Background: Cerebral cavernous malformations (CCM) present with varied symptoms and are diagnosed only on MRI, which shows characteristic appearances. Genetic factors play a role, with familial cases following an autosomal dominant inheritance pattern. Case: This is the clinical case of a 48-year-old woman with a history of long-standing arterial hypertension. She was admitted to the Stroke Department with headache, nausea, vomiting, right-sided sensory disturbance, and dysarthria. Based on the clinical presentation and MRI, multiple supra- and infratentorial and intraxial lesions with heterogeneous components were identified, exhibiting hypointense rings on T1- and T2-weighted sequences and a “blooming” effect on T2*/GRE sequences, characteristic of cerebral cavernomas, displaying a “popcorn” appearance. Conclusion In CCM, management requires a multidisciplinary approach, with surgical resection the gold standard for symptomatic cases. Accurate determination of familial or sporadic origin is crucial for tailored treatment.

Background: Choriocarcinomas after full-term pregnancies are a rare entity. Case presentation: A 34-year-old woman was admitted to the hospital with a seizure in a comatose state. A computed tomography scan revealed an intracerebral haemorrhage in the right parietal region. A chest CT scan showed a single metastatic lesion in the right upper lung field. The patient delivered a viable infant at 39 weeks of gestation, 4 months before the hospitalisation. Her pregnancy course was uncomplicated. Despite receiving intensive treatment, the patient died 1 day later. Choriocarcinoma was diagnosed at the autopsy. Conclusion Metastatic choriocarcinoma should always be in the differential diagnosis for women of childbearing age presenting with unexplained stroke-like symptoms.

Background: Primary central nervous system lymphoma (PCNSL) is a rare form of extranodal non-Hodgkin lymphoma that is confined to the brain, spinal cord, leptomeninges, or eyes. Case: Our patient was a 52-year-old immunocompetent male who presented with progressive ataxia, dizziness, weakness and pain in both legs, imbalance, nausea, bladder/bowel retention and fever for over 18 months. After repetitive brain and spinal MRI, he was diagnosed with encephalomeningomyelitis and received four courses of steroid therapy, but his clinical symptoms continued to worsen. He was unable to undergo brain tissue analysis due to his persistent fever. We present a case of PCNSL based on the history, clinical presentation, repeated brain imaging, cerebrospinal fluid analysis, and clinical treatment. Conclusion Early diagnosis through accurate interpretation of imaging and timely management is crucial for improved outcomes in PCNSL.

Background: Although the prevalence of complete edentulism has decreased over the past decade, there are significant regional differences. For example, among adults aged 15 and older in the United States, the prevalence of complete edentulism is 4.9%, while in China, approximately one in four elderly individuals is completely edentulous. The primary treatment for this condition is complete dentures. Over the past ten years, the use of digital technology for fabricating complete dentures has increased substantially, prompting comparative studies between conventionally fabricated and digitally fabricated complete dentures. Aim: To compare the initial fit of complete maxillary dentures fabricated using digital and conventional methods, and to evaluate the dimensional changes after one month of denture use. Materials and Methods: This study was conducted based on the decision No. 24-25/05-02 of the Research Ethics Committee of the Mongolian National University of Medical Sciences. The study was carried out at the School of Dentistry, specifically in the Department of Prosthodontics and the Digital Technology Laboratory. A total of 30 complete dentures-15 fabricated digitally and 15 fabricated using conventional methods-were made for 15 patients with complete edentulism. Each denture was used for a period of one month, after which denture retention was re-evaluated using a force gauge (AMF500). Statistical analysis was performed using SPSS version 26.0, and differences were considered significant at p<0.05. Result: To compare the differences between digital and conventional methods at baseline, the Wilcoxon Signed-Rank Test was performed. The results showed a statistically significant difference (Z=-2.045, p=0.041, p<0.05). At the one-month follow-up, the Friedman test revealed a significant difference among the four groups (χ²(3)=11.40, p=0.01). Pairwise comparisons using the Wilcoxon Signed-Rank Test indicated that retention of conventional complete dentures at one month was significantly different (Z=-2.803, p=0.005), and retention of CAD/CAM-fabricated complete dentures at one month was also significantly different (Z=-2.497, p=0.013). However, comparison of baseline and one-month retention between CAD/CAM and conventional dentures showed no statistically significant difference (p=0.059). Conclusion At baseline, retention of conventional complete dentures was statistically higher compared to CAD/CAM-fabricated dentures. At the one-month follow-up, retention improved for both conventional and digital dentures.

Background: In the field of oral and maxillofacial prosthetics, implant-supported or tooth-supported prostheses have been proven to be an effective treatment option for patients with partial edentulism. However, complete dentures remain the sole treatment option for fully edentulous patients. Over the past decade, the use of CAD/CAM technology for fabricating complete dentures has increased substantially, leading to a growing number of studies comparing conventional complete dentures with those produced using CAD/CAM. In our country, however, there is a scarcity of research comparing the retention of maxillary complete dentures fabricated by conventional and CAD/CAM methods. Aim: To compare the retention of maxillary complete dentures fabricated by CAD/CAM and conventional methods. Materials and Methods: This study was conducted using a clinical trial design. The research was carried out at the Department of Prosthodontics, School of Dentistry, Mongolian National University of Medical Sciences (MNUMS), utilizing the Digital Technology Laboratory. The retention of 15 maxillary complete dentures fabricated by CAD/CAM and conventional methods was measured using a force gauge (AMF500). Statistical analysis was performed using SPSS version 26.0, and differences were considered statistically significant at p<0.05. Result: The mean retention of maxillary complete dentures fabricated by the conventional method (8.85±9.10N) was higher than that of dentures fabricated by the CAD/CAM method (4.95±2.57N). To assess the difference between the two fabrication methods, the Wilcoxon Signed Ranks Test was performed. The results showed Z=-2.045, p=0.041 (p<0.05), indicating that the retention of conventional dentures was statistically significantly higher than that of CAD/CAM dentures. Conclusion The retention of maxillary complete dentures fabricated by the conventional method was statistically significantly higher than that of dentures fabricated by the CAD/CAM method.

Background: One of the primary morphological changes in complete edentulism is the resorption of the alveolar bone. Following tooth extraction, the dominance of bone resorption processes leads to a reduction in both the height and width of the alveolar ridge. This process is most intensive during the first year of edentulism. The mandible resorbs faster than the maxilla. In recent years, panoramic radiography has been widely used to assess alveolar bone resorption, particularly by using the mental foramen (foramen mentale) as a stable anatomical landmark to reduce measurement errors and enhance assessment accuracy. Aim: To study the correlation between mandibular alveolar ridge resorption and its contributing factors in completely edentulous patients. Materials and Methods: The study was conducted at the Mongolian National University of Medical Sciences (MNUMS), focusing on the Central Hospital of Oral and Maxillofacial Dentistry. A total of 50 patients were enrolled. Data collection included an 11 questionnaire and panoramic radiographs. Quantitative values of mandibular alveolar resorption were measured from the radiographs, and statistical analysis was performed using SPSS 26. Results: The mean age of participants was 68.2±9.2 years, with 32% being male (n=16) and 68% female (n=34). Mandibular alveolar ridge resorption was 34.6±14.4 in males and 50.4±11.6 in females, showing a statistically significant difference between genders (p < 0.001). However, no statistically significant correlation was found between alveolar ridge resorption and the duration of edentulism in either gender (p=0.288). Similarly, there was no significant correlation between resorption and the duration of denture wear (p=0.133) or the number of prosthetic treatments received (p=0.213). Conclusion Mandibular alveolar bone resorption is more pronounced in females. However, the duration of edentulism, the duration of denture wear, and the frequency of prosthetic treatments do not appear to significantly influence the extent of alveolar ridge resorption.

Background: Senear-Usher Syndrome, also known as pemphigus erythematosus, is a rare autoimmune blistering skin disease characterized by overlapping clinical, histopathological, and immunological features of both lupus erythematosus and pemphigus foliaceus. Case Presentation: We report the case of a 46-year-old male diagnosed with Senear-Usher Syndrome, who presented to the outpatient clinic of the National Dermatology Center of Mongolia and received inpatient treatment. Diagnosis: The patient exhibited diffuse, thick, pale gray scales and yellowish crusts on the scalp. Multiple brown hyperpigmented macules of various shapes and sizes, vivid erythema, and a few erosions were observed on the nose, cheeks, trunk, and upper and lower extremities. A few pea-sized vesicles containing clear fluid were scattered on the back. Nikolsky's sign was weakly positive, and Besnier-Meshchersky's sign was positive. Histopathology: Histopathological analysis of skin biopsies revealed hyperkeratosis, parakeratosis, and acanthosis in the epidermis. Subcorneal cleft formation with neutrophils within the cleft was noted, along with perivascular infiltration of neutrophils and lymphohistiocytes in the superficial dermis. Treatment: The patient received treatment with hydroxychloroquine, systemic and topical corticosteroids, and symptomatic therapy. Outcome: Following treatment, the patient's general condition improved significantly. The erosions re-epithelialized, and the vesicles resolved, leaving behind brown hyperpigmented macules. The patient is currently under regular follow-up by a dermatologist and a family physician. Conclusion Senear-Usher Syndrome is a rare disease with a high potential for misdiagnosis. Therefore, an accurate diagnosis relies on a comprehensive evaluation of clinical features, histopathological examination, and direct and indirect immunofluorescence studies.

Background: Cutaneous squamous cell carcinoma (cSCC) accounts for approximately 20% of all malignant skin tumors and is the second most common skin cancer worldwide. Although the prognosis is generally favorable when diagnosed at an early stage, large tumors with invasion into surrounding tissues and metastasis to regional lymph nodes tend to exhibit more aggressive behavior. In particular, reconstruction of large tissue defects following wide excision of skin tumors remains a significant clinical challenge. Case presentation: We present a rare case of cSCC in a 69-year-old male patient, located on the left hip. The lesion measured 13x9 cm, with well-demarcated borders from the surrounding normal skin, prominently elevated above the skin surface, and characterized by a bluish-brown color. The central superior portion of the lesion was depressed and ulcerated with infiltrative features. Histopathological examination confirmed a well-differentiated, keratinizing invasive cutaneous squamous cell carcinoma. Computed tomography revealed a soft tissue density mass at the skin surface of the left lower abdomen, along with enlargement of the left inguinal lymph nodes. Treatment: The patient underwent wide local excision of the tumor along with regional lymph node dissection (lymphadenectomy). The resulting large tissue defect was reconstructed using an anterolateral thigh (ALT) free flap. During surgery, indocyanine green (ICG) angiography was performed to assess flap perfusion, and handheld Doppler was used to evaluate vascular flow. Results: The postoperative course was uneventful. The flap survived successfully with adequate perfusion. Histopathological examination confirmed negative surgical margins, and no metastasis was identified in the lymph nodes. The patient remains in stable condition without any complaints or symptoms and is under regular follow-up by an oncologist. Conclusion This case demonstrates that combining wide excision with free flap reconstruction is an effective approach for managing large cSCC. In addition, the use of indocyanine green (ICG) angiography for intraoperative assessment of vascular perfusion enhances flap viability and contributes to improved surgical outcomes.

Abstract Epilepsy, a neurological disorder characterized by recurrent seizures, affects millions of people worldwide. Significant advancements in both diagnostic and therapeutic approaches have greatly improved outcomes, particularly for individuals with drug-resistant epilepsy. Modern neurostimulation techniques such as Responsive Neurostimulation (RNS), Deep Brain Stimulation (DBS), and Vagus Nerve Stimulation (VNS) have demonstrated effectiveness in reducing seizure frequency in these patients. Additionally, emerging technologies like gene therapy and optogenetics are being explored to better understand the underlying mechanisms of epilepsy and hold promise as future treatment modalities.Traditional imaging techniques often fail to detect subtle epileptogenic zones. However, the introduction of ultra high-field 7T MRI scanners represents a major breakthrough. These advanced scanners use eight transmitters to generate higher-resolution images, reducing signal dropout and enabling the identification of previously undetected lesions. In one study involving 31 patients, 58% had their treatment plans modified based on 7T MRI findings, highlighting its potential to inform surgical decision-making. In terms of pharmacological treatment, newer medications such as sultiame, cannabidiol (CBD), and non-pharmacological approaches like the ketogenic diet have emerged as additional therapeutic options for drug-resistant epilepsy. These developments contribute to more effective, personalized management strategies for epilepsy. In summary, the landscape of epilepsy diagnosis and treatment is rapidly evolving. Innovations in imaging and therapeutic interventions are offering new hope for patients with drug-resistant epilepsy. Ongoing research and clinical trials remain essential to further refine these approaches and improve patient outcomes.

Background: The COVID-19 pandemic has profoundly impacted mental health, particularly exacerbating conditions such as depression, anxiety, insomnia, post-traumatic stress disorder (PTSD), and emotional disorders among hospitalized patients. This study examined the prevalence of COVID-19-related mental health issues and risk factors in hospitalized patients affiliated with MNUMS, compared to a control group. Aim: To assess the prevalence of mental health disorders such as depression, anxiety, insomnia, and post-traumatic stress disorder (PTSD), and to identify their associated risk factors. Materials and Methods: The study was conducted at hospitals under MNUMS, including the Mongolian-Japanese Hospital, Central Hospital, and the National Center for Maternal and Child Health. A total of 552 participants (399 case group, 153 control group) who were hospitalized were included. Depression (PHQ-9≥10), anxiety (GAD-7≥10), insomnia (ISI≥15), and PTSD (PCL-5≥33) were assessed using standardized scales. Analysis was performed using chi-square tests and binary logistic regression (crude odds ratio [cOR]/adjusted odds ratio [aOR], 95% confidence interval [CI]), adjusted for group, age, and sex. Results: In the case group, depression (23.1% vs. 13.7%, p=0.015, cOR=1.884 [1.124-3.156]), anxiety (16.8% vs. 11.1%, p=0.096), and any mental disorder (18.0% vs. 13.7%, p=0.225) were higher, while insomnia was lower (19.5% vs. 30.1%, p=0.008). PTSD was low overall (1.8% vs. 0.7%, p=0.333). Risk factors included female sex (p<0.001, cOR=0.362 for depression in males), younger age (p=0.004), unemployment (p=0.017), and prior trauma (p<0.001). COVID-19 symptoms (difficulty breathing) increased the risk of depression (p<0.001, cOR=2.828 [1.708-4.682]). Conclusion Hospitalization for COVID-19 increases the risk of depression and anxiety, modulated by demographic, clinical, and socioeconomic factors. Targeted interventions for vulnerable groups are essential.