A Family Doctor's Tale - AMBLYOPIA

DOC I HAVE AMBLYOPIA


Amblyopia, commonly known as ‘lazy eye’, is reduced visual acuity in one eye that appears normal on examination.

It usually develop during early childhood.

If left untreated, amblyopia will usually continue into adulthood.

The Causes of Amblyopia are:
1. Squint

Squint or misalignment of the eyes occurs when one eye is looking straight and the other is looking in another direction.
The vision from the deviating eye is suppressed.
The part of the brain that receives the vision from the deviating eye does not develop normally.
A severe reduction of vision in the deviating eye may occur.

2. Different refractive powers of the eyes

A significant difference in the degree of short-sightedness, long-sightedness or astigmatism between the two eyes may result in failure to form clear image in the eye with the greater refractive error resulting in Amblyopia.

3. Blurred vision in one eye

This occurs with:
1.An opaque cornea
2.Cataract
3.Drooping upper eyelids due to weakness of the muscles that lift the eyelids
4.Toxic causes such as arsenic, lead, smoking,vitamin B1 and B12 deficiency
5.Neurological causes are chiasmal lesions in the brain


Symptoms may include:
1.decreased vision in one eye
2.squint
3.drooping eyelid

Diagnosis and Early detection

1.Amblyopia in young children can only be discovered if vision in each eye is tested separately.

Treatment is usually more successful if amblyopia is detected early especially before the age of four.

2.regular eye and vision tests should be done by the family doctor, paediatrician or ophthalmologist.

Treatment

1.underlying conditions causing the ‘lazy eye’ such as refractive errors, drooping eye lid or squint should be treated.

2.The main purpose of treatment is to cause the part of the brain that reads images from the ‘lazy eye’ to work more harder to read images than the better eye.
The earlier the treatment is started, the better is the results.
Once the child is over 8 years of age, he/she may not respond well to treatment, resulting in permanently impaired vision.

Treatment can be given in two ways:
1.Eye Patch
 An opaque, adhesive patch is worn over the better eye for weeks to months. This treatment forces the child to use the weaker eye and stimulate the brain to read the images in the weaker eye.
The main problem with the eye patch is that no child likes to have his eye patched. Parents need to ensure that the eye patch is worn properly as advised by the eye doctor.

2.Atropine eye drops
In some cases where the child cannot tolerate eye patches, a drop of atropine is instilled in the stronger eye once a day to blur the vision temporarily in order that the child will prefer to use the ‘lazy eye’.

Prognosis:

Amblyopia if left untreated can lead to loss of vision in the ‘lazy eye’.

Even with treatment 1% - 2% of the population will remain amblyopic. This occurs especially if:
1.the amblyopic stimuli is excessive
2.detection of amblyopia is too late;
3.the child responds poorly to treatment.

Even with one good eye the child can go about his life provided he/she takes good care of the good eye and protect it from harm.

A Family Doctor's Tale - DOWN'S SYNDROME

DOC MY CHILD HAS DOWN'S SYNDROME

Down syndrome is a genetic condition in which the affected person is born with mental disability and characteristic features.

These characteristic features have been called mongolism with:
1.obliquely set eyes
2.short stubby nose
3.flattened facies
4.short stature
5.generalized muscular hypotonia


Most people with Down's Syndrome are not able to look after themselves because of their mental diability.

But many of them have gentle and endearing personalities.

There is no medical cure for this condition.

Causes of Down's Syndrome:
Chromosomes are tiny structures in our body cells which can seen only with a special microscope.
They contains the genes which determines the characteristics of a person.

A normal person has 23 pairs of matching chromosomes in each cell.
Each pair is different and given a number except for the sex chromosomes which are named XY in the male and XX in the female.

A person with Down's Syndrome has an extra chromosone no.21

Types of Down Syndrome:

There are  three genetic variations that can cause Down syndrome:
1.Trisomy 21 

the commonest type in which all the cells have an extra chromosome 21.Here something goes wrong during egg formation in the mother so that the mother has an abnormal egg with extra chromosomes no.21. The child will then get an extra chromosone no.21. The cause of this abnomal egg formation is unknown but occurs more frequency with the mother's age.

2.Translocation Down syndrome

happens when the extra chromosome 21  is attached to another chromosome. During cell division the embryo may get the attached chromosome and so have an extra chromosome no 21 and get Down's Syndrome.

3.Mosaic Down syndrome

a another form of Down's Syndrome in which only some cells have an extra chromosome 21.

Risk factors of getting Down's Syndrome are:
1.maternal age above 35 years.

Most cases of Down's syndrome are born to women aged 35 and above.

The risk of a woman above age 36 conceiving a child with Down syndrome is 1 in 350. The risk increases to 1 in 100 by the age of 40 and to 1 in 25 at the age of 45.

2.Mothers with one Down syndrome child have a 1 in 100 chance of having another child with Down syndrome.

3.Parents who are known to carry the translocated chromosome for Down syndrome can pass the abnormal gene to their offspring.

Symptoms of Down's Syndrome are:
Mongolian features:
1.distinct flat facial profile
2.Upward slanting eyes
3.Flat nose
4.Protruding tongue
5.Flat back of the head
6.Small statue
7.Poor muscle tone
8.Broad, short hands with short fingers and a single crease in the palm
9.dry skin
10.thin fine hair

Mental retardation
1.mental disability
2.unable to look after themselves

Congenital defects:
1.congenital heart disease
2.other birth defects

Screening tests are done for all pregnant women above 35 years of age and include:

1.Triple test - is a blood test done for older pregnant mothers above 35 years which measures specific proteins in the mother’s blood. This may indicates the possibility of Down's Syndrome

2.Nuchal translucency test is an ultrasound scan of the embryo at 10-13 weeks of pregnancy. It measures the width of the spinal cord at the back of the baby’s neck.

If the screening tests suggest a possible high risk of Down syndrome, then the following diagnostic tests may be performed to determine or confirm whether the baby actually has Down syndrome:

1.Amniocentesis. A small amount of the amniotic fluid is obtained through a needle inserted into the mother's womb after 16 weeks of pregnancy. This fluid contains cells shed from the baby and can be examined to see if the chromosomes are normal.

2.Chorionic Villous Sampling (CVS) involves obtaining some cells from the mother's placenta to examine the baby’s chromosones.It is usually done around the 14th week of pregnancy.

3.Percutaneous umbilical blood sampling (PUBS) involves obtaining blood from a vein in the umbilical cord after 18 weeks of pregnancy. The blood cells are examined for chromosomal defects.

Complications of Down's Syndrome are:

1.Heart defects.
2.Leukemia  
3.Infectious diseases such as pneumonia
4.Dementia often appear before age 40
5.intestinal obstruction,
6.thyroid problems,
7.hearing loss
8.poor vision.

Treatment of Down's Syndrome:

There is no medical cure for Down syndrome.
However, children with Down syndrome do benefit from medical help and early interventions starting in infancy which improve the life expectancy and quality of life.

Prevention of Down's Syndrome:

Down syndrome cannot be prevented.
1.genetic counselling in high risk translocation genetic group before considering pregnancy.

2.Coping and support from a team of doctors, teachers and therapists who can  provide the resources and support to  take better care of your child.

3.Joining a Down Syndrome support group and families who are dealing with the same problem

Prognosis:
1.A better understanding of Down syndrome and early interventions have improved the quality of life of children and adults with Down syndrome.

2.If there is no major complications such as heart disease and leukemia, a person with Down Syndrome may have a slightly shortened life span than a normal person.

A Family Doctor's Tale - CANCER SCREENING 5

DOC DO I NEED TO GO FOR CANCER SCREENING 5

Cancer screening - conclusion

H.Prostate Cancer

Prostate cancer is the third most common cancer in males in Singapore.


It is seldom seen in men less than 50 years of age.


Most prostate cancers are slow growing and may not cause symptoms or shorten life.

Majority of patients diagnosed with prostate cancer do not die from it.


Having said that, there are rare instances where the prostate cancer is aggressive and can cause death very fast.

Men who are at high risk of prostate cancer are those with:
1.Aged 50 years and above
2.family history of prostate cancer diagnsed below the age of 60 years of age

Cancer screening procedures for prostate cancer includes:
1.Digital rectal examination or DRE is a quick and reliable rectal examination of the prostate gland with a gloved finger through the rectum.


If the prostate gland feels enlarged, hard and nodular(lumpy), there is a possibility of prostate cancer unlike the smooth enlargement of benign prostate hypertrophy.


A prostate biopsy will then be needed to eliminate the prostate for cancer cells.


2.Blood test- tumor marker Prostate Specific Antigen(PSA) may be raised indicating a possibility of prostate cancer.


However raised Prostate Specific Antigen (PSA) may also be due to non-cancerous enlargement or inflammation of the prostate gland.

Prostate Specific Antigen therefore serves as a guide to the presence and severity of prostate cancer especially where prostate cancer seldom kill a person being slow growing.


Summary of Cancer screening:
a.Colorectal Cancer (above 50 years of age)
1.Yearly Fecal Occult Blood Test after the age of 50 years
2.5 years once Colonoscopy if there is a family history of colorectal cancer

b.Lung Cancer (all adult ages)
Yearly CT scan for lung cancer for chronic smokers and family history of lung cancer

c.Liver Cancer (all adult ages)
1.6 monthly Alpha feto-protein blood test for those with chronic hepatitis B, liver cirrhosis or hepatitis C


2.Yearly Ultrasound of liver for those with chronic hepatitis B, liver cirrhosis or hepatitis C

d.Prostate Cancer (above the age of 50)
1.2 yearly Digital Rectal Examination(DRE) for all men with a family history


2.2 yearly PSA blood test

e.Nasopharyngeal Cancer (above the age of 40)
1.2 yearly EBV IgA antibodies test


2.2 yearly nasoendoscopy

f.Breast Cancer (above age of 40)
1.Monthly Breast Self Examination (BSE)


2.2 yearly mammogram and ultrasound of the breasts


g.Ovarian Cancer (all ages above puberty 16 years)
1.Yearly pelvic ultrasound


2.Yearly blood CA 125

h.Cervical Cancer (all ages who had sexual intercourse)
2 yearly Pap's smear test and vaginal examination

CANCER SCREENING 4

DOC DO I NEED TO GO FOR CANCER SCREENING 4

Cancer screening :

F.Cervical Cancer

Cervical Cancer is the sixth most common cancer in women in Singapore but can be prevented and treated early if regular screening is done.

Women who are at high risk of cervical cancer are those with:
1.sexual intercourse at an early stage


2.sexual intercourse with multiple partners


3.history of sexually transmitted infections


4.infection with certain high risk strains of human papilloma virus (HPV)


5.weakened immune system such as HIV infection


6.prolonged use of combined oral contraceptive (birth control)pills

Cancer screening procedures includes:
1.Pap smear test should be done yearly in women who has sexual intercourse or abnormal vaginal bleeding.
The Pap smear test involve a simple procedure in which the doctor obtains some scraping from the neck of the womb or cervix to detect abnormal cell changes.
Early detection of cancer of the cervix means early treatment and cure.
Patients who had HPV vaccination should also continue to go for regular Pap smear every 3 years


2.Yearly vaginal examination and pelvic examination which involve the Pap smear

G.Nasopharyngeal Cancer

Nasopharyngeal Cancer or NPC is a common cancer of the head and neck region especially common in Chinese men between the age of 40-65.

People who are at risk of developing Nasopharyngeal Cancer or NPC are:
1.family history of nasopharyngeal cancer -common in Chinese males, less so in other races and females


2.Viral infection of the nose-Epstein-Barr (EBV) virus has been shown to be present in most cases of nasopharyngeal cancer

3.Smoking with its 40 or more toxic chemicals in cigarette smoke can stimulate abnormal cells in the nose to mutate and become cancerous

Cancer screening procedures of nasopharyngeal cancer includes:
1.Blood test-tumor marker EBV. Blood is tested for raised level of EBV IgA antibodies against Viral Capsid Antigen(VCA) and Early Antigen).
Patients with raised EBV IgA antibody have a higher risk of developing NPC.
If these antibodies are seen to rise significantly, there is an indication of possibility of NPC in which case an endoscope examination of the upper nose and nasal biopsy can be done to exclude NPC.


VCA IgA test is more sensitive than EBV but remains high for 6 months following a viral upper respiratory tract infection.


EA IgA test is more specific in diagnosing NPC but the levels are also high in cancers of salivary glands, lung and stomach.


2.nasoendoscopy for patients with family history of of nasopharyngeal cancer or NPC.