergency operation of ovarian tumor.
Birth Weight ; Early Diagnosis ; Emergencies ; Female ; Fetal Death ; Humans ; Incidence ; Obstetric Labor, Premature ; Pregnancy Trimester, First ; Pregnancy Trimester, Second ; Pregnancy* ; Pregnant Women

Fibroma of tendon sheath presents as a small subcutaneous nodule that slowly increases in size, and it is most frequently found on the hands, with the thumb being the most common site of involvement. A 60-year-old woman presented with an asymptomatic, solitary, 1.5 x 2.0 cm-sized, firm, subcutaneous nodule on the left big toe. On magnetic resonance imaging view, the tumor was adherent to tendon sheath of the volar aspect of the left big toe. The skin biopsy specimen showed that the well-circumscribed tumor contained hypocellular, hyalinized, collagenous area and hypercellular densely-arranged collagen area with spindle-shaped fibroblasts and slit-like vascular channels. We herein report a rare case of fibroma of tendon sheath on the left big toe.
Biopsy ; Collagen ; Female ; Fibroblasts ; Fibroma* ; Hand ; Humans ; Hyalin ; Magnetic Resonance Imaging ; Middle Aged ; Skin ; Tendons* ; Thumb ; Toes*

Sweet's syndrome is a reactive process characterized by the abrupt onset of tender erythematous plaques and typical histological findings. Currently, the entity recognized as Sweet's syndrome ranges from classic Sweet's disease to a more aggressive neutrophilic process that may be associated with various diseases, malignancy and drug intakes. Also, extracutaneous manifestations of Sweet's syndrome have the potential to involve other organ systems. Pulmonary manifestation of Sweet's syndrome is rare and may be experienced as a cough, dyspnea, pleurisy or pulmonary infiltration upon chest X-ray. We, herein, report a 46-year-old woman with Sweet's syndrome who showed pulmonary infiltration and pleural effusion upon chest X-ray.
Cough ; Dyspnea ; Female ; Humans ; Middle Aged ; Neutrophils ; Pleural Effusion ; Pleurisy ; Sweet Syndrome* ; Thorax

Osteoma cutis is a rare disorder characterized by compact bone formation in the dermis or subcutaneous tissue. According to the absence or presence of previous cutaneous lesions, it is classified as primary and secondary forms. Miliary osteoma of the face is a form of primary osteoma cutis that generally occurs in middle-aged to older adult women. A 50-year-old woman presented with asymptomatic, multiple, 2~3 mm-diameter, skin-colored, firm papules on both cheeks for 5 years. The histopathologic specimen of the papule showed compact bone formation in the dermis. We herein report a rare case of military osteoma cutis on the face.
Adult ; Cheek ; Dermis ; Female ; Humans ; Middle Aged ; Military Personnel ; Osteogenesis ; Osteoma* ; Subcutaneous Tissue