Cerebrospinal fluid (CSF) dynamics are increasingly recognized as central to brain waste clearance. Beyond the classical view of unidirectional CSF circulation, recent studies have identified the glymphatic system and meningeal lymphatic vessels as major complementary pathways. Glymphatic transport is driven by arterial pulsation, respiration, vasomotion, and strongly enhanced during slow-wave sleep. Advances in neuroimaging, including DTI-ALPS, EPVS quantification, contrast-enhanced magnetic resonance imaging (MRI), and ultrafast functional MRI, have enabled in vivo assessment of these mechanisms. Impaired glymphatic function has been linked to neurodegenerative and cerebrovascular diseases, highlighting its clinical relevance. Potential interventions range from lifestyle measures such as sleep optimization, exercise, and vascular risk control, to pharmacological and experimental strategies aiming to modulate CSF flow. These insights open new opportunities to target the glymphatic-lymphatic axis for the prevention and treatment of neurological disorders.

Purpose: To compare the anatomical and clinical outcomes based on the distance from the corneal limbus to the scleral tunnel in flanged intrascleral intraocular lens (IOL) fixation. Methods: We retrospectively analyzed the medical records of patients who underwent scleral fixation of flanged IOLs. Group 1 (54 eyes) had a distance of 2.1 mm from the corneal limbus to the scleral tunnel, and Group 2 (48 eyes) had a distance of 2.8 mm. We evaluated the best corrected visual acuity (BCVA), postoperative complications, IOL tilt and decentration, refractive prediction error (RPE), effective lens position, and iris-IOL distance. Results: The BCVA, postoperative complications, IOL tilt, and IOL decentration did not differ between the two groups (p > 0.05). The RPE showed a hyperopic shift in Group 1 and a myopic shift in Group 2 (Group 1: +0.24 ± 0.68 D, Group 2: -0.03 ± 0.43 D, p = 0.03). The iris-IOL distance was statistically longer in Group 1 compared to Group 2 (Group 1: 1.02 ± 0.40 mm, Group 2: 0.57 ± 0.32 mm, p = 0.02). The incidence of pupillary optic capture was significantly higher in Group 2 compared to Group 1 (Group 1; 0%, Group 2; 8.3%, p = 0.03). Conclusions It should be considered that a shorter distance from the corneal limbus to the scleral tunnel results in a postoperative hyperopic shift and reduces the incidence of pupillary optic capture when performing flanged intrascleral IOLs fixation.

Background/Aims: Gastric antral vascular ectasia (GAVE) is a rare but important cause of gastrointestinal (GI) bleeding. The clinical course of GAVE is not well-known, and recurrent bleeding from GAVE is a therapeutic challenge. Therefore, we investigated the clinical course of GAVE and identified the risk factors for bleeding from it. Methods: We retrospectively reviewed the records of patients diagnosed with GAVE using upper GI endoscopy at Asan Medical Center between January 2004 and December 2019 and evaluated the clinical course and risk factors for bleeding from GAVE. Results: Of the 348 patients (mean age, 62.3 ± 10.7 years; male, 62%), bleeding from GAVE occurred in 123 (35%) patients during follow-up (median, 17.3 months; interquartile range [IQR], 4.2–46.6). GI bleeding from GAVE was significantly associated with Child–Pugh class B or C liver cirrhosis (odds ratio [OR], 2.55; 95% confidence interval [CI], 1.57–4.16), chronic kidney disease (CKD) (OR, 2.77; 95% CI, 1.52–5.07), use of antithrombotic agents (OR, 2.34; 95% CI, 1.13–4.82), and involvement of the duodenal bulb (OR, 3.21; 95% CI, 1.76–5.86). Rebleeding occurred in 39 of 123 patients (32%), in whom CKD (OR, 2.55; 95% CI, 1.12–5.81) was significantly associated with rebleeding. Endoscopic hemostasis was most commonly performed using argon plasma coagulation, and the median number of endoscopic hemostasis performed was 2 (IQR, 1–3). Conclusions A careful follow-up for bleeding is needed in GAVE patients with liver cirrhosis, CKD, use of antithrombotic agents, and duodenal bulb involvement.

Purpose: Despite the global paradigm emphasizing earlier and more aggressive intervention for youth-onset type 2 diabetes mellitus (T2DM), metformin and insulin are the only drugs approved for Korean adolescents. We investigated the incidence of complications, changes in glycemic control during the transition period, the effect of second-line antidiabetic agents on glycemic control in young adults with youth-onset T2DM. Methods: Eighty-four patients diagnosed with T2DM at Seoul National University Children's Hospital between January 2001 and July 2023, before age 18 (47 males; mean age, 14 years) with available glycated hemoglobin (HbA1c) data from at least 2 distinct ages between 19 and 22 years old were retrospectively enrolled. Results: At the last follow-up (mean age, 24.9 years; median follow-up, 9.6 years), complications were found in 33.7% (nephropathy, 25.3%; eye disease, 20.6%), and 83% required insulin or second-line agents. During the transition period, HbA1c levels decreased from 8.2% at age 19 to 7.7% at age 22 (P<0.01), with greater improvements in females, those diagnosed before age 15, and those with HbA1c levels ≥7% at age 19. HbA1c level decreased significantly at 1 year after the addition of second-line medications (P=0.03) and at the last visit (P=0.03) compared with baseline. Conclusion Glycemic control improved during the transition period among youth-onset T2DM patients. Given the high incidence of complications and the beneficial effects of second-line agents on glycemic control, there is an urgent need to expand the range of approved second-line agents, along with broader insurance coverage in adolescence.

This video demonstrates the surgical technique of percutaneous endoscopic debridement and drainage (PEDD) for infectious spondylodiscitis performed under local anesthesia. Two representative cases are presented. The first case underwent transforaminal PEDD for L2–3 infectious spondylodiscitis, and the second case underwent combined transforaminal PEDD and drainage of a psoas abscess. In both cases, needle insertion was guided by C-arm fluoroscopy, followed by root block, discography, serial dilation, and insertion of a 3.7-mm endoscope. Under endoscopic visualization, necrotic disc material and infected granulation tissue were removed, and samples were collected for culture and biopsy. The procedure also enabled safe placement of a drainage catheter into the abscess cavity. Postoperatively, one patient improved with intravenous antibiotics after identification of Streptococcus constellatus, while the other was diagnosed with tuberculous spondylodiscitis and treated with antituberculosis therapy. Both patients showed gradual improvement in back pain and normalization of inflammatory markers. This video provides a detailed step-by-step guide to PEDD, highlighting its diagnostic and therapeutic advantages in infectious spondylodiscitis, as well as its educational value for surgeons learning full-endoscopic spine surgery.

The recent approval of trastuzumab deruxtecan for human epidermal growth factor receptor 2 (HER2)–low and HER2-ultralow breast cancer mandates an adequate assessment of these categories. Methods: Seven breast pathologists from the Breast Pathology Study Group of the Korean Society of Pathologists held an on-site expert consensus meeting. Fifteen sets of virtual whole slide images (WSI) of hematoxylin and eosin stain and HER2 immunohistochemistry were provided. The pathologists were given 60 minutes to submit their diagnosis of HER2 expression into null, ultralow, 1+, 2+, or 3+. Afterwards, in-depth discussion and consensus diagnoses were made by real-time visualization of the WSI. Results: After the consensus meeting, unanimous 100% agreements were seen only in five (33.3%) of the examined cases, which consisted of three 1+ cases and two 2+ cases. Two cases (13.3%) had mild disagreement, with only one pathologist’s disagreement. Of note, eight cases (53.3%) showed significant disagreement, defined by more than two pathologists’ disagreement. All HER2-null cases were reclassified as ultralow after consensus review, suggesting potential widespread underclassification of ultralow cases in clinical practice. Conclusions: Experts had significant discrepancies in interpreting HER2-low/ultralow status. It is important to assess if the distinction between HER2-low and ultralow is strictly required and if HER2-null breast cancer exists in reality.

This case describes a male with a history of type 1 autoimmune pancreatitis (AIP) who had a concomitant branch-duct intraductal papillary mucinous neoplasm under long-term surveillance. During follow-up, new high-risk radiologic features developed within the pancreatic cyst, raising concern for malignant transformation and ultimately leading to surgical resection. However, final histopathologic examination revealed recurrent type 1 AIP rather than malignant progression of branch-duct intraductal papillary mucinous neoplasm, a finding that represents an uncommon and diagnostically challenging manifestation. This case suggests that when new imaging changes are observed during surveillance of pancreatic cystic lesions, clinicians should consider not only malignant transformation but also the possibility of recurrence or coexistence of underlying diseases such as AIP.

Objective: Cyclin-dependent kinase 4/6 (CDK4/6) inhibitors combined with endocrine therapy (ET) constitute the standard systemic treatment for estrogen receptor-positive, human epidermal growth factor 2-negative (ER+/HER2-) metastatic breast cancer (MBC). However, treatment responses remain heterogeneous, highlighting the need for reliable prognostic markers. This study aimed to evaluate the prognostic significance of 18F-fluorodeoxyglucose (FDG) PET/CT findings in this setting. Materials and Methods: This retrospective single-center cohort study included patients with ER+/HER2- MBC who underwent18F-FDG PET/CT before initiating CDK4/6 inhibitors plus ET between 2018 and 2023. Maximum standardized uptake value(SUVmax), whole-body metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were measured. Progression-free survival (PFS) and overall survival (OS) were evaluated as the primary and secondary outcomes, respectively, using multivariable Cox models. PET parameters (SUVmax, MTV, and TLG) were analyzed as both continuous and dichotomized variables based on median values, adjusting for relevant clinical covariates. Results: Among the 374 patients, 82 (21.9%) presented with de novo metastatic disease, and 357 (95.5%) received CDK4/6 inhibitors as first-line therapy. In multivariable Cox analysis, all continuous PET parameters were independently associated with PFS (adjusted hazard ratio for SUVmax 1.05 [95% confidence interval 1.02–1.08]; log-transformed MTV 1.16 [1.08–1.25]; and log-transformed TLG 1.14 [1.07–1.23]) and OS (SUVmax 1.08 [1.04–1.11]; log-transformed MTV 1.24 [1.12–1.38]; and log-transformed TLG 1.22 [1.11–1.34]) with all P < 0.001. Results based on dichotomized PET parameters were similar to those obtained with continuous values: PFS (adjusted hazard ratio for SUVmax ≥ 7.6, 1.41 [1.08–1.85]; MTV ≥ 21.2 cm 3 , 1.41 [1.08–1.86]; and TLG ≥ 78.9, 1.51 [1.14–1.99]) with P ≤ 0.013 and OS (1.43 [1.01–2.04]; 1.84 [1.28– 2.66]; and 1.73 [1.20–2.50], respectively) with P ≤ 0.046. Conclusion Pretreatment 18F-FDG PET/CT parameters are independent prognostic markers in patients with ER+/HER2- MBC receiving CDK4/6 inhibitors with ET, supporting their potential utility in risk stratification.

Objective: This study aimed to evaluate the feasibility, safety, and oncologic outcomes of irreversible electroporation (IRE) using a clustered electrode in patients with locally advanced pancreatic cancer (LAPC). Materials and Methods: In this single-center prospective cohort study, 13 patients with LAPC (median age, 60 years; range, 48–78 years) underwent clustered electrode IRE between September 2022 and September 2024. Patient characteristics, procedural details, and clinical outcomes were recorded. Endpoints included technical success, procedure-related complications, overall survival (OS), and progression-free survival (PFS). Results: Tumors were located in the pancreatic head in four patients (30.8%) and in the body/tail in nine (69.2%). The median tumor size was 2.4 cm (1.5–4.0 cm), and vascular invasion was present in all patients. Technical success was achieved in all patients. Intraoperative IRE was performed in 11 (84.6%) patients, and 2 (15.4%) patients underwent percutaneous IRE. Gastrointestinal bleeding events as major complications occurred in two patients (15.4%) and, both were successfully controlled by embolization. No 60-day mortality was observed. At a median follow-up of 24.5 months (range, 9.9–33.4 months) after IRE, median OS and PFS from IRE were 20.1 and 14.5 months, respectively. Conclusion IRE using clustered electrodes for LAPC appears to be a feasible therapeutic approach, offering reliable technical success and acceptable safety. Survival outcomes are encouraging; however, larger, controlled studies are required.