A rare origin of the common iliac artery

CASE REPORTS P V G s u c h as g a s t r o e n t e r i t i s , typhlitis, s t e r o i d t h e r a p y a n d p e r o x i d e e n e m a s c a n be e x c l u d e d o n clinical g r o u n d s . T h e sensitivity o f u l t r a s o u n d in d e t e c t i n g P V G in N E C has b e e n s h o w n to be g r e a t e r t h a n the a b d o m i n a l r a d i o g r a p h a n d , as d e m o n s t r a t e d by this case, m a y p r o v i d e e a r l y a n d specific e v i d e n c e o f N E C b e f o r e t h e a p p e a r a n c e o f e i t h e r r a d i o g r a p h i c o r clinical signs.

REFERENCES

5 6 7 8

1 Walsh MC, Kliegman RM, FanaroffAA. Necrotising enterocolitis: a practitioner's perspective. Paediatrics in Review 1988;9:219 226. 2 Kliegman RM, Fanaroff AA. Neonatal necrotising enterocolitis in the absence of pneumatosis intestinalis. American Journal of Diseases of Childhood 1982; 136:618-620. 3 Daneman A, Woodward S, Silva M. The radiology of neonatal necrotising enterocolitis (NEC). Paediatric Radiology 1978;7:70-77. 4 Wolfe JN, Evans WA. Gas in the portal veins of the liver in infants.

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American Journal of Roentgenology, Radium Therapy and Nuclear Medicine 1955;74:486. Malin SW, Bhutani VK, Ritchie WW et al. Echogenic intravascular and hepatic microbubbles associated with necrotising enterocolitis. Journal of Paediatries 1983;103:637-640. Merritt RB, Goldsmith JP, Sharp MJ. Sonographic detection of portal venous gas in infants with necrotising enterocolitis. American Journal of Roentgenology 1984;143:1059-1062. Lindley SL, Mollitt DL, Seibert JJ et al. Portal vein ultrasonography in the early diagnosis of necrotising enterocolitis. Journal of Paediatrie Surgery 1986;21:530-532. Robberecht EA, Afschrift M, De Bel CE et al. Sonographic demonstration of portal venous gas in necrotising enterocolitis. European Journal of Pediatrics 1988;147:192-194. Weinberg B, Peralta VE, Diakoumakis EE et al. Sonographic findings in necrotising enterocolitis with paucity of abdominal gas as the initial symptom. Mount Sinai Journal of Medicine 1989;56:330-333. Arnon RG, Fishbein JF. Portal venous gas in the pediatric age group. Journal of Pediatrics 1971;79:255-259.

Clinical Radiology (1994) 49, 651-653

Case Report: A Rare Origin of the Common Iliac Artery A. S. B R O W N ,

C. J. S O N K S E N *

a n d P. G I S H E N *

Departments o f Cardiology and *Radiology, King's College H o s p i t a l London

A rare origin of the common iliac artery is presented. The authors believe that the anomaly described has not been previously reported and suggest possible explanations. Brown, A.S., S o n k s e n , C.J. & G i s h e n , P. (1994). Clinical Radiology 49, 651 O r i g i n o f the C o m m o n Iliac A r t e r y

C o n g e n i t a l a b n o r m a l i t i e s o f the a b d o m i n a l a o r t a a r e extremely uncommon; segmental hypoplasia and coarct a t i o n o f this vessel a p p e a r to be t h e o n l y r e l a t i v e l y well d o c u m e n t e d defects [1,2,3,5]. O t h e r c o n g e n i t a l a b n o r m alities o f t h e a b d o m i n a l a o r t a b e c o m e i n c r e a s i n g l y r a r e a n d to o u r k n o w l e d g e the a n o m a l y d e s c r i b e d b e l o w has not b e e n p r e v i o u s l y r e p o r t e d . A c q u i r e d c o a r c t a t i o n , u s u a l l y r e l a t e d to a o r t i t i s o r T a k a y a s u ' s disease is m o r e f r e q u e n t l y d e s c r i b e d [4].

CASE R E P O R T A 59-year-old female, insulin-dependent diabetic who was an exsmoker, had a 20 year history of hypertension and a strong family history of ischaemic heart disease was admitted for routine day case cardiac catheterization. She gave a 6 year history of angina and had undergone cardiac catheterization 5 years previously. At that time it had been difficult to perform the procedure via the femoral route and a right brachial artery approach was therefore undertaken. The abdominal aortic anatomy was not visualized but coronary angiography showed a tight proximal left anterior descending and circumflex coronary artery stenosis for which she underwent coronary artery bypass grafting in 1987. She made a good recovery from this and remained pain-free until 1992 when she represented with a subendocardial myocardial infarct and subsequently continued to have angina. Physical examination showed her to look well, her pulse rate was 60 and regular, all peripheral pulses were present and equal, there was no radiofemoral Correspondence to: Dr C. J. Sonksen, Department of Radiology, King's College Hospital, Denmark Hill, London SE5 9RS.

653. C a s e R e p o r t : A R a r e

delay, no bruits were detected and her blood pressure was 150/90 in both arms. The heart sounds were normal with no audible murmurs and her chest was clear, Examination of her abdomen was unremarkable. She proceeded to cardiac catheterization. The femoral pulses were easily palpable and a right femoral puncture was initially performed. The catheter failed to pass beyond the level of the second lumbar vertebra and in order to define the anatomy 35 ml of Omnipaque 350 was injected (Figs 1 and 3). A left femoral artery approach was then performed and on this occasion the catheter passed easily into the upper abdominal aorta. To delineate the anatomy further a second bolus of Omnipaque 350 was injected via a pigtail catheter at the level of the renal arteries (Fig. 2). The right common iliac artery was seen to arise from the right renal artery (Fig. 1), its origin appeared narrowed with mild post-stenotic dilatation. The left renal artery was in its normal position and was shown to have a significant proximal stenosis (Fig. 2). The coeliac axis and superior mesenteric artery were seen to arise as usual just proximal to the renal arteries but the inferior mesenteric artery was not clearly demonstrated. The common iliac arteries were shown to cross each other twice in the abdomen before following their normal course (Figs 3 and 4).

DISCUSSION T h e l i t e r a t u r e d e a l i n g w i t h v a r i a t i o n s in the a n a t o m y o f t h e a b d o m i n a l a o r t a r e p o r t s cases o f c o a r c t a t i o n a n d h y p o p l a s i a o f this vessel b u t a n o m a l o u s o r i g i n o f t h e c o m m o n iliac vessels has n o t b e e n p r e v i o u s l y d e s c r i b e d . It is difficult to p o s t u l a t e t h e p o s s i b l e e m b r y o l o g y o f this v a r i a n t . N o r m a l l y , t h e c o m m o n iliac a r t e r y d e v e l o p s f r o m the u m b i l i c a l a r t e r y at t h e e n d o f

652

CLINICAL RADIOLOGY

Fig. 1 - Right femoral puncture demonstrating the right common iliac artery arising from the right renal artery.

Fig. 2 Left femoral artery puncture demonstrating the pigtail in the upper abdominal aorta and confirming that the left common iliac artery is continuous with the upper abdominal aorta.

the f o u r t h w e e k o f g e s t a t i o n . D u r i n g this p r o c e s s the umbilical artery acquires a secondary connection with a d o r s a l s e g m e n t a l b r a n c h o f the a b d o m i n a l a o r t a a n d the e a r l y v e n t r a l b r a n c h d i s a p p e a r s . T h i s n e w r e p l a c i n g s t e m b e c o m e s t h e c o m m o n iliac a r t e r y f r o m w h i c h the

LRA

SlV

Fig. 3 - Demonstration Of the double crossover of the common iliac arteries in the lower abdomen.

Fig. 4 Diagrammatic representation of the case described. CA, Coeliac axis; SMA, superior mesenteric artery; LRA, left renal artery; RRA, right renal artery; RCI, right common iliac artery; LCI, left common iliac artery.

CASE REPORTS

external iliac artery subsequently arises. The remainder of the original umbilical trunk becomes known as the internal iliac artery. It is possible that at this stage of development the secondary connection on the right side was instead made with a lateral branch of the dorsal aorta which was to persist as the right renal artery [6]. Alternatively, the defect may have occurred at an earlier stage of development with abnormal migration of the mesenchymal cells. Coarctation and segmental hypoplasia of the abdominal aorta are associated with hypertension and although a significant renal artery stenosis was demonstrated it is conceivable that the variant described also contributed to the history of hypertension in this patient. However, unless she develops significant atheroma or aneurysmal dilatation of these vessels, it is unlikely that she would need surgical correction of this abnormality.

653

Acknowledgement. The authors would like to thank Dr S. Holmberg for allowing them to report on his patient.

REFERENCES 1 QuainR. Partial contraction of the abdominal aorta. Transactions of the Pathological Society of London 1848;1:244 245. 2 Soshan MB, Rossi NP, Korns ME. Coarctation of the abdominal aorta. Archives of Pathology 1973;95:221-225. 3 Hejhal L, Hejhal J, Firt P. Coarctation of the abdominal aorta. Journal of Cardiovascular Surgery (Torino) 1973;14:168-177. 4 Funata N, Tanaka M, Hirokawa K. Coarctation of the abdominal aorta - case report with autopsy. Acta Pathologica Japonica 1981;31(1):117 127. 5 Graham L, Zelenock G, Erlandson E et aL Abdominal aortic coarctation and segmental hypoplasia. Surgery 1979;86(4):519 529. 6 Arey LB. Developmentalanatomy. A textbook andlaboratory manual of embryology, 7th ed. Philadelphia, London: WB Saunders Co, 1965:354-358.

Clinical Radiology (1994) 49, 653 654

Case Report: Gas Within a Cervical Vertebral Body N. D. GRUNSHAW and B. M. CAREY

Department of Radiology, Cookridge Hospital, Leeds We describe an unusual case of intraosseous gas within the vertebral body of C5. The differential diagnosis and likely aetioiogy is discussed. Grunshaw, N.D. & Carey, B.M. (1994). Clinical Radiology 49, 653-654. Case Report: Gas Within a Cervical Vertebral Body

CASE REPORT A 62-year-old man presented with a 3 year history of left-sided neck pain. There was nothing of relevance in his past medical history. Clinical examination demonstrated slight tenderness over the posterior aspect of the cervical spine but no other abnormality. Plain radiographs revealed extensive spondylotic change throughout the cervical spine. In addition there was a lytic defect in the body of C5 (Fig. 1). Full blood count, bone biochemistry, protein electrophoresis and chest radiographs were normal. An isotope bone scan demonstrated increased uptake throughout the lower cervical spine. A lyric metastasis was suspected and the patient was referred for computed tomography (CT) of the lower cervical spine to further elucidate the nature of the abnormality. This demonstrated a large gas collection (-700 HU) within the vertebral body of C5 (Fig. 2). There was no evidence of any associated soft tissue mass and although the adjacent intervertebral discs were degenerate, no gas was demonstrated within either of these discs. A diagnosis of degenerate intraosseous gas was made and the patient was subsequently managed conservatively. He remains well 2 years later.

DISCUSSION The presence of gas within intervertebral discs is a well recognized radiological phenomenon [1] occurring in up to 20% of spinal radiographs in association with a variety of conditions including disc degeneration, trauma, metastatic disease and infection [2,3]. Intravertebral gas, however, is unusual. It has most commonly been described in association with osteoCorrespondence to: Dr N.D. Grunshaw, Department of Radiology, Cookridge Hospital, Leeds LS16 6QB.

necrosis [4]; in these cases the gas collections are usually linear, commonly occurring around the thoracolumbar junction and always associated with significant vertebral collapse [5]. There may be predisposing factors such as concomitant steroid therapy or diabetes mellitis. Trauma and repeated microtrauma have also been associated with intravertebral vacuum phenomenon [5]. It has been suggested that the phenomenon represents an ununited vertebral fracture with possible formation of a pseudoarthrosis. The gas collects in cracks caused by negative pressure, particularly during distraction during spinal extension, and views in this position may be helpful for its optimum demonstration. Degenerative disc disease may be associated with gas within intervertebral discs and this gas may extend into the adjacent subchondral bone, in association with intravertebral disc herniation through vertebral end plates (Schmorls nodes) [3,6]. In these cases the gas collections are more likely to be rounded [3,5,7]. Occasionally, intravertebral gas is associated with neoplastic or myelomatous involvement of vertebrae [5,8], although this is unusual. It has generally been stated that the presence of intraosseous vertebral gas makes infection unlikely [6], although it has occasionally been reported in association with vertebral osteomyelitis [9]. In these cases the gas may appear as multiple small locules presumably produced under high pressure by the infecting organisms. Most of the previous cases of intraosseous vertebral gas