Hypercapnia invokes an acute loss of contrast sensitivity in untreated glaucoma patients.

BACKGROUND/AIM: It is widely accepted that hypercapnia results in increased retinal, choroidal, and retrobulbar blood flow. Reports of a visual response to hypercapnia appear mixed, with normal subjects exhibiting reduced temporal contrast sensitivity in some studies, while glaucoma patients demonstrate mid-peripheral visual field improvements in others. This suggests that under hypercapnic conditions a balance exists between the beneficial effects of improved ocular blood flow and some other factor such as induced metabolic stress; the outcome may be influenced by the disease process. The aim of this study was to evaluate the contrast sensitivity response of untreated glaucoma patients and normal subjects during mild hypercapnia. METHODS: 10 previously untreated glaucoma patients and 10 control subjects were evaluated for contrast sensitivity and intraocular pressure while breathing room air and then again during mild hypercapnia. RESULTS: During room air breathing, compared with normal subjects, glaucoma patients had higher IOP (p = 0.0003) and lower contrast sensitivity at 3 cycles/degree (cpd) (p = 0.001). Mild hypercapnia caused a significant fall in contrast sensitivity at 6, 12, and 18 cpd (p < 0.05), only in the glaucoma group. CONCLUSION: Glaucoma patients with early disease exhibit central vision deficits as shown by contrast sensitivity testing at 3 cpd. Hypercapnia induces further contrast loss through a range of spatial frequencies (6-18 cpd) which may be predictive of further neuronal damage due to glaucoma.

Board certification in optometry.

BACKGROUND: In keeping with current expectations in the health care community, the purpose of the American Board of Optometric Practice (ABOP) is to enhance the quality of optometric care available to the public by fostering continued competence for practitioners through administering education and examinations for certification and re-certification. The formation of ABOP makes possible for the first time a board certification process for optometrists. METHODS: The optometry model for board certification and recertification emphasizes the breadth of the profession. ABOP certification will be accomplished through a combination of examinations and high-quality, tested Board Certified Continuing Education (BCCE). Specific requirements for practitioners at various stages of their careers are presented. RESULTS: Board certification provides one important mechanism for an optometrist to demonstrate commitment to quality, professionalism, and ongoing clinical competence. The optometrist benefits from high-quality continuing education designed for timeliness, importance, and breadth. The public benefits by the enhancement of continued competence within the optometric profession. Health care agencies benefit by being able to recognize providers who have elected to demonstrate their qualifications through certification. CONCLUSIONS: Through board certification, optometrists will be able to demonstrate their commitment to maintaining clinical competence through a nationally uniform program, and they will be able to comply with standards that are generally recognized and required throughout the health care community.

Clinical description and review of migraine aura without headache.

BACKGROUND: Migraine aura without headache (MAWOH) is a type of migraine that seems to be reported more frequently in ophthalmic than neurologic or general medical practice. The clinical characteristics of this condition are described relative to its relationship with other forms of migraine, patient age, gender distribution, laterality, personal or family history, visual aura, and precipitating factors. As a result of its prevalence, it is a condition with which every optometrist and ophthalmologist should be familiar. Since MAWOH is a common cause of photopsia and transient vision loss, it is also important to consider it in the differential diagnosis of these conditions-especially in older patients. METHODS: The clinical investigations of MAWOH by prospective and retrospective case series are reviewed. This review includes an analysis by study of the number of patients, migraine history, and type of visual symptom. Comparison of clinical characteristics is used to distinguish MAWOH from other types of migraine. CONCLUSION: Migraine aura without headache is a type of migraine that is reported frequently in ophthalmic practice. Because it is related to photopsia and/or transient vision loss, specific clinical procedures should be performed to assist in the differential diagnosis of these conditions.

Differential diagnosis of common etiologies of photopsia.

BACKGROUND: Photopsia is a relatively common symptom reported by patients in primary eye care settings. Although there are many possible etiologies, photopsia (light flashes) is usually associated with one of the following: (1) posterior vitreous detachment, (2) migraine with aura, (3) migraine aura without headache, and (4) retinal break or detachment. Each of these clinical conditions has symptoms and physical findings that will usually render the diagnosis apparent. METHODS: It is important from a clinicolegal standpoint that specific procedures be performed to differentially diagnose the responsible condition and deliver appropriate follow-up care.

The photic sneeze response: a descriptive report of a clinic population.

BACKGROUND: The prevalence of the photic sneeze response (PSR) as well as other characteristics have been studied in selected populations. However, the PSR has not been investigated in a general eye care patient population. This study was performed in an attempt to characterize the epidemiologic, descriptive, and demographic aspects of the photic sneeze response among patients attending for primary eye care. METHODS: A questionnaire on demographics, risk factors, and triggering stimuli was distributed to 500 consecutive patients presenting for a general eye examination at an academic health center optometry clinic. RESULTS: Three hundred and sixty-seven of 500 questionnaires were returned (73.4%). Among this sample 33% were self-recognized photic sneezers with the majority being females (67%) and Caucasian (94.3%). Statistically significant correlations were found between the presence of photic sneezing and the presence of a deviated nasal septum and a non-significant association was found with tobacco use. Uniform frequency of sneezing does not occur in response to light stimulus; only 12.3% of sneezers responded consistently to sunlight exposure. The majority of sneezers (90.7%) responded with three or fewer sneezes. The interval between successive sneezes was fewer than 19 seconds in 85% of respondents. Fewer than 27% of respondents were able to recall a parent who exhibited a sneeze response. CONCLUSIONS: The PSR is not an uncommon phenomenon. Systemic associations with the PSR are as diverse as deviated nasal septum and tobacco use. Results suggest that there may be a threshold level of light or frequency of light exposure which produces the response and that more patients may acquire the response than inherit it.

Safety and efficacy of loteprednol etabonate for treatment of papillae in contact lens-associated giant papillary conjunctivitis.

Loteprednol etabonate (LE) is a new corticosteroid based on the "soft drug" concept. Contact lens-associated giant papillary conjunctivitis (GPC) was studied as a model for the anti-inflammatory effect of LE. Patients with bilateral GPC were enrolled in a multicenter, randomized, double-masked, placebo-controlled, parallel group comparison of loteprednol etabonate 0.5% ophthalmic suspension and the LE vehicle (placebo). Patients were instructed to instill 1 drop of the test medication into each eye 4 times daily for 4 weeks, and follow-up examinations occurred on Days 2 or 3, 7, 14, 21, and 28 of masked therapy. Of 113 patients enrolled, 110 patients (LE = 55; placebo = 55) completed the study as planned. Patients receiving LE demonstrated significant reduction in the primary ocular signs of GPC (papillae, p < 0.001) and were rated better in the Investigator's Global Assessment (p = 0.017). LE did not elevate intraocular pressure during the study, and ratings for bulbar conjunctival injection and the Patient Opinion Assessment demonstrated statistical trends that favored treatment with LE. LE was well tolerated and was clinically effective for the treatment of GPC.

What role will residency education take in the profession by the year 2000?

Residency education has enjoyed relatively slow but steady growth since its inception in the mid-1970s. A certain segment of recent graduates consider graduation from optometry school as entry level and perceive the need for additional clinical education. The creation of new residency programs and the expansion of existing ones may occur in a variety of settings. For residency education to realize its full potential, optometry must seek federal support for post-graduate clinical education. This would be consistent with federal support provided to other professions for the support of post-graduate clinical education.

Dichromacy and its effect on a young male.

Deuteranopia is a dichromatic color vision defect which may cause problems for an individual asked to perform color-oriented tasks. This can especially create problems for grade school children in classrooms whose instructional material depends heavily on color. This case report presents a child with a deuteranopic color vision defect who was mistakenly labeled learning disabled because of his inability to learn and perform color oriented tasks.

Evaluation of motivating factors for selecting optometric residency education.

There are now more than 50 accredited optometric residency programs. We sought to learn the primary motivating factors for selecting residency education beyond the traditional 4-year professional program. Questionnaires addressing this issue were sent in May 1990 to directors of all Council on Optometric Education (COE)-accredited residency programs for distribution to currently participating residents. Of the 81 existing residency positions, 61 questionnaires (75 percent) were returned. Three residents (5 percent) accepted positions in residency programs because they had no definite practice plans following graduation. One resident (2 percent) could not take state board examinations and elected to enter a residency program until licensure could be obtained. Fifty-three (85 percent) selected residency education to enhance their clinical skills, and five residents (8 percent) cited other reasons, such as to prepare for a career in optometric education, to enhance long-term career objectives, and to mature. For 50 (83 percent) of the respondents, residency education was their first choice following graduation from optometry school. We conclude that optometric residency education is highly valued as a source of enrichment of clinical skills.

Induced hyperphoria in anisometropic presbyopia.

Anisometropia occurring either as a result of physiological or acquired etiologies may present a challenge to the optometrist if the patient is presbyopic. Fortunately, many patients with anisometropic presbyopia are able to adapt to near induced hyperphoria. There are, however, several options available for the optical management of symptomatic patients with near induced hyperphoria. These include: displacement of the distance optical centers, setting the bifocal segment higher than usual, using a combination of these two, dissimilar bifocal segments, slab-off prism and contact lenses. This paper reviews clinical considerations as well as the available spectacle management options.

Optometric care of patients with age-related cataracts.

As the geriatric population has increased in size, so has the number of patients developing age-related cataracts. This paper discusses a variety of clinical topics as they relate to the diagnosis and management of age-related cataracts. Particular emphasis has been placed on the importance of patient communication in the optometric care of cataract patients.

Accommodative spasm: a study of 17 cases.

Accommodative spasm (AS) is rarely reported in the literature. We studied 17 patients with accommodative spasm. Most patients were clinically emmetropic. Ten patients also manifested a spasm of the near reflex (SNR). The probable etiology of the accommodative disorder for most patients was psychogenic as revealed by case histories and visual field analysis. Treatment consisted primarily of plus reading lenses and, in some instances, orthoptic training. Some patients also underwent psychological counseling. Follow-up ranged from 2 months to 30 months. Although visual symptoms improved for most patients, only four patients had complete resolution of the spasm.

A brief history of optometric residency education.

Residency education in optometry has enjoyed remarkable growth as evidenced by the proliferation of the number of residency programs. This paper briefly reviews the history of residency programs in optometry in the United States.

Norms for hand-held rotary prism vergences.

Norms of clinically useful techniques provide a means to measure and compare patient performance against a large clinical population of asymptomatic subjects. This study establishes mean values for vergence ranges (break and recovery) at 6 m and 40 cm using hand-held rotary prisms. Secondary effects of eye preference (dominance), order of prism presentation, and differences of results between clinicians were evaluated and found to have no statistical significance. This is another example of the trend to establish normal values for functions routinely measured in the optometric examination. Values are now available for the most commonly used vergence testing methods: the binocular rotary prism in the phoropter, the prism bar, and the handheld rotary prism. Testing can now be accomplished with or without a phoropter and comparisons can be made to normal values.