Screening OB Ultrasound • Xray of the Week 2016 • Week #39 This 28 year old had a routine OB ultrasound. What is the abnormality? What is the significance of this finding? Fig 1A: Prenatal ultrasound. Coronal head. Absence of the calvarium and brain with associated bulging orbits giving the "frog eye" appearance. Fig 1B: Prenatal ultrasound. Sagittal head and neck. Absence of the calvarium and brain. Anencephaly is the most severe neural tube defect (NTD) with complete absence of most of the cranium, meninges, and calvarium due to failure of closure of the rostral neural tube. All women of child-bearing age should consume 0.4 mg of folic acid daily, especially those attempting to conceive or who may possibly conceive, as this can reduce the risk of anencephaly from 0.1 % to 0.03%. Genetics may play a role in the cause of anencephaly as women with a prior pregnancy with NTD have a 3% risk of having another child with a NTD. Other possible factors include insulin-dependent diabetes, exposure to anticonvulsants, and toxins such as lead, chromium, mercury, and nickel. Antenatal screening for NTD’s with ultrasound and maternal serum alpha-fetoprotein is essentially 100% effective. With ultrasound, no brain parenchymal tissue is seen above the orbits and the calvarium is largely absent. As in this case, coronal ultrasound of the head demonstrates absence of the calvarium and brain with associated bulging orbits giving the "frog eye" appearance. [Fig.1A] Associated findings on ultrasound may include: other neural tube defects such as spina bifida, congenital heart defects, cleft lip/palate, diaphragmatic hernia, spinal dysraphism, clubfoot, omphalocele, and urinary tract anomalies such as hydronephrosis. Prognosis is dismal with 100% fatality, most within the first few hours after delivery. References: 1. Cameron M, Moran P. Prenatal screening and diagnosis of neural tube defects. Prenat Diagn. 2009 Apr;29(4):402-11 2. Goldstein RB, Filly RA. Prenatal diagnosis of anencephaly: spectrum of sonographic appearances and distinction from the amniotic band syndrome. AJR Am J Roentgenol. 1988;151 (3): 547-50. 3. Morbidity and Mortality Weekly Report (MMWR). Effectiveness in Disease and Injury Prevention Use of Folic Acid for Prevention of Spina Bifida and Other Neural Tube Defects -- 1983-1991 http://www.cdc.gov/mmwr/preview/mmwrhtml/00014915.htm 4. Timor-tritsch IE, Greenebaum E, Monteagudo A et-al. Exencephaly-anencephaly sequence: proof by ultrasound imaging and amniotic fluid cytology. J Matern Fetal Med. 5 (4): 182-5. Kevin Rice, MD serves as the Medical Director of the Radiology Department of Valley Presbyterian Hospital in Los Angeles, California and is a Member of Renaissance Imaging Medical Associates. Dr. Rice has made several media appearances as part of his ongoing commitment to public education. Dr. Rice's passion for state of the art radiology and teaching includes acting as a guest lecturer at UCLA. In 2015 Dr. Rice launched Global Radiology CME to provide innovative radiology education at exciting international destinations, with the world's foremost authorities in their field. Follow Dr. Rice on Twitter @KevinRiceMD All Posts by Kevin M Rice, MD

Screening OB Ultrasound • Xray of the Week 2016 • Week #40 This 26 year old had a routine OB ultrasound. What is the abnormality? What is the treatment? Figure 1: Gastroschisis on prenatal ultrasound. Note the herniated small bowel to the right of the cord insertion. The bowel is freely floating in the amniotic fluid. Gastroschisis is a sporadic congenital anomaly characterized by herniation of fetal abdominal contents, usually small bowel, and occasionally stomach, colon and/or liver into the amniotic cavity through a para-umbilical abdominal wall defect. The incidence is approximately 1 per 10,000 live births. With the defect almost always on the right side and typically 2-4 cm long, unlike omphalocele, there is no covering membrane. Associated anomalies (usually malrotation) are seen only in 10% of cases; however, omphalocele has associated anomalies in 27-91% of cases. Figure 2: Omphalocele. The cord inserts at the apex of the abdominal wall defect and the abdominal contents are covered by a membrane. Case courtesy of Dr Ahmed Mahrous Saied, Radiopaedia.org. From the case https://radiopaedia.org/cases/34001 On prenatal ultrasound, the fetal abdominal circumference is small for gestational age due to the herniated abdominal contents. The small bowel is seen to be free floating in the amnionic fluid to the right of the umbilical cord insertion [Figure 1]. With omphalocele, the cord inserts at the apex of the abdominal wall defect and the herniated abdominal contents are covered by a membrane [Figure 2]. Most infants with gastroschisis are treated surgically on the first day of life, however, 90% of cases require multiple operations. The prognosis is good with a survival rate of greater than 90%. References: 1. Morrow RJ, Whittle MJ, McNay MB, Raine PA, Gibson AA, Crossley J (1993). "Prenatal diagnosis and management of anterior abdominal wall defects in the west of Scotland". Prenat Diagn. 13(2): 111–5. 2. Shaw, Anthony (1975). "The myth of gastroschisis". Journal of Pediatric Surgery. 10 (2): 235–44. 3. Devries, Pieter A. (1980). "The pathogenesis of gastroschisis and omphalocele". Journal of Pediatric Surgery. 15 (3): 245–51. 4. Santiago-Munoz PC, McIntire DD, Barber RG, Megison SM, Twickler DM, Dashe JS (2007)."Outcomes of pregnancies with fetal gastroschisis". Obstet Gynecol. 110 (3): 663–8. 5. Baerg J, Kaban G, Tonita J, Pahwa P, Reid D (2003). "Gastroschisis: A sixteen-year review". J Pediatr Surg. 38 (5): 771–4. 6. http://www.cdc.gov/ncbddd/birthdefects/gastroschisis.html 7. Blazer S, Zimmer EZ, Gover A et-al. Fetal omphalocele detected early in pregnancy: associated anomalies and outcomes. Radiology. 2004;232 (1): 191-5. 8. Durfee SM, Downard CD, Benson CB et-al. Postnatal outcome of fetuses with the prenatal diagnosis of gastroschisis. J Ultrasound Med. 2002;21 (3): 269-74. 9. Giulian, BB. Prenatal Ultrasonographic Diagnosis of Fetal Gastroschisis. Radiology 129:473-475, November 1978 10. Daltro P, Fricke BL, Kline-fath BM et-al. Prenatal MRI of congenital abdominal and chest wall defects. AJR Am J Roentgenol. 2005;184 (3): 1010-6. Kevin Rice, MD serves as the Medical Director of the Radiology Department of Valley Presbyterian Hospital in Los Angeles, California and is a Member of Renaissance Imaging Medical Associates. Dr. Rice has made several media appearances as part of his ongoing commitment to public education. Dr. Rice's passion for state of the art radiology and teaching includes acting as a guest lecturer at UCLA. In 2015 Dr. Rice launched Global Radiology CME to provide innovative radiology education at exciting international destinations, with the world's foremost authorities in their field. Follow Dr. Rice on Twitter @KevinRiceMD All Posts by Kevin M Rice, MD

Vote for the Correct Spine Labeling • Xray of the Week 2016 • Week #46 RADIOLOGISTS - It's not too late to vote! This could have serious consequences for several years. If you do not like either of the major candidates, please pick C. To vote, reply with A or B, or C in the comments. Sorry, but there are no secret ballots. The votes will be tallied, and the winner announced on Friday. Fig. 1. A & B: Two ways of labeling the same image. Either one could be correct Fig. 1. C: "I do not know" is the correct answer. Transitional lumbosacral vertebrae are a relatively common variant and can be seen in 15-35% of the general population [1-3]. If this variant is not recognized or not correctly described in the report, there is a risk of wrong level surgery or other spine intervention such as injection [3,4]. It is essential to evaluate all preoperative imaging modalities before reporting the levels on intraoperative images. If preoperative images are not available and the surgeon is insistent on providing a level in the report, we use the following preamble: "For the purposes of this report, the last apparent true disc level is considered to be L5-S1. Based on this, the posterior surgical instrument is present overlying the ___ level." If there is no absolute requirement to state a level in the report, one can use the following verbiage: "This ia a limited lateral intraoperative radiograph for the purpose of localization. Please refer to the operative report including designation of the operative levels by the surgeon." Fig. 2. The iliolumbar ligaments (blue arrows). The iliolumbar ligament is fairly reliable anatomic structure which can be used to determine the lumbosacral numbering scheme (Fig. 2). Best seen on CT scan, the iliolumbar ligament frequently arises from the transverse process of L5. However, due to wide variability in the number of vertebral segments, the iliolumbar ligament does not always indicate the L5 level. It actually merely identifies the lowest lumbar-type vertebral segment [1]. References: 1. Carrino JA, Campbell PD, Lin DC et-al. Effect of Spinal Segment Variants on Numbering Vertebral Levels at Lumbar MR Imaging. Radiology. 2011;259 (1): 196-202. 2. Uçar D, Uçar BY, Coşar Y et-al. Retrospective cohort study of the prevalence of lumbosacral transitional vertebra in a wide and well-represented population. Arthritis. 2013;2013: 461425. 3. Konin GP, Walz DM. Lumbosacral transitional vertebrae: classification, imaging findings, and clinical relevance. AJNR Am J Neuroradiol. 2010;31 (10): 1778-86. AJNR Am J Neuroradiol. 4. Bron JL, van Royen BJ, Wuisman PI. The clinical significance of lumbosacral transitional anomalies. Acta Orthop Belg. 2008;73 (6): 687-95. Kevin Rice, MD serves as the Chair of the Radiology Department of Valley Presbyterian Hospital in Los Angeles, California and is a radiologist with Renaissance Imaging Medical Associates. Dr. Rice has made several media appearances as part of his ongoing commitment to public education. Dr. Rice's passion for state of the art radiology and teaching includes acting as a guest lecturer at UCLA. In 2015 Dr. Rice launched Global Radiology CME to provide innovative radiology education at exciting international destinations, with the world's foremost authorities in their field. In 2016, Dr. Rice was nominated and became a semifinalist for a "Minnie" award for the Most Effective Radiology Educator. Follow Dr. Rice on Twitter @KevinRiceMD All Posts by Kevin M Rice, MD

Left Scrotal Pain in 64M • Xray of the Week 2016 • Week #50 This 64 year old male presented with left scrotal pain. There is a history of undescended left testicle and orchiopexy at age 5. What is the diagnosis? Video 1: Ultrasound demonstrating slow flow in an intratesticular varicocele. Video 2: Zoomed ultrasound demonstrating slow flow in an intratesticular varicocele. The flow is too slow to be seen with color Doppler. Figure 1. Intratesticular varicocele in a different patient. Color Doppler shows the dilated vein within the testis. Case courtesy of Dr Rupesh Namdev, Radiopaedia.org. From the case rID: 27305 Intratesticular varicocele is a rare cause of testicular pain seen in less than 2% of cases. Although usually associated with extratesticular varicocele, as seen in this case it is not invariable. Testicular pain is due to stretching of the tunica albuginea related to congestion and dilatation of veins [1]. Approximately 9% of men who have had prepubertal orchiopexy for undescended testis eventually develop an intratesticular varicocele [2]. Slightly more than half of the cases occur on the left side [1,2,3]. In 1992, Weiss et al reported the first 2 cases of intratesticular varicocele, describing straight or serpentine hypoechoic structures within the mediastinum testis radiating into the testicular parenchyma, identified as veins with color Doppler sonography [3]. However, slow flow may preclude Doppler signal, and as seen in the videos above, flow can be appreciated with real time sonography [Videos 1 and 2]. Approximately 80% of the testes affected with intratesticular varicocele demonstrate atrophy [4]. References: 1. Das KM, Prasad K, Szmigielski W et-al. Intratesticular varicocele: evaluation using conventional and Doppler sonography. Abstract: AJR Am J Roentgenol. 1999;173 (4): 1079-83. Full Text PDF 2. Meij-de Vries A, den Bakker FM, van der Wolf-de Lijster FS et-al. High prevalence of intratesticular varicocele in a post-orchidopexy cohort. J Pediatr Urol. 2013;9 (3): 328-33. doi:10.1016/j.jpurol.2012.04.004 - Pubmed citation 3. Weiss AJ, Kellman GM, Middleton WD, Kirkemo A. Intratesticular varicocele: sonographic findings in two patients. AJR Am J Roentgenol 1992; 158:1061–1063 4. Tétreau R, Julian P, Lyonnet D, et al. Intratesticular Varicocele: An Easy Diagnosis But Unclear Physiopathologic Characteristics. J Ultrasound Med 2007; 26:1767–1773 Kevin Rice, MD serves as the Medical Director of the Radiology Department of Valley Presbyterian Hospital in Los Angeles, California and is a Member of Renaissance Imaging Medical Associates. Dr. Rice has made several media appearances as part of his ongoing commitment to public education. Dr. Rice's passion for state of the art radiology and teaching includes acting as a guest lecturer at UCLA. In 2015 Dr. Rice launched Global Radiology CME to provide innovative radiology education at exciting international destinations, with the world's foremost authorities in their field. In 2016, Dr. Rice was nominated and became a semifinalist for a "Minnie" award for the Most Effective Radiology Educator. Follow Dr. Rice on Twitter @KevinRiceMD All Posts by Kevin M Rice, MD

6 Month Old with Abdominal Pain • Xray of the Week History: There was a baby from Cali, who had a pain in his belly. For a BE, it's time; 'cause of a target sign, and his stool looks like currant jelly. Figure 1. Left image: Target sign on ultrasound due to intussusception. Right image: Spot view from water soluble contrast enema showing the filling defect in the transverse colon due to ileo-colic intussusception. Figure 2. The pseudokidney sign. Long axis ultrasound image of intussusception showing the layers of ileum inside the cecum in the right lower quadrant. Figure 3. Intussusception is reduced with contrast in the terminal ileum. Figure 4. Actual currant jelly Figure 5. Bloody stool in diaper (aka nappy) that looks like currant jelly Intussusception is a common cause of abdominal pain in children and is caused by a segment of bowel pulled into itself by peristalsis. The classic triad of intermittent abdominal pain, vomiting and right upper quadrant mass, plus occult or gross blood on rectal examination is seen in less than 20% of intussusception cases. Bloody stool may have the appearance of currant jelly due to the presence of mucus in the stool [Fig. 4,5]. If prolonged, ischemia and necrosis with eventual perforation may occur. 90% of cases in children aged less than 2 years old have no lead point. Ultrasound demonstrates the target sign in the short axis view [Fig. 1] and the pseudokidney sign in the long axis view [Fig.2] due to alternating bands of hyperechoic mucosa and hypoechoic submucosa. Definitive diagnosis and treatment is reduction with water soluble contrast or air enema [Fig. 3]. When seen in adults, there is almost invariably a neoplasm as a pathologic lead point, thus requiring surgery. References: 1. Lioubashevsky N, Hiller N, Rozovsky K, et al. Ileocolic versus Small-Bowel Intussusception in Children: Can US Enable Reliable Differentiation? Radiology. 269 (3): 266-271 2. Kim YH, Blake MA, Harisinghani MG et-al. Adult intestinal intussusception: CT appearances and identification of a causative lead point. Radiographics. 26 (3): 733-44 3. Anderson DR. The pseudokidney sign. Radiology. 1999;211 (2): 395-7. 4. del-Pozo G, Albillos JC, Tejedor D, et al. Intussusception in children: current concepts in diagnosis and enema reduction. RadioGraphics 1999;19(2):299–319. 5. Swischuk LE, Hayden CK, Boulden T. Intussusception: indications for ultrasonography and an explanation of the doughnut and pseudokidney signs. Pediatr Radiol 1985;15(6):388–391. 6. Rubinstein JC, Lucy Liu L, Caty MG. Pathologic Leadpoint Is Uncommon in Ileo-Colic Intussusception Regardless of Age. J Pediatr Surg. 2015 Oct;50(10):1665-7. DOI: 10.1016/j.jpedsurg.2015.03.048 7. McDermott VG, Taylor T, Mackenzie S, et al. Pneumatic Reduction of Intussusception: Clinical Experience and Factors Affecting Outcome. Clin Radiol. 1994 Jan;49(1):30-4. doi: 10.1016/s0009-9260(05)82910-1. Related case: Intussusception in melanoma Kevin Rice, MD serves as the Chair of the Radiology Department of Valley Presbyterian Hospital in Los Angeles, California and is a radiologist with Renaissance Imaging Medical Associates. Dr. Rice has made several media appearances as part of his ongoing commitment to public education. Dr. Rice's passion for state of the art radiology and teaching includes acting as a guest lecturer at UCLA. In 2015 Dr. Rice founded Global Radiology CME to provide innovative radiology education at exciting international destinations, with the world's foremost authorities in their field. In 2016, Dr. Rice was nominated and became a semifinalist for a "Minnie" award for the Most Effective Radiology Educator. Follow Dr. Rice on Twitter @KevinRiceMD All Posts by Kevin M Rice, MD

Here's all my 2016 cases in one quick video: Kevin Rice, MD serves as the Chair of the Radiology Department of Valley Presbyterian Hospital in Los Angeles, California and is a radiologist with Renaissance Imaging Medical Associates. Dr. Rice has made several media appearances as part of his ongoing commitment to public education. Dr. Rice's passion for state of the art radiology and teaching includes acting as a guest lecturer at UCLA. In 2015 Dr. Rice founded Global Radiology CME to provide innovative radiology education at exciting international destinations, with the world's foremost authorities in their field. In 2016, Dr. Rice was nominated and became a semifinalist for a "Minnie" award for the Most Effective Radiology Educator. Follow Dr. Rice on Twitter @KevinRiceMD All Posts by Kevin M Rice, MD

Let's stop the confusion! There is no Superficial Femoral Vein! Many ultrasound technologists are using the term "superficial femoral vein" or "SFV" on their images. In addition, radiologists often use this term in reports. To the best of my knowledge, there is actually no such anatomic structure. The name of the vein between the common femoral vein (CFV) and popliteal vein is the "femoral vein" (FV) [1-4]. Figure 1. A. The ultrasound technologist has incorrectly labeled the image "SFV". B. A different ultrasound technologist has correctly labeled the image "FV". This misnomer has real consequences - I have personally seen patients not treated for acute DVT as the report has indicated isolated thrombus in the superficial femoral vein. The clinician read the report and thought he did not need to treat the patient with anticoagulants as it was superficial thrombosis. I would encourage all ultrasound technologists and radiologists to abandon the term "Superficial Femoral Vein" and instead use the term used by the vast majority of anatomists [4], endorsed by The Society of Interventional Radiology (SIR) [3], The Australasia Society for Ultrasound in Medicine (ASUM) [5], and The Interventional Radiology Society of Australasia (IRSA) [6]: "Femoral Vein". Figure 2. Venous anatomy of the lower extremity demonstrating the femoral vein. Note that it is the vein between the common femoral vein and the popliteal vein. There is no superficial femoral vein. References: 1. Hammond I. The Superficial Femoral Vein [letter] Radiology. November 2003. Volume 229, Issue 2 p.604. 2. Thiagarajah R, Venkatanarasimha N, Freeman S. Use of the term "superficial femoral vein" in ultrasound. J Clin Ultrasound. 2011 Jan;39(1):32-4. 3. Caggiati A, Bergan JJ, Gloviczki P, Jantet G, Wendell-Smith CP, Partsch H, et al. Nomenclature of the veins of the lower limbs: an international interdisciplinary consensus statement. Journal of Vascular Surgery. 2002;36(2):416-222. 4. Bundens WP, Bergan JJ, Halasz NA, Murray J, Drehobi M. The superficial femoral vein: a potentially lethal misnomer. JAMA. 1995;274:1296–1298.3. 5. Australasia Society for Ultrasound in Medicine (ASUM). Statement on Use of ‘Superficial Femoral Vein’ Term. http://hosted.verticalresponse.com/1278897/74615a8ee1/545444629/804d8fbe22/ 6. Interventional Radiology Society of Australasia (IRSA). Use of the term “superficial femoral vein”. http://www.irsa.com.au/news/76-use-of-the-term-superficial-femoral-vein. Kevin Rice, MD serves as the Medical Director of the Radiology Department of Valley Presbyterian Hospital in Los Angeles, California and is a Member of Renaissance Imaging Medical Associates. Dr. Rice has made several media appearances as part of his ongoing commitment to public education. Dr. Rice's passion for state of the art radiology and teaching includes acting as a guest lecturer at UCLA. In 2015 Dr. Rice launched Global Radiology CME to provide innovative radiology education at exciting international destinations, with the world's foremost authorities in their field. Due to his online teaching activities, Dr. Rice was nominated and became a semifinalist for a "Minnie" award for the Most Effective Radiology Educator in 2016. Follow Dr. Rice on Twitter @KevinRiceMD All Posts by Kevin M Rice, MD

Thyroid Nodule • Xray of the Week 2017 • Week #40 What is the TI-RADS Score of this nodule? What would you do next? Figure 1: Thyroid Ultrasound. TI-RADS Scoring Here is how I scored it: Composition: Solid or almost completely solid - 2 points Echogenicity: Hypoechoic - 2 points Shape: Taller-than-wide - 3 points Margin: Lobulated or irregular - 2 points Echogenic Foci: Punctate echogenic foci - 3 points TOTAL: 12 TIRADS 5 - Highly Suspicious, Needs FNA. Biopsy was performed and it showed thyroid papillary cancer. Figure 2: Thyroid Ultrasound. Arrows showing the punctate echogenic foci. The ACR Thyroid Imaging Reporting and Data System (TI-RADS) is a system that can take the guess work out of reading thyroid ultrasounds. The goal is to improve quality and decrease unnecessary biopsies. Figure 3: ACR TI-RADS System More TI-RADS Resources here: https://www.globalradcme.com/acr-tirads-resources References: 1. ACR TI-RADS ATLAS 2. Grant, E G, Tessler, FN, Hoang, JK, Langer, JE, Beland, MD, Berland, LL, Cronan JJ, Desser, TS, Frates, MC, Hamper, UM, Middleton, WD, Reading, CC, Scoutt, LM, Stavros, AT and Teefy, SA. (2015). Thyroid Ultrasound Reporting Lexicon: White Paper of the ACR Thyroid Imaging, Reporting and Data System (TIRADS) Committee. Journal of the American College of Radiology,12(12), 1272-1279. http://www.jacr.org/article/S1546-1440(15)00684-5/abstract 3. Franklin N. Tessler, MD, CMCorrespondence information about the author MD, CM Franklin N. TesslerEmail the author MD, CM Franklin N. Tessler, William D. Middleton, MD, Edward G. Grant, MD, Jenny K. Hoang, MBBS, Lincoln L. Berland, MD, Sharlene A. Teefey, MD, John J. Cronan, MD, Michael D. Beland, MD, Terry S. Desser, MD, Mary C. Frates, MD, Lynwood W. Hammers, DO, Ulrike M. Hamper, MD, Jill E. Langer, MD, Carl C. Reading, MD, Leslie M. Scoutt, MD, A. Thomas Stavros, MD ACR Thyroid Imaging, Reporting and Data System (TI-RADS): White Paper of the ACR TI-RADS Committee. http://www.jacr.org/article/S1546-1440(17)30186-2/fulltext Kevin Rice, MD serves as the Chair of the Radiology Department of Valley Presbyterian Hospital in Los Angeles, California and is the Chief Compliance Officer of Renaissance Imaging Medical Associates. Dr. Rice has made several media appearances as part of his ongoing commitment to public education. Dr. Rice's passion for state of the art radiology and teaching includes acting as a guest lecturer at UCLA. In 2015 Dr. Rice co-founded Global Radiology CME to provide innovative radiology education at exciting international destinations, with the world's foremost authorities in their field. Follow Dr. Rice on Twitter @KevinRiceMD All Posts by Kevin M Rice, MD

Transient Left Eye Blindness after Exercise • Xray of the Week This 73 year old male with a history of transient left eye blindness after exercise had a carotid doppler with evaluation of the ophthalmic arteries. What is the abnormality and what is the anatomic reason? Fig. 1A: No flow in the left internal carotid artery. Fig. 1B: Antegrade flow in the right ophthalmic artery. Note red color above the baseline in the ophthalmic artery. The pulsed Doppler signal is also above the baseline. Fig. 1C: Retrograde flow in the left ophthalmic artery. Note blue color below the baseline in the ophthalmic artery. The pulsed Doppler signal is also below the baseline. Fig. 2A. Normal flow direction shown with arrows in the arteries. There is normal antegrade flow in the ophthalmic artery (OA), signified by the red arrow. Fig. 2B Note the retrograde flow in the ophthalmic artery (OA), signified by the blue arrow. With occlusion of the internal carotid artery (ICA), peri-orbital collaterals from the ECA circulation open up, and flow is restored to the supra-clinoid segment of the ICA. Key: CCA: Common carotid artery ECA: External carotid artery ICA: Internal carotid artery FA: Facial artery AA: Angular artery STA: Superficial temporal artery STA (FA): Superficial temporal artery (Frontal artery-branch) OA: Ophthalmic artery STA: Supratrochlear artery Fig. 3. Neovascularization of the iris (NVI), also known as rubeosis iridis, is when small fine, blood vessels (black arrows) develop on the anterior surface of the iris in response to retinal ischemia. These changes most often develop at the pupillary border (yellow arrow). Ophthalmic Image by EyeRounds.org, The University of Iowa is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License. Discussion Retrograde flow in the ophthalmic artery can be seen with ICA occlusion or severe stenosis and may lead to transient orbital ischemia. (1,2,3) Due to the decreased flow to the globe, this may present as transient monocular blindness after exposure to bright light, position-induced visual loss, postprandial transient visual loss, exercise-induced visual loss, or visual loss following facial heating.(1,2,3) Patients with markedly diminished flow to the globe may eventually develop rubeosis iridis (Fig.3) which is defined as neovascularization of the iris in response to retinal ischemia.(3,4) This may in turn lead to the development of neovascular glaucoma. Therefore, these patients should be treated with superficial temporal artery to middle cerebral artery (STA-MCA) bypass to avoid this serious complication.(3) References: 1. Anupriya Arthur, et al. Ophthalmic masquerades of the atherosclerotic carotids. Indian Journal of Ophthalmology. 2014. Volume 62, Page 472-476 2. Yamamoto K, Mori T, Yasuhara M, et al. Ophthalmic artery blood flow in patients with internal carotid artery occlusion. Br J Ophthalmol. 2004 Apr; 88(4): 505–508. doi: 10.1136/bjo.2003.025809 3. CL Tsai, et al. Reversal of ophthalmic artery flow as a predictor of intracranial hemodynamic compromise: implication for prognosis of severe carotid stenosis. European Journal of Neurology Volume 20, Issue 3, pages 564–570, March 2013 4. Beebe, J and Haugsdal J. Rubeosis iridis or neovascularization of the iris in diabetes. Accessed 11/10/2018. EyeRounds.org. https://webeye.ophth.uiowa.edu/eyeforum/atlas/pages/NVI/index.htm Kevin Rice, MD is the president of Global Radiology CME and serves as the Chief of Staff and Chair of the Radiology Department at Valley Presbyterian Hospital in Los Angeles, California and is a Radiologist with Renaissance Imaging Medical Associates. Dr. Rice has made several media appearances as part of his ongoing commitment to public education. Dr. Rice's passion for state of the art radiology and teaching includes acting as a guest lecturer at UCLA. In 2015 Dr. Rice co-founded Global Radiology CME with Natalie Rice to provide innovative radiology education at exciting international destinations, with the world's foremost authorities in their field. In 2016, Dr. Rice was nominated and became a semifinalist for a "Minnie" Award for the Most Effective Radiology Educator. Follow Dr. Rice on Twitter @KevinRiceMD All Posts by Kevin M Rice, MD

Name the Device • Xray of the Week Routine CXR for cough demonstrates metallic device. Name the cardiac implant. Fig. 1 Device is within the myocardium of the right ventricle and is an implanted cardiac pacemaker. Fig. 2 A different patient with 2 cardiac devices. Device A is within the myocardium of the right ventricle and is an implanted pacemaker. Device B is within the chest wall and is an implanted cardiac loop recorder. Fig. 3 CT scan of a different patient with a Micra intracardiac pacemaker within the myocardium of the right ventricle. Fig 4. The Micra intracardiac pacemaker. Fig 5. Video showing the technique for implantation of the leadless cardiac pacemaker. The Micra™ transcatheter pacing system (TPS) is the world’s smallest pacemaker, (1) delivered percutaneously via a minimally invasive approach, directly into the right ventricle and does not require the use of leads. It has a 99% implant success rate (2,3) and 63% fewer major complications than traditional pacemakers. (3) The Micra Pacing Capsule is 93% smaller than conventional pacemakers (4) and has an estimated average 12-year battery longevity.(2,5) The device is MRI safe up to 3 Tesla. (2). References: 1. Nippoldt D, Whiting J. Micra Transcatheter Pacing System: Device Volume Characterization Comparison. November 2014. Medtronic Data on File. 2. Reynolds DW, Duray GZ, Omar R, et al. A Leadless Intracardiac Transcatheter Pacing System. N Engl J Med. Published online November 9, 2015. 3. El-Chami M, et al. Leadless Pacemaker Implant in Patients with Pre-Existing Infections: Results from the Micra Post-Approval Registry. Presented at HRS May 2018. Boston, MA 4. Williams E, Whiting J. Micra Transcatheter Pacing System Size Comparison, November 2014, Medtronic Data on File. 5. Duray GZ. Ritter P, el-Chami M, et al. Long-term performance of a transcatheter pacing system: 12-Month results from the Micra Transcatheter Pacing Study. Heart Rhythm. Published online February 10, 2017. 6. Medtronic Micra Implant Manual, April, 2015 7. Eggen M, Grubac V, Bonner M. Design and Evaluation of a Novel Fixation Mechanism for a Transcatheter Pacemaker. IEEE Trans Biomed Eng. September 2015;62(9):2316-2323. 8. Eggen, M. FlexFix Tine Design. April 2015. Medtronic Data on File. 9. Bonner M, et al. Pacing Clin Electrophysiol. 2015;38:1248-1259. 10. Medtronic Micra Transcatheter Pacing System Website Related posts: Bicuspid Aortic Valve and Aortic Stenosis Implanted Cardiac Loop Recorder Cardiac Tamponade Following Coronary Artery Rotational Atherectomy Papillary Fibroelastoma of Aortic Valve CardioMEMS Device Kevin M. Rice, MD is the president of Global Radiology CME Dr. Rice serves as the Chair of the Radiology Department of Valley Presbyterian Hospital in Los Angeles, California and is a radiologist with Renaissance Imaging Medical Associates. Dr. Rice has made several media appearances as part of his ongoing commitment to public education. Dr. Rice's passion for state of the art radiology and teaching includes acting as a guest lecturer at UCLA. In 2015, Dr. Rice and Natalie Rice founded Global Radiology CME to provide innovative radiology education at exciting international destinations, with the world's foremost authorities in their field. Follow Dr. Rice on Twitter @KevinRiceMD All posts by Kevin M. Rice, MD

SOB and Hypotension Following Coronary Artery Rotational Atherectomy • Xray of the Week This 85 year old female became short of breath, hypotensive, and lethargic shortly after rotational atherectomy of the right coronary artery. The cardiologist was concerned that there may be a retroperitoneal hemorrhage related to the femoral artery puncture, and ordered a CT abdomen and pelvis. What is the diagnosis and treatment? Figure 1A: Axial CT of lower chest. Figure 1B: Axial CT at the level of the vascular sheaths in the RLQ. Figure 1C: Coronal CT abdomen and pelvis. Figure 2A: Axial CT showing pericardial effusion (white arrows). Figure 2B: Axial CT showing no abnormality at the level of the vascular sheaths in the RLQ (white arrow). Figure 2C: Coronal CT showing pericardial effusion (white arrows). The images demonstrate no retroperitoneal abnormality. However, the CT scan demonstrates a large pericardial effusion (Figs. 1A, 1C, 2A, 2C) and, based on the clinical findings cardiac tamponade is suspected. An echocardiogram was performed which demonstrates right ventricular collapse in early diastole and right atrial inversion in late diastole in addition to the moderate sized pericardial effusion. (Fig. 3) A dilated inferior vena cava without respiratory variation was also seen, all signs of cardiac tamponade. Emergent pericardiocentesis and pericardial drainage catheter placement was performed resulting in rapid improvement in the patient's condition, no longer requiring pressors. Figure 3: Apical 4 chamber view showing right ventricular collapse in early diastole and right atrial inversion in late diastole. There is also a moderate sized pericardial effusion. Discussion Rotational atherectomy is increasingly being used for percutaneous coronary intervention due to the of the expansion of indications to more complex lesions (1,2,3). However, the compared to angioplasty, percutaneous transluminal rotational atherectomy has four times the risk for coronary artery perforation (1,3). The incidence of important procedure-related complications from rotational atherectomy is 1.3%, and the incidence of tamponade is 0.64% (4). Beck's triad consisting of jugular venous distension, distant heart sounds, and hypotension is the classic presentation of cardiac tamponade. Other symptoms of tamponade include severe respiratory distress, tachycardia, and agitation. Pulsus paradoxus, low voltage QRS complex on EKG, and a chest x-ray with enlarged cardiac silhouette may also be seen with tamponade (5). Even a small amount of pericardial fluid may cause tamponade in the acute setting, whereas a large amount of fluid accumulated over a long period of time may not cause tamponade. Treatment is pericardiocentesis and placement of a pericardial drain preferably with ultrasound guidance. Rapid treatment is often life-saving, resulting in prompt improvement in the patient's condition. Thoracotomy may be required in severe trauma. (6) Cardiac tamponade is in the differential diagnosis of pulseless electrical activity (PEA). References: 1. Wasiak J, Law J, Watson P, Spinks A. Percutaneous transluminal rotational atherectomy for coronary artery disease. Cochrane Database Syst Rev. 2012 Dec 12 2. Lee MS. Rotational Atherectomy: An Invaluable Tool for Complex Lesions. Cath Lab Digest Issue Number: Volume 19 - Issue 6 - June 2011 3. Gunning, MG, et al. Coronary artery perforation during percutaneous intervention: incidence and outcome. Heart. 2002 Nov; 88(5): 495–498. 4. Sakakura K, Inohara T, Kohsaka S, et al. Incidence and Determinants of Complications in Rotational Atherectomy. Circulation: Cardiovascular Interventions. 2016;9:e004278 5. Spodick DH. Acute Cardiac Tamponade. N Engl J Med 2003; 349:684-690 August 14, 2003 6. Shekar PS, Leacche M ,Farnam KA, et al. Surgical Management of Complications of Percutaneous Coronary Rotational Atherectomy Interventions. Ann Thorac Surg 2004;78:e81–2 Kevin M. Rice, MD is the president of Global Radiology CME Dr. Rice has served in many leadership positions; he has been the Chair of the Radiology Department and Chief of Staff of Valley Presbyterian Hospital in Los Angeles, California and is a Radiologist with Renaissance Imaging Medical Associates. Dr. Rice has made several media appearances as part of his ongoing commitment to public education. Dr. Rice's passion for state of the art radiology and teaching includes acting as a guest lecturer at UCLA. In 2015 Dr. Rice and Natalie Rice founded Global Radiology CME to provide innovative radiology education at exciting international destinations, with the world's foremost authorities in their field. In 2016, Dr. Rice was nominated and became a semifinalist for a "Minnie" Award for the Most Effective Radiology Educator. Follow Dr. Rice on Twitter @KevinRiceMD All posts by Kevin M. Rice, MD

RLQ Pain in 54 M • Xray of the Week This 54 year old male presented to the Emergency Department with right lower quadrant pain and vomiting. What is the diagnosis? Axial CT with contrast. There is a thick-walled diverticulum arising from the distal ileum with surrounding mesenteric edema, and mural enhancement diagnostic of Meckel diverticulitis. (blue arrow) Discussion Present in 2% of the population, Meckel diverticulum forms as a result of incomplete closure of the intestinal end of the omphalomesenteric duct, and is present within 40–100 cm of the ileocecal valve. The total lifetime complication rate of a Meckel diverticulum is approximately 4%. Complications include intestinal obstruction (40%) and diverticulitis (20%), torsion, intussusception, and hemorrhage. The symptoms are non specific and are most commonly attributed to appendicitis. CT scan demonstrates an inflamed diverticulum in the RLQ or midline with a normal appendix. The diverticulum may contain calcified enteroliths. Treatment is surgical excision. References: 1. Bennett GL, Birnbaum BA, Balthazar EJ. CT of Meckel's diverticulitis in 11 patients. AJR Am J Roentgenol. 2004;182 (3): 625-9. AJR Am J Roentgenol (full text) 2. Wong CS, Dupley L, Varia HN, Golka D, Linn T. Meckel's diverticulitis: a rare entity of Meckel's diverticulum. J Surg Case Rep. 2017;2017(1):rjw225. Published 2017 Jan 6. doi:10.1093/jscr/rjw225 3.Thurley PD, Halliday KE, Somers JM et-al. Radiological features of Meckel's diverticulum and its complications. Clin Radiol. 2009;64 (2): 109-18. DOI: https://doi.org/10.1016/j.crad.2008.07.012 4. Milam RA, Fonseca RB. Case 240: Meckel Diverticulitis. Radiology 2017; 283:303–307 https://pubs.rsna.org/doi/full/10.1148/radiol.2017150885 5. Elsayes KM, Menias CO, Harvin HJ et-al. Imaging manifestations of Meckel's diverticulum. AJR Am J Roentgenol. 2007;189 (1): 81-8. 6. Kotha VK, Khandelwal A, Saboo SS, et al. Radiologist's perspective for the Meckel's diverticulum and its complications. Br J Radiol. 2014;87(1037):20130743. doi:10.1259/bjr.20130743 7. Platon A, Gervaz P, Becker CD, Morel P, Poletti PA. Computed tomography of complicated Meckel's diverticulum in adults: a pictorial review. Insights Imaging. 2010;1(2):53–61. doi:10.1007/s13244-010-0017-8 Kevin M. Rice, MD is the president of Global Radiology CME Dr. Rice has served in many leadership positions; he has been the Chair of the Radiology Department and Chief of Staff of Valley Presbyterian Hospital in Los Angeles, California and is a radiologist with Renaissance Imaging Medical Associates. Dr. Rice has made several media appearances and given as part of his ongoing commitment to public education. Dr. Rice's passion for state of the art radiology and teaching includes acting as a guest lecturer at UCLA. In 2015 Dr. Rice and Natalie Rice founded Global Radiology CME to provide innovative radiology education at exciting international destinations, with the world's foremost authorities in their field. In 2016, Dr. Rice was nominated and became a semifinalist for a "Minnie" Award for the Most Effective Radiology Educator. Follow Dr. Rice on Twitter @KevinRiceMD All posts by Kevin M. Rice, MD