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1.
Cancer Epidemiol Biomarkers Prev ; 31(3): 614-624, 2022 Mar 01.
Article in English | MEDLINE | ID: mdl-34933956

ABSTRACT

BACKGROUND: Sun exposure causes cutaneous squamous (SCC) and basal cell (BCC) carcinomas. Human papillomavirus (HPV) infection might cause SCC. METHODS: We examined associations of ß and γ HPV infection in skin-swab DNA and serum antibodies with skin cancer risk, and modification of the carcinogenic effects of sun exposure by them, in case-control studies of 385 SCC cases, 832 BCC cases, and 1,100 controls nested in an Australian prospective cohort study (enrolled 2006-2009). RESULTS: Presence of ß-1 and ß-3 HPV DNA appeared to increase risks for SCC and BCC by 30% to 40% (P adjusted <0.01). BCC was also associated with genus ß DNA, OR = 1.48; 95% confidence interval (CI), 1.10 to 2.00 (P adjusted <0.01). Associations were strengthened with each additional positive ß HPV DNA type: SCC (OR = 1.07; 95% CI, 1.02-1.12) and BCC (OR = 1.06; 95% CI, 1.03-1.10), Ptrend<0.01. Positivity to genus ß or γ in serology, and genus γ in DNA, was not associated with either cancer. There was little evidence that any ß HPV type was more strongly associated than others with either cancer. A weaker association of sun exposure with SCC and BCC in the presence of ß-3 HPVs than in their absence suggests that ß-3 HPVs modify sun exposure's effect. CONCLUSIONS: Our substantive findings are at the level of genus ß HPV. Like SCC, BCC risk may increase with increasing numbers of ß HPV types on skin. IMPACT: The consistency in our findings that HPV infection may moderate the effects of sun exposure, the main environmental cause of SCC and BCC, merits further investigation.


Subject(s)
Carcinoma, Basal Cell , Carcinoma, Squamous Cell , Papillomavirus Infections , Skin Neoplasms , Australia/epidemiology , Carcinoma, Basal Cell/epidemiology , Carcinoma, Basal Cell/etiology , Carcinoma, Squamous Cell/epidemiology , Carcinoma, Squamous Cell/etiology , Humans , Papillomaviridae/genetics , Prospective Studies , Risk Factors , Skin Neoplasms/epidemiology , Skin Neoplasms/etiology , Sunlight/adverse effects
2.
Cancer Epidemiol Biomarkers Prev ; 29(1): 49-56, 2020 01.
Article in English | MEDLINE | ID: mdl-31597664

ABSTRACT

BACKGROUND: Human papillomavirus (HPV) infection is highly prevalent worldwide and may have a role, with sun exposure, in causing cutaneous squamous cell carcinoma. Little is known about the relationship of UV exposure and seroprevalence of cutaneous HPVs in the general population. METHODS: Using multiplex serology, we estimated the seroprevalence of 23 beta and 7 gamma HPVs and 7 other antigens (mu HPV1, HPV63, nu HPV41, alpha HPV16; polyomaviruses HPyV7 and MCV; p53) in a population-based sample of 1,161 Australian 45 and Up Study participants with valid data from blood specimens collected from 2010 to 2012. We calculated prevalence ratios (PR) for the association of each antigen with residential ambient solar UV and other UV-related variables. RESULTS: Seropositivity for at least one beta or gamma HPV was high at 88% (beta HPVs 74%, gamma HPVs 70%), and less in women than men [e.g., PR beta-2 HPV38 = 0.70; 95% confidence interval (CI), 0.56-0.87; any gamma = 0.90; 95% CI, 0.84-0.97]. A high ambient UV level in the 10 years before study enrollment was associated with elevated seroprevalence for genus beta (PRtertile3vs1 any beta = 1.17; 95% CI, 1.07-1.28), and beta-1 to beta-3 species, but not for gamma HPVs. Other UV-related measures had less or no evidence of an association. CONCLUSIONS: Seroprevalence of cutaneous beta HPVs is higher with higher ambient UV exposure in the past 10 years. IMPACT: The observed association between ambient UV in the past 10 years and cutaneous HPVs supports further study of the possible joint role of solar UV and HPV in causing skin cancer.


Subject(s)
Betapapillomavirus/isolation & purification , Carcinoma, Basal Cell/epidemiology , Carcinoma, Squamous Cell/epidemiology , Skin Neoplasms/epidemiology , Sunlight/adverse effects , Warts/epidemiology , Aged , Aged, 80 and over , Antigens, Viral/blood , Antigens, Viral/immunology , Betapapillomavirus/pathogenicity , Carcinoma, Basal Cell/etiology , Carcinoma, Basal Cell/pathology , Carcinoma, Squamous Cell/etiology , Carcinoma, Squamous Cell/pathology , Case-Control Studies , Female , Humans , Male , Middle Aged , New South Wales/epidemiology , Prevalence , Risk Factors , Seroepidemiologic Studies , Sex Factors , Skin/pathology , Skin/radiation effects , Skin/virology , Skin Neoplasms/etiology , Skin Neoplasms/pathology , Warts/blood , Warts/virology
3.
Photochem Photobiol ; 93(6): 1483-1491, 2017 11.
Article in English | MEDLINE | ID: mdl-28710897

ABSTRACT

Sun exposure is the main cause of squamous (SCC) and basal cell carcinoma (BCC) although pattern and amount differ by cancer type, and sun sensitivity is the major host risk factor. Our study investigated risk factors and residential ambient UV in a population-based sample of Australian 45 and Up Study participants: 916 BCC cases, 433 SCC cases, 1224 controls. Unconditional logistic regression models adjusting for key covariates demonstrated 60% increased BCC risk and two-fold increased SCC risk with sun sensitivity, and three- and four-fold increased risk, respectively, with solar keratoses. BCC but not SCC risk increased with higher early-life residential UV in all participants (odds ratio (OR) = 1.54; 95% CI 1.22-1.96 for intermediate; OR = 1.31; 95% CI 1.03-1.68 for high UV at birthplace) and similarly in Australian-born participants (P-values < 0.05). Risk of SCC but not BCC increased with long-term cumulative sun exposure assessed by self-reported outdoor work (OR 1.74, 95% CI 1.21-2.49). In conclusion, sun sensitivity is important for both cancers, early-life UV but not cumulative UV appears to increase BCC risk, the former an apparently novel finding, and SCC risk appears only to be related to long-term cumulative sun exposure.


Subject(s)
Carcinoma, Basal Cell/etiology , Carcinoma, Squamous Cell/etiology , Skin Neoplasms/etiology , Ultraviolet Rays , Adolescent , Age Factors , Australia , Child , Female , Humans , Male , Melanoma/pathology , New South Wales , Reference Standards , Risk Factors , Solar System , Sunlight/adverse effects , Surveys and Questionnaires , Ultraviolet Rays/adverse effects
4.
Cancer Epidemiol Biomarkers Prev ; 26(8): 1337-1344, 2017 08.
Article in English | MEDLINE | ID: mdl-28483968

ABSTRACT

Background: Serologic testing for antibodies against epitopes from pathogens is a valuable tool for investigating the relationship between infection and disease. This study comprehensively evaluates the impact of preanalytic variation on antibody seropositivities to a selected set of antigens arising from delays in processing of blood samples, preprocessing storage temperature, and vacutainer type.Methods: We assessed peripheral blood collected from 29 volunteers in four different Vacutainer types [ethylenediaminoetetraacetic acid (EDTA), acid-citrate-dextrose (ACD), lithium heparin (LH), serum separator tubes (SST)], and stored at 4°C or room temperature for 0, 1, 2, 3, 4, 5, and 6 days before processing. Multiplex serology was used to determine antibody reactivity against 35 antigens derived from human papillomaviruses, human polyomaviruses, Epstein-Barr virus, and Helicobacter pylori Cohen's κ statistic was used to measure agreement on seropositivity status between samples exposed to standard and nonstandard clinical practice conditions.Results: For samples processed without delay, κ was not associated with storage-temperature (P value range 0.23 to 0.95) or vacutainer type (P value range, 0.35-0.89). Kappa did not significantly decline with increasing delays in processing for any vacutainer-type storage temperature combination (P slope range, 0.06-1.00).Conclusions: Antibodies to epitopes from various pathogenic infectious agents can be measured reliably from samples stored in SST, EDTA, ACD, or LH vacutainers at either room temperature or 4°C for up to 6 days before processing.Impact: Serologic testing is robust to several preanalytic options. These findings are particularly important for epidemiologic studies recruiting participants from remote settings where sample exposure to preanalytic conditions can vary considerably. Cancer Epidemiol Biomarkers Prev; 26(8); 1337-44. ©2017 AACR.


Subject(s)
Antibodies/chemistry , Antigens/chemistry , Blood Specimen Collection/methods , Humans
5.
Dalton Trans ; 44(8): 3686-700, 2015 Feb 28.
Article in English | MEDLINE | ID: mdl-25361228

ABSTRACT

A series of mono- and bi-metallic metal complexes (with Cu(II), Pt(II) and Zn(II)) with substituted polypyridyl ligands have been prepared and their binding affinities towards quadruplex (c-Myc and human telomeric) and duplex DNA (ds26 and calf thymus) determined using fluorescent indicator displacement (FID) assays and UV/vis spectroscopic titrations. These studies have shown that the number of aromatic rings and number/position of cyclic amine substituents on the ligands, play an important role in defining the DNA binding abilities of the resulting metal complexes. We also show that bi-metallic complexes prepared using a novel terpyridine-cyclen ligand have higher affinity towards G-quadruplex DNA as compared to their mono-metallic counterparts. Cytotoxicity assays were carried out for all the new complexes against an osteosarcoma cancer cell line (U2OS) as well as a normal fibroblast cell line (GM05757). Several of these compounds displayed cytotoxicity similar to that of cisplatin.


Subject(s)
Coordination Complexes/chemical synthesis , Copper/chemistry , G-Quadruplexes , Platinum/chemistry , Zinc/chemistry , Apoptosis/drug effects , Cell Line, Tumor , Coordination Complexes/chemistry , Coordination Complexes/toxicity , Crystallography, X-Ray , Cyclams , Cytotoxins/toxicity , Heterocyclic Compounds/chemistry , Humans , Ligands , Molecular Conformation , Pyridines/chemistry
6.
J Chem Biol ; 4(4): 159-65, 2011 Oct.
Article in English | MEDLINE | ID: mdl-22368708

ABSTRACT

UNLABELLED: Inhibition of protein kinases in the fight against disease remains a constant challenge for medicinal chemists, who have screened multitudes of predominantly planar organic scaffolds, natural and synthetic, to identify potent-albeit not always selective-kinase inhibitors. Herein, in an effort to investigate the potential biological utility of metal-based compounds as inhibitors against the cancer-relevant targets mitogen-activated protein kinase and cyclin-dependent kinase 2, we explore various parameters in planar platinum(II) complexes with substituted phenanthroline ligands and aliphatic diamine chelate co-ligands, to identify combinations that yield promising inhibitory activity. The individual ligands' steric requirements as well as their pattern of hydrogen bond donors/acceptors appear to alter inhibitory potency when modulated. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s12154-011-0059-5) contains supplementary material, which is available to authorized users.

7.
Ophthalmology ; 108(9): 1688-94, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11535474

ABSTRACT

OBJECTIVE: To evaluate the safety and efficacy of Intrastromal Corneal Ring Segments (ICRS) for the correction of myopia. DESIGN: Nonrandomized, comparative trial. PARTICIPANTS: Patients enrolled in the United States Food and Drug Administration phase II and phase III clinical trials of the ICRS had best spectacle-corrected visual acuity (BSCVA) of 20/20 or better, myopia of -1.00 to -3.50 diopters (D), and a cylindrical correction of 1.00 D or less as measured by manifest refraction. INTERVENTION: Surgical correction of myopia with an ICRS. MAIN OUTCOME MEASURES: Efficacy was assessed by predictability of refractive outcome (deviation from predicted cycloplegic refraction spherical equivalent), stability of refractive effect, and postoperative uncorrected visual acuity. Safety was assessed by adverse events, maintenance or loss of preoperative BSCVA, and induced manifest refraction cylinder. RESULTS: Four hundred fifty-two patients were enrolled at 11 investigational sites in both studies. Of the 454 surgical attempts, 449 received an ICRS in one eye (0.25, 0.30, and 0.35 mm in 148, 151, and 150 eyes, respectively). First surgeries were attempted in 452 patients. An ICRS was successfully implanted in 447 initial eyes, and 5 surgeries were discontinued. Of the five discontinued surgeries, three patients subsequently exited from the study, and two patients went on to have the ICRS implanted in the second eye, bringing the total number of successful implants to 449 patient eyes. Month 24 postoperative follow-up was completed on 358 patients (80%). At month 24, 328 of 354 eyes (93%) were within +/-1.00 D of predicted refractive outcome. Refraction changed by 1 D or less in 97% of eyes (421/435) between 3 and 6 months after implantation and in 99% (343/348) between months 18 and 24. Before surgery, 87% of eyes (390/448) saw worse than 20/40 uncorrected; 24 months after surgery, 55% of eyes (196/358) saw 20/16 or better, 76% (271/358) saw 20/20 or better, and 97% (346/358) saw 20/40 or better. Although two eyes (2/358; 0.5%) lost two or more lines of BSCVA at 24 months; visual acuity in both was 20/20 or better. Intraoperative complications included anterior corneal surface perforation (three eyes) and anterior chamber perforations (two eyes, one during an attempted exchange procedure); all healed spontaneously without suturing and without loss of BSCVA. The ICRS was repositioned in five eyes to increase correction. Postoperative complications in one eye each were infectious keratitis, shallow segment placement, and loss of two lines of BSCVA at two or more consecutive examinations (subsequently regained). CONCLUSIONS: The ICRS safely, predictably, and effectively reduced or eliminated myopia of -1.00 to -3.50 D. The refractive effect was stable over time.


Subject(s)
Corneal Stroma/surgery , Myopia/surgery , Prostheses and Implants , Prosthesis Implantation , Adult , Aged , Corneal Stroma/physiopathology , Female , Follow-Up Studies , Humans , Male , Middle Aged , Myopia/physiopathology , Ophthalmologic Surgical Procedures , Polymethyl Methacrylate , Postoperative Complications , Prostheses and Implants/adverse effects , Refraction, Ocular , Treatment Outcome , Visual Acuity
8.
J Refract Surg ; 17(1): 25-31, 2001.
Article in English | MEDLINE | ID: mdl-11201774

ABSTRACT

PURPOSE: To evaluate the reversibility of refractive effect following removal of the ICRS (intrastromal corneal ring segments; Intacs). METHODS: Data from 34 eyes from which ICRS were removed during United States FDA Phase II and III clinical trials were evaluated with regard to segment size, loss or change of best spectacle-corrected visual acuity (BSCVA), any change of uncorrected visual acuity (UCVA), manifest spherical equivalent refraction, manifest cylinder refraction, stability of manifest cylinder refraction, and subjective visual symptoms. RESULTS: Out of 725 initial or contralateral eyes placed with the ICRS during Phase II and III clinical trials, segments were removed from 34 eyes (4.7%). Other than one (1/725, 0.1%) safety related ICRS removal, 30/725 (4.1%) were due to visual symptoms. ICRS removal was accomplished under topical anesthesia without complications in all eyes. The mean length of time the segments remained in the cornea after initial surgery was 10.3 +/- 5.4 months. At 3 months after ICRS removal, 21 eyes had monitored data available and were within +/-1 line or 10 letters of their preoperative BSCVA. Twenty eyes (20/21, 95%) returned to within +/-1.00 D of their preoperative manifest spherical equivalent refraction. All eyes had a stable refraction at the 3-month examination after removal, and a manifest spherical equivalent refraction within +/-1.00 D of their 1-month examination after removal. Nineteen eyes (19/21, 90%) returned to within +/-2 lines and 16 eyes (16/21, 76%) returned to within +/-1 line of preoperative UCVA. CONCLUSION: The ICRS (Intacs) was easily and safely removed, and eyes returned to preoperative refractive status within 3 months.


Subject(s)
Corneal Stroma/physiopathology , Device Removal , Myopia/physiopathology , Prosthesis Implantation , Visual Acuity/physiology , Corneal Stroma/surgery , Female , Humans , Male , Myopia/surgery , Polymethyl Methacrylate , Postoperative Complications , Prostheses and Implants , Refraction, Ocular/physiology , Safety
9.
J Cataract Refract Surg ; 23(4): 502-8, 1997 May.
Article in English | MEDLINE | ID: mdl-9209984

ABSTRACT

PURPOSE: To evaluate the effectiveness of two-incision radial keratotomy (RK) in correcting low-magnitude refractive myopic astigmatism. SETTING: Two clinical study sites, one in St. Louis, Missouri, USA, the other in Caracas, Venezuela. METHODS: Fifty-seven eyes of 43 patients with low-magnitude myopic astigmatism had two-incision RK at one of two clinical study sites. In the initial phase of this series, 10 eyes with amblyopia at the 20/30 level had surgery at one center. Refractive keratotomy was performed with the radial incision placed in the plus cylinder axis of refraction. This axis was verified as the meridian of greatest corneal curvature by standard keratometry and computer-assisted corneal topographic analysis. Two eyes received a second operation (enhancement). RESULTS: Mean follow-up was 11.1 months (range 6 to 12 months). Mean preoperative and postoperative myopic spherical equivalent measured -1.42 diopters (D) +/- 0.51 (SD) and -0.14 +/- 0.39 D, respectively; the mean reduction was 1.28 +/- 0.59 D (P = .0001). Mean preoperative and postoperative refractive astigmatism was 1.41 +/- 0.45 D and 0.48 +/- 0.33 D, respectively (P = .0001). Mean preoperative and postoperative keratometric astigmatism was 1.26 +/- 0.54 D and 0.31 +/- 0.35 D, respectively, a mean reduction of 0.95 D (P = .0001). The surgical meridian was flattened by an average of 2.06 D by keratometry and the orthogonal meridian, by an average of 1.10 D. Preoperative uncorrected visual acuity (UCVA) was 20/40 or better in five (9%) eyes (range counting fingers to 20/40). Postoperative UCVA acuity was 20/40 or better in all eyes (mean acuity 20/25). In the nonamblyopic subgroup mean postoperative UCVA was 20/24. CONCLUSIONS: A limited number of radial incisions placed in the topographically confirmed axis of greatest curvature are effective in the treatment of low-magnitude myopic astigmatism.


Subject(s)
Astigmatism/etiology , Astigmatism/surgery , Keratotomy, Radial/methods , Myopia/complications , Myopia/surgery , Adolescent , Adult , Aged , Astigmatism/physiopathology , Female , Humans , Male , Middle Aged , Myopia/physiopathology , Retrospective Studies , Treatment Outcome , Visual Acuity
10.
J Refract Surg ; 13(2): 167-70, 1997.
Article in English | MEDLINE | ID: mdl-9109074

ABSTRACT

PURPOSE: To investigate the organization of collagen fibrils in the lyophilized cornea. METHODS: Freshly harvested porcine corneas (n = 10) were lyophilized and examined by synchrotron x-ray diffraction and transmission electron microscopy. RESULTS: Collagen fibrils are highly compacted in lyophilized corneas. They become more widely spaced when the tissue is rehydrated, however, the distribution of imbibed water throughout the stroma is not necessarily homogeneous within an individual cornea, nor is it always similar in specimens that have been rehydrated to similar levels. In lyophilized corneas, the mean center-to-center interfibrilar spacing of the regularly arranged collagen reaches levels found in freshly thawed porcine corneas (between 74% and 78% water by weight) when between 74.3% and 81.6% of the rehydrated lyophilized cornea's weight is water. CONCLUSION: Regularly arranged collagen fibrils are able to reapproximate their original spacings if lyophilized corneal tissue is rehydrated, although the manner in which imbibed water is distributed is somewhat unpredictable.


Subject(s)
Collagen/analysis , Cornea/chemistry , Desiccation , Animals , Body Water , Collagen/ultrastructure , Cornea/ultrastructure , Corneal Stroma/chemistry , Corneal Stroma/ultrastructure , Microscopy, Electron , Swine , X-Ray Diffraction
11.
Eye (Lond) ; 11 ( Pt 1): 57-67, 1997.
Article in English | MEDLINE | ID: mdl-9246278

ABSTRACT

We investigated an individual macular corneal dystrophy (MCD) type II cornea from a 42-year-old woman with markedly reduced antigenic keratan sulphate levels. A characteristic 4.6 A X-ray reflection was evident, and the mid-stroma contained 30% less sulphur than normal. Close packing of collagen was restricted to the superficial stroma. Abnormally large proteoglycan filaments were noted throughout the extracellular matrix and Descemet's membrane's posterior non-banded zone, but not its anterior banded zone. Small, collagen-associated stromal proteoglycans were susceptible to digestion with chondroitinase ABC, but not keratanase I or N-glycanase. On occasion, collagen fibrils ranged in size from 20 nm to 58 nm, with preferential diameters of 34 nm and 42 nm. Corneal guttae were evident, as were numerous endothelial inclusions, most probably due to intracellular fibrillogranular vacuoles similar to those found in the stroma. The endothelium expressed reduced anti-keratan sulphate labelling.


Subject(s)
Cornea/metabolism , Corneal Dystrophies, Hereditary/metabolism , Keratan Sulfate/metabolism , Adult , Collagen/metabolism , Cornea/ultrastructure , Corneal Dystrophies, Hereditary/pathology , Descemet Membrane/metabolism , Descemet Membrane/ultrastructure , Endothelium, Corneal/metabolism , Endothelium, Corneal/ultrastructure , Female , Humans , Microscopy, Electron, Scanning , X-Ray Diffraction
12.
Intensive Crit Care Nurs ; 12(6): 354-8, 1996 Dec.
Article in English | MEDLINE | ID: mdl-9035629

ABSTRACT

Communication with intensive care patients is of paramount importance, especially when communicating with a critically ill patient who is sedated and ventilated, and therefore unable to speak. Disclosure under these circumstances is extremely difficult, so in this situation touch is a valuable means of conveying messages. Consequently, touch as a way of communicating is discussed in this paper, highlighting the advantages and disadvantages. Barriers to communication in this environment are also discussed.


Subject(s)
Communication Barriers , Conscious Sedation/nursing , Critical Care , Nurse-Patient Relations , Respiration, Artificial/nursing , Touch , Humans
13.
Intensive Crit Care Nurs ; 12(2): 71-8, 1996 Apr.
Article in English | MEDLINE | ID: mdl-8845627

ABSTRACT

The purpose in this paper is to consider the importance of early nutrition for critically ill patients, briefly reviewing the effects of malnutrition, and the metabolic response to starvation and sepsis. Discussion includes assessment of nutritional status and nutritional requirements, with a suggested enteral feeding regime; and also the combined effect of enteral nutrition and glutamine on gut integrity and its relevance to nosocomial pneumonia, and the ability of the gut to accept food during critical illness.


Subject(s)
Critical Care , Enteral Nutrition/methods , Protein-Energy Malnutrition/therapy , Critical Illness , Humans , Nutrition Assessment , Protein-Energy Malnutrition/metabolism , Sepsis/metabolism
14.
Ophthalmology ; 102(12): 1908-16; discussion 1916-7, 1995 Dec.
Article in English | MEDLINE | ID: mdl-9098295

ABSTRACT

PURPOSE: A prospective, multicenter, clinical study to evaluate a standardized surgical (Genesis) protocol which includes combined-technique radial incisions in patients seeking reduction of their physiologic myopia. The combined incisions were designed to incorporate the safety of the centrifugal incision technique with the efficacy of the centripetal incision technique. METHODS: A total of 375 eyes undergoing radial keratotomy procedures performed in six different clinical centers were analyzed. All procedures were performed in accordance with the Genesis nomograms. The Genesis protocol called for using preoperative screening pachymetry to guide central clear zone size selection, incising the thinnest corneal quadrant first, suturing corneal perforations, and discouraged more than one enhancement procedure, when indicated. Globe fixation technique served as a study variable. RESULTS: Mean follow-up was 6.2 months (range, 1.5-12 months). Mean residual cycloplegic refraction was -0.48 +/- 0.61 diopters (D) (range, -2.50 to +1.50 D); 92% of eyes were within 1 D of the planned goal of -0.50 D and 85% were within 1 D of emmetropia; 14% were myopic; and 1% was hyperopic by more than 1 D. Uncorrected visual acuity was 20/40 or better in 95% of eyes; the remaining 5% retaining myopic refractive errors. A single procedure was performed in 73% of eyes, and 99% received less than two enhancements. Of eyes with no enhancements, 97% had uncorrected visual acuity of 20/40 or better. One study eye (0.3%) had a two-line loss of spectacle visual acuity. There were no invasions of the central clear zone. Globe fixation was a significant predictor for enhancement incidence (P < 0.001) but not for perforation incidence (P = 0.06). Incision sequence was predictive for perforation incidence (P < 0.0002). CONCLUSION: The combined-technique of radial keratotomy, coupled with the Genesis surgical protocol, affords centrifugal incision safety with centripetal incision efficacy. The Genesis nomograms, with a built in refractive outcome goal of -0.50 D provide an acceptable degree of accuracy and predictability while guarding against hyperopic overcorrection.


Subject(s)
Cornea/surgery , Keratotomy, Radial/methods , Myopia/surgery , Adult , Cornea/physiopathology , Female , Follow-Up Studies , Humans , Male , Middle Aged , Myopia/physiopathology , Postoperative Care , Prospective Studies , Refraction, Ocular/physiology , Treatment Outcome , Visual Acuity/physiology
16.
Arch Ophthalmol ; 111(2): 259-62, 1993 Feb.
Article in English | MEDLINE | ID: mdl-8431166

ABSTRACT

Newly devised software was used to compare the ability of the Topographic Modeling System-1 (Computed Anatomy, New York, NY) and the Corneal Analysis System (EyeSys Laboratories, Houston, Tex) to reproduce power measurements on spherical surfaces. Reproducibility results were compared for spheres of 40.00, 42.50, and 44.00 diopters. The program determines the absolute difference in corneal power at defined keratoscope positions for paired examinations of the same eye. Four examinations of each sphere were obtained with each instrument. Individual points were sampled at specific keratoscope locations at 30 degrees-semimeridional intervals. The program compared variability of measurements at four defined ranges of distance from the vertex normal: within 0.60 mm, 0.61 to 1.5 mm, 1.51 to 2.5 mm, and 2.5 mm or greater. The Corneal Analysis System showed significantly greater variability of readings obtained within 0.60 mm of the vertex normal for all three spheres (P = .001 by Duncan's multiple comparison procedure), whereas the Topographic Modeling System-1 showed equally consistent readings within 0.60 mm as it did between 0.61 and 1.5 mm from the vertex normal.


Subject(s)
Computer Simulation , Cornea/anatomy & histology , Models, Anatomic , Corneal Diseases/diagnosis , Corneal Diseases/epidemiology , Corneal Diseases/pathology , Evaluation Studies as Topic , Humans , Refraction, Ocular , Reproducibility of Results , Software
17.
Cornea ; 11(1): 28-35, 1992 Jan.
Article in English | MEDLINE | ID: mdl-1559344

ABSTRACT

Two computer-assisted topographic analysis systems were evaluated with calibrated spherical surfaces and normal human corneas. The Topographic Modeling System-1 (TMS-1) was found to be statistically more accurate in determining the power of calibrated spheres near the apex and at 1 mm from the apex than the Corneal Analysis System (CAS). The CAS, however, was statistically more accurate at 3 mm from the apex with each calibrated sphere. The small differences in accuracy between the two instruments, however, are unlikely to be of clinical significance. The topographic patterns on color-coded maps from 22 normal corneas of 11 subjects were similar with the two instruments. Simulated keratometry values with the CAS more accurately identified the keratometer-determined major cylinder axis compared with the TMS-1. Conversely, the TMS-1 was more accurate than the CAS at determining the level of corneal astigmatism.


Subject(s)
Astigmatism/diagnosis , Cornea/anatomy & histology , Image Processing, Computer-Assisted , Cornea/pathology , Humans , Models, Anatomic , Ophthalmology/instrumentation , Ophthalmology/methods , Reproducibility of Results
18.
Invest Ophthalmol Vis Sci ; 28(3): 555-9, 1987 Mar.
Article in English | MEDLINE | ID: mdl-3549612

ABSTRACT

The antigenicity of intrastromal and epikeratophakia xenografts of lyophilized corneal tissue was evaluated in nonimmune and immune recipients. Lyophilized feline lenticules were implanted into intrastromal pockets in unsensitized rabbits and rabbits sensitized to the donor cat. In both cases, the grafts remained clear. Sensitized rabbits with clear intrastromal grafts received fresh tissue penetrating keratoplasty grafts from the same donor cat, placed adjacent to the intrastromal grafts. The fresh tissue penetrating keratoplasty grafts were rapidly rejected, while the lyophilized intrastromal grafts remained clear. Cats sensitized to rabbits received lyophilized and rehydrated epikeratophakia grafts shaped from rabbit cornea; these lyophilized grafts also remained clear for the 3-month period of the study. The results indicate that lyophilized and rehydrated corneal stroma, which is devoid of living cells, is not antigenic and is not subjected to immunologic attack, even in cases where the donor and host are of different species and the host has been previously immunized to the donor.


Subject(s)
Cornea/surgery , Corneal Stroma/surgery , Corneal Transplantation , Transplantation, Heterologous , Animals , Cats , Cornea/pathology , Female , Freeze Drying , Immunity , Male , Rabbits
19.
Surv Ophthalmol ; 31(1): 1-36, 1986.
Article in English | MEDLINE | ID: mdl-3529467

ABSTRACT

The peripheral cornea is anatomically and physiologically distinct from its central counterpart. The major differences relate to the gradual transition of corneal tissues to those of the conjunctiva, episclera, and sclera; furthermore, the vascular structures, lymphatics, and inflammatory cells from these neighboring structures are intimately associated with the limbus and periphery of the cornea. The peripheral cornea is thereby predisposed to three main classes of disorders which do not normally involve the central cornea. First, local conditions affecting the sclera and conjunctiva may secondarily spread to involve the limbus and peripheral cornea. These include several infectious diseases, as well as hypersensitivity conditions, mass lesions, and degenerations. Second, due to the associated blood vessels and lymphatics, the peripheral cornea may be involved in a variety of systemic diseases, including vasculitides, autoimmune disorders, and abnormal metabolic conditions. Finally, there are several conditions, such as the noninflammatory peripheral degenerations, which primarily affect the peripheral cornea without associated ocular or systemic changes. In this review, we present a classification and discussion of the various disorders which may involve the peripheral cornea.


Subject(s)
Corneal Diseases/pathology , Aging , Collagen Diseases/complications , Cornea/anatomy & histology , Corneal Diseases/diagnosis , Corneal Diseases/etiology , Eye Injuries/complications , Eye Neoplasms/complications , Humans , Hypersensitivity/complications , Infections/complications , Keratoconjunctivitis/complications , Medical Records , Metabolic Diseases/complications , Physical Examination , Rheumatic Diseases/complications , Skin Diseases/complications , Vascular Diseases/complications
20.
Ophthalmology ; 93(4): 423-32, 1986 Apr.
Article in English | MEDLINE | ID: mdl-3517741

ABSTRACT

Epikeratophakia alters the anterior curvature of the cornea by the addition of a machine-carved donor lenticule. Since March 1980, 88 patients under eight years of age have had epikeratophakia, with at least six months of follow-up. Eighty percent of the original surgeries were successful; some failed grafts were replaced successfully, so that in all, 89% of the patients had successful grafts. The average increase in curvature of the cornea was 14.7 diopters, and the average spectacle overcorrection was +0.56 diopters. In these growing eyes, we documented a myopic shift of 1.5 diopters per year. Visual acuity results varied with the timing of refractive surgery, density of the amblyopia, and the parents' ability to maintain the patching schedule. The largest group of children were those who had unilateral traumatic cataracts. In this group, 7 of 15 patients who had surgery under 4 years of age had final verbal acuities of 20/40 or better. Long-term follow-up has demonstrated that epikeratophakia safely and successfully corrects refractive errors in aphakic children either as a primary procedure, or as a secondary procedure after cataract extraction.


Subject(s)
Corneal Transplantation , Cataract/congenital , Cataract Extraction , Child , Child, Preschool , Evaluation Studies as Topic , Follow-Up Studies , Humans , Infant , Postoperative Complications , Refraction, Ocular , Refractive Errors/physiopathology , Refractive Surgical Procedures , Reoperation , Surgical Wound Infection , Visual Acuity
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