3  Protocols

The protocols used in this application were adapted from Ramathibodi emergency radiology handbook [1].

3.1 Body CT

3.1.1 CTWA

Protocol Phase Design Contrast

Routine WA
  • Venous (whole)
  • Delay (liver)

Oral (limited water), Rectal (water)
—
  • Plain (whole)
  • Late A (upper)
  • Venous (whole)
  • Delay (liver)

Oral (?), Rectal (?)

Solid Organ Rupture
  • Plain (whole)
  • Late A (upper)
  • Venous (whole)
  • Delay (upper)

No oral, No rectal

Free Air
  • Plain
  • Venous (may be)

Oral (positive), Rectal (positive) [If not stable -> no oral, no rectal]

GI Perforation
  • Venous
  • Delay (liver)

Oral (limited positive), Rectal (positive)

Gut Obstruction
  • Venous (whole)
  • Delay 3 min (liver)

No oral, No rectal

HBP mass/abscess (CTWA)
  • Plain (upper)
  • Late A (upper)
  • Venous (whole)
  • Delay (upper)

Oral (limited water), No rectal

Kidney mass/abscess
  • Plain (KUB)
  • Late A (upper)
  • Venous (100 sec)
  • Delay (KUB)

Oral (limited water), No rectal

GI Mass
  • Venous (whole)
  • Delay (liver)

Oral (full positive), Rectal (water)

Diverticulitis
  • Venous (whole)
  • Delay (liver)

Oral (limited water), Rectal (1 L, positive CM)

Pancreatitis
  • Plain (upper)
  • Late A (upper)
  • Venous (whole)
  • Delay (upper)

Oral (limited water), No rectal

Intra-abdominal infection
  • Plain (whole)
  • Late A (upper)
  • Venous (whole)
  • Delay (upper)

Oral (limited water), Rectal (water)

Leak-Fistula-Collection
  • Venous (whole)
  • Delay (liver)

Oral (if Hx bowel resect -> full positive; If not -> limited positive), Rectal (positive) ?

CT Second look Abd (trauma)
  • Venous (whole)

IV contrast, Oral (full positive), Rectal (positive)

3.1.2 CTA Whole Abdomen

Protocol Phase Design Contrast

GI Bleed
  • Plain (whole)
  • CTA (whole)
  • Venous (whole)
  • Delay (whole)

No oral, No rectal

Mesenteric Ischemia
  • Plain (whole)
  • CTA (whole)
  • Venous (whole)
  • Delay (whole)

Oral (limited water), Rectal (water)

AAA Rupture
  • Plain (whole)
  • CTA (maybe ถ้ามีเวลา คนไข้ stable)
  • Venous (maybe ถ้ามีเวลา คนไข้ stable)

No oral, No rectal

CTA Blunt Abdomen (trauma)
  • CTA (whole)
  • Venous (whole)
  • may be Delay (in injury site)

IV contrast, No oral, No rectal

CTA Penetrating Abd (trauma)
  • CTA (whole)
  • Venous (whole)
  • may be Delay (in injury site) *** วาง marker ตําแหน่งแผลด้วย

IV contrast, Oral & Rectal full positive (ถ้ามีเวลา)

3.1.3 CT Upper Abdomen

Protocol Phase Design Contrast

Routine Upper Abd
  • Venous (upper)
  • Delay (upper)

Oral (limited water), No rectal

HBP mass/abscess (Upper)
  • Plain (upper)
  • Late A (upper)
  • Venous (upper)
  • Delay (upper)

Oral (limited water), No rectal

Biliary Stone
  • Plain (upper)
  • Late A (upper)
  • Venous (upper)
  • Delay (liver)

Oral (limited water), No rectal

Adrenal mass/abscess
  • Plain (upper)
  • Late A (upper)
  • Venous (upper)
  • Delay 3 min (upper) *** Check ภาพ +/- Delay 15 min (adrenal)

Oral (limited water), No rectal

3.1.4 CT Lower Abdomen

Protocol Phase Design Contrast

Appendicitis
  • Venous 120 sec (L3 to pubic symphysis)

Rectal (Positive 1 L สวนถึง cecum), No oral

3.1.5 CT KUB

Protocol Phase Design Contrast

Hematuria
  • Plain (KUB)
  • Late A (Kidney)
  • Venous (KUB)
  • Delay (KUB) *** Check ภาพก่อนเลิก

Oral (limited water), No Rectal

Kidney mass/Abscess

*** If suspect renal mass → consider CTWA for staging - Plain (KUB) - Late A (Upper) - Venous (100 sec) - Delay (KUB) *** Check ภาพก่อนเลิก

Oral (limited water), No Rectal

In cases of suspected urothelial or renal tumor:

  • The patient should have a full bladder before undergoing a CT scan.
  • Consider clamping the Foley catheter or instilling NSS into the bladder for patients on continuous bladder irrigation (CBI).

3.1.6 CTA for PE

Protocol Phase Design Contrast

CTA for PE (ไม่ลากขา)
  • CTPA (chest)
  • Venous (chest)

IV contrast

CTA for PE with DVT
  • CTPA (chest)
  • Venous (chest, legs)

IV contrast

3.1.7 CT Chest

Protocol Phase Design Contrast

Routine CT Chest
  • maybe plain (chest)
  • Late A (chest)

IV contrast

Nodule/mass characterization
  • Plain (chest)
  • Late A (chest)

IV contrast

Tracheobronchomalacia
  • Plain (chest, dynamic expiration)

No IV contrast

Dysphagia
  • Plain (chest)
  • Venous (chest)

IV contrast, Oral (limited water)

CT esophagogram
  • Plain (Chest, reduced dose) ก่อนกิน CM
  • จากนั้น กิน CM 1 cup (250 ml) ที่เตียง
  • Venous (Chest) หลังกิน CM

Oral (Positive CM)

SVC Obstruction
  • Plain (Chest, reduced dose)
  • Late A (Chest)
  • Immediate delay (Chest)

IV contrast

3.1.8 CT Chest + WA

Protocol Phase Design Contrast
—
  • Plain (Chest + Whole abd)
  • Late A (Chest + Upper abd)
  • Venous (Whole abd)
  • Delay (liver)

Oral (?), Rectal (?)

3.1.9 CTA Chest

Protocol Phase Design Contrast

Hemoptysis
  • Plain (Chest)
  • CTA (Apex to L2) → Systemic arterial phase
  • Immediate delay (Chest)
  • Note: L2 (Celiac Axis) ให้เห็น renal artery origin

IV contrast

CTA Chest (trauma)
  • CTA (Chest)
  • Venous (Chest)

IV contrast, No Oral, No Rectal

3.1.10 CTA Whole Aorta

Protocol Phase Design Contrast

Aorta first time
  • Plain (whole aorta)
  • CTA (whole aorta)
  • Immediate delay (whole aorta)

IV contrast

Aortic Dissection
  • Plain (whole aorta)
  • CTA (whole aorta)
  • Immediate delay (whole aorta)

IV contrast

AAA Post-op
  • Plain (whole aorta)
  • CTA (whole aorta)
  • Immediate delay (whole aorta)

IV contrast

3.1.11 CTA Runoff

Protocol Phase Design Contrast

CTA Runoff

ขา → Aortic bifurcation to feet แขน → mid-heart to hands - Plain - CTA - Immediate delay

IV contrast

CTA Runoff (< 60 yr)

ขา → Aortic bifurcation to feet แขน → mid-heart to hands - CTA - Immediate delay

IV contrast

3.2 Neuro CT

Exam Protocol Phase Design Contrast

CT Brain (non-contrast)

 — —

No IV contrast

CTA Brain

Intracranial aneurysm
  • Plain, CTA, post-contrast (Brain)

IV contrast

CTV Brain

Venous Sinus Thrombosis
  • Plain, CTV, post-contrast (Brain)

IV contrast

CT Brain with Contrast

 —
  • Plain, post-contrast (Brain)

IV contrast

3.3 Trauma CT

Exam Protocol Phase Design Contrast

CTA Chest

CTA Chest (trauma)
  • CTA (Chest)
  • Venous (Chest)

IV contrast, No Oral, No Rectal

CTA Neck

CTA Neck (trauma)
  • CTA (brain, neck) COW to arch
  • Post-contrast (brain)

IV contrast

CT Facial Bone (non-contrast)

CT Facial Bone (trauma)
  • CT Facial Bones (plain) with 3D reformats

No IV contrast

CT Orbit (non-contrast)

CT Orbit (trauma)

 —

No IV contrast

CTA Whole Abd

CTA Blunt Abdomen (trauma)
  • CTA (whole)
  • Venous (whole)
  • may be Delay (in injury site)

IV contrast, No oral, No rectal

CTA Whole Abd

CTA Penetrating Abd (trauma)
  • CTA (whole)
  • Venous (whole)
  • may be Delay (in injury site) *** วาง marker ตําแหน่งแผลด้วย

IV contrast, Oral & Rectal full positive (ถ้ามีเวลา)

CTWA

CT Second look Abd (trauma)
  • Venous (whole)

IV contrast, Oral (full positive), Rectal (positive)