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

Videostroboscopy is an office test that uses a camera and a flashing light to show how the vocal cords vibrate when you speak or sing. The strobe light makes the fast vibrations appear in slow motion. It takes 15 to 20 minutes and needs no general anesthesia. It helps diagnose hoarseness, vocal cord lesions and vocal cord paralysis.

A BNP test (B-type natriuretic peptide test) is a blood test that measures a hormone the heart releases when it's stretched and working too hard. It helps diagnose heart failure, judge how severe it is and check whether treatment is working. A BNP below 100 pg/mL is generally normal. It's a simple blood draw with no special preparation.

A gallium scan is a nuclear medicine test that uses a small amount of radioactive gallium to look for cancer, infection and inflammation. Gallium is injected into a vein, and 1 to 2 days later a special camera takes pictures of where it has collected. The radiation dose is small, about the same as a few X-rays.

A dobutamine stress echocardiogram (DSE) is a heart test for people who can't exercise on a treadmill. Dobutamine given through an IV makes the heart beat faster and harder while ultrasound images are taken. Heart muscle that doesn't move normally under stress suggests narrowed coronary arteries. The test takes about an hour. Avoid caffeine for 24 hours beforehand.

24-hour ambulatory blood pressure monitoring (ABPM) uses a small, portable monitor and an arm cuff to check blood pressure automatically over a full day and night. It gives a truer picture than a single office reading, helping confirm high blood pressure and spot white coat hypertension. A normal 24-hour average is about 125/75 mm Hg or lower.

Immunophenotyping is a lab test that identifies the types of white blood cells in a sample by the markers, called antigens, on their surface. It's most often done with flow cytometry on blood or bone marrow. Providers use it mainly to diagnose and classify leukemia and lymphoma and to track how well treatment is working.

A discogram (discography) is a test that helps find which spinal disc is causing back or neck pain. Guided by live X-ray, a provider injects contrast dye into one or more discs and asks whether the injection reproduces your usual pain. It's usually considered only before surgery such as spinal fusion, and its use is debated.

Cerebrospinal fluid (CSF) analysis is a group of lab tests on the clear fluid that surrounds the brain and spinal cord. The fluid is usually collected with a lumbar puncture (spinal tap). It helps diagnose meningitis, encephalitis, multiple sclerosis, Guillain-Barré syndrome and bleeding around the brain. Some results are ready quickly, while others take about a week.

A TIBC (total iron-binding capacity) test is a blood test that shows how well the blood can carry iron. A typical normal range is 240 to 450 mcg/dL. It's usually ordered with serum iron and ferritin to check for iron-deficiency anemia or iron overload. You'll usually need to fast and skip iron supplements for 12 hours beforehand.

An electrolyte panel is a blood test that measures the main electrolytes in the blood, minerals that help control fluid balance, nerves, muscles and heart rhythm. It usually checks sodium, potassium, chloride and bicarbonate. Abnormal levels can point to dehydration, kidney disease, heart problems, diabetes or medicine side effects. It's a simple blood draw, usually with no fasting.

An MIBG scan is a nuclear medicine test that uses a radioactive tracer called iobenguane (MIBG) to find certain neuroendocrine tumors, such as pheochromocytoma, paraganglioma and neuroblastoma. These tumors absorb the tracer, so they light up on the camera. You take iodine drops beforehand to protect your thyroid, and scans are done about 24 hours after the injection.

A testicular self-exam (TSE) is a check you do yourself to learn how your testicles normally look and feel, so you can notice changes early. It takes a few minutes and is easiest in or after a warm shower. Most lumps are not cancer, but any new lump, swelling or heaviness should be checked by a provider promptly.

An incidental finding is something unexpected a provider sees on a test that was done for another reason, on imaging such as a CT scan, MRI or ultrasound. Common examples include lung nodules, thyroid nodules and kidney cysts. These findings are common and usually harmless. Your provider will decide whether one needs no action, follow-up or prompt treatment.

A FISH test (fluorescence in situ hybridization) is a lab technique that uses glowing DNA probes to find gene and chromosome changes in cells. It's widely used in cancer care, for example to check HER2 in breast cancer and to diagnose leukemias and lymphomas, and to find chromosome conditions before birth. Results usually take one to four weeks.

Capillary refill time (CRT) is a quick bedside test that shows how well blood is reaching the skin. A provider presses on a fingertip or toe until it turns pale, then counts how long normal color takes to return. Normal is about 3 seconds or less in adults. A slow refill can be an early sign of shock.

A nasopharyngeal swab is a test in which a trained provider passes a long, thin swab through the nostril to the back of the nose and upper throat to collect fluid and cells. It's used to test for COVID-19, flu, RSV and whooping cough. It's considered the most sensitive way to collect a sample for many respiratory viruses.

A contraction stress test (CST), also called an oxytocin challenge test, checks how a baby's heart rate responds to contractions to see whether the baby can handle the stress of labor. It's done only at 34 weeks or later. A negative result is normal. It can take up to two hours and is used less often today.

The patellar grind test, also called Clarke's sign, is a knee exam that checks whether pain around the kneecap comes from cartilage problems. The provider presses on your kneecap and asks you to tighten your thigh muscle. Pain or grinding is a positive result. The test can be positive in healthy knees, so it's combined with other exams.

A G6PD test is a blood test that measures glucose-6-phosphate dehydrogenase, an enzyme that protects red blood cells from damage. Low levels mean G6PD deficiency, an inherited condition that can cause hemolytic anemia. It's a quick blood draw, or a heel prick in babies, with no fasting. Testing during a hemolytic episode can give a falsely normal result.

The Wada test (intracarotid amobarbital test) is a test done before epilepsy or brain tumor surgery to find out which side of the brain controls language and how much each side supports memory. Medicine injected through a catheter puts one side of the brain to sleep for a few minutes while you're tested. Serious complications are rare.

Magnetoencephalography (MEG) is a painless, noninvasive test that records the tiny magnetic fields produced by the brain's electrical activity. It's mainly used to find where seizures start before epilepsy surgery and to map movement, sensation, language and vision areas before brain tumor surgery. It uses no radiation and no needles. The test takes about 1 to 2 hours.

Blood tests for coronary artery disease risk help estimate your chance of developing heart disease or having a heart attack. The core test is a lipid panel (total cholesterol, LDL, HDL and triglycerides). These tests don't diagnose heart disease on their own, but they help your provider judge risk and decide on lifestyle changes or medicines such as statins.

A videofluoroscopic swallowing study (VFSS), also called a modified barium swallow, is a video X-ray that shows how food and liquid move from the mouth through the throat and into the esophagus. It helps find the cause of trouble swallowing (dysphagia) and checks for aspiration. Results guide exercises and diet changes.

Endobronchial ultrasound (EBUS) is a type of bronchoscopy in which a thin, lighted tube with an ultrasound probe is passed through the mouth or nose into the airways. It shows lymph nodes and masses in the chest, and a needle can take biopsy samples. It's used to diagnose and stage lung cancer. You go home the same day.