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At least 739 records · Page 41Linked to original sources
PubMed1984

Evaluating visual loss with multi-flash campimetry.

Multi-flash campimetry is a computer-implemented psychophysical technique that allows temporal resolution to be assessed in 120 points per eye in a half hour. It has previously been reported that the results can serve to distinguish between multiple sclerosis patients and control subjects. We have now used this technique to measure temporal resolution in patients with amblyopia, cataracts, optic neuritis or macular degeneration. Our results indicate that multi-flash campimetry is at least as sensitive to visual loss in patients with amblyopia or cataracts as visual acuity testing with the Snellen chart and kinetic visual field testing with the Goldmann perimeter. Further, multi-flash campimetry may be more sensitive than the other two techniques to subtle residual loss in patients who have had optic neuritis and to early loss in patients with macular degeneration.

Adult↗
PubMed1981

Menopausal hot flashes: their cycles and relation to air temperature.

The occurrence of hot flashes was investigated exhaustively in 1 woman. She recorded the clock time of each hot flash in a notebook for 100 days. Fluctuations were circadian and day to day with sawtoothed periodicity. The circadian peak was always between 18 and 21 hours. The circadian nadir and the mean daily rate varied directly with outdoor temperature. The occurrence of hot flashes was not related to internal body temperature, and hence not to environmental heating or cooling of the body. Therefore impulses from temperature receptors altered the rate of formation and release of a hypothetic central nervous system neurohumor that stimulated the hypothalamic heat loss center. This mechanism did not exhibit acclimatization to heat. Comparably thorough studies on more women are needed.

Body Temperature↗
PubMed1993

Detection of viable tumor cells in hepatocellular carcinoma following transcatheter arterial chemoembolization with iodized oil. Pathologic correlation with dynamic turbo-FLASH MR imaging with Gd-DTPA.

To evaluate the effect of transcatheter arterial chemoembolization (TACE) with iodized oil for hepatocellular carcinoma (HCC), dynamic turbo-fast low angle shot (turbo-FLASH) (TR/TE/flip angle/TI, 8.5/4.6/10/200) MR imaging with gadopentetate dimeglumine was performed in 10 patients with HCC after TACE with iodized oil and before partial hepatectomy. Immediately after 0.05 mmol/kg b.w. of gadopentetate dimeglumine was administered intravenously, 10 images were obtained in the first 20 s (early phase). Then, one image every 30 s from 1 to 3 min (late phase), and images at 5 min and 7 min (delayed phase) were obtained serially. In the early phase, HCC showed no enhancement in 5 patients, partial hyperintense enhancement in 4, and total hyperintense enhancement in one. Viable regions of the tumor, evaluated at histopathology, showed hyperintense enhancement relative to the surrounding liver parenchyma in the early phase, while necrotic regions showed no enhancement. Both viable and necrotic regions showed lower signal intensities than the surrounding liver parenchyma in both late and delayed phases. By using dynamic turbo-FLASH MR imaging, we were able to accurately evaluate the effect of TACE with iodized oil for HCC in 8 of the 10 patients. In 2 patients, in whom small viable cells were seen in the HCC, viable regions could not be detected with our technique. It is concluded that turbo-FLASH dynamic MR imaging was useful for evaluating the effect of TACE for HCC.

Aged↗
PubMed1996

Falsely nonrecordable flash visual evoked cortical potentials in a diabetic eye with severe vitreous hemorrhage.

The examination of visual evoked cortical potentials (VECPs) prior to vitrectomy has been proposed for selection of patients with good chances for a favorable outcome following surgery. A missing single flash VECP has been considered a contraindication for further surgical treatment. A 64-year-old woman with proliferative diabetic retinopathy suffered from an intensive vitreous hemorrhage in one eye. Preoperatively, the flash VECP was nonrecordable. Intraoperatively, a dense vitreous hemorrhage and retrohyaloidal blood was found. The retina was attached. Postoperatively, the flash VECP was similar in both eyes with normal latencies. The visual acuity improved from light perception to 0.05. Severe vitreous hemorrhage may interfere with preoperative VECP recordings. A nonrecordable VECP has to be judged cautiously so as to prevent false-negative responses in eyes that could regain vision following vitrectomy and removal of the hemorrhage.

Diabetic Retinopathy↗
PubMed1997

[Aging of the blue mechanism studied by measuring the increment threshold on flashed background].

We studied aging of the blue cone mechanism by measuring increment thresholds for detection of a small blue flash of light (439 nm, 1 degree, 50 ms duration) on a second flashed light of identical color, (139 nm, 2 degrees, 500 ms duration) in 30 subjects. Simultaneously, a large yellow adapting field was presented. Subjects, consisting of 17 normal cases, 13 cases with refraction errors under 3 diopters, 11 myopes, and 2 hyperopes, with 1.0 or better corrected visual acuity, were divided into 4 groups by age. The control group consisted of 11 cases under 30 years, group I, 7 cases in their forties, group II, 6 cases in their fifties, and group III, 6 cases over 60 years. Best fitting exponential curves were calculated for this phase of the blue mechanism and averaged threshold curves for each group were evaluated. The averaged threshold curve in group I showed an upper shift, that is, an increase in the threshold alone. Curves in groups II and III demonstrated an upper right shift, with increased thresholds in both the blue flash and the yellow background. Together with decreased function of the blue cone mechanism, the shift of curves in the elderly groups is probably caused largely by yellowing of the crystalline lens.

Adult↗
PubMed1996

[Use of pattern and flash visual evoked potentials in differential diagnosis of optic neuropathy].

PURPOSE: To assess the value of pattern and flash stimulus of visual evoked potentials (VEP) in patients with optic neuropathy. MATERIAL AND METHODS: The study involved 11 patients with compressive optic neuropathy, 19 with acute optic neuritis and 22 with demyelinating optic neuropathy. The control group included 20 persons without history of ocular and neuroophthalmologic diseases. In all patients VEP were performed using pattern and flash stimulus. Multidimensional analysis of variance (MANOVA) was used which allowed to evaluate the differentiation efficacy in respective parameters as well as the whole distinguishable classes. RESULTS: The efficacy of differential diagnosis of examined optic neuropathy with pattern or flash VEP was not sufficient. Better results were achieved when both types of stimulus were applied in the same patient.

Adolescent↗
PubMedDate not supplied

Cervical carcinoma: dynamic MR imaging with a turbo-FLASH technique.

The purpose of this study was to evaluate the characteristic findings of cervical carcinoma in dynamic MR imaging with a turbo-FLASH technique and to investigate the cause of the hyperintense rim surrounding the tumor on dynamic MR images by comparing them with the pathological findings in the resected specimens. Sixty consecutive patients with cervical carcinoma were included in this study. Dynamic MR imaging was performed with the rapid administration of Gd-DTPA using the turbo-FLASH technique. After dynamic MR imaging, T1-weighted spin echo (SE) images were obtained. Dynamic patterns of the lesions were investigated from images acquired in the early and late phases of dynamic MR imaging. The causes of the hyperintense rim were investigated by comparing dynamic MR images with the pathological findings. Most of the cervical carcinomas showed higher signal intensity than normal cervical stroma in the early phase of dynamic MR imaging. The pathological findings of the hyperintense rim on dynamic MR images differed according to the time of appearance of the hyperintense rim. Dynamic MR imaging with the turbo-FLASH technique, which shows high contrast between the lesion and normal cervical stroma, should be performed before obtaining contrast-enhanced T1-weighted SE images in patients with cervical carcinoma.

Adult↗
PubMed1998

[The initial (I and II) and advanced (III and IV) stages of juvenile patellar chondromalacia. Its diagnosis by magnetic resonance using a 1.5-T magnet with FLASH sequences].

PURPOSE: Juvenile patellar chondromalacia is a common orthopedic disorder which can mimic other conditions; early diagnosis is mandatory to prevent its evolution into osteoarthrosis. In the early stages of patellar chondromalacia (I and II), the lesions originate in the deep cartilage layer and the joint surface is not affected. Arthroscopy can demonstrate joint surface changes only and give indirect information about deeper lesions. We investigated the yield of 2D FLASH MRI with 30 degrees flip angle and a dedicated coil in the diagnosis of patellar chondromalacia, especially in its early stages. MATERIAL AND METHODS: Eighteen patients (mean age: 21 years) with clinically suspected patellar chondromalacia were examined with MRI; 13 of them were also submitted to arthroscopy. A 1.5 T unit with a transmit-and-receive extremity coil was used. We acquired T1 SE sequences (TR/TE: 500-700/15/20) and 2D T2* FLASH sequence (TR/TE/FA: 500-800/18/30 degrees). The field of view was 160-180 mm and the matrix 192 x 256, with 2-3 NEX. The images were obtained on the axial plane. The lesions were classified in 4 stages according to Shahriaree classification. RESULTS: Agreement between MR and arthroscopic findings was good in both early and advanced lesions in 12/13 cases. Early lesions appeared as hyperintense focal thickening of the hyaline cartilage (stage I) or as small cystic lesions within the cartilage and no articular surface involvement (stage II). The medial patellar facet was the most frequent site. Advanced lesions appeared as articular surface ulcerations, thinning and cartilage hypointensity (stage III); stage IV lesions presented as complete erosions of the hyaline cartilage and hypointense underlying bone. CONCLUSIONS: 2D FLASH MRI with 30 degrees flip angle can show the differences in water content in the cartilage and thus permit to detect early chondromalacia lesions in the deep cartilage.

Adolescent↗
PubMed1998

Mobilization of intracellular calcium by intracellular flash photolysis of caged dihydrosphingosine in cultured neonatal rat sensory neurones.

The ability of dihydrosphingosine to release Ca2+ from intracellular stores in neurones was investigated by combining the whole cell patch clamp technique with intracellular flash photolysis of caged, N-(2-nitrobenzyl)dihydrosphingosine. The caged dihydrosphingosine (100 microM) was applied to the intracellular environment via the CsCl-based patch pipette solution which also contained 0.3% dimethylformamide and 2 mM dithiothreitol. Cultured dorsal root ganglion neurones from neonatal rats were voltage clamped at -90 mV and inward whole cell Ca2+-activated currents were recorded in response to intracellular photorelease of dihydrosphingosine. Intracellular photorelease of dihydrosphingosine (about 5 microM) was achieved using a Xenon flash lamp. Inward Ca2+-activated currents were evoked in 50 out of 57 neurones, the mean delay to current activation following photolysis was 82+/-13 s. The responses were variable with neurones showing transient, oscillating or sustained inward currents. High voltage-activated Ca2+ currents evoked by 100 ms voltage step commands to 0 mV were not attenuated by photorelease of dihydrosphingosine. Controls showed that alone a flash from the Xenon lamp did not activate currents, and that the unphotolysed caged dihydrosphingosine, and intracellular photolysis of 2-(2-nitrobenzylamino) propanediol also did not evoke responses. The dihydrosphingosine current had a reversal potential of -11+/-3 mV (n = 11), and was carried by two distinct Cl- and cation currents which were reduced by 85% and about 20% following replacement of monovalent cations with N-methyl-D-glucamine or application of the Cl- channel blocker niflumic acid (10 microM) respectively. The responses to photoreleased dihydrosphingosine were inhibited by intracellular application of 20 mM EGTA, 10 microM ryanodine or extracellular application of 10 microM dantrolene, but persisted when Ca2+ free saline was applied to the extracellular environment. Intracellular application of uncaged dihydrosphingosine evoked responses which were attenuated by photolysis of the caged Ca2+ chelator Diazo-2. Experiments also suggested that extracellular application of dihydrosphingosine can activate membrane conductances. We conclude that dihydrosphingosine directly or indirectly mobilises Ca2+ from ryanodine-sensitive intracellular stores in cultured sensory neurones.

Animals↗
PubMed1998

[Flash electroretinography and pattern-type visual evoked potentials in early glaucoma].

PURPOSE: The aim of this prospective study was to evaluate diagnostic sensitivity of flash-erg, oscillatory potentials (OPs), and pattern-visual evoked potentials (pVEP) in early glaucoma. MATERIAL AND METHODS: Erg, OPs and pVEP were registered in 416 eyes primary open angle glaucoma (120 eyes), normal tension glaucoma (137), ocular hypertension (74), glaucoma-like discs (86) in age-matched groups, by Tomey 400. RESULTS: There were no statistically significant differences between parameters of flash-erg and pVEP of examined population and control group. Significant reduction in OPs amplitude in NTG patients were found. CONCLUSIONS: Flash erg and pVEP have low diagnostic value in early glaucoma. OPs could be useful in scientific research on pathogenesis of glaucomatous neuropathy.

Adult↗
PubMed2004

Tubal sterilization and hot flashes.

A cross-sectional study was conducted among women ages 40-60 years to assess the association between tubal sterilization and the occurrence of any, moderate/severe, or daily hot flashes. Although women with tubal sterilization were more likely to report hot flashes than were nonsterilized women, this association was largely due to differences in characteristics between the women, particularly body mass.

Adult↗
PubMed1998

Menopausal-like hot flashes reported in women of reproductive age.

OBJECTIVE: To report the occurrence of menopausal-like hot flashes in women of reproductive age (18-45 years). DESIGN: Observational, prospective cohort study with a retrospective survey component. SETTING: Tertiary care premenstrual syndrome (PMS) clinic and university campus. PATIENT(S): Patients with confirmed PMS (n = 157) were compared with those with chronic menstrual cycle-related symptoms (n = 27). Women without menstrual cycle-related symptoms were solicited as controls (n = 58). INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): The frequency of episodes of chills and sweats and the magnitude of menstrual cycle-related symptoms were recorded over one cycle using the Prospective Record of the Impact and Severity of Menstrual Symptomatology (PRISM) Calendar. Characteristics of the episodes of chills and sweats were ascertained by a retrospective questionnaire. RESULT(S): In each group, the frequency of episodes of chills and sweats closely patterned the mean daily PRISM Calendar scores. At least one episode of chills and sweats was reported by 83.4% of the PMS group and 81.5% of the chronic group compared with 43.1% of the control group. The mean (+/-SD) number of episodes per cycle was 5.6 +/- 4.9 for the PMS group and 9.5 +/- 9.1 for the chronic group compared with 1.2 +/- 2.0 for the control group (the difference between all means was statistically significant). CONCLUSION(S): Episodes of chills and sweats similar to menopausal hot flashes were commonly reported by women with cyclic and chronic menstrual cycle-related symptoms.

Adolescent↗
PubMed2005

Pharmacogenetics of tamoxifen biotransformation is associated with clinical outcomes of efficacy and hot flashes.

PURPOSE: Polymorphisms in tamoxifen metabolizing genes affect the plasma concentration of tamoxifen metabolites, but their effect on clinical outcome is unknown. METHODS: We determined cytochrome P450 (CYP)2D6 (*4 and *6) and CYP3A5 (*3) genotype from paraffin-embedded tumor samples and buccal cells (living patients) in tamoxifen-treated women enrolled onto a North Central Cancer Treatment Group adjuvant breast cancer trial. The relationship between genotype and disease outcome was determined using the log-rank test and Cox proportional hazards modeling. RESULTS: Paraffin blocks were obtained from 223 of 256 eligible patients, and buccal cells were obtained from 17 living women. CYP2D6 (*4 and *6) and CYP3A5 (*3) genotypes were determined from 190, 194, and 205 patient samples and in 17 living women. The concordance rate between buccal and tumor genotype was 100%. Women with the CYP2D6 *4/*4 genotype had worse relapse-free time (RF-time; P = .023) and disease-free survival (DFS; P = .012), but not overall survival (P = .169) and did not experience moderate to severe hot flashes relative to women heterozygous or homozygous for the wild-type allele. In the multivariate analysis, women with the CYP2D6 *4/*4 genotype still tended to have worse RFS (hazard ratio [HR], 1.85; P = .176) and DFS (HR, 1.86; P = .089). The CYP3A5*3 variant was not associated with any of these clinical outcomes. CONCLUSION: In tamoxifen-treated patients, women with the CYP2D6 *4/*4 genotype tend to have a higher risk of disease relapse and a lower incidence of hot flashes, which is consistent with our previous observation that CYP2D6 is responsible for the metabolic activation of tamoxifen to endoxifen.

Adult↗
PubMed2005

Newer antidepressants and other nonhormonal agents for the treatment of hot flashes.

The reluctance to use estrogen in breast cancer survivors with hot flashes has extended to its use in healthy women since the 2002 publication of the Women's Health Initiative study. This article reviews the clinical development of nonhormonal agents as alternatives to hormonal therapy for the management of hot flashes.

Adrenergic alpha-Agonists↗
PubMed2005

[Prevalence and factors associated with hot flashes in climacteric and post-climacteric women].

A cross-sectional study was conducted on the prevalence of hot flashes and associated factors among women from 40 to 69 years old, from a population-based sample in the city of Pelotas, southern Brazil. A multi-stage sampling process was used, and data were collected through an interview and a self-applied questionnaire. A total of 879 women were included. Point prevalence and lifetime prevalence were 30.1% and 53.2%, respectively. Factors associated with hot flashes were: pre-menopausal status (RP = 2.33) and post-menopausal status (RP = 2.66); age 45-49 years (RP = 1.34) and 50-54 years (RP = 1.42); lower social class (RP = 2.16); no use of a hormonal contraception method after 40 years of age (RP = 1.40); obesity (RP = 1.39) and overweight (RP = 1.32); and not having a partner (RP = 0.80). High prevalence of this symptom indicates that health facilities should be prepared to deal with problems encountered by climacteric women.

Adult↗
PubMed1978

Corneal wick electrode for recording bright flash electroretinograms and early receptor potentials.

We developed a corneal wick electrode that is free of photovoltaic artifact when used with a bright flash strobe and is convenient for routine clinical application. The corneal wick electrode is employed for bright flash electroretinogram (ERG) recordings and for research measurements of the early receptor potential. The wick electrode gives accurate, stable, reproducible recordings with an amplitude comparable to that obtained with standard contact lens electrodes.

Action Potentials↗
PubMed1980

Bright-flash electroretinography and vitreous hemorrhage. An experimental study in primates.

Serial, bright-flash electroretinograms (ERGs) were recorded from rhesus monkey eyes before and after a standard posterior penetrating ocular injury and injection of 0.5 mL of blood into the vitreous. This procedure resulted in a progressive depression to virtual nonrecordability of the ERG during a period of several weeks, owing to a combined progressive increase in optical density and loss of retinal function. The ERG depression, however, was reversible, showing a remarkable recovery during the subsequent four to eight weeks. These findings suggest that in the presence of a recent, massive vitreous hemorrhage, a nonrecordable bright-flash ERG does not necessarily indicate a permanent loss of retinal function.

Animals↗
PubMed1999

Comparison of flash lamp pulsed-dye laser (585 nm) and conventional surgery in the delay of random dorsal rat flaps.

BACKGROUND AND OBJECTIVE: Delay is a basic surgical technique used by flap surgeons to improve the blood supply to the distal parts of a random skin flap. The aim of this study was to determine whether a scarless delay can be done by the use of the flash lamp pulsed-dye laser operating at a wavelength of 585 nm. STUDY DESIGN/MATERIALS AND METHODS: The pilot study showed that 6 J/cm(2) had a selective photothermolysis effect and therefore was chosen for testing the delay procedure on 15 rats. The percentage of flap necrosis of this group was compared to the results of 15 rats that underwent delay by surgery and 15 rats that were not treated prior to flap surgery (control group). RESULTS: Laser delay of McFarlane flaps resulted in an average of 15.5% smaller necrotic area compared to the control group (52.7% +/- 14.4% and 68.2% +/- 9.6%, respectively, P < 0.01) and was as effective as surgical delay (53.3% +/- 13.6%). CONCLUSIONS: The results indicate that the flash lamp pulsed-dye laser operating at 585 nm is effective for delaying cutaneous flaps in the rat model.

Analysis of Variance↗