Yi-Kai Chang

School of Medicine, M.D.2001/Sep to 2008/JunCollege of Medicine, National Cheng Kung University (NCKU) Graduate Institute of Toxicology, National Taiwan University Ph. D. Candidates. 2023/ Mar~ present Visiting Scholar UCSD 2023 Visiting Scholar St Andrew War Memorial Hospital 2024

12th August 2025 - Asian Urology Residents' Courses (AURC)

Time Session
14:50
17:00
  • Weida LauSingapore Speaker An Indepth Discussion on Male InfertilityIn this lecture, we will look at the urologist role in the diagnosis and management of male infertility. We will take an indepth look at the timing of male infertility consult and the assessment of patient focusing on risk factors and the diagnosis of important etiologies of male infertility. Next, we address the interpretation of basic semen analysis and other essential tests for male infertility. Lastly, without being too exhaustive, we learn to manage specific management scenarios including varicocele, obstructive azoospermia, medical management of male infertility, and the issue of sperm retrieval. Low-Intensity Shockwave Therapy: Current Evidence and Applications in Erectile DysfunctionIn this lecture, we aim to understand the basic science behind the use of LiESWT for erectile dysfunction and summarize the evidence that supports the utility of LiESWT for ED. Next, the lecture will address the role of LiESWT in the present armamentarium for the management of ED, including selection of patients who will best benefit from the treatment. Lastly, the talk will touch on current trends in the use of shockwave treatment including the prevalence in the use of radial shockwaves that has gained popularity in some regions despite the lack of evidence for efficacy.
  • Yi-Kai ChangTaiwan Speaker A Practical Guide on Management for Sexual DysfunctionPlatelet-Rich Plasma (PRP) Therapy: Current Evidence and Applications in Erectile Dysfunction
  • Guo-Wei KaoTaiwan Speaker Correlation between Metabolic Syndrome and Men's Health
TWTC - 2F Conference Room 5

16th August 2025

Time Session
10:30
12:00
Erectile Dysfunction: Cardiovascular and Regenerative Advances
  • Chia-Chu LiuTaiwan Moderator
    Yu ChenTaiwan Moderator
  • Hung-Chieh ChiuTaiwan Speaker Erectile Dysfunction and Cardiovascular Health: Insights from the Updated Princeton Consensus1. PDE-5i exposure was associated with lower incidence of MACE, CV death, and overall mortality risk compared to non exposure and risk reduction correlated with PDE-5i exposure level. 2. Highlight of PDE5i and cardiac health in the 4th Princeton Consensus Conference. 3. ED symptoms precede clinically evident CVD by as long as 2 to 5 years. 4. ED management in patients taking nitrate-containing medications or substances. 5. Drug–drug interactions and CV safety of PDE5 inhibitors( real-world observation data) . 6. PDE5 inhibitors may have cardioprotective effects and might play a role in preventative cardiology in the future.
  • Bang-Ping JiannTaiwan Speaker Phosphodiesterase Type 5 Inhibitors (PDE5Is) and Their Role in Cardiovascular Health Phosphodiesterase type 5 inhibitors (PDE5Is) recommended as the first line treatment for erectile dysfunction (ED) in men. The increasing experience from PDE5Is use in ED along with a deeper understanding of cGMP-regulated mechanisms, gradually stimulated the scientific interest for further potential applications. PDE5Is were found to ameliorate pulmonary vascular resistance by augmenting NO-mediated vasodilation in the lungs. In animal models, PDE5Is were found to attenuate ischemia-reperfusion myocardial injury and reduce arrhythmia burden. In human studies, PDE5Is substantially improve myocardial contractility and clinical variables in patients with systolic heart failure. Meanwhile, PDE5Is have been shown to reduce pro-inflammatory mediators and improve markers of vascular aging in patients with ED. The pooled analysis of 16 studies demonstrated that the risk of major adverse cardiovscular events and all-cause mortality was reduced by 22% and 30%, respectively, in patients exposed to PDE5Is compared to controls. The use of PDE5Is provides important clinical benefits that extend beyond ED and include cardioprotective effects and improved survival after acute myocardial infarction.
  • Vinod K.VIndia Speaker Testosterone Therapy: Implications for Cardiovascular Health Sexual Function Preservation in MIS for BPH
  • Weida LauSingapore Speaker An Indepth Discussion on Male InfertilityIn this lecture, we will look at the urologist role in the diagnosis and management of male infertility. We will take an indepth look at the timing of male infertility consult and the assessment of patient focusing on risk factors and the diagnosis of important etiologies of male infertility. Next, we address the interpretation of basic semen analysis and other essential tests for male infertility. Lastly, without being too exhaustive, we learn to manage specific management scenarios including varicocele, obstructive azoospermia, medical management of male infertility, and the issue of sperm retrieval. Low-Intensity Shockwave Therapy: Current Evidence and Applications in Erectile DysfunctionIn this lecture, we aim to understand the basic science behind the use of LiESWT for erectile dysfunction and summarize the evidence that supports the utility of LiESWT for ED. Next, the lecture will address the role of LiESWT in the present armamentarium for the management of ED, including selection of patients who will best benefit from the treatment. Lastly, the talk will touch on current trends in the use of shockwave treatment including the prevalence in the use of radial shockwaves that has gained popularity in some regions despite the lack of evidence for efficacy.
  • Yi-Kai ChangTaiwan Speaker A Practical Guide on Management for Sexual DysfunctionPlatelet-Rich Plasma (PRP) Therapy: Current Evidence and Applications in Erectile Dysfunction
  • Chun-Hou LiaoTaiwan Speaker Regeneration Medicine in Urology - A Promising Future or Hoax?Regenerative medicine comprises therapeutic strategies aimed at restoring tissue structure and function, rather than merely alleviating symptoms. By deploying cells, biomaterials, bioactive molecules, or combinations thereof, these interventions stimulate the body’s intrinsic repair mechanisms. This paradigm extends beyond traditional symptomatic treatment, offering the potential for true self-healing and organ reconstruction—ultimately prioritizing cure over chronic disease management. Cell-based therapy has emerged as a promising intervention for various urogenital disorders, including erectile dysfunction (ED), bladder dysfunction, and male infertility. Current clinical research primarily focuses on mesenchymal stem cells (MSCs), investigating their safety, tolerability, and preliminary efficacy. Although early-phase studies suggest functional benefits—such as improved hemodynamics and tissue regeneration—most programs remain in preclinical or early clinical stages. A critical limitation remains the lack of standardization in MSC source, dose, and delivery route. Among alternative sources, human amniotic fluid-derived stem cells (hAFSCs) have shown particular promise. In preclinical models of cavernous nerve injury, hAFSCs demonstrated prolonged retention in penile tissue and in-situ differentiation into α-smooth muscle actin-positive corporal smooth muscle cells, effectively replacing damaged tissue and restoring function. These findings represent an encouraging step toward curative therapy. However, the mechanisms governing their in vivo behavior—such as engraftment, differentiation, and immunogenicity—will ultimately determine their clinical translatability and therapeutic stability. Whether cell-based approaches can evolve from experimental platforms into routine clinical care remains a central question. Platelet-Rich Plasma (PRP) Platelet-rich plasma (PRP) is an autologous biologic product enriched with supraphysiologic levels of platelets, growth factors, chemokines, and extracellular vesicles. Upon activation, PRP releases a bioactive cocktail that promotes angiogenesis, neuroregeneration, and antifibrotic remodeling—key processes in the restoration of urogenital tissues. In rodent models of cavernous nerve injury, PRP has been shown to preserve corporal sinusoidal endothelial cells and axonal scaffolds, while restoring erectile hemodynamics. Clinical studies further support PRP's safety in humans and report variable but promising improvements in IIEF scores following intracavernous injection. Nevertheless, the therapeutic response appears heterogeneous, likely influenced by patient factors, PRP preparation techniques, and injection protocols. Beyond ED, PRP has shown potential in other urologic indications such as stress urinary incontinence (SUI), interstitial cystitis/bladder pain syndrome (IC/BPS), and chronic pelvic pain, where it may contribute to tissue regeneration and symptom relief. However, broader adoption will require the establishment of individualized blood-quality metrics, standardized preparation methods, and randomized controlled trials demonstrating durable benefit. Emerging Regenerative Strategies Beyond cell-based and autologous biologics, a suite of innovative regenerative technologies is progressing from bench to bedside. These include: Energy-based devices such as low-intensity extracorporeal shock wave therapy (Li-ESWT), which promotes neovascularization and tissue regeneration via mechanotransduction pathways. Gene therapies, targeting dysfunctional or absent proteins in disorders like overactive bladder. Smart biomaterials, capable of delivering cells or bioactive molecules in a controlled, responsive manner. Extracellular vesicle (EV)-based therapeutics, which leverage cell-free vesicles derived from MSCs or urine-derived stem cells. These EVs carry signaling molecules (e.g., microRNAs, cytokines, growth factors) that mimic the paracrine effects of stem cells, offering a potentially safer and more scalable alternative to cell transplantation. In preclinical models of ED and bladder dysfunction, EVs have demonstrated the capacity to promote smooth muscle regeneration, nerve sprouting, and fibrosis reduction, with functional improvements comparable to stem cell therapy. Regenerative medicine has propelled the field of urologic tissue repair from theoretical promise to an early clinical reality. While substantial challenges remain—including the need for deeper mechanistic insight, protocol standardization, and regulatory clarity—the field is advancing rapidly. The convergence of cell therapy, PRP, EVs, and device-based modalities is creating a multifaceted toolkit for urologic regeneration. With continued scientific rigor, large-scale clinical trials, and interdisciplinary collaboration, regenerative medicine holds the potential to shift urologic care from chronic symptomatic management to durable, tissue-level cure.Stem Cell Therapy: Advancements and Clinical Insights for Erectile Dysfunction Treatment Erectile dysfunction (ED)—defined as the persistent inability to achieve or maintain an erection sufficient for satisfactory sexual activity—affects over 150 million men worldwide. While phosphodiesterase-5 inhibitors (PDE5is) remain the first-line treatment, many patients, particularly those with diabetes, age-related vascular decline, or neuropathy following radical prostatectomy, show suboptimal responses. Consequently, regenerative medicine—particularly stem-cell therapy—has gained interest for its potential to address the root causes of ED rather than merely managing symptoms. Stem-cell therapy offers a multifaceted approach to treating ED through neuroregeneration, angiogenesis, anti-apoptotic signaling, and fibrosis inhibition. Once introduced into the target tissue, stem cells can differentiate into specific cell types or exert paracrine effects via secretion of growth factors and extracellular vesicles. Among the various sources studied, bone marrow-derived mesenchymal stem cells (BM-MSCs), adipose-derived stem cells (ADSCs), and umbilical cord-derived MSCs (UC-MSCs) have been most extensively explored. Preclinical studies consistently demonstrate that MSC-based therapies enhance cavernous nerve regeneration, suppress fibrosis, and preserve endothelial integrity. In rat models of diabetes- or nerve-injury-induced ED, intracavernosal injections of ADSCs or BM-MSCs significantly restore intracavernosal pressure (ICP) and improve corpus cavernosum histology. Phase I/II clinical trials also support the safety and preliminary efficacy of stem-cell approaches. For example, in men with diabetic ED treated with autologous BM-MSCs, significant improvements in International Index of Erectile Function-5 (IIEF-5) scores and penile arterial flow have been reported without major adverse events. Similarly, ADSC therapy in post-prostatectomy ED has shown encouraging short-term results. However, large-scale trials are needed to clarify long-term efficacy, immune responses, and safety profiles. Human amniotic fluid stem cells (hAFSCs) represent a promising alternative, offering characteristics that bridge embryonic and adult stem-cell profiles. These include broad multipotency, high proliferation, and low immunogenicity—traits ideal for allogeneic use and neuroregenerative purposes. Notably, hAFSCs secrete potent regenerative mediators such as brain-derived neurotrophic factor (BDNF), vascular endothelial growth factor (VEGF), and insulin-like growth factor-1 (IGF-1), all of which support neurovascular repair and smooth muscle integrity. Our recent studies demonstrate, for the first time, that hAFSCs persist long-term in penile tissue and can differentiate into cavernous smooth-muscle cells, effectively replacing damaged tissue and improving erectile function even in chronic neurogenic ED models. Despite these advantages, our findings did not reveal in-vivo homing of hAFSCs to nerve injury sites or differentiation into neural tissue. This suggests a need for future studies to identify the specific microenvironmental cues required to induce such responses. Additionally, combining hAFSCs with platelet-rich plasma (PRP) may provide synergistic benefits—enhancing stem-cell homing, paracrine signaling, and in-vivo differentiation—thereby advancing a more effective, scalable, and safe therapeutic strategy.
TICC - 2F 201BC