Search PubMed⌕ Search

Biomedical subjects

W B Jackson

Publications and source records attributed to W B Jackson.

At least 37 records · Page 2Linked to original sources

Schnyder's crystalline corneal dystrophy in association with hyperlipoproteinemia: histopathological and ultrastructural findings.

A 61-year-old man with Schnyder's crystalline corneal dystrophy showed a slight reduction in vision during 16 years of observation. Plasma lipoprotein analysis done 10 years after presentation showed type IIA hyperlipoproteinemia, which was also detected in one of four siblings examined, none of whom showed the characteristic corneal dystrophy. Electron microscopic studies on corneal biopsy specimens from the patient showed abundant crystalline material and vacuoles predominantly in the superficial corneal stroma, with occasional keratocytes and rare basal epithelial cells containing laminated structures. The findings of a focal continuity between the trilaminar membrane around some of the stromal vacuoles and the plasmalemma of the keratocytes as well as dissolution of the plasmalemma in other keratocytes are consistent with the hypothesis of a local cellular role in the development of this corneal disorder.

Cornea↗

Towards an artificial cornea: surface modifications of optically clear, oxygen permeable soft contact lens materials by ammonia plasma modification technique for the enhanced attachment and growth of corneal epithelial cells.

The advent of high water content, oxygen permeable contact lens materials has made the intracorneal implants more feasible. A major obstacle encountered is the regrowth of a stable epithelium over the implant. Therefore, ammonia gaseous plasma modification technique was used to modify the surface chemical properties of soft contact lens material such as poly(2-hydroxyethyl methacrylate and methacrylic acid), PHEMA-MAA copolymer, in an attempt to enhance the cell attachment and growth of rabbit corneal epithelial cells.

Ammonia↗

Ocular complications of a topical methylene blue-vasoconstrictor-anesthetic preparation.

We describe six patients who demonstrated a spectrum of adverse ocular reactions following the use of a nonprescription topical medication composed of methylene blue, naphazoline hydrochloride or nitrate, and amylocaine hydrochloride. This preparation has been commonly sold in Quebec and France for various complaints of ocular discomfort and redness. The ocular complications included asymptomatic blue discoloration of the conjunctiva, follicular and papillary conjunctivitis and varying degrees of cicatrization of the conjunctiva and cornea. The most severe reaction, progressive bilateral ocular pseudopemphigoid, occurred in a 73-year-old woman, presumably due to at least one of the ingredients of this medication.

Adult↗

Peripheral corneal ulcer associated with benign hypergammaglobulinemic purpura.

We describe a 56-year-old woman with benign hypergammaglobulinemic purpura in whom scleritis, acute stromal keratitis and peripheral corneal furrowing developed. Initial therapy with topical antibiotics and steroids failed to control the scleritis and keratitis. Subsequent treatment with plasmapheresis led to a decrease in circulating immune complex and serum immunoglobulin levels, with resolution of the ocular inflammation. After 8 years of follow-up the serum IgG and IgM levels were again elevated; however, the corneal disease remained quiescent. Plasmapheresis may have a role in the therapy of this and other immune-complex-mediated ocular diseases.

Corneal Ulcer↗

Preventing transmission of human immunodeficiency virus in ophthalmologic practice.

The risk of acquiring HIV infection during an ophthalmologic examination appears to be small but theoretically present. Since it is not always possible to ascertain the presence of HIV infection and because of the grave consequences of infection, all patients must be considered potential carriers. Appropriate preventive measures are imperative. Fortunately, HIV is easily eradicated from the environment. Routine handwashing and cleansing of equipment are normally sufficient to prevent its spread. The fear of AIDS effectively reminds us to adhere to high standards of infection control. This has the added benefit of protecting both physician and patient from other, less lethal but more infective conditions.

Acquired Immunodeficiency Syndrome↗

Canadian ophthalmologists and low vision: a national survey.

It is estimated that by the year 2000 there will be a 36% increase in the number of people over 65 years of age compared with the number in 1977. Since visual impairment in developed countries is largely age related, the number of people who require low-vision services is rapidly increasing. A questionnaire survey was carried out to assess the extent of provision of low-vision services by ophthalmologists in Canada; 119 physicians (13%) responded. The results show that few ophthalmologists provide low-vision care. This situation warrants immediate attention.

Age Factors↗

Factors affecting the successful use of low-vision aids.

Telephone interviews were conducted with 100 partially sighted patients who had been using low-vision aids for at least 6 months. Only "near-vision" aids were examined. The patients were asked how often they used the aid(s), how satisfied they were with it and whether they had any specific complaints about it. There were no differences in the responses between head-borne and hand-held optical aids. The preferred range of dioptric power was 11 to 20 D.

Audiovisual Aids↗

Laser therapy of conjunctival papillomas.

Carbon dioxide (CO2) laser therapy was successfully used in the treatment of recurrent conjunctival papillomas in a 40-year-old man. Surgical excision, cryotherapy and immunotherapy with transfer factor and dinitrochlorobenzene had all been unsuccessful in eradicating the lesions. CO2 laser therapy should be considered as an alternative treatment for conjunctival papillomas refractory to other forms of therapy.

Adult↗

Intraocular penetration of netilmicin.

The intraocular penetration of the aminoglycoside netilmicin following intramuscular and subconjunctival injection was studied in 102 patients undergoing elective cataract surgery. Those who received either a single 1.5-mg/kg intramuscular injection or two 1.5-mg/kg injections 6 hours apart subsequently had therapeutic serum levels but aqueous levels of less than 2.4 micrograms/mL. Those who received a subconjunctival injection of either 12.5 or 25 mg of netilmicin subsequently had aqueous levels of up to 36 or 85.6 micrograms/mL; therapeutic levels in the anterior chamber persisted for 7 to 9 hours, with higher levels following the 25-mg injection. Despite wide variation in the aqueous levels following subconjunctival injection the ocular penetration of netilmicin was comparable to that reported for other aminoglycosides. No major complications were associated with the use of this antibiotic by either route.

Aqueous Humor↗

Treatment of herpes simplex keratitis: comparison of acyclovir and vidarabine.

At three university centres 66 patients presenting with herpetic dendritic or geographic ulcers participated in a double-blind comparative study of 3% acyclovir and 3% vidarabine ointment. There was healing in 31 (97%) of the 32 patients treated with acyclovir, in a mean time of 6.3 days, and in 30 (88%) of the 34 treated with vidarabine, in a mean time of 7.1 days. The two medications were statistically equally effective, no difference being demonstrated in the healing rate, in the frequency of punctate epithelial keratitis or stromal keratitis, or in the final visual acuity.

Acyclovir↗

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↗

Treatment of blepharitis and blepharoconjunctivitis: comparison of gentamicin-betamethasone, gentamicin alone and placebo.

At two university centres 46 patients presenting with symptomatic infective blepharitis or blepharoconjunctivitis participated in a double-blind study of a new antibiotic-steroid ointment containing gentamicin and betamethasone. There was no significant difference in response to 2 weeks of therapy between the patients treated with this ointment and those treated with either an ointment containing gentamicin alone or a placebo ointment. There was also no significant correlation between the clinical response and the results of the bacterial cultures of swabs obtained at the beginning and the end of the study. However, the patients treated with the placebo had a much higher rate of recurrence of their symptoms over a 6-week follow-up period. The patients who before treatment had associated rosacea, dry eyes and a long duration of symptoms showed a poor response to therapy.

Adolescent↗

Cryotherapy for precancerous melanosis (atypical melanocytic hyperplasia) of the conjunctiva.

Two patients with progressive, diffuse precancerous melanosis (intraepithelial atypical melanocytic hyperplasia or melanocytic dysplasia) of the conjunctiva were treated with cryotherapy. In one patient, the contiguous cutaneous portions of both eyelids were involved and received the same therapy; the extensive disease of the patient was managed by two cryotherapy sessions during a period of 21/2 months. The melanocytic process in both patients showed a good response to this therapy, which resulted in a slough of the superficial conjunctiva with reepithelialization from adjacent areas. Neither patients has shown recurrent disease in more than seven months of follow-up, although one patient had incomplete regression of the melanocytic condition in the perilimbal region, which was subsequently treated by an excisional biopsy. Serious complications occurred in one patient who had corneal and lenticular opacities; this patient had severe extensive disease for which exenteration was considered the only feasible alternative therapy to control the melanocytic proliferation disorder adequately. Less severe complications also developed, including trichiasis, ptosis, transient hypotony, and macular edema. In this article, we discuss the clinical and histologic features of acquired pigmentations of the conjunctiva, the criteria for their management, and the approaches to minimize the complications that we have encountered with cryotherapy.

Aged↗

Pseudomonas aeruginosa scleritis.

In two patients Pseudomonas aeruginosa scleral infection led to ocular perforation. In one patient, a scleral abscess was identified anteriorly. A scleral perforation occurred at a more posterior focus, but the eye was salvaged with minimal residual visual function. In the other patient, perforation at the corneoscleral limbus occurred after initial corneal improvement with antibiotic therapy; histopathologic examination of the enucleated globe disclosed an abscess extending from the corneoscleral limbus to the equator superiorly.

Aged↗