[SPECT-CT 67Ga studies in lymphoma disease. Contribution to staging and follow-up]. / Estudios SPECT-TAC con Ga de la enfermedad linfomatosa. Su aportación en la estadificación y seguimiento de la enfermedad.

INTRODUCTION: 67Ga scintigraphy is an established method for the staging and follow-up of patients diagnosed of lymphomas. The aim of this study is to evaluate advantages of 67Ga SPECT-CT study over planar, SPECT and high resolution CT studies in lymphoma disease. MATERIAL AND METHODS: One hundred and one 67Ga studies corresponding to 74 patients (46 men) were obtained, mean age 44 years. Thirty-eight patients (51 %) were diagnosed of Hodgkin's lymphoma and 36 were non-Hodgkin's lymphoma. All patients were evaluated with 67Ga and high-resolution CT studies. 67Ga studies were performed in a hybrid system, obtaining planar, SPECT and fused SPECT-CT imaging. Findings obtained from 67Ga studies were correlated with findings obtained from CT studies, both much in number of tumoral lesions and in their localization. RESULTS: Planar, SPECT, SPECT-CT and CT studies detected 123, 146, 155 and 132 lesions respectively. SPECT-CT and CT were concordant in 52 studies, while there was no concordance between SPECT-CT and CT in the remaining 49 studies, SPECT-CT detecting more lesions than CT in 28 of them. These findings changed the disease stage 18 times (18 % of whole studies). CONCLUSION: These results show better efficiency of 67Ga SPECT-CT compared to the other acquisition methods of 67Ga study and to CT for detection of tumoral lymphomatous lesions. 67Ga SPECT-CT study improves the diagnostic yield of the study with 67Ga in patients with lymphoma, providing better anatomical localization of tumoral lesions and detection of extraganglionar disease.

Estudios SPECT-TAC con 67Ga de la enfermedad linfomatosa. Su aportación en la estadificación y seguimiento de la enfermedad / SPECT-CT 67Ga studies in lymphoma disease. Contribution to staging and follow-up

Introducción. La gammagrafía con 67Ga es un método establecido en la estadificación y seguimiento de los pacientes diagnosticados de linfoma. El objetivo de este estudio es valorar las ventajas de la gammagrafía con 67Ga y SPECT-TAC sobre los estudios planares y SPECT y sobre la TAC de alta resolución en la enfermedad linfomatosa. Material y métodos. Se analizaron 101 estudios con 67Ga pertenecientes a 74 pacientes (46 hombres), edad media 44 años. Treinta y ocho pacientes (51 %) estaban diagnosticados de linfoma de Hodgkin y 36 no hodgkinianos. Todos los pacientes fueron evaluados mediante estudio con 67Ga y TAC de alta resolución. La exploración con 67Ga se realizó en un sistema híbrido, obteniendo imágenes planares, SPECT y fusión SPECT-TAC. Los resultados obtenidos de los estudios con 67Ga se compararon con los de la TAC, tanto en número de lesiones como en su localización. Resultados. Los estudios planares, SPECT, SPECT-TAC y TAC detectaron 123, 146, 155 y 132 lesiones, respectivamente. La SPECT-TAC y la TAC fueron coincidentes en 52 estudios, mientras que en los otros 49 estudios no hubo concordancia en número de lesiones, detectando la SPECT-TAC más lesiones que la TAC en 28 de ellos, modificando la estadificación de la enfermedad en 18 ocasiones (18 % de los estudios). Conclusiones. Estos resultados muestran una mayor efectividad del estudio de 67Ga y fusión SPECT-TAC en comparación con los otros métodos de adquisición gammagráficos y con la TAC de alta resolución en la detección de lesiones linfomatosas. Este método mejora el rendimiento diagnóstico de los estudios con 67Ga, aportando una mejor localización anatómica de las lesiones y permitiendo detectar lesiones extraganglionares

Introduction. 67Ga scintigraphy is an established method for the staging and follow-up of patients diagnosed of lymphomas. The aim of this study is to evaluate advantages of 67Ga SPECT-CT study over planar, SPECT and high resolution CT studies in lymphoma disease. Material and methods. One hundred and one 67Ga studies corresponding to 74 patients (46 men) were obtained, mean age 44 years. Thirty-eight patients (51 %) were diagnosed of Hodgkin's lymphoma and 36 were non-Hodgkin's lymphoma. All patients were evaluated with 67Ga and high-resolution CT studies. 67Ga studies were performed in a hybrid system, obtaining planar, SPECT and fused SPECT-CT imaging. Findings obtained from 67Ga studies were correlated with findings obtained from CT studies, both much in number of tumoral lesions and in their localization. Results. Planar, SPECT, SPECT-CT and CT studies detected 123, 146, 155 and 132 lesions respectively. SPECT-CT and CT were concordant in 52 studies, while there was no concordance between SPECT-CT and CT in the remaining 49 studies, SPECT-CT detecting more lesions than CT in 28 of them. These findings changed the disease stage 18 times (18 % of whole studies). Conclusion. These results show better efficiency of 67Ga SPECT-CT compared to the other acquisition methods of 67Ga study and to CT for detection of tumoral lymphomatous lesions. 67Ga SPECT-CT study improves the diagnostic yield of the study with 67Ga in patients with lymphoma, providing better anatomical localization of tumoral lesions and detection of extraganglionar disease

[123I-MIBG SPECT-CT combined with gamma probe for radioguided localization of pheochromocytoma]. / SPECT-TC con 123I-MIBG y sonda gamma portátil en la localización radioguiada de un feocromocitoma.

We report a case of a 56-year-old male with high suspicion of an intraabdominal catecholamine-producer tumor. The patient underwent different diagnostic procedures including 123I-meta-iodobenzylguanidine (123I-MIBG) scintigraphy, with subsequent SPECT and low resolution CT for attenuation correction and anatomic and functional image fusion. After practicing a new 123I-MIBG scintigraphy the patient was taken to the operating room, where a hand-held gamma probe detector helped to localize the lesion.

SPECT-TC con 123I-MIBG y sonda gamma portátil en la localización radioguiada de un feocromocitoma / 123I-MIBG SPECT-CT combined with gamma probe for radioguided localization of pheochromocytoma

Presentamos el caso de un hombre de 56 años con elevada sospecha de tumoración intraabdominal productora de catecolaminas. El paciente fue sometido a diversas pruebas diagnósticas, entre las que se incluyó un rastreo gammagráfico con 123I-metayodobencilguanidina (123I-MIBG), complementado con SPECT y TC de baja resolución para corrección de atenuación y posterior fusión de las imágenes anatómicas y funcionales. Después de un nuevo rastreo con 123I-MIBG el paciente fue intervenido quirúrgicamente con el apoyo intraoperatorio de una sonda gamma portátil, que facilitó la localización de la tumoración

We report a case of a 56-year-old male with high suspicion of an intraabdominal catecholamine-producer tumor. The patient underwent different diagnostic procedures including 123I-meta-iodobenzylguanidine (123I-MIBG) scintigraphy, with subsequent SPECT and low resolution CT for attenuation correction and anatomic and functional image fusion. After practicing a new 123I-MIBG scintigraphy the patient was taken to the operating room, where a hand-held gamma probe detector helped to localize the lesion

[Tumor redifferentiation in papillary thyroid carcinoma alter retinoic acid administration]. / Rediferenciación tumoral en carcinoma papilar de tiroides tras la administración de ácido retinoico.

Male patient, 73 year old, with papillary thyroid carcinoma treated by surgery, 131I and L-Tyroxine, with bone metastasis, detected by bone scintigraphy and CT scan, which negative radioiodine uptake. In order to induce tumoral redifferentiation, retinoic acid (70 mg/day) was administered for three months before 131I treatment. A radioiodine scan performed after treatment showed uptake in some of the bone metastasis. Nine months later, and due to disease progression, a second induction with retinoic acid was performed before 131I treatment. The radioiodine scan performed after treatment showed greater uptake and higher number of bone lesions than the previous scan.

Rediferenciación tumoral en carcinoma papilar de tiroides tras la administración de ácido retinoico / Tumor redifferentiation in papillary thyroid carcinoma after retinoic acid administration

Paciente varón de 73 años con carcinoma papilar de tiroides tratado con cirugía, 131I y L-Tiroxina, que presentó metástasis óseas, objetivadas por gammagrafía ósea y TAC, que no captaban 131I. Con el fin de inducir rediferenciación tumoral, se administró ácido retinoico (70 mg/día) durante tres meses previos a tratamiento con 131I. El rastreo postratamiento evidenció captación de 131I en algunas metástasis óseas. Por este motivo, y debido a progresión de la enfermedad, nueve meses más tarde se realizó una segunda inducción con ácido retinoico previa a tratamiento con 131I. En esta ocasión el rastreo postratamiento mostró captación de 131I de mayor grado de intensidad y en más lesiones óseas que las detectadas por el rastreo anterior (AU)

Male patient, 73 year old, with papillary thyroid carcinoma treated by surgery, 131I and L-Tyroxine, with bone metastasis, detected by bone scintigraphy and CT scan, which negative radioiodine uptake. In order to induce tumoral redifferentiation, retinoic acid (70 mg/day) was administered for three months after treatment showed uptake in some of the bone metastasis. Nine months later, and due to disease progression, a second induction with retinoic acid was performed before 131I treatment. The radioiodine scan performed after treatment showed greater uptake and higher number of bone lesions than the previous scan (AU)

[Role of direct radionuclide cystography and renal study by dimercaptosuccinic acid (DMSA) in the diagnosis and follow-up of vesicoureteral reflux]. / La cistografía isotópica directa y la gammagrafía renal con ácido dimercaptosuccínico (DMSA) en el diagnóstico y seguimiento del reflujo vesicoureteral.

AIM: To evaluate the role of isotopic studies in the diagnosis and follow-up of vesicoureteral reflux (VUR) and to present the results of our current protocol. MATERIAL AND METHODS: Forty three patients with VUR were retrospectively studied with a mean follow-up of 43 years (1-11 years). VUR was diagnosed by voiding cystourethrography and followed-up by direct radionuclide cystography. During the follow-up all patients were studied by means of renal DMSA scintigraphy (21 were also studied during the acute phase of febrile urinary tract infection). RESULTS: Eighty three renal units were examined. Voiding cystourethrography was positive for VUR in 49 renal units (59%; 8 grade I, 18 grade II, 15 grade III, and 8 grade IV). During the follow-up, direct radionuclide cystography showed decrease or disappearance of VUR in 29 renal units (35%; 4 grade I, 16 grade II, 7 grade III, and 2 grade IV). DMSA studies performed during the follow-up showed cortical lesions in 17 renal units (5 with VUR grade II, 7 with grade III, and 5 grade IV). Nine of 21 patients examined by DMSA during the acute phase of febrile urinary tract infection showed cortical damage (43%), and 6 of them (67%) progressed to cortical lesion in the follow-up DMSA. CONCLUSIONS: The present protocol allows for the correct diagnosis and control of VUR, the early detection of acute renal damage, and the control of its evolution.

La cistografía isotópica directa y la gammagrafía renal con ácido dimercaptosuccínico (DMSA) en el diagnóstico y seguimiento del reflujo vesicoureteral / Role of direct radionuclide cystography and renal study by dimercaptosuccinic acid (DMSA) in the diagnosis and follow-up of vesicoureteral reflux

Objetivo: Valorar la utilidad de la cistografía isotópica directa (CID) y de la gammagrafía renal con ácido dimercaptosuccínico (DMSA) en el diagnóstico y seguimiento del RVU, según los resultados obtenidos a partir del protocolo actual de nuestro centro. Material y Métodos: Se han estudiado retrospectivamente 43 pacientes diagnosticados de RVU con un período de seguimiento medio de 4 ñ 3 años (1-11 años). El diagnóstico de RVU se realizó mediante cistografía radiológica (CUMS) y el seguimiento mediante CUMS y/o CID. Durante el seguimiento se realizó gammagrafía renal con DMSA a todos los pacientes. Veintiún pacientes también fueron estudiados con DMSA durante la fase aguda de la infección urinaria febril. Resultados: Se exploraron 83 unidades renales. En el momento del diagnóstico la CUMS fue positiva para RVU en 49 unidades renales (59 per cent; 8 grado I, 18 grado II, 15 grado III y 8 grado IV). Durante el seguimiento por CID se observó disminución o desaparición del RVU en 29 unidades renales (35 per cent; 4 grado I, 16 grado II, 7 grado III y 2 grado IV). Durante el seguimiento el DMSA mostró lesiones corticales en 17 unidades renales (5 con RVU grado II, 7 grado III y 5 grado IV). Nueve de los 21 pacientes estudiados con DMSA durante la fase aguda de la infección urinaria febril presentaron afectación cortical (43 per cent), de los cuales 6 evolucionaron a lesión cortical en el DMSA de control (67 per cent). Conclusiones: El protocolo descrito permite diagnosticar y controlar el RVU, identificar precozmente la afectación renal y controlar su evolución (AU)

[Nephrourology and nuclear medicine today]. / Nefrourología y medicina nuclear en la actualidad.

OBJECTIVE: To review the radioisotope studies in Nephrourology that are frequently performed in the Nuclear Medicine Department, their clinical applications and diagnostic yield. METHODS/RESULTS: Radionuclide studies in Nephrourology allow evaluation of different aspects of renal function after intravenous injection of radioisotopes by blood volume/time (ml/min) measurements (glomerular filtration rate, effective renal plasma flow) or visualization in the form of images or graphic display (renal scintigraphy, sequential study, renography) that permit determination of the differential renal function. A sequential study, diuresis renography or angiotensin converting enzyme (ACE) inhibitor renography can be performed to evaluate the changes in renal function induced by the diuretics or ACE inhibitors. Radionuclide cystography permits detecting vesicoureteric reflux. These radioisotope studies are commonly utilized in detecting reflux nephropathy and renal scarring (renal scintigraphy and radionuclide cystography), obstructive nephropathy (diuresis renography), renovascular hypertension (ACE inhibitor renography) and in evaluating renal transplantation (sequential study, renography, diuresis renography and ACE inhibitor renography). CONCLUSION: Radionuclide studies have different applications in Nephrourology, some of which are considered to be diagnostic gold standards, such as renal scintigraphy with DMSA to detect cortical anomalies, ACE inhibitor renography to identify hypertensive patients that will not benefit from revascularization surgery and to determine the glomerular filtration rate. Other studies, such as diuretic renography, are not considered to be gold standards due to the lack of standardized protocols.

[Sympathetic reinnervation of the transplanted heart. Study using iodine-123 labeled meta-iodobenzylguanidine]. / Reinervación simpática del corazón trasplantado. Estudio realizado con metayodobenzilguanidina marcada con yodo-123.

INTRODUCTION AND OBJECTIVES: Metaiodobenzylguanidine (MIBG) is an analogue of norepinephrine and its cardiac uptake shows sympathetic innervation. During the heart transplantation the allograft becomes completely denervated. The present study was conducted to assess the evolution of sympathetic re-innervation after transplantation, and to related re-innervation with functional status. PATIENTS AND METHODS: We studied 31 patients from 6 months to 12 years after transplantation by 123I-MIBG studies to evaluate re-innervation and by rest/exercise radionuclide ventriculography to evaluate cardiac function. Myocardial MIBG uptake was quantified by calculating a heart-to-mediastinum ratio (HMR). An HMR > 1.8 was considered normal, moderate between 1.8 and 1.6, mild between 1.6 and 1.3, and absent < 1.3. RESULTS: HMR correlated with time after transplantation (r = 0.607; p < 0.001). HMR of patients studied after 2 years of transplantation was significantly higher (1.62 +/- 0.2 vs 1.34 +/- 0.2; p < 0.05). MIBG uptake was in the anterior region in 3 patients, in the antero-lateral region in 25, and in the antero-lateral and septal regions in 3. From a functional point of view, peak filling rate at exercise was higher in patients studied 2 years after the transplantation (2.7 +/- 0.8 edv/s vs 2.16 +/- 0.5 edv/s; p = 0.02). These patients also showed a higher increase of heart rate with exercise (p < 0.005 vs p < 0.01). CONCLUSIONS: Sympathetic re-innervation increase with time after heart transplantation, and is more frequently seen 2 years after transplantation. Sympathetic re-innervation first appears in the anterior or the antero-lateral regions. A complete re-innervation of the transplanted heart does not occur 12 years after transplantation.

[Evaluation of myocardial viability using perfusion cardiac SPECT. 201-thallium rest/redistribution, 201-thallium rest/reinjection and technetium 99m tetrofosmin rest/postnitrates]. / Valoración de la viabilidad miocárdica mediante SPET cardíaco de perfusión. Talio-201 reposo/redistribución, talio-201 reposo/reinyección y tecnecio-99m tetrofosmina reposo/posnitratos.

INTRODUCTION AND OBJECTIVES: It has been demonstrated that nitrate administration enhances the detection of myocardial viability in thallium-201 and technetium-99m sestamibi myocardial perfusion studies. The aim of this study was to assess the influence of nitrate administration on technetium-99m tetrofosmin myocardial uptake in patients with coronary artery disease and left ventricular dysfunction. PATIENTS AND METHODS: Twenty eight patients with coronary artery disease, previous myocardial infarction and left ventricular ejection fraction < 40% underwent, within 48 hours, rest/postnitroglycerin (0.4 mg sublingually) technetium-99m tetrofosmin single photon emission tomography (SPET), comparing these results with that of thallium-201 rest/redistribution SPET in 13 patients (first group) and with that of thallium-201 rest/reinjection SPET in the other 15 patients (second group). Tomograms based on the 3 spatial planes were divided into 15 segments and regional tracer uptake was quantitatively analysed. Viability was defined as presence of tracer uptake > or = 50% of peak activity. RESULTS: The percentage of peak activity at rest or after nitrate administration of technetium-99m tetrofosmin correlated, with that of thallium-201, at rest and after redistribution or reinjection (r = 0.8; p < 0.001). On resting technetium-99m tetrofosmin studies 167 of the 420 segments that were analysed had < 50% of peak activity. 14.5% of these segments showed reversibility after nitrate administration, with an increase in 99mTc-tetrofosmin uptake from 45 +/- 5% to 55 +/- 4% of peak activity (p = 0.001), in the first group, and from 40 +/- 9% to 57 +/- 9% of peak activity (p = 0.003), in the second group. Overall agreement between rest/postnitroglycerin technetium-99m tetrofosmin SPET studies and rest/redistribution or rest/reinjection thallium-201 SPET studies, regarding the presence of myocardial viability, was 87% and 90%, respectively. All except one reversible segments on tetrofosmin studies after nitrates had viability criteria on thallium studies. CONCLUSIONS: Nitrate administration at rest enhances the detection of myocardial viability using technetium-99m tetrofosmin SPET, correlating with viability criteria observed on thallium studies. It represents a simple and useful technique in the assessment of myocardial viability.

[Functional dyspepsia, gastric emptying of solids, and Helicobacter pylori infection]. / Dispepsia funcional, vaciado gástrico de sólidos e infección por Helicobacter pylori.

UNLABELLED: The origin of functional dyspepsia (FD) is unknown, however, abnormal gastric emptying and infection by H. pylori have been suggested as possible causes. OBJECTIVE: The aim of this study was to test the hypothesis that infection by H. pylori could be related to alterations in gastric emptying of solids and play a role in the pathophysiology of dyspepsia. METHODS: Studies were performed on 12 controls: 6 males, 6 females, age 40 +/- 13, and on 45 FD patients: 15 males and 30 females, age 43.5 +/- 12. Clinical criteria for FD diagnosis were post-prandial epigastric pain, nausea, vomiting or epigastric bloating, with normal blood test, upper endoscopy and abdominal ultrasound. Diagnosis of H. pylori infection was either by growth positive on culture of antral biopsy or by all of the following: on Gram stain, urease test positive and visualization of microorganisms in the antral biopsy. Gastric emptying of solids was studied with a radio-nuclide technique. Patients were prospectively classified in 4 groups according to the main symptom: reflux-like, ulcer-like, dysmotility, and non-specific. RESULTS: H. pylori infection was observed in 21/32 (66%) FD patients. No significant differences in the gastric emptying of solids between the control group and patients with FD (tl/2 80 +/- 17 minutes vs 75 +/- 16 min). The presence of H. pylori infection did not influence gastric emptying rates (78 +/- 16 minutes in infected patients vs 73 +/- 15 min in non infected patients). Gastric emptying times were similar among the four subgroups of FD patients. CONCLUSIONS: No significant differences in gastric emptying of solids were found in H. pylori infected persons as compared with the controls. These findings suggest that H. pylori infection and/or changes in gastric emptying of solids do not play a role in the pathophysiology of FD.

Patterns of evolution of myocyte damage after human heart transplantation detected by indium-111 monoclonal antimyosin.

The indium-111 labeled Fab fragment of antimyosin monoclonal antibody was used to study cardiac rejection and the time course of myocyte damage after transplantation. Fifty-three studies were performed in 21 patients, 17 men and 4 women, aged 19 to 54 years (mean 37 +/- 8), from 7 to 40 months after transplantation. Repeat studies were available in 8, and 10 were studied after the first year of transplantation. A heart-to-lung ratio was used for quantitation of uptake (normal 1.46 +/- 0.04). Differences between absent (1.69 +/- 0.29) and moderate (1.90 +/- 0.36) rejection were significant (p less than 0.03). Antimyosin ratio at 1 to 3 months (1.89 +/- 0.35) differed from that at greater than 12 months (1.65 +/- 0.2) (p less than 0.01). Repeat studies revealed a decrease in antimyosin ratio in 5 patients with uneventful clinical course; 2 had persistent activity after transplantation and suffered heart failure from rejection. After 1 year of transplantation uptake was within normal limits in 7 of 10 patients, and high uptake was associated with vascular rejection in 1. Because they can define evolving patterns of myocardial lesion activity, antimyosin studies could be useful both in patient management and in concentrating resources for those patients who most require them. The heart-to-lung ratio is suggested to monitor sequentially the degree of myocyte damage after transplantation.