Biomedical subjects
Publications and source records attributed to A Mateo Navarro.
Thyroid hemiagenesis is a very infrequent abnormality. We present a case of Graves disease associated to a congenital hemiagenesis of the thyroid gland. The thyroid scintigraphy, ultrasonography and laboratory analysis (that showed the existence of thyroid hyperfunction and the present of thyroid stimulating antibodies) were decisive in the diagnosis.
INTRODUCTION: The neuroblastoma (NB) is one of the most common pediatric malignant neoplasms. The most commonly used tumor markers in the diagnosis and follow-up of this tumor are the serum neuron-specific enolase (NSE), ferritin and lactic dehydrogenase and urinary vanillymandelic and homovanillic acid. The common imaging modalities are CT, MRI and 123I or 131I-meta-iodobenzylguanidine scintigraphy. AIM: The aim of this study is to assess the value of 123I-meta-iodobenzylguanidine (MIBG) scintigraphy and serum determinations of NSE and ferritin in the diagnosis and evolution of NB patients. MATERIAL AND METHODS: 20 patients (8 female, 12 male) whose ages ranged from 2 months to 9 years with a mean age of 2.64 years diagnosed of NB. 47 123I-MIBG scans, 47 NSE determinations and 47 ferritin ones were selected. RESULTS: At the time of diagnosis, 100% of the 123I-MIBG scans were positive. 65% of NSE determinations presented clearly pathological levels and 15% were very near to the cut-off point. Only 45% of the ferritin levels were increased. The differences between the lesions visible by 123I-MIBG scanning before and 3 months after treatment as well as NSE and ferritin levels were studied. When the Student's T test was applied, we found statistically significant pre and post-treatment differences in 123I-MIBG scanning and NSE. In the case of ferritin, there was no statistical significance in spite of the decrease in the values. The direct correlation and Spearman correlation between laboratory data and 123I-MIBG scanning as well as correlation between NSE and ferritin were also studied. There was a good correlation between 123I-MIBG and NSE and between NSE and ferritin. We have also studied the data in 7 relapses. CONCLUSIONS: 123I-MIBG scintigraphy and serum determination of NSE are two successful diagnostic tools for the diagnosis and evolution of NB patients.
Gastrinomas are uncommon tumors which are difficult to locate. They are often located in the head of the pancreas. About two-thirds of them are malignant, their growth is slow and they usually metastasize in the liver. In about 25% of cases, the Zollinger-Ellison (Z-E) syndrome is included in the multiple endocrine neoplasm type 1 syndrome (MEN 1).A 14-year old male patient presenting an episode of abdominal perforation which required emergency surgery is reported. The abdominal ultrasonography, CT scan and magnetic resonance revealed a single lesion in the left liver lobe, suggesting metastasis. Significantly increased levels of serum gastrin suggested a diagnosis of Z-E syndrome. A study with 111In-octreotide was required to locate the primary tumor and evaluate its extent. The scintigraphy showed only one abnormal uptake focus in the left liver lobe. Post-surgery scintigraphy studies revealed the presence of metastatic adenopathies which were removed after a second surgery. No pathologic findings were observed in the last nuclear medicine study. The somatostatin receptor scintigraphy is the most sensitive method to locate primary gastrinomas and to assess the tumoral dissemination in patients with Z-E Syndrome.
The case of a 60-year old woman first presented a rapidly growing left cervical mass is presented. The fine needle aspiration-puncture (FNAP) lead to a diagnosis of thyroiditis. Due to the persistence of the symptoms, the FNAP was repeated again but was not conclusive, so that a surgical biopsy was performed. The pathological diagnosis was diffuse large cell primary thyroid lymphoma (PTL). The PTL is a rare entity that accounts for less than 1% of all the Non-Hodgkin's lymphomas. The thyroid scintigraphy showed the existence of a cold nodule in the left thyroid lobule and the 67Ga scan revealed a large abnormal lesion in the mediastinum that extended to the right latero-cervical region. After two chemotherapy courses, the 67Ga scan was normal.
Determining the relationship of DMSA uptake of the left versus right kidney is theoretically one of the easiest quantitative procedures in nuclear medicine. The quantification can be performed on the posterior view, with or without a lateral view for correction of kidney depth. The geometric mean can also be determined by using both the anterior and the posterior views. This study has aimed to evaluate if there are significant differences in the quantification of the renal function percentage using only the posterior view and the geometric mean. Furthermore, we evaluated to what extent the patient's age and diagnosis influenced these differences. We have proposed a work protocol in which we indicate which cases the geometric mean should be calculated in order to minimize the possible errors occurring when only the posterior view is used.A total of 328 renal scintigraphies with 99mTc-DMSA performed at our Department in the last six months were studied. The mean and standard deviation of the differences as well as the correlation coefficient between both methods were calculated. The difference between the right renal function in posterior view and the right renal function obtained using the geometric mean was calculated for all the patients. The Student's T test was applied to determine whether the differences between both methods were statistically different from zero. Statistical differences were found in patients older than 9 years and in patients with genitourinary malformations.
Malignant fibrous histiocytoma (MFH) is the most common soft tissue malignant tumour in late adult life. MFH has been mentioned to have avid uptake of 67Ga citrate, and only 38% is uptake of 99mTc-MDP, although few cases of MFH have been reported. We present the case of a 73 years old male patient with MFH. In the blood pool phase of the bone scintigraphy, MFH was presented as an intense hyperactive lesion. In the late phase the tumor is one of the few MFH described to have avid uptake for 99mTc-MDP. In this work we also review some cases of MFH described and the different techniques used in the diagnosis and follow-up of these tumours.
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Simple or true thyroid cysts are very rare. We only have found one case in which colorless and acellular transparent fluid has been found by means of the fine needle aspiration puncture (FNAP). We report the case of a 33 year old female who first presented with a rapidly growing thyroid nodule. The thyroid scintigraphy revealed the existence of a cold nodule and the ultrasonography showed a lesion having a cystic appearance. The FNAP was performed and was both diagnostic and therapeutic in this case.
Acute cholecystitis is an uncommon disease in childhood. Few cases in patients under 10 years of age have been found in literature. An eight-year old male patient with no history of interest who had acute acalculous cholecystitis was reported. Ultrasonographic and isotopic studies led to the diagnosis and control of the patient's evolution.
INTRODUCTION: Retinoblastomas (RB) are the most common malignant intraocular tumors in childhood. The neuron specific enolase (NSE) is used as a tumor marker in different malignant diseases (mainly in neuroblastomas and lung carcinoma of small cells). In this work we report our experience using NSE and the role we consider that it plays in the determination of this enzyme in RB cases. MATERIALS AND METHODS: NSE determinations in aqueous humor (AH) and serum were carried out in 17 RB by means of a radioimmunometric assay and were compared with those values obtained in a control group composed of 8 subjects in whom the RB diagnosis as well as other diseases that could alter its determination had been ruled out. The possible correlation between NSE levels and different tumor stages (Reese-Elsworth and histological-clinical), as well as the tumor type (exophytic and mixed) were also studied. RESULTS: NSE levels were increased in AH and serum in 88% of RB patients and were normal in all the subjects in the control group (when a sample which was considered to be non-valid due to the presence of red cells in AH was excluded). No correlation between NSE levels in AH and serum and the different tumor stages was found. Nevertheless, the RB group of mixed tumor type showed a significantly higher mean in AH (p<0.01) than the RB exophytic group. CONCLUSION: NSE determination in AH is of value in the differential diagnosis in patients in whom RB is suspected but difficult to diagnose as well as in the diagnosis of relapses. Serum determinations are mainly useful in the follow-up and in the early diagnosis of possible metastases.
The case of a patient who came to the Nuclear Medicine Department for a bone scintigraphy to rule out bone metastasis because of a lung neoplasm is presented. Some days before, the patient had suffered a right brain infarction. 99mTc-MDP uptake could be seen in the infarction area. Different mechanisms of 99mTc phosphates deposition in tissues other than bones are reviewed in this article.
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OBJECTIVE: To ascertain whether a given level of antimyosin monoclonal antibody (AMA) uptake in the endomyocardial biopsy (EMB) can identify patients with rejection. MATERIAL AND METHOD: 186 examinations were performed on 65 patients (8 women and 57 men) with orthotopic heat transplant (HT): Mean age 51 +/- 13 years. There were 3 examinations per patient (range 1-6). The studies were conducted 13 to 880 days after the HT. The C/p uptake indexes were obtained according to the Carrió y cols. method and the results were compared with the biopsy findings. Rejection was considered to be when the biopsy showed at least one site of necrosis. RESULTS: 1) We analyzed the C/P index in accordance with the post-HT interval and with the degree of rejection obtained by EMB. No group showed any significant differences between the patients with an without rejection (p > 0,05). 2) We applied a variable threshold based on post-HT interval, using an exponential curve defined on the basis of the interval of the values corresponding to patients without rejection and good progress compared with that of the rejection patients. This approach also did not contribute any improvement compared to the use of a fixed threshold due to the significant overlay of the values for patients with and without rejection. 3) Finally, we analyzed the individual evolution of the C/P indexes for each patient in terms of time. In patients whose clinical progress was good, the C/P indexes were observed to drop progressively over time. In those whose clinical progress was poor, abrupt increases in the index values were observed. CONCLUSION: We were unable to differentiate significantly between patients with and without rejection in EMB using fixed and variable thresholds of the C/P index. However, the different patterns of evolution for each patient provide information on the lack of complications and could be used as a follow-up technique.
OBJECTIVES: The objective of this work has been to know if to all patients with diagnostic suspected of acute pulmonary embolism and pathologic perfusion scanning, ventilation scintigraphy were performed in the assistance context, analyzing etiopathogenic, clinic and diagnostic factors related with the non prescription of the ventilation scintigraphic study. METHODS: In 1992 we have carried out a retrospective and random study of 50 patients with perfusion scintigraphy for diagnostic suspected of acute pulmonary embolism (APE). RESULTS: A diagnosis of acute pulmonary embolism and deep vein thrombosis was made respectively in 35 (70%) and 22 (44%) of a total of 50 patients. In twenty patients ventilation scintigraphic study were not performed, six of them with normal perfusion scanning and fourteen patients with pathologic scintigraphic perfusion and acute pulmonary embolism diagnosis (78.5% with high probability scintigraphic scans). In this work we find a total of 14 patients with perfusion scanning without ventilation study. The presence of high probability scintigraphic scans or the acute pulmonary embolism were significant statistically related with the non prescription of the ventilation study. CONCLUSIONS: In our opinion, none of these factors can explain the non realization of the ventilation scanning, considering this study indispensable before the presence of patient with scintigraphic perfusion defects and suspected of pulmonary embolus.
The case of a patient who had undergone surgery for papillary carcinoma of the thyroid is reported. After administering a therapeutic 131I capsule, the radionuclide scan showed a diffuse, "halo-like" thoracic uptake in the precordial region. The patient's normal thyroglobulin levels and the characteristics of radionuclide uptake did not suggest metastasis. Chest radiography and ultrasonography identified pericardial effusion, which was attributed to hypothyroidism.
99MTc is an ideal nuclide for Pediatric use. Combined with DTPA is an adequate agent for renal studies. 15 patients with ages ranging from eight days to eleven years were studied (10 patients with congenital malformation and five with renal tumour). The dosimetric advantages, the obtention with a single nuclide dose of multiple images and the diagnostic usefulness in congenital malformation and renal tumour suggest their use.
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