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Results for “OPHTHALMOSCOPY”

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PubMed1993

The effect of formal instruction in ophthalmoscopy on medical student performance.

Ophthalmoscopy is an essential part of a complete clinical examination of a patient. However specific formal instruction in fundoscopy is rarely given to medical students. We decided to determine the value of explicit teaching of ophthalmoscopy and devised and validated a rating scale for assessing performance which was used to evaluate 29 first year clinical medical student volunteers at St. Bartholomew's Hospital Medical College, before and after formal instruction in fundoscopy. The competence of this group at ophthalmoscopy was then compared to the rest of their year (109 medical students) during the objective structured clinical end-of-year examination. Students formally instructed in ophthalmoscopy showed an improved score after instruction (from 53% to 77%). They also performed better at fundoscopy than the rest of their year (mean average score 64%), when tested 2 months later, suggesting persistence of the training effect. However as a group they performed no better than their peers at clinical skills other than ophthalmoscopy. We suggest that as fundoscopy is such an important clinical skill, medical students should be given specific teaching, preferably in their ophthalmology firm attachment, as we have shown that it results in a persistent improvement in performance.

Clinical Competence↗

PubMed2006

Impact of retinopathy of prematurity screening examination on cardiorespiratory indices: a comparison of indirect ophthalmoscopy and retcam imaging.

PURPOSE: To compare the impact of retinopathy of prematurity (ROP) screening examination between a digital fundus camera and conventional binocular indirect ophthalmoscopy (BIO) using cardiorespiratory indices as a measure of distress. DESIGN: Prospective comparative (nonrandomized) interventional study. PARTICIPANTS: Eighty-six preterm infants with a birth weight of < or =1500 g or gestational age of < or =32 weeks and undergoing ROP screening were included. METHODS: Retinopathy of prematurity screening examination with BIO or the digital fundus camera was performed. Cardiovascular indices were recorded before, during, and 1 hour after examination. Race, birth weight, gender, twin status, duration of the examination, gestational age, and postconceptual age were recorded. MAIN OUTCOME MEASURES: Heart rate (HR), oxygen saturation, respiratory rate (RR), and mean blood pressure (BP). RESULTS: Thirty-four infants underwent indirect ophthalmoscopy, whereas 52 underwent digital fundus camera examination. The increase in HR and RR was significantly higher in the indirect ophthalmoscopy group than in the digital fundus camera group (P<0.05). There was a significant increase in HR and mean BP during examination in both groups (P<0.05). No clinically significant response persisted at 1 hour. Digital fundus camera examination took significantly longer (P<0.001). CONCLUSIONS: Screening for ROP with a digital fundus camera is associated with a significantly lower stress-related response than conventional indirect ophthalmoscopy.

Blood Pressure↗

PubMedDate not supplied

The value of ophthalmoscopy in the diagnosis of arterial hypertension in patients with ischemic brain disease.

Beside dyslipoproteinemia, one of the key risk factors for the onset of brain atherosclerosis, as well as ischemic brain disease (IBD) is arterial hypertension. Significant number of patients is not aware of their hypertension, and a paradoxical blood pressure decrease can occur at the onset of IBD, due to the failure of autoregulation mechanisms. Likewise, valid anamnestic data can not frequently be obtained due to difficulties in communication with patients. Regarding these facts, our hypothesis was that ophthalmoscopy in patients with IBD had the greatest sensitivity in the diagnosis of hypertensive disease, its duration and severity. For that reason, the purpose of this study was to determine the significance of ocular fundus examination in those patients with IBD who were not aware of their hypertension, or the high blood pressure was not registered at the admission. Study comprised 140 IBD patients selected upon the following criteria: ophthalmoscopy was performed by the same ophthalmologist, and IBD was diagnosed according to clinical criteria and by brain computerized tomography. Results of the study demonstrated that 26 (18.6%) patients, although not aware of having hypertensive disease, had grade I hypertonic fundus, 14 (10%) had grade II, and 8 (5.5%) had grade III hypertonic fundus, which indicated the high sensitivity of ophthalmoscopy in the diagnosis of hypertensive disease, as well as its duration and severity. This is particularly important in patients with negative history of hypertension, and also suggests the significance of routine ophthalmoscopy in normotensive patients.

Aged↗

PubMed1998

Practical application of the European Field Guide in screening for diabetic retinopathy by using ophthalmoscopy and 35 mm retinal slides.

The Welsh Community Diabetic Retinopathy Study was designed to assess the effectiveness of the Field Guide Book for screening for diabetic retinopathy in Europe. A community-based sample (prevalence 2%) of diabetic patients was recruited from four general practices. Standardised training and equipment were provided. All patients were invited to attend practice-based screening sessions on two occasions over 3 years (phases 1 and 2). After mydriasis, clinical ophthalmoscopy was performed by a study optometrist and general practitioners (GPs). 2 x 45 field 35 mm retinal slides were obtained according to EURODIAB protocol. Anonymised slides were assessed by GPs, diabetologists and the optometrist. All the findings were graded externally (reference standard). In phase 2 community optometrists also performed ophthalmoscopy and assessed photographs. For detecting sight threatening diabetic retinopathy using ophthalmoscopy, GPs achieved a sensitivity of 65.7%, specificity 93.8% and positive predictive value (PPV) 65.7%. Community optometrists achieved a sensitivity of 82.2% with a PPV of 50.7%; the study optometrist 79.2 and 55.9%, respectively. The use of 35 mm slides improved sensitivity for the detection of sight threatening retinopathy to 87.3, 91.1 and 97.2% for GPs, community optometrists and the study optometrist, respectively. PPV fell to 51.2% for GPs, 40.6% for community optometrists, but increased to 58.8% for the study optometrist. Diabetologists achieved a sensitivity of 88.7% and a PPV of 65.6%. It is concluded that the European field guide is an effective tool for screening for retinopathy in clinical practice.

Confidence Intervals↗

PubMed1989

Usefulness of ophthalmoscopy in mild to moderate hypertension.

A panel of two physicians and two ophthalmologists examined 25 patients with untreated essential hypertension by direct ophthalmoscopy and assessment of fundal photographs; daytime ambulatory sphygmomanometric blood pressure monitoring, estimation of left ventricular mass by electrocardiography and two-dimensional echocardiography, and measurement of urinary microalbumin excretion were also carried out. No relation was found between blood pressure determined by clinic or ambulatory sphygmomanometry and retinopathy. The retinal features sought on fundal photographs were the percentages of arteriovenous crossings with venule nipping, venule deviation, or attenuation of venular light reflex. The ratio of arteriolar to venular diameter was measured. Only focal narrowing of arterioles was associated with higher blood pressure. There was no independent relation between retinal features and age, measures of left ventricular mass, or urinary microalbumin excretion. Assessment of arteriovenous crossing abnormalities by direct ophthalmoscopy was subject to wide variability among the panel members. Direct ophthalmoscopy was not clinically useful in the assessment of mild to moderate hypertension, whereas urinary microalbumin excretion correlated strongly with clinic blood pressure.

Adult↗

PubMed1985

Diabetic retinopathy as detected using ophthalmoscopy, a nonmydriatic camera and a standard fundus camera.

The study was performed to evaluate whether the severity of diabetic retinopathy as assessed by three alternative methods was concordant with the severity of retinopathy as determined from 30 degrees stereoscopic photographs. The three methods were direct ophthalmoscopy through an undilated pupil, nonstereoscopic 45 degrees retinal photography through a pharmacologically undilated pupil and nonstereoscopic 45 degrees photography through a dilated pupil. A single 45 degrees photograph centered between the disc and fovea was taken and direct ophthalmoscopy was performed on 99 persons prior to pharmacological dilation of the pupil. After dilation, another 45 degrees photograph was taken of the same field, as well as 30 degrees stereoscopic color photographs of DRS fields 1, 2 and 4 (modified). Corresponding photographic fields were graded by masked, trained graders for the severity of retinopathy and for the presence of specified diabetic lesions using the Modified Airlie House Classification scheme. For three levels of severity of retinopathy (none, nonproliferative or proliferative) exact agreement between direct ophthalmoscopy and grading of retinopathy from stereoscopic photographs taken with the standard 30 degrees camera was 54.3% (n = 94). For four levels of severity of retinopathy (none, microaneurysms only, all other nonproliferative retinopathy and proliferative retinopathy), exact agreement between gradings of retinopathy of the 45 degrees photographs taken through undilated pupils and 30 degrees photographs taken through dilated pupils was 82.5% (n = 63); and for 45 degrees photographs and 30 degrees photographs taken through dilated pupils it was 86.5% (n = 74). These data suggest that 45 degrees nonstereoscopic fundus photographs, when graded according to a standard classification scheme, provide reasonably reliable photographic representation of the severity of retinopathy when broad overall categories are used.

Adolescent↗

PubMed2001

Scanning laser ophthalmoscopy for early diagnosis of vitreoretinal interfase syndrome.

PURPOSE: To describe the angiographic signs found using scanning laser ophthalmoscopy for the early diagnosis of vitreoretinal interface syndrome. This method is useful to visualize the inner retinal layers, being more sensitive than fundus biomicroscopy. MATERIAL: 61 patients with vitreoretinal interfase syndrome were evaluated. All of them had evidence of this disease using scanning laser ophthalmoscopy but four patients were referred without diagnosis of vitreoretinal interfase syndrome. These patients showed no biomicroscopic signs and diagnosis was made with SLO. METHODS: Confocal scanning infrared laser ophthalmoscope (Heidelberg Retinal Angiograph assembled by Heidelberg Engineering). This SLO uses an infrared diode laser source of 795 nm. CONCLUSION: Patients included were referred with another diagnosis and with this method the correct diagnosis was made. In conclusion scanning laser ophthalmoscopy allows early diagnosis of this pathology for follow-up and treatment.

Fluorescein Angiography↗

PubMed2003

The effectiveness of screening for diabetic retinopathy by digital imaging photography and technician ophthalmoscopy.

AIMS: To evaluate the introduction of a community-based non-mydriatic and mydriatic digital photographic screening programme by measuring the sensitivity and specificity compared with a reference standard and assessing the added value of technician direct ophthalmoscopy. METHODS: Study patients had one-field, non-mydriatic, 45 degrees digital imaging photography prior to mydriatic two-field digital imaging photography followed by technician ophthalmoscopy. Of these patients, 1549 were then examined by an experienced ophthalmologist using slit lamp biomicroscopy as a reference standard. The setting was general practices in Gloucestershire. Patients were selected by randomizing groups of patients (from within individual general practices) and 3611 patients were included in the study. Patients for reference standard examination were recruited from groups of patients on days when the ophthalmologist was able to attend. The main outcome measure was detection of referable diabetic retinopathy (DR) as defined by the Gloucestershire adaptation of the European Working Party guidelines. RESULTS: For mydriatic digital photography, the sensitivity was 87.8%, specificity was 86.1% and technical failure rate was 3.7%. Technician ophthalmoscopy did not alter these figures. For non-mydriatic photography, the sensitivity was 86.0%, specificity was 76.7% and technical failure rate was 19.7%. CONCLUSIONS: Two-field mydriatic digital photography is an effective method of screening for referable diabetic retinopathy. Non-mydriatic digital photography has an unacceptable technical failure rate and low specificity.

Adolescent↗

PubMed2002

The usefulness of ophthalmoscopy in risk evaluation of hypertensive patients.

OBJECTIVES: The main objective was to assess whether systematic ophthalmoscopy in the baseline evaluation of hypertensive patients results in a change in the therapeutic attitude as a result of the discovery of target organ damage. A secondary objective was to find the relationship between fundus lesions and other target organ manifestations in patients with hypertension. RESULTS: 73.6% of the patients studied had damage to the optic fundus, 35% of the patients had fundus lesions attributable to hypertension, 21% of patients (p < 0.001) (JNC-VI) and 15.8% (p < 0.001) (WHO/ISH) changed group of risk. Patients who were more likely to change group of risk after ophthalmoscopy were those with moderate hypertension (Grade II). Patients with a level of creatinine <85 micromol/l (WHO/ISH and JNC-VI), female and middle-aged patients (WHO/ISH) and patients older than 63 (JNC-VI) were also more likely to change groups. Hypertension grades II/III, creatinine >85 micromol/l and body mass index increase the risk of fundus lesions. Females are less at risk and alcohol intake seems to have a protective effect. CONCLUSION: Ophthalmoscopy in the baseline evaluation of patients with hypertension permits a better stratification of risk.

Aged↗

PubMed1999

Fundus magnification produced during direct ophthalmoscopy of the corrected eye.

The clinical significance of fundus magnification produced during direct ophthalmoscopy of the corrected eye has not been fully established. Based on paraxial ray tracing, fundus magnification (M) can be defined by a simple equation, M = (K'/4) x (Fs/K), where K' is the dioptric axial power of the eye, Fs is the correcting thin lens power and K is the ocular ametropia. Refractive myopes produce greater fundus magnification than axial myopes, whereas refractive hyperopes produce lower fundus magnification than axial hyperopes. If we assume 15 x fundus magnification as our standard magnification for an emmetropic reduced eye, then wearing glasses or putting the focusing lens at or close to the anterior focus of the eye is able to achieve the standard magnification for axial myope and axial hyperope, whereas wearing contact lenses is able to achieve the standard magnification for refractive myope and refractive hyperope. Vertex distance has greater influence on fundus magnification produced during direct ophthalmoscopy than other funduscopic techniques. In conclusion, the newly defined formula has clinical applications during direct ophthalmoscopy.

Eyeglasses↗

PubMed2004

Ocular fundus images by scanning laser ophthalmoscopy in a patient with enhanced S-cone syndrome.

PURPOSE: To present ocular fundus images in a patient with enhanced S-cone syndrome by scanning laser ophthalmoscopy. A 34-year-old Japanese woman whose parents were consanguineous showed mismatched electroretinographic responses to photopically balanced single-flash stimuli, with a larger signal to blue light than to red light. The central macula lacked a foveal reflex, and the surface was dull. Yellowish flecks and retinal pigment epithelium atrophy were evident in a ring at and around the vascular arcades. Faint black pigmentation was deposited in the mid peripheral retina. METHODS: The ocular fundus of the patient was observed by scanning laser ophthalmoscopy with the use of an argon blue laser (wavelength, 488 nm), a helium-neon laser (633 nm), and an infrared laser (780 nm). RESULTS: The argon blue laser showed numerous black spots of pigment, which were observed as faint pigmentation by conventional ophthalmoscopy. The spots were more enhanced with the argon blue laser than with the helium-neon laser. The white spots, which corresponded to the yellowish flecks in a ring at and around the vascular arcades, were more enhanced with the helium-neon laser than with the argon blue or infrared laser. Hypopigmentation of the retinal pigment epithelium was best shown with the infrared laser. CONCLUSION: An abnormality of the retinal structure in enhanced S-cone syndrome may exist in the inner and outer retinal levels, in at least some patients.

Adult↗

PubMed1999

Agreement of measurement of parapapillary atrophy with confocal scanning laser ophthalmoscopy and planimetry of photographs.

PURPOSE: To evaluate whether parapapillary atrophy can be measured interactively using confocal scanning laser ophthalmoscopy. METHODS: For 36 patients with open-angle glaucoma or suspected of having glaucoma, confocal scanning laser ophthalmoscopy of the optic nerve head was performed using the Heidelberg Retina Tomograph (HRT; Heidelberg Engineering, Heidelberg, Germany). Alpha and beta zones of parapapillary atrophy were plotted independently by two examiners on HRT images before and after reviewing optic disc photographs. These data were compared with planimetric measurements obtained from analyzing the disc photographs. RESULTS: Before viewing the disc photographs, assessment using the HRT images correlated better with the beta zone than alpha zone planimetric measurements. If the HRT images were evaluated while simultaneously viewing disc photographs, correlation coefficients increased for both examiners 1 and 2. Interobserver and intraobserver reliability were 0.431 and 0.802, respectively, for alpha zone, and 0.882 and 0.948, respectively, for beta zone. CONCLUSION: Parapapillary atrophy can be estimated with confocal scanning laser ophthalmoscopy. Correlation with planimetric measurements is best if conventional optic disc photographs are simultaneously viewed. Intraobserver and interobserver reliability are higher for beta zone than for alpha zone.

Adult↗

PubMed1992

Ophthalmoscopy versus fundus photographs for detecting and grading diabetic retinopathy.

Reported here is the agreement between three examination methods chosen to detect and grade diabetic retinopathy in 124 subjects with type II (noninsulin-dependent) diabetes mellitus. These three examination methods include ophthalmoscopy (indirect and direct) by a retina specialist, seven standard field fundus photographs read by the same retina specialist, and the same photographs read by a trained photographic grader at the Fundus Photograph Reading Center. For the 59 subjects examined with all three methods, these results indicated fair to good (kappas, 0.69-0.84) agreement between the retina specialist's and trained grader's reading of photographs, fair to good (kappas, 0.58-0.79) agreement between the retina specialist's ophthalmoscopic findings and the specialist's reading of photographs, and fair (kappas, 0.49-0.62) agreement between the retina specialist's ophthalmoscopic findings and the trained grader's reading of fundus photographs. Analysis of the disagreements confirmed earlier reports that ophthalmoscopy misses approximately 50% of eyes with microaneurysms only. Other disagreements resulted from the trained grader's overreading photographs of eyes with lesions simulating diabetic retinopathy. Of the 393 total subjects (diabetic and nondiabetic) in this study, such lesions were seen with ophthalmoscopy in six eyes of six subjects (2.4% of diabetic patients and 1.1% of nondiabetic subjects). The authors believe at least one definite retinal microaneurysm should be present in one eye before establishing the diagnosis of diabetic retinopathy in diabetic patients.

Aged↗

PubMedDate not supplied

[Evolution of threshold retinopathy of prematurity after argon laser treatment under indirect ophthalmoscopy].

BACKGROUND: We undertook this study to evaluate the long-term effects of threshold retinopathy of prematurity (ROP) treatment using Argon laser under indirect ophthalmoscopy, as well as to analyze ocular diseases in those patients. METHODS: This is a descriptive, observational, longitudinal and prospective study carried out from March 1991 to February 2005, including patients with threshold retinopathy of prematurity for treatment using Argon laser under indirect ophthalmoscopy. Related ocular diseases were also reported. Descriptive statistics were applied. RESULTS: Follow-up was maintained for 14 years, 6.50 +/- 1.39 (CI 95%, p < 0.05), and 170 patients were studied. Weight was 1216.50 +/- 152.03 g (CI 95%, p < 0.05). Retinopathy was not present in 42% (72), in stage I-III, 46% (78), and threshold stage, 12% (20). Forty eyes were treated with Argon laser. After treatment, no progressive disease was found in 92.75%. We found high myopia in 20%, macular displacement 7.5%, strabismus 35%, retinal detachment (5%), optical nerve atrophy 5%, and ocular atrophy 5%. CONCLUSIONS: We were able to demonstrate that Argon laser treatment under indirect ophthalmoscopy has been effective in the control of threshold disease. The most important related ocular diseases were strabismus and myopia. Long-term monitoring has permitted us to initiate timely treatment for ocular diseases related to prematurity.

Argon↗

PubMed1993

Screening for diabetic retinopathy in a clinical setting: a comparison of direct ophthalmoscopy by primary care physicians with fundus photography.

BACKGROUND: Type II diabetes mellitus is a major health problem among Native Americans, and diabetic retinopathy is a frequent complication of this disease. Screening for retinopathy can identify early disease and prevent major vision loss, but the most cost-effective screening method has not yet been determined. METHODS: In a rural clinic that served more than 400 Native Americans with diabetes, we compared the accuracy of referrals made based on two screening methods: ophthalmoscopy by trained primary care physicians and seven-view nonstereoscopic, mydriatic fundal photography read by two general ophthalmologists and a retinal specialist. Patients in whom abnormal findings were detected by either screening method were then referred to a general ophthalmologist for further evaluation. RESULTS: Two hundred forty-three examinations were performed and 83 referrals made. Both screening methods had high sensitivity for referring patients with retinopathy that required treatment or follow-up sooner than 1 year (100% for direct ophthalmoscopy by primary care physicians, 94% for the general ophthalmologist photography readers, and 100% for the retinal specialist reader). The calculated costs of screening by direct ophthalmoscopy and by retinal photography were 64% less and 44% to 35% less, respectively, than the cost of yearly ophthalmological examinations by ophthalmologists. CONCLUSIONS: Careful screening for treatable diabetic eye disease by trained primary care physicians proved to be a clinically acceptable, cost-effective strategy. Screening methods for diabetic retinopathy should be evaluated based on the absolute sensitivity, specificity, and predictive values of their ability to correctly refer patients rather than their diagnostic accuracy.

Cost-Benefit Analysis↗

PubMed1994

Reproducibility of retinal nerve fiber layer evaluation by dynamics scanning laser ophthalmoscopy.

Scanning laser ophthalmoscopy is a laser-based image acquisition technique, which greatly improves the quality of the examination of the fundus and the retinal nerve fiber layer. To assess retinal nerve fiber layer imaging by scanning laser ophthalmoscopy and evaluate intra- and interobserver reproducibility in the classification of retinal nerve fiber layer defects, three independent observers evaluated on two separate occasions the videotaped images of 150 eyes of 80 consecutive patients with ocular hypertension or glaucoma. Ophthalmoscopy was performed using argon blue light (488 nm), confocal apertures of 3 to 1 mm, and 40-degree and 20-degree field angles. Of 150 eyes, 20 (13.3%) were excluded from the study because of the poor quality of the images (clinically significant cataract or myopic peripapillary atrophy). The retinal nerve fiber layer was evaluated qualitatively according to a standard classification: normal pattern, slit, wedge, and diffuse defects. Intraobserver reproducibility, evaluated by kappa statistic, was excellent (> or = 0.75): observer A = 0.78 (95% confidence limits, 0.67-0.88); observer B = 0.84 (95% confidence limits, 0.72-0.96); and observer C = 0.79 (95% confidence limits, 0.67-0.91). Interobserver reproducibility was also excellent in all cases: observers A-B = 0.84 (95% confidence limits, 0.71-0.98); observers A-C = 0.76 (95% confidence limits, 0.65-0.87); and observers B-C = 0.80 (95% confidence limits, 0.69-0.92). Kappa values ranged between 0.59 and 0.69 for intraobserver reproducibility and between 0.55 and 0.69 for interobserver reproducibility when using only those eyes in which abnormalities were noted by at least one observer.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1998

Imaging the microvasculature of choroidal melanomas with confocal indocyanine green scanning laser ophthalmoscopy.

OBJECTIVE: To image the microvasculature of choroidal melanoma with a new confocal scanning laser ophthalmoscope. METHODS: Eighteen consecutive patients, each with a unilateral choroidal melanoma, were examined prospectively. Indocyanine green angiography was performed with a new confocal scanning laser ophthalmoscope that enabled serial optical sectioning through the tumor. Two additional patients were studied with indocyanine green angiography and confocal scanning laser ophthalmoscopy just before enucleation for posterior choroidal melanomas. The histologic identification of microvasculature patterns was compared with the angiograms for these patients. RESULTS: In the series of 18 patients, 16 (89%) indocyanine green angiograms with optical sectioning revealed tubular structures within the melanoma that were identified as tumor vessels based on their angiographic appearance. The microvasculature patterns identified by indocyanine green angiography correlated well with the histologic appearance of these microvasculature patterns in both patients for whom histologic verification was available. CONCLUSIONS: This preliminary study suggests that indocyanine green angiography with confocal scanning laser ophthalmoscopy images the microvasculature of choroidal melanomas and may be capable of detecting microvasculature patterns that have been shown to be prognostically significant from histopathological studies.

Adult↗

PubMed1989

Screening for mouse retinal degenerations. I. Correlation of indirect ophthalmoscopy, electroretinograms, and histology.

Mice with hereditary retinal degeneration have provided excellent models for human disease of the biochemical and physiological events occurring in retinal degeneration. Since a number of mouse models are available for other human conditions, more mouse retinal degenerations would be expected to be known; however, finding new models has proved difficult since the search has usually involved laborious histologic screening. We applied the clinical technique of indirect ophthalmoscopy to screen mice for retinal degeneration and then used electroretinography and histology to determine whether true retinal degeneration was present. A Dawson-Trick-Litzkow microfiber corneal electrode was used to record the electroretinogram since the fiber does not occlude the pupil in these small eyes. Normal control values were developed. As an example of the success of the technique, one strain, lethal spot (ls) on indirect ophthalmoscopy appeared to have a retinal degeneration, but these mice had a normal electroretinogram indicating a primary optic atrophy. Likewise, one ls heterozygote that was tested as a control animal and was not suspected of having a retinal degeneration had an abnormal electroretinogram and peripheral retinal degeneration.

Animals↗