Education Corner

Understand about Macular degeneration Among common eye diseases, most people may have heard of cataracts and glaucoma, but are less familiar with age-related macular degeneration (AMD). “Macular degeneration,” “glaucoma,” and “cataracts” are the world’s three leading causes of blindness. With an aging population, the number of people suffering from AMD continues to rise, and in many countries, it has even become the leading cause of blindness among people aged 55 and above. As the saying goes, “Prevention is better than cure.” Let’s learn more about this condition to better protect our “windows to the soul.”   What is Macular Degeneration? The structure of the eyeball is similar to that of a camera. The pupil at the front of the eye works like a camera aperture, allowing light to enter. The lens focuses the light and projects it onto the retina. The retina functions like film—it receives light and converts it into images sent to the brain. Because the macula is located at the center of the retina, where photoreceptor cells are densest, it plays a vital role in vision. Many daily activities depend on central vision, such as reading, writing, recognizing faces, and driving.   What is Age-related Macular Degeneration (AMD)? Age-related macular degeneration (AMD) is a degenerative disease of the central retina (macula) caused by aging, damaging the macula’s photoreceptor cells and impairing central vision.AMD can be classified into two types: dry and wet. Dry AMDIn dry AMD, yellowish deposits called drusen accumulate under the retina in the retinal pigment epithelium (RPE). These deposits are waste materials excreted by photoreceptor cells and can disrupt their function, leading to gradual degeneration. Most early-stage patients have few or no noticeable symptoms, and vision loss tends to progress slowly. However, the condition should not be ignored, as it can develop into the more severe wet AMD. Wet AMDIn wet AMD, abnormal blood vessels grow under the retina in the macula. If these vessels rupture, they can cause bleeding and scarring, damaging photoreceptor cells. This form progresses quickly and can severely impair central vision—sometimes permanently destroying sight in the center of the field.Wet AMD can cause marked vision loss within as little as three months, or even within days in extreme cases. If sudden changes in vision occur, one should consult an ophthalmologist immediately without delay. Why Do I Have AMD? Multiple factors contribute to AMD development, but age is the strongest link—the older you are, the higher your risk. Studies show that smoking is associated with AMD progression, while quitting smoking can reduce risk. Genetics also play a role; those with close family members suffering from AMD are at higher risk. Other potential risk factors include diets high in saturated fats and cholesterol, hypertension, cardiovascular disease, and excessive sunlight exposure.   How Can I Check If I Have AMD? To diagnose AMD, in addition to routine vision and anterior segment checks, doctors will dilate the pupils to examine the back of the eye with an ophthalmoscope to assess the location, extent, and type of lesions.For precise classification, patients may undergo Fundus Fluorescence Angiography (FFA) or Indocyanine Green Angiography (ICGA), both of which involve injecting a dye into the bloodstream to observe retinal blood vessels.Another non-invasive test is Optical Coherence Tomography (OCT), which uses laser and light imaging to analyze the retinal and macular layers in detail.Besides professional exams, the Amsler grid test is a quick and simple self-assessment tool for detecting macular changes.   What Are the Treatment Options for AMD? Photodynamic Therapy (PDT)PDT combines medication with laser treatment. The patient receives an injection of a light-sensitive drug into the arm. This drug circulates through the bloodstream and binds to the abnormal blood vessels under the retina. The ophthalmologist then uses a low-energy (cold) laser to activate the drug, destroying the abnormal vessels and slowing vision loss. Studies show PDT can reduce the risk of significant vision decline and, unlike laser coagulation therapy, does not harm surrounding healthy tissue. Intravitreal Injection of Anti-VEGF DrugsThis is the current gold-standard treatment for wet AMD. Anti-VEGF (vascular endothelial growth factor) drugs block factors that promote abnormal blood vessel growth, reducing leakage and bleeding. Studies have shown that over 90% of patients receiving anti-VEGF injections maintain stable vision, and nearly one-third experience improvement. Because abnormal vessels may regrow, repeated monthly treatments are often needed until vision, macular thickness, and leakage are controlled. Intravitreal Injection of SteroidsSteroid injections can reduce damage to the blood-retinal barrier (BRB). The procedure must be carried out under sterile conditions with topical anesthesia and infection prevention measures in place. Laser Photocoagulation TherapyUsing laser heat, this treatment destroys abnormal fragile blood vessels under the retina, sealing and preventing further leakage, bleeding, or swelling. Because the laser can also damage nearby cells, it is only suitable for cases where the abnormal vessels are located away from the macular center. Otherwise, treatment could harm central tissues and cause vision loss.

What is hepatitis? Are there different types? Hepatitis is inflammation of the liver caused by infectious viruses. It can also result from viral infection, chemical exposure, drug abuse, certain medications, or immune system disorders.At least six different types of hepatitis viruses have been identified: A, B, C, D, E, and G.Most viral hepatitis cases are acute, but hepatitis B and C can become chronic, turning patients into long-term carriers. Hepatitis AA type of viral hepatitis that usually causes acute hepatitis and jaundice. Most patients recover completely, but in rare cases it can lead to liver failure or death. Hepatitis BA viral infection that may cause both acute and chronic hepatitis, and may develop into chronic liver diseases, including cirrhosis and liver cancer. Hepatitis CAn RNA virus that damages the liver. Some carriers of hepatitis C develop chronic hepatitis that scars the liver and may progress to liver cancer, similar to hepatitis B. Hepatitis DA virus that cannot replicate on its own and depends on the hepatitis B virus to reproduce within human cells. Therefore, individuals with hepatitis D are also infected with hepatitis B.The mode of transmission is the same as that of hepatitis B. One can be co-infected with both viruses simultaneously or infected with hepatitis D after becoming a chronic carrier of hepatitis B. Co-infection increases the risk of chronic hepatitis and cirrhosis. Hepatitis EA viral hepatitis caused by the hepatitis E virus, most commonly affecting adults. Pregnant women face higher risks of severe complications.The virus spreads through the digestive tract via contaminated food or water, particularly raw or undercooked shellfish polluted by feces from infected individuals. Person-to-person transmission is much less common than with hepatitis A. Hepatitis GA newly discovered virus whose severity and prevalence in Hong Kong have yet to be determined.   What are the symptoms of hepatitis? Most patients with hepatitis have no obvious symptoms. The symptoms and incubation periods of various types of hepatitis are listed below. Type  Symptoms  Incubation Period Hepatitis A Early stage: flu-like symptoms such as mild fever, fatigue, muscle pain, headache, loss of appetite, nausea, vomiting, upper abdominal discomfort, constipation, or diarrhea. Later stage: yellowing of skin and eyes, tea-colored urine. 2–6 weeks Hepatitis B Similar to hepatitis A, may include fatigue, nausea, abdominal pain, and jaundice. 6 weeks–6 months Hepatitis C Jaundice (yellowing of skin and eyes), tiredness, abdominal discomfort, and dark urine. 15–60 days (average 40 days) Hepatitis D Loss of appetite, nausea, pain in the right upper abdomen, jaundice, liver enlargement. Not specified Hepatitis E Jaundice, fatigue, abdominal discomfort, dark urine (tea-colored). 15–60 days (average 40 days) Hepatitis G General hepatitis symptoms: loss of appetite, nausea, right upper abdominal pain, jaundice, enlarged liver, tenderness in the liver area. Not specified   How can hepatitis be treated? Once diagnosed, patients should pay attention to maintaining a healthy lifestyle:Avoid alcohol and smoking, eat a balanced diet, exercise regularly, get enough rest, and avoid taking non-prescribed medications that could harm the liver. Type  Treatment  Hepatitis A No specific treatment, but some measures may help recovery: avoid drinking alcohol, get plenty of rest, drink adequate water, maintain good personal hygiene to prevent fecal–oral transmission, and take prescribed medication if symptoms worsen. Hepatitis B Take antiviral medication to suppress viral replication and relieve symptoms. Hepatitis C Take antiviral medication to suppress viral replication, avoid alcohol, and have regular liver check-ups. Hepatitis D No effective treatment currently available. Hepatitis E Most patients recover after 3–6 weeks of supportive treatment and rest. Hepatitis G No effective treatment currently available.   How can I prevent viral hepatitis? To prevent viral hepatitis, avoid high-risk behaviors. To reduce the risk of hepatitis A and E: Eat thoroughly cooked food, especially seafood. Avoid food sold by unlicensed vendors or hawkers. Wash hands thoroughly with soap before handling food, before eating, and after using the toilet. To reduce the risk of hepatitis B and C: Practice safe sex (use condoms correctly). Do not share syringes, sharp objects (like razors), or personal items (like toothbrushes). Handle sharp instruments with care to prevent needle-stick injury. Treat wounds properly. Ensure all reusable instruments are completely sterilized. Do I need a hepatitis vaccine? Since 1988, the Hong Kong government has provided free hepatitis B vaccinations for children under six years old.If you want to know whether you need a hepatitis A or B vaccination, consult your doctor for professional advice.

The Second Deadliest Cancer: Colorectal Cancer   Is colorectal cancer common in Hong Kong? According to the Hong Kong Cancer Registry of the Hospital Authority in 2009, colorectal cancer ranks second among all cancers in both incidence and mortality rates.Colorectal cancer mainly develops from intestinal polyps. The transformation process may take about 10 years and often shows no symptoms. Early detection and removal of these polyps can significantly reduce the risk of developing cancer.It is therefore recommended that people aged 50 or above undergo colonoscopy regularly. High-risk individuals—such as those with close family members diagnosed with colorectal cancer—should consider starting screening earlier (at age 40 or 10 years before the relative was diagnosed) and repeat it more frequently for prevention.   What is colorectal cancer? According to the Department of Health, colorectal cancer is a disease caused by abnormal growth of cells in the colon or rectum. These cancerous cells continue to grow and can spread to other parts of the body.Colorectal cancer is one of the most common cancers in Hong Kong. In men, it is the second most frequently diagnosed cancer. The risk increases with age, particularly among people over 50.   Who is at higher risk of developing colorectal cancer? High-risk factors include: A diet high in animal fat and low in fiber (such as insufficient fruits and vegetables) Lack of physical activity Family history of colorectal cancer or hereditary bowel diseases Chronic inflammation of the colon (ulcerative colitis) or the presence of polyps   What is a colonoscopy? A lower gastrointestinal endoscopy, commonly known as a colonoscopy, uses a flexible tube about 1.3 cm in diameter with a camera at its tip to examine the lower digestive tract.This includes the end of the ileum, cecum, sections of the colon, rectum, and anus. The test checks for tumors, polyps, inflammation, or bleeding. If abnormalities are found, the doctor can take tissue samples for laboratory testing, perform hemostatic treatment, or remove polyps. Because most colorectal tumors start as polyps, early detection and removal through colonoscopy can reduce cancer risk. Hence, colonoscopy is an effective preventive method for colorectal cancer.   Who should have a colonoscopy? Colonoscopy is recommended for individuals who: Are over 50 years old Have family members with bowel cancer Have had intestinal polyps Experience chronic diarrhea Notice blood in their stool Have changes in bowel habits (such as constipation or diarrhea)   How should I prepare for a colonoscopy? Before the procedure The bowel must be thoroughly cleansed before the examination so the doctor can clearly observe the intestinal lining. You must take laxatives as prescribed. Inform your healthcare provider if you have diabetes, high blood pressure, heart disease, kidney disease, are on a low-sodium diet, take long-term medication, or are pregnant/breastfeeding. Provide details of all medications taken, especially blood-thinning drugs or any history of allergies. Stop eating high-fiber foods three days before the procedure. Consume only clear fluids the day before the test. You may drink clear, fiber-free liquids up to four hours before the procedure. Arrive 30 minutes early. Bring a friend or family member along (do not drive yourself home afterward). If combined with an upper endoscopy, you must fast (no food or drink) for six hours beforehand. Medical staff will explain the procedure and its risks before you sign a consent form. During the procedure Remove all metal objects, jewelry, or dentures. Lie on your side with knees drawn up toward your chest. You will receive an intravenous sedative, so the procedure will take place while you are asleep. The process usually takes 30–60 minutes, depending on the complexity of the case. After the procedure You will rest in a recovery area until the sedative wears off. Because the medication may still affect you, it is safest to have a companion accompany you home. Avoid eating for 1–2 hours afterward. You may experience mild abdominal bloating or discomfort. If you experience bloody stool or severe abdominal pain, go to the nearest emergency department immediately.

How Should Nutritional Supplements Be Taken? Nutritional supplements—also known as dietary supplements, health supplements, or health foods—are concentrated nutrients extracted from food and beneficial to the human body. They come in various forms such as tablets, capsules, and liquid formulations. Taken appropriately, they can help replenish essential nutrients and regulate body functions.However, supplements and medications should not be taken together. Nutritionists recommend separating them by at least two hours to allow proper absorption in the digestive system.   What Is the Difference Between Functional and Nutritional Supplements? Supplements can generally be divided into two categories: functional and nutritional. Functional supplements focus on specific health benefits, such as antioxidant or immune-boosting effects. Common examples include quercetin (antioxidant), astaxanthin (antioxidant and immune support), and resveratrol (antioxidant). Nutritional supplements supply specific nutrients, such as multivitamins or single minerals. For instance, Vitamin B complex helps metabolism and supports the nervous system.   Which Type Should You Choose: Gummies, Powder, or Capsules? Supplements come in many forms—gummies, powders, and capsules.For example, probiotics are often made in capsule form to ensure the bacteria survive stomach acid and reach the intestines intact, unless patented technology allows other delivery forms.Powdered supplements are commonly used for general body support. Gummies are the mildest form and are suitable for children, the elderly, or those who have difficulty swallowing pills.Different supplements have different nutritional targets and optimal intake times.    When Is the Best Time to Take Them? 1. Water-soluble vitamins These include vitamins B1, B2, B6, B12, folic acid, biotin, and vitamin C.They dissolve in water and should not be taken with hot beverages, as heat can reduce their potency. Experts recommend waiting at least an hour after taking them before drinking hot water.Water-soluble vitamins are best taken before meals or on an empty stomach to avoid interference from food.Since B vitamins can boost energy and metabolism, avoid taking them at night to prevent sleep disturbances.   2.Fat-soluble vitamins These include vitamins A, D, E, K, and fish oil. They dissolve in fat and are absorbed through the intestinal wall, then processed by the liver and transported throughout the body. Because they require fat for absorption, take them after meals to improve uptake and utilization.These vitamins are stored in the liver and fatty tissues and are stable against light, heat, oxygen, and water. Deficiencies are rare, but excessive intake can lead to toxicity due to accumulation in the liver.   3.Calcium supplements Calcium helps reduce bone loss and promotes better sleep by calming the nervous system and relaxing muscles. Take it 2–3 hours before bedtime for best results.Calcium may interfere with the absorption of iron, zinc, and magnesium, so it should not be taken simultaneously with multivitamins, iron tablets, or foods high in oxalates (like spinach, water spinach, chives, or bamboo shoots).Because the intestines can absorb only about 500 mg of calcium at a time, divide your daily intake into two or three doses (morning, afternoon, or evening).   4.Glucosamine supplements Glucosamine can be taken with calcium, as both benefit bone and joint health. Pairing them with vitamin C further supports bone formation.   How should people of different age groups take supplements? Children and adolescents:It’s best to obtain nutrients from food. Multivitamins or DHA for brain development may be considered if needed. Adults:Requirements depend on lifestyle.Women may need iron; pregnant women should take folic acid, omega-3s, multivitamins, or probiotics under medical advice, and should avoid supplements that affect hormones (such as evening primrose oil).Men may benefit from supplements that support prostate health, such as lycopene and zinc. Elderly (65 and above):Focus on joint and bone health. Recommended supplements include glucosamine, vitamin D, and calcium.  

What is an ECG test? Can it detect hidden heart disease risks? Heart disease is one of the three leading causes of death in Hong Kong. Regular check-ups are one of the most effective ways to prevent it.An electrocardiogram (ECG) is a quick, painless test commonly used to assess heart health. It records electrical changes in the heart muscle as waveforms, essentially creating a visual record of the heart’s electrical activity. Through analysis of these patterns, healthcare professionals can understand basic heart information such as heart rate and electrical potential changes.ECG testing can be used both as part of a routine health check and as a preoperative heart assessment. The results help doctors diagnose various cardiac problems, including arrhythmia (irregular heartbeat), abnormal blood flow to the heart muscle, cardiac hypertrophy, congenital heart defects, and valvular diseases.ECG tests are broadly categorized into three main types: resting ECG, exercise ECG (treadmill test), and 24-hour Holter monitoring.   Which type of ECG should I choose? Resting ECG (ECG) The resting ECG is the most common method. It is quick, painless, and safe, taking only about 10 seconds to complete. The procedure is simple: metal electrodes are attached to specific points on the body to record electrical waves generated during heart muscle contractions.This test detects abnormalities in the heart while at rest, such as irregular rhythms or enlargement of heart chambers.   2. Exercise ECG (Treadmill Test) The exercise ECG evaluates heart function under physical stress. The test is performed while walking or running on a treadmill, during which medical staff record heart rate and ECG changes from rest to exertion and recovery.It takes approximately 10 minutes and can more accurately reveal issues such as myocardial ischemia (reduced blood flow), coronary artery disease, or other cardiovascular problems like blockage or infarction.   3. 24-hour Holter Monitoring (Continuous ECG) Because both resting and treadmill ECGs only capture heart activity at the time of the exam, they may miss irregular heart rhythms or transient symptoms. The Holter monitor addresses this by continuously recording heart activity for 24 to 48 hours (or longer) as the person goes about daily activities.This provides a more complete record for identifying intermittent heart conditions.   What should I be aware of during an ECG test? The resting ECG is painless and safe. You may feel slight discomfort when the electrode stickers are removed. The Holter monitor also involves no pain or risk. Electrodes attached to the chest with adhesive patches may cause mild skin irritation.Inform medical staff if you are allergic to any tape or adhesive materials. Avoid strenuous exercise, smoking, or consuming coffee, strong tea, and other stimulants within one hour before testing. Remove all items that may interfere with electrical signals—such as watches, metal jewelry, or nylon stockings—to ensure accurate results.

Is arrhythmia dangerous? Arrhythmia is one of the most common heart conditions in Hong Kong. It refers to any abnormality in the rhythm or rate of heartbeat. It is estimated that about 1% of Hong Kong’s population suffers from arrhythmia, most commonly atrial fibrillation and ventricular fibrillation.The risk increases with age. Although arrhythmia is not immediately life-threatening, if not detected and treated in time, the risk of stroke and heart failure is approximately five times and three times higher, respectively, than in people without it. Mortality risk also doubles.   What is arrhythmia? Arrhythmia refers to any abnormality in the heart’s rhythm or rate. In a healthy person at rest, the heart beats steadily between 60 and 100 times per minute. A resting heart rate lower than 60 beats per minute (bradycardia) or higher than 100 (tachycardia) is considered abnormal.Some people have a normal heart rate but irregular rhythm, which may suggest premature beats (extrasystoles) or atrial fibrillation.   What problems can arrhythmia cause? 1. Ventricular Fibrillation (VF) VF is a type of sudden cardiac arrest that can be fatal. Multiple parts of the ventricles beat chaotically, preventing the heart from pumping blood and oxygen to the brain and body.Without immediate cardiopulmonary resuscitation (CPR), the patient can die within minutes once the heart stops completely.   2. Atrial Fibrillation (AF) AF occurs when the atria quiver rapidly and irregularly, causing the heartbeat to become erratic (up to 200 beats per minute). It can last from a few seconds to several days.While not directly fatal, it can cause noticeable symptoms such as: Palpitations or irregular heartbeat Shortness of breath Dizziness or fainting Because blood flow becomes turbulent, clots may form in the heart. If a clot travels to the brain, it can cause a stroke.   What are the symptoms of arrhythmia? At rest, normal heart rates range from 60 to 100 beats per minute.When the heartbeat becomes abnormal, you may experience: Fatigue Shortness of breath Dizziness Chest tightness Chest pain Tiredness Fainting or loss of consciousness   Why do I have arrhythmia? Common risk factors include: Thyroid disorders Hypertension Ischemic heart disease Heart failure or valvular heart disease Side effects of medication Idiopathic causes (no identifiable reason)   How is arrhythmia diagnosed? Electrocardiogram (ECG): The primary diagnostic test. For long-term monitoring, a 24-hour ECG or event recorder may be used. Blood tests: To assess electrolyte balance and thyroid function. Further evaluations: Exercise ECG, CT coronary angiography, or electrophysiological catheter tests for detailed assessment.   How can arrhythmia be treated? Effective treatment depends on the underlying cause. Medication: Antiarrhythmic drugs are used to manage various irregular heart rhythms. Catheter Ablation: A common and standard minimally invasive procedure performed under local anesthesia. A cardiologist guides a catheter into the heart, locates areas causing abnormal electrical activity, and ablates them. It offers high success rates for many arrhythmia types. Implantable Devices: For slow heart rates with fainting episodes, a pacemaker may be needed. For abnormally fast heart rhythms or risk of sudden cardiac death, an implantable cardioverter-defibrillator (ICD) may be recommended.