All articles starting with R
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Renaissance robotic guidance system
The Renaissance robotic guidance system is a bone-mounted miniature surgical robot by Mazor Robotics of Israel, released in 2011 to guide pedicle screws during spinal surgery.
Renaissance Technologies
Renaissance Technologies, also known as RenTech, is an American quantitative hedge fund firm founded by mathematician Jim Simons in 1982, based in East Setauket, New York.
Renaissance theatre
Renaissance theater is the theater of Renaissance Europe, driven by Italy's rediscovery of Vitruvius and perspective scenery, with England evolving a commercial Elizabethan drama from medieval mystery plays.
Renaissance World Tour
Renaissance World Tour (Renaissance Tour), Beyoncé's ninth concert tour supporting her 2022 album Renaissance; 56 stadium shows, May 10 to October 1, 2023, Stockholm to Kansas City; grossed $579.8 million from 2.78 million attendees.
Renaixença
Renaixença, Catalan for "rebirth," is the nineteenth-century movement that revived the Catalan language for literary use, starting with Aribau's 1833 poem Oda a la Pàtria.
Renal agenesis
Renal agenesis: congenital complete absence of one (unilateral, about 1 in 2,000 births) or both (bilateral, about 1 in 8,500) kidneys, caused by failed ureteric bud-metanephric mesenchyme induction, GDNF-RET pathway genes; bilateral forms cause fatal Potter syndrome.
Renal angioplasty
Renal angioplasty is a catheter-based procedure that widens a narrowed renal artery with balloon dilation and often a stent, used for renovascular hypertension and ischemic nephropathy.
Renal arteriovenous malformation
Renal arteriovenous malformation (rAVM, kidney AVM) is a rare abnormal artery-vein communication in the kidney, congenital in about 25% of cases, presenting mainly with hematuria and treated chiefly by transcatheter embolization.
Renal artery
Renal artery: paired artery from the abdominal aorta (L1-L2 level) supplying each kidney; divides into anterior/posterior divisions; accessory renal arteries occur in about 21% of people; main disease is renal artery stenosis causing renovascular hypertension.
Renal artery stenosis
Renal artery stenosis (RAS), also called atherosclerotic renovascular disease, is narrowing of one or both renal arteries, about 90% from atherosclerosis and most of the rest from fibromuscular dysplasia, causing renovascular hypertension and ischemic nephropathy; trials (ASTRAL, CORAL) show stenting adds no benefit over medical therapy for most patients.
Renal biopsy
Renal biopsy, also called kidney biopsy, is a diagnostic procedure in which a needle removes a small sample of kidney tissue, examined under a microscope to diagnose kidney disease.
Renal cell carcinoma
Renal cell carcinoma (RCC), also called hypernephroma or renal adenocarcinoma, is the most common adult kidney cancer, arising from renal tubule lining; classified by WHO 2022 into six categories, driven by VHL inactivation, treated by surgery and immunotherapy.
Renal Circulation
Renal circulation: blood flow through the kidney's vessels, about 20% of cardiac output (~1 L/min), with glomerular and peritubular capillaries in series and myogenic plus tubuloglomerular feedback autoregulation.
Renal colic
Renal colic, also called ureteric colic, is severe loin pain from acute ureteral obstruction by a stone; lifetime risk 12% men, 6% women; NSAIDs first-line, low-dose non-contrast CT key imaging.
Renal coloboma syndrome
Renal coloboma syndrome, also called papillorenal syndrome or PAX2-related disorder, is an autosomal dominant condition caused by PAX2 variants, combining renal hypodysplasia (92% of cases) with optic nerve dysplasia or coloboma (77%), often progressing to kidney failure.
Renal dysplasia
Renal dysplasia (kidney dysplasia), a CAKUT malformation with disorganized kidney tissue, primitive ducts, and cartilage; leading cause of pediatric kidney failure, diagnosed by ultrasound, managed supportively.
Renal glycosuria
Renal glycosuria (renal glucosuria), also familial renal glycosuria, is benign glucose in urine with normal blood sugar, caused by SLC5A2/SGLT2 mutations or acquired tubular defects, distinct from diabetic glycosuria.
Renal hypoplasia
Renal hypoplasia (ORPHA:93101, ICD-10 Q60.3-Q60.5) is a congenital malformation of abnormally small kidneys with normal corticomedullary differentiation and reduced nephron number, caused by developmental gene mutations (HNF1B, PAX2, PBX1) or environmental factors, risking hypertension and chronic kidney disease.
Renal intercalated cell
Renal intercalated cell (intercalated cell, IC): minority epithelial cell of the kidney connecting tubule and collecting duct, in type A, type B, and non-A non-B subtypes, mediating acid, bicarbonate, chloride, and sodium transport and blood pressure regulation.
Renal mass biopsy
Renal mass biopsy (RMB) is a percutaneous needle procedure that samples a kidney tumor to determine whether it is benign or malignant, and to identify its subtype and grade.
Renal medullary carcinoma
Renal medullary carcinoma (RMC), SMARCB1-deficient renal medullary carcinoma, is a rare aggressive kidney cancer of the renal medulla in young people with sickle cell trait; 98% present metastatic, median survival 9 to 13 months.
Renal parenchymal hypertension
Renal parenchymal hypertension is high blood pressure caused by disease of the kidney tissue itself, which retains sodium and water; it accounts for 3% to 5% of hypertension.
Renal physiology
Renal physiology: how the kidneys filter blood, reabsorb and secrete solutes, and regulate homeostasis. Key facts: normal GFR 100-125 mL/min/1.73 m², myogenic and tubuloglomerular autoregulation, countercurrent multiplication, renal functional reserve.
Renal replacement therapy
Renal replacement therapy (RRT, kidney replacement therapy) covers hemodialysis, peritoneal dialysis, and kidney transplant for severe acute kidney injury or stage 5 CKD, with conservative management as a non-dialysis option; dialysis typically starts at eGFR 5-7 ml/min/1.73 m2 or on emergency indications.
Renal scintigraphy
Renal scintigraphy is a nuclear medicine imaging method that injects a radioactive tracer, records its passage through the kidneys with a gamma camera, and measures perfusion, function, and drainage.
Renal sympathetic denervation
Renal sympathetic denervation (renal denervation, RDN) is a catheter-based procedure ablating renal sympathetic nerves with radiofrequency, ultrasound, or alcohol energy to lower uncontrolled blood pressure; FDA approved Recor Paradise and Medtronic Symplicity Spyral systems in November 2023.
Renal tubular acidosis
Renal tubular acidosis (RTA), including distal (type 1), proximal (type 2), and hyperkalemic (type 4) forms, is a group of tubular kidney disorders causing normal-anion-gap metabolic acidosis, diagnosed by urine pH and provocative tests and treated with alkali therapy.
Renal tubular dysgenesis
Renal tubular dysgenesis (RTD), or primitive renal tubule syndrome, is a severe fetal kidney disorder with absent proximal tubules, causing anuria, oligohydramnios, Potter sequence, and usually perinatal death; genetic forms are autosomal recessive in ACE, AGT, AGTR1, or REN.
Renal urea handling
Renal urea handling: how the kidney filters, reabsorbs, secretes, and recycles urea via UT-A1/UT-A3, UT-A2, and UT-B transporters, regulated by vasopressin, to build the inner medullary osmotic gradient for concentrated urine.
Renal vein
The renal vein, known in Latin as vena renalis, drains each kidney into the inferior vena cava; the left vein is much longer than the right.