Thread by @DavidJHur1

#SCCT2021 "Chance Favors the Prepared: Exam Prep & Safety" #YesCCT Rad to the 🦴(🫁 🫀) by Dr. Andrew Einstein @AndrewEinstein7 @CU_Cardiology
🧵:

#SCCT2021 #YesCCT
1) Dosimetry
☢️effects: Deterministic & Stochastic
Deterministic (AKA tissue reactions): rad-induced cell☠️, practical threshold dose, severity ⬆️w/ dose
Stochastic: rad-induced mutations, risk proport to dose (@ low doses), typical effects in DX imaging

#SCCT2021 #YesCCT
2) Dose
- Absorbed: average E imparted to matter vol by ionizing☢️/ mass of matter in vol
- wR:🧬effect of given absorb. dose based on type/quality of☢️emitted
- Equivalent = Absorbed✖️wR
- wT: prob of stochastic effects of equiv. dose based on tissue irradiatd

#SCCT2021 #YesCCT
3) Dose cont'd
- Weighted Equivalent = Equivalent✖️wT
- Effective = sum of Weighted Equivalent doses
- for CT: DLP = volume CTDI✖️length irradiated
- traditional: Effective = DLP✖️conversion factor (0.014), but...

#SCCT2021 #YesCCT
4) Is k-factor of 0.014 invoked in older guidelines outdated?
- in contemp studies using modern dosimeters & physical anthropomorphic phantoms, k-factors ranged 0.020-0.043
- as of 2018, for adult CT exams confined to 🫀, average k-factor ought to be 0.026

#SCCT2021 #YesCCT
5) Effective doses remain variable and high, and thus there remains ongoing push to keep bringing doses down further