Pediatric Radiology

Pediatr Radiol (1984) 14:443-444

9 Springer-Verlag 1984

Scintigraphic imaging of renal angioma H. Creutzig and H.-P. Krohn Department of Radiology and Children's Hospital Medical School of Hannover, Hannover, FRG

Abstract. Renal angiomyolipomas are frequent findings in patients with tuberous sclerosis. They must be localized before a biopsy is done. Radionuclide blood pool scintigraphy is a simple noninvasive procedure for the localization of hemangiomatous tumours. A patient is presented with four renal angiomas shown by this technique.

In 40 to 80% of all patients with tuberous sclerosis (TS) there are renal tumors containing various degrees of fatty, muscular, and vascular components [4]. These angiomyolipomas are usually multiple, bilateral, and asymptomatic. Because of the danger of hemorrhage renal biopsy is not recommended [1]. Cystic renal lesions, however, may be the first and only visible manifestation of TS in young children; a renal biopsy is warranted in all children presenting with multiple renal cysts and without a familiary history of polycystic kidneys to exclude the diagnosis of TS [7]. Chronic renal failure will be a rare complication in these patients and a renal biopsy may be necessary to exclude other renal diseases [6]. The exclusion of renal angiomyolipomas must be done prior to biopsy to avoid a subsequent hemorrhage. Angiography has been proposed as method of choice [5], but it is an invasive study and not without risk for the patient. We demonstrate the usefulness of the scintigraphic "blood pool scan" for the diagnosis of renal angiomas.

Case report In an 11-year-old girl the diagnosis of TS was confirmed by family history, skin lesions and CT findings. Henoch-Schoenlein disease together with a progressive renal failure was diagnosed in another

hospital. In the Children's Hospital a renal biopsy was considered. Sonographically no renal abnormalities were seen. The technique of radionuclide blood pool scintigraphy for the detection of hemangiomas has been discussed in detail elsewhere [3]. Briefly, 2 ml blood were withdrawn, the erythrocytes separated, incubated with Sn2+ and Technetium-99m, washed and reinjected. More than 95% of the activity will stay in the vascular compartment for about 5 h. The procedure is widely used in nuclear cardiology. The patient received 0.1 mCi Tc-99m/kg body weight in a small volume (0.5 ml suspended erythrocytes). The first transit through the kidneys was imaged and no hypervascularisation was seen. Two hours later the patient was reimaged both in the upright and supine position (Fig. 1). In the supine position four foci of increased uptake were seen and interpreted as angiomatous tumors within both kidneys.

Discussion

Radionuclide blood pool imaging is a simple, noninvasive and inexpensive technique for the localization of hemangiomatous tumors [3]. Hypervascularity can be demonstrated by a bolus injection when imaging the first transit (radionuclide angiography). On study of the first transit an increased blood flow (and not blood volume) may be inferred. The regional blood volume can be measured after complete mixing of the labelled erythrocytes in the intravascular spaces. Because of decreased flow in partially thrombosed hemangiomas in a third of patients the lesion was seen only in the delayed scans [2]. Artefacts can occur with an inadequate labelling technique (uptake in the thyroid, salivary glands, stomach or excretion via the kidneys) or following degradation of cells during the labelling procedure (uptake in the spleen). Therefore proper labelling techniques must be used. The radiation exposure is in the same range as that of a plain abdominal X-ray and so this method is particularly suitable in pediatric patients.

444

H. Creutzig and H.-R Krohn: ScintJgraphic imaging of renal angioma

Fig. 1 a-c. Scintigraphy from dorsal two hours after application of 2.7 mCi Tc-99m-labelled erythrocytes, a General purpose collimator, supine position, b High resolution collimator, upright position, c High resolution collimator: four angiomas shown supine position, 1 Mcts each image

For the localization of small foci, especially in young children, proper imaging techniques must be used. In our patient all foci could be seen only with a high resolution collimator and in the supine position (Fig. 1).

References 1. Chonko AM, Weiss SM, Stein JH, Fen-is TF (1974): Renal involvement in tuberous sclerosis. Am J Med 56:124-132 2. Creutzig H, Brflsch ChE, Gratz KF, Neuhaus P, MOiler St, Schober O, Lang W, Hundeshagen H und Pichlmayr R (1984): Nuklearmedizinische Differentialdiagnostik intrahepatischer Raumforderungen. Dtsch med Wschr (im Druck) 3. Front D, Royal HD, Israel O, Parker JA, Kolodny G M (198I):

Scintigraphy of hepatic hemangiomas: The value of Tc-99mlabeled red blood cells. J Nucl Med 22:684-687 4. Gomez M R (1979): Tuberous Sclerosis, New York, Raven Press 5. Jones JC, Montoya SF, Johnson JW (1980): Tuberous sclerosis presenting as chronic renal failure. South Med J 73: 551-554 6. Okada RD, Platt MA, Fleishman J (1982): Chronic renal failure in patients with tuberous sclerosis association with renal cysts. Nephron 30:85-88 7. Stapleton FB, Johnson D, Kaplan GW, Griswold W (1980): The cystic renal lesion in tuberous sclerosis. J Pediatr 97:574-579 Date of final acceptance: 17 June 1983 Dr. H. Creutzig Abteilung Nuklearmedizin Medizinische Hochschule D-3000 Hannover 61 FRG

Literature in pediatric radiology (continued from p. 440) Monatsschrift Kiaderheilkunde (Berlin) Das Syndrom der supravalvul~iren Aortenstenose (Williams-Beuren-Syndrom) in Verbindung mit Ver~inderungen der Niere und ableitenden Hamwege. Stoermer, J. et al. (Kinderkardiol.-Abt., Univ.-Kinderklin., Hufelandstr. 55, D-4300 Essen 1, FRG) t32, 110 (1984) Faltenbildungen im proximalen Ureter. Mtiller-Wiefel, D.E. et al. (Univ.-Kinderklin., Im Neuenheimer Feld 150, D-6900 Heidelberg, FRG) 132, 153 (1984) Die lumbale Radioisotopen-Zistemographie bei Frtihgeborenen. Roloff, D. W. et al. (Univ. of Michigan Med. Sch., Ann Arbor, MI, USA) 132,189 (1984) Neuropediatrics (Stuttgart) Cerebellar atrophy following diphenylhydantoin intoxication. Baler, W. K. et al. (Abt. L Neurop/id. im Klinikum der Christian.-Albrechts-Univ. Kiel, Kinderklin., Schwanenweg 20, D-2300 Kiel, FRG) 15, 76 (1984) Cerebral calcifications and cerebellar hypnplasia in two children: Clinical, radiological and neuropathological studies. A separate neurodevelopmental entity. Troost, D., Van Possum, A. (Dr. Willemse, Dept. of Childneurol. Univ. Hosp., Catharijnsinge1101, 3511 GV Utrecht, Netherlands) 15, 102 (1984)

Sonographic demonstration of contusional white matter clefts in an infant. Hausdorf G., Helmke, K. (Dept. of Ped., Univ. of Hamburg, Martinistr. 52, D-2000 Hamburg 20, FRG) 15, 110 (1984)

Neuroradiology (Berlin) Ultrasound in follow-up of the postoperative brain. Olislagers-De Slegte, R.G.M. et al. (Dept. of Neurorad., Acad. Ziekenhuis, Vrije Univ., Amsterdam, Netherlands) 26, 267 (1984) Computed tomographic findings in septo-optic dysplasia: Discordance between clinical and radiological findings. Wilson, D. M. et al. (S-322 Dept. of Ped., Stanford Univ. Med. Centel, Stanford, CA 94305, USA) 26, 279 (1984) A rare cause of spinal cord compression in childhood from intraspinal mesenchymal chondrosarcoma. A report of two cases and review of the literature. Chan, H. S. L. et al. (Dept. of Ped., Hosp. for Sick Children, 555 Univ. Ave., Toronto, Ontario M5G 1X8, Canada) 26, 323 (1984) Computed tomographic brain scan findings in Q fever encephalitis. Gomez-Aranda, F. et al. (Los Pinos de Montequinto, torre2, 8~ Sevilla, SPain) 26, 329 (1984) (continued on p. 448)