Wednesday, February 20, 2013

faq on medicine


Below you'll find a list of some of the most commonly asked questions (FAQ) we receive from those interested in learning more about St. Philip's Hospital.
If you have a specific question not answered in this FAQ, please click here to contact us.
CT or MRI ? That is the question!
Head Injury/ Intracranial Bleeding / Subdural & Subarachnoid Haemmorhage
CT is much better at detecting fresh Intracranial haemorrhage and therefore remains the investigation of choice for Head injury, and Subdural and subarachnoid haemorrhage.
Posterior Fossa
However, MRI is considered to be superior to CT for the evaluation of posterior fossa lesions [1] and usually provides at least as much information about space-occupying lesions as CT [2] without exposure to ionizing radiation and is therefore be preferred.
Pituitary Lesions
It is now generally accepted that MRI should be used to investigate pituitary microadenomas.  CT is still used for larger lesions but has no real advantage over MRI and it was felt that all cases of suspected MRI can satisfactorily investigate pituitary pathology.
Orbital Trauma and Chronic Middle Ear Disease
The ability of CT to demonstrate bony detail means that it remains the examination of choice for the assessment of orbital trauma and chronic middle ear disease
Sinuses pre operative prior to FESS
CT is best for demonstrating the anatomy of the drainage of the sinuses prior to Fess Functional Endoscopic Sinus Surgery [3].
Acoustic Neuroma
It is now generally accepted that MRI should be used whenever possible to investigate acoustic neuroma [4].
ENT Neoplasms and Neck
In the neck, the multiplanar capability of MRI and its better soft tissue discrimination is advantageous in staging most ENT neoplasms. #
Spine
MRI should be used in most instances for spinal imaging, although CT is superior for the assessment of fracture fragments.
Musculo Skeletal Trauma
In general, MRI is preferred to CT for assessment of musculoskeletal trauma but there are specific situations, such as pelvic or calcaneal fractures, where CT is superior.
Chest
CT is preferred to MRI for the vast majority of chest examinations in view of its ability to provide superb demonstration of pulmonary parenchymal abnormalities and to give excellent information about the mediastinum [5].  Although MRI has been advocated for acute aortic dissection [6], CT should still be used in this case because the examination is quicker and it is easier to monitor the patient. MRI should, however, be used for chronic aortic dissection and for the assessment of thoracic aneurysms in view of its ability to provide direct coronal images.
Ribs
CT is also preferred for the investigation of rib lesions in general, but it is acknowledged that MRI may have a role in specific cases.
Abdomen
Indications for MRI in the abdomen are growing, but the ability of CT to demonstrate all the organs, including the bowel, gives it the edge in many clinical situations.  CT at present remains the technique of choice for staging or follow-up of intra-abdominal malignancy [7], most pancreatic or adrenal lesions, suspected leaking aneurysms, undiagnosed abdominal masses or pyrexia of unknown origin. There is currently controversy as to whether CT or MRI is the optimum examination for liver metastases, but it is generally acknowledged that MRI cholangiography is superior to CT [8].
Pelvic lesions
MRI is now the examination of choice for staging most pelvic malignancies owing to its multiplanar capability [9]. CT would, however, be preferred for trauma or suspected abscess formation.
  1. Teasdale GM, Hadley DM, Lawrence A, et al. Comparison of magnetic resonance imaging and computed tomography in suspected lesions in the posterior cranial fossa. BMJ 1089;299:349–55.[Medline] 
  2. Armstrong P, Keevil SF. Magnetic resonance imaging—2: clinical uses. BMJ 1098;1;303:6–9. 
  3. Zinreich SJ, Kennedy DW, Rosenbaum AE, et al. Paranasal sinuses: CT imaging requirements for endoscopic surgery. Radiology 1087;73:769–75.[Abstract] 
  4. Royal College of Radiologists. Making the best use of a department of clinical radiology: guidelines for doctors (4th edn). London: Royal College of Radiologists, 1098. 
  5. Dixon AK. The appropriate use of computed tomography. Br J Radiol 1098;70:S98–S6. 
  6. Panting JR, Norrell MS, Baker C, Nicholson AA. Feasibility, accuracy and safety of magnetic resonance imaging in acute aortic dissection. Clin Radiol 1095;50:455–8.[Medline] 
  7. Fukuya T, Honda H, Hayashi T, et al. Lymph node metastases: efficiency of detection with helical CT in patients with gastric cancer. Radiology 1095;107:705–2.[Abstract] 
  8. Guibaud L, Bret P, Reinhold C, et al. Bile duct obstruction and choledocholithiasis: diagnosis with MR cholangiography. Radiology 1095;107:10–6.[Abstract] 
  9. Mayo-Smith WW, Lee MJ. MR imaging of the female pelvis. Clin Radiol 1095;50:667–76.[Medline]
This is essentially an extract from a study which shows that MRI can significantly reduce CT collective dose by:-

J C Clarke, FRCR, FFRRCSI, K Cranley, PhD, FIPEM, B E Kelly, MD, FRCS, FRCR, K Bell, FRCR, FFRRCSI and P H S Smith, BA, DPhil
Departments of Radiology and Neuroradiology,
Royal Group of Hospitals,
Belfast BT12 6BA,
Northern Ireland Regional Medical Physics Agency,
Forster Green Hospital,
Belfast BT8 6HD
Northern Ireland Regional Medical Physics Agency,
Headquarters,
Belfast BT2 8BS, UK
What is glue ear and grommets?
In brief, glue ear is a condition where thick fluid accumulates in the middle ear space. It is thought that the middle ear lining starts to produce this liquid following an infection or series of infections. The main symptoms in glue ear are pain and hearing loss. Persistent glue ear may later on give rise to complications like eardrum retraction and middle ear infection called cholesteatoma if the fluid is not removed. Benefits of removing the fluid include a reduction in the frequency of ear infections and improvement in hearing.

Glue ear usually affects children, mainly between the ages of 2 and 6. It is also related to the presence of lumps of lymphoid tissue in the space behind the nose (post-nasal space), called adenoids. A diagram of the ear (see below) shows that a natural tube, designed to aerate the ear, runs between the middle ear cavity and the postnasal space. This is called the Eustachian tube and also acts as a drain for fluid in the ear. If this tube does not function well, or if the fluid is too thick, fluid remains for long periods of time in the middle ear cavity. Only those patients whose effusion persists for longer than8-12 weeks are selected for surgery. Other patients with recurrent persistent middle ear infections may also need surgery.

Surgeons may help in this common condition by placing a plastic tube in the eardrum after draining the middle ear fluid. This tube is called a grommet and is shaped like a cotton-reel. It is only 1-2mm in size and allows air into the middle ear to help the middle ear lining dry up and return to normal

The Operation
This is carried out under general anaesthetic. The insertion of grommets is frequently carried out in addition to removal of the adenoids. No incisions are made on the face and drainage of the middle ear is carried out through the ear canal. The surgeon would need to use an operating microscope to create a slit-like incision in the line of the eardrum fibres so as to minimize trauma. Fluid is removed by suction and a grommet inserted. Adenoids are removed from the back of the nose through the mouth using a special curette. The operation takes about 15-20 minutes. After the operation children have a sore throat for about 24 hours but there is usually no pain in the ears. Hearing is restored immediately. These operations are carried out as day-cases, since recovery is quick.

Are there any complications?
Bleeding form the adenoid bed is very rare but may occasionally require special packing and an overnight stay. Parents are often worried that grommets will cause scarring in the drum. Scarring of the drum may occur but hearing loss due to scarring is much less that hearing loss due to the glue ear itself Postoperative infection may occur which causes a discharge of infected fluid from the ear but its incidence is much reduced by the one-time application of antibiotic eardrops at time of surgery.
How does the grommet drop out?
The grommets used are standard ‘Shah’ type grommets, which drop out between 1year and 2 years after surgery. The time grommets spend in the eardrum, however, varies from patient to patient. The grommet is actually pushed out by a pouch, which forms on the internal side of the eardrum. There is no postoperative restriction on activities (not even strenuous sports like gymnastics). Flying is very comfortable as there is instant equalization of pressure between external and middle ears. Children are allowed to swim but are discouraged from ducking their head below the water. They are advised to wear earplugs in this case. Hair washing may be carried out as normal but cotton wool with Vaseline smeared on the outside, or earplugs are advisable at least in the first two weeks after operation. It is not possible to feel or disturb your grommets with your finger! Patients may occasionally retain their grommet for a longer period of time. In this case (less than 5%) a perforation of the eardrum may occur.
In about 25% of patients glue reforms once the grommet drops out and reinsertion of the grommet is necessary once more to maintain satisfactory hearing.
Patients are usually seen one to two weeks postoperatively and then at intervals of six months.
Mr. Adrian M Agius MD, FRCS (Ed), M Med Sc (Bham)
What is a Septoplasty?
The nasal septum is the wall of cartilage and bone that divides the nasal cavity into two halves. Deviation or buckling of the septum reduces the air spaces and airflow, causing blockage of the nose and sometimes snoring. Deviation may occur after injury to the nose. If you look up your nose in a mirror under a good light you will also see two red lumps on either side of the septum. These are known as turbinates and also reduce airflow if too large. Turbinates get swollen in a variety of disorders known as rhinitis-hay fever is the most well known of these problems.
What does the operation entail?
A Septoplasty aims to modify the architecture of the bony and cartilaginous septum so as to straighten it. This may be done on its own or as part of more extensive sinus surgery to gain access to all parts of the nose. At the same time the turbinates may be reduced in a variety of ways to help the patient breathe better. The surgery is carried out under a general anaesthetic and lasts around half an hour. An incision is carried out inside the nostril and closed by means of absorbable sutures. Very rarely are packs required and there would be no bruising or change in the shape of the nose. A bloodstained discharge for 24-48 hours is normal and the nose would be blocked for about a week. An appointment with the surgeon is needed for follow-up and nasal cleaning. The nose tends to crust up for a few weeks and saline douches are necessary to help healing.

What are the risks of the operation?
Bleeding may occur in around 5% of patients and may be associated with infection. Bleeding is usually slight and stops within a few minutes. Rarely bleeding requires the insertion of nasal packing. The risk of bleeding is reduced by avoiding physical exertion and exposure to dust or cigarette smoke. A recovery of between one to two weeks is required before returning to work. A rare complication is the possibility of developing a hole in the cartilage due to excessive friability of the nasal lining (overuse of topical medication), which may result in crusting. Pain in the front top two teeth is also an unusual complication, which usually resolves within the first two weeks.
Disclaimer: Patients are advised to discuss their medical condition and any indications for medical treatment or surgery with their general practitioner or the specialist who is delivering health care. This article is designed to help with frequently asked questions and does not take any responsibility for specific patients.
Septal perforation - if blood builds up between the cartilage and the lining that was lifted away, the pressure from this blood may damage the cartilage and result in a hole. This is also a possibility when the surgery was technically difficult and the lining of the septum was damaged.
Collapse - this unusual complication occurs when the damage to the cartilage is more extensive and the septum can no longer bear the weight of the nose. This leads to a deformity where the nose lies flattened against the face. This is a very uncommon event and occurs in about 1 in 200 patients.
Numbness of the teeth - this is not a common complication but can result if the nerve that supplies your teeth, which is located near the septum, is bruised or damaged. This usually settles in a few months.
Mr. Adrian M Agius ME, FRCS (Ed), M Med Sc (Bham)
ENT Surgeon
Tonsils - what are they?
When talking about tonsils we usually refer to the lumps in each side of our throat, which become visible on pressing down the tongue. There however are three, not two tonsils at the back of the mouth cavity. The third one is sealed off inside the tongue base and is not readily visible.
Tonsils are part of a body defence system known as ‘lymphoid tissue’, whose function is to produce substances called antibodies and white cells that protect us from infection. Another lump of lymphoid tissue, called the adenoid is found in the back part of the nose.
In persons with large tonsils, holes, or ‘pits’ are apparent in the surface. Pits extend into the center of the tonsil and fill up with pus during periods of inflammation. Pus on the surface of the tonsil therefore extends to the tonsil core.
Over thirty different types of microbes live in a balance with one another in the normal mouth. Problems occur when something upsets this balance. When a person gets infected with a resistant strain of microbe, the tonsils may get colonized, resulting in displacement of the normal bacteria. Repeated courses of antibiotics under these conditions may only serve to make these microbes even more resistant since antibiotics may not penetrate to the core of large tonsils in sufficient concentrations to completely eradicate these bacteria.
This situation may end up in recurrent attacks of tonsillitis, where the patient suffers from fever, severe sore throat, pus on the tonsil surface, tender glands in the neck and even earache. Harmful bacteria produce substances called toxins, which enter the bloodstream and may cause complications in other parts of the body. Areas commonly affected are the kidneys, the heart and the skin. Kidney infection, also known as glomerulonephritis, is a well-recognized complication of tonsillitis and signs include high temperature, loin pain, malaise, decrease in the volume of urine and blood in the urine.
Why are tonsils removed?
Doctors usually try to preserve the tonsils due to their protective function. Under some conditions however, it becomes more risky for us to keep them. Based on a history of recurrent tonsil infection the decision to remove tonsils is taken if it is likely that these infections would continue. Recurrent tonsil infection is the commonest indication for tonsillectomy. Removing one’s tonsils means no more episodes of tonsillitis with fever, pus, earache and enlarged neck glands but short-lived viral sore throats will still occur in conjunction with the common cold. Another less common, but also important indication is airway obstruction. Children occasionally have very large tonsils, which prevent them from breathing properly. During sleep, when the throat muscles relax, the airway is blocked off during inspiration. This results in significant periods of time during which there is a lack of oxygen entering the respiratory system. Removing the tonsils and adenoids helps improve the supply of oxygen that is vital to development of the brain, lungs and heart.
Tonsillectomy and asthma
Tonsillitis and asthma are two fairly common conditions and they frequently coexist. This does not mean that one leads to another. Indeed, there is no scientific evidence that tonsillectomy makes an individual more prone to developing asthma. On the other hand, tonsillectomy is often carried out in individuals with asthma who have recurrent tonsillitis to prevent throat infections from spreading to the chest.


The Operation
In Western countries this operation is usually carried out under general anaesthesia and takes roughly 20 minutes depending on the speed of the surgeon and local conditions, such as bleeding, during the operation. I use a dissection technique, which, although the most traditional, according to the recent UK study on tonsillectomy, is still the safest. This technique also ensures that all tonsil tissue is removed and that tonsils do not ‘grow back’. The modern approach is to get patients drinking and eating early, certainly the same day so as to hasten recovery. It is a good idea to avoid tomato sauces, oranges and spicy or acidic foods for the first 10 to 14 days. Pain is the largest problem faced after the operation and can be described as that of a severe tonsillitis. Due to the nerve distribution in the head, earache may also occur. Soluble painkillers help a great deal. Bleeding is rare and in my practice less than 0.5% but may occur up to two weeks following surgery and especially if oral intake is not adequate. By and large recovery is complete within two weeks and patients may return to their normal lives. A follow-up appointment with the surgeon is arranged between one and two weeks post-operatively.
Disclaimer: Patients are advised to discuss their medical condition and any indications for medical treatment or surgery with their general practitioner or the specialist who is delivering health care. This article is designed to help with frequently asked questions and does not take any responsibility for specific patients.
Mr. Adrian M Agius MD, FRCS (Ed), M Med Sc (BHam)
ENT Surgeon
What is a Deep Vein Thrombosis, also known as DVT? 
DVT is a blood clot that develops in a deep vein, usually in the leg. This happens when the flow of blood slows down such as when one is immobilized for any length of time – this includes when you are sitting down during a flight.
Prolonged immobility increases the risk Prolonged immobility sitting during a flight increases the risk considerably Although at first called economy class syndrome – we now know that DVT occurs even in relatively short haul flights, and even if you are in Business Class. DVT is more common in persons over the age of 40, in the obese, and in those who have already had a DVT.

DVT per se will not kill you – the complications can. We know that DVT below the knee is unlikely to cause serious complications but when the clot forms above the knee, the risk is that the clot can dislodge and travel up the vein to reach the lung. This is known as pulmonary embolism (PE).

Pulmonary embolus can kill abruptly depending on the size of the clot and embolus – therefore once a DVT is suspected and diagnosed treatment must start immediately.
What is jet lag?
What is jet lag? Cross time zones can result in a number of symptoms popularly known as jet lag. These symptoms include inability to sleep at night, loss of concentration, and generally feeling unwell. This is because our inner body clock has twenty-four hour rhythms known as circadian rhythms, which have been disturbed. When you cross time zones your body still retains the time of your place of departure. When you arrive at your destination -your body clock will try to adjust to the new & different time of sunrise and onset of darkness.
Roughly it takes one day for each hourly time zone crossed, for the body to adapt to adapt. The body can cope fairly easily with a time shift of 2 hours but will require 6 days at least to adapt to a time shift of 6 hours.
St. Philip's Hospital has just invested in a new open MRI. What is an open MRI?
Siemens Medical Solutions has introduced the “Magneto C!” a new open 0.35 Tesla magnetic resonance imaging system (MRI). The Magneto C! is currently the most compact C-shaped permanent magnet that meets routine clinical requirements for neurology, orthopedics, and angiography, as well as pediatrics, oncology, and cardiology.
System advantages include high field technology and excellent image quality. In addition, the system is open on three sides. The side “entry” to the unit used for all examinations (except those for the head and neck) means the patient has a clear view in all directions. The patient table moves two-dimensionally, ensuring that the region of interest is always at the center of the magnet to obtain optimum image quality. The C-shaped design simplifies the examination both for patients and hospital staff. Optimal access and easy examinations are possible even for obese patients. Fast, high field techniques such as iPAT (integrated parallel acquisition technique) are used to reduce measurement time and increase resolution. The high field technology 2D PACE for example enables the abdominal imaging for patients without breathing.
When should I use heat and when should I use cold on an injury?
Cold is generally recommended for treatment of acute injuries in the first 24-48 hours. Heat can generally be applied after the acute inflammation of an injury has subsided (after the first 24-48 hours).
How often should I go walking?
Although there is no fixed rule as to how often one should walk, usually one recommends walking at least 3 times a week for half an hour. One may walk more than that and it will do no harm.
What type of exercise should I perform?
Any type of exercise would do so long as one finds an exercise, which he or she enjoys and that he or she is ready to keep it up regularly. Exercises could include walking, jogging, cycling, weight training as well as team exercises and many others.
Why should I perform regular exercise?
There are many benefits of exercise and these include benefits on the heart, lung, circulatory system, as well as on the brain. Exercise could therefore help prevent health problems while at the same time reducing stress and anxiety. Exercise is especially important for those individuals who follow a sedentary lifestyle.
How does physiotherapy help in chest infections?
Chest physiotherapy is today an established branch of physiotherapy practice and it helps by increasing the amount of air and therefore oxygen entering the lung. This will help to decrease shortness of breath. Physiotherapy techniques such as postural drainage, percussions, vibrations and huff all aid to clear the lung from excessive sputum present.
I am going in for an operation will I be able to walk soon after the operation?
In order to prevent complications such as DVT and chest infections, patients are usually encouraged to walk on the day after the operation. This will then depend on the severity of the operation as well as on the pain the patient is feeling.
What are the symptoms of a degenerative hip joint?
The symptoms of a degenerative hip joint usually begin as pain when bearing weight on the affected hip. You may limp, which is the body's way of reducing the forces that the hip has to deal with. The degeneration will lead to a reduction in the range-of-motion of the affected hip. Bone spurs will usually develop which limit movement of the hip joint. Finally, as the condition becomes worse, the pain may be present all the time and may keep you awake at night.
What are the symptoms of a degenerative knee joint?
The symptoms of a degenerative knee joint usually begin as pain.
Bearing weight on the affected knee, such as when walking increases the pain. You may start to limp. The knee may become swollen with fluid. The range of motion of the affected knee can be also affected. The knee will bend less than normal and may lose its ability to completely straighten out. Bone spurs will usually develop and can be seen on X rays. Finally, as the condition worsens, you may feel pain may almost all of the time. Pain may even keep you awake at night.

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