KING EDWARD MEMORIAL HOSPITAL

Seth Gordhandas Sunderdas Medical College

Acharya Donde Marg, Parel,
Mumbai 400 012. India.
Tel.: 91-22-2410 7000 Fax: 91-22-2414 3435

General information about x rays and radiological investigations

Safety of x ray examinations

As practiced today, x-ray examinations are very safe. With improvement in the quality of the equipment used and radiation protection standards, no patient (with the exceptions described below) should avoid having an radiological examination for fear of harm by radiation.

There are however, a few situations where x-ray examinations may be more harmful.

For example – in young patients – whether they are boys or girls, additional protective measures will be taken by your radiologist to protect their reproductive organs.

X ray examinations performed during pregnancy may have adverse effects on the unborn child. This includes malformations of the fetus and increasing chances of childhood leukemia. These risks are maximal in the first three months of pregnancy and decrease substantially during late pregnancy. Therefore, in pregnancy, an x-ray examination will not be advised unless it is absolutely essential. If you are pregnant or likely to be pregnant, you should inform you doctor of this. Your radiologist will always ask for this and will advise of the pros and cons of the test that you have been asked to undergo. In case you have been accidentally exposed to radiation during pregnancy, and wish to know what is to be done (continue or terminate the pregnancy) please consult your radiologist. (You could also write to us with all details and we may be able to advise you on the best course of action).

Radiation produced by CT scans is the same as for x rays and rules are essentially the same as mentioned above for x rays.

MRI and Ultrasound examinations are, for all practical purposes, safe at all times and should not be a cause of concern even during pregnancy.

Radiographic contrast (dye) materials/injections

These are substances that are used by the radiologist during the course of certain radiological investigations to obtain clearer view of the various structures in the body. These contrast media which are popularly known as “dyes” are of various types and are used in standard radiological examinations, in CT scans and during MRI,

  1. Barium: This is one of the most well known contrast media used in radiology. Basically, it is a barium sulphate powder which is administered in liquid form of various consistencies It is used for investigations of the gastro-intestinal tract (gullet, stomach, small and large intestines). These agents are harmless; most patients find the flavour acceptable; at worst some patients may feel slightly nauseated on drinking the barium suspension. The barium is passed out of the body in the stools in a day or two; thus the stools may be of unusual color or consistency after a barium examination. This is normal and should not cause any anxiety. Barium liquid is also used an enema for the study of the large intestine.
  2. Iodine: Various organic compounds of Iodine are used for a variety of radiological investigations such as IVPs, angiographies, CT scans etc. These are mostly injected intravenously (for IVPs and CT scans) or intra arterially (for angiographies). Though these contrast agents are by and large very safe; occasionally, mild or rarely, serious side effects could occur following the injection of these contrast agents. Although, these side effects are unpredictable (no reliable pretesting is possible), fortunately they are uncommon and should not put you off from undergoing these investigations when a doctor advises them. However, if you are allergic to any drug or suffer from asthma or are an uncontrolled diabetic, your chances are developing a reaction are more. Your radiologist will carefully question your for these conditions and will then take adequate precautions to “minimize” the chances of a reaction occurring or treat if one should occur. Please be aware that it is usual to have a feeling of warmth and a metallic taste in the mouth when these agents are being injected. However, if you feel any other symptom such as nausea, vomiting, itching, or breathlessness, you should immediately bring this to the attention of the radiologist.

The following paragraph may sound a little technical,, but as it has important practical information on these injections, please read it carefully.

The iodine based contrast agents that we were talking about earlier, are broadly divided into two categories. The older “Ionic” variety and the newer “Non ionic” variety. The main difference is that the incidence of adverse reactions is vastly less with the newer “Non ionic” agents as compared to the older “Ionic” agents. The only reason the newer and safer “Non ionic” contrast agents are not universally used is that they are up to five times more expensive than the older “ionic” contrast agents. In case you suffer from any of the conditions mentioned above or even otherwise, if you do not want to take any risks, you could ask your radiologist to use the newer ” non ionic” medium- provided you are willing to pay additional cost for the same. Please note that even in the United States, the routine use of the newer: “Non ionic” contrast medium is not recommended as it is not felt to be cost effective in view of the relatively low incidence of adverse reactions even with the older “ionic” contrast injections.

Also, even with the newer “non ionic” contrast agents adverse reactions can occur but only very rarely.

  1. Gadolinium: Various compounds of Gadolinium are use as contrast injections during some MRI examinations. They are also used intravenously; however , much less frequently than the iodinated contrast is used for CT scans. They are very safe and adverse reactions are infrequent.

Barium studies

These are investigations performed using barium to evaluate the digestive tract (the gullet, the stomach, the small and large intestines). For all practical purposes, there are no side effects of these procedures and in most cases, you can resume normal activity and resume normal diet immediately after these investigations.

Barium swallow ( also known as an esophagogram) – for the evaluation of the esophagus (gullet)

Barium Stomach duodenum (SD) also known as the “Upper GI series” – for the investigation of the stomach and the upper part of small intestine.

Barium follow through (FT) also known as the “small bowel series” – for evaluating the small intestine.

Small bowel enema Selective and specialized visualization of small intestine

Barium enema for investigating the large intestine.

Barium swallow

This is a short, painless procedure which takes 10-15 minutes to perform. You may be asked to starve overnight for the procedure. You will be asked to swallow the barium liquid several times as the radiologists observes its flow under fluoroscopy (x ray screening). He will also take x rays as required in different positions. In some cases an intravenous injection may be given to relax the muscles of the esophagus to obtain good quality pictures.

You will get the final reports on the evening of the examination or on the following day.

Barium stomach-duodenum

This procedure is also similar to the barium swallow. You will be asked to report on empty stomach after overnight starvation. It is painless and takes up to 20 -30 minutes to perform, In addition to the barium; you will be asked to swallow a gas producing powder which will give better quality x ray pictures. In some cases an intravenous injection may be given to relax the muscles of the stomach to obtain good quality pictures. X ray pictures will be taken in different positions to visualize the various parts of the stomach and the duodenum.

You will get the final reports on the evening of the examination or on the following day.

Barium follow through

In addition to overnight starvation and reporting on empty stomach, often you will be asked to take laxative tablets on the night before the examination. When you report for the examination, you will be given one or more glassfuls of barium to drink and x ray pictures will be taken at periodic interval (hourly or so). Towards the end, your abdomen may be observed under fluoroscopy (screening) and more pictures taken. At this time, a enema tube may be passed and air instilled into your large intestine (this part of the procedure tends to be a little unpleasant though is essentially painless. You may even feel a very strong urge to pass stools , but you will have to control it for a few minutes).

The whole examination may take anywhere between an hour and 4- 6 hours (typically about 2 hours) depending on how soon the barium passes through the small intestine. Though not painful, the waiting may be a little boring. In some cases you may be asked to report for a “24 hour” film on the following morning. (At this time no further barium is given nor do you have to come starving) Pictures of the left over barium in the intestines is taken. You will get the final reports on the evening of the examination or on the following day.

Small bowel enema

When detailed information on the small intestine is required and especially when it is not available even after the barium follow through examination described above, you may be advised to undergo a small bowel enema. For this procedure again, you will have to report on empty stomach after overnight starvation. You may be asked to take laxative tablets on the night preceding the examination to clean your bowels.

For this procedure a long rubber tube is passed through your mouth (or sometimes through the nostril) and is guided by the radiologist into the small bowel under screening control. This part of the procedure takes about 10 minutes and can be unpleasant – especially when the tube is being passed through the gullet. In spite of this, the procedure is essentially painless. Once the tube is in place, the radiologist will inject barium and some other liquid through this tube ( when this is done , you will feel nothing) and x ray pictures of your small intestine are obtained. The whole procedure lasts about 30 -45 minutes.

You will get the final reports on the evening of the examination or on the following day.

Barium enema

This examination is performed for the visualization of the large intestine. For two or more days before the procedure, you will be asked to take purgative tablets to clean the large intestine. Some radiologists insist that on the day prior to the investigation, the patient take only light food or sometimes only liquids. All this is quite inconvenient but is essential to the performance of a good study and the more you cooperate the better the quality of the examination. On the morning of the procedure, most radiologists will allow their patients to drink fluid.

For the procedure itself, a thin suspension of barium is prepared and is then introduced into the large bowel through a enema tube. Following this air is pushed through the tube with the help of an pump. During this time, there is no real pain but patients experience varying degrees of discomfort and urge to pass stools.

Serial x-ray pictures are obtained under fluoroscopy to depict the various parts of the large intestine.

After the procedure, you will be allowed to pass stools and can resume a normal diet immediately.

The formal report is usually available on the day following the examination.

Intravenous Pyelography (IVP,IVU)

IVP stands for intravenous pyelography. This is also variously known as IVU (intravenous urogram or simply a urogram).

This procedure is done to evaluate the kidney, the ureter (the tubes that connect the kidney to the urinary bladder) and the urinary bladder

It is essential to have a clear picture of the abdomen before this procedure is done. Therefore most radiologists will prescribe that the patient take laxative tablets for two nights prior to the procedure. Also tablets to reduce the gas in the abdomen are also prescribed for 2-3 days prior to the investigation. This may be quite inconvenient but is essential to the performance of a good study and the more you cooperate the better the quality of the examination. You will be asked to starve overnight and report on empty stomach.

At first a “plain” x-ray of the abdomen is obtained. Amongst other things, this checks on how clean the abdomen is of feces and gas. Sometimes, if there is excessive feces or gas, the procedure may not be done and a further day’s abdomen cleansing tablets may be recommended.

Once the plain x ray film of the abdomen is seen to be satisfactory; a intravenous iodinated contrast injection will be give. This is the only painful part of this study.

After the injection, 8-10 x rays of your abdomen will be obtained for up to 1-2 hours. After the procedure is over, you can take normal diet and resume normal activities immediately.

Reports are usually available on the day following the examination.

Micturating cystourethrogram (MCU)

This procedure is almost always performed in men to study the urinary bladder and the urethra (the passage through which urine is passed).

Patients may be asked to refrain from drinking water for several hours before the procedure. A catheter (a thin hollow tube) is passed through the urethra into the urinary bladder. This is done under local anesthesia and may be mildly painful. Then the urinary bladder is filled with contrast medium and x ray films are obtained. One the films may be done while the patient is actually passing urine on a special x-ray table.

The procedure lasts about 30 minutes and the patient can resume normal activities immediately after the procedure. Sometimes, a course of oral antibiotics may be prescribed by the radiologist.

Dynamic retrograde urethrogram (DRU)

This procedure is done in males to look for narrowing of the urethra (the passage through which urine is passed).. No prior preparation is required. Iodinated contrast injection is made into the urethra after application of local anesthesia and X rays are obtained at this time. The procedure lasts around 10 minutes. No significant pain or only mild pain is associated with this procedure. You can resume normal activity immediately after the procedure. Reports are usually available the day following the procedure.

Ultrasonography and Color Doppler

Ultrasonographic examinations can be performed for virtually every part of the body; though are not very useful for evaluation of diseases of the brain and chest. They are most useful for diseases of the abdomen, during pregnancy and for evaluation of blood vessels (color Doppler).

In general all ultrasonographic examinations are painless; at most may cause mild discomfort and have no adverse effects. It is generally agreed that with ultrasonography, there is no danger to the unborn child. at any stage of pregnancy.

Except for ultrasonography of the abdomen, where prior preparation is required, no special preparation is essential for other ultrasonographic examinations. In some cases, patients may be instructed to drink plenty of water and not to pass urine for a couple of hours prior to ultrasonography of the abdomen.

Depending upon the type of examination, ultrasonography may take from 15 minutes to up to a hour especially if color Doppler studies are to be done.

Color Doppler is similar to ultrasonography, where the radiologist will evaluate diseases of the blood vessels with the use of ultrasonography.

Computerised Tomography Scan (CT Scan)

This procedure can be used to diagnose abnormalities of virtually any part of the body. This technique also uses x-rays to visualize various structures in then body, but in most areas, provides vastly more information than available from x ray films. The radiation safety concerns that apply to simple x-rays are the same for CT scans too.

Being essentially painless, the procedure needs no anesthesia; however, in cases of children and patients who are unable follow instructions, sedation or a short anesthesia may occasionally be necessary.

The procedure is essentially painless. However, for many CT scan examinations, intravenous injections of iodine based contrast is made and this could be a source of minor pain or discomfort. Also, in some cases, (especially abdominal scans), patients may be asked in addition to drink about two glasses (reasonably palatable) contrast medium before the commencement of the scan.

For plain CT scans (scans which do not need intravenous contrast injection), no preparation is required and these can be done at any time. If a contrast medium is to be injected, patients are usually asked to starve for 4-6 hors prior to the procedure.

The time required for most CT scans varies between 10 minutes and 45 minutes, and most of the time, all that the patient is expected to do is to lie as still as possible and follow simple breathing commands.

After the scan is over, the patient can resume normal activities almost immediately.

Depending upon the urgency of the procedure, reports can be made available within minutes of the completion of the examination. Routine reports are usually available by the following day.

CT myelography and CT cisternography

These are variations of normal CT scans ; but these procedures are seldom performed these days and are generally indicated only if MRI scans cannot be done for some reason.

And are indicated for diagnosis of the compression of nerve roots and spinal cord or for cases of cerebrospinal fluid (CSF) leak. For both these procedures, non-ionic, iodinated contrast medium is injected by a lumbar puncture. A lumbar puncture is done by inserting a needle under local anesthesia between the bones in the low back. It is a moderately painful procedure and may take up to 15 minutes. The patient has to starve for about 4 hours prior to the procedure. After the lumbar puncture is done, the contrast is injected into the fluid casing around the spinal cord. Once this is done, the patient will be examined in the scanner for about 15-30 minutes. After the scan is over, the patient will have to take complete bed rest for up to 24 hours. Many patients experience varying degrees of headaches for a day or two after this investigation. In spite of the pain and discomfort, the procedure is, by and large, safe.

Magnetic Resonance Imaging (MRI)

MRI most useful for investigating various disorders of the brain, the spinal cord, blood vessels, muscles and joints, the heart and blood vessels

This is a type of radiological examinations that do not use x-rays and hence there are no radiation “hazards”. For all practical purposes, the procedure is painless there are no complications with the procedure. However, if have had any metallic implants done in you at a time of a previous surgery (such as pace maker implants, nails and other hardware used by orthopedic surgeons, brain aneurysm clip etc); please bring this to the attention of the radiologist. He/she will then decide if it is safe for you to undergo this examination.

The equipment is similar to CT scanner in appearance; however, while lying inside the machine, some patients may feel claustrophobic and the examination may not be possible. For these patients there are the newer “open magnet” systems where there is no fear of claustrophobia.

Sometimes, the radiologist may inject contrast intravenously during the course of the MRI study. This often aids in the diagnosis.

As a rule no pre procedure preparation is required. Generally, the procedure lasts between 30 minutes and an hour and you will have to lie still during this type and follow simple breathing commands. The procedure being painless, no anesthesia is required, however, in case of small children and other patients who are unable to lie still, sedation or a short anesthesia may be required.

You can resume normal activities immediately after the procedure.

Depending upon the urgency of the procedure, reports can be made available within minutes of the completion of the examination. Routine reports are usually available by the following day.

Myelography

This is a procedure which is seldom performed these days. It is use to investigate symptoms arising out of compression of nerves and the spinal cord with in the spinal column.

By and large, this procedure has been replaced by MRI and CT scans.

For this procedure, non ionic, iodinated contrast medium is injected by a lumbar puncture. A lumbar puncture is done by inserting a needle under local anesthesia between the bones in the low back. It is a moderately painful procedure and may take up to 15 minutes. The patient has to starve for about 4 hours prior to the procedure. After the lumbar puncture is done, the contrast is injected into the fluid casing the spinal cord. Once this is done, the patient will be examined on an x ray table in varying positions (including a “head low position”) This takes an additions 15-30 minutes.. After the procedure is over, the patient will have to take complete bed rest for up to 24 hours. Many patients experience varying degrees of headaches and backache for a day or two after this investigation. In spite of the pain and discomfort, the procedure is, by and large, safe.

Reports are available on the day following the procedure.

Angiography

This procedure includes the study of blood vessels (arteries and veins) in the body.When, as is the most common case, arteries are studied it is called an arteriogram, (most of the time, the word angiogram is used synonymously with an arteriogram) and when the veins are studied it is called a venogram.Depending upon which particular artery is examined, these procedures have special names such as carotid angiograms – when vessels of the brain are investigated; coronary angiogram when the arteries supplying the heart are studied or a renal angiogram when the arteries of the kidney are looked at.In the current practice of angiography, small tubes called catheters ( they are about the diameter of a ball pen refill) and introduced into various blood vessels thru a small puncture of the artery in the groin. Sometimes, the entry point may be through blood vessels the upper limb (axilla, elbow or wrist), Through this tube, iodinated medium is injected and x rays are obtained. These x rays show up the state of your blood vessels.The following is typically what will happen when are to undergo an angiogram:A few days before the angiogram, blood tests may be done to make sure that the clotting parameters f your blood are normal. and that your kidneys are functioning normally.To avoid infection, hair in and around your groins will have to be shaved before the procedure. You will be asked to get admitted in a hospital on the night before or on the morning of the angiogram and will be expected to take nothing by mouth for 4-6 hours before the procedure.

In most situations, angiograms are done under local anesthesia. However, in cases of small children or adults who are unable to cooperate or in altered sate of consciousness, the procedure may be done under deep sedation or even general anesthesia.The moment you enter an angiogram room, you will see a bewildering array of equipment. There will also a be 5-6 persons including nurses, technicians, orderlies and of course the radiologist. Do not get intimidated by all this. To avoid infection, those performing the angiogram wall be dressed in as in operation theater. You will be asked to lie down on the x-ray table and an intravenous saline infusion may be started. Then a nurse wills cleanup your groin area with an antiseptic agent.The radiologist will then anesthetize the groin area a through which the angiogram is to be done (mostly on the right side; sometimes the left and occasionally both sides).The local anesthetic is injected with a very fine needle and the pain of this injection is just like any other ordinary injection you may have taken. After this, you will feel very little or no pain when the angiogram is being done. The radiologist will then puncture the blood vessel in the groin (remember – this will be essentially painless or mildly painful) and insert the catheter into the blood vessels – none of this procedure incites any pain. He will then put the catheter under x ray control into the desired blood vessel ( this is also painless) and inject some contrast medium and take x rays. During the actual injection of the contrast medium, for 5-10 seconds, you will feel varying degrees of warmth in the area being injected and rarely even mild pain. If non ionic contrast media are injected, there is no warmth or pain. During all this you will hear a lot of equipment noise, lots of talks between those present in the room (pay no heed to all this) and the table on which you are lying may be move up and down, sideways etcAn average angiogram lasts between 30 and 90 minutes.After the angiogram is finished, the catheter will be taken out and pressure will be applied on the puncture site to stop bleeding. This will last 5-10 minutes and is mildly painful. You will then be sent back to your hospital room. You should not move from bed or move the limb through which the angiogram has been done for at least 6 hours. Some radiologists may recommend bed rest for up to 24 hours. During this time, if there is any bleeding from the puncture site, do not get alarmed – apply firm pressure to stop the bleeding and ask for help. You will be allowed to take fluids after about 2 hours of the angiogram and then solids a couple of hors later. Reports will be available the following day.Thus an angiogram is a minor procedure, entails hospitalisation for 12-24 hours, and is mildly painful and generally risk-free.A venogram is a much simpler procedure, usually done without catheterization,. Normally it is done for lower limb varicose veins and an intravenous injection of contrast medium is made in the foot and multiple x rays are obtained. The procedure is minimally painful. The procedure lasts about 15 minutes and you can resume your normal activities immediately thereafter.

Angioplasty ,Stenting ,Embolisation:

Angioplasty is a procedure in which blocked blood vessels are opened up using catheters; so is stenting. Embolisation is the opposite – here abnormal or leaking blood vessels are closed with substances introduced through catheters. These and similar procedures where the radiologist treats diseases of blood vessels and other organs is known as interventional radiology and are generally performed as an alternative to surgery or in some cases as the only form of treatment where no surgery is possible.These are procedures which are similar to an angiogram in most respects. The main difference is – whereas an angiogram is used to diagnose blood vessel disease , angioplasty and embolisation are used to treat diseases of blood vessels or the organ that these blood vessels supply (brain, kidney, liver etc). The procedure of catheterization for both angioplasty , stenting and embolisation is similar to that of angiography. However, depending upon the specific area being treated and the specific condition for which the procedure is done, there will be variation in the technique, procedure time and complications. As the indications and the scope of these procedures is very vast; it is very difficult to generalize. If you have any specific questions, please send your queries to us.

Hysterosalpingography (HSG)

This procedure is done to visualize the female reproductive system, i.e.: uterus & Fallopian tubes. The indication is usually infertility.

The procedure is usually done on the 9th or 10th day after the onset of menses (when the chances that the patient may have conceived are the least).

The procedure is done without anesthesia; some patients may need some pain killers during the procedure as some may experience moderate pain.

Patients are instructed to shave their private parts (pubic hair) & are asked to bring one of their relatives along with them at the time of investigation.

The procedure involves cannulation of the cervix under direct vision with a cervical cannula & injection of radio-opaque contrast media into the uterus. Then multiple x-rays are taken to record the flow of contrast into the uterus and the tubes.

The procedure lasts about 30 minutes; patients may have some pain for a few hours after the procedure; but usually resume normal activities immediately thereafter. Patients may be asked to take a course of oral antibiotics after the procedure

The report will be available on the evening of or the morning after the procedure.

Dacryocystography

In a few cases of excessive watering of the eyes, a Dacryocystogram may be advised by the ophthalmologist.

This investigation is done to check the patency of the nasolacrimal duct, which is a small tubular passage which drains the tears from the eyes into the nose.

No preparation is required for the procedure. A small cannula (blunt needle) is introduced into a normally present hole on the lower eyelid. When this is done, there is no or very little pain or discomfort. Through this cannula, contrast medium is injected. There will be no pain when this injection is made; often there is a salty taste in the mouth as the contrast injection normally flows to the back of the mouth.

At this time one or more x ray films of the eye are taken.

The patient can resume normal activities as soon as the procedure is over. The average procedure time is around 15 minutes. The report is available on the following

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