APPENDICITIS
• Most common non-OB surgical condition
• Fetal loss >30% if ruptured, <2% if not
• Difficult clinical diagnosis:
• Majority of cases afebrile
• Physiologic increase WBC
6-16,000 & up to 30,000 in labor
• N/V common in pregnancy
• Site of pain may be unusual
Ax T1w: normal appendix
MR SAFETY
RECOMMENDATIONS
•
•
•
•
No known adverse fetal effects
Safety concern: energy deposition
MR only if US not adequate
Depending on risk/benefit:
• Avoid MR in first trimester
• Avoid Gadolinium
(FDA pregnancy category C)
Preparation & Positioning
• NPO x 4 hours
• Supine or decubitus position
• LLD: better for IVC compression
• Phased array coil
• Large patient: 2 phased array or body coil
Maternal MR: Technique
• 3 plane 6mm T2w
HASTE (Seimens) or
SSFSE (GE)
• Coronal, axial T2/T1w
True-FISP
• Review to determine
need for additional
sequences or
gadolinium
Additional Noncontrast Sequences
• Fat-suppressed T2w
• Inflammation, especially if no gad
• T1w or fat-suppressed T1w
• Blood products, fat vs. blood, endometriosis
• Thick slab T2w echo train spin echo
• MRCP, MR Urography
• Phase contrast/time of flight: vascular
Gadolinium
• Dynamic imaging if needed
Vascular tumor, accreta
• Delayed fat-suppressed T1W
Infection, inflammation
APPENDIX ON MR
Appendix seen in 10/12
pregnant patients with
suspected appendicitis
(AJR 2004;183:671-5)
Thin slices and crossreferencing tool helpful
APPENDICITIS
Pregnant with
abdominal pain
T2w
T2w FS
34 yo RLQ pain
DEGENERATING FIBROID
Courtesy of Aytekin Oto, M.D.
RUPTURED APPENDICITS
Courtesy of Aytekin Oto, M.D.
RUPTURED APPENDICITIS
33 yo at 31
weeks, rightsided pain
10 weeks pregnant, abdominal pain and fever
COLITIS
Courtesy of Aytekin Oto, M.D.
PELVIC ABSCESS
Courtesy of Aytekin Oto, M.D.
DIVERTICULAR
ABSCESS
ULCERATIVE COLITIS
PERITONITIS
Pregnant, history of
Crohn dz now with
pain and fever
DEGENERATING
FIBROID
Fibroids & Pregnancy
• Pain during pregnancy can be severe
• Rapid growth
• Degeneration
• Torsion
• Degeneration may lead to premature labor
DEGENERATING FIBROID
35 yo 19 weeks pregnant with severe RLQ pain
DEGENERATING FIBROID
SHORT CERVIX
18 yo 17 weeks
pregnant, RLQ pain x 2
mos, now acutely worse
TORSED FIBROID
Surgery: pedunculated fibroid, stalk twisted 360 degrees
SMALL BOWEL OBSTRUCTION
• Adhesions > volvulus >> other causes
• High incidence of necrotic bowel
• Fetal mortality 20-26%
• Only 1/3 complete to term after surgery
• Most significant contributor to mortality:
delayed diagnosis and treatment
• MR: Ultra-fast sequences (HASTE, FISP)
helpful due to minimal motion artifact
30 yo at 36 weeks with abdominal & pelvic pain
SMALL BOWEL OBSTRUCTION
Surgery: sbo, multiple adhesions
INTUSSUSCEPTION
Pregnant with abdominal
and pelvic pain, nausea
and vomiting
CHOLECYSTITIS
OVARIAN TORSION
• Pregnant women predisposed to torsion
• Ultrasound diagnostic unless ovaries
poorly visualized due to pregnancy
• MR appearance: enlarged ovary with
increased stromal SI on T2w
• Increased SI on T1w suggests
hemorrhage or vascular congestion
• Gadolinium may be diagnostic
OVARIAN TORSION
Courtesy of David McFadden, MD
25 yo 15 weeks pregnant with RLQ pain
OVARIAN TORSION
T2w
OVARIAN TORSION
25 yo 15 weeks pregnant
with RLQ pain and adnexal
mass on ultrasound
PYELONEPHRITIS
19 yo pregnant woman with right-sided pain and fever
Sickle Beta
Thalassemia