Immunoscintigraphy with 131I or 111In Labelled OC 125 F(ab')2 Fragments in Patients with Ovarian Carcinoma

To evaluate the clinical usefulness of immunoscintigraphy with OC 125 in ovarian carcinoma, we studied 25 patients suspected of having ovarian carcinoma or in follow-up after surgery. Fourteen patients were studied with 131I-OC 125 F(ab')2 and 11 with 111In-OC 125 F(ab')2. No differences were observed with the use of either radionuclide.

Global diagnostic indexes obtained were S = 100%, Sp = 44,5% and A = 81%. The low specificity obtained was remarkable: 5 false positive results in two uterine myomas, one abscess, one follicular cyst and one granulation tissue scar. On the other hand, all lesions of ovarian carcinoma were detected. Analysis of the evolution of tumor/background (T/B) uptake ratios from the first to the second day of exploration revealed a tendency for the ratio to diminish significantly (> 15%) in false positive cases with the exception of the abscess while this did not happen in true positive cases, with the exception of a regional recurrence. Analysis of T/B ratio variations could contribute towards elevating the test's specificity.

Monounsaturated fat-rich diet prevents central body fat distribution and decreases postprandial adiponectin expression induced by a carbohydrate-rich diet in insulin-resistant subjects

OBJECTIVE

Central obesity is associated with insulin resistance through factors that are not fully understood. We studied the effects of three different isocaloric diets on body fat distribution, insulin sensitivity, and peripheral adiponectin gene expression.

RESEARCH DESIGN AND METHODS

Eleven volunteers, offspring of obese type 2 diabetic patients with abdominal fat deposition, were studied. These subjects were considered insulin resistant as indicated by Matsuda index values <4 after an oral glucose tolerance test, and they maintained A1C <6.5% without therapeutic intervention. All subjects underwent three dietary periods of 28 days each in a crossover design: 1) diet enriched in saturated fat (SAT), 2) diet rich in monounsaturated fat (MUFA) (Mediterranean diet), and 3) diet rich in carbohydrates (CHOs).

RESULTS

Weight, body composition, and resting energy expenditure remained unchanged during the three sequential dietary periods. Using dual-energy X-ray absorptiometry we observed that when patients were fed a CHO-enriched diet, their fat mass was redistributed toward the abdominal depot, whereas periphery fat accumulation decreased compared with isocaloric MUFA-rich and high-SAT diets (ANOVA P < 0.05). Changes in fat deposition were associated with decreased postprandial mRNA adiponectin levels in peripheral adipose tissue and lower insulin sensitivity index values from a frequently sampled insulin-assisted intravenous glucose tolerance test in patients fed a CHO-rich diet compared with a MUFA-rich diet (ANOVA P < 0.05).

CONCLUSIONS

An isocaloric MUFA-rich diet prevents central fat redistribution and the postprandial decrease in peripheral adiponectin gene expression and insulin resistance induced by a CHO-rich diet in insulin-resistant subjects.

Cerebrospinal fluid S-100 protein levels in neurological pathologies

The aim of this paper was to evaluate S-100 concentration in cerebrospinal fluid (CSF) from patients with different neurological disorders, and in subjects with no proven neurological pathology, in order to study possible differences in their protein concentrations. The total number of patient-samples examined was 119 (58 males and 61 females; mean age 35 yrs, 1-79 yrs). Based on the final diagnoses, nine patient groups were studied: a control group, meningitis, acute lymphatic leukemia (ALL), dementia, hydrocephalia, polyneuropathy-motor neuron disease, acute cerebral infarction (ACI), and patients diagnosed with multiple sclerosis. S-100 protein concentrations were measured by the Sangtec 100 two-site immunoradiometric assay. The highest S-100 levels in CSF were found in the dementia group, ACI group, bacterial-fungal and lymphocytic meningitis groups (Kruskal-Wallis test). The S-100 concentrations in these groups were significantly higher compared with the control group (Mann-Whitney U test, p<0.05, p<0.01) and the multiple sclerosis group (p<0.05, p<0.01). No other significant differences were found between groups. Our results suggest that the high protein levels in CSF found in these pathologies may reflect the presence of brain damage. However, the levels need to be considered individually, as they depend on several factors, such as age, severity of brain damage or interval between the onset of brain damage and the taking of the sample.

[Level of S-100 and neuron-specific enolase in cerebrospinal fluid from subjects with neurological pathologies]

AIM

To evaluate S-100 and neuro specific enolase (NSE) levels in cerebrospinal fluid (CSF) from patients with differents neurological disorders in order to study possible differences in their protein concentrations.

MATERIAL AND METHODS

We analysed samples of CSF taked by spinal puncture in subjects either from of the Casualty Department or from the Department of Neurology. Patients displaying neurological symptoms capable of being diagnostically tested. The total number of patients-samples examined was 43 (23 males and 20 females; mean age 43 y, range 1-78 y). Five patients groups were studied: a control group, meningitis, dementia, polyneuropathy-motorneuron disease, and acute cerebral infarction group (ACV). S-100 and NSE concentrations were measured by immunoradiometric procedures.

RESULTS

Highest S-100 median levels in CSF were found in dementia and ACV group, with elevate concentrations in meningitis groups. The increased S-100 levels in these groups was significant compared with control group (Mann-Withney U test). For NSE concentrations, there is a significant differences between dementia group and control group. No other significant differences were found between groups. There were positive correlation between S-100 levels and total protein.

CONCLUSION

Our results suggest that S-100 and NSE can be a sensitive marker of brain damage in different neurological disorders. However, levels must be considered individually, since these concentrations depend on several factors, such as age, severity of brain damage or interval between the onset of brain damage and the taking of the sample.

[Pulmonary activity in sarcoidosis: 67Ga uptake quantification and plasma determination of 1,25-dihydroxyvitamin D)]

AIM

The aim of our study was to produce a quantitative determination of Ga-67 pulmonary intake and correlate it with plasma levels of calcitriol.

MATERIAL AND METHODS

A prospective study was conducted, and included 65 patients (29 female, 36 male) referred to our section due to suspected sarcoidosis or fibrosis of the lungs. Gammagraphic images were obtained after injecting Ga-67 citrate, and vitamin D was determined by IRMA method. The final diagnosis led to 4 groups of patients: 26 with active sarcoidosis; 5 with inactive sarcoidosis (4 with a previous gammagraphic study, included in the previous group); 8 with fibrosis of the lungs; and 30 patients with no demonstrable pathology following medical/instrumental examination. For the quantitative analysis, areas of interest were drawn around each lung, together with another region in soft tissue of the right shoulder (background). The geometric mean for each region was calculated, as well as the Ga intake rate (InGa = [lung activity-background]/background).

RESULTS

Significant differences were found (p<0.01) when comparing each group's InGa, with the highest values occurring in the active sarcoidosis group. No significant differences were found when comparing plasma levels of calcitriol. No significant correlation was demonstrated between hormone and InGa rates.

CONCLUSIONS

InGa would seem to be a useful parameter for assessing inflammatory activity in the parenchyma of the lungs. Perhaps as a result of their variability, plasma concentrations of the active vitamin D metabolite have a limited role in this assessment.

[Effect of different observers on the interpretation of pulmonary perfusion scintigraphy]

AIM

The agreement in the interpretation of the scintigraphic images of pulmonary perfusion in the diagnosis of pulmonary tromboembolism (TEP) is not always the most adequate. The purpose of this study was to evaluate the degree of agreement by eight observers in the interpretation of these studies.

MATERIAL AND METHODS

The study population consisted of 180 studies with clinically suspected pulmonary embolism referred to our department for scintigraphic perfusion imaging from April 98 to September 99. The patients received an intravenous injection of 111-148 MBq (3-4 mCi) of 99mTc-macroaggregated albumin whereas the images were obtained in the six routine projections. The observers consisted of five nuclear medicine physicians and three residents who independently reviewed the scintigrams (low, intermediate and high probability). In a second step, the physicians performed consensus interpretations. The Kappa statistics was used to evaluate the degree of agreement between individual observer interpretations beyond that expected by chance alone.

RESULTS

The mean value SEM for Kappa index was 0.58 0.02, with maximum and minimum values of 0.76 and 0.27 respectively. The interobserver variability was greater than expected. Except in two observers scans in the interpretation of images in the low and high categories showed minor discrepancies, whereas scans in intermediate probability showed the most important interobserver variations.

CONCLUSION

The study manifests the importance of a uniform criteria in lung scintigraphic interpretation.

[Tomographic studies of myocardial perfusion normality with 99m Tc-Tetrofosmin. Spanish multicenter study]

As a first phase in a nationwide multicenter study to obtain myocardial perfusion normality patterns, this work presents the study design and quality control methodology used to guarantee that the gammacameras fulfilled some minimum quality requirements. The following aspects were considered in the study design in order to guarantee the homogeneity and interchangeability of the results: creation and structure of the work group, data interchange system, data selection and acquisition, centralized archiving and processing, assessment system, study acceptance criteria and distribution of the results. To carry out the instrumental quality control, three phantom studies were established, one to control the rotation center, another to verify tomographic uniformity and a third to simulate the shape and orientation of the left ventricle. The three phantoms circulated through all of the 18 participating centers in this project, which corresponded to 19 gammacameras. Very strict guidelines had to be followed in the acquisition and processing of these phantom studies. If any camera and/or center did not fulfill the criteria established, it was advised of the problem detected in order to correct it. Once the defect was repaired, all the phantoms were sent again for verification. Uniformity of the rotation center was quantified by means of the eccentricity of a 360 degrees orbit, admitting up to a maximum of 10%. Tomographic uniformity was visually assessed, taking in account the number of slices with rings and their contrast and finally no artifacts could be present in the reconstructed study of the ventricle. The center of rotation was within limits in all the cameras except one case while the tomographic uniformity was incorrect in 6 cases. All the departments, except one, corrected the defects detected, and passed the acceptance test. The results made it possible to guarantee adequate homogeneity and instrumental quality in this multicenter study.

Catecholamine levels in practitioners of the transcendental meditation technique

With the aim of evaluating the sympathetic-adrenal medulla system in subjects practicing transcendental meditation (TM), their plasma catecholamine levels were determined at two different times of day. The study group consisted of 19 subjects who regularly practice either TM or Sidhi-TM technique, with a control group made up of 16 healthy subjects who had not previously used any relaxation technique. Catecholamine plasma levels were determined by high performance liquid chromatography, at 0900 and 2000 h. Morning and evening norepinephrine (NE) levels and morning epinephrine (E) levels were significantly lower in the TM group than in the control subjects (morning NE levels, pg/ml, mean+/-S.E.: TM group 136.6+/-13.0, control 236.8+/-21.0, P=.0001; evening NE levels: TM group 119.7+/-10.8, control 175.6+/-17.4, P=.009; morning E levels, pg/ml: TM group 140.2+/-10.6, control 196.7+/-23.8, P=.019). No differences were recorded for evening E levels and dopamine (DA) levels. No significant differences were found for catecholamine levels measured at different times of day in the TM group, demonstrating a lack of daily hormonal rhythm. Anxiety levels were similar in both groups. Based on the results obtained, it can be considered that the regular practice of TM has a significant effect on the sympathetic-adrenal medulla system. A low hormonal response to daily stress caused by sympathetic tone regulation through regular TM could explain our results, as well as the physiological and other effects related to the field of health described in those who practice meditation.

[Scintigraphic pattern in a case of Tarlov cyst]

We report the case of a 40-year-old man remitted to our department with a history of lower back pain and sciatica with no history of trauma. The laboratory analyses showed normal values whereas plain radiographs showed a sacrum rarefaction area. A 99mTc-MDP bone scintigraphy was performed to evaluate the lumbosacral area. Planar images did not show any abnormality. SPECT images revealed photopenic abnormality in the second sacral vertebral right hemibody, with no peripherally increased radiotracer accumulation. Subsequent MRI and CT myelography demonstrated the nature of the photopenic area as secondary to vertebral erosion by sacral perineurial cyst (Tarlov cyst).

Evaluation of tumor marker S-100 in cerebrospinal fluid from subjects with nonischemic brain pathologies

In order to evaluate the S-100 concentration in cerebrospinal fluid from subjects with nonischemic brain damage, a total of 33 samples were analyzed: 11 from subjects in whom no organic disease could be found; 14 from patients with a diagnosis of lymphocytic or bacterial-fungal meningitis, and 8 from patients with acute lymphatic leukemia but no demonstrable signs of meningeal involvement. In all cases, the subjects considered had no previous history of melanoma or ischemic brain damage. The mean levels +/- SEM found for each study group were 1.00 +/- 0.11, 1.67 +/- 0.23 and 1.17 +/- 0.14 microg/l, respectively. Significant differences appeared between the groups when applying the Kruskal-Wallis nonparametric test (p = 0.035). The highest levels were found in the meningitis group and were significantly different from those of the control group (p = 0.015). No significant differences were found with regard to age or sex. Based on the pathophysiology of meningitis and on previous studies, the results suggest the existence of brain damage caused by an infection as a possible cause of increased S-100 levels.

Repetitive nontreated episodes of grade 1B or 2 acute rejection impair long-term cardiac graft function

BACKGROUND

Episodes of grade 1B or 2 acute heart rejection are usually not treated, and most of them resolve spontaneously.

METHODS

With the aim to assess long-term outcome in patients with repetitive nontreated episodes of low-grade (1B, 2) acute rejection, we have studied 141 heart transplant recipients in whom the evolutive pattern of acute rejection during the first 6 months after transplantation could be determined.

RESULTS

Forty-four patients (31%) had only grade 0 or 1A acute rejection episodes (pattern A); 23 patients (16%) had three or more episodes of grade 1B or 2 acute rejection without 3A or more advanced rejection (pattern B); 48 patients (34%) had one or two episodes of grade 3A, 3B, or 4 acute rejection only during the first 6 months after transplantation (pattern C); and 26 patients (19%) had three or more episodes of grade 3A, 3B, or 4 acute rejection (pattern D). Overall mortality was 11%, 26%, 19%, and 46% for patients with patterns A, B, C, and D, respectively. No difference was found among patterns with regard to incidence of graft atherosclerosis. Left ventricular ejection fraction at 1 year after transplantation was significantly lower (p < 0.05) for patients with pattern B (50% +/- 5% versus 59% +/- 7%, 59% +/- 11%, and 56% +/- 6% for patterns A, C, and D, respectively); cardiac index also was lower for patients with pattern B than for those with pattern A (3.6 +/- 0.6 versus 4.1 +/- 0.6 L/min/m2, p < 0.05).

CONCLUSIONS

Although mortality was higher for patients with more severe episodes of acute rejection, only repetitive nontreated episodes of grade 1B or 2 rejection significantly impaired long-term graft function.

[Short- and long-term course of heart transplantation recipients with severe dysfunction of the graft associated with acute rejection]

INTRODUCTION AND OBJECTIVES

Acute rejection is still a common cause of death after heart transplantation, in spite of cyclosporine. The aim of our study was to assess the incidence of severe graft dysfunction associated with acute rejection and the short and long-term outcome of these patients.

METHODS

Ten of our 100 first heart transplant patients have developed rejection-induced severe cardiac dysfunction (left ventricular ejection fraction determined by echocardiography < 35% associated with 3A, 3B or 4 acute rejection). Clinical outcome, complications and evolution of left ventricular function were studied.

RESULTS

Five patients were given intravenous methylprednisolone 500 to 1000 mg/day for 3 days. The other 5 patients had severe heart failure and received antilymphocyte antibodies. Three patients treated with methylprednisolone alone and one patient treated with antilymphocyte antibodies died within the first week after therapy. Left ventricular ejection fraction increased from 26 +/- 4% to 51 +/- 6% at 1 month after therapy in the 6 survivor patients. Four of the 6 survivor patients also died before 1 year after rejection (3 due to infection). Thus, long-term, overall mortality was 80%.

CONCLUSIONS

Although favorable short-term results can be achieved in patients with rejection-induced severe cardiac dysfunction with immunosuppressive therapy (mainly antilymphocyte antibodies), long-term prognosis seems poor, due to the increased rate of life-threatening infections.

Influence of heart transplantation on the natural history of patients with severe congestive heart failure

In an attempt to study the influence of heart transplantation on the natural history of patients with severe congestive heart failure, we have reviewed our experience with 240 consecutive patients who were New York Heart Association class IV or III/IV, who had left ventricular ejection fraction less than 35%, who were younger than 65 years of age, and who were assessed for heart transplantation in our hospital since May 1986. Mean age was 47 +/- 12 years. Left ventricular ejection fraction was 20% +/- 6%. Eighty-seven percent were male. New York Heart Association class was IV in 88% and III/IV in 12%. The cause was ischemic heart disease in 35% of patients, valvular heart disease in 13% of patients, and primary dilated cardiomyopathy in 52% of patients. At initial assessment, heart transplantation was considered to be not indicated in 30% of patients, indicated in 51% of patients, and contraindicated in 19% of patients. During a follow-up of 13 +/- 13 months (2 to 64 months), 110 patients underwent transplantation (46%). Posttransplantation actuarial probability of survival was 70% at 3 years. Three-year probability of survival free from transplantation was significantly lower for patients older than 55 years of age (p < 0.05), for those with left ventricular ejection fraction less than 20% (p < 0.05), ischemic causes (p < 0.05), New York Heart Association class IV (p < 0.001), and indication/contraindication for transplantation (p < 0.001); no difference was noted for gender.(ABSTRACT TRUNCATED AT 250 WORDS)

Clinical and hemodynamic predictors of survival in patients aged < 65 years with severe congestive heart failure secondary to ischemic or nonischemic dilated cardiomyopathy

To identify which clinical or hemodynamic parameters predict survival in patients with end-stage heart failure due to dilated cardiomyopathy, 130 consecutive patients aged < 65 years (mean 46 +/- 13) assessed for heart transplantation from May 1986 to April 1991 were studied. Mean follow-up was 15 +/- 11 months. Left ventricular ejection fraction was 22 +/- 7%. Left ventricular end-diastolic pressure was 27 +/- 9 mm Hg, and cardiac index was 2.2 +/- 0.6 liter/min/m2. Symptom class was IV in 91% of patients and III in 9%. Etiology was ischemic in 40% of patients and idiopathic in 60%. After intensive medical therapy, heart transplantation was considered indicated in 53% of patients, contraindicated in 20% and not indicated in 27%. Transplantation was performed in 36% of patients during follow-up, and 35% died and 29% were alive without transplantation. A comparison, excluding patients with transplantation, was performed between those who were alive and had survived > or = 6 months after assessment, and those who died. On multivariate analysis, the following 3 parameters were independent predictors of prognosis: intravenous inotropic requirement (p < 0.001), maximal, tolerated captopril dose (p = 0.013) and systolic blood pressure (p = 0.003). When patients with transplantation were considered as deaths, stabilization on medical therapy also reached statistical significance (p = 0.009). Classic prognostic markers including ventricular arrhythmias, left ventricular end-diastolic pressure, cardiac index, amiodarone therapy and etiology were not associated with prognosis in this homogeneous population of severely ill patients.

Preliminary experience with deflazacort, a new synthetic steroid with fewer undesirable side effects, in heart transplant patients

Prednisone is widely used by most heart transplant units, despite its frequent side effects. Deflazacort, a new oral synthetic steroid with fewer side effects, has not been studied in heart transplant patients. Our initial experience with 26 heart transplant patients in whom prednisone was replaced by deflazacort at 11 +/- 11 months after transplantation is reported. After the switch to deflazacort, a significant decreased was noted in glycemia, total cholesterol, and LDL-cholesterol (p < 0.001). No difference was noted in severity or frequency of rejection and infection between patients being treated with deflazacort and another 26 patients who continued to be treated with prednisone over a comparable period of time after transplantation.

Myocardial damage following coronary bypass surgery: assessment with antimyosin antibody uptake

To assess the role of 111In antimyosin antibody (AbAm) in the delineation of myocardial damage following coronary bypass surgery, we studied 51 consecutive patients who underwent coronary surgery, 27 of whom had a history of prior myocardial infarction. All patients underwent a diagnostic protocol comprising: (1) 99Tcm pyrophosphate (PYP) and AbAm injection 48 h after surgery (AbAm imaging 24 and 48 h post-injection) (myocardial/background and myocardial/lung ratios were obtained respectively from the computer image); (2) Radioimmunoassay (RIA) serum CK-B levels from samples obtained immediately before surgery, and 24 and 48 h later; (3) clinical and ECG follow-up. Twenty-five patients showed positive AbAm studies, 10 had positive PYP images, and 21 had CK-B levels above normal limits at 24 h. One patient with abnormal AbAm, PYP and CK-B studies had new Q waves on the ECG after surgery. This patient was considered to have sustained a peri-operative myocardial infarction. The large number of positive AbAm studies probably reflects myocardial damage frequently associated with coronary bypass surgery.

Influence on survival after heart transplantation of contraindications seen in transplant recipients

Fifty-seven patients underwent heart transplantation at our hospital between April 1986 and April 1991. In an attempt to assess the result of and the influence of contraindications seen in transplant recipients before transplantation on the outcome after transplantation, we have analyzed six of these "relative" contraindications: (1) age over 55 years (21% of patients); (2) pulmonary hypertension (pulmonary vascular resistance of more than 5 Wood units, and/or transpulmonary gradient of more than 12 mm Hg; 26% of patients); (3) renal failure (serum creatinine level of more than 2 mg/dl, and/or creatinine clearance of less than 35 ml/min; 11% of patients); (4) active infection (9% of patients); (5) diabetes mellitus (7% of patients); and (6) critical/unstable clinical condition before transplantation (25% of patients). An overall "risk score," obtained by adding one point for each contraindication, was also analyzed. Risk score was 0 (the "ideal" recipient) in 38% of patients, 1 in 25% of patients; 2 in 23% of patients; and 3 or more in 14% of patients. Actuarial survival was significantly lower for patients over 55 years of age (45% versus 68% at 18 months; p less than 0.05), for patients with elevated pulmonary vascular resistance (38% versus 72%; p less than 0.01), and for patients with kidney failure (16% versus 70%; p less than 0.01). On the contrary, survival at 18 months was not significantly different for patients with or without diabetes mellitus (50% versus 63%; not significant [NS]), active infection (60% versus 63%; NS), or critical/unstable condition (45% versus 69%; p less than 0.1).(ABSTRACT TRUNCATED AT 250 WORDS)

Noninvasive radioisotopic diagnosis of acute heart rejection

In a prospective protocol for noninvasive diagnosis and follow-up of acute heart rejection 162 examinations were performed in 36 patients who underwent heart transplantation. The follow-up period ranged from 15 days to 44 months. The protocol comprised multiple gated acquisition ventriculography with albumin labeled with 99mTc (740 MBq), acquired using a forward/backward by thirds framing mode, 32 frames/cycle, and 10 million total counts. Parameters of left ventricular diastolic function were analyzed. Antimyosin antibody labeled with indium 111 (74 MBq) was injected, and myocardium/lung uptake ratios were obtained at 48 hours in counts per pixel. Endomyocardial biopsy was performed in all patients within 48 hours. The results were evaluated by comparison of mean values of each parameter and global and individual correlation analysis in relation to the presence or absence of rejection and treatable (moderate or severe) or nontreatable (mild or absent) rejection. Antimyosin and diastolic function parameters showed significant differences (p less than 0.001) between patients with and without rejection and between patients with treatable and nontreatable rejection. Global correlation with biopsy existed (p less than 0.05) for antimyosin (r = 0.75), average filling rate (r = 0.61), and peak filling rate (r = 0.56). Individual correlation exhibited significance in all patients only for antimyosin (r = 0.78 to 0.98). In eight patients average filling rate also showed significant correlation (r = 0.65 to 0.88). In conclusion, these results provide a noninvasive diagnosis of cardiac allograft rejection episodes and allow an accurate selection between treatable and nontreatable rejection. Individual patient follow-up is possible with antimyosin. The study of diastolic function is also useful in this setting.

Diagnosis of brain death: superiority of perfusion studies with 99Tcm-HMPAO over conventional radionuclide cerebral angiography

The use of technetium-99m hexamethyl-propyleneamine oxime (99Tcm-HMPAO) in the diagnosis of brain death has been evaluated in 41 studies of 37 patients with severe brain injury, who were under the effect of drugs or when other diagnostic methods were equivocal. HMPAO studies were compared with conventional radionuclide angiography performed simultaneously by intravenous administration of HMPAO as a bolus. The ages of patients ranged from 4 months to 75 years. Dynamic flow images and 5-min static uptake images were acquired following bolus injection of 555 Mbq of 99Tcm-HMPAO. All patients showing no brain uptake were confirmed as brain-dead by standard clinical criteria, with no contradictory cases in the static study. In addition, all patients who were not brain-dead showed HMPAO uptake at least in the brainstem. Dynamic flow images were equivocal in five patients, four of whom had no uptake on static images and clinically confirmed brain death. In addition, two other cases showed "mismatched" dynamic and static images: in one case no perfusion was observed on flow images but uptake restricted to the posterior fossa was seen on static images; the other case showed perfusion on the dynamic study and static imaging revealed hemispheric uptake with no posterior fossa uptake. Static perfusion 99Tcm-HMPAO studies offer advantages over conventional brain scintigraphy, better results being due to adequate assessment of posterior fossa activity and avoiding equivocal studies.

Immunoscintigraphy of lung cancer using 111In-labelled antiCEA F023C5-F(ab')2 fragments

Forty-one patients with known lung carcinoma or suspicion of bearing this disease were studied with 111In-antiCEA F023C5-F(ab')2. Five patients with positive results were further studied to assess in vivo specificity using 111In-4C4-F(ab')2 (MoAb antihepatitis). Immunoscintigraphic results have been compared to immunohistochemistry in 16 patients. Tumour visualization with non-specific MoAb was present in all five patients although the maximum tumour/background (T/B) ratio obtained was 1.51. Therefore a 'specificity criterion' has been applied to examinations performed with MoAb antiCEA. There was considered to be a positive result when the T/B ratio was greater than 1.60. Results obtained in this way for thoracic lesions were 25/34 true positive (TP) (73%) and 6/7 true negative (TN) (86%). When studies were analysed visually only, the results were 32/34 TP (94%) and 3/7 TN (43%). In addition, immunoscintigraphic results are more concordant with immunohistochemical results when the specificity criterion is applied. In metastatic lesions results were 9/13 TP (69%) with only 1/3 TP (33%) for liver metastasis (anatomic site of lowest detection ability). SPECT imaging did not improve results over planar images, although it clearly contributed to a better anatomic location of lesions. The constant presence of non-specific uptake in thoracic lesions makes it necessary to establish a T/B ratio limit in order to obtain adequate specificity with the immunoscintigraphic technique.

[Infarct size determination using enzymatic methods in patients with early coronary recanalization]

To evaluate the usefulness of the infarct size determined by serial creatine kinase (CPK) measurements in patients with early reperfusion, we have studied 189 patients meaning in age 59.2 +/- 8.6 years, with acute myocardial infarction treated with streptokinase (STK); 81 of them by intracoronary route (group A), and 108 by intravenous administration (group B). In the group A we performed serial angiographic studies in the following conditions: baseline, immediately after STK infusion and before hospital discharge. In group B we performed only one angiographic control 5 +/- 3 days after. In patients with reperfusion, the parameters of left ventricular function correlated with cumulative creatine kinase release (MAX-CPKr) by linear regression in both groups. We observed a tendency to closer correlations in patients with left anterior descending or circumflex artery as the infarct related artery, in patients without previous infarction and in those who did not receive electrical shock for ventricular arrhythmias. In patients with unsuccessful reperfusion (n = 11), we also obtain a significant correlation (r = 0.72) between ejection fraction and MAX-CPKr. The slope of the regression line (b = 7.7 X 10(-5) was steeper (p less than 0.05) than that observed in recanalized patients, who were evaluated within the first 3 days (b = 2.2 X 10(-5), after 8 +/- 5 days (b = 2.7 X 10(-5), or before discharge, at 22 +/- 9 days (b = 2.6 X 10(-5).(ABSTRACT TRUNCATED AT 250 WORDS)

[Transaxial tomography in the study of myocardial perfusion with thallium-201]

Stress and redistribution thallium-201 myocardial imaging using a transaxial single emission computed tomographic system has been applied to the diagnosis of coronary artery disease. Data sampling was performed along a limited 180 degree arc, obtaining 32 images in a continuous mode, at a rate of 20 seconds per image. The production of perfusion defects in patients was stimulated by exercise testing or by dipyridamole infusion. No significant differences existed when both tests were compared (p less than 0.01). Normal and abnormal patterns including the different pathophysiological alterations of myocardial ischemia were defined in three tomographic planes using this methodology. Patients with coronary disease are separated from patients without coronary disease with high probability (84%). Transaxial SPECT (single photon emission computerized tomography) provides a significant increment in sensitivity and specificity in relation to planar scintigraphy in the detection of myocardial infarction (91 and 100%, respectively); residual ischemia postinfarction (96 and 97%, respectively), and significant coronary artery disease (91 and 97%, respectively).