Peter Donshik - Academia.edu (original) (raw)

Papers by Peter Donshik

Immunology and Allergy Clinics of North America, Feb 1, 2008

Contact lens wearers with giant papillary conjunctivitis report a variety of symptoms, including ... more Contact lens wearers with giant papillary conjunctivitis report a variety of symptoms, including decreased lens tolerance, increased lens awareness, excessive lens movement, increased mucus production associated with ocular irritation, redness, burning, and itching. This article reviews the clinical signs and symptoms related to contact lens-induced giant papillary conjunctivitis. The epidemiology, histology, and pathophysiology are reviewed in depth. A variety of treatment strategies are discussed that enable patients with this condition to remain in contact lenses.

American Journal of Ophthalmology, Oct 1, 1983

Oxford University Press eBooks, May 19, 2022

Dry eye is a very common finding and is caused by many conditions. In Sjögren’s, the autoimmune d... more Dry eye is a very common finding and is caused by many conditions. In Sjögren’s, the autoimmune disease causes dry eye. The practitioner should rule out infection, non-immune-related sources, or dryness susceptibilities for infections. Dry eye disease is managed by educating the patient, using ocular lubricants, modifying the local environment (e.g., humidification), lid hygiene, autologous tears, and tear conservation. Additionally, systemic anti-inflammatory approaches are used. While there are now more treatment options, management is an art that should be based on the best scientific evidence available. The stepwise approach discussed in this chapter is an attempt to offer a reasonable approach to the management of dry eye disease rather than a rigid cookbook management tool.

Expert Review of Ophthalmology, Feb 1, 2010

Silicone hydrogel contact lenses were introduced in 1999 after polymer chemists were able to succ... more Silicone hydrogel contact lenses were introduced in 1999 after polymer chemists were able to successfully copolymerize conventional hydrogel material with silicone polymers, creating a soft material with high oxygen permeability. Comfort has been achieved through surface modifications to improve the wettability of these hydrophobic copolymers. Lotrafilcon A was introduced in 2001 and had the highest oxygen permeability of any of the commercially available silicone hydrogel contact lenses. The popularity of silicone hydrogels has steadily increased since their introduction, and they now account for more than 50% of the soft contact lens market in the USA. The popularity of these contact lenses has been fueled by decades of research implicating relative hypoxia, one of the major complications of conventional hydrogel contact lens wear. The overall complication rate for conventional hydrogel contact lenses is low. However, with 38 million contact lens wearers in the USA, even a low complication rate can result in significant morbidity. Most contact lens-related complications are minor and do not cause visual loss. However, serious complications can occur, and this is particularly true for overnight lens wearers. High-Dk silicone hydrogels, including lotrafilcon A, have reduced complications related to hypoxia. Mechanical complications can still occur, but the rate appears to be low and the risk of microbial keratitis appears to be similar to the rate found with overnight wear of conventional hydrogel lenses.

PubMed, Oct 1, 2001

Purpose: The addition of the ocular lubricant hydroxypropyl methylcellulose (HPMC) to a multipurp... more Purpose: The addition of the ocular lubricant hydroxypropyl methylcellulose (HPMC) to a multipurpose contact lens solution conditions the hydrogel lens surface. This investigation reports the clinical benefits to contact lens wearers and the improved physical properties of the solution with HPMC added. Methods: One-hundred forty-seven subjects wearing a variety of hydrogel lenses used a multipurpose solution with and without addition of HPMC and were assessed for product comfort and preference. In the laboratory, conditioning by HPMC was demonstrated in fluid coating, dynamic contact angle, uptake of fluid on hydrogel lenses, and release of HPMC from lenses after soaking. Results: Lens wearers reported the multipurpose solution with HPMC more comfortable, including measures relating to maintaining lens moisture over time. The multipurpose solution with HPMC produced a thicker and longer-lasting layer of fluid on hydrogel lenses and other plastics than other multipurpose solutions. HPMC was found to adsorb to both group 1 and 4 lens materials and release gradually, with detectable amounts releasing from the lens beyond 12 hours. Conclusions: The conditioning properties of the multipurpose solution with HPMC produce improved wetting of lenses and enhanced lens wearing comfort. Binding of HPMC to the lens surface and subsequent time-release is the probable mechanism for these benefits.

Eye & Contact Lens-science and Clinical Practice, Oct 1, 1994

Radiologic Clinics of North America, Feb 1, 1997

PubMed, Oct 1, 1988

Nine ophthalmologists and nine optometrists conducted a premarket study of the Acuvue disposable ... more Nine ophthalmologists and nine optometrists conducted a premarket study of the Acuvue disposable contact lens manufactured by Vistakon, Inc. Of the 812 patients offered the lens, 733 accepted it and were enrolled in the study. These patients were fitted with the lens and followed for a period of 8 months. Over 98% of these patients had 20/25 or better vision on initial fitting; and subjective ratings of lens comfort were very good. Only 3.7% (27 of 733) discontinued wearing their lenses during the study period. Thirty-four patients (5.6%) experienced a problem while wearing their contact lenses.

PubMed, 1991

This study was designed to determine the presence of neutrophil chemotactic factors in the tears ... more This study was designed to determine the presence of neutrophil chemotactic factors in the tears of patients with giant papillary conjunctivitis (BPC) secondary to contact lenses. Chemotactic activity was measured using modified Boyden chambers and the chemoattractant formylmethionyl-leucyl-phenylalanine (f-MLP) for 100 percent response. Elevated levels of chemotactic activity were found in the tears of symptomatic patients (80.8 +/- 6.4, % f-MLP) compared with control tears of asymptomatic contact lens wearers (15.7 +/- 3.3%) and non-contact lens wearers (5.6 +/- 1.2%). Using radioimmunoassay, C5a (serum-derived chemoattractant), leukotriene-B4, and interleukin-1 (immune cell-derived chemoattractants) were not detected in the tears of symptomatic patients. The authors determined whether injured conjunctival cells participate in this process by releasing neutrophil chemotactic factors. Isolated rabbit bulbar conjunctiva incubated with culture medium for 4 and 6 hr released high levels of neutrophil chemotactic factors. The release of these factors from injured conjunctiva support the premise that physical trauma of conjunctival cells induced by contact lenses may be an important component of the pathophysiology of giant papillary conjunctivitis.

Ophthalmology Clinics of North America, Mar 1, 2003

Advances in Therapy, Mar 1, 2000

This multicenter, double-masked, randomized, parallel-group study compared the efficacy and safet... more This multicenter, double-masked, randomized, parallel-group study compared the efficacy and safety of ketorolac tromethamine 0.5% ophthalmic solution with levocabastine 0.05% and ketorolac tromethamine vehicle in patients with seasonal allergic conjunctivitis. One drop of ketorolac, levocabastine, or vehicle was instilled in each eye four times daily for 6 weeks. In the majority of efficacy variables, ketorolac produced the greatest improvements, followed by levocabastine and vehicle. Ketorolac was significantly more effective (P < .05) than vehicle in reducing mean itching scores, palpebral hyperemia, bulbar hyperemia, and edema. Patients treated with ketorolac reported significant improvements (P < .05) in their ability to sleep and to concentrate on work, compared with those who received vehicle. No significant differences were noted among the treatment groups in safety or tolerability. Ketorolac tromethamine 0.5% ophthalmic solution instilled four times daily is effective and safe in reducing the signs and symptoms of seasonal allergic conjunctivitis.

Eye & Contact Lens-science and Clinical Practice, 2003

Springer eBooks, 1997

... Deborah F. Sweeney, 2 Gullapalli N. Rao, 1 and Brien A. Holden2 'Bausch & Lomb Conta... more ... Deborah F. Sweeney, 2 Gullapalli N. Rao, 1 and Brien A. Holden2 'Bausch & Lomb Contact Lens Centre, LV Prasad Eye Institute ... IN DAILY VERSUS TWO-WEEKLY REPLACED CONTACT LENSES Chris O. Imafidon,'Bernice K. Glover, 2 Joe E. Imafidon, 3 Cyprian Asota, 4 ...

Immunology and Allergy Clinics of North America, Feb 1, 1997

Giant papillary conjunctivitis is a syndrome found frequently as a complication of contact lenses... more Giant papillary conjunctivitis is a syndrome found frequently as a complication of contact lenses. Many variables can affect the onset and severity of the presenting signs and symptoms. Rigid gas permeable contact lenses appear to result in less severe signs and symptoms, with a longer time before the development of giant papillary conjunctivitis. Nonionic, low-water-content soft contact lenses tend to produce less severe signs and symptoms than ionic, low-water-content soft contact lenses. Enzymatic treatment appears to lessen the severity of signs and symptoms. The association of an allergy appears to play a role in the onset of the severity of the signs and symptoms but does not appear to affect the final ability of the individual to wear contact lenses. Using multiple treatment options, such as changing the polymer to a glyceryl methyl methacrylate or a rigid lens, or utilizing a soft lens on a frequent-replacement basis, can result in a success rate of over 90%. In individuals who still have a return of symptoms, the use of topical mast cell stabilizers or a nonsteroidal anti-inflammatory drug as an adjunctive therapy offers the added possibility of keeping these patients in contact lenses.

The Journal of Allergy and Clinical Immunology, Sep 1, 1985

Previous studies in our laboratory have demonstrated pollen-specific IgG antibodies in the tears ... more Previous studies in our laboratory have demonstrated pollen-specific IgG antibodies in the tears of patients with vernal conjunctivitis (VC) and elevated tear IgG levels in patients with contact lens-induced giant papillary conjunctivitis (GPC). Tear secretions were examined for complement (C) proteins to determine the role of this effector system in the pathogenesis of these ocular disorders. The tears of VC (15) and GPC (10) patients with active disease had elevated tear levels of both C3 and factor B. By use of transferrin as a marker for the leakage of plasma proteins into the tears, most C3 was locally produced by the conjunctival tissues. Although immune complexes could not be detected in the tear secretions, increased levels of C3 des Arg were present in the tears that suggested complement activation with the generation of anaphylatoxins. These studies suggest that complement may be important in the inflammatory ocular process of VC and GPC and that the generation of anaphylatoxins (C3a), even by nonimmune mechanisms, may contribute to basophil and mast cell activation with the release of inflammatory mediators into the tear secretions.