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

Stereoelectroencephalography (SEEG) is a minimally invasive procedure that places thin electrodes deep inside the brain through tiny holes in the skull to find exactly where drug-resistant seizures begin. You then stay in an Epilepsy Monitoring Unit, usually about a week, while seizures are recorded. Results show whether epilepsy surgery or another treatment could help. Serious complications are uncommon.

Valgus and varus stress tests are hands-on exams that check the collateral ligaments on the sides of the knee or elbow. A valgus test pushes the joint inward to check the medial collateral ligament (MCL); a varus test pushes it outward to check the lateral collateral ligament (LCL). A positive result usually leads to imaging such as MRI.

A pancreas blood test measures two digestive enzymes the pancreas makes: amylase and lipase. It's mainly used to help diagnose acute pancreatitis in someone with severe upper belly pain. Levels around three times the normal limit are typical in acute pancreatitis. Neither test shows how severe pancreatitis is, so imaging is often needed too.

A sniff test is a real-time X-ray (fluoroscopy) of the chest that watches the diaphragm, the main breathing muscle, while you breathe and sniff quickly through your nose. If one side moves up when you breathe in, it suggests weakness or paralysis, often from a phrenic nerve problem. It takes about 15 minutes and uses very little radiation.

A pancreas ultrasound is an imaging test that uses sound waves to create images of the pancreas and nearby organs. It helps find pancreatitis, pancreatic cysts and tumors. The two types are a transabdominal ultrasound and an endoscopic ultrasound (EUS), which gives clearer images and allows a biopsy. You'll need to fast beforehand.

Fundus photography is a quick, painless test that takes detailed pictures of the back inside wall of the eye, the fundus, which includes the retina, macula, optic nerve and blood vessels. The photos help detect and monitor diabetic retinopathy, macular degeneration and glaucoma, sometimes before you notice symptoms. You may get dilating drops, which cause brief blurry vision.

The CA 19-9 blood test measures carbohydrate antigen 19-9, a tumor marker made in larger amounts by some cancers, most notably pancreatic cancer and bile duct cancer. It's used to support a diagnosis, check whether treatment is working and watch for recurrence. It is not a screening test, and a normal result doesn't rule out cancer.

A retrograde urethrogram (RUG) is an X-ray test that checks the urethra, the tube that carries urine out of the body, for narrowing, blockage or injury. A provider places a small tube at the tip of the urethra and injects contrast dye while X-rays are taken. It takes only a few minutes and may cause brief discomfort.

A throat culture is a quick, painless test that checks a swab from the back of the throat for bacteria or fungi, most often group A streptococcus, the cause of strep throat. Results usually take 2 days for bacteria and up to 7 days for fungi. A positive result for strep is usually treated with antibiotics.

Fetoscopy is a procedure that uses a thin, lighted camera (fetoscope) passed into the uterus to see and treat a baby before birth. It's usually done after 18 weeks of pregnancy. Doctors use it to treat serious conditions such as twin-to-twin transfusion syndrome and amniotic band syndrome. Risks include waters breaking early, preterm birth and pregnancy loss.

A mediastinoscopy is a minor surgical procedure that uses a thin scope with a light and camera to look at the mediastinum, the space between the lungs. Through a small cut above the breastbone, the surgeon removes samples of lymph nodes or masses. It's mainly used to stage lung cancer. Most people go home the same day.

An elbow X-ray uses a small amount of radiation to make pictures of the bones of the elbow joint. It's often the first test after an elbow injury or for pain, swelling or deformity. It can show fractures, dislocations and arthritis. Tendon problems such as tennis elbow don't show on X-ray and are usually diagnosed by exam.

A cardiac event monitor is a battery-powered device that records the heart's rhythm for weeks to catch symptoms that don't happen every day, such as palpitations, dizziness or fainting. Unlike a Holter monitor, which records for 24 to 48 hours, it covers a longer period. It's painless, and recordings are sent to your care team.

An LDH (lactate dehydrogenase) test is a blood test that measures an enzyme found in almost every tissue. A high LDH is a general sign of tissue damage. It helps detect and monitor hemolytic anemia, liver disease, muscle injury and certain cancers. LDH can't tell which tissue is damaged, so other tests are needed.

A bilirubin test is a blood test that measures bilirubin, a yellow pigment made when red blood cells break down. High levels cause jaundice and can point to liver disease, a blocked bile duct or faster breakdown of red blood cells. A normal total bilirubin is about 0.2–1.3 mg/dL. Very high levels in newborns need treatment, usually phototherapy.

A voiding cystourethrogram (VCUG) is an X-ray test that uses contrast dye to show the bladder and urethra while they fill and empty. It's used to check for vesicoureteral reflux, when urine flows backward from the bladder toward the kidneys. It's the most common test for reflux in children. It takes 30 to 45 minutes and needs no sedation.

A post-void residual (PVR) test measures how much urine is left in the bladder after you pee. It's used to check for urinary retention, when the bladder doesn't empty fully. It's usually done with a quick, painless bladder ultrasound. Roughly 50 to 100 mL or less is generally considered normal. Results are often available right away.

A venous extremity ultrasound uses sound waves to look at the veins in the arms or legs, mainly to check for blood clots such as deep vein thrombosis (DVT). It uses no radiation or needles and takes about an hour. If a clot is found, treatment with blood thinners usually starts right away.

The Self-Administered Gerocognitive Examination (SAGE) is a self-taken screening test for early signs of mild cognitive impairment and dementia. It has 12 questions and takes 10 to 15 minutes. Scores of 17 to 22 are normal, and 14 or lower suggests more serious problems. SAGE is a screening tool, not a diagnosis; a low score leads to further evaluation.

A prothrombin time (PT) test, reported with the international normalized ratio (INR), is a blood test that measures how long the blood takes to clot. It's mostly used to monitor the blood thinner warfarin. A normal INR is 0.8 to 1.1; for many people taking warfarin, the target is 2.0 to 3.0, but your provider sets your own target.

The multiple sleep latency test (MSLT) measures how quickly you fall asleep during a series of daytime naps and whether you enter REM sleep early. It's the main test for narcolepsy and idiopathic hypersomnia. It's always done the day after an overnight sleep study. You take up to five 20-minute naps, two hours apart.

A methylmalonic acid (MMA) test is a blood or urine test that measures a substance that builds up when the body doesn't have enough vitamin B12 or can't use it properly. Because MMA rises early, it can reveal a B12 deficiency even when the B12 level looks normal. A typical normal blood level is below 0.40 µmol/L.

A lymph node biopsy is a procedure that removes all or part of a lymph node so a pathologist can test it for cancer, infection or immune conditions. It's done when a swollen lymph node doesn't go away or looks suspicious, and to diagnose and stage cancers such as lymphoma. It's usually an outpatient procedure.

A lung biopsy (pulmonary biopsy) removes a small sample of lung tissue so a pathologist can examine it. It's most often used to diagnose and stage lung cancer, and also to diagnose sarcoidosis and pulmonary fibrosis. The four main types are bronchoscopic, CT-guided needle, thoracoscopic and open biopsy. The most common risk is a collapsed lung.