Schwannoma is a benign nerve sheath tumor composed of schwann cells. Most schwannoma arising in the middle ear are facial nerve schwannoma. In very rare occasions, schwannoma of the middle ear can arise from chorda tympani nerve. Hearing loss and tinnitus are the most common symptoms of patients with schwannoma of chorda tympani nerve and it can be treated by surgical excision. Recently, we treated a male patient with schwannoma of the chorda tympani nerve. This is the first case of schwannoma of the chorda tympani nerve reported in Korea. Herein, we present the case in detail with a review of the related literature.

Schwannoma is a benign nerve sheath tumor composed of schwann cells. Most schwannoma arising in the middle ear are facial nerve schwannoma. In very rare occasions, schwannoma of the middle ear can arise from chorda tympani nerve. Hearing loss and tinnitus are the most common symptoms of patients with schwannoma of chorda tympani nerve and it can be treated by surgical excision. Recently, we treated a male patient with schwannoma of the chorda tympani nerve. This is the first case of schwannoma of the chorda tympani nerve reported in Korea. Herein, we present the case in detail with a review of the related literature.
Chorda Tympani Nerve ; Ear, Middle ; Facial Nerve ; Hearing Loss ; Humans ; Korea ; Male ; Neurilemmoma ; Schwann Cells ; Tinnitus

The purpose of this study was to redesign a problem-based learning (PBL) curriculum and compare the differences between the previous and redesigned PBL based on the results of course satisfaction and student assessments. The PBL was redesigned using curriculum design guidelines (including revisions of curriculum objectives, learning components, learning environments, and assessment methods) that were developed based on previous studies and evaluation results. A comparative study was employed using course satisfaction surveys from the previous and redesigned curricula, and a total of 45 students participated. We also compared student assessment results from concept mapping, learning issue reports, modified essay questions, and reflection journals. We identified four key findings. First, we explored the possibility that the redesigned PBL could be implemented by student facilitators without professors as tutors. Second, the redesigned PBL fostered group dynamics that facilitated developing communication skills and collaborative learning through small-group discussions. Third, the new learning elements added in the redesigned PBL made a meaningful contribution to enhancing students’ clinical reasoning based on hypothetico-deductive reasoning. Fourth, concept maps in redesigned PBL contained more complex and various nodes and connections, and the levels of the nodes were more appropriate. The implications of this study can provide meaningful preliminary information for redesigning PBL curricula for medical students to develop their essential competencies through PBL.

Invasive fungal sinusitis is common in immunodeficiency patients and can spread into the orbit or intracranial cavity. The Onodi cell, which is one of the anatomical variations of the ethmoid sinus, refers to the space that has been pneumatized superolateral to the sphenoid sinus. We experienced a case of invasive fungal sinusitis that caused vision loss by invading the Onodi cells. Endoscopic sinus surgery and antifungal treatment successfully recovered the patient’s vision and we herein report on the case with a review of the literature.

Loeys-Dietz syndrome is a hereditary connective-tissue disorder first reported in 2005. It is caused by genetic defects in the transforming growth factor-beta (TGF-β) signaling pathway. TGF-β signaling plays an important role in connective-tissue development, differentiation, and homeostasis. Dysregulation of TGF-β signaling causes various defects in the skull, face, skeletal system, skin, and blood vessels. Symptoms of Loeys-Dietz syndrome include scoliosis, spider finger, joint laxity, club foot, hypertelorism, and cleft palate. In addition, aortic aneurysm, aortic dissection, bleeding tendency, delayed wound healing, allergic disease, and autoimmune disease have been reported. Here, we describe an 11-year-old male with type 1 diabetes mellitus who had frequent epistaxis and easy bruising from an early age, along with skin and joint hyperextension, atrophic scars, and long limbs. He was suspected of having a hereditary connective-tissue disorder and was diagnosed with Loeys-Dietz syndrome type 1 by next-generation sequencing. Similar to Marfan syndrome and Ehlers-Danlos syndrome, this disease has a high risk of aortic aneurysm and aortic dissection. In addition, because aortic dissection can occur at a young age, early diagnosis and periodic examination and treatment for cardiovascular diseases are necessary.

MicroRNAs (miRNAs) are known for their role in mRNA silencing via interference pathways. Repetitive elements (REs) share several characteristics with endogenous precursor miRNAs. In this study, 406 previously identified and 1,494 novel RE-derived miRNAs were sorted from the GENCODE v.19 database using the RepeatMasker program. They were divided into six major types, based on their genomic structure. More novel RE-derived miRNAs were confirmed than identified as RE-derived miRNAs. In conclusion, many miRNAs have not yet been identified, most of which are derived from REs.
Classification* ; Interspersed Repetitive Sequences ; MicroRNAs* ; RNA, Messenger

Ischiofemoral impingement (IFI) syndrome is an uncommon cause of gluteal and hip pain. We report on a case of a 20-year-old man who presented with chronic gluteal and hip pain with low back pain without a history of trauma or surgery. He was misdiagnosed with ankylosing spondylitis (AS) at another clinic. The patient was finally diagnosed with IFI syndrome according to pelvic magnetic resonance imaging findings at our hospital. After two weeks of medical and physical treatment, his pain showed gradual improvement. Because IFI syndrome is rarely reported in male patients, it might be misdiagnosed as AS. Therefore, IFI syndrome should be considered as a differential diagnosis of AS, particularly in young male patients with atypical pain characteristics.
Diagnosis, Differential* ; Hip ; Humans ; Low Back Pain ; Magnetic Resonance Imaging ; Male ; Spondylitis, Ankylosing* ; Young Adult

BACKGROUND AND OBJECTIVES: Cancer of the oral cavity is a disease of the head and neck that is difficult to treat. Periodic observation and biopsy are important for its early diagnosis once a premalignant lesion in the oral cavity is confirmed. The purpose of this study was to determine the importance of early excisional biopsy by investigating the histological features of oral leukoplakia and the rate of malignant change in the oral cavity.SUBJECTS AND METHOD: A total of 327 patients who underwent punch biopsy of oral cavity from January 2011 to December 2017 were reviewed retrospectively for the presence of initial gross lesions and for their biopsy results. The histological findings of 6 initial gross lesion groups were compared. Additional excisional biopsies were performed in the seven oral cavity subsites. RESULTS: There were 33 cases of oral leukoplakia. The punch biopsies of 3 of these cases (9.1%) showed malignancy. Additional excisional biopsies were performed in 6 cases, 4 of which were malignant (66.7%). Additional excisional biopsies of the tongue were performed in 14 cases (9.0%), 5 of which (35.7%) were malignant. The rate of atypia in leukoplakia (9.1%) was higher than in other atypia groups. Additional excisional biopsies were performed in 3 cases (100%) of atypia of leukoplakia, all of which were assessed to be malignant. CONCLUSION For tongue leukoplakia, performing an early excisional biopsy rather than an incisional biopsy is recommendable. Moreover, additional excisional biopsies are needed when the initial biopsy is suggestive of hyperkeratosis, parakeratosis, or atypia.

Objective: Recent studies have detailed the genomic landscape of endometrial cancer (EC); however, no study has focused on genetic alterations in advanced EC. We performed genomic profiling of patients with advanced EC using targeted next-generation sequencing (NGS). Methods: Archival tissue samples from 21 patients diagnosed with stage III and IV EC were obtained and subjected to NGS. Our data and the cancer genome atlas dataset were combined, and somatic mutation patterns were analyzed and compared according to the stage and histological type. Additionally, survival effects of specific mutated genes were analyzed. Results: Somatic mutation patterns of 38 genes were identified in 263 EC samples, and the most commonly mutated genes were PTEN and PIK3CA. PTEN was the most common in endometrioid histology, while PPP2R1A was the most commonly mutated gene in serous histology. The mutation rates of PPP2R1A and TP53 were significantly higher in advanced EC sample than in stage I samples (22.5% vs. 4.3% [p<0.001] and 8.4% vs. 1.4% [p=0.021], respectively). Survival analysis of the total population and endometrioid subgroup revealed that patients with PPP2R1A mutations had significantly shorter survival than did those without mutations (p=0.005 and p<0.001, respectively). Conclusion PPP2R1A mutations might have a role in dismal prognosis of advanced EC.

Background: Sarcopenia is commonly found in the elderly due to a decline in muscle mass.Many researchers have performed genome-wide association studies (GWAS) to find genetic risk factors of sarcopenia. Although many studies have discovered sarcopenia associated single nucleotide polymorphisms (SNPs), most of them are studies targeting Caucasians. The purpose of this study was to evaluate genetic correlation according to muscle mass in middle aged Koreans using data of the Korean Genome and Epidemiology Study (KOGES), a large population-based genomic cohort study. Methods: Baseline participants were 10,030 subjects aged 40 to 69 years who were from Ansan or Anseong in Gyeonggi-do, South Korea. Among them, 9,351 subjects with laboratory data available were included in this study. To identify sarcopenia associated variants, those in the top 30% and bottom 30% of muscle mass index (MMI) were compared. A total of 7,452 people with an MMI of 30-70% were excluded. A total of 1,004 people were also excluded due to missing data. Finally, 895 people were selected for this study. The Korea Biobank Array generated 500,568 SNPs for this dataset. Results: When subjects were divided into top 30% and bottom 30% of MMI, the top 30% had 169 men and 308 women and the bottom 30% had 220 men and 198 women. In men, age, body mass index (BMI), waist and hip were significantly (P < 0.005) different between top 30% and bottom 30% MMI groups. In women, age, BMI, waist, hip, and hypertension history were significantly different between the two MMI groups. There were 13 significant SNPs in men and 14 significant SNPs in women. Genes associated with variants in men based on the single-nucleotide polymorphism database (dbSNP) were LRP1B containing rs11679458 and RGS6 containing rs11848300. A gene associated with variants in women was Pi4K2A, which contained rs1189312 as a variant. In addition, rs11189312 was associated with expression quantitative trait loci (eQTL) of ZFYVE27 in skeletal muscles and other SNPs of ZFYVE27 (rs10882883, rs17108378, rs35077384) known to be associated with spastic paraplegia. The eQTL analysis revealed that rs11189312 was a variant associated with SNPs of ZFYVE27. Conclusions In the demographic study, significant results were found in BMI, waist, hip, history of hyperlipidemia, and sedentary life status in male group, and significant results were found in BMI, waist, hip, and hypertension history in female group. Variant rs11189312 was found to be a novel variant affecting ZFYVE27 expressed in skeletal muscles, suggesting that rs11189312 might be related to sarcopenia as a novel discovery of this study. Further study is needed to determine the association between sarcopenia and ZFYVE27 known to be associated with spastic paraplegia.