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1.
Australas Phys Eng Sci Med ; 29(2): 203-5, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16845926

ABSTRACT

We have a developed a novel and practical method of imaging the cornea under ultraviolet (UV) light using a digital medium. Wavelengths of 336-371 nm were used to illuminate the cornea. Images were recorded using a UV Nikkor lens and a digital charged coupled device (CCD). Images obtained showed ferritin lines not visible under white light. This study concluded that 336-371 nm is comparable to shorter wavelengths for the imaging of ferritin in the cornea and that a digital image capture system was comparable to that of film.


Subject(s)
Cornea/anatomy & histology , Image Enhancement/instrumentation , Ophthalmoscopes , Ophthalmoscopy/methods , Photography/instrumentation , Signal Processing, Computer-Assisted/instrumentation , Ultraviolet Rays , Equipment Design , Equipment Failure Analysis , Humans , Image Enhancement/methods , Reproducibility of Results , Sensitivity and Specificity
2.
Br J Ophthalmol ; 90(5): 586-92, 2006 May.
Article in English | MEDLINE | ID: mdl-16622088

ABSTRACT

BACKGROUND: Despite the importance of optical quality of an intraocular lens (IOL) on visual outcomes following cataract surgery, objective data on their optical quality are not readily available, and manufacturing standards are industry regulated. The star test is a classic test of optical quality based on examination of the Airy disc and expanded diffraction rings of a point source of light, used mainly for telescope and microscope objectives. METHODS: A physical model eye cell allowed star testing of IOLs under conditions similar to the optical environment in which they operate. 18 IOLs were tested and results compared to actual images produced by these lenses in the model eye cell. Quantitative measures of star testing performance were developed. RESULTS: The optical performance of the IOLs varied, some performing very poorly. Most lenses (13/17) performed better in reverse orientation, while aberrations induced by the haptics of foldable IOLs were also detected. There was excellent correlation between actual images formed and star testing parameters. CONCLUSION: Star testing IOLs was a novel biomedical application of a centuries old, inexpensive method. A concerning variation of optical quality was found, suggesting IOL optical performance data should be more readily available. Independent, authority mandated IOL optical quality standards should be developed, and results readily available to ophthalmologists.


Subject(s)
Lenses, Intraocular/standards , Materials Testing , Optics and Photonics , Acrylic Resins , Contrast Sensitivity , Humans , Models, Anatomic , Ophthalmology/methods , Optometry/standards , Photography , Polymethyl Methacrylate , Prosthesis Design , Refraction, Ocular , Refractometry , Silicones , Visual Acuity
3.
Australas Phys Eng Sci Med ; 27(1): 22-4, 2004 Mar.
Article in English | MEDLINE | ID: mdl-15156704

ABSTRACT

The living human cornea was photographed in ultraviolet light of bandpass 315-326 nm produced by a xenon arc light source and multilayer interference filters. The image was captured on black and white film using a quartz fluorite lens. The photographs revealed structural details not seen in visible wavelengths.


Subject(s)
Cornea/cytology , Microscopy, Ultraviolet/instrumentation , Ophthalmoscopes , Photography/instrumentation , Adult , Equipment Design , Equipment Failure Analysis , Humans , Male , Microscopy, Ultraviolet/methods , Photography/methods , Reproducibility of Results , Sensitivity and Specificity
4.
Br J Ophthalmol ; 88(1): 32-5, 2004 Jan.
Article in English | MEDLINE | ID: mdl-14693768

ABSTRACT

BACKGROUND/AIMS: To describe the long term results of cases of cataract extraction combined with either Molteno implant insertion or trabeculectomy for primary open angle glaucoma. METHODS: This prospective case series followed cases which had cataract extraction and Molteno implant insertion (45 eyes) or trabeculectomy (94 eyes) followed up for a mean of 5.3 years and 3.9 years respectively. RESULTS: Cataract extraction and Molteno implant insertion or trabeculectomy controlled the intraocular pressure at 21 mmHg or less with a probability of 1.00 (95% CI 0.93 to 1.00) at 10 years or more after operation and 0.94 (95% CI 0.89 to 0.99) and 0.73 (95% CI 0.46 to 0.99) at five and 10 years after operation respectively. CONCLUSIONS: Cataract extraction combined with insertion of Molteno implants or trabeculectomy controlled the intraocular pressure in 100% (45/45) and 94% (88/94) of cases respectively.


Subject(s)
Cataract Extraction/methods , Glaucoma, Open-Angle/surgery , Molteno Implants , Trabeculectomy/methods , Aged , Aged, 80 and over , Cataract/complications , Female , Follow-Up Studies , Glaucoma, Open-Angle/complications , Humans , Intraocular Pressure , Intraoperative Complications , Male , Middle Aged , Postoperative Complications/surgery , Prospective Studies , Reoperation , Treatment Outcome , Visual Acuity , Visual Fields
5.
Br J Ophthalmol ; 86(12): 1352-4, 2002 Dec.
Article in English | MEDLINE | ID: mdl-12446362

ABSTRACT

AIMS: To determine the long term outcome of systemic anti-inflammatory fibrosis suppression in cases of threatened trabeculectomy bleb failure in open angle glaucoma. METHODS: This prospective non-comparative case series followed 77 eyes of 63 patients which showed signs of threatened early bleb failure and were treated with oral anti-inflammatory fibrosis suppression of prednisone, a non-steroidal anti-inflammatory agent, and colchicine taken for a mean period of 6 weeks, in addition to standard postoperative topical treatment, for a mean follow up of 6 years. RESULTS: Trabeculectomy with anti-inflammatory fibrosis suppression controlled the IOP at < or =21 mm Hg with a probability of 0.91 (95% CI: 0.81 to 1.0) at 8 years and 0.89 (95% CI: 0.56 to 1.1) at 12 years. There were no reported cases of endophthalmitis, hypotonous maculopathy, late bleb leak, or serious systemic side effects. CONCLUSION: Anti-inflammatory fibrosis suppression provided good control of bleb fibrosis without risk of sight threatening complications in a patient group at high risk of bleb failure.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Glaucoma, Open-Angle/therapy , Intraocular Pressure/physiology , Piroxicam/analogs & derivatives , Trabecular Meshwork/pathology , Trabeculectomy/methods , Vision Disorders/chemically induced , Adult , Aged , Aged, 80 and over , Anti-Inflammatory Agents, Non-Steroidal/adverse effects , Colchicine/adverse effects , Colchicine/therapeutic use , Diclofenac/adverse effects , Diclofenac/therapeutic use , Drug Therapy, Combination , Female , Fibrosis/prevention & control , Flufenamic Acid/therapeutic use , Glaucoma, Open-Angle/drug therapy , Glaucoma, Open-Angle/physiopathology , Humans , Male , Middle Aged , Piroxicam/adverse effects , Piroxicam/therapeutic use , Prednisone/adverse effects , Prednisone/therapeutic use , Prospective Studies , Treatment Outcome
6.
Br J Ophthalmol ; 86(11): 1287-92, 2002 Nov.
Article in English | MEDLINE | ID: mdl-12386091

ABSTRACT

AIMS: To document the long term experience of bone derived hydroxyapatite orbital implants and compare results using scleral wrapped implants with those not using sclera. METHODS: This retrospective case series reviewed the long term follow up of 118 patients with 120 eyes which had undergone enucleation and bone derived hydroxyapatite orbital implant insertion at Dunedin Hospital from 1977 until 2000. Patient details were obtained from theatre records, case note review, patient interview and examination, interview of patient relatives, and family general practitioner records. RESULTS: Of the 120 eyes 84 had bone derived hydroxyapatite orbital implants with sclera and 36 without sclera. Follow up was 0.5-25 years (mean 8.9 years). 25 (19.3%) suffered minor complications of limited exposure of the implant which resolved spontaneously, with implant drilling or wound resuture. Nine (7.5%) suffered major complications requiring explantation. Major complications were more likely in cases with major tissue disruption, ischaemia, or inflammation. There were significantly fewer complications in the group where a bone derived hydroxyapatite orbital implant was implanted without a scleral covering (p<0.05). CONCLUSIONS: The placement of a bone derived hydroxyapatite orbital implant in the socket was associated with a low rate of long term complications and good cosmesis in most cases. The omission of a scleral covering over the hydroxyapatite sphere had some advantages and may prove to be the procedure of choice.


Subject(s)
Durapatite , Eye Enucleation/methods , Orbital Implants , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Eye/pathology , Female , Follow-Up Studies , Humans , Infant , Male , Middle Aged , Patient Satisfaction , Photography , Postoperative Complications/etiology , Retrospective Studies , Sclera/pathology , Time Factors , Tomography, X-Ray Computed
7.
Ophthalmology ; 108(12): 2193-200, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11733258

ABSTRACT

OBJECTIVE: This study was undertaken to provide data on the long-term results of cases of primary open-angle glaucoma with additional risk factors drained by Molteno implants in the province of Otago, New Zealand. DESIGN: Prospective, noncomparative case series PARTICIPANTS: One hundred thirty eyes of 103 patients drained by Molteno implants as the first surgery between 1984 and 1999. INTERVENTION: Insertion of Molteno implant (Ethicon Inc., Johnson & Johnson, Somerville, NJ) using the Vicryl-tie technique. MAIN OUTCOME MEASURES: Intraocular pressure (IOP), visual acuity, visual field. RESULTS: Insertion of a Molteno implant controlled the IOP at 21 mmHg or less with a probability of 1.0 (95% confidence interval [CI], 0.90, 1.0) at up to 7 or more years after surgery. The mean preoperative visual acuity of 20/160 improved to 20/50 after operation and then declined to 20/55 at 5 years and 20/80 after 10 years. The probability of retaining useful vision (visual acuity, >20/400; visual field, >5 degrees radius) was 0.86 (95% CI, 0.77, 0.94) and 0.78 (95% CI, 0.67, 0.89) at 5 and 7 or more years, respectively, after surgery. CONCLUSIONS: The insertion of Molteno implants using the Vicryl-tie technique in this series of 130 cases of primary open-angle glaucoma with additional risk factors controlled the IOP in all cases.


Subject(s)
Glaucoma, Open-Angle/surgery , Molteno Implants , Aged , Aged, 80 and over , Cataract Extraction , Female , Follow-Up Studies , Glaucoma, Open-Angle/physiopathology , Humans , Intraocular Pressure/physiology , Intraoperative Complications , Male , Middle Aged , New Zealand , Postoperative Complications , Prospective Studies , Prosthesis Implantation/methods , Risk Factors , Suture Techniques , Trabeculectomy , Treatment Outcome , Visual Acuity/physiology , Visual Fields/physiology
8.
Ophthalmology ; 108(10): 1796-800, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11581051

ABSTRACT

PURPOSE: To determine the long-term outcomes of patients with traumatic glaucoma treated with Molteno implants at Dunedin Hospital, New Zealand. DESIGN: Prospective, noncomparative, interventional case series. PARTICIPANTS: Thirty-eight patients with traumatic glaucoma and with a mean follow-up of 10.9 years. INTERVENTION: Insertion of Molteno implant. MAIN OUTCOME MEASURES: Intraocular pressure (IOP) and intraocular pressure-related surgical interventions after Molteno implant insertion. RESULTS: Insertion of a Molteno implant controlled the IOP at 21 mmHg or less (with or without hypotensive medication) with a probability of 0.80 (95% confidence interval [CI], 0.66, 0.93) at 5 years and 0.72 (95% CI, 0.56, 0.88) at 10 years. At final follow-up, intraocular pressure was controlled solely with the implant in 26 cases and controlled with the addition of hypotensive medication in three cases, whereas nine eyes were failures. Eleven patients (29%) underwent intervention for implant repositioning or tube orifice blockage. Thirty-four double- and six single-plate Molteno implants were inserted. Two patients had implants replaced. Seventy-nine percent became aphakic or pseudophakic from their trauma before or at the time of Molteno implant insertion. There were no exclusions resulting from extensive ocular damage. CONCLUSIONS: Insertion of Molteno implants in traumatic glaucoma produced intraocular pressure control at long-term follow-up in 76% of cases.


Subject(s)
Eye Injuries, Penetrating/surgery , Glaucoma/surgery , Molteno Implants , Adolescent , Adult , Aged , Aged, 80 and over , Child , Eye Injuries, Penetrating/complications , Female , Follow-Up Studies , Glaucoma/etiology , Humans , Intraocular Pressure , Male , Middle Aged , Optic Disk/pathology , Postoperative Complications , Prospective Studies , Prosthesis Implantation , Treatment Outcome , Visual Acuity , Visual Fields , Wounds, Nonpenetrating/etiology , Wounds, Nonpenetrating/surgery
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