Papel de la PET/TC con 18F-DOPA en el diagnóstico de la forma congénita focal del hiperinsulinismo en niños / The role of 18F-DOPA PET/CT in the diagnosis of the congenital focal form of hyperinsulinism in children

ANTECEDENTES: El hiperinsulinismo congénito (HIC) es una enfermedad neuroendocrina con anomalías focales o difusas en el páncreas. Mientras que las formas difusas resistentes a los medicamentos requieren una pancreatectomía casi total o una farmacoterapia prolongada, el HIC focal podría ser tratado por resección quirúrgica dirigida. Por tanto, evaluamos la utilidad del 18F-DOPA PET/TC para identificar la forma pancreática focal. Objetivos y metodología: Diecinueve niños (11 niños y 8 niñas de 2 a 54meses de edad) con signos clínicos de HIC neonatal y exámenes genéticos positivos fueron registrados en el estudio. Después de la administración intravenosa del 18F-DOPA, una primera PET y posteriormente otra PET/TC cubriendo longitudinalmente la región toracoabdominal fueron llevadas a cabo. Ambas adquisiciones fueron realizadas en modo dinámico para permitir la exclusión de imágenes con artefactos de movimiento. Los valores de absorción estandarizados fueron ajustados al peso corporal (SUVbw). El hallazgo fue considerado como focal cuando la proporción de SUVbwmax entre la región sospechosa y el resto del páncreas fue mayor que 1,2. RESULTADOS: Las formas focales fueron registradas en 10/19 niños y 4 de ellos se sometieron a una resección quirúrgica con recuperación completa. La captación focal fue significativamente mayor que la captación en el tejido pancreático normal (p = 0,0059). Las formas focales y difusas del HIC no difieren significativamente en la captación del tejido pancreático normal. No encontramos ninguna ventaja en la medición de la relación SUVbwmean en comparación con la relación SUVbwmax (p = 0,50). CONCLUSIONES: 18F-DOPA PET/TC es una herramienta útil para la localización de HIC focal y la planificación de un tratamiento quirúrgico

BACKGROUND: Congenital hyperinsulinism (CHI) is a neuroendocrine disease with focal or diffuse abnormalities in pancreas. While drug-resistant diffuse forms require near-total pancreatectomy or prolonged pharmacotherapy, focal CHI may be treated by targeted surgical resection. We evaluated the usefulness of 18F-DOPA PET/CT to identify the focal pancreatic form. Subjects and methods: Nineteen children (11 boys, 8 girls, aged 2-54 months) with clinical signs of neonatal CHI and positive genetic examinations were enrolled in the study. After i.v. administration of 18F-DOPA, early PET and late PET/CT acquisition covering one-bed length over thoraco-abdominal region were performed. Both acquisitions were done in dynamic mode to allow exclusion of frames with motion artefacts. Standardized uptake values were adjusted to bodyweight (SUVbw). The finding was considered as focal when the ratio of SUVbwmax between the suspicious region and the rest of pancreas was greater than 1.2. RESULTS: Focal forms were recorded in 10/19 children and 4 of them underwent surgical resection with complete recovery. Focal uptake was significantly higher than the uptake in the normal pancreatic tissue (p = 0.0059). Focal and diffuse forms of CHI did not differ significantly in normal pancreatic tissue uptake. We found no advantage in the measurement of SUVbwmean ratio compared to SUVbwmax ratio (p = 0.50). CONCLUSION: 18F-DOPA PET/CT is a useful tool for the localization of focal CHI and planning of surgical treatment

The role of 18F-DOPA PET/CT in the diagnosis of the congenital focal form of hyperinsulinism in children. / Papel de la PET/TC con 18F-DOPA en el diagnóstico de la forma congénita focal del hiperinsulinismo en niños.

BACKGROUND: Congenital hyperinsulinism (CHI) is a neuroendocrine disease with focal or diffuse abnormalities in pancreas. While drug-resistant diffuse forms require near-total pancreatectomy or prolonged pharmacotherapy, focal CHI may be treated by targeted surgical resection. We evaluated the usefulness of 18F-DOPA PET/CT to identify the focal pancreatic form. SUBJECTS AND METHODS: Nineteen children (11 boys, 8 girls, aged 2-54 months) with clinical signs of neonatal CHI and positive genetic examinations were enrolled in the study. After i.v. administration of 18F-DOPA, early PET and late PET/CT acquisition covering one-bed length over thoraco-abdominal region were performed. Both acquisitions were done in dynamic mode to allow exclusion of frames with motion artefacts. Standardized uptake values were adjusted to bodyweight (SUVbw). The finding was considered as focal when the ratio of SUVbwmax between the suspicious region and the rest of pancreas was greater than 1.2. RESULTS: Focal forms were recorded in 10/19 children and 4 of them underwent surgical resection with complete recovery. Focal uptake was significantly higher than the uptake in the normal pancreatic tissue (p=0.0059). Focal and diffuse forms of CHI did not differ significantly in normal pancreatic tissue uptake. We found no advantage in the measurement of SUVbwmean ratio compared to SUVbwmax ratio (p=0.50). CONCLUSION: 18F-DOPA PET/CT is a useful tool for the localization of focal CHI and planning of surgical treatment.

The role of 99mTc-MIBI SPECT/low dose CT with 3D subtraction in patients with secondary hyperparathyroidism due to chronic kidney disease.

OBJECTIVE: The aim of the present work was to assess the incidence of parathyroid glands hyperplasia or adenoma in patients with various stages of chronic renal insufficiency using 99mTc-methoxyisobutylisonitrile (MIBI) SPECT and 3D subtraction technique with 99mTc-pertechnetate (Tc). SUBJECTS AND METHODS: Sixty one patients underwent hybrid SPECT with low-dose CT of the parathyroid glands and thyroid SPECT scintigraphy. Thirty six patients were with chronic kidney disease (CKD) without renal failure (RF) and 25 patients underwent peritoneal dialysis or hemodialysis. In each patient, two SPECT studies were performed - an early and a late one with low dose of CT with MIBI injection. Additional SPECT was performed on another day with Tc. SPECT studies were evaluated visually using volume rendering method and semi-quantitatively by 3D subtraction of Tc SPECT from early MIBI SPECT. RESULTS: From all 61 patients, 40/61 (66%) findings were positive, 7/61 (12%) inconclusive, and 14/61 (23%) negative. Solitary lesions were detected in 22 patients. More than one lesion was found in 18 patients. CONCLUSION: The incidence of secondary hyperparathyroidism was detected in 40/61 patients (66%) with chronic kidney disease using scintigraphy and 16 patients (40%) from them underwent surgery. MIBI SPECT/low dose CT with 3D dual - tracer subtraction (MIBI-Tc) method is an effective tool for preoperative detection of the parathyroid glands hyperplasia or adenoma.

[Correlation of 99mTc-dTPA renal scintigraphy with ACE inhibitor and ultrasound findings in screening for renal artery stenosis]. / Korelace nálezu dynamické scintigrafie ledvin pomocí 99mTc-dTPA s ACE inhibitorem a sonografického vysetrení pri skríninku stenózy renální arterie.

BACKGROUND: ACE inhibitor renal scintigraphy is widely accepted as a useful test in screening of unilateral renal artery stenosis. Another screening examination is ultrasonography, which detects haemodynamic changes with evaluation of resistive index (RI). The aim of the present study was correlation of 99mTc-DTPA captopril renography and duplex ultrasound findings in diagnosis of renal artery stenosis before angiography, that is used as "gold standard". Angiography was performed in 35 patients and their findings were correlated with scintigraphy and ultrasonography. METHODS AND RESULTS: 93 patients (49 male and 44 female) aged 27 to 84 years were examined. Ultrasonography was performed in all patients with evaluation of RI. Estimation of scintigraphy was performed in accordance with interpretative criteria of 99mTc-DTPA captopril renography, which were established at the 9th Symposium of radionuclides in nefro-urology (Santa Fé 1995) and Guideline for diagnosis of renovascular hypertension (1998). 1) Agreement positive and negative findings on scintigraphy and ultrasonography were in 61/93 patients (66%). 2) Within the group of 35 patients with angiography, the correlation between scintigraphy and ultrasonography findings was found in 27 patients (77%). 3) When scintigraphy and angiography were correlated, the correctly diagnosed renal artery stenosis was found in 27 patients with sensitivity (77%). 4) When sonography and angiography were correlated, the correctly sonographicaly diagnosed renal artery stenosis was found in 26 patients with sensitivity (74%). CONCLUSIONS: On the basis of our results and according to our experience with both examinations we can conclude, that screening of unilateral renal artery stenosis with using these nonivasive methods can help to select better the indicated patients for angiography.

[Evaluation of Stages of Legg-Calvé-Perthes Disease Using Conway's Scintigraphic Classification.]. / Vyuzití scintigrafické klasifikace podle Conwaye pri hodnocení stadií morbus Legg-Calvé-Perthes.

Legg-Calvé-Perthes disease (LCPD) is considered as avascular necrosis of the proximal femoral epiphysis, that can result in a secondary osteoarthritis. Bone scintigraphy using 99mTc phosphonate complexes is a suitable method for study of changes of LCPD. The authors present a group of 59 children (44 boys, 15 girls), with clinical suspicion of LCPD or with clear diagnosis of LCPD according to X-ray examination, who were examined using scintigraphy. The patological scintigraphic images of the proximal femoral epiphysis are evaluated according to Conway's classification. The correlation of pinhole imaging of the hip X-ray examination is neccessery for the correct diagnosis of stage of LCPD according to Conway's criteria. In author's experience Conway's classification is useful for evaluation of the development of disease; this is important for prognosis and treatment of LCPD. Key words: Legg-Calvé-Perthes disease, bone scintigraphy, scintigraphic classification.