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 APPENDICITIS 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

Dynamic imaging if needed Vascular tumor, accreta Delayed fat-suppressed T1W Infection, inflammation Gadolinium

APPENDIX ON MR Appendix seen in 10/12 pregnant patients with suspected appendicitis (AJR 2004;183:671-5) Thin slices and cross- referencing 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, right- sided pain

10 weeks pregnant, abdominal pain and fever COLITIS Courtesy of Aytekin Oto, M.D.

PELVIC ABSCESS

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

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