GNMI FAQs

FAQs

Find answers to common questions about our services, appointments, and diagnostic imaging procedures.
MRIDoes MRI use radiation to produce images?+
No, MRI does not produce ionizing radiation like X-rays or CT. It uses strong magnetic fields and radio waves to generate images.
MRIWill I feel any side effects after my MRI?+
There are no known side effects after a routine MRI scan.
BMD / DEXACan I have a BMD test if I am pregnant or think I might be pregnant?+
No. Because fetuses are very sensitive to radiation, BMD tests are usually postponed until after pregnancy. If there is any chance of pregnancy, take a home test before your BMD appointment.
BMD / DEXACan someone stay in the room during my BMD test?+
No. Due to ionizing radiation, only qualified technologists may remain in the room during the scan.
BMD / DEXAWill I need to change into a gown for my BMD test?+
Usually no. Wear comfortable clothing without metal (no zippers, snaps, belts, metal accessories).
BMD / DEXAAre there height or weight limits for the scan?+
Yes. Max weight 350 lbs; max height 6'4".
BMD / DEXAWhat is a DEXA Total Body Composition scan?+
A low-dose X-ray test that assesses fat mass, lean mass, and bone mineral content. The scan takes about 6–10 minutes. More info: GNMI DEXA service.
BMD / DEXAHow do I prepare for a DEXA Total Body Composition scan?+
Wear clothing without metal. Avoid strenuous exercise beforehand. Do not attend if pregnant. Recent barium/contrast/radioisotope procedures can interfere—let us know.
GeneralDoes GNMI offer OHIP-insured services?+
Most medically necessary services are covered by OHIP. A small percentage are private pay if not medically indicated or if the patient does not have OHIP.
GeneralWhat is Whole Body MRI?+
A private pay screening exam (not OHIP-covered). Requires a requisition; we can help obtain one. Performed at GNMI Mississauga or Ajax.
GeneralWhy can't sonographers provide results?+
They are not physicians. Only your doctor can diagnose or advise treatment.
GeneralCan I bring my children to the appointment?+
Discouraged. Some tests use radiation and the exam room must remain distraction-free. Children cannot enter radiation rooms.
GeneralCan my report be sent to another doctor too?+
Yes. Tell reception and we will forward a copy.
GeneralCan I request a male or female technologist?+
You may request a preference; we will try to accommodate, but availability isn’t guaranteed.
GeneralDo I need a requisition?+
Yes. It’s a medical order—tests are performed only when requested by an authorized provider.
GeneralDoes it have to be a GNMI requisition?+
No. We accept valid requisitions from any licensed physician or authorized provider.
GeneralDo I need an appointment?+
Most tests require booking. General X-ray is walk-in; ultrasound/MRI/CT and specialized studies are booked.
GeneralHow do I book?+
Use gnmi.ca/book-appointment. If needed, SMS +1 (289) 274-0463.
GeneralWhen will my doctor get the report?+
Most routine reports are sent within 1–2 business days; complex cases may take up to 5 business days.
GeneralWheelchair user and cannot transfer independently—can you accommodate?+
We lack mechanical lifts. If you need only minimal help and can assist, we may accommodate; please bring a support person.
GeneralI already have a requisition—how do I book?+
Book at gnmi.ca/book-appointment or SMS +1 (289) 274-0463.
GeneralAre wait times long?+
Most routine procedures are scheduled within two weeks; MRI/CT or specialized ultrasound may be longer.
GeneralWhat services does GNMI provide?+
Varies by location: ultrasound, X-ray, mammography, bone density, MRI, CT, and more. See gnmi.ca/services.
MammographyCan someone come into the room with me during my mammogram?+
No. Because mammography uses ionizing radiation, only staff may be in the room.
MammographyCan I have a mammogram while breastfeeding?+
For acute issues, ultrasound is usually first. Routine screening is generally deferred ~6 months after breastfeeding ends.
MammographyCan I have a mammogram if I might be pregnant?+
Routine screening is avoided during pregnancy. With symptoms, ultrasound is first; further imaging per radiologist.
MammographyDoes cycle timing matter for comfort?+
The first 14 days after your period often feel less tender and more comfortable.
MammographyI have breast implants—can I be imaged?+
Yes. We use specialized techniques and extra views to visualize tissue around implants.
MammographyI was called back after my mammogram—does that mean something is wrong?+
Not necessarily. Recalls are common (about 10%) to obtain clearer/more detailed views.
MammographyIs a mammogram painful?+
Compression can be uncomfortable but shouldn’t be severely painful—tell the technologist if it is.
MammographyAny preparation needed?+
Avoid deodorant/antiperspirant/lotions on underarms or breasts the day of your exam.
MammographyWhat should I wear?+
A two-piece outfit (you’ll change from the waist up into a gown).
MammographyWhere can I learn about breast density?+
See Dense Breasts Canada: densebreastscanada.ca.
MammographyHow often should I get screened?+
OBSP screening: ages 40–75, typically every two years; requisition not required.
MammographyWhy avoid deodorant on the day?+
Residue can mimic micro-calcifications on images.
MammographyIs compression necessary?+
Yes—separates overlapping tissue for clearer images and lower dose.
MammographyCan men get breast cancer?+
Yes. Men with lumps or risk factors should consult their physician.
Nuclear MedicineAny side effects with Persantine?+
Temporary headache, flushing, shortness of breath, nausea or chest discomfort may occur (5–10 minutes). Aminophylline can reverse effects.
Nuclear MedicineDo I have to drink only water?+
Not strictly—total fluids matter and any caffeine restrictions specific to your test.
Nuclear MedicineStop medications before Part 2 (stress day)?+
Possibly. Bring an updated medication list to Part 1; staff will advise what to pause before Part 2.
Nuclear MedicineBone scan vs X-ray—what’s the difference?+
Bone scan shows bone metabolism/activity; X-ray shows structure/anatomy.
Nuclear MedicineHow long does a bone scan take?+
Part 1 ~15 minutes; Part 2 ~30–60 minutes depending on history and area imaged.
Nuclear MedicineDiabetic—how long to fast before stress day?+
Typically fast 3 hours before stress time; light breakfast and insulin 3–4 hours prior if directed by your physician.
Nuclear MedicineDo I need a driver?+
Usually no—you should feel fine to drive unless told otherwise.
Nuclear MedicinePrep for Part 1 (rest day) myocardial perfusion?+
No special prep unless instructed. Eat/take meds as usual; bring a full medication list.
Nuclear MedicinePrep for Part 2 (stress day)?+
Fast at least 4 hours; avoid caffeine 12 hours (including “decaf”). Avoid smoking/chewing gum 2 hours.
Nuclear MedicinePrep for a bone scan?+
No special preparation unless otherwise instructed.
Nuclear MedicineCould the stress test cause a heart attack?+
Risk is extremely low but not zero. Cardiologist/technologist monitor you; emergency equipment is on hand.
Nuclear MedicineWhat does myocardial perfusion assess?+
Heart muscle blood flow and coronary artery narrowing by comparing rest vs stress images.
Nuclear MedicineWhat happens during exercise stress testing?+
You walk on a treadmill with gradual increases while we monitor ECG, heart rate, and blood pressure (about 5–10 minutes).
Nuclear MedicineWhat happens during Part 1 (rest day)?+
Small tracer injection → wait ~30–45 minutes → imaging ~20 minutes under a gamma camera.
Nuclear MedicineWhat happens during Part 2 (stress day)?+
Stress via treadmill or Persantine → tracer injection → wait ~30–45 minutes → imaging ~20 minutes.
Nuclear MedicineWhat is Persantine stress testing?+
IV medication dilates vessels to mimic exercise—used if you cannot exercise adequately.
Nuclear MedicineWho decides treadmill vs drug-induced stress?+
Your referring physician recommends; our cardiologist confirms the safest approach before testing.
Nuclear MedicineWhy no exact time for Part 2 of a bone scan when booked?+
Timing depends on body area, disease factors, and camera availability. Return is usually 2–5 hours after Part 1.
Nuclear MedicineWhy not do both myocardial perfusion parts the same day?+
Allowing clearance of the first tracer improves image quality for Part 2.
Nuclear MedicineWhy drink extra fluid between bone scan parts?+
Helps clear unused tracer to reduce background and improve image contrast (aim for 750–1000 ml unless restricted).
Nuclear MedicineWhy is a bone scan in two parts?+
Time is needed for tracer to localize in bone tissue for accurate imaging.
Nuclear MedicineSide effects from tracer injection?+
Tracer injections are considered safe and typically cause no side effects.
Nuclear MedicineHow is the tracer cleared from my body?+
It decays naturally; hydration helps your body clear it faster.
Nuclear MedicineCan I cross the border after injection?+
Sensitive detectors may pick up tracer for up to a week. Request a medical note if traveling soon after.
UltrasoundDiabetic and fasting—how should I manage this?+
We try to schedule early morning. Tell the booking clerk you’re diabetic so we can time and advise appropriately.
UltrasoundPregnancy ultrasound—can I record the exam?+
No. Recording is not permitted. We can provide printed still images.
UltrasoundGall bladder removed—do I still need to fast for abdominal ultrasound?+
Yes. Eating introduces gas that degrades imaging; fasting improves quality.
UltrasoundMy bladder is painfully full—what do I do?+
Partially void ½–1 cup to ease pain; don’t empty completely unless instructed.
UltrasoundShould I take regular meds before ultrasound?+
Yes. If fasting, take with a small sip of water; if meds need food, take immediately after your scan.
UltrasoundWhat if I feel uncomfortable during the exam?+
Tell the sonographer immediately. Positioning/pressure can be adjusted; the exam can be paused or stopped.
UltrasoundWhy fast before abdominal ultrasound?+
Food increases bowel gas and contracts the gall bladder, both reducing visibility. Fasting improves imaging.
UltrasoundWhy avoid smoking or chewing gum beforehand?+
Both increase swallowed air and bowel gas, degrading images. Avoid for 2 hours prior.
UltrasoundWhy must my bladder be full for pelvic ultrasound?+
A full bladder is easier to see and pushes bowel aside for clearer pelvic views.
UltrasoundWhy change into a gown?+
To keep gel off clothing. If you choose not to change, we can proceed but can’t guarantee clothes stay dry.
X-RayIs an X-ray safe if I’m pregnant or might be?+
Non-urgent X-rays are usually postponed. If benefits outweigh risks, your physician will guide; alternatives without radiation may be used.
X-RayDo I need an appointment for an X-ray?+
No—standard X-rays are walk-in.
X-RayHow harmful is X-ray radiation?+
When clinically justified and performed properly, exposure is low and considered safe.
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