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Biomedical subjects

Peter K Kaiser

Publications and source records attributed to Peter K Kaiser.

33 records · Page 2Linked to original sources
PubMed2004

Optical coherence tomography 3: Automatic delineation of the outer neural retinal boundary and its influence on retinal thickness measurements.

PURPOSE: To investigate the automatic delineation of the outer limits of the macular neural retina, by using the optical coherence tomography (OCT)-3 built-in software, and to determine its influence in assessing retinal thickness in the normal macula. METHODS: Retrospective analysis of the OCT3 data at a tertiary-care referral center was performed to study the automatic delineation of the outer neural retina boundary generated by the OCT built-in software. In parallel, a cross-sectional study was designed to compare retinal thickness measurements obtained at specific macular regions of nine normal eyes by the automatic measurement tool with those obtained using a manual-caliper-assisted technique. RESULTS: OCT data from 121 eyes were evaluated. Two parallel, linear highly reflective layers (HRL) were visible at the level of the outer retinal boundary in normal macular regions. Disappearance of the inner and maintenance of the outer HRL was noted in the presence of eye conditions affecting the external retinal layers. The automated software delineation for the outer retinal border was primarily guided by the presence of the inner HRL, whereas the correlation of the OCT findings with the expected clinical and angiographic features on eyes presenting specific macular conditions pointed toward a deeper retinal pigment epithelium-retina interface occurring at the level of the outer HRL. There was a statistically significant difference between the retinal thickness in specific normal macular regions obtained by the automatic measurement tool and the caliper-assisted technique in which the outer retinal border delineation was based on the outer HRL (P = 0.008, Wilcoxon signed rank test). CONCLUSIONS: Incorrect delineation of the outer neural retina boundary is occurring with the automated retinal thickness measurement tool of the OCT3 software. At specific regions of the normal macula, retinal thicknesses were significantly underestimated due to such misalignment.

Adolescent↗
PubMed2004

Verteporfin ocular photodynamic therapy.

This article reviews the pharmacotherapeutics of verteporfin (Visudyne), Novartis Pharma AG) used in ocular photodynamic therapy. The chemistry, pharmacokinetics and pharmacodynamics of the drug are reviewed. The article highlights and summarises the results of the multi-centre, randomised, controlled clinical trials with verteporfin to treat subfoveal choroidal neovascularisation in age-related macular degeneration, ocular histoplasmosis syndrome and pathologic myopia. In addition, the safety profile and side effects of verteporfin are discussed.

Choroidal Neovascularization↗
PubMed2003

A novel mutation in the RDS/Peripherin gene causes adult-onset foveomacular dystrophy.

PURPOSE: To describe a novel mutation in the RDS/Peripherin gene that results in a moderately severe form of adult-onset foveomacular dystrophy. DESIGN: Observational case series. METHODS: Selected members of a family with adult-onset foveomacular dystrophy underwent complete ophthalmic evaluation, including fundus photography and fluorescein angiography, in a tertiary care referral center. The study population consisted of 12 members of a Caucasian kindred. After providing informed consent, patients donated blood for genomic DNA extraction and mutational screening using standard techniques. The main outcome measure were the presence of a RDS/Peripherin gene mutation in a patient with the disease and its absence in unaffected family members and controls. RESULTS: Eight affected family members and no unaffected family members demonstrated a single guanine base deletion at nucleotide 112 that led to premature termination at amino acid 38 of RDS/Peripherin polypeptide. This frameshift mutation results in truncation of nearly 90% of the gene product, thus probably representing a null allele. That results in a relatively severe phenotype, with choroidal neovascularization developing in two patients and geographic atrophy involving the macula in three patients. CONCLUSIONS: We describe a frameshift null mutation in the RDS/Peripherin gene associated with a relatively severe manifestation of adult-onset foveomacular dystrophy in affected family members.

Adult↗
PubMed2003

Clinicopathologic study after submacular removal of choroidal neovascular membranes treated with verteporfin ocular photodynamic therapy.

PURPOSE: To report the clinicopathologic findings after submacular removal of choroidal neovascular membranes (CNV) treated with verteporfin ocular photodynamic therapy. DESIGN: Interventional case series. METHODS: Retrospective review of eight eyes of eight patients who underwent submacular surgery for CNV after having previously received verteporfin ocular photodynamic therapy for presumed ocular histoplasmosis (one patient), age-related macular degeneration ([AMD] three patients) pathologic myopia (two patients), punctate inner choroiditis (one patient), and idiopathic CNV (one patient). All cases had undergone ocular photodynamic therapy with verteporfin using standard protocols. Six of eight patients suffered a submacular hemorrhage after ocular photodynamic therapy, and two of eight patients refused further ocular photodynamic therapy. All patients subsequently had submacular surgery with removal of the CNV. One membrane was routinely processed, sectioned, and stained with hematoxylin and eosin. Five membranes were stained with toluidine blue for light microscopic examination. Semithin (1.0 microm) sections were cut and stained with uranyl acetate-lead citrate for transmission electron microscopy. RESULTS: Choroidal neovascular membranes were removed at 3 days (presumed ocular histoplasmosis), 29 days (punctate inner choroiditis), 63 days (AMD, pathologic myopia), 66 days (AMD), 107 days (pathologic myopia), 116 days (AMD), and 152 days (idiopathic) after verteporfin ocular photodynamic therapy. Histopathologic and ultrastructural examination showed areas of vascular occlusion at 3 days that were not seen at later time points. All specimens had patent CNV. There were signs of vascular damage with extravasated erythrocytes and fibrin, pigment clumping in cells, and inflammatory cells in all but the 3-day specimen. CONCLUSIONS: This case series presents data only from patients who refused repeat treatment with ocular photodynamic therapy or who developed submacular hemorrhage after initial photodynamic therapy. Histopathologic evaluation of CNV 3 days after verteporfin ocular photodynamic therapy showed partial vascular occlusion that was not present in later specimens. These later specimens demonstrated evidence of vascular damage. Verteporfin ocular photodynamic therapy does not appear to lead to permanent and complete occlusion of the CNV. Thus, treatments that lead to permanent closure of CNV without damage to the retinal pigment epithelium and sensory retina are still needed.

Adult↗
PubMed2003

Acute endophthalmitis following intravitreal triamcinolone acetonide injection.

PURPOSE: To report the clinical features, causative organisms, management, and visual acuity outcomes of eight eyes of eight patients who developed acute postoperative endophthalmitis following intravitreal injection of triamcinolone acetonide (IVTA). DESIGN: Retrospective, multicenter, interventional, case series. METHODS: A retrospective, interventional, case series of all patients with acute postoperative endophthalmitis following IVTA at seven academic clinical centers between March 2001 and July 2002. RESULTS: A total of 922 IVTAs were performed. Eight eyes of eight patients with acute postoperative endophthalmitis were identified in the 6 weeks following IVTA for an incidence of 0.87% (95% confidence interval of 0.38% to 1.70%). The median time to presentation was 7.5 days (range, 1-15 days) after IVTA. The most common clinical findings were iritis (n = 8), vitritis (n = 8), hypopyon (n = 8), pain (n = 7), red eye (n = 6), and decreased vision (n = 5). The median presenting visual acuity was 20/1127 (range, 20/60 to light perception). Initial treatment consisted of vitreous tap and injection of antibiotics (n = 6) or pars plana vitrectomy and injection of intravitreal antibiotics (n = 2). Intraocular cultures yielded identification in seven patients. One demonstrated intracellular gram-positive cocci in chains with numerous polymorphonuclear cells on gram stain. The median postinfection vision was 20/400 (range, 20/40 to no light perception). Three patients ended up with no light perception visual acuity, including enucleation (n = 1) and phthisis (n = 1). CONCLUSIONS: Acute postoperative endophthalmitis following IVTA occurs rapidly and can result in severe loss of vision.

Acute Disease↗
PubMed2003

Occlusive vasculitis in a patient with concomitant West Nile virus infection.

PURPOSE: To describe a patient with occlusive, retinal vasculitis and concomitant, confirmed, acute West Nile virus (WNV) infection. DESIGN: Observational case report. METHODS: Main outcome measures included comprehensive ophthalmic examination with fluorescein angiography, color photography, and serologic testing for WNV and St. Louis encephalitis (SLE) virus including plaque reduction neutralization testing (PRNT). RESULTS: A 46-year-old woman developed a sudden decrease in vision in her left eye 2 weeks after confirmed WNV infection and demonstrated multiple, small, patchy areas of retinal edema with scattered microaneurysms. Fluorescein angiography showed multiple branch artery occlusions with extensive nonperfusion. Serologic titers for WNV were positive for acute infection. Plaque reduction neutralization testing confirmed WNV infection and excluded St. Louis encephalitis virus infection. Other etiologies of occlusive vasculitis were not present. CONCLUSIONS: Occlusive, retinal vasculitis may occur in the setting of acute WNV infection.

Acute Disease↗
PubMed2003

Actinobacillus actinomycetemcomitans endogenous endophthalmitis: report of two cases and review of the literature.

Endogenous endophthalmitis due to Actinobacillus actinomycetemcomitans is an unusual disease with serious sequelae. Of the 4 cases published in the literature only 1 recovered useful vision after treatment. This study reports on 1 additional patient and expands on the previously described brief ophthalmology case report of another patient with marked visual impairment at presentation and good visual recovery after treatment. Of the 5 patients described, 4 had pre-existing heart abnormalities, 3 had permanent pacemakers and 2 had periodontal disease. Definite endocarditis by Duke criteria was present in 3 patients. Endocarditis should be ruled out in every patient with A. actinomycetemcomitans endophthalmitis, even in the absence of systemic complaints and prior penicillin prophylaxis. Eye specimen cultures should be incubated for 10 d. A thorough dental examination should be done in each patient and any periodontal disease should be promptly treated.

Actinobacillus Infections↗
PubMed2003

Endogenous endophthalmitis: an 18-year review of culture-positive cases at a tertiary care center.

A retrospective chart review of all patients seen at the Cleveland Clinic Foundation with infectious endogenous endophthalmitis between January 1982 and August 2000 revealed 34 affected eyes in 27 patients. During this time, the median incidence of endogenous endophthalmitis was 1.8 cases/year, and 48.1% of patients presented as outpatients. Twenty-six patients presented to an ophthalmologist, and the diagnosis was initially missed in almost half the cases. Eleven patients had an unremarkable physical exam except for eye findings. We found an equal incidence of bacterial and fungal endophthalmitis and a predominance of among the fungal etiologic agents. We did not, however, note a predominance of Gramnegative organisms seen mostly in reports from Asia. The microbiologic diagnosis was based on aqueous and vitreous cultures or positive eye histopathology stains in almost two-thirds of cases. The sensitivity of the Gram stain was poor, but its specificity and positive predictive value were excellent. The vitreous cultures obtained by vitrectomy instruments were more sensitive in making the diagnosis than the vitreous needle biopsy. Aside from blood cultures and eye specimen cultures, half the patients had an additional infectious focus, most frequently a urinary tract infection, whereas infectious endocarditis was seen in a small minority. Twelve patients had visual improvement with treatment with a final visual acuity better than 20/200 in 44% of the eyes. Good visual outcome was associated with visual acuity of 20/200 or better at diagnosis and with the absence of hypopyon.

Adult↗
PubMed2002

Bilateral endogenous endophthalmitis caused by HACEK microorganism.

PURPOSE: To report a case of bilateral endogenous endophthalmitis caused by a HACEK group organism (Actinobacillus actinomycetemcomitans). METHODS: An 85-year-old Caucasian female presented with bilateral light perception visual acuity, anterior chamber cells, hypopyon, posterior synechiae, and no red reflex. RESULTS: The patient underwent bilateral vitrectomy, with topical, intravitreal, and systemic antibiotics. Vitreous cultures revealed gram-negative cocco bacilli consistent with Actinobacillus actinomycetemcomitans. At final follow-up, visual acuity was 20/25 RE and 20/40 LE. CONCLUSIONS: Prompt diagnosis and treatment of HACEK [Hemophilus sp. (parainfluenzae, aphrophilus, paraphrophilus), Actinobacillus actinomycetemcomitans, Cardiobacterium hominis, Eikenella corodens, and Kingella kingae] group bacterial endophthalmitis can yield good results.

Actinobacillus Infections↗
PubMed2002

Chest computerized tomography in the evaluation of uveitis in elderly women.

PURPOSE: To describe the usefulness of chest computerized tomography (CT) in the evaluation of uveitis in elderly women and the clinical characteristics of patients with an abnormal chest CT scan. DESIGN: Prospective noncomparative case series. METHODS: We evaluated 30 elderly women, aged 61-83 years, with chronic iritis, vitritis, or choroiditis and with no definitive cause for their uveitis. All patients underwent a battery of diagnostic laboratory studies and chest CT. RESULTS: The diagnostic examination in most patients included serum angiotensin converting enzyme level, serum lysozyme, rapid plasma reagin level, fluorescent treponemal antibody-absorption test, purified protein derivative skin test, and chest x-rays. Chest CT performed on all patients showed parenchymal, mediastinal, and/or hilar adenopathy in 17 patients (57%). Histopathologic confirmation of sarcoidosis with noncaseating granulomas in the biopsy specimens was obtained in 14 patients: eight by mediastinoscopy, two by bronchoscopy, two by conjunctival biopsy, one by nasal biopsy, and one by vitreous biopsy. CONCLUSIONS: Chest CT can be useful in elderly female patients with chronic uveitis for identifying mediastinal lymphadenopathy and other lesions suggestive of sarcoidosis, as well as to help guide tissue confirmation and to rule out other diagnoses including lymphoma.

Aged↗
PubMed2002

Retinal and choroidal vascular occlusion after posterior sub-tenon triamcinolone injection.

PURPOSE: To report a case of retinal and choroidal vascular occlusion occurring as a complication after posterior sub-Tenon triamcinolone injection for treatment of uveitic cystoid macular edema. DESIGN: Interventional case report. METHODS: Retrospective study. A 32-year-old woman with uveitis and cystoid macular edema underwent a right posterior sub-Tenon injection of triamcinolone (40 mg/ml, 1 ml total) through a superotemporal approach after topical anesthesia. After the procedure, the patient experienced severe eye pain, orbital ecchymosis, and globe proptosis consistent with retrobulbar hemorrhage. RESULTS: Dilated fundus examination of the right eye (OD) demonstrated multiple intraretinal hemorrhages with particulate white emboli occluding the retinal and choroidal vessels. Visual acuity was no light perception. Ocular massage and hypotensive therapy was initiated for an intraocular pressure of 50 mm Hg. Canthotomy and cantholysis were performed. A total of 39 months post-incident, her visual acuity improved to 20/100. CONCLUSION: Posterior sub-Tenon triamcinolone injection can rarely result in retinal and choroidal occlusion. Immediate intervention may preserve limited visual acuity.

Adult↗
PubMedDate not supplied

Macular hole with retinal pigment epithelium hyperplasia simulating neoplasm.

A case in which a retinal pigment epithelium migration through a stage IV macular hole onto the retinal surface simulated a retinal pigment epithelium neoplasm is described. A 69-year-old woman presented with a hyperpigmented membranous retinal surface growth temporal to a stage IV macular hole in the left eye. Clinical examination and optical coherence tomography were performed prior to pars plana vitrectomy with membrane peeling. Histopathologic processing revealed melanosomes and retinal pigment epithelium with no evidence of neoplastic cells. Retinal pigment epithelium migration can occur through a full-thickness macular hole onto the retinal surface, simulating a retinal pigment epithelium neoplasm. It may be a poor prognostic indicator for visual success.

Aged↗
PubMedDate not supplied

Presumed sterile endophthalmitis following intravitreal triamcinolone acetonide injection.

BACKGROUND AND OBJECTIVE: To report acute postoperative, presumed sterile endophthalmitis following intravitreal injection of triamcinolone acetonide (IVTA). PATIENTS AND METHODS: Retrospective, interventional, multicenter study of patients with acute sterile endophthalmitis following IVTA injection. RESULTS: A total of 922 IVTA injections were performed. Eight eyes of 8 patients with presumed sterile endophthalmitis were identified. The incidence of endophthalmitis was 0.87% (95% confidence interval, 0.38% to 1.70%). Median time to presentation was 1.5 days (range, 1 to 7 days). Median presenting visual acuity was 20/563 (range, 20/80 to light perception). Initial treatment included vitreous tap and injection of antibiotics (n = 4), pars plana vitrectomy and injection of intravitreal antibiotics (n = 2), or systemic treatment alone with oral levofloxacin (n = 2). Six of 6 intraocular cultures were sterile. Median follow-up was 5.9 months (range, 4 to 9 months) with a median visual acuity at last follow-up of 20/75 (range, 20/40 to counting fingers). CONCLUSIONS: Acute presumed sterile endophthalmitis following IVTA injection presents early in the postoperative period. Visual outcomes are generally good.

Adult↗