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S Apter

Publications and source records attributed to S Apter.

At least 55 records · Page 3Linked to original sources
PubMed1997

Coronary calcium measurements by double helical computed tomography. Using the average instead of peak density algorithm improves reproducibility.

RATIONALE AND OBJECTIVES: Coronary calcium (CC) measured by fast computed tomography (CT) was proposed recently as a noninvasive method of monitoring the coronary atherosclerotic process. Assessment of the reproducibility of CC measurements (mainly interstudy variability) is essential for consistent interpretation of serial studies. METHODS: The authors scanned 74 patients (50 men and 24 women) twice on the same day to determine the interstudy variability of a new scoring algorithm, using the average instead of conventional peak CT density values. RESULTS: Nineteen patients had no calcium on either scan. In the remaining 55 patients, interstudy variability was decreased by 31% using the average algorithm (32%-23%; P < 0.001). CONCLUSIONS: Using the average instead of conventional peak density score provides better reproducible measurements of calcium by double helical CT.

Adult↗
PubMed1997

Coronary artery calcification in women with syndrome X: usefulness of double-helical CT for detection.

PURPOSE: To determine the usefulness of double-helical computed tomography (CT) for detection of diseased coronary arteries in women with anginal pain, positive exercise stress test results, and angiographically normal coronary arteries (syndrome X). MATERIALS AND METHODS: Double-helical CT of the coronary arteries was performed in 81 consecutive women who were referred for coronary angiography for evaluation of chest pain. Patients were classified into three groups according to stress test and angiographic results: normal (normal exercise test results and angiographically normal coronary arteries), syndrome X (abnormal exercise test results and angiographically normal coronary arteries), and coronary artery disease (at least one diseased vessel seen at angiography). RESULTS: The prevalence of coronary calcification in the syndrome X group was 63% (10 of 16 patients) compared with 96% (45 of 47 patients) in the coronary artery disease group (P = .002) and 22% (four of 18 patients) in the normal group (P = .02). The lowest total coronary calcification score and logarithmic transformed data were found in the normal group (2.9 +/- 0.7), statistically significantly higher values were found in the syndrome X group (4.3 +/- 1.5), and the highest values were found in the coronary artery disease group (5.1 +/- 2.0; for trend, P = .03). CONCLUSION: Double-helical CT may be useful in detection of atherosclerosis in women with syndrome X who demonstrate normal coronary arteries at angiography.

Calcinosis↗
PubMed1996

Absence of coronary calcification on double-helical CT scans: predictor of angiographically normal coronary arteries in elderly women?

PURPOSE: To test the hypothesis that angiographically normal coronary arteries in elderly women are identifiable by the absence of coronary calcification on double-helical computed tomographic (CT) scans. MATERIALS AND METHODS: Forty-eight consecutive women (age range, 60-76 years) underwent coronary angiography for chest pain evaluation, as well as double-helical CT. Thirty women (mean age, 65 years +/- 5) had coronary artery disease (CAD), defined as any angiographic disease, and 18 women (mean age, 66 years +/- 4) had angiographically normal coronary arteries. RESULTS: Women with angiographically normal coronary arteries had lower coronary calcification scores than those of patients with CAD: 5.7 +/- 11 versus 580 +/- 634, respectively (P = .0004). Seven women with angiographically normal coronary arteries demonstrated mild coronary calcification (score < 50). Of the 11 women without coronary calcification, none had CAD. Thus, the absence of coronary calcification on double-helical CT scans in elderly women was predictive of angiographically normal coronary arteries with 61% sensitivity, 100% specificity, and 85% accuracy. CONCLUSION: Double-helical CT is an accurate, noninvasive modality for diagnosing angiographically normal coronary arteries in elderly symptomatic women.

Aged↗
PubMed1996

Event-related potentials in schizotypal personality disorder.

This study examined whether abnormalities in event-related potentials (ERPs), reported in schizophrenia, extend to patients with schizotypal personality disorder (SPD). Auditory ERPs in an oddball paradigm were obtained in 19 SPD patients, 17 schizophrenic patients, and 20 normal control subjects (NCs). Schizophrenic patients had lower P300 amplitude than NCs; the P300 amplitude of SPD patients was intermediate, showing a linear trend but not a significant group difference. P200 amplitudes showed a similar trend. SPD patients had N100 and N200 amplitudes intermediate to schizophrenic patients and NCs, without significant group differences. Results suggest diminished P300 amplitude may not be as prominent in SPD as in schizophrenia. Studies with larger sample sizes, multiple lead assessment strategies, and more demanding tasks may further characterize ERP deficits in schizophrenia-spectrum disorders such as SPD.

Adult↗
PubMed1996

Radiation pneumonitis complicating mediastinal radiotherapy postpneumonectomy.

Radiation pneumonitis is a well-characterized clinicopathological syndrome. The severity of radiation-induced lung injury correlates, among other factors, with the extent of lung volume incorporated within the field of radiation. The present article describes the cases of two patients with radiation pneumonitis following pneumonectomy and mediastinal radiotherapy. Postpneumonectomy pulmonary-mediastinal shift of the remaining lung towards the operated side, with inclusion of lung parenchyma within the "mediastinal" radiation portals, resulted in a substantial (albeit clinically unsuspected) radiation pneumonitis. Chest computed tomography in the postpneumonectomy patient may be helpful to evaluate the degree of pulmonary-mediastinal shift and optimization of the radiotherapy field.

Combined Modality Therapy↗
PubMed1995

Lateral ventricular enlargement in schizotypal personality disorder.

Although an increase in the ratio of ventricular space to brain (ventricle-brain ratio), VBR) on computed tomography (CT) has been among the most robust findings in chronic schizophrenia, VBR has not been investigated in a large, well-characterized clinical population of patients with schizotypal personality disorder (SPD), a clinical entity with a phenomenologic, gentle biological, and treatment response relationship to chronic schizophrenia. Accordingly, CT scans were obtained in 36 male SPD patients, 23 males with other personality disorders, 133 male schizophrenic patients, and 42 male normal volunteers. The mean body of the lateral VBR was significantly greater in the SPD patients than in the patients with other personality disorders. The VBR of the SPD patients did not differ significantly from either that of the normal volunteers or the schizophrenic patients but was intermediate between the two groups. There were no correlations with either psychotic-like or deficit-related symptoms of SPD in either the SPD or total personality disorder cohorts. SPD patients, like schizophrenic patients, may have increased VBRs compared wit patients with other personality disorders; their VBRs fall between the means of schizophrenic patients and normal control subjects.

Adult↗
PubMed1995

Assessment of the central dopaminergic index of plasma HVA in schizophrenia.

Under fasting conditions, the dopamine (DA) metabolite homovanillic acid (HVA) in plasma originates mainly from central DA neurons or from central and peripheral noradrenergic (NA) neurons. The latter source contributes, in addition to HVA, the norepinephrine metabolites, for example, 3-methoxy-4-hydroxyphenylglycol (MHPG). It has been shown in primates that the association between HVA and MHPG in plasma or urine under varying rates of NA metabolism can be used to obtain an estimate of the central DA neuronal contribution of HVA to plasma or urine. This estimate is called the central dopaminergic index (CDI). Two studies presented here examine the applicability of this model in schizophrenia patients. The results were consistent with the proposed model and suggested that only about 30 percent of the total plasma HVA concentrations in our patients were derived from central DA neurons. A convenient modification of this model is proposed for future studies. Since the CDI of plasma HVA is not likely to be confounded by NA activity, this tool may prove useful in disentangling the roles played by the DA and NA systems in schizophrenia.

Brain↗
PubMed1995

Calcification of coronary arteries: detection and quantification with double-helix CT.

PURPOSE: To evaluate the accuracy of double-helix computed tomography (CT) in coronary artery calcification detection and quantification. MATERIALS AND METHODS: One hundred sixty patients with coronary disease (135 men, 25 women; age range, 45-62 years), of whom 138 had obstructive (stenosis of > 50% of diameter; n = 129) or mild (< 50% stenosis; n = 9) coronary artery disease (CAD) and 22 had normal coronary arteries (per angiographic findings), and 56 age-matched healthy control subjects underwent double-helix CT. RESULTS: Double-helix CT findings indicated that calcification was significantly more prevalent in patients with CAD (> 83%) than in patients with normal coronary arteries (27%) or in healthy control subjects (34%; P < .01). Sensitivity in detecting obstructive CAD was high (91%); however, specificity was low (52%) because of calcification in nonobstructive lesions. Comparison of double-helix CT and angiographic findings indicated that double-helix CT was 84% accurate with positive and negative predictive values of 89% and 59%, respectively. CONCLUSION: Double-helix CT is a useful noninvasive method for detection and quantification of coronary artery calcification.

Adult↗
PubMed1994

Total abdominal perfusion (TAP) in the treatment of abdominal metastatic melanoma.

Total abdominal perfusion (TAP) is a recently described technique in which the abdominal organs are isolated from the systemic circulation and perfused by means of an external pump. Administering chemotherapy into the circuit provides higher locoregional drug exposure with lower systemic toxicity. Two patients with melanoma metastatic to the abdomen were treated using this technique. The first patient suffered from intractable upper gastrointestinal bleeding due to unresectable melanoma metastasis of the duodenum. He underwent TAP with melphalan and cisplatinum. His bleeding stopped and the tumor regressed. The patient's response lasted for 6 months. The second patient had an unresectable liver metastasis. She underwent TAP with melphalan and DTIC, resulting in a complete response with disappearance of the liver mass, which lasted until her death in 13 months. Our conclusion is that TAP should be considered as a technique for regional chemotherapy, which may be used in the treatment of unresectable metastatic melanoma of the abdomen.

Abdominal Neoplasms↗
PubMed1994

Neuropsychological correlates of central monoamine function in chronic schizophrenia: relationship between CSF metabolites and cognitive function.

Schizophrenia is associated with multiple cognitive deficits which in turn may be related to abnormal dopamine (DA) function. To examine possible associations between cognitive dysfunction and central DA activity in schizophrenia, neuropsychological measures (visuospatial and verbal recall; performance on the Wisconsin Card Sort Test (WCST); visuospatial perception) were examined in 17 drug-free male schizophrenic patients and related to cerebrospinal fluid concentrations of the metabolites of dopamine (homovanillic acid (HVA)), serotonin, and norepinephrine. CSF HVA concentrations were correlated with the ability to recall visuospatial information, with attention to verbal tasks, and with WCST performance (low CSF HVA concentrations predicting poor performance on these tests) but not with the ability to recall verbally presented material and visuospatial perception. These data are consistent with earlier results suggesting that (cortical) DA function is associated with recall and retrieval of visuospatial information and with WCST performance.

Adult↗
PubMed1994

Symptomatic heterotopic splenic tissue in the left renal fossa.

Renal fossa heterotopic splenic tissue is characteristically asymptomatic and is usually an incidental finding that has been reported to mimic renal or adrenal tumors. However, symptoms related directly to the splenic tissue do occur. We present an unique case with simultaneous occurrence of an accessory spleen and splenosis which were diagnosed following intentional radiological investigations conducted to evaluate flank pain which was probably related to the presence of the heterotopic spleens. CT complemented by isotopic liver-spleen scan is the radiological modality of choice in the diagnosis of renal fossa splenosis. However, MRI may significantly contribute to the evaluation by accurate delineation of blood supply and surgical separation planes.

Adult↗
PubMed1993

Effect of neuroleptic medication on cerebrospinal fluid monoamine metabolite concentrations in schizophrenia. Serotonin-dopamine interactions as a target for treatment.

OBJECTIVE: This study examined the effect of neuroleptic treatment on indexes of dopamine and serotonin function in schizophrenic patients. We hypothesized that neuroleptic treatment would be effective by changing dopamine and serotonin function and/or by altering their interaction. DESIGN: Lumbar cerebrospinal fluid (CSF) concentrations of the metabolites of dopamine (homovanillic acid, [HVA]) and serotonin (5-hydroxyindoleacetic acid, [5-HIAA]) were measured after a minimum drug-free period of two weeks and again after five weeks of treatment with haloperidol, 20 mg/d orally. Psychiatric symptoms were rated within one day of CSF sampling. PATIENTS: Sixteen schizophrenic and three schizoaffective male inpatients. RESULTS: Neuroleptic treatment significantly raised HVA concentrations and significantly increased the ratio between HVA and 5-HIAA. The increase in HVA was not related to symptomatic improvement, whereas the increase in the HVA/5-HIAA ratio was significantly correlated with reduction in overall symptomatology. CONCLUSIONS: These findings suggest that the increase in HVA is relative to 5-HIAA, and not the absolute increase in HVA, that is related to symptomatic improvement. This, in turn, suggests that changing dopamine function relative to serotonin function, rather than changing dopamine per se, is associated with the therapeutic effect of haloperidol. Exploring serotonin-dopamine interactions in schizophrenia may be more informative than examining each system in isolation.

Adult↗
PubMed1993

Treatment with clozapine and its effect on plasma homovanillic acid and norepinephrine concentrations in schizophrenia.

Measurement of plasma concentrations of the dopamine metabolite, homovanillic acid (pHVA), is an indirect tool to assess changes in dopamine turnover. Levels of pHVA have been reported to decrease during treatment with conventional antidopaminergic, neuroleptics, with the decrement correlating with symptomatic improvement in schizophrenic symptoms. Clozapine, an atypical neuroleptic, is the only drug proved to be effective in treatment-refractory patients. However, the mechanism mediating this unique efficacy has not been fully elucidated. This study examined the effect of clozapine on pHVA concentrations in schizophrenic patients. Since clozapine potently binds to alpha 2-adrenergic receptors, plasma norepinephrine (pNE) concentrations were also measured. Twenty-eight treatment-refractory schizophrenic patients (24 men, 4 women) were treated with clozapine (up to 600 mg/day) for 5 weeks, after a minimum 1-week drug-free period. Symptomatology and pHVA and pNE concentrations were measured at the last drug-free day and weekly for 5 weeks. Fourteen patients responded to clozapine treatment, while an equal number did not. Mean pHVA concentrations did not significantly change during treatment with clozapine. Although clozapine tended to lower pHVA concentrations in treatment responders, the effect was small and not significant. Clozapine treatment significantly raised pNE concentrations, but this did not differentiate responders from nonresponders to clozapine. These findings suggest that clozapine's effect on DA turnover is small and that clozapine may be effective in treatment-refractory schizophrenia by mechanisms other than, or in addition to, dopamine receptor blockade. However, since about one-third of NE is metabolized into HVA, the clozapine-induced increase in pNE may have overshadowed a possible lowering effect of clozapine on pHVA.

Adult↗