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PubMed2002

[Sexual activity and contraception habits among adolescents over the last 14 years. An investigation among 9th grade pupils in the municipality of Viborg].

INTRODUCTION: The purpose of the investigation was to illustrate changes in sexual activity, the use of contraceptive methods, and age at the first coitus during the last fourteen years. MATERIAL AND METHODS: Twenty-one ninth grade classes in schools in the municipality of Viborg were asked to complete a questionnaire. Altogether 372 questionnaires were distributed and 344 pupils (92%) were entered in the investigation. Neither the teachers nor the pupils knew anything about the investigation before distribution. Identical questionnaires had been completed by the same age group in 1986 and 1993, which enabled us to compare the results and point out differences. RESULTS: We found no changes in age at the first coitus. One third of the pupils had had their first intercourse, 15% before the age of 15. Previously girls were sexually more active than boys, this difference was now equalised. Most (53%) of the experienced pupils had not had coitus in the preceding four weeks, but, compared with 1986, more of the pupils had been sexually active within the preceding week. As found in 1993, the use of condoms had increased, which was still unchanged. There was a continuing decline in the use of the pill at the first intercourse. However, the pupils changed the condoms for the pills as they became more experienced. Ten per cent of the pupils still did not use any contraception at the first intercourse. Occasional use of contraception was more common. In 1986, 75% used contraception at every intercourse, that proportion had fallen to 51% in the year 2000. DISCUSSION: Age at the first intercourse remained unchanged over the 14 years examined, and the change in contraceptional habits seen in 1993 had persisted, except that the proportion using contraception at every intercourse had decreased. The explanation for not using contraception was generally that the intercourse was unplanned. The girls were at a greater risk of unwanted pregnancies and sexually transmitted diseases, as they, more often than the boys, used unsafe methods of contraception.

Adolescent↗

PubMed1989

Adaptive realtime compensatory feedback to open the light-pupil reflex loop.

Integrity of the visual pathway is often clinically determined from response of the pupil to light. The need for more quantitative measurement of pupillary response has led engineers to investigate the light-pupil reflex with systems analysis techniques. The results have made the light-pupil reflex a model of the application of the principles of control theory to physiologic mechanisms. This analysis required that the system be rendered open loop by focusing the stimulus at the center of the pupil. Patients may not be able to restrict their head and eye movement well enough to permit the feedback loop to be rendered open loop optically. Thus, clinical applications of the technique have been limited. A means of opening the feedback loop by using a realtime deterministic autoregressive moving average prediction algorithm integrated into a computer based television pupillometer has been developed. It employs a model reference adaptive scheme to identify the physiologic system, then predicts future values of pupil area to compensate for delays in the measuring apparatus. A computer driven liquid crystal display shutter controls retinal illuminance to render the light-pupil reflex open loop. This technique reduced the mean square error of retinal illuminance by about 75% compared to uncompensated pupil responses.

Algorithms↗

PubMed1986

The pupil cycle time in Horner's syndrome.

Edge-light pupil cycle time has been introduced recently as a simple method for examining parasympathetic pupillary innervation. Since the sympathetic system is not thought to be involved in the light reflex, it was assumed that edge-light pupil cycle time would be unimpaired in lesions of the sympathetic pathways. In 12 patients with unilateral Horner's syndrome of different etiologies, the edge-light pupil cycle time was determined in both eyes. In all cases the edge-light pupil cycle time was significantly prolonged on the abnormal side. Patients with central, preganglionic, or postganglionic lesions showed the differences consistently. These data support the notion that the sympathetic system plays a role in the pupillo-dilating phase of edge-light pupil cycle time, presumably by exerting a tonic mydriatic effect. Since this tonic effect is lost in Horner's syndrome, leading to slowed redilatation, the edge-light pupil cycle time becomes prolonged. Thus, edge-light pupil cycle time may prove to be a valuable diagnostic test for Horner's syndrome.

Aged↗

PubMed1994

Attitude and knowledge of high school pupils in Holon (Israel) toward AIDS.

The study was designed to test the knowledge and attitude of pupils in three high schools with respect to AIDS. The 412 pupils who participated in the study represented three different educational institutions: an academic level school, a traditional religious school, and a vocational trade school. The standard of knowledge was found to be relatively lacking (67-75%), and there were significant differences between the three schools (P < 0.00001). There were many misconceptions concerning the symptomatology of the disease, its chronology and its prognosis. Boys were better informed than girls (P < 0.0225), and with age, the pupils' knowledge improved (P < 0.001). There were, however, no differences in the severity of the pupils' attitude towards the disease in any of the three schools (P < 0.00001). Attitudes regarding expulsion of AIDS patients from school, and moral and financial assistance varied from school to school. A most consistent factor was that pupils acquired their knowledge from the media (TV 94.66%, newspapers 89.81%), and that the medical profession contributed very little to the pupils' understanding of the disease (22.09%). Most of the pupils (92.9%) requested that prevention of this disease be incorporated as a subject into the formal teaching program of the school.

Acquired Immunodeficiency Syndrome↗

PubMed2002

Pupillary response to four concentrations of pilocarpine in normal subjects: application to testing for Adie tonic pupil.

PURPOSE: To determine the amount of pupillary constriction to four different concentrations of pilocarpine in normal human subjects and to determine if pupillary constriction correlates with bioavailability of the instilled concentrations. The amount of pupillary constriction to dilute pilocarpine is utilized as a diagnostic test for Adie tonic pupil as distinguished from a normal pupil response. DESIGN: Twenty healthy volunteers had automated binocular infrared pupillography in the dark after instillation of four different concentrations of dilute pilocarpine. Ocular penetration of eye drops was also assessed using 2% fluorescein sodium as a tracer. METHODS: Prospective institutional double-masked study of both eyes of twenty healthy volunteers, ten with brown irides, ten with blue irides, between the ages of 20-40 years. RESULTS: A pilocarpine dose-dependent curve showed decreased pupil size within 15 minutes, peaking at 30-60 minutes. No difference was noted between right and left eyes, iris color, or corneal permeability. CONCLUSIONS: Normal pupils constrict to dilute concentrations of pilocarpine (0.25% or 0.125%), but constrict insignificantly to concentrations of 0.0313% or 0.0625%. Pupil constriction with 0.0625% pilocarpine should distinguish an Adie pupil from normal. This confirms the utility of this simple office diagnostic procedure.

Adult↗

PubMed1995

Atonic pupil after cataract surgery.

We report and describe the clinical findings of three patients who developed atonic pupil after uncomplicated extracapsular cataract extraction with posterior chamber intraocular lens implantation. All patients had normally reactive pupils one day postoperatively, but after two weeks, the pupils were dilated and nonreactive to light, accommodation, and miotics. To estimate the incidence of atonic pupil after cataract surgery, we sent a survey on the frequency, clinical features, and possible etiologies of this syndrome to members of the American Society of Cataract and Refractive Surgery. Of the 567 respondents, 60% had seen at least one case of atonic pupil in the past five years; they reported a total of 1543 cases during that time. This is probably a conservative figure since many cases undoubtedly go unnoticed because of a lack of visual disturbance. We believe this condition occurs more frequently than previously reported. The atonic pupil should be recognized as a possible complication of cataract surgery that should be included in the preoperative consent form.

Aged↗

PubMed1998

Pupil involvement in patients with diabetes-associated oculomotor nerve palsy.

OBJECTIVE: To derive a reliable estimate of the frequency of pupil involvement in patients with diabetes-associated oculomotor nerve palsy. PATIENTS AND METHODS: In this prospective study, standardized enrollment criteria were employed to identify 26 consecutive patients with diabetes-associated oculomotor nerve palsy who were evaluated in a referral-based, outpatient neuro-ophthalmology practice. A pupil ruler accurate to within 0.5 mm was used to measure pupil diameters using a standardized procedure. The degree of anisocoria, if present, was recorded at each office visit until the ophthalmoplegia had resolved. Descriptive statistics were used to identify the frequency and characteristics of pupil involvement. RESULTS: Internal ophthalmoplegia occurred in 10 (38%) of 26 patients. The size of the anisocoria was 1 mm or less in most patients. None of the patients had a fully dilated unreactive pupil. CONCLUSIONS: Pupil involvement in patients with diabetes-associated oculomotor nerve palsy occurs more often than has been previously recognized, although the degree of anisocoria in any 1 patient is usually only 1 mm or less. Some characteristics of the internal ophthalmoplegia may help to distinguish diabetic ophthalmoplegia from injury of the oculomotor nerve caused by aneurysmal compression.

Aged↗

PubMed1997

Effect of cataract and pupil size on image quality with confocal scanning laser ophthalmoscopy.

OBJECTIVE: To determine the effect of pupil size and cataract on the reproducibility and image quality obtained with confocal scanning laser ophthalmoscopy. METHODS: Three image series were obtained with a confocal scanning laser ophthalmoscope (Heidelberg Retina Tomograph, Heidelberg, Germany) before and after pupillary dilation in each of 39 subjects (8 normal subjects, 5 glaucoma suspects, and 26 patients with glaucoma). The cataract density was measured with both a lens opacity meter and the Lens Opacities Classification System III system. The image quality of each image series was subjectively scored on a scale of 0 (poor) to 9 (high) by 2 independent observers who were unaware of the cataract density and pupil size during image acquisition. The image quality and reproducibility were objectively evaluated using the SD of the mean topography image of each subject. RESULTS: The mean pupil diameter in all subjects before and after dilation was 2.5 +/- 0.8 mm and 5.8 +/- 1.4 mm, respectively. After pupillary dilation, both the mean image quality score and mean SD of the mean topography image improved (from 4.5 +/- 3.5 to 7.4 +/- 2.3 and from 48.6 +/- 18.8 microns to 35.6 +/- 15.5 microns, respectively). The quality score of the images that were obtained before pupillary dilation was associated with the pupil size and density of nuclear and posterior subcapsular cataracts. The SD of the mean topography images that were obtained before pupillary dilation increased with a decreasing pupil size (P = .003) and an increasing density of the nuclear (P < .03), cortical (P = .02), and posterior subcapsular (P = .002) opacity. CONCLUSIONS: Although pupillary dilation improved the image quality in most subjects, the improvement was sometimes small. Those subjects with small undilated pupils and/or cataracts may benefit most from pupillary dilation.

Aged↗

PubMedDate not supplied

Pupil abnormalities on the first postoperative day after cataract surgery.

Most, if not all, ophthalmologists strive to achieve a round pupil after cataract surgery with posterior chamber lens implantation. The presence of pupil abnormalities and iris modifications is cosmetically undesirable and may affect the quality of postoperative vision. The pupillary motility may be changed which will in turn affect both pupillary light reflexes and pupillary dilatation during fundus examination. In this paper, we prospectively studied 2 groups of patients who underwent uncomplicated cataract surgery with posterior chamber lens implantation; 100 patients who had planned extracapsular cataract extraction (ECCE), and 130 patients who underwent phacoemulsification. On the first postoperative day, we found a 16% rate of pupil abnormalities in the group which underwent ECCE surgery while only 5.3% of the phacoemulsification group had pupil abnormalities. There were different causes in which the two groups. The most common cause of pupil abnormality after ECCE was due to iris sphincter rupture, whereas the most common cause after phacoemulsification was due to iris trauma during phacoemulsification. These pupil abnormalities are the direct consequence of factors in surgery and we suggest ways to minimize the occurrence of such abnormalities in cataract surgery.

Cataract Extraction↗

PubMed1982

A model for nonlinear stochastic behavior of the pupil.

In this paper we present new experimental results that show pupillary noise to be multiplicative in a particular fashion with greatest variance in midrange and smaller variance at high and low ranges. This confirms the finding of multiplicative noise by Stanten and Stark (1966), but modifies and extends the relationship they suggested between standard deviation and mean pupil diameter. We propose a parametric model of the iris muscle which not only describes the static characteristics of pupil response to given stimuli, but also explains its random fluctuations in terms of probability density functions. We emphasize the point that the range nonlinearity is not due to decreased gain at the extrema of the pupil range, but is operational over a wide portion of the pupillary behavioral range, hence its name--"expansive range nonlinearity". We conclude that noise amplitude, which is a function of the pupil diameter, closely parallels the changes in deterministic gain. Thus pupil noise can be simply considered as cross-talk additive Gaussian noise injected into the pupil system at midbrain level.

Humans↗

PubMed1987

A method of measuring pupil-blocking force in the human eye.

A new method of measuring pupil-blocking force in the human eye is reported. The anterior segment of the eye was photographed using a slit-lamp apparatus and the color photographs then analyzed with a digitizer for converting the optical image of the anterior eye segment into the true image using a computer. This technique permits precise estimation of the relative positions of the anterior chamber, such as pupil margins, iris root insertions, and central anteroposterior pupillary axis. Pupil-blocking force was calculated from these data according to Hook's law. There was a statistically significant difference in pupil-blocking force between normal subjects (mean +/- SD, -0.027 +/- 0.029 lambda; lambda = Young's module) and patients with primary angle-closure glaucoma (mean +/- SD, +0.134 +/- 0.068 lambda) (P less than 0.001). In patients with primary angle-closure glaucoma, during an acute attack the pupil-blocking force was markedly high. This technique for measuring pupil-blocking force will provide valuable data for the analysis of the mechanism of primary angle-closure glaucoma.

Aged↗

PubMed1997

[Cataract surgery in narrow pupil and postoperative fibrin reaction, especially after sphincterectomy].

BACKGROUND: Since increased intraoperative iris irritation can lead to increased postoperative inflammation, we are interested in postoperative reactions to several varied surgical procedures. We performed pupil stretching, iridotomy with iris suture, and partial sphincterectomy. MATERIALS AND METHODS: From January 1995 to January 1996, 100 patients (103 eyes) with narrow pupils underwent cataract surgery. In 13 eyes a iridotomy and iris suture were performed, in 28 eyes a partial sphincterectomy. In 62 eyes there was no surgical intervention after pupil stretching. Postoperative examinations were carried out in the early postoperative phase (up to 5 days postoperative) as well as 4 weeks after surgery. Fibrin reaction was classified according to 3 grades, (1) faint fibrinous threads, (II) fibrinous net, and (III) membranous fibrin exsudation. RESULTS: In the group without additional surgery there was a fibrinous reaction of grade I and II in 11 eyes. This complication occurred after iridotomy and iris suture in four cases and after sphincterectomy in four cases. While the intensity of fibrinous reaction was comparable in the first two groups, the fibrinous reaction after sphincterectomy was more intensive in one eye (grade III). However, response to intensive local antiphlogistic therapy was good. Frequency of fibrinous reaction in the three groups was statistically not significant. It should be pointed out that there was a partial restoration of pupil movements through sphincterectomy: mean pupil diameter was 4 mm, and 2.5 mm under exposure to light. Three patients had no pupillary reaction at all. CONCLUSIONS: Partial sphincterectomy facilities intraoperative manipulations of cataract surgery. Postoperative inflammatory reaction is rare and was very responsive to medical treatment. The reconstruction of pupillary movement is part of full visual function and, last but not least a round pupil is aesthetically more desirable.

Aged↗

PubMed2000

[Pupil physiology after cataract surgery].

BACKGROUND: The goal of a cataract operation is to achieve an optimal outcome, which includes a round and functioning pupil. The goal of this study was to analyze the influence of cataract operations on pupils that appear to be normal on slit-lamp examination postoperatively. PATIENTS AND METHODS: A videopupillography was performed on 47 eyes of 47 patients after phacoemulsification without complications in the first eye, and on 12 eyes of 12 patients after phacoemulsification without complications in the second eye. RESULTS: After surgery, the first eyes showed a significantly more constricted pupil compared to the non-operated eye independently of the stage of irritation. After surgery of the second eye, this was only observed under near dark conditions. CONCLUSION: Even the morphologically normal pupil shows a change in motility postoperatively. We believe that the reason for this is the mechanical manipulation of the iris during cataract operation. During this, the sensitive dilator muscle of the pupil is affected, leading to temporary or permanent changes in pupillary function. The change in motility of the contralateral, non-operated eye cannot be easily explained. The pupil size is important for the visual process and alteration of its function allows an evaluation of the quality of the operation.

Humans↗

PubMed1988

Irregular pupil cycling as a characteristic abnormality in patients with demyelinative optic neuropathy.

We used an infrared videopupillometer combined with an electronic circuit that regulated the retinal light level as a function of pupil area to assess the regularity of pupil cycling in normal subjects and in patients with known abnormalities in the pupil light reflex pathways. The light stimulus was turned on whenever pupil area exceeded a preset value. Two types of abnormalities were observed for patients with demyelinative optic neuropathy: a failure of the pupil to cycle despite a preserved pupillary response to a single light pulse; and, for those patients in whom cycling was possible, a characteristic intermittent irregularity in the amplitude of pupil cycling. These abnormalities were not seen in normal subjects or in patients with ischemic optic neuropathy, surgical lesions involving the optic chiasm, Adie's syndrome, or Horner's syndrome.

Adolescent↗

PubMed1992

The effect of pupil size on chromostereopsis and chromatic diplopia: interaction between the Stiles-Crawford effect and chromatic aberrations.

Several studies have reported that the magnitude of chromostereopsis changes as the pupil size changes. Einthoven's theory, that chromostereopsis is determined by interocular differences of monocular transverse chromatic aberration, can not easily explain this change. Therefore, several alternative hypotheses have been introduced, most notably by Vos [(1960) Vision Research, 6, 105-107], who argues that shifts in chromostereopsis with pupil size are due to decentration of the peak of the Stiles-Crawford effect (SCE) with respect to the pupil. We tested this hypothesis by measuring chromostereopsis under both scotopic (no SCE) and photopic conditions with centered and decentered artificial pupils. The results show that the SCE plays an important role in the effect of pupil size on chromostereopsis. Similar changes were also measured in monocular chromatic diplopia which supports the hypothesis that the effect of pupil size on chromostereopsis is due to monocular mechanisms.

Adult↗

PubMed2005

Cataract surgery in eyes with iridoschisis using the Perfect Pupil iris extension system.

PURPOSE: To evaluate the use of the Perfect Pupil system (Milvella Pty. Ltd.) in 3 eyes in cataract surgery with iridoschisis. SETTING: Department of Ophthalmology, University of Heidelberg, Heidelberg, Germany. METHODS: Patient 1 was an 83-year-old man with a nuclear cataract, pseudoexfoliation syndrome, and iridoschisis. He was also having systemic anticoagulation therapy. Preoperative best corrected visual acuity (BCVA) was 0.05 in the right eye and 0.08 in the left eye. Patient 2 was a 73-year-old mentally retarded man with a brunescent cataract in the right eye. Preoperative BCVA was 0.1. RESULTS: In the first patient, cataract surgery was performed under topical anesthesia in both eyes through a clear corneal incision. Intraoperative pupil size was 3.0 mm. The Perfect Pupil device was inserted manually and fixated at the iris rim, leading to pupil dilation of 6.0 mm. Uneventful cataract surgery was performed without damage to the iris. Hydrophobic acrylic foldable intraocular lenses (IOLs) were implanted with forceps. Postoperative BCVA was 0.5 in the right eye and 0.4 in the left eye. The second patient was operated on under general anesthesia. Pupil dilation was successfully achieved. The brunescent cataract was removed and a hydrophobic acrylic IOL was implanted with an injector, resulting in postoperative uncorrected visual acuity of 0.3. CONCLUSION: In iridoschisis patients, there is risk of aspiration of iris fibers during cataract surgery. In these 2 patients, this was prevented using the Perfect Pupil system.

Aged↗

PubMed2006

Effects of pupil stretch technique during phacoemulsification on postoperative vision, intraocular pressure, and inflammation.

PURPOSE: To determine whether pupil stretch during phacoemulsification affects postoperative best corrected visual acuity (BCVA), intraocular pressure (IOP), and inflammation compared with results in patients without pupil stretch. METHODS: A retrospective analysis of 115 eyes that had pupil stretch during phacoemulsification (study group) and 125 eyes without pupil stretch (control group) was performed with a minimum of 12 months follow-up. Single-factor analysis of variance and 2-tailed homoscedastic t tests were used for statistical analysis. RESULTS: The mean preoperative logMAR equivalent BCVA was 0.5 +/- 0.3 (SD) in the study group and 0.6 +/- 0.4 in the control group. The mean preoperative IOP was 16.2 +/- 4.1 mm Hg in the study group and 16.0 +/- 3.5 mm Hg (control group). There was no statistically significant difference at postoperative follow-up of 1 year in BCVA or IOP between the 2 groups (1 year BCVA 0.2 +/- 0.2 [study group], 0.2 +/- 0.2 [control group] [P<.1]; IOP 14.5 +/- 3.5 mm Hg and 14.7 +/- 3.3 mm Hg, respectively [P<.7]). There was no significant difference in the number of glaucoma medications required for glaucoma patients preoperatively and postoperatively between the 2 groups (P<.5). Complications were rare, and there was no significant difference in the complications (ie, iritis, hyphema, cystoid macular edema, epiretinal membrane formation) between the 2 groups at 1 year. CONCLUSION: Pupil stretch during phacoemulsification was not associated with a statistically significant difference in BCVA, IOP, inflammation, or other complications postoperatively compared with results in the control group without pupil stretch.

Antihypertensive Agents↗

PubMed2006

Burst-shot infrared digital photography to determine scotopic pupil diameter.

PURPOSE: To evaluate the usefulness of infrared digital photography for determining scotopic pupil size by comparing infrared digital photography with a Colvard pupillometer (Oasis Medical). SETTING: Department of Ophthalmology, Ajou University School of Medicine, Suwon, Korea. METHODS: Scotopic pupil size in 50 eyes of 25 healthy individuals was measured with a Colvard pupillometer and a digital camera (DSC-F828) using infrared burst shots after 5 minutes of dark adaptation. Measurements were performed by 2 independent examiners (E1 and E2). The digital photograph images were read using the ruler function of Adobe Photoshop 7.0 by 2 independent readers (R1 and R2). Agreement and repeatability were analyzed using the comparison method described by Bland and Altman. RESULTS: The mean scotopic pupil diameter measured using the Colvard pupillometer was 6.69 mm +/- 0.78 (SD) (E1) and 6.70 +/- 0.71 mm (E2). The mean scotopic pupil diameter measured from the digital photograph images was 6.67 +/- 0.75 mm (E1) and 6.66 +/- 0.78 mm (E2). The mean difference between E1 and E2 with both devices was small; however, the result with the infrared digital camera was marginally smaller than with the Colvard pupillometer. The limits of agreement were -0.01 +/- 0.70 mm with the Colvard pupillometer and 0.01 +/- 0.20 mm with the digital photograph image. The digital photograph image showed better agreement. The coefficient of interrater repeatability was smaller for the digital photograph image (0.39) than for the Colvard pupillometer (0.70). CONCLUSIONS: Scotopic pupil measurement using an infrared digital camera with a burst shot had good agreement with the Colvard pupillometer and better repeatability. The infrared digital camera is less expensive, and pupil unrest can be overcome by taking serial images.

Adult↗