Medical abbreviations and acronyms (C)

This article contains a list of commonly used medical abbreviations and acronyms that start with the letter C and may be encountered in medicine and radiology (please keep both the main list and any sublists in alphabetic order).

A - B - C - D - E - F - G - H - I - J - K - L -M - N - O - P - Q - R - S - T - U - V - W - X - Y - Z - misc

• C
  • caesarean (C-section)
  • carbon
  • Celsius/centigrade
  • cervical
  • coulomb (SI unit of charge)
  • cysteine (single letter amino acid code)
  • cytosine (DNA nucleotide)
  • hundred (Roman numeral)
• c: speed of light in a vacuum (always lowercase)
• C1-C3: cruciate pulleys
• C1-C7
  • cervical spinal nerve roots
  • cervical vertebrae
• C2H5OH: ethanol
• C8: eighth cervical nerve root
• CA
  • calcification
  • cancer
  • carcinoma
  • coronary angiography
• Ca: calcium
• CA 15-3: carcinoma antigen 15-3
• CA 19-9: cancer antigen 19-9
• CA 27-29: cancer antigen 27-29
• CA-125: cancer antigen 125
• CAA: coronary artery aneurysm
• CABG: coronary artery bypass graft
• CAC: coronary artery calcification
• CACG: chronic angle-closure glaucoma
• CAD
  • computer-aided diagnosis
  • coronary artery disease
• CADASIL: cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy
• CAE: coronary artery ectasia
• CAG: coronary artery graft
• CAGS: coronary artery graft surgery
• CAH: congenital adrenal hyperplasia
• CAI: chronic ankle instability
• CAIPIRINHA: controlled aliasing in parallel imaging results in higher acceleration (Siemens)
• CAK: cumulative air kerma
• CAM: comprehensive arthroscopic management
• CANVAS: cerebellar ataxia with neuropathy and vestibular areflexia syndrome
• CAP
  • chest-abdomen-pelvis (as in CT scan of CAP)
  • community-acquired pneumonia
• CAPD: continuous ambulatory peritoneal dialysis
• CARASIL: cerebral autosomal recessive arteriopathy with subcortical infarcts and leukoencephalopathy
• CAS: carotid artery stenosis
• CASA: computer-assisted semen analysis
• CASH: chemotherapy-associated steatohepatitis
• CAT
  • computed axial tomography or computer-aided tomography
  • critically-appraised topic
• c/b: complicated by
• CB: ciliary body
• CBAVD: congenital bilateral absence of vas deferens
• CBC: complete blood count
• CBCT: cone beam CT
• CBD: common bile duct
• CBF: cerebral blood flow
• CBH: change in bowel habit
• CBI: continuous bladder irrigation
• CBV: cerebral blood volume
• cc: with correction (ophthalmology)
• CC
  • caudocranial or caudocraniad
  • chief complaint
  • copy to (letters/email)
  • corpus callosum
  • craniocaudad or craniocaudal
  • Creative Commons
  • cubic centimetre (cm³ preferred)
• CCA: common carotid artery
• CCAM: congenital cystic adenomatoid malformation
• CCC: continuous curvilinear capsulorrhexis
• CCCT: clomiphene citrate (Clomid) challenge test
• CCD
  • caput-collum-diaphyseal (angle)
  • charge-coupled device
  • crossed cerebellar diaschisis
• CCF
  • caroticocavernous fistula
  • congestive cardiac failure
• CCL: corpus callosum lipoma
• CCP:
  • central chest pain
  • cyclic citrullinated peptide (antibody, in rheumatoid arthritis)
• CCS
  • chronic coronary syndrome
  • combined conduit score
  • clear cell sarcoma
• CCST: Certificate of Completion of Specialist Training (UK)
• CCT: Certificate of Completion of Training (UK)
• CCU
  • coronary care unit
  • critical care unit
• CD
  • clinical director
  • Clostridioides difficile
  • cluster of differentiation (immunology, e.g. CD4, CD8, etc.)
  • common duct
  • compact disc
  • Cotrel-Dubousset
  • Crohn disease
  • cystic duct
• Cd: cadmium
• cd: candela (SI unit of luminous intensity)
• CDC: Centres for Disease Control and Prevention (US federal agency)
• CDE: complete dental evaluation
• CDH
  • congenital diaphragmatic hernia
  • congenital dislocation of the hip
• C.diff: Clostridioides difficile
• CDI: ColorColour Doppler imaging
• CDR: clinical decision rules
• CD-ROM: compact disc - read only memory disc
• CDS
  • carotid duplex study
  • clinical decision support
• CDT
  • catheter-directed therapy
  • catheter-directed thrombolysis
  • Clostridioides difficile  toxin 
• CE
  • cataract extraction
  • contrast-enhanced
• Ce: cerium
• CEA
  • carcinoembryonic antigen
  • carotid endarterectomy
• CECT: contrast-enhanced computed tomography
• CEMR: contrast-enhanced magnetic resonance
• CEMRI: contrast-enhanced magnetic resonance imaging
• CERAB: covered endovascular reconstruction of the aortic bifurcation
• CES: cauda equina syndrome
• CESM: contrast-enhanced spectral mammography
• CEUS: contrast-enhanced ultrasound
• CF: cystic fibrosis
• cf: compare with (Latin: confer)
• CFA: common femoral artery
• CFC: cardiofaciocutaneous syndrome
• CFDM: cystic fibrosis - related diabetes mellitus
• CFL: calcaneofibular ligament
• CFR: case fatality rate
• CFS: chronic fatigue syndrome
• CFTS: combined first trimester screening
• CFV: common femoral vein (strictly does not exist)
• cgs: centimetre-gram-second (superseded system of units)
• Ch: Charrière (unit)
• CHALICE: children’s head injury algorithm for prediction of clinically important event
• CHANTER: cerebellar, hippocampal, and basal nuclei transient oedema with restricted diffusion syndrome
• CHAOS: congenital high airway obstruction syndrome
• CHB: complete heart block
• CHD
  • common hepatic duct
  • congenital heart disease
  • coronary heart disease
• chem: chemistry
• CHESS: chemical shift selective pulses (all vendors)
• CHF: congestive heart failure
• CHILD syndrome: congenital hemidysplasia with ichthyosiform erythroderma and limb defects
• CHL
  • conductive hearing loss
  • coracoacromial ligament
• CHO: carbohydrate
• Chol: cholesterol
• CHOP: cyclophosphamide, doxorubicin (hydroxydaunomycin), Oncovin^® (vincristine), prednisolone
• CI
  • compound imaging
  • confidence interval
  • contraindication
  • cardiac index
• Ci: curie (non-SI unit of radioactivity)
• C/I: contraindication
• CIA: common iliac artery
• CID: concealed interstitial delamination
• CIDP: chronic inflammatory demyelinating polyneuropathy
• CIED: cardiac implantable electronic device
• CIN
  • cervical intraepithelial neoplasia
  • contrast-induced nephropathy
  • contrast-induced neurotoxicity
• CIRS: chronic inflammatory response syndrome
• CIRSE: Cardiovascular and Interventional Radiology Society of Europe
• CIS: clinically isolated syndrome
• CISS: constructive interference in steady state (Siemens)
• CIV: common iliac vein
• CJD: Creutzfeldt-Jakob disease
• CK: creatine kinase
• CKD: chronic kidney disease
• Cl: chlorine
• CLABSI: central line-associated bloodstream infection
• CLD:
  • chronic liver disease
  • chronic lung disease (of infancy)
  • congenital lactase deficiency
  • congenital limb deficiency
  • cystic lung disease
• CLEAR: constant level appearance
• CLIPPERS: chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids
• cm: centimetre
• CMCJ: carpometacarpal joint
• CMD: coronary microvascular dysfunction
• CME
  • continuing medical education
  • cystoid macular oedema
• CMF: chondromyxoid fibroma
• CMP: cardiomyopathy
• CMR: complete metabolic response
• CMT
  • Charcot-Marie-Tooth disease
  • coeliacomesenteric trunk
• CMV: cytomegalovirus
• CN: cranial nerve
• CNA: chronic necrotising aspergillosis
• CNLD: chronic neonatal lung disease
• CNN: convolutional neural network
• CNR: contrast-to-noise ratio
• CNS: central nervous system
• CNV: choroidal neovascularizationneovascularisation
• CNVM: choroidal neovascular membrane
• CO
  • carbon monoxide
  • cardiac output
• Co
  • cobalt
  • coccygeal vertebrae (Co1, Co2, etc)
• C/O: complaining of
• CoA: coarctation of aorta
• COAD: chronic obstructive airways disease
• COAG: chronic open-angle glaucoma
• COBH: change of bowel habit
• COCP: combined oral contraceptive pill
• COH: controlled ovarian hyperstimulation
• COHb: carboxyhemoglobincarboxyhaemoglobin
• COLD: Cowden-Lhermitte-Duclos syndrome
• COM: chronic otomastoiditis
• COMARE: Committee on Medical Aspects of Radiation in the Environment (UK)
• COP
  • combined oral contraceptive pill
  • cryptogenic organising pneumonia
• COPD: chronic obstructive pulmonary disease
• Cor: coronal
• CoR: College of Radiographers (UK)
• COVID-19: CoronaVirus Disease-2019
• CoV: coronavirus
• COW: circle of Willis
• CP
  • caeruloplasmin
  • cerebral palsy
  • cervical position
  • chest pain
  • cross-polarisation
• CPA
  • cerebellopontine angle
  • costophrenic angle
• CPAM: congenital pulmonary airway malformation
• CPAP: continuous positive airway pressure
• CPB: cardiopulmonary bypass
• CPC
  • choroid plexus cyst
  • cyclophotocoagulation
• CPD: continuing professional development
• CPE: carbapenem-producing enterobacteriaceae
• CPFE: combined pulmonary fibrosis and emphysema
• CPFI: chest pain for investigation
• CPK: creatine phosphokinase
• CPR
  • cardiopulmonary resuscitation
  • curved planar reformation
• CPS: complex partial seizure
• CQC: Care Quality Commission (UK)
• CR: complete response (RECIST)
• Cr
  • chromium
  • creatinine
• CRA: coral reef aorta
• CRAB: carbapenem-resistant Acinetobacter baumannii
• CRAO: central retinal artery occlusion
• CRC: colorectal cancer or colorectal carcinoma
• CRE: carbapenem-resistant enterobacteriaceae
• Creat: creatinine
• CREST: calcinosis, Raynaud phenomenon, oesophageal dysmotility, sclerodactyly, telangiectasia
• CRF
  • chronic renal failure
  • corticotropin-releasing factor
• CRIF: closed reduction internal fixation
• CRION: chronic relapsing inflammatory optic neuropathy
• CRISPR: clustered regularly interspaced short palindromic repeats
• CRL: crown-rump length
• CRM: circumferential resection margin
• CRMD: cardiac rhythm management device
• CRP: C-reactive protein
• CRPC: castrate resistant prostate cancer
• CRPS: complex regional pain syndrome
• CRS: chronic rhinosinusitis
• CRT
  • capillary refill time
  • cathode ray tube
• CRT-D: cardiac resynchronisation therapy device  
• CRT-P: cardiac resynchronisation therapy pacemaker
• CRTX: chemoradiotherapy
• CRUK: Cancer Research UK (charity)
• CRVO: central retinal vein occlusion
• Cryo: cryotherapy
• CS
  • Caesarean section
  • cavernous sinus
  • chemical shift
  • compressed sensing (MRI)
  • coronary sinus
  • corticospinal
• Cs: caesium
• C&S: culture and sensitivity
• C/S: caesarean section
• CSCR: central serous chorioretinopathy
• CSD: cortical spreading depression 
• cSDH: chronic subdural haemorrhage
• CSF: cerebrospinal fluid
• CS-MRI: chemical shift MRI
• CSNT: calves soft and non tender
• CSOM: chronic serous otitis media
• CSR: central serous retinopathy
• CSS: Churg-Strauss syndrome
• CST: cervical screening test
• CSU: catheter specimen of urine
• CSW: commercial sex worker
• CT
  • chemotherapy
  • computed tomography
• CTA: computed tomography angiogram or aortogram
• CTAP: computed tomography of abdomen and pelvis
• CTAVN: cystic tumour of the atrioventricular node
• CTB: computed tomography of the brain
• CTC: computed tomography colonography / colonoscopy
• CTCA
  • computed tomography of chest and abdomen
  • computed tomography coronary angiogram
• CTCAP: computed tomography of chest, abdomen and pelvis
• CTEV: congenital talipes equinovarus
• CTD: connective tissue disease
• CTDI: CT dose index
• ctDNA: circulating-tumor-tumour DNA
• CTED: chronic thromboembolic disease
• CTEPH: chronic thromboembolic pulmonary hypertension
• CTEV: congenital talipes equinovarus
• CTG
  • cardiotocography
  • caudothalamic groove
• CTH: computed tomography head
• CTIVC: computed tomography intravenous cholangiogram
• CTIVP: computed tomography intravenous pyelogram
• CTO: chronic total occlusion
• CTP: computed tomography perfusion
• CTPA: computed tomography pulmonary angiogram/angiography
• CTPE: computed tomography pulmonary embolus study
• CTR: cardiothoracic ratio
• CTS: carpal tunnel syndrome
• CTSI: CT severity index 
• CTTAP: computed tomography of the thorax, abdomen and pelvis
• CTU: computed tomography urogram
• CTV
  • clinical target volume
  • computed tomography venogram
• CTX: chemotherapy
• CTZ: chemosensitive trigger zone  
• Cu: copper (Latin: cuprum)
• CUP: cancer of unknown primary (or carcinoma of unknown primary)
• CUS: cranial ultrasound
• CV: curriculum vitae
• CVA: cerebrovascular accident (the term stroke is preferred)
• CVAD: central venous access device
• CVC: central venous catheter
• CVE: cerebrovascular event (the term stroke is preferred)
• cVEMP: cervical vestibular-evoked myogenic potentials
• CVID: common variable immune deficiency
• CVL: central venous line
• CVP: central venous pressure
• CVS
  • cardiovascular system
  • chorionic villus sampling
• CWD: continuous wave Doppler
• CWP: coal workers' pneumoconiosis
• Cx
  • cervix
  • circumflex artery
  • coccygeal vertebra (Cx1, Cx2, etc.)
  • complication
• CXR: chest x-ray
• Cys: cysteine
• CZ: central zone (prostate)