Human health and medicine

Impaired fasting glucose

Impaired fasting glucose (IFG), impaired fasting glycaemia, is prediabetes defined by fasting plasma glucose of 100–125 mg/dL (ADA) or 6.1–6.9 mmol/L (WHO), introduced in 1997, driven by hepatic insulin resistance.

Impaired glucose tolerance

Impaired glucose tolerance (IGT), a prediabetes state defined by 2-hour plasma glucose 140–199 mg/dL on a 75-g OGTT; risk factor for type 2 diabetes and cardiovascular disease; preventable by lifestyle intervention or metformin.

Impairment of colour vision

Impairment of color vision, commonly called color blindness or color vision deficiency, is a reduced ability to distinguish colors, affecting about 8% of males and often inherited.

Impairment of visual field

Impairment of visual field (ICD-11 9D41) is partial or total loss of the area seen with fixed gaze, caused by glaucoma, stroke, retinal disease; measured by perimetry, affecting driving and mobility.

Impedance cardiography

Impedance cardiography, also called thoracic electrical bioimpedance, is a noninvasive method that estimates stroke volume, cardiac output, and related hemodynamic parameters from changes in the electrical impedance of the chest.

Impedance manometry

Impedance manometry is a diagnostic technique that combines manometry with electrical impedance on a single catheter. It is used to evaluate dysphagia and reflux disease.

Impedance myography

Impedance myography, also known as electrical impedance myography, is a noninvasive technique that passes a small electrical current through muscle to assess neuromuscular disease severity.

Impedance planimetry

Impedance planimetry is a diagnostic technique measuring cross-sectional area and pressure inside a hollow GI lumen to assess wall distensibility, best known through the EndoFLIP system used during endoscopy and foregut surgery.

Impedance Plethysmography

Impedance plethysmography, also known as rheography or impedance phlebography, is a noninvasive technique that measures blood volume changes through electrical impedance between electrodes on the skin.

Impella

Impella: Abiomed's catheter-mounted microaxial heart pump, first used 1999 in Belgium, over 330,000 patients treated; unloads the left ventricle for high-risk PCI and cardiogenic shock, distinct from balloon pumps and ECMO.

Imperforate hymen

Imperforate hymen, a congenital obstruction of the vaginal opening by hymenal tissue, incidence about 0.05–0.1%; presents after menarche with amenorrhea, cyclic pain, hematocolpos; treated by hymenotomy or hymenectomy.

Impetigo

Impetigo (pyoderma) is a contagious superficial bacterial skin infection caused by Staphylococcus aureus, Streptococcus pyogenes, or both, occurring mainly in children aged 2 to 5, with honey-crusted lesions treated by topical or oral antibiotics.

Implant-based breast reconstruction

Implant-based breast reconstruction, also called implant breast reconstruction, is surgery that rebuilds the breast after mastectomy with a silicone or saline implant, placed directly or after staged tissue expansion.

Implant-Supported Dental Prosthesis

An implant-supported dental prosthesis is a replacement tooth, bridge, or denture supported by titanium implants anchored in the jawbone through osseointegration rather than by natural teeth.

Implantable cardioverter-defibrillator

Implantable cardioverter-defibrillator (ICD): battery-powered implanted device invented by Mirowski and Mower that detects ventricular tachycardia or fibrillation and delivers pacing or shocks; first implanted 1980, FDA-approved 1985, shown to cut mortality in MADIT and MADIT II.

Implantable cardioverter-defibrillator implantation

Implantable cardioverter-defibrillator (ICD) implantation is the surgical placement of a device that detects ventricular tachycardia or fibrillation and terminates them with pacing or shocks, preventing sudden cardiac death.

Implantable collamer lens implantation

Implantable collamer lens (ICL) implantation is a refractive surgery procedure that corrects myopia by placing a phakic intraocular lens between the iris and the natural lens.

Implantable Infusion Pumps

Implantable infusion pumps (implantable intrathecal drug delivery systems): surgically implanted, self-powered pumps delivering chemotherapy or analgesics at controlled rates; first morphine pump 1981, SynchroMed II most used, ~1% flow error, 5.9-year battery life.

Implantable Neurostimulators

Implantable neurostimulators are surgically placed devices that deliver electric stimulation to nerves, the spinal cord, or the brain, used for epilepsy, Parkinson's disease, and chronic pain.

Implanted Electrodes

Implanted electrodes are surgically placed conductors that record from or stimulate nerves, brain, or muscle, powering cochlear implants, pacemakers, DBS, and brain-computer interfaces; key issues are electrode-tissue interface impedance, biocompatibility, and long-term reliability.

Implantoplasty

Implantoplasty is a dental procedure in which the exposed threads of a titanium implant are removed and polished smooth to retain less plaque during surgical treatment of peri-implantitis.

Impossible color

Impossible colors are color percepts, such as reddish green or the laboratory color olo, that no light spectrum can produce; they arise from opponent-process color coding or direct cone stimulation.

Impression cytology

Impression cytology is a minimally invasive ophthalmology technique, introduced in 1977, that presses a filter membrane against the eye to collect superficial epithelial cells for cytological, immunological, or molecular examination.

Imprinting errors

Imprinting errors: genetic or epigenetic disruptions of genomic imprinting, the parent-of-origin silencing of about 1% of human genes, causing disorders such as Prader-Willi, Angelman, Beckwith-Wiedemann, and Silver-Russell syndromes, detectable by methylation assays rather than sequencing.

Impulse oscillometry

Impulse oscillometry (IOS) is a lung function test that measures respiratory resistance and reactance during tidal breathing, useful for young children and patients who cannot perform spirometry.

Imrecoxib

Imrecoxib (艾瑞昔布, brand Hengyang) is a Chinese-developed selective COX-2 inhibitor for osteoarthritis pain, codeveloped by Guo Zongru's IMM group with Hengrui and SFDA-approved in 2011 as a class 1.1 drug.

Imsidolimab

Imsidolimab (ANB019) is a humanized IgG4 monoclonal antibody antagonist of the interleukin-36 receptor developed by AnaptysBio and licensed to Vanda Pharmaceuticals, tested in phase 2 GALLOP and phase 3 GEMINI-1/2 trials for generalized pustular psoriasis, with a US BLA under review.

Oct 20, 2026

IMSIII trial

IMSIII (Interventional Management of Stroke III, NCT00359424) was a phase 3 randomized trial of endovascular therapy plus IV t-PA versus IV t-PA alone in acute ischemic stroke; stopped for futility at 656 patients, it showed no 90-day outcome benefit (40.8% vs 38.7% mRS 0-2).

In situ simulation

In situ simulation is a healthcare training method that runs realistic clinical scenarios in the actual patient care environment with on-shift staff, exposing latent safety threats before they harm a patient.