Injections of Medical Insights

Aired on the series “The Surgeon’s Cut”, Twin to Twin Transfusion Syndrome (TTTS) is a prenatal condition in which twins share unequal amounts of the placenta's blood supply resulting in the two fetuses growing at different rates. TTTS is also deadly for the fetus. The unequal distribution of blood to each twin can cause one of the twins to receive an excess amount of blood. This exerts a greater pressure on the circulatory system, causing damage and likely death. Likewise, the other twin receiving insufficient blood form the placenta suffers from malnutrition and development problems. In complicated cases such as TTTS, minimally invasive surgery gives twins the best chance of survival. The surgery is known as endoscopic laser ablation. The surgeon inserts a laser fibre enclosed in a telescope and separates the blood vessel(s) that run from one twin to the other. Sources: https://www.hopkinsmedicine.org/health/conditions-and-diseases/twintotwin-transfusion-syndrome-ttts https://pub

  Binge-eating disorder is a serious eating disorder where one is unable to stop eating and consumes an unusually large amounts of food.  People with binge-eating disorder find it unable to stop eating even when uncomfortably full. They also feel compulsions to eat rapidly and non-stop.  This eating disorder often leads to obesity, and can result in a poor quality of life. Furthermore, there are many instances where it also leads to other mental illnesses such as depression or anxiety.  Therapies and medication are used to treat this illness. Anti-ADHD medications, anticonvulsants and antidepressants are prescribed to patients with such an illness. Sources: https://www.mayoclinic.org/diseases-conditions/binge-eating-disorder/symptoms-causes/syc-20353627 https://www.mayoclinic.org/diseases-conditions/binge-eating-disorder/diagnosis-treatment/drc-20353633

  Patients who suffer from nyctalopia, or more commonly known as night blindness, experience poor vision during the night or in poorly lit environments. It is a form of vision impairment and occurs as a symptom of numerous congenital (present from birth) and inherited retinal diseases or as a result of vitamin A deficiency. Vitamin A deficiency contributes to night blindness by making the cornea very dry, thus damaging the retina and cornea. As a result, the blood vessels running through these areas are affected. These veins carry neurons between the optic nerve and the brain. Hence, neurons die when the veins are damaged, and the brain does not receive visual information.  The effects of a damaged retina and cornea is exacerbated at night as the near absence of blue light renders one colour blind. This effect contributes to “night blindness”. Sources: https://www.webmd.com/eye-health/night-blindness https://www.optometrists.org/general-practice-optometry/what-causes-night-blindness/n

  Diabetic nephropathy is a serious kidney related complication of diabetes. About a quarter of patients with diabetes develop this condition.  Over time, diabetes causes damage to glomeruli in the kidneys. These glomeruli are responsible for filtering waste from the blood. Damage to glomeruli leads to decreased kidney function and eventually, kidney failure.  As a result of the reduced kidney function, other complications such as fluid retention, cardiovascular diseases such as stroke and anaemia may develop. If left untreated, the irreversible damage done to the kidneys will eventually require dialysis or kidney transplantation for survival.  To prevent the development of diabetic nephropathy, treatment of diabetes is essential. Other conditions such as high blood pressure, and obesity also have to be actively managed. In essence, a healthy lifestyle is imperative to prevent diabetic nephropathy. Sources: https://nkfs.org/kidney-failure/diabetic-nephropathy/ https://www.mayoclinic.or

  Astigmatism is a common vision problem caused by an error in the shape of the cornea. Astigmatism is a type of refractive error inside your eye, which has mismatched curves. Instead of having one curve like a round ball, the surface is egg shaped In a perfectly shaped eye, the cornea has a round curvature. A perfect curvature bends (refract) all incoming light equally to make a sharply focused image directly on the retina, at the back of your eye. However, in an egg or irregularly shaped cornea, light rays are not bent the same, which forms two different images. These two images overlap causing the image to superpose which results in blurred vision. Astigmatism may be present from birth, or it may develop after an eye injury, disease or surgery. Unlike Nearsightedness (myopia) or Farsightedness (hyperopia), astigmatism is not caused or made worse by reading in poor light, sitting too close to the television or squinting. https://www.mayoclinic.org/diseases-conditions/astigmatism/symp

  Fatal familial insomnia (FFI) is a very rare sleep disorder that runs in families. The disorder affects the thalamus, which controls emotional expression and sleep.  The main symptoms of FFI is insomnia, but there are further complications such as dementia and speech problems. Eventually, FFI causes death within a few years of the condition developing.  FFI is caused by a mutation in the PRNP gene, causing attacks on the thalamus. As this neurodegenerative disease is caused by a mutation in the gene coding for prions, it is considered a prion disease.  There is an even rarer form of fatal insomnia known as sporadic fatal insomnia. Ricard Siagan documented his mental deterioration as he suffered from this disease, which brought attention to this otherwise overlooked condition. Sources: https://www.bbc.com/future/article/20160118-the-tragic-fate-of-the-people-who-stop-sleeping https://www.healthline.com/health/fatal-familial-insomnia https://www.youtube.com/watch?v=R_YFluy_Tp8&fea

Horner’s syndrome is a condition where the sympathetic nerves on the face are damaged. 3 classic signs of Horner’s syndrome include miosis (constriction of the pupil), ptosis (drooping of the upper eyelid) and anhidrosis (absence of sweating of the face). It is a result of other medical problems such as stroke, tumor or spinal cord injury. Hence, treatment for the underlying issue may restore nerve function. The nerve pathway affected in Horner’s syndrome is divided into three groups of neurons called the first, second and third order neurons. These neurons lead from the hypothalamus of the brain through the spinal cord and finally along the facial skin and muscles of the iris and eyelids  Sources: https://rarediseases.info.nih.gov/diseases/6670/ horners-syndrome

  Atherosclerosis is a form or arteriosclerosis and refers to the buildup of fats and cholesterol in and on your artery walls. The plaque formed causes the arteries to narrow, blocking blood flow. It can also burst and lead to a blood clot.  Mild atherosclerosis does not have any symptoms, as symptoms usually present themselves when the arteries have become too narrowed and insufficient blood is supplied to organs or tissues. The symptoms also depend on where the atherosclerosis is located. If it is located in the heart arteries, the patient may experience heart pain. However, if it is found in arteries leading to the legs, the patient may feel pain when walking.  There are many complications associated with atherosclerosis, depending on which arteries are blocked. When arteries in the brain narrow, the patient may experience an ischemic stroke and when arteries in the heart narrow, the patient may have a heart attack.  The buildup of fatty deposits can be slowed or even reversed by ag

  Also known as “the stomach bug”, norovirus infects the patient’s stomach or intestines, causing stomach cramps, diarrhea or vomiting. It causes acute viral gastroenteritis, inflammation in the gastrointestinal system. It is the most common viral cause of gastroenteritis.  Norovirus spreads extremely fast, and it can be spread to others even when symptoms disappear.  Norovirus decreases the enzymatic activity in the intestines, causing malabsorption, inhibiting the absorption of fats. This is how norovirus causes diarrhoea.   It is transmissible via bodily fluids such as saliva and faecal material. It can also stay in surfaces and contaminate through them. Sources: https://www.cdc.gov/norovirus/index.html https://www.moh.gov.sg/diseases-updates/norovirus-gastroenteritis-(gastric-flu)

Neuropathy is damage of nerves which results in numbness, tingling, muscle weakness and pain in the affected region. Neuropathy often starts in the extremities but can also affect other parts of the body.  Neuropathy indicates a problem with the peripheral nervous system, where neurons are damaged . It can be caused by various conditions such as diabetes, trauma, and autoimmune disorders such as rheumatoid arthritis. In fact, neuropathy is present in 60-70% of people with diabetes.  Treatment of neuropathy first starts by identifying and treating the underlying problem, such as diabetes. Not all cases of neuropathy can be cured, and thus treatment is also aimed at controlling the symptoms and preventing further nerve damage. This is done through various medications to control pain and through physical and occupational therapies.  Neuropathy is one of the many complications associated with diabetes, and can even lead to limb amputation. Hence, it is important to maintain a healthy lifes

Attention deficit hyperactivity disorder (ADHD) is a condition with symptoms such as inattentiveness, impulsivity, and hyperactivity.  Although symptoms occur more often in childhood, both children and adults can have ADHD. There are 3 types of ADHD. These are predominantly inattentive, predominantly hyperactive/impulsive and combined.  ADHD brains have low levels of a neurotransmitter called norepinephrine. Norepinephrine is linked arm-in-arm with dopamine, which is the reward center of the brain.  The ADHD brain has impaired neurotransmitter activity in 4 regions of the brain. Attention, organisation, impaired communication and information processing.  For example, a deficiency in the Basal Ganglia causes interbrain communication and information to “short circuit”, leading to inattention and impulsivity.  Patients can also manage ADHD using medications such as amphetamine and methylphenidate. Sources: https://www.webmd.com/add-adhd/default.htm https://www.mayoclinic.org/diseases-cond

  A stroke occurs when the blood supply to part of the brain is interrupted, resulting in insufficient oxygen and nutrients for the brain cells. This causes the brain cells to die.  There are two main types of stroke: an ischemic stroke (caused by a blocked artery) or a haemorraghic stroke (caused by a burst blood vessel).  Ischemic stroke is more common, and occurs when the blood vessels become narrowed due to the build up of fatty deposits or by blood clots.  On the other hand, haemorrhagic strokes can result from many different factors, such as uncontrolled hypertension, aneurysms and trauma.  Strokes can occur at any time. Early action is paramount to effective treatment. Hence it is crucial to be able to spot the signs of stroke. After a stroke occurs, the patient may have trouble speaking, seeing and walking and may experience paralysis on one side of the body.  The patient should be rushed to the hospital immediately. Strokes can lead to temporary or permanent disabilities. Thes

Gastric bypass surgery was developed in the 1960s to aid patients with long-term weight loss and obesity-related medical problems such as diabetes, hypertension and high cholesterol .  The surgeon marks an area making up the new stomach and disconnects it. He then reconnects the new stomach and attaches it to the small intestine and seals up the break formed. This ensures that the patient will have an easier time feeling satiated after meals, preventing them from consuming more food, thus lowering their calorie intake.  This lessens the absorption of calories and nutrients which forces the body to tap into its reserves, leading to effective weight loss for patients.  Multivitamins and Calcium supplements are recommended alongside gastric bypass surgery to aid nutrient deficiency. Gastric bypass surgery is common amongst patients who reside in the upper extreme of the BMI scale. The procedure can easily help them lose over a 100 pounds.  Sources: https://www.youtube.com/watch?v=5J2ZbPoO

Prosopagnosia is a neurological disorder characterised by the inability to recognise faces. Instead, people with prosopagnosia can only recognise people based on contexts.  Prosopagnosia is hypothesised to be caused by damage to a fold in the brain, the right fusiform gyrus. The condition can be caused by stroke, injury to the brain or neurodegenerative diseases. However, it can also be congenital, and has been observed to be more common in those with autism.  There is no cure for prosopagnosia. However, therapy is used to help the patients use other visual or verbal cues such as height and voice, and their unique mannerisms to identify people. Sources: https://www.healthline.com/health/face-blindness#coping https://www.nhs.uk/conditions/face-blindness/ https://www.psychologytoday.com/us/blog/brain-babble/201309/prosopagnosia-why-some-are-blind-faces?amp

Unlike stroke volume, the heart rate is influenced by ‘electrical events’ and hence heavily regulated by chronotropic (rhythm) and dromotropic (electric) factors. Hence, stimuli of the autonomic nervous system and reflex control have a significant impact on patients’ heart rate.  The parasympathetic nervous system (PNS) decreases the heart rate by releasing the hormone acetylcholine to slow the heart rate. It also increases the atrioventricular node delay. In contrast, the sympathetic nervous system increases the heart rate in response to fight or flight situations such as stress and danger by releasing hormones such as catecholamines.   The ‘Bainbridge reflex’ is an example of reflex control which regulates the heart rate. Responsible for 40-60% of the increase in HR, the Bainbridge reflex increases the heart rate increases in response to a rise in atrial pressure. Sources: https://www.ncbi.nlm.nih.gov/books/NBK470455/ https://www.mayoclinic.org/healthy-lifestyle/fitness/expert-answe

Cardiac output is defined as the amount of blood the heart pumps throughout the circulatory system per minute. It is the product of stroke volume and heart rate.  Stroke volume is the volume of blood pumped out by the left ventricle of the heart during each systolic cardiac contraction. It is calculated by deducting the end-systolic volume from the end-diastolic volume. It is controlled by “mechanical events” and are hence heavily regulated by inotropic influences (changes in the body that alter the force or energy of the heart's muscular contraction).  Digoxin is a type of positive inotrope which increases the amount of calcium in myocytes (calcium stimulates the heart to contract). It may be given to patients who have had a recent heart attack, or to those whose hearts have been weakened after heart surgery. Beta-blockers, calcium channel blockers, and anti-arrhythmic medicines are negative inotropes which help the heart pump less blood per heart beat. This slows the nerve impul

Sciatica refers to pain that radiates along the sciatic nerve, which branches from the lower back through t he hips and buttocks and down each leg. The pain caused by sciatica can vary greatly, from a mild ache to excruciating pain. Usually, sciatica only affects only one side of the body.  Sciatica occurs when the sciatic nerve becomes pinched, usually by a herniated disc or a bone spur (overgrowth of bone).  More rarely, sciatica can be caused due to compression of the sciatic nerve by tumours. It can also be damaged by diseases such as diabetes. Most people recover fully from sciatica, even without treatment. However, sciatica can also cause permanent nerve damage. In order to prevent this condition from developing, one should exercise regularly and maintain proper posture. Sources: https://www.stkildaosteopathy.com.au/sciatica/ https://www.mayoclinic.org/diseases-conditions/sciatica/symptoms-causes/syc-20377435 https://www.spine-health.com/conditions/sciatica/what-you-need-know-abo

A cholesteatoma is an abnormal, non-cancerous growth that can develop behind the eardrum. It often develops as a cyst that sheds layers of old skin, causing the growth to increase in size and destroy delicate bones of the middle ear. This complication may affect hearing, balance and the function of facial muscles.  Cholesteatomas may be caused by a poorly functioning eustachian tube, which is a tube that leads from the back of the nose to the middle of the ear. This can result in a partial vacuum occurring in the middle ear, which pulls a section of the eardrum to the middle ear, causing a cyst that can become a cholesteatoma.  A cholesteatoma has to be removed surgically. Without surgical intervention, the cholesteatoma will continue to grow, resulting in further complications. Sources: https://www.healthline.com/health/cholesteatoma#prevention https://www.bmj.com/content/342/bmj.d1088