Doctor-Reviewed Health Guides: Conditions, Procedures & Health News

A salivary gland scan, also called parotid scintigraphy, is a nuclear medicine test that shows how well the salivary glands make and release saliva. A radioactive tracer is injected into a vein, and a camera takes pictures. It helps evaluate dry mouth, swelling, blockages or stones. It takes an hour and is painless.

The Rinne test is a hearing screening that uses a tuning fork to compare how well you hear sound through the air versus through the bone behind the ear. Hearing it better through the bone may point to conductive hearing loss. It takes a minute or two and is painless. An audiogram is used to confirm hearing loss.

A muscle biopsy is a procedure to remove a small sample of muscle so it can be examined under a microscope. It helps diagnose muscle diseases such as muscular dystrophies and myositis. It can be a needle biopsy or an open biopsy. Soreness lasts 2 to 3 days, or up to a week after an open biopsy.

Molecular breast imaging (MBI) is a nuclear medicine breast test that uses a small amount of radioactive tracer to make fast-growing cells, such as cancer cells, light up on a special camera. It's used along with a mammogram, not instead of one, especially for women with dense breast tissue. The scan takes 20 to 40 minutes.

Intraoperative MRI (iMRI) is an MRI scan done during surgery that gives the surgical team a clear, up-to-date view of the area they're operating on. It's used most often in brain surgery, such as removing brain tumors. It helps surgeons confirm the whole tumor has been removed before closing, which can reduce the need for a second surgery.

EndoFLIP (functional lumen imaging probe) is a test that measures how wide the esophagus is and how easily it stretches under pressure. A thin catheter with a balloon and sensors is placed during an upper endoscopy under anesthesia. It helps diagnose achalasia, eosinophilic esophagitis and GERD. Stop eating and drinking at least 4 hours beforehand.

The antimitochondrial antibody (AMA) test is a blood test that looks for antibodies that attack the mitochondria inside liver cells. It's mainly used to help diagnose primary biliary cholangitis (PBC), an autoimmune liver disease that damages the tiny bile ducts. A positive AMA is strongly linked to PBC but isn't enough to diagnose it alone.

Coronary flow reserve (CFR) is a measure of how much blood flow to the heart can increase when it needs to work harder. A normal CFR is above about 2 to 2.5. A CFR below 2 suggests the heart's arteries can't deliver enough extra blood and is linked to a higher risk of heart attack and death.

Enteroscopy is a nonsurgical procedure that uses a long, thin scope with a light and camera to see inside the small intestine, which a standard endoscopy can't reach. It's used to find the cause of hidden GI bleeding, possible tumors or unexplained belly pain and to treat problems. Most people go home the same day.

Vein mapping is a painless ultrasound test that creates a map of the arteries and veins, showing their size, blood flow and any blockages. It's most often done before surgery to find healthy blood vessels, such as before coronary artery bypass surgery or creating a dialysis access. It uses no needles, dye or radiation.

A pharmacological nuclear stress test shows blood flow to the heart muscle at rest and under stress when you can't exercise enough on a treadmill. A medicine given through an IV makes the heart act as if it's working hard. Avoid caffeine, including decaf, for 24 hours before. The test takes about 3 to 4 hours.

A parathyroid scan is an imaging test that finds enlarged, overactive parathyroid glands, the four tiny glands in the neck that control blood calcium. It's done when blood tests show hyperparathyroidism and surgery is planned, so the surgeon knows which gland to remove. The most common types are a neck ultrasound and a nuclear sestamibi (MIBI) scan.

Carotid angiography is an imaging test that uses X-rays and contrast dye to show the carotid arteries, the main blood vessels in the neck that carry blood to the brain. It reveals narrowing or blockages. It's often done after a TIA or stroke, or when a carotid ultrasound is unclear. The test takes 60 to 90 minutes.

An MRI-guided prostate biopsy uses magnetic resonance imaging (MRI) to find suspicious areas in the prostate and guide needles to sample exactly those areas for signs of prostate cancer. It's used for a high PSA, an abnormal rectal exam or a suspicious MRI. Compared with a standard biopsy, it finds more clinically significant cancers and fewer harmless ones.

Urodynamic testing is a group of tests that show how well the bladder, sphincter and urethra store and release urine. Providers use them to find the cause of urinary incontinence, overactive bladder symptoms, a weak stream and trouble emptying the bladder. Testing takes 30 to 45 minutes, is generally painless and is safe, with a small risk of infection.

Pediatric hearing tests check how well babies and children hear, so hearing loss can be found early. About 1 to 2 in every 1,000 babies are born with hearing loss, and early diagnosis supports speech and language development. All U.S. babies get a newborn hearing screening. The tests are painless and take 30 minutes to 2 hours.

An oral food challenge (OFC) is a supervised test in which you eat slowly increasing amounts of a food you may be allergic to while a care team watches for a reaction. It's considered the gold standard for diagnosing a food allergy. Most reactions are mild and treated right away. Never try a food challenge at home.

A cardiac MRI adenosine stress test checks blood flow to the heart muscle at rest and under stress without exercise. Adenosine given through an IV widens the coronary arteries the way exercise would, and a heart MRI shows areas that don't get enough blood. Avoid caffeine for 24 hours beforehand. The scan lasts about 45 minutes.

Ambulatory heart monitors are wearable devices that record the heart's electrical activity at home for days, weeks or years. They help find irregular heart rhythms that come and go and may not show up on a standard EKG. Types include the Holter monitor, event monitors, patch recorders and implantable loop recorders. The main side effect is skin irritation.

An evoked potential test measures how quickly and strongly the brain and spinal cord respond to signals from the eyes, ears or skin. Electrodes on the scalp and body record the responses. It can find subtle damage in nerve pathways and is most often used to help diagnose multiple sclerosis. It's noninvasive and takes 60 to 90 minutes.

PERRLA is a quick eye check that stands for pupils equal, round, reactive to light and accommodation. A provider uses a light and a target to see whether the pupils are the same size, round, shrink in light and adjust when you focus near and far. Abnormal findings can point to eye problems or brain problems such as stroke.

FEV1 (forced expiratory volume in one second) is the amount of air you can forcefully blow out in the first second after taking the deepest breath you can. It's measured with spirometry. Healthy lungs push out more than 70% of their air in that first second. A low FEV1 can point to asthma, COPD or restrictive lung disease.

The corneal light reflex test, also called the Hirschberg test, is a painless way to check whether the eyes are aligned. A provider shines a light at the eyes and looks at where the reflection lands on each cornea. Reflections in different spots may point to strabismus. It's a screening test, so suspected misalignment is confirmed with other tests.

Fetal biometry is a set of ultrasound measurements that shows how big a fetus is and whether it's growing as expected for its gestational age. They're taken during routine pregnancy ultrasounds and reported as percentiles. A single unusual result doesn't mean something is wrong, and most of these babies are born healthy.