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Radiation-induced valvular heart disease
Radiation-induced valvular heart disease is calcification and dysfunction of heart valves, usually aortic and mitral, caused by chest radiation therapy, appearing a median 23 years later.
Radical cystoprostatectomy
Radical cystoprostatectomy is an operation removing the bladder and prostate together with the seminal vesicles, vas deferens, and pelvic lymph nodes, performed to treat bladder cancer.
Radical hysterectomy
Radical hysterectomy is a surgical operation that removes the uterus, parametrium, and upper one-third to one-half of the vagina, usually with pelvic lymph node dissection, to treat early-stage cervical cancer.
Radical mastectomy
The radical (Halsted) mastectomy is an operation for breast cancer removing the breast, both pectoral muscles, and all axillary lymph nodes, devised by William Halsted in 1894.
Radical neck dissection
Radical neck dissection is an operation for head and neck cancer removing neck lymph nodes plus the internal jugular vein, sternocleidomastoid muscle, and spinal accessory nerve.
Radical nephrectomy
Radical nephrectomy is a urologic operation that removes an entire kidney, with its surrounding fat within Gerota's fascia, to treat renal cell carcinoma, reserved for larger or more complex tumors.
Radical prostatectomy
Radical prostatectomy, also called open radical prostatectomy, is an operation that removes the prostate gland and seminal vesicles to cure prostate cancer confined to the gland, now mostly robot-assisted.
Radical resection
Radical resection is the en bloc surgical removal of a malignant tumor with a margin of healthy tissue and often regional lymph nodes, aiming to leave no cancer cells behind.
Radical retropubic prostatectomy
Radical retropubic prostatectomy: open removal of the prostate, seminal vesicles, and surrounding tissue through a lower abdominal incision; refined by Walsh's 1982 nerve-sparing anatomic technique, now compared with robotic surgery.
Radical trachelectomy
Radical trachelectomy is a fertility-sparing operation for early-stage cervical cancer that removes the cervix, upper vagina, and parametria while preserving the uterus for future pregnancy.
Radicular cyst
Radicular cyst (periapical, apical cyst): inflammatory odontogenic cyst on a non-vital tooth, arising from periapical granuloma via epithelial rests of Malassez; diagnosed by histopathology, treated by enucleation or marsupialization.
Radiculopathy
Radiculopathy, also called radiculitis or nerve root disorder, is pain, numbness, tingling, and weakness from a compressed spinal nerve root; types are cervical, thoracic, and lumbar, most often caused by disc herniation.
Radioactive iodine therapy
Radioactive iodine therapy is a nuclear medicine treatment in which radioactive iodine-131 is taken by mouth to destroy thyroid tissue, treating hyperthyroidism and differentiated thyroid cancer.
Radioallergosorbent Test
Radioallergosorbent test (RAST): the first blood assay for allergen-specific IgE, introduced by Wide, Bennich, and Johansson in 1967 and commercialized as Phadebas RAST in 1974; now replaced by fluorescence enzyme assays but still a colloquial term.
Radiochemotherapy
Radiochemotherapy (chemoradiotherapy, CRT) is the combination of chemotherapy with radiotherapy, given concurrently or sequentially, and standard of care in cervical, rectal, anal, and nasopharyngeal cancer.
Radiocontrast agent
Radiocontrast agent (contrast medium): iodinated compounds for X-ray/CT, gadolinium chelates for MRI, barium sulfate for GI imaging, and microbubbles for ultrasound; classes differ in osmolality, safety, and kidney and thyroid risks.
Radiodynamic therapy
Radiodynamic therapy is a cancer treatment in which X-rays activate a sensitizing agent that generates reactive oxygen species to kill tumor cells, reaching deep tumors that visible or near-infrared light cannot.
Radioembolization
Therapeutic radioembolization (SIRT, TARE, Y-90 radioembolization): catheter-based liver cancer therapy injecting yttrium-90 glass or resin microspheres into hepatic arteries; used for unresectable HCC and metastases, with FDA-approved TheraSphere and SIR-Spheres devices.
Radiofrequency ablation
Radiofrequency ablation (RFA): catheter-based cardiac procedure using RF-heated tips to destroy arrhythmic tissue; standard for AF pulmonary vein isolation since Haissaguerre's 1998 work, with ~4.5% major complication rate.
Radiofrequency neurotomy
Radiofrequency neurotomy is a pain procedure that heats small spinal nerves, such as the facet joint's medial branch nerves, to interrupt chronic back or neck pain for months.
Radiofrequency Therapy
Radiofrequency therapy is the use of radio waves to heat, stimulate, or ablate tissue, encompassing radiofrequency ablation, pulsed radiofrequency, and non-invasive techniques used for pain, arrhythmias, and tumors.
Radiofrequency thermocoagulation
Radiofrequency thermocoagulation is a minimally invasive pain procedure that heats and destroys nerve tissue with an electrode, most often for trigeminal neuralgia and facet joint pain.
Radiographer
Radiographer (radiologic technologist): allied health professional producing diagnostic images (X-ray, CT, MRI, PET) or delivering radiotherapy. Distinct from the radiologist, a physician who interprets images; UK titles protected by HCPC registration.
Radiographic Image Enhancement
Radiographic image enhancement is the digital processing of X-ray and other radiation images after acquisition, adjusting contrast and frequency properties so clinically important features stand out.
Radiographic Magnification
Radiographic magnification: enlargement of an X-ray image, factor M = SID/SOD. Used in magnification mammography for microcalcifications; geometric magnification outperforms electronic zoom; must be corrected in hip templating.
Radiographics : a review publication of the Radiological Society of North America, Inc
RadioGraphics (ISSN 0271-5333 print, 1527-1323 online) is RSNA's peer-reviewed education journal in diagnostic radiology, launched 1981, edited by Christine Cooky Menias, publishing solicited RSNA meeting exhibits; 2025 impact factor 6.2.
Radiography
Radiography (projection X-ray imaging) records a static image after an X-ray beam passes through the body, distinct from fluoroscopy and CT. Discovered via Röntgen's 1895 X-rays; lower dose than CT; now digital and AI-assisted.
Radioguided surgery
Radioguided surgery is a technique in which a radioactive tracer, detected with a handheld gamma probe, guides surgeons in removing tissue, notably for sentinel lymph node biopsy.
Radioimmunodetection
Radioimmunodetection (RAID), also called radioimmunoscintigraphy, is a nuclear medicine technique using radiolabeled monoclonal antibodies to image tumors; it evolved into immunoPET after FDG-PET displaced it for staging.
Radioimmunoprecipitation Assay
Radioimmunoprecipitation assay (RIPA, Farr assay): sensitive immunoassay using radiolabeled antigens to detect and quantify specific antibodies in serum or CSF; gold standard for AChR antibodies in myasthenia gravis, limited by radioisotope handling.