68Ga-DOTATATE PET/CT, 99mTc-HYNIC-octreotide SPECT/CT, and whole-body MR imaging in detection of neuroendocrine tumors: a prospective trial.

UNLABELLED: There are different metabolic imaging methods, various tracers, and emerging anatomic modalities to stage neuroendocrine tumor (NET). We aimed to compare NET lesion detectability among (99m)Tc-hydrazinonicotinamide (HYNIC)-octreotide (somatostatin receptor scintigraphy [SSRS]) SPECT/CT, (68)Ga-DOTATATE PET/CT, and whole-body diffusion-weighted MR imaging (WB DWI). METHODS: Nineteen consecutive patients (34-77 y old; mean, 54.3 ± 10.4 y old; 10 men and 9 women) underwent SSRS SPECT/CT, (68)Ga-DOTATATE PET/CT, and WB DWI. Images were acquired with a maximum interval of 3 mo between them and were analyzed with masking by separate teams. Planar whole-body imaging and SPECT/CT were performed from thorax to pelvis using a double-head 16-slice SPECT/CT scanner 4 h after injection of 111-185 MBq of (99m)Tc-HYNIC-octreotide. (68)Ga-DOTATATE PET/CT was performed from head to feet using a 16-slice PET/CT scanner 45 min after injection of 185 MBq of tracer. WB DWI was performed in the coronal plane using a 1.5-T scanner and a body coil. The standard method of reference for evaluation of image performance was undertaken: consensus among investigators at the end of the study, clinical and imaging follow-up, and biopsy of suggestive lesions. RESULTS: McNemar testing was applied to evaluate the detectability of lesions using (68)Ga-DOTATATE PET/CT in comparison to SSRS SPECT/CT and WB DWI: a significant difference in detectability was noted for pancreas (P = 0.0455 and P = 0.0455, respectively), gastrointestinal tract (P = 0.0455 and P = 0.0455), and bones (P = 0.0082 and P = 0.0082). Two unknown primary lesions were identified solely by (68)Ga-DOTATATE PET/CT. (68)Ga-DOTATATE PET/CT, SSRS SPECT/CT, and WB DWI demonstrated, respectively, sensitivities of 0.96, 0.60, and 0.72; specificities of 0.97, 0.99, and 1.00; positive predictive values of 0.94, 0.96, and 1.00; negative predictive values of 0.98, 0.83, and 0.88; and accuracies of 0.97, 0.86, and 0.91. CONCLUSION: (68)Ga PET/CT seems to be more sensitive for detection of well-differentiated NET lesions, especially for bone and unknown primary lesions. NET can be staged with (68)Ga-DOTATATE PET/CT. WB DWI is an efficient new method with high accuracy and without ionizing radiation exposure. SSRS SPECT/CT should be used only when (68)Ga-DOTATATE PET/CT and WB DWI are not available.

Cintilografia de perfusão miocárdica na detecção da isquemia silenciosa em pacientes diabéticos assintomáticos / Myocardial perfusion scintigraphy in the detection of silent ischemia in asymptomatic diabetic patients

OBJECTIVE: This study was aimed to evaluate myocardial perfusion in asymptomatic patients with type 1 (DM1) and type 2 diabetes mellitus (DM2) without previous diagnoses of coronary artery disease (CAD) or cerebral infarction. MATERIALS AND METHODS: Fifty-nine consecutive asymptomatic patients (16 DM1, 43 DM2) underwent myocardial perfusion scintigraphy with 99mTc-sestamibi (MPS). They were evaluated for body mass index, metabolic control of DM, type of therapy, systemic arterial hypertension, dyslipidemia, nephropathy, retinopathy, peripheral neuropathy, smoking, and familial history of CAD. RESULTS: MPS was abnormal in 15 patients (25.4%): 12 (20.3%) with perfusion abnormalities, and 3 with isolated left ventricular dysfunction. The strongest predictors for abnormal myocardial perfusion were: age 60 years and above (p = 0.017; odds ratio [OR] = 6.0), peripheral neuropathy (p = 0.028; OR = 6.1), nephropathy (p = 0.031; OR = 5.6), and stress ECG positive for ischemia (p = 0.049; OR = 4.08). CONCLUSION: Silent myocardial ischemia occurs in more than one in five asymptomatic diabetic patients. The strongest predictors of ischemia in this study were: patient age, peripheral neuropathy, nephropathy, retinopathy and a stress ECG positive for ischemia.

OBJETIVO: Este estudo teve por finalidade avaliar a perfusão miocárdica de pacientes com diabetes mellitus tipo 1 (DM1) e tipo 2 (DM2) assintomáticos, sem diagnóstico prévio de doença arterial coronariana (DAC) ou acidente vascular cerebral. MATERIAIS E MÉTODOS: Cinquenta e nove pacientes consecutivos (16 DM1, 43 DM2) foram submetidos a cintilografia de perfusão miocárdica com sestamibi-99mTc (CPM). Foram avaliados quanto ao índice de massa corpórea, controle metabólico do diabetes, dislipidemia, terapia para o diabetes, hipertensão arterial sistêmica, nefropatia, retinopatia, neuropatia periférica, tabagismo e história familiar de DAC. RESULTADOS: CPM foi anormal em 25,4%: 12 (20,3%) com alterações de perfusão e 3 com disfunção ventricular esquerda isolada. Os mais fortes preditores de perfusão miocárdica anormal foram: idade igual ou maior a 60 anos (p = 0,017, odds ratio [OR] = 6,0), neuropatia periférica (p = 0,028, OR = 6,1), nefropatia (p = 0,031, OR = 5,6) e ECG de esforço positivo para isquemia (p = 0,049, OR = 4,08). CONCLUSÃO: A isquemia miocárdica silenciosa ocorre em mais de um em cada cinco diabéticos assintomáticos. Os mais fortes preditores de isquemia foram: idade avançada, neuropatia periférica, nefropatia, retinopatia e ECG de esforço positivo para isquemia.

Brain Perfusion Impairment in Neurologically Asymptomatic Adult Patients with Sickle-Cell Disease Shown by Voxel-Based Analysis of SPECT Images.

Cerebrovascular lesions are frequently observed in patients with sickle-cell disease (SCD) and these structural lesions are preceded by insidious perfusion deficits. Our aim was to investigate the presence of brain perfusion deficits in neurologically asymptomatic SCD patients, especially affecting microvessels. For this study, 42 SCD patients [33 sickle-cell anemia (HbSS), 6 sickle hemoglobin C disease (HbSC), and 3 sickle ß-thalassemia disease (HbSß)] with mean hematocrit of 25.1 (±4.85; 15.6-38.5) underwent brain perfusion single photon emission computerized tomography (SPECT) using the tracer (99m)Tc-ECD. Images from SCD patients were compared to images of a healthy control group (29 females and 20 males, mean age 31 ± 8; range 25-49 years). Images underwent voxel-wise comparison of regional tracer uptake using paired t-test to estimate the probability of each voxel to have an increased or decreased tracer uptake. When compared to controls, SCD patients exhibited significantly reduced tracer uptake in basal ganglia and thalami, the anterior frontal region and the watershed region of the temporo-parietal-occipital transition (p < 0.05). Our study showed that neurologically asymptomatic adult SCD patients exhibit a pattern of reduced (99m)Tc-ECD tracer uptake demonstrated by SPECT. Early diagnosis of this cerebral vasculopathy has prognostic implications and can be determinant in considering therapeutic alternatives to avoid increasing brain lesion load and progressive disability.

Estudo do esvaziamento gástrico por cintilografia em pacientes com insuficiência renal crônica / Gastric emptying study by scintigraphy in patients with chronic renal failure

JUSTIFICATIVA E OBJETIVOS: O presente estudo teve como objetivo o esvaziamento gástrico (EG) nos pacientes com insuficiência renal crônica (IRC). MATERIAL E MÉTODO: Foram estudados 30 pacientes com IRC, 16 em tratamento clínico conservador (TCC) e 14 em hemodiálise (THD) há mais de seis meses. O grupo-controle (CTL) foi constituído por 18 voluntários assintomáticos. O método de estudo do esvaziamento gástrico (EG) foi a cintilografia. A refeição-teste padronizada foi uma omelete de três ovos de galinha preparada com enxofre coloidal marcado com 185 MBq de tecnécio-99 m. Foram estudados as curvas de retenção gástrica e, a partir delas, obtido o T½ do EG. Considerou-se normal o valor de T½ correspondente à média dos valores de T½ do grupo-controle mais duas vezes o desvio-padrão. Os testes estatísticos utilizados foram o de χ² e o de Kruskal Wallis. RESULTADOS: Não houve diferença estatisticamente significativa em relação às curvas de retenção gástrica total e ao T½ de EG, que foi semelhante nos três grupos estudados. Nove pacientes apresentaram T½ de EG elevado, acima de 125 minutos. Estes pacientes estavam igualmente distribuídos entre ambos os sexos e entre os grupos TCC e THD. CONCLUSÕES: Concluiu-se que a taxa de retenção gástrica e o T½ de EG em pacientes com IRC em TCC e THD não difere do grupo de pacientes sadios. A hemodiálise não parece diminuir o risco de retenção gástrica em pacientes com IRC.

BACKGROUND AND OBJECTIVES: This study had the purpose of studying gastric emptying in patients with chronic renal failure. MATERIAL AND METHOD: Thirty patients with chronic renal failure were studied, 16 in conservative clinical treatment and 14 in hemodialysis for over six months. The control group (CTL) was composed of 18 asymptomatic volunteers. The method of gastric emptying study was scintigraphy. The standardized test meal was an omelet of three chicken eggs prepared with colloidal sulfur marked with 185 MBq of 99 m technetium. Gastric retention curves were studied and T½ of gastric emptying was obtained from them. A T½ value corresponding to the average of T½ values of control group plus twice standard deviation was considered nornmal. Statistical tests used were χ2 and Kruskal-Wallis. RESULTS: There was no statistically significant difference with regard to total gastric retention curves and T½ of gastric emptying, which was similar in three studied groups. Nine patients had high T½ of gastric emptying, above 125 minutes. These patients were equally distributed among both genders and conservative clinical treatment and hemodialysis groups. CONCLUSIONS: We concluded that gastric retention rate and T½ of gastric emptying in patients with chronic renal failure in conservative clinical treatment and hemodialysis does not differ from the healthy patients group. Hemodialysis does not seem to reduce the risk of gastric retention in patients with chronic renal failure.

JUSTIFICATIVA Y OBJETIVOS: La literatura indica factores de rutina con un impacto negativo sobre la calidad de vida de los anestesiólogos. Este trabajo pretende comparar la percepción de la calidad de vida de anestesiólogos y médicos no anestesiólogos. MÉTODO: Estudio transversal procedente de tres cuestionarios específicos (epidemiológico, WHOQOL-BREF y SF-12®) aplicados en anestesiólogos (Grupo A) y no anestesiólogos (Grupo NA), de un hospital general universitario y de un tercer grupo de anestesiólogos del interior del Estado (Grupo I). Los análisis de las variables epidemiológicas (programa SPSS) y los relacionadas con los dominios de calidad de vida del WHOQOL, fueron interpretados por medio del análisis multivariado. RESULTADOS: El número de respondedores del WHOQOL-BREF en el Grupo A = 67; Grupo NA = 69; Grupo I = 53. El grupo de anestesiólogos del interior (Grupo I) fue excluido del estudio por falta de un Nº adecuado para los análisis estadísticos. El total de respondedores para comprobar la puntuación SF-12® fue de 61 en el Grupo A y 68 en el NA. Para la herramienta WHOQOL-BREF, las puntuaciones del dominio físico fueron 72,97 ± 11,78 para A y 77,17 ± 10,85 para NA (p < 0,05), en el psicológico 66,44 ± 13,66 para A y 71,79 ± 11,48 para NA (p < 0,05), en el dominio de relacionamiento social 64,67 ± 19,08 para A y 73,36 ± 15,37 para NA (p < 0,01), y en el dominio medio ambiente 68,14 ± 11,56 para A y 72,37 ± 10,07 para NA (p < 0,05). En el SF-12® los componentes físico y mental no mostraron diferencias estadísticas. CONCLUSIONES: La percepción de la calidad de vida de los anestesiólogos fue consistentemente inferior a la de los médicos en general para la muestra estudiada.

Gastric emptying study by scintigraphy in patients with chronic renal failure.

BACKGROUND AND OBJECTIVES: This study had the purpose of studying gastric emptying in patients with chronic renal failure. MATERIAL AND METHOD: Thirty patients with chronic renal failure were studied, 16 in conservative clinical treatment and 14 in hemodialysis for over six months. The control group (CTL) was composed of 18 asymptomatic volunteers. The method of gastric emptying study was scintigraphy. The standardized test meal was an omelet of three chicken eggs prepared with colloidal sulfur marked with 185 MBq of 99m technetium. Gastric retention curves were studied and T½ of gastric emptying was obtained from them. A T½ value corresponding to the average of T½ values of control group plus twice standard deviation was considered nornmal. Statistical tests used were χ(2) and Kruskal-Wallis. RESULTS: There was no statistically significant difference with regard to total gastric retention curves and T½ of gastric emptying, which was similar in three studied groups. Nine patients had high T½ of gastric emptying, above 125 minutes. These patients were equally distributed among both genders and conservative clinical treatment and hemodialysis groups. CONCLUSIONS: We concluded that gastric retention rate and T½ of gastric emptying in patients with chronic renal failure in conservative clinical treatment and hemodialysis does not differ from the healthy patients group. Hemodialysis does not seem to reduce the risk of gastric retention in patients with chronic renal failure.

The value of positron-emission tomography/computed tomography for radiotherapy treatment planning: a single institutional series.

BACKGROUND: This study aimed to compare the clinical target volumes (CTV) delineated by computed tomography (CT) and positron emission tomography (PET)/CT using fluoro-deoxy-glucose to assess the impact of using PET information for radiotherapy (RT) planning. METHODS: We retrospectively reviewed data on patients with tumors from different sites who had indications for RT and had undergone RT treatment planning with PET/CT at our institution between July 2003 and July 2009. Statistical analysis included the comparison of CTV planned for treatment only by CT (CTV(CT)) with that by PET/CT (CTV(PET)) using the Wilcoxon test for paired samples. RESULTS: Of 105 patients eligible for analysis, 56.2% were men. The most common diagnoses were head and neck cancer (28.6%), lung cancer (21.9%), lymphoma (11.4%), upper gastrointestinal (10.5%), and others (14.3%). Comparison of CTV(CT) and CTV(PET) revealed that RT planning has changed in 77% of cases because of PET/CT additional information, with impact on treatment volume varying according to diagnosis. Despite the absolute difference observed between median CTVs, there was no significant difference between CTV(CT) and CTV(PET) (114 vs. 90.4 ml, respectively; P=0.1266), considering all patients. Nonetheless, a significant difference between CTVs delineated by CT and PET/CT was found when only head and neck, lung and lymphoma cases--representing more than 60% of the sample--were examined (112.5 and 80.7 ml, respectively; P=0.0053). CONCLUSION: We have shown that PET/CT use promotes significant changes in the CTV delineated for treatment of different tumors, modifying RT planning. Our data suggest that PET/CT has a good potential for optimizing RT treatment planning, especially in head and neck, lung, and lymphoma tumors.

Functional electrical stimulation improves brain perfusion in cranial trauma patients.

OBJECTIVE: Demonstrate brain perfusion changes due to neuronal activation after functional electrical stimulation (FES). METHOD: It was studied 14 patients with hemiplegia who were submitted to a program with FES during fourteen weeks. Brain perfusion SPECT was performed before and after FES therapy. These patients were further separated into 2 groups according to the hemiplegia cause: cranial trauma and major vascular insults. All SPECT images were analyzed using SPM. RESULTS: There was a significant statistical difference between the two groups related to patient's ages and extent of hypoperfusion in the SPECT. Patients with cranial trauma had a reduction in the hypoperfused area and patients with major vascular insult had an increase in the hypoperfused area after FES therapy. CONCLUSION: FES therapy can result in brain perfusion improvement in patients with brain lesions due to cranial trauma but probably not in patients with major vascular insults with large infarct area.

Functional electrical stimulation improves brain perfusion in cranial trauma patients / A terapia com estímulo elétrico funcional pode melhorar a perfusão cerebral no SPECT em pacientes com trauma craniano

OBJECTIVE: Demonstrate brain perfusion changes due to neuronal activation after functional electrical stimulation (FES). METHOD: It was studied 14 patients with hemiplegia who were submitted to a program with FES during fourteen weeks. Brain perfusion SPECT was performed before and after FES therapy. These patients were further separated into 2 groups according to the hemiplegia cause: cranial trauma and major vascular insults. All SPECT images were analyzed using SPM. RESULTS: There was a significant statistical difference between the two groups related to patient's ages and extent of hypoperfusion in the SPECT. Patients with cranial trauma had a reduction in the hypoperfused area and patients with major vascular insult had an increase in the hypoperfused area after FES therapy. CONCLUSION: FES therapy can result in brain perfusion improvement in patients with brain lesions due to cranial trauma but probably not in patients with major vascular insults with large infarct area.

OBJETIVO: Demonstrar mudanças na perfusão cerebral devido à ativação neuronal depois de estimulação elétrica funcional (EEF). MÉTODO: Foram estudados 14 pacientes com hemiplegia submetidos a quatorze semanas de um programa com EEF. O SPECT de perfusão cerebral foi realizado antes e depois da terapia com EEF. Estes pacientes foram separados em 2 grupos com relação à causa da hemiplegia: trauma craniano e acidente vascular cerebral (AVC). As imagens de SPECT foram analisadas usando SPM. RESULTADOS: Houve diferença estatisticamente significativa entre os dois grupos relacionada a idade dos pacientes e extensão da hipoperfusão. Os pacientes com trauma craniano tiveram redução na área de hipoperfusão e pacientes com AVC tiveram aumento na área de hipoperfusão após terapia com EEF. CONCLUSÃO: A terapia com EEF pode levar a melhora na perfusão cerebral em pacientes com lesões cerebrais secundárias a trauma craniano; entretanto, provavelmente não em pacientes com extensas áreas de infarto secundárias a AVC.

Cumulative doses of radioiodine in the treatment of differentiated thyroid carcinoma: knowing when to stop / Doses cumulativas de iodo radioativo no tratamento do carcinoma diferenciado de tireoide: sabendo a hora de parar

OBJECTIVE: Evaluate the efficacy of cumulative doses (CDs) of 131I-iodide therapy (RIT) in differentiated thyroid cancer (DTC). SUBJECTS AND METHODS: The probability of progressive disease according to CDs was evaluated in patients < 45 years old and > 45 years old and correlated to tumor-node-metastasis (TNM), thyroglobulin values, histological types and variants, age, and zduration of the disease. RESULTS: At the end of a follow-up period of 69 ± 56 months, 85 out of 150 DTC patients submitted to fixed doses RIT had no evidence of disease, 47 had stable disease and 18 had progressive disease. Higher CDs were used in the more aggressive variants (p < 0.0001), higher TNM stages (p < 0.0001), and follicular carcinomas (p = 0.0034). Probability of disease progression was higher with CDs > 600 mCi in patients > 45 years old and with CDs > 800 mCi in patients < 45 years. CONCLUSION: Although some patients may still respond to high CDs, the impact of further RIT should be carefully evaluated and other treatment strategies may be warranted.

OBJETIVO: Avaliar a eficácia de doses cumulativas (DCs) da terapia com iodeto-131I (RIT) no câncer diferenciado de tiroide (CDT). SUJEITOS E MÉTODOS: A probabilidade de doença em progressão conforme a DC foi calculada em pacientes com idade < 45 e > 45 anos e correlacionada com o TNM, valores de tiroglobulina sérica, tipos histológicos e variantes, idade e tempo de doença. RESULTADOS: Ao final de um seguimento de 69 ± 56 meses, 85 dos 150 pacientes CDT submetidos a doses fixas de RIT não tinham evidência de doença, 47 tinham doença estável e 18, doença progressiva. DCs mais elevadas foram usadas nas variantes agressivas (p < 0,0001), maior estágio TNM (p < 0,0001) e nos carcinomas foliculares (p = 0,0034). A probabilidade de doença em progressão foi maior com DCs > 600 mCi em pacientes > 45 anos e com DCs > 800 mCi em pacientes < 45 anos. CONCLUSÃO: Apesar de alguns pacientes ainda responderem a altas DCs, o impacto de RITs deve ser cuidadosamente avaliado e outras estratégias terapêuticas devem ser consideradas.

Impact of [F-18] FDG-PET/CT in the restaging and management of patients with malignant melanoma.

PURPOSE: To assess the impact of [F-18] FDG-PET/CT on the restaging and changing management of patients with malignant melanoma. METHODS: Seventy-eight patients (32 female, 27-83 years) were reviewed. Treatment planning before and after [F-18] FDG-PET/CT scan was evaluated for changes in the management of the disease. Restaging was classified according to the disease extent as follows: local recurrence, locoregional recurrence or distant recurrence. Initial restaging of patients was as follows: local recurrence in 11 patients, locoregional recurrence in 23 patients and distant recurrence in 44 of 78 patients. All the patients were injected with 370 MBq of [F-18] FDG and imaged from the head to feet after 60 min. All the patients fasted for 4-6 h before imaging and blood glucose levels were below 140 mg/dl. Images were taken using a PET/CT scanner (Siemens Biograph). Two nuclear medicine physicians and a radiologist (all experienced in oncology) interpreted the images. RESULTS: In 27% of the patients the management was changed after the [F-18] FDG-PET/CT studies. Upstaging from locoregional recurrence to distant recurrence occurred in a striking 5 of 23 (22%) patients. The sensitivity, specificity and positive and negative predictive values for lesion detection were 95%, and accuracy was 94.9%. There were two false-positive and two false-negative studies. CONCLUSION: [F-18] FDG-PET/CT seems to be a valuable diagnostic tool in restaging and management of patients with malignant melanoma suspected of recurrence especially in patients with locoregional recurrence and distant recurrence.

Brain SPECT in mesial temporal lobe epilepsy: comparison between visual analysis and SPM.

OBJECTIVE: To compare the accuracy of SPM and visual analysis of brain SPECT in patients with mesial temporal lobe epilepsy (MTLE). METHOD: Interictal and ictal SPECTs of 22 patients with MTLE were performed. Visual analysis were performed in interictal (VISUAL(inter)) and ictal (VISUAL(ictal/inter)) studies. SPM analysis consisted of comparing interictal (SPM(inter)) and ictal SPECTs (SPM(ictal)) of each patient to control group and by comparing perfusion of temporal lobes in ictal and interictal studies among themselves (SPM(ictal/inter)). RESULTS: For detection of the epileptogenic focus, the sensitivities were as follows: VISUAL(inter)=68%; VISUAL(ictal/inter)=100%; SPM(inter)=45%; SPM(ictal)=64% and SPM(ictal/inter)=77%. SPM was able to detect more areas of hyperperfusion and hypoperfusion. CONCLUSION: SPM did not improve the sensitivity to detect epileptogenic focus. However, SPM detected different regions of hypoperfusion and hyperperfusion and is therefore a helpful tool for better understand pathophysiology of seizures in MTLE.

Brain hypoperfusion in adolescents dependent of multiple drugs.

UNLABELLED: Brain SPECT imaging (BSI) with statistical parametric mapping (SPM) offers a clear and accurate vision of perfusion changes. OBJECTIVE: To study brain perfusion abnormalities in adolescents' dependent of multiple drugs. METHOD: Sixteen male patients (15.1 + or - 2.1 years) were submitted to (99m)Tc-HMPAO BSI with SPM. RESULTS: Cortical hypoperfusion occurred in 7/16 patients (44%). There was a significant inverse correlation between the number of hypoperfused regions and the patient's age (p= -0.6737; p=0.004) and with the age when the drug dependence began (p= -0.5616; p=0.023). There was also a tendency towards an inverse correlation between regions of hypoperfusion and the duration of the drug dependence. CONCLUSION: BSI with SPM can help detect hypoperfusion in adolescents dependent on multiple drugs. The younger the patients, the more regions of hypoperfusion are noted. Probably, the neuronal plasticity has an important role in this phenomenon because the highest neural activity occurs in childhood.

Brain hypoperfusion in adolescents dependent of multiple drugs / Hipoperfusão cerebral em adolescentes dependentes de múltiplas drogas

Brain SPECT imaging (BSI) with statistical parametric mapping (SPM) offers a clear and accurate vision of perfusion changes. OBJECTIVE: To study brain perfusion abnormalities in adolescents' dependent of multiple drugs. METHOD: Sixteen male patients (15.1±2.1 years) were submitted to 99mTc-HMPAO BSI with SPM. RESULTS: Cortical hypoperfusion occurred in 7/16 patients (44 percent). There was a significant inverse correlation between the number of hypoperfused regions and the patient's age (p= -0.6737; p=0.004) and with the age when the drug dependence began (p= -0.5616; p=0.023). There was also a tendency towards an inverse correlation between regions of hypoperfusion and the duration of the drug dependence. CONCLUSION: BSI with SPM can help detect hypoperfusion in adolescents dependent on multiple drugs. The younger the patients, the more regions of hypoperfusion are noted. Probably, the neuronal plasticity has an important role in this phenomenon because the highest neural activity occurs in childhood.

SPECT cerebral (SC) com statistical parametric mapping (SPM) oferece uma visão clara e acurada de alterações perfusionais. OBJETIVO: Avaliar anormalidades perfusionais cerebrais em adolescentes usuários de múltiplas drogas. MÉTODO: Dezesseis pacientes masculinos (15,1±2,1 anos) foram submetidos a SC com SPM utilizando-se HMPAO-99mTc. RESULTADOS: Hipoperfusão cortical ocorreu em 7/16 pacientes (44 por cento). Houve uma significativa correlação inversa entre o número de áreas hipoperfundidas e a idade dos pacientes (p= -0,6737; p=0,004) e com a idade quando iniciaram o abuso das drogas (p= -0,5616; p=0,023). Também houve uma tendência para uma correlação inversa entre as áreas de hipoperfusão e a duração do abuso de drogas. CONCLUSÃO: SC com SPM pode auxiliar na detecção de hipoperfusão cortical em adolescentes dependentes de múltiplas drogas. Quanto menor a idade, mais áreas de hipoperfusão são identificadas. Provavelmente a plasticidade neuronal tem importante papel neste fenômeno, pois a maior atividade neuronal ocorre na infância.

Brain SPECT in mesial temporal lobe epilepsy: comparison between visual analysis and SPM / SPECT cerebral na epilepsia de lobo temporal mesial: comparação entre análise visual e SPM

OBJECTIVE: To compare the accuracy of SPM and visual analysis of brain SPECT in patients with mesial temporal lobe epilepsy (MTLE). METHOD: Interictal and ictal SPECTs of 22 patients with MTLE were performed. Visual analysis were performed in interictal (VISUAL(inter)) and ictal (VISUAL(ictal/inter)) studies. SPM analysis consisted of comparing interictal (SPM(inter)) and ictal SPECTs (SPM(ictal)) of each patient to control group and by comparing perfusion of temporal lobes in ictal and interictal studies among themselves (SPM(ictal/inter)). RESULTS: For detection of the epileptogenic focus, the sensitivities were as follows: VISUAL(inter)=68 percent; VISUAL(ictal/inter)=100 percent; SPM(inter)=45 percent; SPM(ictal)=64 percent and SPM(ictal/inter)=77 percent. SPM was able to detect more areas of hyperperfusion and hypoperfusion. CONCLUSION: SPM did not improve the sensitivity to detect epileptogenic focus. However, SPM detected different regions of hypoperfusion and hyperperfusion and is therefore a helpful tool for better understand pathophysiology of seizures in MTLE.

OBJETIVO: Comparar a acurácia do SPM com a análise visual na detecção do foco epileptogênico e alterações perfusionais à distância no SPECT cerebral. MÉTODO: Foram realizados os SPECTs ictal e interictal de 22 pacientes com epilepsia de lobo temporal mesial (ELTM). A análise visual foi realizada nos estudos interictal (VISUAL(inter)) e ictal (VISUAL(ictal/inter)). Na análise com SPM foi comparado o estudo interictal (SPM(inter)) e ictal (SPM(ictal)) de cada paciente com o grupo controle e comparou-se a perfusão dos lobos temporais entre os estudos ictal e interictal (SPM(ictal/inter)). RESULTADOS: Para a detecção do foco epileptogênico, as sensibilidades foram as seguintes: VISUAL(inter)=68 por cento; VISUAL(ictal/inter)=100 por cento; SPM(inter)=45 por cento; SPM(ictal)=64 por cento and SPM(ictal/inter)=77 por cento. O SPM foi capaz de detectar mais áreas de hiperperfusão e hipoperfusão. CONCLUSÃO: O SPM não aumentou a sensibilidade na detecção do foco epileptogênico. Entretanto, o SPM detectou diferentes regiões de hipoperfusão e hiperperfusão e portanto, ele pode ser uma ferramenta de ajuda para se melhor entender a patofisiologia das crises na ELTM.

Tc-99m sestamibi thyroid imaging in patients on chronic amiodarone treatment: a comparison with Tc-99m pertechnetate imaging.

PURPOSE OF THE REPORT: To compare thyroid imaging using Tc-99m sestamibi with the standard Tc-99m pertechnetate scintigraphy in patients on chronic use of amiodarone. MATERIALS AND METHODS: A total of 23 patients on oral amiodarone for at least 4 months had thyroid scintigraphy and uptake measurement using Tc-99m pertechnetate and Tc-99m sestamibi. Thyroid function was evaluated by measuring serum concentrations of thyrotropin, free thyroxine, and free triiodothyronine, and antithyroglobulin and antithyroperoxidase antibodies. RESULTS: Ten of the 23 patients were euthyroid, 9 hypothyroid, and 4 hyperthyroid, with normal, increased, and decreased serum thyrotropin, respectively. All euthyroid patients had markedly decreased thyroid Tc-99m pertechnetate uptake and normal or slightly increased Tc-99m sestamibi uptake, except for one patient who had increased uptake of both radiotracers. One of the 4 hyperthyroid patients had Graves' disease and markedly increased thyroid uptake of both tracers. The other 3 hyperthyroid patients had normal or decreased Tc-99m pertechnetate uptake and increased Tc-99m sestamibi uptake. Differently than expected, all 9 hypothyroid patients had normal or increased uptake of both radiopharmaceuticals. CONCLUSIONS: This study suggests that Tc-99m sestamibi may be an alternative tracer for thyroid scintigraphy and uptake measurement of patients on chronic use of amiodarone. Tc-99m sestamibi seems to be better than Tc-99m pertechnetate for the scintigraphic evaluation of the thyroid of euthyroid and hyperthyroid patients.

Technetium-99m-L,L-ethylenedicysteine is more effective than technetium-99m diethylenetriamine penta-acetic acid for excluding obstruction in patients with pyelocalicinal dilation.

OBJECTIVE: To evaluate the utility of diuretic dynamic renal scintigraphy (DDRS) with technetium-99m-L,L-ethylenedicysteine ((99m)Tc-EC) in patients with indeterminate or possible false-positive results for urinary obstruction by technetium-99m diethylenetriamine penta-acetic acid ((99m)Tc-DTPA) DDRS. METHODS: A total of 92 patients (63 male; mean age, 16.6 +/- 21.25 years) were studied, with a total of 103 kidneys presenting indeterminate (20/103) or possible false-positive results for obstruction attributable to reduced renal function or severe kidney dilation (83/103) by (99m)Tc-DTPA DDRS (<60% of radiopharmaceutical excreted in 20 minutes-half-time clearance [T(1/2)] >15 minutes). Patients were reimaged after intravenous injection of (99m)Tc-EC, with dynamic images before and after furosemide administration using the same acquisition parameters applied in the previous (99m)Tc-DTPA study. Time interval between (99m)Tc-DTPA and (99m)Tc-EC renograms was 2-64 days. The percentage of excreted material 20 minutes after furosemide was calculated using both radiopharmaceuticals, and were statistically compared using the paired samples t test. RESULTS: The excretion after furosemide injection was 25.3% +/- 18.2% for (99m)Tc-DTPA and 41.2% +/- 26.1% for (99m)Tc-EC, with a statistically significant difference between both radiopharmaceuticals (P <.0001). Using (99m)Tc-EC obstruction was excluded in 36 of 103 kidneys, which excreted >60%. A total of 10 of 83 kidneys (12.0%) with an obstructive pattern by (99m)Tc-DTPA study turned out to be indeterminate by (99m)Tc-EC DDRS. There was an agreement between (99m)Tc-EC and (99m)Tc-DTPA studies in 54 of 83 kidneys with obstructive (65.1%) and in 3 of 20 (15.0%) with indeterminate patterns. CONCLUSIONS: (99m)Tc-EC was more effective than (99m)Tc-DTPA for excluding obstruction, presenting less false-positive and indeterminate results. (99m)Tc-EC can substitute (99m)Tc-DTPA to evaluate patients with urinary tract dilation.

Cumulative doses of radioiodine in the treatment of differentiated thyroid carcinoma: knowing when to stop.

OBJECTIVE: Evaluate the efficacy of cumulative doses (CDs) of 131I-iodide therapy (RIT) in differentiated thyroid cancer (DTC). SUBJECTS AND METHODS: The probability of progressive disease according to CDs was evaluated in patients < 45 years old and > 45 years old and correlated to tumor-node-metastasis (TNM), thyroglobulin values, histological types and variants, age, and zduration of the disease. RESULTS: At the end of a follow-up period of 69 ± 56 months, 85 out of 150 DTC patients submitted to fixed doses RIT had no evidence of disease, 47 had stable disease and 18 had progressive disease. Higher CDs were used in the more aggressive variants (p < 0.0001), higher TNM stages (p < 0.0001), and follicular carcinomas (p = 0.0034). Probability of disease progression was higher with CDs > 600 mCi in patients > 45 years old and with CDs > 800 mCi in patients < 45 years. CONCLUSION: Although some patients may still respond to high CDs, the impact of further RIT should be carefully evaluated and other treatment strategies may be warranted.

Turner's syndrome and subclinical autoimmune thyroid disease: a two-year follow-up study.

Although autoimmune thyroid disease (AITD) is frequent in Turner's syndrome (TS), followup studies are scant, and there are none regarding subclinical thyroiditis. We investigated thyroid function and morphology in 17 patients with TS (mean age 14.6 years) with transient and asymptomatic variations of TSH and/or thyroid hormones. Our 2-year follow-up included measurements of TSH, free T4, T3 and TPO and Tg antibodies, ultrasound (US) (first and last evaluations) and scintigraphy (first evaluation). Thyroid volume was evaluated relative to the patients' stature. Fourteen had abnormal hormones, including four with hypothyroidism and one with hyperthyroidism, ten had positive antibodies, and all had abnormalities on US; uptake was normal in 14/16. Abnormal hormones were independent of antibodies, number of US findings, age, time of disease and volume. At the end of the follow-up, antibodies were associated with a high number of abnormal US features, particularly heterogeneous texture. Our results indicate that recurring thyroid hormone variations in TS are due to chronic AITD.

Esvaziamento gástrico nos pacientes com insuficiência renal crônica submetidos à hemodiálise / Gastric emptying study in patients with chronic renal failure on hemodialysis

RACIONAL: Queixas dispépticas são comuns em pacientes com insuficiência renal crônica. As mais frequentemente relatadas são anorexia, náusea, vômito, sensação de plenitude gástrica e dor epigástrica. A possibilidade destes sinais e sintomas estarem associadas ao retardo no esvaziamento gástrico é atraente. OBJETIVO: Estudar o esvaziamento gástrico de uma refeição sólida padronizada, em pacientes com insuficiência renal crônica em tratamento dialítico. MÉTODO: Foram estudados 31 pessoas de ambos os sexos com idade variável de 18 à 60 anos, sendo 14 com insuficiência renal crônica em hemodiálise há mais de 6 meses e 17 sadios. Foram excluídos pacientes com diabetes mellitus, amiloidose, doenças do colágeno, doenças dispépticas e/ou submetidos à operação gástrica, pacientes em uso de drogas pró-cinéticas gástricas e grávidas. O método do esvaziamento gástrico foi a cintilografia, através de câmara de cintilação de dois cabeçotes. A refeição teste padronizada consistiu de omelete de três ovos de galinha preparado com mistura de enxofre coloidal marcado com 185 MBq de tecnécio-99m. Foram estudados a curva de retenção gástrica total e o T½ do esvaziamento gástrico. Os testes estatísticos utilizados foram o de c2 e o de Kruskal Wallis. RESULTADOS: Os resultados confirmaram a homogeneidade dos grupos quanto à idade e o sexo. Não houve diferença estatisticamente significativa em relação às curvas de retenção gástrica total e o T½, semelhantes nos dois grupos. CONCLUSÃO: O esvaziamento gástrico de pacientes urêmicos em tratamento hemodialítico há mais de seis meses é igual ao de indivíduos sadios.

BACKGROUND: Dyspeptic symptoms are frequent in renal patients. They are anorexia, nausea, vomit, pain and epigastric distension. These symptoms can be related to the delay in gastric emptying. AIM: To investigate gastric emptying in patients with chronic renal failure on hemodialysis treatment. METHOD: Thirty one subjects (18-60 y) were studied, 14 on hemodialysis for at least 6 months and 17 healthy subjects). Patients with diabetes, amyloidosis, collagenous disease, pregnant, dyspeptic complaints , gastric surgery and patients taking procinetics drugs were excluded. Gastric emptying was investigated with radionuclide scintigraphy, using a dual-head scintillation camera. The standard test meal consisted of 185 MBq of technetium-99m sulfur colloid mixed with three scrambled eggs. For each study group a time-activity curve of gastric retention was generated and from that the T½ of gastric emptying was obtained. RESULTS: The groups were similar both in gender and age. There was no significant statistical difference in total retention curves between the two studied groups. Also the T½ of gastric emptying was similar in the two groups. CONCLUSION: Gastric emptying of patients on hemodialysis treatment for at least 6 months was not different from the health subjects.