AOBNM Nuclear Medicine flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Tc-99m physical half-life

Approximately 6 hours; emits a 140 keV gamma ray, making it the most commonly used radionuclide in diagnostic nuclear medicine imaging.

Effective half-life formula

1/Teff = 1/Tphysical + 1/Tbiologic. It describes the combined physical decay and biologic clearance of a radiopharmaceutical from the body.

Mo-99/Tc-99m generator

Device producing Tc-99m from Mo-99 decay; transient equilibrium means eluted Tc-99m activity approaches but does not exceed Mo-99 activity.

Positron emission tomography physics

Positron annihilation produces two 511 keV photons emitted at approximately 180 degrees; coincidence detection localizes the annihilation event along the line of response.

F-18 FDG uptake mechanism

Glucose analog taken up by glucose transporters and phosphorylated by hexokinase; phosphorylated form is trapped, reflecting glucose metabolism in cells.

Perfusion defect with preserved ventilation

A V/Q mismatch pattern suggesting pulmonary embolism; a matched defect instead suggests parenchymal lung disease such as COPD or pneumonia.

Bone scan superscan

Diffuse increased skeletal uptake with faint renal and soft-tissue uptake, reflecting widespread bone metastases or metabolic bone disease.

Tc-99m MAG3 vs DTPA

MAG3 is secreted by renal tubules and preferred for assessing renal function or transplant; DTPA is filtered by glomeruli and used for GFR measurement.

I-123 versus I-131

I-123 is a pure gamma emitter used for imaging and uptake studies; I-131 emits beta particles plus gamma and is used for therapy.

Hepatobiliary scan in cholecystitis

Nonvisualization of the gallbladder at 60 minutes with normal hepatic uptake suggests acute cholecystitis; used also for biliary leak and obstruction.

Renal captopril renography

Scan performed after ACE inhibitor administration to detect renovascular hypertension; affected kidney shows delayed uptake or altered renogram curve.

Radiation dose MIRD schema

Dose equals S-value times cumulated activity; accounts for administered activity, residence time, and energy deposited per decay in a target organ.

Stable iodine blocking

Administering nonradioactive iodine before I-131 blocks thyroid uptake, reducing thyroid dose in accidental exposure or therapeutic settings.

Sentinel lymph node mapping

Injection of radiotracer near a tumor with intraoperative gamma probe detection identifies the first draining lymph node for biopsy.

Time-of-flight PET

Uses timing differences of detected annihilation photons to localize events along the line of response, improving image quality and lesion detection.

Four osteopathic tenets

Body is a unit; structure and function are reciprocally interrelated; body is self-regulating and self-healing; treatment is based on these principles.

Somatic dysfunction definition

Impaired or altered function of related somatic components (skeletal, arthrodial, myofascial) and related vascular, lymphatic, and neural elements.

TART mnemonic

Criteria for somatic dysfunction: Tissue texture changes, Asymmetry, Restriction of motion, and Tenderness on examination of the affected region.

Viscerosomatic reflex

Visceral afferents converging on the same spinal levels as somatic afferents produce segmental tissue texture change, tenderness, and restricted motion.

Sympathetic nervous system levels

Sympathetic outflow arises from T1 through L2; parasympathetic outflow arises via cranial nerves III, VII, IX, X and sacral segments S2–S4.

Chapman points

Anterior and posterior reflex points associated with visceral or lymphatic dysfunction, used diagnostically and therapeutically in osteopathic practice.

Thoracic inlet lymphatic release

Osteopathic technique releasing fascial restriction at the thoracic inlet to improve lymphatic and venous return from the head, neck, and upper extremities.

Abdominal diaphragm release

Technique addressing diaphragmatic restriction to improve lymphatic flow and venous return from abdominal and pelvic viscera.

Contraindications to OMT

Acute fracture, dislocation, severe osteoporosis, bone malignancy or metastases, joint instability, and acute regional infection warrant avoidance or modification of treatment.

Myofascial release principle

Sustained light force applied to restricted fascia allows tissue to release and lengthen, restoring motion and reducing associated tenderness.

Muscle energy technique

Patient performs isometric or isotonic contraction against operator resistance at a barrier, followed by relaxation and repositioning to improve motion.

High-velocity low-amplitude technique

Rapid, short-amplitude thrust applied at a motion barrier to restore motion; requires careful screening for contraindications such as instability or fracture.

Strain-counterstrain technique

Positioning the body in the position of maximal comfort for a tender point for a set time, followed by slow return, reducing tenderness and dysfunction.

Osteopathic structural exam

Systematic assessment of posture, symmetry, tissue texture, tenderness, and motion to identify somatic dysfunction before and after treatment.

Lymphatic pump technique

Rhythmic compression and release of the thorax or extremities to promote lymphatic and venous return; used for edema and lymphatic congestion.

Sacroiliac somatic dysfunction

Restricted or asymmetric sacral motion with tenderness; managed with muscle energy, counterstrain, or other osteopathic techniques after screening for red flags.

Cranial rhythmic impulse

Palpable rhythmic motion assessed in cranial osteopathy; used as a diagnostic and treatment guide within osteopathic manipulative practice.