Chest CT Imaging Features of the Pulmonary Sequelae in Four Patients with COVID-19

With the ongoing coronavirus disease 2019 (COVID-19) pandemic, there is an increasing interest in the sequelae and care in recovered patients. Although the long-term sequelae of COVID-19 are still unknown, recently published reports suggest that some of the patients have persistent symptoms and show radiologic abnormalities after discharge. Herein, we present cases of four patients with previous COVID-19 infection manifesting pulmonary sequelae, including pulmonary fibrosis or organizing pneumonia pattern with persistent dyspnea after recovery.

Persistent Trigeminal Artery Variant Terminating in the Ipsilateral Superior Cerebellar Artery

Persistent trigeminal artery (PTA) represent an unusual remnant of the fetal carotid-basilar anastomosis. Persistent trigeminal artery variant (PTAV) is a rare anastomosis between the internal carotid artery and cerebellar artery, without an interposing basilar artery segment. We report the case of 49-year-old female with an incidentally discovered, rare variation of PTA that directly terminated in the ipsilateral superior cerebellar artery. The variation was observed on CT angiography, digital subtraction angiography, and MR angiography. Additionally, we reviewed the embryogenesis of PTA and PTAV and discussed the clinical implications of this variation.

Anomalous Origins of the Bilateral Vertebral Arteries Arising from the Aortic Arch:A Case Report

Various anomalous origins of the vertebral arteries (VAs) have been reported. However, anomalous origins of the bilateral VAs arising directly from the aortic arch are extremely rare. We encountered a 60-year-old male who developed sudden-onset right hemiparesis with an incidentally discovered rare origins of the bilateral VAs from aortic arch. CT angiography demonstrated the right VA originating from the aortic arch distal to the left subclavian artery and left VA originating from the aortic arch between the left common carotid artery and the left subclavian artery. The possible embryological mechanism of this variant was also reviewed. If the VA can not be found in the usual position during the procedure, a rare variant of the VA with anomalous origin should be considered. Understanding these variations is important to avoid unexpected events during endovascular procedures or surgery.

Anomalous Origins of the Bilateral Vertebral Arteries Arising from the Aortic Arch:A Case Report

Various anomalous origins of the vertebral arteries (VAs) have been reported. However, anomalous origins of the bilateral VAs arising directly from the aortic arch are extremely rare. We encountered a 60-year-old male who developed sudden-onset right hemiparesis with an incidentally discovered rare origins of the bilateral VAs from aortic arch. CT angiography demonstrated the right VA originating from the aortic arch distal to the left subclavian artery and left VA originating from the aortic arch between the left common carotid artery and the left subclavian artery. The possible embryological mechanism of this variant was also reviewed. If the VA can not be found in the usual position during the procedure, a rare variant of the VA with anomalous origin should be considered. Understanding these variations is important to avoid unexpected events during endovascular procedures or surgery.

Periprosthetic Fractures following Total Knee Arthroplasty

Recently, as the elderly population increases, the incidence of total knee arthroplasty has increased, with a concomitant increase in the frequency of periprosthetic fractures. To determine the treatment plan for fractures, the treatment method should be determined by the patient's age, osteoporosis, fixation status of the implant, and type of fracture. In recent years, operative treatment with reduction and stable fixation, rather than non-operative treatment, was used to promote early joint movement and gait. On the other hand, it is necessary to select an appropriate operative method to reduce complications of surgery, such as nonunion and infection, and expect a good prognosis. In this review, periprosthetic fractures were divided into femur, tibia, and patella fractures, and their causes, risk factors, classification, and treatment are discussed.

Computed Tomography Image Analysis of the Fusion Site of Subtalar Arthrodesis for Traumatic Arthritis after a Displaced Intraarticular Calcaneal Fracture

PURPOSE: The study examined the fusion site and characteristics of the subtalar arthrodesis after intraarticular calcaneal fractures using computed tomography. MATERIALS AND METHODS: The clinical results and computed tomographic analysis of the fusion site were reviewed in 18 patients who were followed-up for a minimum of six months after undergoing subtalar arthrodesis due to traumatic arthritis caused by an intra-articular calcaneal fracture from December 2012 to April 2017. RESULTS: An evaluation of clinical results after subtalar arthrodesis revealed statistically significant improvements. In all cases, arthritis was found in the injured articular surface, which was displaced superolaterally from the initial primary fracture line of the calcaneus. Six months after arthrodesis, the subtalar fusion rate was 80.0% (16/20). Of these, 14 cases had a cannulated screw inserted in the uninjured site that is medial to the primary fracture line. Joint fusion was observed on the uninjured articular surface in 17 cases (85.0%). CONCLUSION: Joint fusion was initially achieved at the uninjured posterior facet after subtalar arthrodesis due to traumatic arthritis caused by a displaced intra-articular calcaneal fracture. This suggests that meticulous surgical techniques and cannulated screw positioning at the uninjured site will promote joint fusion.

Duodenal Niemann-Pick C1-like 1 expression was negatively correlated with liver X receptor expression in nonalcoholic fatty liver disease

BACKGROUND/AIMS@#Intestinal cholesterol absorption includes intestinal Niemann-Pick C1-like 1 (NPC1L1) and is an important target pathway in nonalcoholic fatty liver disease (NAFLD). We investigated the expression of NPC1L1 and its correlation with liver X receptor (LXR) expression in peripheral mononuclear (PMN) cells in patients with NAFLD.@*METHODS@#We evaluated intestinal expression of NPC1L1 in 25 NAFLD patients and 28 healthy controls. We calculated the mRNA expression levels of LXR and farnesoid X receptor (FXR), which are master players of cholesterol metabolism in PMN cells. The protein expression of ABCA1, ABCG5/8, NPC1L1, SREBP, LXR, FXR, and CD36 was measured on tissue samples from the duodenum and ileum.@*RESULTS@#The expression of LXR (p = 0.01) and FXR (p = 0.03) in PMN cells was increased in the NAFLD group compared to the control group. Duodenal NPC1L1 decreased in the NAFLD group compared to the healthy controls (3.38 ± 1.4 vs. 2.42 ± 1.2, p = 0.05). NPC1L1 expression in the duodenum was negatively correlated with LXR expression in PMN cells. Expression of LXR and FXR in the ileum was also negatively correlated with the expression of LXR in PMN cells.@*CONCLUSIONS@#Duodenal NPC1L1 expression was decreased in NAFLD and was negatively correlated with LXR expression in PMN cells.

High-Altitude Cerebral Edema Evaluated with MRI: A Case Report

High-altitude cerebral edema (HACE) is a rare life-threatening condition observed in individuals who climb high altitudes. This report describes the case of a 38-year-old man who recently climbed a 5000-m-high mountain, showing the following radiologic findings at 3 different anatomical locations: 1) increased T2 signal intensity (SI) without restricted diffusion, with full recovery in the posterior limb of the left internal capsule; 2) increased T2 SI with restricted diffusion, with full recovery in the splenium of the corpus callosum; and 3) increased T2 SI with restricted diffusion and microbleeds, resulting in bilateral encephalomalacia in the globus pallidus. Herein, we report the concurrent typical and atypical radiologic findings of this rare condition caused by vasogenic and cytotoxic edema.

Pigmented Villonodular Synovitis of the Ankle and Subtalar Joint Treated by Surgical Excision and Ligament Reconstructions: A Case Report / 대한족부족관절학회지

Diffuse pigmented villonodular synovitis (PVNS) involving ankle joint needs complete mass excision and total synovectomy to reduce recurrence rate, while surrounding ligaments can be easily damaged. So the concurrent ligament reconstruction should be considered for post-excisional instability in subtalar joint as well as lateral ankle joint. We describe our experience in the management of a diffuse type PVNS, invades lateral talocrural joint extended to subtalar joint and introduce a new technique of all-in-one reconstruction for anterior talofibular,calcaneofibular and cervical ligament. Our new reconstruction technique applying modified Chrisman and Snook technique is useful in stabilization for deficiencies of the ligament complexafter PVNS excisionat lateral ankle and subtalar joint.

Is Total Knee Arthroplasty a Viable Treatment Option in Octogenarians with Advanced Osteoarthritis?

PURPOSE: This study directly compared clinical assessment scores and short-term systemic complications after total knee arthroplasty (TKA) between a group of patients aged 80 or older (141 patients) and another group of patients aged between 65 and 70 years (616 patients) with advanced osteoarthritis. MATERIALS AND METHODS: We retrospectively investigated 757 osteoarthritic patients who underwent primary TKA from January 2007 to January 2011 with a follow-up of 1 year. The surgery was performed using an extramedullary alignment guide instrument without invasion of the intramedullary canal to decrease embolic load and blood loss. RESULTS: At 1 year after surgery, the mean Knee Society knee score was improved in both groups (from 63.6 to 83.2 in octogenarians and from 68.3 to 89.0 in the younger group) and the level of satisfaction was excellent in both groups (8 in octogenarians and 8.3 in the younger group), even though there was no notable change in function score in the octogenarians (from 61.0 to 61.9 in the octogenarians and from 62.3 to 73.6 in the younger group). The total incidence of systemic complications (3.4% vs. 1.2%, p=0.400) and surgical complications (2.1% vs. 0.5%, p=0.229) showed no significant difference between groups. CONCLUSIONS: TKA yielded favorable clinical outcomes with a comparatively low postoperative complication rate in octogenarians despite the negligible functional improvement.

Osteonecrosis of Femoral Head Treated with Extracorporeal Shock Wave Therapy: Analysis of Short-term Clinical Outcomes of Treatment with Radiologic Staging / 대한고관절학회지

PURPOSE: To evaluate clinical results of extracorporeal shock wave therapy (ESWT) with radiographic staging on patients with avascular necrosis of femoral head (AVNFH). MATERIALS AND METHODS: We evaluated 24 patients diagnosed with AVNFH (32 hip joints) who were treated with ESWT from 1993 to 2012. Average follow-up period was 27 months, and the average age of patients was 47.8 years. The Association Research Circulation Osseous (ARCO) system was used to grade radiographic stage prior to treatment. For this study patients were divided into two groups based on their ARCO stage, group 1 (ARCO stages I and II) and group 2 (ARCO stage III). Comparative analyses were done between the two groups using the visual analogue scale (VAS) score and the Harris hip score (HHS) at pre-treatment and 3, 6, 12, and 24 months after treatment. Failure was defined when radiographic stage progressed or arthroplasty surgery was needed due to clinical exacerbation. RESULTS: Both groups showed clinical improvements with VAS scoring at final follow-up (group 1: median 7 to 1.5, P<0.001; group 2: mean 7 to 4, P=0.056). Using HHS, group 1 showed a significant improvement (from 65.5 to 95 [P<0.001]), while no significance was observed for group 2 (P=0.280). At final follow-up, 3 hips from group 1 and one hip from group 2 showed radiographic improvement; however, two patients underwent total hip arthroplasty due to persistent pain and dysfunction. CONCLUSION: ESWT can be considered as an interventional option before surgical treatment in patients with not only early stage AVNFH but also with mid stage.

Bioequivalence of Two Erlotinib Formulations in Healthy Volunteers

BACKGROUND: Erlotinib is a tyrosine kinase inhibitor prescribed for the treatment of non-small cell lung cancer and pancreatic cancer. The aim of this study was to compare the safety and pharmacokinetics (PK) of a generic (test) formulation of erlotinib with those of a reference formulation in healthy volunteers. METHODS: A randomized, open-label, single-dose two-treatment, two-period, two-sequence, crossover study was conducted in Clinical Trials Center, Chungnam National University Hospital with 40 healthy men. Subjects orally received either one 150 mg tablet of the test or the corresponding dose of the reference, and crossover phases were separated by 14-day washout. Plasma samples were collected up to 72 hr post-dose. Plasma erlotinib concentrations were determined by liquid chromatography-tandem mass spectrometry. PK parameters were calculated by non-compartmental analysis. The safety was monitored throughout the study. RESULTS: A total of 21 cases of adverse events were reported. They are mild and relieved without an intervention. There was no serious adverse event. Median times to peak concentration of two formulations were 3.0. Means [SD] for peak concentration (Cmax) and area under the plasma concentration-time curve (AUC) of the test were 1,298 [346] microg/L and 25,318 [7,668] hrxmicrog/L. Those of the reference were 1,193 [378] microg/L and 24,853 [8,419] hrxmicrog/L. Geometric mean ratios (90% confidence intervals) for the test to the reference were 1.10 (1.02-1.18) for Cmax and 1.02 (0.97-1.09) for AUC. CONCLUSION: Two formulations were safe and well-tolerated. PK findings suggest that the test formulation is equivalent to the reference in terms of pharmacokinetics.

Detection of Hepatic Lesion: Comparison of Free-Breathing and Respiratory-Triggered Diffusion-Weighted MR imaging on 1.5-T MR system

PURPOSE: To compare free-breathing and respiratory-triggered diffusion-weighted imaging on 1.5-T MR system in the detection of hepatic lesions. MATERIALS AND METHODS: This single-institution study was approved by our institutional review board. Forty-seven patients (mean 57.9 year; M:F = 25:22) underwent hepatic MR imaging on 1.5-T MR system using both free-breathing and respiratory-triggered diffusion-weighted imaging (DWI) at a single examination. Two radiologists retrospectively reviewed respiratory-triggered and free-breathing sets (B50, B400, B800 diffusion weighted images and ADC map) in random order with a time interval of 2 weeks. Liver SNR and lesion-to-liver CNR of DWI were calculated measuring ROI. RESULTS: Total of 62 lesions (53 benign, 9 malignant) that included 32 cysts, 13 hemangiomas, 7 hepatocellular carcinomas (HCCs), 5 eosinophilic infiltration, 2 metastases, 1 eosinophilic abscess, focal nodular hyperplasia, and pseudolipoma of Glisson's capsule were reviewed by two reviewers. Though not reaching statistical significance, the overall lesion sensitivities were increased in respiratory-triggered DWI [reviewer1: reviewer2, 47/62(75.81%):45/62(72.58%)] than free-breathing DWI [44/62(70.97%):41/62(66.13%)]. Especially for smaller than 1 cm hepatic lesions, sensitivity of respiratory-triggered DWI [24/30(80%):21/30(70%)] was superior to free-breathing DWI [17/30(56.7%):15/30(50%)]. The diagnostic accuracy measuring the area under the ROC curve (Az value) of free-breathing and respiratory-triggered DWI was not statistically different. Liver SNR and lesion-to-liver CNR of respiratorytriggered DWI (87.6+/-41.4, 41.2+/-62.5) were higher than free-breathing DWI (38.8+/-13.6, 24.8+/-36.8) (p value <0.001, respectively). CONCLUSION: Respiratory-triggered diffusion-weighted MR imaging seemed to be better than free-breathing diffusion-weighted MR imaging on 1.5-T MR system for the detection of smaller than 1 cm lesions by providing high SNR and CNR.

Detection of Hepatic Lesion: Comparison of Free-Breathing and Respiratory-Triggered Diffusion-Weighted MR imaging on 1.5-T MR system

PURPOSE: To compare free-breathing and respiratory-triggered diffusion-weighted imaging on 1.5-T MR system in the detection of hepatic lesions. MATERIALS AND METHODS: This single-institution study was approved by our institutional review board. Forty-seven patients (mean 57.9 year; M:F = 25:22) underwent hepatic MR imaging on 1.5-T MR system using both free-breathing and respiratory-triggered diffusion-weighted imaging (DWI) at a single examination. Two radiologists retrospectively reviewed respiratory-triggered and free-breathing sets (B50, B400, B800 diffusion weighted images and ADC map) in random order with a time interval of 2 weeks. Liver SNR and lesion-to-liver CNR of DWI were calculated measuring ROI. RESULTS: Total of 62 lesions (53 benign, 9 malignant) that included 32 cysts, 13 hemangiomas, 7 hepatocellular carcinomas (HCCs), 5 eosinophilic infiltration, 2 metastases, 1 eosinophilic abscess, focal nodular hyperplasia, and pseudolipoma of Glisson's capsule were reviewed by two reviewers. Though not reaching statistical significance, the overall lesion sensitivities were increased in respiratory-triggered DWI [reviewer1: reviewer2, 47/62(75.81%):45/62(72.58%)] than free-breathing DWI [44/62(70.97%):41/62(66.13%)]. Especially for smaller than 1 cm hepatic lesions, sensitivity of respiratory-triggered DWI [24/30(80%):21/30(70%)] was superior to free-breathing DWI [17/30(56.7%):15/30(50%)]. The diagnostic accuracy measuring the area under the ROC curve (Az value) of free-breathing and respiratory-triggered DWI was not statistically different. Liver SNR and lesion-to-liver CNR of respiratorytriggered DWI (87.6+/-41.4, 41.2+/-62.5) were higher than free-breathing DWI (38.8+/-13.6, 24.8+/-36.8) (p value <0.001, respectively). CONCLUSION: Respiratory-triggered diffusion-weighted MR imaging seemed to be better than free-breathing diffusion-weighted MR imaging on 1.5-T MR system for the detection of smaller than 1 cm lesions by providing high SNR and CNR.

Various Sonographic Findings of Kuttner Tumors of the Bilateral Submandibular Gland and Right Parotid Gland

Chronic sclerosing sialadenitis or a Kuttner tumor is a benign inflammatory condition characterized by firm swelling of the salivary gland. This disease may clinically mimic Sjogren's syndrome or a salivary gland origin neoplasm. Various sonographic findings in patients with a Kuttner tumor were described in previous studies. Here, we describe a rare case of a 60-year-old man presenting with a non-tender right-sided parotid mass and swelling of both submandibular glands. A pathologic examination of the lesions in the right parotid gland and both submandibular glands indicated the presence of Kuttner tumors of various sonographic appearances.

Ultrasound Findings of Lymphoid Hyperplasia of the Appendix in Children: Differentiation from Acute Appendicitis

PURPOSE: To evaluate the ultrasound (US) findings that can help differentiate lymphoid hyperplasia in the appendix from acute appendicitis. MATERIALS AND METHODS: A total of 1230 patients (below 20 years old) suspected of having appendicitis received an appendectomy between November, 1999, and March, 2008, with US findings in 27 patients with pathologically proven lymphoid hyperplasia of the appendix. Of 167 patients that received an appendectomy from January, 2007, to December, 2007, 52 patients with acute appendicitis were retrospectively reviewed as a control group. Retrospective review of US images was performed by two radiologists who were blinded to the pathologic results. The review was based on 12 ultrasonographic criteria derived from reports on the diagnostic findings of the appendicitis. RESULTS: Compared with acute appendicitis, lymphoid hyperplasia in appendix had a smaller diameter (7.14+/-1.22 mm vs 9.37+/-1.80 mm, p < 0.001) and less wall thickening (1.38+/-0.36 mm vs 1.74 +/- 0.56 mm, p =0.001). Periappendicular inflammation (p < 0.001), intraluminal air (p = 0.006), round shape in transverse scan (p = 0.002), increased blood flow on color Doppler US (p = 0.03) were also different. CONCLUSIONS: US is a useful modality to differentiate lymphoid hyperplasia in the appendix from acute appendicitis.

A Case of Empyema Caused by Streptococcus Constellatus / 결핵및호흡기질환

Streptococcus constellatus (S. constellatus) is a commensal microorganism belonging to the "Streptococcus milleri" group, but may cause infections in different locations in immunocompromised patients. The infection of S. constellatus has high mortality and morbidity due to its tendency to cause abscesses in infected patients, which require immediate surgical drainage for effective treatment. We report on a 72-year-old woman with end stage renal disease, who suffered from dyspnea and general weakness that had developed over 7 days. Chest CT showed loculated pleural effusion. S. constellatus was cultured from exudative pleural effusions and confirmed by an analysis of 16S rRNA sequence. The patient was treated with drainage of pleural effusion and piperacillin/tazobactam for 5 weeks.

Isolation and Culture of Adult Neural Stem Cells from Guinea Pig Tympanic Membrane / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Tympanic membrane perforation is an important clinical problem found in various populations of the world. In large number of cases, acute traumatic perforations heal spontaneously, and in the healing process, stem cells appear to play an important role. However, no studies have been reported regarding somatic stem cells in the tympanic membrane. Herein, we tried to show that guinea pig's tympanic membrane contains cells that display the characteristic features of stem cells. MATERIALS AND METHOD: The tympanic membrane was obtained from the guinea pig. The cells were cultured in a medium with epidermal growth factor (EGF) and fibroblast growth factor (FGF). Proliferating cells were checked with stem cell markers, bromodeoxyuridine (BrdU) and nestin. Differentiated cells from stem cells are checked with betaIII tubulin and S-100. RESULTS: We observed that some of the cultured cells from the tympanic membrane were stained with both stem cell markers, BrdU and nestin. And we observed that these cells differentiated into neuron and gilal cells, which expressed betaIII tubulin and S-100, respectively. CONCLUSION: These results suggest that the tympanic membrane of guinea pigs may have neural stem cells. Further study is needed for finding the origin of stem cells.

Perineural Cyst in Upper Lumbar Spine: A Case Report / 대한척추외과학회지

Spinal perineural cyst rarely appears in the upper lumbar spinal region as compared it occurrence at other spinal region. These cysts seldom cause radiating pain and neurologic symptoms because the majority of these cysts involve the sacral portion of the spine. Spinal perineural cyst can be recognized incidentally on magnetic resonance imaging while differentiating other diseases that cause back pain. The differential diagnosis of symptoms is needed to rule out whether or not the intraspinal cystic mass is the actual cause of radiculopathy. We report here on a case of perineural cyst at a left neural foramen of L2-3 and the patient displayed neurologic manifestations. The patient had progressively aggravated low back pain and sciatica of two years duration. MRI well demonstrated neural compression of the left 2nd lumbar neural root. Relief of symptoms were achieved by performing posterior decompression (hemilaminectomy, fascectomy & decompression of the ligamentum flavum), excision of the cyst and posterolateral fusion of L2-3.

Primary Mucinous Adenocarcinoma of a Seminal Vesicle Cyst Associated with Ectopic Ureter and Ipsilateral Renal Agenesis: a Case Report

Primary adenocarcinoma of the seminal vesicles is a rare neoplasm. Congenital seminal vesicle cysts are commonly associated with unilateral renal agenesis or dysgenesis. To the best of our knowledge, mucinous adenocarcinoma of the seminal vesicle cyst that's associated with an ectopic ureter opening into the seminal vesicle and ipsilateral renal agenesis has not been described in the radiological literature. We report here on the radiological findings of a primary adenocarcinoma of a seminal vesicle cyst in this condition.