PubMed Health⌕ Search

Biomedical subjects

D G Charteris

Publications and source records attributed to D G Charteris.

At least 19 recordsLinked to original sources
PubMed2006

The effect of pars plana vitrectomy on cystoid macular oedema associated with chronic uveitis: a randomised, controlled pilot study.

AIM: To evaluate the efficacy of pars plana vitrectomy (PPV) in the management of chronic uveitic cystoid macular oedema (CMO). METHODS: A prospective, interventional, randomised, controlled, pilot study. 23 eyes of 23 patients with CMO secondary to chronic intermediate or posterior uveitis unresponsive to medical treatment were randomised into a surgical (group S) or medical group (group M). 12 patients in group S underwent PPV as opposed to 11 patients in group M who received systemic corticosteroid and/or immunosuppressive treatment during the study period. The primary outcome measures of the study were change in visual acuity and angiographic appearance of CMO at 6 months. RESULTS: Mean visual acuity in group S improved significantly from 1.0 (0.62) at baseline to 0.55 (0.29) at 6 months following vitrectomy (p = 0.011), with five (42%) eyes reaching vision of 20/40 or better. Conversely, mean visual acuity in group M improved only marginally by 0.03 (0.27) (p = 0.785). CMO after vitrectomy was angiographically improved in four (33%) eyes, remained unchanged in seven (58%) eyes, and deteriorated in one (8%) eye. In the medical group, fluorescein leakage decreased in one eye, did not alter in four eyes, and deteriorated in two eyes. CONCLUSION: PPV for macular oedema secondary to chronic uveitis despite angiographic improvement in only one third of the patients, seems to have a significant beneficial effect on visual function. This study provides enough evidence to justify a large scale trial which would define the role of vitrectomy in uveitic macular oedema.

Adult↗
PubMed2006

Visual function and quality of life following vitrectomy and epiretinal membrane peel surgery.

AIM: To investigate the effect of epiretinal membrane (ERM) peel on patients' health related quality of life (HR-QOL) and to explore the association between self reported HR-QOL and conventional measures of visual function. METHODS: The National Eye Institute 25 Item Visual Function Questionnaire (VFQ-25) and the 36 Item Short-Form Health Survey (SF-36) were self administered by 20 patients before and 4 months following surgery. Preoperative and postoperative data collected included logMAR near and distant visual acuity (VA), contrast sensitivity, and metamorphopsia. Questionnaire scores were compared preoperatively and postoperatively and their correlation with traditional methods of visual function evaluation analysed. RESULTS: Postoperatively there was no significant improvement in mean logMAR VA. However, eight (40%) subjects improved by two or more ETDRS lines and nine eyes (45%) reached a final VA of 6/18 or better. Metamorphopsia decreased significantly (p = 0.019) and there was significant improvement in VFQ-25 mean scores for the general vision (p = 0.03), distance activities (p = 0.05), and composite score (p = 0.03). Baseline binocular VA was significantly correlated with baseline VFQ-25 composite score (r = 0.631, p = 0.004). CONCLUSIONS: ERM surgery appears to improve patients' subjective perception of visual function as indicated by higher composite scores in VFQ-25 and improved metamorphopsia in the absence of significant improvement in mean logMAR VA.

Adult↗
PubMed2006

Scleral-fixated posterior chamber intraocular lenses in non-vitrectomized eyes.

OBJECTIVE: To assess the long-term outcome of scleral-fixated sutured posterior chamber intraocular lens (SPCIOL) implantation in non pars plana vitrectomised eyes (1) to evaluate the long-term visual outcome, (2) to identify preoperative risk factors for poor visual outcomes, and (3) to identify the incidence of vitreoretinal complications. METHOD: A retrospective review of 65 eyes, which had not undergone pars plana vitrectomy prior to scleral-fixated SPCIOL implantation. RESULTS: In all, 65 eyes of 61 patients were analysed. The median follow-up period was 16 months (range 1-68 months). At final follow-up, 43 (66%) eyes had unchanged or improved BCVA at final follow-up. A total of 20 (31%) eyes had at least a two line improvement and eight (12%) eyes had at least a two line deterioration in final BCVA. No significant preoperative risk factors for a poor visual outcome were identified. In all, 24 eyes (37%) had per- and postoperative adverse events. These eyes were significantly more likely to have a poor visual outcome. Three eyes (4.6%) had a retinal detachment in the postoperative period, all of which had no perception of light at final follow-up. CONCLUSIONS: This study confirmed that while scleral-fixated SPCIOL intraocular lens implantation might be beneficial, there is a significant risk of per- and postoperative complications leading to loss of best-corrected vision in some eyes.

Adolescent↗
PubMed2005

Assessment of the reproducibility and repeatability of a method of grading macular subretinal fluid using optical coherence tomography.

AIM: To devise a quantative method for the measurement of the extent of macular subretinal fluid using optical coherence tomography (OCT), and to assess the interobserver and intraobserver agreement for this grading system. METHODS: Observational cohort series. Patients were a cohort who underwent retinal detachment surgery over an 18-month period. All patients had OCT scan at 6 weeks after surgery. The scans were graded by two independent observers experienced in OCT interpretation and each grader was masked to the others findings. Observer 1 then regraded the scans on a later day masked to his previous findings. The interobserver and intraobserver agreement was assessed using weighted Kappa (Kw) statistics. RESULTS: In all, 116 patients were analysed. Both the intraobserver and interobserver agreement was very high, with Kw being 0.9631 and 0.9070, respectively. CONCLUSIONS: The grading system for assessment of the extent of macular subretinal fluid using OCT appears to have very good reproducibility and repeatability. We propose that this grading system would be clinically useful when applied to pathologies visible on OCT scan of the macula.

Exudates and Transudates↗
PubMed2005

High resolution imaging of fluorescein patterns in RCS rat retinae and their direct correlation with histology.

To assess the progressive changes in the retinal vascular bed of dystrophic and non-dystrophic Royal College of Surgeons (RCS) rats, retinae, were visualised correlating in vivo fundus fluorescein angiography (FA) with histology. FA was performed in rats aged 5 weeks to 2 years, using a Zeiss confocal scanning laser ophthalmoscope (cSLO). After the final imaging session, a subset of retinae were prepared for flat-mount histology and the vascular bed was visualised using nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) staining. While non-dystrophic rat retinae showed no substantive changes in vascular patterns with age and no demonstrable fluorescein leakage up to at least 1 year, dystrophic rat retinae showed abnormal vascular formations, demonstrable on FA and NADPH-d staining, which could be correlated in single retinae. Hyperfluorescent spots and late angiographic leakage were evident beginning at 10 weeks and progressed in severity with time: they were coincident in distribution with abnormal histological vascular complexes. The ability to monitor the same retina serially makes this approach a valuable tool for studying the dynamics of vascular change in the diseased retina, not only during the course of degeneration but also when assessing efficacy of potential therapeutic approaches.

Animals↗
PubMed2005

Long-term results of the management of silicone oil-induced raised intraocular pressure by diode laser cycloablation.

AIMS/BACKGROUND: To analyse the effectiveness and safety of cyclodiode treatment in eyes with silicone oil-related raised intraocular pressure (IOP) and to correlate the results with clinical features of treated eyes. METHODS: Retrospective review of case notes of all eyes that underwent cyclodiode treatment following injection of silicone oil at Moorfields Eye Hospital between April 1993 and January 2003 and were followed up for at least 1 year. RESULTS: In all, 38 patients were followed up for between 13 and 113 months. Totally, 17 had silicone oil in situ at the time of first treatment. The mean pretreatment IOP was 31.4 mmHg (SD 10.9), reducing to 18.6 mmHg (SD 8.6) at 1 year and to 13.9 mmHg (SD 8.4) at the final follow-up visit (P<0.001). Before treatment, 28 (73.7%) patients were on two or more topical medications. This was reduced to 18 (47.4%) patients (P=0.013) at 1 year and 13 (34.2%) patients (P=0.0007) at final follow-up. Use of oral acetazolamide for glaucoma was reduced from 16 (42.1%) patients precyclodiode to five (13.2%) patients at 1 year (P=0.0034) and three (7.9%) patients at the final visit (P=0.001). Four patients (10.5%) at 1 year and five patients (13.2%) at the final visit had hypotony (defined as IOP of less than 5 mmHg). One patient had enucleation 75 months following first cyclodiode treatment. CONCLUSION: Diode laser photocoagulation can successfully control silicone oil-induced raised intraocular pressure where medical treatment fails. Reduction of IOP appears to be maintained long term.

Acetazolamide↗
PubMed2005

Variability in the content of Indian generic ciprofloxacin eye drops.

BACKGROUND/AIMS: Under-potent generic antibiotics sold in developing world countries may be contributing to positive selection of resistance organisms and to unpredictability in clinical outcome, leading to a loss of confidence among physicians locally. The objective of this study was to determine whether reports of unpredictable outcome for generic ciprofloxacin antibiotic eye drops in India could be the result of inadequate concentration of preparations sold by pharmacies. METHODS: 130 ciprofloxacin eye drop samples sold by pharmacies were collected from seven locations in north, central, and south India; 30 were randomly selected for testing. All samples were assayed using validated methods of reverse phase chromatography and fluorescence detection at a international antibiotic reference laboratory in the United Kingdom. Results were compared with advertised concentrations within the context of internationally accepted variability ranges. RESULTS: In total, six out of the 30 samples tested had ciprofloxacin concentrations lower than the standard advisory ranges of plus or minus 5% of stated content for 3 mg/ml pharmaceutical preparations. The ciprofloxacin content of these eye drops ranged from -36.4% to -16.1% of the stated content (median -21.73%). 24 out of 30 samples were found to be over the standard advisory ranges of plus or minus 5%, at a median of +19.42% (interquartile range (IQR) +14.28 to +25.13). Intra-batch variability of two selected samples was wide at -22.83% to +33.93% (n=11) and -17.07% to +31.20% (n=12). CONCLUSIONS: Approximately 20% of generic ciprofloxacin eye drops, purchased without prescription in India were under-potent. In a number of preparations the antibiotic content was sufficiently low as to have a potential impact on clinical outcome and possibly lead to the selection of resistant isolates in individual patients. More widespread studies are justified to identify the extent of under-potency of widely used generic antibiotic medications in developing countries.

Anti-Infective Agents↗
PubMed2004

Vitrectomy and radial optic neurotomy for central retinal vein occlusion: effects on visual acuity and macular anatomy.

BACKGROUND: Central retinal vein occlusion (CRVO) is a common retinal vascular disorder and a leading cause of visual loss. It is thought to arise from vascular obstruction at the level of the lamina cribrosa. The purpose of the study reported here was to evaluate the potential benefit of radial optic neurotomy (RON) and determine its effect on foveal thickness and macular volume in patients with CRVO. METHODS: We conducted a prospective pilot study of ten patients with CRVO. Visual acuity (VA) score measured with the Early Treatment Diabetic Retinopathy Study chart and the corresponding Snellen equivalent were assessed before and 6 months after surgery. Colour fundus photography, fluorescein angiography (FA) and optical coherence tomography (OCT) were carried out before and at 2, 6, 12 and 24 weeks after surgery. Foveal thickness and macular volumes were assessed using OCT. RESULTS: Visible reperfusion was observed in four of the ten patients at the time of surgery. VA score improved in eight of the ten patients from a median score of 11.50 (range 0-68) to a median score of 35.00 (range 3-79). Macular volumes decreased in six of seven patients from a median of 4.99 mm3 (range 2.68-6.77) to a median of 3.11 mm3 (range 1.11-5.02). Foveal thickness decreased in six of seven patients from a median of 596.50 microm (range 338.50-745.50) to a median of 330.50 microm (range 118-634.50). Six of ten patients developed a chorioretinal venous anastomosis. Macular oedema on OCT persisted in six of ten patients. CONCLUSIONS: We observed an improvement in VA score and a corresponding reduction in foveal thickness and macular volume following RON, but macular oedema persisted in 60% of patients. Whilst optimisation of patient selection criteria remains a challenge, this pilot study suggests that RON has a beneficial effect on VA in patients presenting with CRVO.

Adult↗
PubMed2004

Late onset vitreoretinal complications of regressed retinopathy of prematurity.

AIM: To report the clinical findings, management, and outcomes in eyes undergoing surgery for regressed retinopathy of prematurity (ROP) with vitreoretinal complications. METHOD: Retrospective review of 40 eyes of 32 patients with regressed ROP who presented between 1989 and 2001 at two UK referral centres. RESULTS: Of 29 eyes presenting with rhegmatogenous retinal detachment (RRD), 15 initially underwent a scleral buckling procedure and 14 initially underwent vitrectomy with or without additional buckling. Primary surgery was anatomically successful in 11/15 eyes that underwent a non-vitrectomy retinal detachment repair and 8/14 that required vitrectomy. The final reattachment rate after reoperation was 28/29 eyes. Median visual acuity improved from 6/60 to 6/36 following retinal detachment repair. A further 11 eyes of eight patients from this series underwent prophylactic surgery, laser, or cryotherapy for predisposing vitreoretinal pathology and/or retinal breaks, all of which were stabilised. CONCLUSIONS: In eyes with RRD and signs of regressed ROP successful reattachment of the retina can be achieved using either vitrectomy or external surgery with an associated overall improvement in visual acuity. A range of external and closed microsurgical approaches is required to effectively deal with the diverse manifestations of regressed ROP.

Adolescent↗
PubMed2004

Silicone oil concentrates fibrogenic growth factors in the retro-oil fluid.

AIM: To determine whether silicone oil concentrates protein and growth factors in the retro-oil fluid. METHODS: A laboratory analysis of intraocular fluid and vitreous specimens obtained from patients undergoing removal of silicone oil, revision vitrectomy, or primary vitrectomy for macular hole, proliferative vitreoretinopathy (PVR), or retinal detachment. Patients were prospectively recruited from routine vitreoretinal operating lists. Vitreous cavity fluid and vitreous samples were analysed for the presence of transforming growth factor beta (TGF-beta2), basic fibroblast growth factor (bFGF), interleukin 6 (IL-6), and total protein using either commercially available enzyme linked immunosorbent assays (ELISA) or protein assay kits. RESULTS: The median levels of bFGF, IL-6, and protein in the retro-oil fluid were raised (p<0.05) compared to all the other vitreous and vitreous cavity fluid samples. bFGF, IL-6, and protein levels were raised in PVR vitreous compared to non-PVR vitreous. TGF-beta2 levels were not significantly raised in retro-oil fluid or in PVR vitreous. CONCLUSIONS: The concentration of fibrogenic (bFGF) and inflammatory (IL-6) growth factors and protein is raised in retro-silicone oil fluid. This may contribute to the process of retro-oil perisilicone proliferation and subsequent fibrocellular membrane formation.

Enzyme-Linked Immunosorbent Assay↗
PubMed2003

Vitreous surgery in the management of chronic endogenous posterior uveitis.

OBJECTIVES: There is evidence that pars plana vitrectomy (PPV) has a beneficial effect on the clinical course of chronic endogenous posterior uveitis (EPU) possibly by physically removing any resident inflammatory cells with the vitreous. We assessed the anatomical and therapeutic effects of PPV performed on patients with chronic EPU for any indication. PATIENTS AND METHODS: Retrospective review of 41 eyes of 38 consecutive patients with EPU who underwent a PPV for any reason, over a 5-year period. The mean age of the patients was 36.2 years, 46% of the eyes had intermediate uveitis, 32% panuveitis, and 22% posterior uveitis. The visual acuity, disease activity, and the requirement for medications to control it were recorded for 12 months pre- and postoperatively. RESULTS: Overall, 61% of the eyes gained more than 2 Snellen lines (P<0.001) and the incidence of cystoid macular oedema (CMO) significantly reduced from 44 to 20% (P<0.05). Postoperatively, there was a significant decrease in the recurrence rate of intermediate uveitis, posterior uveitis, and panuveitis (P<0.001). The use of systemic and local depot immunosuppressive agents did not change over the study period, although the use of topical agents increased (P<0.05). CONCLUSION: PPV appears to have a beneficial effect on the clinical course of EPU in selected cases. This may be mediated by the physical clearance of inflammatory debris, the anti-inflammatory effect of replacing vitreous by aqueous humour, by a reduction of CMO and/or the anatomical correction of sight-threatening retinal pathology.

Adolescent↗
PubMed2003

Laser photocoagulation alters the pattern of staining for neurotrophin-4, GFAP, and CD68 in human retina.

AIMS: To investigate the staining pattern of neurotrophin-3 (NT3), neurotrophin-4 (NT4), and brain derived neurotrophic factor (BDNF) as well as glial fibrillary acid protein (GFAP) and CD68 in lasered human retina. METHODS: Retinal laser photocoagulation was performed on four patients (two males, two females) with choroidal malignant melanoma 1-6 days before enucleation. Three other enucleated eyes with malignant melanoma and three normal cadaveric donor eyes were used as controls. Immunohistochemistry was performed to investigate the pattern of staining of NT3, NT4, BDNF, GFAP, and CD68 in 7 mm sections of fixed specimens. RESULTS: Expression of NT4 was detected in the inner and outer nuclear layers of all the retinal sections examined but no NT3 and BDNF staining was seen. NT4 staining was found to be less intense in lasered and melanoma controls compared to normal cadaveric donor retinas. There was an upregulation of GFAP expression in both lasered and control eyes with melanoma in comparison with normal controls. CD68 staining was only observed in retinal pigment epithelium and choroid of lasered eyes. CONCLUSION: NT4 is expressed in inner and outer nuclear layers of normal human retina and its expression is downregulated following laser photocoagulation. This occurs in parallel with an increased expression of GFAP suggesting that reactive changes in Muller cells may be responsible for reduced NT4 staining. Expression of CD68 at the site of laser injury is consistent with a wound healing process as a response to local damage.

Aged↗
PubMed2002

Proliferative vitreoretinopathy-developments in adjunctive treatment and retinal pathology.

Proliferative vitreoretinopathy (PVR) remains a difficult management problem despite advances in vitreoretinal surgery. There is still a significant incidence of PVR in rhegmatogenous retinal detachment and other forms of retinal disease. Surgery for PVR now has a high anatomical success rate although visual results are often disappointing. The use of adjunctive treatments to prevent cellular proliferation holds promise for the prevention of PVR or recurrences after surgery. Control of proliferation and strategies aimed at improving visual outcome are important areas of future research in PVR and other forms of retinal disease. Studies of the intraretinal and peri-retinal pathology of PVR have demonstrated characteristic changes which may have a significant influence on visual outcome and surgical management.

Chemotherapy, Adjuvant↗
PubMed2002

Animal models of retinal detachment and reattachment: identifying cellular events that may affect visual recovery.

Retinal detachment continues to be a significant cause of visual impairment, either through the direct effects of macular detachment or through secondary complications such as subretinal fibrosis or proliferative vitreoretinopathy. Animal models can provide us with an understanding of the cellular mechanisms at work that account for the retinopathy induced by detachment and for the generation of secondary effects. As we understand the mechanisms involved, animal models can also provide us with opportunities to test therapeutic agents that may reduce the damaging effects of detachment or improve the outcome of reattachment surgery. They may also reveal information of use to understanding other causes of blindness rooted in retinal defects or injuries. Understanding the effects of detachment (and reattachment) are likely to become even more important as surgeons gain skills in subretinal surgical techniques and macular translocation, both of which will generate short-lived detachments. Here we discuss the fundamental events that occur after detachment, present changes associated with reattachment, and discuss retinal changes that may affect the return of vision.

Animals↗
PubMed2001

How to predict proliferative vitreoretinopathy: a prospective study.

PURPOSE: To determine prospectively the accuracy of a predictive risk formula for the development of postoperative proliferative vitreoretinopathy (PVR) when applied in a clinical setting. DESIGN: Prospective noncomparative interventional case series. PARTICIPANTS: Two hundred nineteen subjects undergoing primary vitrectomy for rhegmatogenous retinal detachment were studied. METHOD: By use of a formula-based discriminant rule, subjects were classified as either high or low risk for the development of PVR. All subjects were followed prospectively. OUTCOME MEASURES: Development of postoperative PVR as defined by the updated the Retina Society Classification. RESULTS: Complete data were available on 212 of 219 subjects. There were 130 subjects identified as low risk and 82 subjects as high risk; 9.2% of the low-risk (12 of 130) compared with 28% (23 of 82) of the high-risk subjects had postoperative PVR develop. This difference was statistically significant (P < 0.001). CONCLUSIONS: Our study has shown that using a clinical model it is possible to identify subjects at greater risk of PVR developing after primary vitrectomy.

Adolescent↗