AIMS: To investigate the morphology of the optic disc and retinal vessels in children with surgically treated hydrocephalus. METHODS: A prospective, population-based study was performed in 69 children (median age 9.6 years) with early surgically treated hydrocephalus. All children were examined by ophthalmoscopy. Additionally, optic disc and retinal vessel morphology was evaluated in 55 children by digital image analysis of ocular fundus photographs. RESULTS: Optic atrophy was found in 10 of 69 children (14%). In comparison with a reference group, the median optic-disc area was significantly smaller (p = 0.013) in the children with hydrocephalus. There was no corresponding difference in cup area, so the rim area was significantly smaller in the hydrocephalic children (p = 0.002). Children with hydrocephalus had an abnormal retinal vascular pattern, with significantly straighter retinal arteries and fewer central vessel branching points compared with controls (p
A computer method enabling metric measuring in radiographs has been presented. The measurements are time saving and precise and accurate measurements can be made. The statistical analysis can be performed based on a ratio scale, allowing more reliable and conclusive statistics. The most useful field for the presented method is offered in epidemiology where great materials are being handled. Since small changes can be studied, the method can be useful in studying marginal bone level changes in large populations. Or marginal bone levels around implants. In age estimation the digitizer method has no direct valuable application during adolescence, when the lower third molar is used. Here the present series of studies showed the traditional age estimation method and the digitizer method to be fairly unprecise with rather large systematic error. The skeletal age estimation method according to Greulich and Pyle was found to be more accurate and useful during the ages 14 up to 18 years. In younger children, where more parameters or teeth are available, there may be advantages to use a digital dental method instead of a traditional dental one.
Acute administration of a single dose of valsartan improves left ventricular functions: a pilot study to assess the role of tissue velocity echocardiography in patients with systemic arterial hypertension in the TVE-valsartan study I.
BACKGROUND: The advent of colour-coded tissue velocity echocardiography (TVE) has now made it possible to quantify left ventricular (LV) functions in patients with systemic arterial hypertension (HTN). Hypothesis In this project, we have studied the cardiac effects of a single dose of orally administered valsartan in patients with known HTN. METHODS: Fifty-five patients with HTN with a mean age of 56 +/- 10 years were given an early morning dose of 80 mg valsartan withholding regular antihypertensive medications on the day of investigation. TVE images, acquired on VIVID systems were digitized for postprocessing of longitudinal and radial peak systolic velocities, strain rate, and systolic and diastolic time intervals before (pre) and 5 h after (post) administration of the drug. RESULTS: Blood pressure (mmHg) pre and post, respectively, were 147 +/- 15 versus 137 +/- 14 systolic and 90 +/- 7 versus 86 +/- 7 diastolic (all P
Fully automated assessment of mammographic density (MD), a biomarker of breast cancer risk, is being increasingly performed in screening settings. However, data on body mass index (BMI), a confounder of the MD-risk association, are not routinely collected at screening. We investigated whether the amount of fat in the breast, as captured by the amount of mammographic non-dense tissue seen on the mammographic image, can be used as a proxy for BMI when data on the latter are unavailable.
Data from a UK case control study (numbers of cases/controls: 414/685) and a Norwegian cohort study (numbers of cases/non-cases: 657/61059), both with volumetric MD measurements (dense volume (DV), non-dense volume (NDV) and percent density (%MD)) from screening-age women, were analysed. BMI (self-reported) and NDV were taken as measures of adiposity. Correlations between BMI and NDV, %MD and DV were examined after log-transformation and adjustment for age, menopausal status and parity. Logistic regression models were fitted to the UK study, and Cox regression models to the Norwegian study, to assess associations between MD and breast cancer risk, expressed as odds/hazard ratios per adjusted standard deviation (OPERA). Adjustments were first made for standard risk factors except BMI (minimally adjusted models) and then also for BMI or NDV. OPERA pooled relative risks (RRs) were estimated by fixed-effect models, and between-study heterogeneity was assessed by the I2 statistics.
BMI was positively correlated with NDV (adjusted r = 0.74 in the UK study and r = 0.72 in the Norwegian study) and with DV (r = 0.33 and r = 0.25, respectively). Both %MD and DV were positively associated with breast cancer risk in minimally adjusted models (pooled OPERA RR (95% confidence interval): 1.34 (1.25, 1.43) and 1.46 (1.36, 1.56), respectively; I2 = 0%, P >0.48 for both). Further adjustment for BMI or NDV strengthened the %MD-risk association (1.51 (1.41, 1.61); I2 = 0%, P = 0.33 and 1.51 (1.41, 1.61); I2 = 0%, P = 0.32, respectively). Adjusting for BMI or NDV marginally affected the magnitude of the DV-risk association (1.44 (1.34, 1.54); I2 = 0%, P = 0.87 and 1.49 (1.40, 1.60); I2 = 0%, P = 0.36, respectively).
When volumetric MD-breast cancer risk associations are investigated, NDV can be used as a measure of adiposity when BMI data are unavailable.
Avian vocal control regions of adult male songbirds contain opioid peptides and receptors, suggesting that opioids play a role in avian vocal behavior control. In a previous study, we found no difference in opioid receptor densities in singing versus nonsinging adult male dark-eyed juncos (Junco hyemalis), leading us to hypothesize that opioids are not involved in controlling song production. To assess whether opioids may be involved in other aspects of vocal behavior, we used quantitative in vitro autoradiography to compare mu and delta opioid receptor densities in vocal control regions of singing adult males with those of adult females and adolescent (about 3 months old) males and females. We found mu and delta receptors in all vocal control regions measured. Adolescents had significantly higher opioid receptor densities than did adults in area X (delta), robust n. of the archistriatum (delta and mu), and n. intercollicularis (mu), suggesting a developmental role for opioids in the vocal control system. Based on opioid roles in other animal models, we propose that opioids may be involved in song learning, auditory processing, and/or vocal control system development.
Quantitative analyses of brain structures from Magnetic Resonance (MR) image data are often performed using automatic segmentation algorithms. Many of these algorithms rely on templates and atlases in a common coordinate space. Most freely available brain atlases are generated from relatively young individuals and not always derived from well-defined cohort studies. In this paper, we introduce a publicly available multi-spectral template with corresponding tissue probability atlases and regional atlases, optimised to use in studies of ageing cohorts (mean age 75 ± 5 years). Furthermore, we provide validation data from a regional segmentation pipeline to assure the integrity of the dataset.
Cites: Neuroimage. 2010 Feb 1;49(3):2352-65 PMID 19857578
To establish the agreement between image grading of conventional (45°) and ultra wide-angle (200°) digital images in the macula.
In 2008, the 12-year follow-up was conducted on 573 participants of the Reykjavik Eye Study. This study included the use of the Optos P200C AF ultra wide-angle laser scanning ophthalmoscope alongside Zeiss FF 450 conventional digital fundus camera on 121 eyes with or without age-related macular degeneration using the International Classification System. Of these eyes, detailed grading was carried out on five cases each with hard drusen, geographic atrophy and chorioretinal neovascularisation, and six cases of soft drusen. Exact agreement and ?-statistics were calculated.
Comparison of the conventional and ultra wide-angle images in the macula showed an overall 96.43% agreement (?=0.93) with no disagreement at end-stage disease; although in one eye chorioretinal neovascularisation was graded as drusenoid pigment epithelial detachment. Of patients with drusen only, the exact agreement was 96.1%. The detailed grading showed no clinically significant disagreement between the conventional 45° and 200° images.
On the basis of our results, there is a good agreement between grading conventional and ultra wide-angle images in the macula.
The occurrence, structure and extent of microvascular density were examined in normal endometria, hyperplasia of different types and adenocarcinomas of different degrees of differentiation to determine their biologic and clinical significance in tumor development and progression. Computer-assisted quantitative image analysis was carried out on 12,500 vessels in regard to vessel number, vessel volume, size, shape and extent of vessel antibody staining, with sensitivity and reproducibility exceeding 99%. The results showed the extent, pattern and characteristics of microvascular density to be intimately associated with extent of tumor development and degree of differentiation of the tumor. Vessel number increased with superficial location in normal endometrium, with increased degree of hyperplasia and atypia and with increased degree of dedifferentiation of adenocarcinoma. Increased vessel shape alterations were characteristic of atypical complex hyperplasia when compared to other types of hyperplasia. Vessel number, size and shape were similar in proliferative endometrium and simplex type hyperplasia, and microvascular density in atypical complex hyperplasia was similar to that in well-differentiated adenocarcinoma. The results indicated that vessel shape alterations occur during progression of hyperplasia and vessel size increase occurs in complex-type hyperplasia and in moderately differentiated adenocarcinomas. We conclude that microvascular density is associated with endometrial location and with specific patterns of alteration in different stages of endometrial disease. The results suggest potential clinical applications of vessel analysis for determination of clinical behavior of endometrial preneoplastic and neoplastic alterations.
Early diagnosis of Alzheimer's disease (AD) is critical for adequate treatment and care. Recently it has been shown that functional magnetic resonance imaging (fMRI) can be important in preclinical detection of AD. The purpose of this study was to examine possible differences in memory-related brain activation between persons with high versus low risk for AD. This was achieved by combining a validated neurocognitive screening battery (the 7-minutes test) with memory assessment and fMRI.
One hundred two healthy community-living persons with subjective memory complaints were recruited through advertisement and tested with the 7-minutes test. Based on their test performance they were classified as having either high (n = 8) or low risk (n = 94) for AD. Six high-risk individuals and six age-, sex-, and education-matched low-risk individuals were investigated with fMRI while engaged in episodic memory tasks.
The high-risk individuals performed worse than low-risk individuals on tests of episodic memory. Patterns of brain activity during episodic encoding and retrieval showed significant group differences (p