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D B Hier

Publications and source records attributed to D B Hier.

At least 19 recordsLinked to original sources
PubMed2000

Ischemic strokes are more severe in Poland than in the United States.

Case fatality rates for stroke were ascertained prospectively in two regional catchment hospitals in Poland and 36 teaching hospitals in the US University Hospital Consortium. Case fatality rates in Poland (23.9%) were higher than in the United States (7.5%). Angina, atrial fibrillation, and congestive heart failure were more frequent in Polish stroke patients (40%, 26%, and 25%, respectively) than in US patients (17%, 12%, and 10%). Stroke severity as indicated by higher frequencies of hemiplegia, disordered consciousness, dysphagia, and aphasia was greater in Poland (19%, 39%, 28%, and 42%, respectively) than the United States (11%, 13%, 14%, and 26%).

Adolescent↗
PubMed1999

Applying wavelet-transform on Internet-based radiologic brain images.

Wavelet-transform compression creates high-quality images of small file size by tuning its compression ratio between 10:1 and 80:1. We applied the wavelet-based compression technique to radiologic brain images on the Internet for image display purposes. Wavelet transform compression reduces file size up to 50%. Wavelet transform compression offers the advantage of retaining complete color information in digital images and faster Internet transmission than traditional Joint Photography Experts Group (JPEG) files of equivalent file size. The application of wavelet-based compression technique decreases storage requirements for images on Internet servers.

Brain↗
PubMed1999

Anticardiolipin antibodies are an independent risk factor for ischemic stroke.

Our aim was to determine if anticardiolipin antibodies are an independent risk factor for ischemic stroke and to determine their influence on stroke type and clinical outcome. We prospectively studied 194 consecutive patients with ischemic stroke admitted within 48 h of stroke. A control group consisted of 100, age and sex matched, healthy individuals. Neurological and functional status was assessed on admission, at 30 days, and at 1 year. IgG anticardiolipin antibodies were significantly more frequent in stroke patients (25.3%) than controls (6%, p < 0.05). A multivariate analysis suggested that anticardiolipin antibodies are an independent risk factor for ischemic stroke in addition to hypertension and atrial fibrillation (RR = 2.94, p < 0.05). Elevated IgG anticardiolipin antibodies were associated with cognitive impairment as measured by the Mini Mental State Examination at 30 days and at 1 year. IgG anticardiolipin antibodies did not correlate with stroke recurrence, or mortality at 30 days or 1 year.

Adult↗
PubMed1999

The display of photographic-quality images on the Web: a comparison of two technologies.

Downloading medical images on the Web creates certain compromises. The tradeoff is between higher resolution and faster download times. As resolution increases, download times increase. High-resolution (photographic quality) electronic images can potentially play a key role in medical education and patient care. On the Internet, images are typically formatted as Graphics Interchange Format (GIF) or the Joint Photographic Experts Group (JPEG) files. However, these formats are associated with considerable data loss in both color depth and image resolution. Furthermore, these images are available in a single resolution and have no capability of allowing the user to adjust resolution as needed. Images in the photo compact disc (PCD) format have higher resolutions than GIF or JPEG, but suffer the disadvantage of large file sizes leading to long download times on the Web. Furthermore, native web browsers are not currently able to read PCD files. The FlashPix format (FPX) offers distinct advantages over the PCD, GIF, and JPEG formats for display of high-resolution images on the Web. A Java applet can be easily downloaded for viewing FPX images. FPX images are higher resolution than JPEG and GIF images. FPX images offer rich resolutions comparable to PCD images with shorter download times.

Internet↗
PubMed1998

Visual form of Alzheimer's disease and its response to anticholinesterase therapy.

In a 60-year-old woman with the visual variant of Alzheimer's disease, single photon emission computed tomography abnormalities were most marked in the parieto-occipital regions of the brain. After treatment with donepezil, improvement is noted on neuropsychological testing and on brain SPECT, including increased perfusion (metabolism) in the occipital lobes.

Alzheimer Disease↗
PubMed1997

Normalization of transcranial Doppler middle cerebral artery velocities after aneurysm clipping.

BACKGROUND: Factors that promote normalization of middle cerebral artery (MCA) velocities after cerebral aneurysm surgery may be important to identify in order to optimize management. Survival analysis of serial transcranial Doppler (TCD) MCA velocities in the setting of aneurysm surgery offers an additional means of analyzing outcome. METHODS: We retrospectively studied serial MCA velocities obtained via TCD in 113 patients who underwent cerebral aneurysm clipping to analyze which factors promoted normalization. The presence of bleeding, aneurysm location, age, gender, ethnicity, initial blood pressure, hemoglobin, and clinical condition were examined. RESULTS: Patients who did not bleed but were clipped still tended to have transient periods of abnormally elevated velocities. Of those patients who bled and were clipped, older patients normalized faster. Women showed a trend toward slower normalization only in the subarachnoid hemorrhage (SAH) absent group. Other parameters listed above did not effect normalization time. CONCLUSIONS: Our data suggest aneurysm surgery in and of itself may promote transient rises in MCA velocities. Age appears to be a significant factor in predicting normalization of MCA velocities after SAH.

Adult↗
PubMed1997

Stroke recurrence among 30 days survivors of ischemic stroke in a prospective community-based study.

A cohort of 209 patients (105 men and 104 women), who survived 30 days after 'first ever-in-lifetime ischemic stroke' were followed for one year. Predictors of survival were examined by log-rank test and Cox proportional hazards method. Twenty-four patients had a stroke recurrence (11.4%). Thirteen of the patients with recurrent stroke (54%) died because of the sequelae of the second stroke. Stroke recurred in 16% of patients with stroke due to atherosclerosis, in 12.5% of patients with cardioembolic stroke, and in 4.4% of patients with lacunar stroke. The life table cumulative risk of death at 6 and 12 months for patients with recurrent stroke was statistically higher (22% and 57%) than patients without recurrent stroke (13% and 29% respectively). History of untreated hypertension prior to the initial stroke (RR = 1.7, 95% Cl 1.2-4.1, p < 0.05) was an independent predictor of recurrence. In 134 patients (64.9%) aspirin was initiated during the first month after stroke. Only 81 patients (39.8%) continued aspirin treatment for the whole year. Life table cumulative risk of mortality among the patients treated with aspirin was 8% at 6 months and 12% at 1 year compared to 19% at 6 months and 45% at 12 months for those untreated with aspirin. We conclude that the high risk of recurrent stroke in Poland could be redaced by increased use of anti-platelets therapy and anti-hypertensive therapy after ischemic stroke.

Aged↗
PubMed1997

Stroke mortality rates in Poland did not decline between 1984 and 1992.

BACKGROUND AND PURPOSE: Stroke mortality has decreased in most industrialized countries in recent decades. In Poland, as in other eastern European countries, mortality rates for stroke remain high. METHODS: The Warsaw Stroke Registry (WSR) registered patients in the Mokotów district of Warsaw from 1991 through 1992. The Warsaw Pol-MONICA study registered stroke patients in the North and South Praga regions of Warsaw from 1984 through 1992. Stroke incidence rates, case-fatality rates, and stroke mortality rates were computed based on both studies and compared with published mortality rates based on death certificates. Eight-year trends of stroke incidence, case-fatality rate, and mortality were derived from the Warsaw Pol-MONICA study. RESULTS: The WSR and Warsaw Pol-MONICA studies showed similar incidence rates, mortality rates, and 28-day case-fatality rates for stroke. Mortality rates from the WSR and the Warsaw Pol-MONICA study were similar to rates from death certificate data. Mortality rates in the group aged 35 to 64 years were higher in men (47.5 to 50/100000 per year) than in women (30/100000 per year). CONCLUSIONS: Two different population-based studies suggest that stroke mortality is high in Poland because of high 28-day case-fatality rates. Stroke mortality failed to decline in Poland in the period 1984 through 1992 because neither case fatality nor stroke incidence declined in this period.

Adult↗
PubMed1996

MCA flow asymmetry is a marker for cerebrovascular disease.

Utilizing the UIC Vascular Laboratory Registry, we retrospectively analysed the significance of side to side middle cerebral artery (MCA) flow velocity differences. Side to side differences > 15 percent measured by transcranial Doppler were considered asymmetric. Asymmetric subjects had 5 times greater chance of having significant cervical carotid narrowing on either side on Duplex Doppler and a 3.7 times greater chance of having a stroke on brain CT or MRI. MCA flow velocity asymmetry is a marker for underlying carotid disease and stroke.

Blood Flow Velocity↗
PubMed1995

'Morphing' class filter: an interactive tool for continuous adjustment of tissue type related contrast.

The proposed class filter increases tissue type related contrast in MR images of brain. During the first phase of the filtering process tissue type classes are defined. This is done by operator intervention, or by a semiautomatic process based either on a supervised or unsupervised classifier, respectively. During the second phase a pixel intensity transform makes pixels of the same tissue class appear 'more similar' while the pixel intensities of different classes will become 'more different', in effect increasing the tissue type related contrast. For example, normal mixture cluster analysis is performed on an MR image set obtained by varying pulse sequence (PS) parameters and provides unsupervised definition of classes while taking advantage of much greater information content of the whole image set in comparison to that of a single image. The algorithm permits continuous transition ('morphing') between the original image and the tissue classification image that has been calculated from the input image set by simple sliding cursor-bar on the computer screen under the physician's control. Consequently, the resulting images do not require retraining of the physician who is already familiar with the appearance of standard MR images and they make mental integration of information from a large input image set possible and easier.

Brain↗
PubMed1994

Gender and aphasia in the Stroke Data Bank.

Aphasia was present in 19.4% of the men and 22.5% of the women in the Stroke Data Bank. There were no gender differences in aphasia incidence among the intracerebral hemorrhages. Aphasia was more frequent among women with infarcts (37.0%) than men (28.3%). When stroke mechanism was controlled for, there was an excess of aphasia among the women with stroke due to cardiac embolism. When stroke site was controlled for, there were no gender differences in aphasia frequency. Wernicke's, global, and anomic aphasias were more common in women than men; Broca's aphasia was somewhat more common in men. Although there were no gender differences in infarct size overall, men with aphasia had larger infarcts than women with aphasia. Although gender differences were small, the infarct lesions producing aphasia in men were more posteriorly placed and the infarct lesions in women were more anteriorly placed, suggesting possible gender differences in the positioning of the language zone in the brain.

Aged↗
PubMed1994

Parametric modeling of stroke recurrence.

Stroke recurrence has been investigated primarily with respect to prognostic factors predictive of recurrence. Several parametric functions are considered in modeling the distribution of ischemic stroke recurrences recorded within the Stroke Data Bank. A linear hazard function is shown to be the best-fitting function among those considered. This method of parametric modeling may lead to a more informed approach to treatment of ischemic stroke and secondary prevention and may enhance future investigations of prognostic factors as well.

Cerebral Infarction↗
PubMed1994

A prospective community-based study of stroke in Warsaw, Poland.

BACKGROUND AND PURPOSE: Poland is a country with high morbidity and mortality rates from cardiovascular diseases. No recent studies have evaluated the contribution of cerebrovascular diseases to this morbidity and mortality. Our aim was to accurately determine stroke incidence rates in Warsaw, Poland. METHODS: A 2-year prospective and population-based stroke registry was maintained for health care units 2 and 3 in Warsaw, Poland (population, 182,285). Case subjects were ascertained by surveying hospital admissions, outpatient visits, and death certificates. RESULTS: During the 2 years of the study (1991 to 1992), 633 cases of first-event strokes were registered, 462 of which were first ever in a lifetime. Computed tomography or necropsy was performed in 72% of first-ever stroke cases. The crude annual incidence rate for first-ever stroke was 127/100,000 (95% confidence intervals, 111 to 145); the rate standardized to the European population was 111 (95% confidence intervals, 96 to 128). Our incidence rates for first-event strokes were found to be in the middle of the range among other first-event studies. When comparing our first-ever stroke incidence rates with those of comparable studies performed throughout Europe, they were found to be similar for groups aged younger than 65 years but lower in the older age groups. The distribution of ischemic and hemorrhagic stroke subtypes was similar to that of other countries. CONCLUSIONS: This first population-based prospective stroke registry in Poland showed that incidence rates were not high compared with other studies throughout Europe and the world. These stroke incidence rates are not a large contributing factor to high cardiovascular morbidity rates in Poland.

Adult↗