occlusion of the internal carotid artery proximal to or on either side of the aneurysm (trapping), following trial occlusion and assessment of the collateral circulation, to be the treatment of choice. Trapping decreases the risk of subsequent thromboembolic events as compared with proximal balloon only or surgical occlusion but does carry the risk of dislodging clot whilst traversing the aneurysm . In conclusion, the presentation of petrous carotid aneurysms is non-specific but they should be considered in patients with destructive skull based lesions involving the petrous bone to avoid inadvertent biopsy and possible fatality. Acknowledgement. We wish to thank Mr C. B. T. Adams for referring this patient for endovascular treatment. REFERENCES 1 Costantino PD, Russell E, Reisch D et al. Ruptured petrous carotid aneurysm presenting with otorrhagia and epistaxis. The American Journal of Otology 1991;12:378-383.
2 Rawlinson J, Colquhoun IR. Aneurysms involving the intrapetrous internal carotid artery: a rare cause of Horner's syndrome. British Journal o f Radiology 1990;63:69-72. 3 Leonetti JP, Smith PG, Linthicum FH. The petrous carotid artery: anatomic relationships in skull base surgery. Otolaryngology and Head and Neck Surgery 1990;102:3-12. 4 Halbach W , Higashida RT, Hieshima GB et al. Aneurysms of the petrous portion of the internal carotid artery: results of treatment with endovascular or surgical occlusion. American Journal of Neuroradiology 1990;11:253 257. 5 Kudo S, Colley DP. Multiple intrapetrous aneurysms of the internal carotid artery. American Journal of Neuroradiology. 1983;4:11191121. 6 Guirguis S, Tadros FW. An internal carotid aneurysm in the petrous temporal bone. Journal of' Neurology, Neurosurgery and Psychiatry 1961;24:84 85. 7 Hiranandani LH, Chandra O, Malpani N e t al. An internal carotid aneurysm in the petrous temporal bone. Journal o f Laryngology and Otology 1962;76:703 706. 8 Anderson RD, Liebeskind A, Schechter MM et al. Aneurysms of the internal carotid artery in the carotid canal of the petrous temporal bone. Radiology 1972;192:639-642. 9 Glasscock ME, Smith PG, Band AG et al. Management of aneurysms of the petrous portion of the internal carotid artery by resection and primary anastamoses. Laryngoscope 1983;93:1445 1453.
Clinical Radiology (1996) 51, 660 662
Case Report: Extensive Calcified Thrombus of the Inferior Vena Cava R. G. McWILLIAMS, P. J. O ' C O N N O R and A. G. C H A L M E R S
Department of Radiology, Leeds General Infirmary, Leeds, UK .f
We report a case of extensive abdominal and pelvic venous calcification in an adult who thirty years previously had a probable left femoral vein thrombosis. It is thought that calcified thrombus occurring in the paediatric population typically undergoes spontaneous resolution. Hence there are a few documented cases of calcified caval thrombus in the adult population. We postulate that in this case, calcified thrombus has been present since a thrombotic episode some thirty years previously.
CASE R E P O R T An 83-year-old male was admitted for investigation of haematuria and chronic renal failure. He was currently being treated for gout and had previously had a cardiac pacemaker inserted via the left subclavian vein. His past medical history included the removal of a blood clot from his left groin thirty years previously. A detailed surgical record from that episode was not available for review. We presume the episode was due to a femoral vein thrombosis. A plain abdominal radiograph showed extensive vascular calcification (Fig. 1). Abdominal ultrasound showed multiple cysts in both kidneys but no other abnormality. Cystoscopy was normal. Abdominal CT confirmed the presence of cysts in both kidneys but also revealed extensive calcification involving the femoral vein, iliac veins and inferior vena cava (IVC) (Fig. 2a c). A normal IVC was not identified but calcification continued in the expected position of a markedly atrophic cava up to the level of the renal vascular pedicle. The cava Correspondence to: Dr A. G. Chalmers, CT/MR Unit, Clarendon Wing, Leeds General Infirmary, Leeds LSI 3EX, UK.
Fig. 1 Plain abdominal radiograph demonstrates extensive calcification in the iliac veins and IVC. © 1996 The Royal Collegeof Radiologists, ClinicalRadiology, 51, 660-662.
was not identified proximal to this. In addition, a leash of collateral vessels were noted within the subcutaneous fat of the right buttock as well as further collateral vessels seen within the anterior abdominal wall (Fig. 2b).
Calcified thrombus in the inferior vena cava (CTIVC) is a rare radiological finding. Most reports describe a characteristic pattern of calcification typically seen on a child's plain abdominal radiograph. The classical finding is that of a bullet shaped focus of calcification to the right of the thoracolumbar junction in the expected position of the suprarenal portion of the IVC . There have been few case reports of CTIVC in adults [2--5] and this has led to a hypothesis that calcified thrombus seen in the paediatric population may spontaneously resolve [6-8]. Calcified thrombus in the iliac veins has been reported although no extension into the IVC was demonstrated in this case . Although CTIVC is usually an incidental finding and the plain film appearances are often characteristic, not all patients have this typical pattern. Atypical or incompletely developed calcification may require ultrasound  or CT  to confirm the diagnosis. It is generally agreed that once diagnosed, no further investigation or treatment is necessary [1,8,11]. There has been one report of renal failure secondary to renal vein thrombosis developing on a background of CTIVC . In another case, embolization from CTIVC was suspected as a cause of cerebral infarction in a child with transposition of the great vessels . We report a case showing extensive femoral, iliac, and IVC calcified thrombus, diagnosed by CT in an elderly male with chronic renal failure who had a past history consistent with femoral vein thrombosis some thirty years previously. We are aware of only one previously reported case documenting extensive iliac and IVC calcified thrombus . This report adds to the small number of documented cases of CTIVC in adults. While noting the hypothesis of spontaneous resolution of CTIVC in children, we would postulate that in this case, the calcified thrombus has been present since the original thrombotic episode some thirty years previously.
(c) Fig. 2 - Contrast-enhanced CT images showing dense calcification (arrows) in (a) the iliac veins and (b) inferior vena cava. Note the collateral vessels in the right buttock and anterior abdominal wall (arrowheads). (c) Multiplanar reconstruction in the coronal plane shows calcified t h r o m b u s of the iliac veins and inferior vena cava. © 1996 The Royal College of Radiologists, ClinicalRadiology, 51, 660 662.
1 Kirks D R , Ponzi JW, Korobkin M. Computed Tomographic diagnosis of calcified inferior vena cava thrombus in a child with Wilms' tumour. Pediatric Radiology 1980; 10:110 112. 2 Gammill SL, Nice CM. Calcification in the inferior vena cava. Radiology 1969;92:1288-1290. 3 Feldberg M A , Staverman HJ. CT demonstration of calcified postthrombotic inferior vena cava. Diagnostic Imaging in Clinical Medicine 1986;55:164-167. 4 Hill JD, Hetzer R. Surgery of tumors of the subdiaphragmafic inferior vena cava. Journal of Thoracic and Cardiovascular Surgery 1978;76:38 42. 5 Cagnoli L, Viglietta G, Madia G e t al. Acute bilateral renal vein thrombosis superimposed on calcified thrombus of the inferior vena cava in a patient with m e m b r a n o u s lupus nephritis. Nephrology, Dialysis, Transplantation, 1990;5 suppl. 1:71-74. 6 D u Lac P, Panuel M, Devred P e t al. T h r o m b u s calcifi~ de la veine cave inf~rieure. Journal de Radiologie 1987;68:719 725. 7 Kassner EG, Baumstark A, Kinkhabwala M N et al. Calcified thrombus in the inferior vena cava in infants and children. Pediatric Radiology 1976;4:167-171.
8 Paill6 P, Quesnel Ch, Bouchet JJ et al. T h r o m b u s calcifi6 de la veine cave inf~rieure. Annales de Radiologie 1989;32:151 154. 9 Banker VP. Calcified external iliac v e i n thrombosis. Radiology 1975;l 17:311-314. 10 Sandler M A , Beute GH, Madrazo BL et al. Ultrasound case of the day. Radiographics 1986;6:512-514. 11 Cunat JS, Morrison SC, Fletcher BD. Sonographic diagnosis of
calcified thrombus of the inferior vena cava. British Journal of
Radiology 1982;55:160-162. 12 Velasquez G, D'Souza VJ, Glass T A et al. Calcified thrombus of the inferior vena cava in transposition of the great vessels. Cardio. vascular and Interventional Radiology 1986;9:19-21. 13 G o o d m a n GA. Intraluminal iliac venous calcification. British Journal o f Radiology 1975;48:457 459.
Clinical Radiology (1996) 51,662 664
Case Report: Hepatic Adenoma With Nodule-in-nodule Appearance: CT and MR Findings M. M A T S U I , K. I T O and T. N A K A N I S H I
Department of Radiology, Yamaguchi University School of Medicine, Yamaguchi, Japan Hepatic adenoma is a rare benign tumour of the liver, and there are some reports of radiological findings in this turnout [1-4]. In these reports, the computed tomography (CT) and magnetic resonance (MR) appearances of hepatic adenomas were described as highly variable due to their varied histology, such as intratumoural haemorrhage, necrosis, and fatty change. We recently experienced a case of a hepatic adenoma with a 'nodule-innodule' appearance; such CT and M R findings have not been previously described. We therefore report an unusual case of a hepatic adenoma in which a 'nodulein-nodule' appearance was demonstrated on CT and M R images.
after beginning a bolus injection with a power injector of 100ml contrast agent (Iopamidol 300mgI/ml) at the rate of 4ml/s with a 1 s scan time and 2 s table incrementation. Twelve consecutive images were obtained during a single breath-hold. On incremental CT, the mass showed a 'nodule-in-nodule' appearance with small nodules showing rapid enhancement noted within this mass (Fig. 1). On delayed CT,
CASE R E P O R T A 21-year-old w o m a n had a five year history of painless epigastric mass. She had no history of oral contraceptive use. CT was performed using a Toshiba TCT-900S scanner (Tokyo, Japan). Pre-contrast CT revealed a slightly hypodense mass measuring 16.5 x 8.5 cm in diameter in the left hepatic lobe. Subsequently, table incremental dynamic CT (incremental CT) was performed. Incremental CT was initiated 20 s
Fig. 1 - Incremental dynamic CT image. A huge mass is demonstrated in the left hepatic lobe. Small nodules with rapid enhancement are noted within the mass (arrows). Correspondence to: Dr Katsuyoshi Ito, Yamaguchi University School of Medicine, Department of Radiology, 1144 Kogushi, Ube, Yamaguchi, 755 Japan.
(b) Fig. 2. - (a) Tl-weighted (600/15) M R image. The mass is demonstrated as an iso-intensity area. Small nodules with low intensity rims are noted within the mass (arrows). (b) T2-weighted (2000/90) M R image. Small nodules with high intensity rims are noted within the mass (arrows). © 1996 The Royal College of Radiologists, ClinicalRadiology, 51, 662-664.