CT Protocols


Q: Why does it makes sense to protocol cases as we receive the orders (as opposed to the day the case is scheduled)?

A: There is more opportunity to clarify issues with the clinician. e.g. if a clinic orders a case, you want to clairfy things while the ordering person is still in clinic. If an MR has be be changed from C- to C-/C+, we may have to redo the preauthorization to get proper reimbursement. If the patient arrives for an appointment and is sent home because the preauthorization is incorrect, how would you think they feel?


  • Mount Sinai BISLR Body CT Protocols
  • Radiation Risk Calculator
  • Radiation safety information for patients
    • Annual background radiation ~3.1 mSv/year
    • CXR (PA&Lat) ~0.1 mSv
    • 7 hour airline flight ~0.02 mSv
  • Gurney Weight Limit ~ 350 pounds
  • If the patient has a severe anaphylactic reaction but needs CO+, can use BariCat instead of Omnipaque


  • Most chest CTs do not require contrast
  • Common indications for contrast:
    1. Mediastinal mass
    2. Lymphoma
    3. Lymphadenopathy 
    4. Pneumomediastinum (to assess for associated mediastinitis)
    5. Empyema (initial study)
    6. PE or dissection study

Routine Chest (~ 7 mSv)

“Standard Chest” 
Supraclavicular region to adrenal glands
C- / CO- is routine for nodules
C+ 25-30 sec / CO- for LAD, MS mass, abscess, or empyema
C+ / CO+ on table for gastric or esophageal pathology

Low Dose Screening
C- / CO- 
2mm x 2mm
Lung cancer screening, request specifies low dose CT, Chest Ct in young patient

Chest PE Protocol (~15 mSv vs. V/Q scan ~ 2.2 mSv)
“CTA Chest PE protocol”
Surestart PA ~ 16 sec
18-20 gauge antecubital @ 4mL/sec
Bolus tracking - ROI over pulmonary artery, with threshold set to 160HU

CTA Aortic Dissection 
”aortic dissection”
apices to bifurcation
C- / C+ 
Surestart aorta~20sec

Chest for ILD 
“ILD Protocol” 
Supine inspiration, supine expiration, prone inspiration
C- / CO-
Because the patient is scanned three times, the radiation dose is significantly higher than a routine chest CT.  If the supine is completely normal, then the patient does not need a prone. Consider writing in the comments to have the tech call after the supine to see if the prone is necessary (young patients).

Navigational Bronch
Add "navigational bronch" to protocol comments 
For thoracic surgeons: use a special navigational bronch tool that requires prep CT, essentially an inspiratory and expiratory CT


ER CT r/o appy protocol (NEW 1/2018)
An ED patient is be eligible for non-oral contrast Appendicitis protocol for CT of the Abdomen and Pelvis (IV contrast only) if all the following criteria are met:
1) Age ≥ 21 years
2) Serum creatinine less than or equal to 1.5
3) BMI greater than or equal to 25 kg/m^2
4) Absence of contrast allergy
5) Primary differential consideration is acute appendicitis

CT Abdomen/Pelvis (~14 mSv)
"routine A/P
diaphragm to pubis
exclude breast on young female with lower abd pain
C+ / CO+ ~70 sec
Additional 2 cups of contrast (if ordered with PO contrast) or 2 cups of water on the table

CT A/P during valsalva (include inguinal region or affected/ordered area)
C- / CO+ 
Give additional 2 cups PO contrast on table (okay if patient declines)

Retroperitoneal hemorrhage
include upper thighs if post femoral access)

GI Bleed/Mesenteric Ischemia (all 3 phases regardless of age)
"CT GI bleed"
2-3 cups of water on table
C- A/P
C+ 30 sec (arterial, for vascular map)
C+ 120 sec 
some IR attendings prefer delayed ~ 5 min phase as well
Trauma Protocol (decrease radiation dose by scanning once, ie inject contrast first to get urogram)
CT A/P “trauma protocol”
C+ A/P ~ 80 sec
no need for Cr level in trauma

Hematuria - tech must call when pt on table to check if ureters are fully opacified or more scans needed
“hematuria protocol”

under 50:
500mL water x 2 (30 min apart, last dose before pt goes on table)
split bolus IV contrast technique
C- A/P
C+ A/P 10 min 

over 50 (also same protocol for Transitional Cell Carcinoma):
500mL water x 2 (30 min apart, last dose before pt goes on table)
C- A/P
C+ A/P ~ 100 sec
C+ A/P ~ 15 min 

Renal Mass/tumor 
CT abd
2 cups water on table
C- abd 
C+ abd ~ 30 sec
C+ abd ~ 100 sec

Renal Calculus - patient is scanned PRONE
"CT kidney r/o stone"
2 cups water on table
C- kidneys and bladder (liver dome can be excluded)
Follow up stone: Low dose with fixed mA of 40 unless BMI >30

Kidney Donor
"CT kidney donor"
2 cups water on table
C- abd
C+ abd angiogram (done with bolus tracking)
C+ A/P ~ 100 sec
5 min scout at 5 min

Aortic Stent Graft (r/o stent graft leak or rupture) 
CT "Angiography - aortic endo graft"
2 cups water on table
C- A/P
C+ A/P ~ 30 sec
C+ A/P ~ 120 sec
1 mm fine cuts (McKinzie protocol)

Aortic Aneurysm 
2 cups water on table
C- for measurement of aneurysm only
If ordered with contrast: C- A/P and C+ A/P ~30sec
thoracic or abdominal 
If concerned about dissection, do aortic dissection protocol with contrast

Liver Mass (any liver mass w/wo prior procedures)
2 cups water on table
C- liver
C+ art liver ~ 30 sec
C+ PV A/P ~ 70 sec
C+ liver ~3min (can change to 5min delay for CCC and hemangioma)

Pancreatic mass
CT Abdomen “pancreatic tumor protocol”
2 cups water not table
C- abd
C+ arterial pancreas ~ 30s
C+ A/P ~ 70 sec

CT Virtual Colonoscopy
GoIytely 1 day prep 
C- A/P supine after air per rectum 
C- A/P prone after air per rectum 

CT Enterography (Crohns/UC/IBD, small bowel malignancy)
CO+ Volumen/water (450ml of Volumen 60, 45 and 30 mins prior to scanning, then 500ml of water 15 mins before scan)
C+ A/P ~70sec

Adrenal non-contrast
"CT Adrenal"
2 cups water on table
C- abd

Adrenal nodule washout
“adrenal washout” (scan thru adrenals)
2 cups water on table
C- abd
C+ abd 70 sec
C+ abd 15 min

DIEP flap (pre op flap planning)
2 cups water on table
C+ A/P ~ 30 sec (bolus tracking to external iliac artery)

CTA Lower extremity run-off
2 cups water on table
C- / C+ bifurcation to feet

CT venogram
2 cups water on table
C+ ~ 120sec
scan area depends on area of concern: abdomen, pelvis, lower extremities


  • SL: Protocol all cases in IDX
  • West: Protocol all CT cases in IDX, review all MR protocols with Dr. Lefton (or covering attending)

CT Head (~2 mSv)
C- for trauma, headache, AMS, stroke, seizure
C-/C+ for mass, infection/meningitis, but MRI with gad is better we do C- for detection of hemorrhage. Its difficult to r/o hemorrhage on a C+ only study.

CT Neck 
almost always C+
if evaluating thyroid, C-
if worried about foreign body, can be C- or C+

CT Sinus/Facial bone
check Rx to make sure they don't want stryker protocol protocol

CTA Head
C+ with MIPs by tech and better MIPs by you in Vitrea
for West inpatient 16 slice scanner, you must make MIPs yourself in Vitrea

CTA Neck
C+ with MIP images by tech
for carotid dissection, MRI with axial T1 fat sat is best to look for hyperintense crescent

CT Brain perfusion
C+ “perfusion protocol”
only on 64 slice scanner
must be 80kV

CT Spine
C- is routine
C+ for  r/o infection, post op
C- / C+ is sometimes ordered, should typically convert this to C+ only
RadRez Administrator,
Feb 17, 2015, 12:06 PM
RadRez Administrator,
Jan 11, 2016, 9:29 AM
RadRez Administrator,
Feb 17, 2015, 7:34 PM