Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 67
Filter
1.
Biol Psychiatry ; 38(8): 516-24, 1995 Oct 15.
Article in English | MEDLINE | ID: mdl-8562663

ABSTRACT

Minor physical anomalies, together with obstetric complications, family history, and handedness status, were assessed to explore putative neurodevelopmental disturbance(s) in patients with schizophrenia whose cerebral structure had been examined previously by magnetic resonance imaging. Minor physical anomalies were related to negative symptoms in males and to premorbid intellectual function in females, but not to ventricular volume; however, three patients with evident neurodevelopmental anomalies of the ventricular system showed prominent minor physical anomalies. In exploratory analyses, obstetric complications were associated with left ventricular asymmetry, and a positive family history with inverse profiles of asymmetry in males vs. females; non-right-handedness was associated with increased ventricular volume in males but with poorer premorbid intellectual function in females. This nexus of relationships and their gender specificities suggest early dysmorphogenesis in schizophrenia that is related to sexual dimorphism.


Subject(s)
Abnormalities, Multiple/diagnosis , Brain/abnormalities , Developmental Disabilities/diagnosis , Magnetic Resonance Imaging , Neurocognitive Disorders/diagnosis , Schizophrenia/diagnosis , Schizophrenic Psychology , Abnormalities, Multiple/genetics , Abnormalities, Multiple/psychology , Adult , Aged , Brain/pathology , Cerebral Ventricles/pathology , Developmental Disabilities/genetics , Developmental Disabilities/psychology , Dominance, Cerebral/genetics , Dominance, Cerebral/physiology , Female , Humans , Infant, Newborn , Intelligence/genetics , Intelligence/physiology , Male , Middle Aged , Neurocognitive Disorders/genetics , Neurocognitive Disorders/psychology , Pregnancy , Prenatal Exposure Delayed Effects , Schizophrenia/genetics
2.
Biol Psychiatry ; 36(12): 792-800, 1994 Dec 15.
Article in English | MEDLINE | ID: mdl-7893844

ABSTRACT

Twenty eight schizophrenic patients and 20 normal volunteers underwent proton magnetic resonance spectroscopy (MRS) on the left temporal and frontal lobe regions. Male patients showed a significant reduction in frontal but not temporal n-acetylaspartate (an intraneuronally distributed metabolite) in comparison with either male controls or female patients; frontal choline was raised in male patients relative to these groups. Putative neurodevelopmental indices, including obstetric complications, family history of schizophrenia, and minor physical anomalies, proved unrelated to MRS resonances. However, multiple aspects of memory function in patients were related to temporal but not frontal creatine, a pattern that was not apparent among controls. These MRS findings complement some previous structural MRI studies and much clinical and epidemiological evidence of important gender differences in schizophrenia. The findings also suggest that memory dysfunction in patients with schizophrenia may be associated with a particular pattern of temporal lobe metabolism on MRS.


Subject(s)
Frontal Lobe/diagnostic imaging , Frontal Lobe/physiopathology , Magnetic Resonance Spectroscopy/methods , Schizophrenia/diagnostic imaging , Schizophrenia/physiopathology , Temporal Lobe/diagnostic imaging , Temporal Lobe/physiopathology , Adult , Choline/analysis , Choline/metabolism , Cognition Disorders/etiology , Creatine/metabolism , Female , Frontal Lobe/metabolism , Humans , Male , Memory Disorders/metabolism , Radiography , Schizophrenia/complications , Sex Factors , Temporal Lobe/metabolism
3.
Clin Pharmacol Ther ; 34(6): 744-8, 1983 Dec.
Article in English | MEDLINE | ID: mdl-6641089

ABSTRACT

The effects of low-dose perhexiline on the exercise training response of 22 male patients, 14 after myocardial infarction and 8 after coronary artery bypass who underwent exercise training, were examined. All subjects underwent treadmill exercise testing and resting left ventricular function evaluation by radionuclide ventriculography before and after an 8-wk course of three-times-weekly exercise training. Blood levels of perhexiline confirmed that there was a steady state sufficient for antianginal therapy. There were no side effects. There were improvements in exercise tolerance in treated and placebo groups. There were no significant intergroup differences. Resting left ventricular ejection fraction and end-systolic and diastolic dimensions were not altered. Resting blood pressures were not affected by treatment. There was no evidence of a beta-adrenoceptor-blocking effect. Perhexiline during exercise training did not impair the training response.


Subject(s)
Coronary Disease/drug therapy , Perhexiline/therapeutic use , Physical Exertion , Coronary Disease/rehabilitation , Heart Function Tests , Heart Rate/drug effects , Humans , Liver Function Tests , Male , Middle Aged , Myocardial Infarction/drug therapy , Myocardial Infarction/rehabilitation
4.
Am J Psychiatry ; 150(1): 146-8, 1993 Jan.
Article in English | MEDLINE | ID: mdl-8417558

ABSTRACT

Three patients with schizophrenia-like psychosis and two with schizoaffective-like psychosis who experienced cerebral trauma before the onset of their illness underwent clinical and magnetic resonance imaging evaluation. Each patient with a schizophrenia-like psychosis, but neither of those with a schizoaffective-like psychosis, showed abnormalities confined to or including the left temporal lobe. These observations complement recent findings in schizophrenia.


Subject(s)
Brain Injuries/complications , Brain/pathology , Magnetic Resonance Imaging , Neurocognitive Disorders/diagnosis , Psychotic Disorders/diagnosis , Schizophrenia/diagnosis , Adult , Female , Humans , Male , Middle Aged , Neurocognitive Disorders/etiology , Psychotic Disorders/pathology , Schizophrenia/pathology , Temporal Lobe/pathology
5.
J Nucl Med ; 31(9): 1557-9, 1990 Sep.
Article in English | MEDLINE | ID: mdl-2395024

ABSTRACT

Radionuclide angiography with technetium-99m-labeled macroaggregates of albumin (99mTc-MAA), was successful in a single patient with a lower limb arteriovenous (AV) malformation, not only in diagnosis and quantitation of AV shunting, but also in localizing the site of shunting. This information proved useful to the angiographer, permitting a carefully tailored examination of the area of interest. This technique may hold promise as a preliminary examination in patients with limb AV malformations prior to angiography.


Subject(s)
Arteriovenous Malformations/diagnostic imaging , Technetium Tc 99m Aggregated Albumin , Adult , Female , Humans , Leg/blood supply , Radionuclide Angiography
6.
J Nucl Med ; 26(8): 859-67, 1985 Aug.
Article in English | MEDLINE | ID: mdl-4032034

ABSTRACT

Gold-195m has found applications in first-pass studies for investigating both right and left ventricular activity as well as lung transit. Owing to its reasonably short half-life of 30 sec we have found it particularly useful for imaging leg veins up to and including the inferior vena cava. Its short half-life prevents recirculation activity from appearing, so continuous perfusion into a superficial foot vein and application of ankle tourniquets yield a steady-state image of the deep veins, with particularly good resolution. Its decay pattern along a vessel is very sensitive to blood velocity, so measurement of activity at various points on a vein in a computer static image can give velocity values that reveal abnormalities due to partial or complete thrombosis. The radiation dosimetry of 195mAu used in this way is lower than contrast and technetium-99m macroaggregated albumin [( 99mTc]MAA) venography, making it particularly useful for investigating deep vein thrombosis (DVT) in pregnancy.


Subject(s)
Blood Flow Velocity , Gold Radioisotopes , Veins/diagnostic imaging , Abdomen/blood supply , Evaluation Studies as Topic , Half-Life , Humans , Leg/blood supply , Mathematics , Models, Chemical , Radiation Dosage , Radionuclide Generators , Radionuclide Imaging , Thrombophlebitis/diagnostic imaging
7.
Eur J Cancer Prev ; 3 Suppl 1: 21-8, 1994 Jan.
Article in English | MEDLINE | ID: mdl-8130722

ABSTRACT

The Eccles Breast Screening Programme is a population-based screening programme for breast cancer, based at the Mater Misericordiae Hospital, Dublin. It began in 1989 simultaneously with similar programmes in Belgium, France, Greece, Portugal and Spain. The objectives of the Eccles Programme are: (i) to evaluate the impact of mammographic screening on morbidity and mortality from breast cancer in Irish women; and (ii) to address the feasibility and potential value of a national breast cancer screening programme. The specific group targeted for screening is women born in 1925 to 1940 inclusive, in a defined geographical area comprising north Dublin City and County, and Counties Cavan and Monaghan. The areas combined comprise 16% of the country's population; just over 29,000 women were invited for screening. An analysis of the demographic and socioeconomic features of the target population reveals that it represents the total population remarkably well. Participants were invited from a population register to attend one of two screening units. Follow-up treatment for those with abnormalities takes place predominantly at the Mater Hospital where the facilities of the Departments of Pathology, Surgery and Oncology have been made available to the programme. Almost 18,000 women had a mammogram in the first round of screening, an overall response rate of 62%. A total of 129 cancers were detected, a prevalence of breast cancer of 7.2 per 1,000. Of those, 15 (11.6%) were entirely intraduct, and an additional 7 (5.4%) had minimal invasion. This is considerably higher than the proportion of intraduct cancers seen in referral practice populations.


Subject(s)
Breast Neoplasms/prevention & control , Mammography , Mass Screening , Aged , Breast Neoplasms/diagnostic imaging , Breast Neoplasms/pathology , Carcinoma in Situ/diagnostic imaging , Carcinoma in Situ/pathology , Carcinoma in Situ/prevention & control , Continuity of Patient Care , Female , Humans , Information Systems , Ireland , Mass Screening/methods , Mass Screening/organization & administration , Middle Aged , Neoplasm Invasiveness , Neoplasm Staging , Predictive Value of Tests , Registries
8.
Med Phys ; 26(8): 1607-11, 1999 Aug.
Article in English | MEDLINE | ID: mdl-10501061

ABSTRACT

Image compression is fundamental to the efficient and cost-effective use of digital medical imaging technology and applications. Wavelet transform techniques currently provide the most promising approach to high-quality image compression which is essential for diagnostic medical applications. A novel approach to image compression based on the wavelet decomposition has been developed which utilizes the shape or morphology of wavelet transform coefficients in the wavelet domain to isolate and retain significant coefficients corresponding to image structure and features. The remaining coefficients are further compressed using a combination of run-length and Huffman coding. The technique has been implemented and applied to full 16 bit medical image data for a range of compression ratios. Objective peak signal-to-noise ratio performance of the compression technique was analyzed. Results indicate that good reconstructed image quality can be achieved at compression ratios of up to 15:1 for the image types studied. This technique represents an effective approach to the compression of diagnostic medical images and is worthy of further, more thorough, evaluation of diagnostic quality and accuracy in a clinical setting.


Subject(s)
Image Processing, Computer-Assisted/methods , Radiographic Image Enhancement/methods , Radiographic Image Interpretation, Computer-Assisted/methods , Algorithms , Biophysical Phenomena , Biophysics , Brain/diagnostic imaging , Humans , Image Processing, Computer-Assisted/statistics & numerical data , Magnetic Resonance Imaging/methods , Magnetic Resonance Imaging/statistics & numerical data , Spine/anatomy & histology , Tomography, X-Ray Computed/methods , Tomography, X-Ray Computed/statistics & numerical data
9.
Psychiatry Res ; 61(2): 95-102, 1995 Aug 08.
Article in English | MEDLINE | ID: mdl-7480392

ABSTRACT

Transverse, or spin-spin, relaxation times (T2) from magnetic resonance images of basal ganglia structures were compared between control subjects and patients with schizophrenia, who were subdivided on the basis of the presence or absence of tardive dyskinesia. As a group, schizophrenic patients showed evidence of somewhat more prolonged T2 relaxation times in the right putamen and globus pallidus than did control subjects; there were no significant correlations between hemispheric T2 values and corresponding volumes of the lateral ventricles. Overall, there was little difference in T2 values between patients with and without tardive dyskinesia. These data extend the range of evidence for basal ganglia dysfunction in schizophrenia, but they do not support earlier reports of prominent T2 changes associated with tardive dyskinesia.


Subject(s)
Basal Ganglia Diseases/diagnosis , Basal Ganglia/pathology , Dyskinesia, Drug-Induced/diagnosis , Magnetic Resonance Imaging , Schizophrenia/diagnosis , Schizophrenic Psychology , Adult , Antipsychotic Agents/adverse effects , Antipsychotic Agents/therapeutic use , Basal Ganglia/drug effects , Basal Ganglia Diseases/chemically induced , Cerebral Ventricles/drug effects , Cerebral Ventricles/pathology , Dominance, Cerebral/drug effects , Dominance, Cerebral/physiology , Female , Globus Pallidus/drug effects , Globus Pallidus/pathology , Humans , Male , Middle Aged , Neurologic Examination/drug effects , Putamen/drug effects , Putamen/pathology , Schizophrenia/drug therapy
10.
Br J Radiol ; 73(873): 994-8, 2000 Sep.
Article in English | MEDLINE | ID: mdl-11064654

ABSTRACT

Cell phone use is growing worldwide. These phones transmit to adjacent base stations using radiofrequency signals in the microwave range (approximately 900-approximately 1800 MHz). Portable electronic dose monitoring equipment is used in hospitals and other institutions to monitor and control levels of exposure to ionizing radiation, and to reassure staff. The objective of this paper is to investigate the effect of mobile phones on a sample of dose monitoring devices. Two mobile phones (Siemens C25 and Motorola CD930) were used in the study. Field strengths were measured to be in the range 0 V m-1 to over 100 V m-1, depending on the distance from the phone, and were strongest at the beginning of a call. Personal electronic dosemeters (n = 7), portable dose monitors (n = 4) and contamination monitors (n = 2) were assessed. All the units were in service. Three of the personal dosemeters showed abnormal responses when exposed to mobile phone transmission. One dosemeter (Siemens EPD-2) registered doses equivalent to a dose rate of 99 mSv h-1. In addition, two of the portable dosemeters and one of the contamination monitors also gave an abnormal response. Interference was observed across a number of detector types from a number of manufacturers. Modern cell phones can interfere with ionizing radiation dose monitoring equipment. This should be taken into account when distributing these devices and when assessing results generated by them. Electromagnetic compatibility testing should form part of the commissioning and specification protocol for new dose monitoring equipment.


Subject(s)
Radiometry/instrumentation , Telephone , Electromagnetic Fields , Equipment Failure , Radiation, Ionizing
11.
Br J Radiol ; 65(780): 1097-101, 1992 Dec.
Article in English | MEDLINE | ID: mdl-1286417

ABSTRACT

In contrast to the majority of mammographic breast screening programmes, film processing at this centre occurs on site in both hospital and mobile trailer units. Initial (1989) quality control (QC) sensitometric tests revealed a large variation in film processor performance in the mobile unit. The clinical significance of these variations was assessed and acceptance limits for processor performance determined. Abnormal mammograms were used as reference material and copied using high definition 35 mm film over a range of exposure settings. The copies were than matched with QC film density variation from the mobile unit. All films were subsequently ranked for spatial and contrast resolution. Optimal values for processing time of 2 min (equivalent to film transit time 3 min and developer time 46 s) and temperature of 36 degrees C were obtained. The widespread anomaly of reporting film transit time as processing time is highlighted. Use of mammogram copies as a means of measuring the influence of film processor variation is advocated. Careful monitoring of the mobile unit film processor performance has produced stable quality comparable with the hospital based unit. The advantages of on site film processing are outlined. The addition of a sensitometric step wedge to all mammography film stock as a means of assessing image quality is recommended.


Subject(s)
Mammography/standards , Mass Screening/standards , Mobile Health Units/standards , Radiology Department, Hospital/standards , X-Ray Film/standards , Breast Neoplasms/prevention & control , Female , Humans , Ireland , Quality Control , Sensitivity and Specificity
12.
Br J Radiol ; 56(662): 109-12, 1983 Feb.
Article in English | MEDLINE | ID: mdl-6218852

ABSTRACT

The uptake and elimination of 99Tcm labelled MAA were followed by gamma camera and computer over a period of 36 hours in patients undergoing lung scanning and venography. Lungs, stomach, kidneys, GI tract, bladder and thyroid showed significant concentrations of activity at various times after the injection of radiopharmaceutical, with carefully controlled labelling efficiency. There was no indication of accumulation in the liver or spleen. Activity versus time curves were constructed. The lung curve had approximately bi-exponential form with components of effective half-lives 0.88 and 4.56 h. Areas beneath the curves gave cumulated activities for each organ and, using S values (absorbed dose per unit cumulated activity) from MIRD tables, absorbed doses from self-irradiation were calculated for each organ.


Subject(s)
Serum Albumin/metabolism , Technetium/metabolism , Gastric Mucosa/metabolism , Humans , Intestinal Mucosa/metabolism , Kidney/metabolism , Kinetics , Lung/diagnostic imaging , Lung/metabolism , Phlebography , Radiation Dosage , Radionuclide Imaging , Technetium Tc 99m Aggregated Albumin , Thyroid Gland/metabolism , Urinary Bladder/metabolism
13.
Br J Radiol ; 64(759): 210-6, 1991 Mar.
Article in English | MEDLINE | ID: mdl-2021793

ABSTRACT

In vivo phosphorus-31 magnetic resonance spectroscopy, at 1.5 T, in addition to magnetic resonance imaging and mammography, was performed on the breast tissue of 59 subjects, using a 40 mm or 80 mm surface coil for spectral localization. The patients were divided into three groups: Group 1, 46 control subjects; Group 2, nine patients with breast carcinoma; Group 3, four patients with benign breast disease. The relationship of age, menopausal status, breast size and pattern, use of contraceptive pill and history of breast disease to spectral characteristics of breast tissue was examined for the control group. In multivariate analysis, only menopausal status and age were found to be significantly related to tissue biochemistry. Pre-menopausal women had reduced phosphocreatine (PCr) (%) (p = 0.02), and increased phosphomonoesters (PMEs) and beta-nucleotide triphosphate (beta-NTP) (%) (p = 0.05), while the fat-to-water ratio was higher in older women (p = 0.02). No significant differences were identified between the control subjects and the patients with benign breast disease. When spectra from patients with breast carcinoma were compared with an age-matched volunteer group, alpha- and gamma-NTP (%) were found to be higher in the cancer tissue (p less than 0.01 and p = 0.01, respectively), while PCr (%) was reduced (p less than 0.01). The ratio beta-NTP:PCr was higher in the carcinoma group of patients (p less than 0.05). In vivo phosphorus-31 magnetic resonance spectroscopy is a non-invasive examination which may prove useful in the early differentiation of malignant breast disease from normal and benign conditions.


Subject(s)
Breast Diseases/diagnosis , Breast/pathology , Magnetic Resonance Spectroscopy , Aged , Breast Diseases/genetics , Breast Diseases/metabolism , Breast Feeding , Breast Neoplasms/diagnosis , Contraceptives, Oral , Female , Humans , Magnetic Resonance Imaging , Menopause , Middle Aged , Multivariate Analysis , Phosphorus/metabolism
14.
J Bone Joint Surg Br ; 64(4): 450-3, 1982.
Article in English | MEDLINE | ID: mdl-7096419

ABSTRACT

Seventy-seven children admitted with a provisional diagnosis of acute osteomyelitis over a three year period have been reviewed. Acute haematogenous osteomyelitis was confirmed in 45 of these patients whose ages varied from three days to 14 years with a mean of 6.2 years. All patients were treated with intravenous fusidic acid and cloxacillin with splintage for three weeks followed by oral antibiotics for a further period of six weeks. Only seven patients required operation. One patient had recurrence of infection; all other patients were cured with no evidence of chronic osteomyelitis. It is suggested that surgical drainage of acute haematogenous osteomyelitis is seldom needed and that high intravenous doses of antibiotics in combination with splintage are adequate treatment in most cases.


Subject(s)
Cloxacillin/administration & dosage , Fusidic Acid/administration & dosage , Osteomyelitis/therapy , Splints , Acute Disease , Adolescent , Child , Child, Preschool , Drug Therapy, Combination , Humans , Infant , Infant, Newborn , Osteomyelitis/diagnosis , Prognosis
15.
J R Soc Med ; 85(4): 227-31, 1992 Apr.
Article in English | MEDLINE | ID: mdl-1433067

ABSTRACT

The nature of abnormalities of cerebral structure evident in schizophrenia on magnetic resonance imaging is considered in relation to the neurodevelopmental hypothesis of the disorder. While schizophrenic patients showed increased ventricular volume, the extent of increase with age was comparable with that evident in controls and was unrelated to duration of illness. Conversely, cortical atrophy was evident only in patients, and this increased markedly with age and duration of illness. Such findings could be suggestive of two distinct pathophysiological processes in schizophrenia, but a schema for their reconciliation with the neurodevelopmental hypothesis is elaborated.


Subject(s)
Brain/pathology , Magnetic Resonance Imaging , Schizophrenia/pathology , Adult , Age Factors , Aged , Brain/embryology , Cerebral Cortex/pathology , Cerebral Ventricles/pathology , Female , Humans , Male , Middle Aged
16.
Ir J Med Sci ; 162(3): 82-5, 1993 Mar.
Article in English | MEDLINE | ID: mdl-8473127

ABSTRACT

In order to define the role of Single Photon Emission Computed Tomography (SPECT) in the diagnosis of pulmonary embolus; SPECT and Planar ventilation and perfusion lung studies were performed consecutively on eleven patients referred with suspected embolus. Three patients were shown to have 'high probability' ventilation perfusion mismatches. SPECT imaging allowed segmental localisation of the perfusion defect and revealed additional defects not seen on planar scans. SPECT lung study was performed with minimal technical difficulty and was well tolerated by all patients studied. SPECT is likely to become the method of choice for investigating patients referred with suspected pulmonary embolus.


Subject(s)
Pulmonary Embolism/diagnostic imaging , Tomography, Emission-Computed, Single-Photon , Adult , Aged , Humans , Middle Aged , Pulmonary Embolism/physiopathology , Sensitivity and Specificity , Ventilation-Perfusion Ratio
17.
Ir J Med Sci ; 148(1): 140, 1979 Dec.
Article in English | MEDLINE | ID: mdl-27517405

ABSTRACT

The results of a prospective randomised study in a series of 106 patients undergoing Charnley total hip arthroplasty are discussed. All were consecutive and no one was excluded on the grounds of previous medical history. Fifty-five received prophylactic Dextran while 51 acted as controls. A total of 867 separate studies were performed on these patients. Radionuclide venography was employed to detect deep vein thrombosis and perfusion lung scanning for pulmonary emboli. Eighteen per cent of the control patients and 27% of the Dextran patients developed deep vein thrombosis. Pulmonary emboli occurred in 16% of the patients in each group. The overall incidence of thromboembolic disease was 27% in the control and 36% in the Dextran group. A prophylactic effect of Dextran was not demonstrated.

SELECTION OF CITATIONS
SEARCH DETAIL