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David G Charteris

Publications and source records attributed to David G Charteris.

At least 19 recordsLinked to original sources
PubMed2006

Functional outcome and prognostic factors in 304 eyes managed by retinectomy.

BACKGROUND: This study was undertaken to relate the anatomic and functional results of patients who underwent retinectomy for complex retinal detachment (RD) to preoperative prognostic variables. METHODS: Three hundred and four eyes of 302 patients whose surgery involved retinectomy were included in the analysis. All eyes had established proliferative vitreoretinopathy (PVR grade C). The main outcome measures were (1) postoperative visual acuity of 6/24 or better, (2) status of the retina at the end of follow-up, and (3) incidence of hypotony whilst under review. RESULTS: PVR was secondary to rhegmatogenous RD in 237 eyes (78%), posterior trauma in 51 eyes (16.8%), tractional RD in vasoproliferative vasculitides in 12 eyes (4%), acute retinal necrosis in 2 eyes and endophthalmitis in 2 eyes. Complete reattachment rate after one operation was 51%, with final complete reattachment success rate of 72%. The visual acuity improved in 138 eyes (45%), remained the same in 73 eyes (24%) and became worse in 89 cases (29%). Postoperative visual acuity of 6/24 or better was significantly associated with preoperative vision, the duration of silicone oil tamponade, silicone oil removal and retinectomy size. There was also some evidence of association between visual outcome and the number of clock hours of retinal detachment. Final retinal attachment was significantly associated with silicone oil removal and preoperative vision, and final hypotony was significantly associated with silicone oil removal. The incidence of sympathetic ophthalmia in our study was 0.09% (one case). CONCLUSIONS: Good functional outcome is possible following retinectomy surgery despite advanced pathology and often multiple surgical procedures. Retinal redetachment as a result of reproliferation and hypotony appear to be the main reasons for anatomical and functional failure. The clinical features we have identified as good indicators for improved final visual acuity such as shorter tamponade duration, removal of silicone oil, smaller retinectomy size, fewer previous operations and better preoperative vision are surrogate markers of less advanced PVR and should prompt retinal surgeons to consider retinectomy at an earlier stage in the process of PVR development. Clinicians should be aware of the small risk of sympathetic ophthalmia from complex retinal surgery.

Adolescent↗
PubMed2006

Identification of ganglion cell neurites in human subretinal and epiretinal membranes.

AIM: To determine whether neural elements are present in subretinal and epiretinal proliferative vitreoretinopathy (PVR) membranes as well as in diabetic, fibrovascular membranes removed from patients during vitrectomy surgery. METHODS: Human subretinal and epiretinal membranes of varying durations were immunolabelled with different combinations of antibodies to glial fibrillary acidic protein, vimentin, neurofilament protein and laminin. RESULTS: Anti-neurofilament-labelled neurites from presumptive ganglion cells were frequently found in epiretinal membranes and occasionally found in subretinal membranes. In addition, the neurites were only observed in regions that also contained glial processes. CONCLUSIONS: These data demonstrate that neuronal processes are commonly found in human peri-retinal cellular membranes similar to that demonstrated in animal models. These data also suggest that glial cells growing out of the neural retina form a permissive substrate for neurite growth and thus may hold clues to factors that support this growth.

Diabetic Retinopathy↗
PubMed2006

Optical coherence tomography analysis of the macula after scleral buckle surgery for retinal detachment.

OBJECTIVE: To define the incidence, pattern, duration, and clinical consequences of persistent localized submacular fluid after scleral buckle surgery for retinal detachment (RD). DESIGN: Prospective observational cohort series. PARTICIPANTS: Ninety-eight patients were identified and recruited to the study. METHODS: Patients aged > or =18 years undergoing scleral buckle surgery for uncomplicated primary RD over an 18-month period were recruited. All patients underwent clinical examination and optical coherence tomography (OCT) scan of the macula preoperatively and at 6 weeks postoperatively. Those patients who had an abnormality on OCT 6 weeks after surgery underwent follow-up with repeat of the study investigations at 3, 6, 9, 12, and 18 months after surgery until the abnormality resolved. If no abnormality was seen at the 6-week examination, no further investigation was undertaken. MAIN OUTCOME MEASURE: Presence of submacular fluid on OCT 6 weeks after surgery. Other outcome measures were duration of persistent fluid and associations with poor visual outcome, type, or duration of detachment. RESULTS: Of the 98 patients recruited into the study, 54 (55%) had subretinal fluid (SRF) on OCT 6 weeks after surgery. We identified 3 patterns of submacular fluid: confluent fluid, a single discrete bleb of fluid, and multiple blebs of fluid. Fluid was associated with delayed visual recovery. Of those with SRF, 78% had persistent fluid at 6 months; resolution of fluid took a median of 10 months and was associated with an improvement in vision. CONCLUSIONS: Optical coherence tomography is a useful noninvasive diagnostic method that can detect SRF not seen on clinical examination. Persistent SRF 6 weeks after scleral buckle surgery occurs in approximately half of patients, may persist for many months, and can cause delayed visual recovery.

Adult↗
PubMed2006

Immunopathology of intraocular silicone oil: retina and epiretinal membranes.

AIMS: To determine the inflammatory response in retina and epiretinal membranes after intraocular silicone oil tamponade. METHODS: 14 proliferative vitreoretinopathy (PVR) epiretinal membranes, 33 retro-oil epiretinal membranes, 19 retinectomies, 14 retro-oil retinectomies and 37 idiopathic epiretinal membranes (controls) underwent immunohistochemical analysis using the avidin-biotin complex technique and a panel of monoclonal and polyclonal antibodies. The number of positive cells counted in five 0.5 mm diameter fields of immunohistochemical sections was graded on a score of 1-4. RESULTS: Macrophage cell counts were significantly greater in membranes with a history of exposure to silicone oil (p<0.001). An inflammatory response could be observed within 1 month of silicone oil exchange, and the intensity seemed to be unrelated to the duration of exposure. Macrophages were confined to epiretinal membranes on the surface of retinectomy specimens in 10 of 14 cases and intraretinal macrophages were observed only in specimens with gliotic retina. T and B lymphocytes were rarely seen in the specimens examined. Marked glial cell up regulation was observed in 11 of 16 retinectomy specimens and in 8 of 11 retro-oil retinectomies. Glial cell content was variable in the membranes, but there was a trend of increased presence after exposure to silicone oil. CONCLUSION: This study has shown that the use of silicone oil is accompanied by an inflammatory reaction, primarily mediated by bloodborne macrophages. This response can be observed within 1 month of silicone oil injection and continues after silicone oil removal. Retinal surgeons should be aware of the potential secondary effects of intraocular silicone oil when they are considering its use (and removal) in vitreoretinal surgery.

B-Lymphocytes↗
PubMed2006

Immunopathology of intraocular silicone oil: enucleated eyes.

AIMS: To characterise the distribution of silicone oil in ocular tissues in globes enucleated after complicated retinal detachment, and to document the distribution and nature of any associated inflammatory response. METHOD: 9 enucleated globes that had previously undergone retinal detachment surgery with silicone oil and 7 control globes that had undergone enucleation after retinal detachment surgery (n = 2) or ocular trauma (n = 5) were studied. Sections were histologically examined using light microscopy to document the distribution of silicone oil in ocular tissues. Immunohistochemical analysis was carried out using the ABC technique and a panel of monoclonal and polyclonal antibodies. Electron microscopy was undertaken to observe the penetration of silicone oil in the trabecular meshwork of the anterior chamber drainage angle. RESULTS: Silicone oil was distributed throughout the globes-notably in the iris, ciliary body, retina, trabecular meshwork and epiretinal membranes. Focal areas of intraretinal silicone were associated with disorganised retinal architecture, retinectomy sites or subretinal oil. The distribution of macrophages was closely related to the distribution of silicone oil. T and B lymphocytes were not associated with silicone oil unless additional pathology was also present-for example, cyclitic membrane or uveitis. One of the nine eyes had silicone oil present in the optic nerve. In the control globes, the inflammatory response was mediated primarily by macrophages and T lymphocytes, and was less marked than that observed in the silicone oil globes. CONCLUSION: This study shows that silicone oil may be sequestered in varied ocular tissues and is associated with localised inflammation mediated by macrophages.

Adolescent↗
PubMed2006

Optical coherence tomography analysis of the macula after vitrectomy surgery for retinal detachment.

OBJECTIVE: To define the incidence, duration, and clinical associations of persistent localized submacular fluid after pars plana vitrectomy (PPV) retinal detachment surgery. DESIGN: Observational cohort series. PARTICIPANTS: One hundred patients were identified and recruited into the study. METHODS: Patients aged 18 years and older who had undergone PPV and gas as a primary procedure for rhegmatogenous retinal detachment and postoperative follow-up were recruited from February through August 2004. All patients underwent clinical examination, optical coherence tomography (OCT) scan of the macula, and retinal thickness analysis scan of the macula. Those patients in whom an abnormality was seen on OCT at 6 weeks after surgery underwent follow-up with repeat of the study investigations at 3, 6, 9, 12, and 18 months after surgery until the abnormality resolved. If no abnormality was seen at the 6-week examination, no further investigation was undertaken. Demographic data, including detachment characteristics, were collected retrospectively from the patient case notes. MAIN OUTCOME MEASURES: The principle outcome measure was the presence of subretinal fluid (SRF) on OCT at 6 weeks after surgery. Other outcome measures included duration of persistent fluid and association with visual outcome and type and duration of detachment. RESULTS: One hundred patients were recruited; 15 of these had SRF on OCT performed at 6 weeks after surgery. Subretinal fluid was associated with significantly worse visual acuity (VA) at 6 weeks (P = 0.033, Wilcoxon rank-sum); those with SRF had a median VA of 0.4, and those with no SRF had a median VA of 0.3. The fluid took a median of 5.5 months to resolve. Seven patients had combined PPV and scleral buckle surgery; none of these had fluid at 6 weeks. CONCLUSIONS: Optical coherence tomography is a useful noninvasive diagnostic method that can detect SRF not appreciated on clinical examination. Persistent SRF after PPV and gas surgery occurred in 15% of patients in this study and was still present in 53% of these at 6 months. The presence of SRF at 6 weeks after surgery was associated with a poorer visual outcome at this time point.

Adult↗
PubMed2006

Intraretinal and periretinal pathology in anterior proliferative vitreoretinopathy.

OBJECTIVES: To determine the intraretinal and periretinal pathological changes in early anterior proliferative vitreoretinopathy (APVR). DESIGN: Observational case series. PARTICIPANTS: Eighteen patients undergoing retinectomy for APVR. METHODS: Retinectomy specimens removed at vitrectomy surgery were analysed by (a) semithin light microscopy, (b) immunohistochemistry and (c) electron microscopy. RESULTS: The specimens showed consistent outer retinal degenerative changes, marked Muller cell hypertrophy and glial continuity to epiretinal membranes. Photoreceptor outer and inner segments were markedly disrupted and occasional photoreceptor nuclear had pyknosis and chromatin clumping consistent with apoptosis. Muller cells expressed upregulated levels of glial fibrillary acid protein (GFAP) and extended through glial bridges to complex epiretinal membranes which in some areas had a bilaminar structure with a glial-negative inner lamina. CONCLUSION: Retinal degeneration and photoreceptor apoptosis occur in retinal detachment complicated by proliferative vitreoretinopathy (PVR), although during the early stages of the process neural retinal cells remain present, suggesting potential for recovery. The intraretinal glial response appears to be centrally involved in the formation of contractile epiretinal membranes. The retina retains the capacity for a degree of functional recovery following surgery for PVR. Surgical separation of anterior epiretinal membranes in PVR may be difficult and incomplete and alternative surgical strategies may be necessary to prevent recurrence.

Adolescent↗
PubMed2006

Long-term outcome of combined pars plana vitrectomy and scleral fixated sutured posterior chamber intraocular lens implantation.

PURPOSE: To investigate the long-term visual outcome and the complication rate following transscleral suture fixation of posterior chamber intraocular lenses (sutured PC-IOLs). DESIGN: A retrospective case-series descriptive study. METHODS: Records of patients who underwent combined pars plana vitrectomy and sutured PC-IOLs at Moorfields Eye Hospital and who had at least 12 months of follow-up were examined for recorded complications. RESULTS: Sixty-one eyes of 48 patients (33 males and 15 females) were identified and included in the analysis, with mean follow-up of 6 years. The mean final best-corrected visual acuity remained at preoperative levels (P=.211) and was largely determined by the underlying ocular pathology before sutured PC-IOL. Overall 30 of 61 (49%) eyes, two or more procedures were performed to reverse a significant peri- or postoperative complication. Breakage of polypropylene sutures was the main indication accounting for 17 of 30 (57%) of those reoperations. Subgroup analysis showed that younger patients were more likely to suffer the above complication (P=.009). The multivariate analysis also showed that longer follow-up was significantly associated with suture breakage (P=.014), with the mean time to breakage approximately 4 years after surgery. CONCLUSIONS: Long-term follow-up of patients undergoing sutured PC-IOLs appears to be associated with a high rate of postoperative complications and significant need for further surgery, which should be discussed during their informed consent process.

Adolescent↗
PubMed2005

Microglial cell activation following retinal detachment: a comparison between species.

PURPOSE: To compare the activation of microglia in response to retinal detachment in four species. METHODS: Experimental detachments were created in cats, rabbits, and ground squirrels and the retinas harvested 1, 3, 7, or 28 days later. Retinal reattachments of 28 days in duration were also performed in cats following a 3-day detachment. Human tissue was obtained during reattachment surgery. Microglia and macrophages were labeled with the lectins Griffonia simplicifolia and Ricinus communis and the antibody CD11b. Müller cell and photoreceptor responses were followed immunocytochemically on the same tissue sections labeled with microglial markers. Images were collected by laser scanning confocal microscopy. RESULTS: Lightly labeled microglia were observed primarily in the inner retina of control tissue. In the cat and rabbit, a progressive increase in the number of labeled cells occurred in the outer retina beginning at 1 day of detachment. In both long term human and cat detachments numbers of microglia were elevated throughout the retina. This is in contrast to the rabbit and ground squirrel retinas where microglial activation was dramatically diminished in longer term detachments. Presumptive macrophages (anti-CD11b labeled cells) occurred only in the subretinal space. Retinal reattachment in cats significantly attenuated the response except in areas of poor outer segment regeneration. CONCLUSIONS: The robust microglial response to retinal detachment is an indicator of the importance of this cell type in the overall response of the retina. Our data suggest that the feline retina is a particularly appropriate model system for understanding this response in humans. Inhibiting the microglial response in that species should help us understand more precisely its potential role in photoreceptor survival in human pathology.

Animals↗
PubMed2005

Analysis of the macula with optical coherence tomography after successful surgery for proliferative vitreoretinopathy.

OBJECTIVE: To use optical coherence tomography to assess the in vivo pathologic findings associated with incomplete visual recovery in patients who have undergone anatomically successful surgery to treat proliferative vitreoretinopathy. METHODS: Eligible patients were recruited in vitreoretinal outpatient clinics between April 1, 2002, and July 31, 2003. Patients were included who had undergone anatomically successful vitreoretinal surgery to treat proliferative vitreoretinopathy and, at least 3 months after surgery, had postoperative vision worse than expected (< or =6/12) with no identifiable cause at clinical examination. Patients underwent optical coherence tomography, stereo fundus fluorescein angiography was performed in a cohort of patients, and angiographic findings were compared with those on the optical coherence tomograms. Relevant clinical data were collected retrospectively from patient case notes. RESULTS: A total of 35 patients were recruited. Optical coherence tomograms revealed cystoid macular edema in 23 patients (66%) but did not identify any other specific intraretinal disease. Location of edema (outer or inner retina), determined with stereo fundus fluorescein angiography and optical coherence tomography, correlated well. CONCLUSIONS: Optical coherence tomography is a useful diagnostic tool for assessing poor postoperative visual acuity and can reveal disease undetected at clinical examination. Cystoid macular edema is a common finding on optical coherence tomograms in eyes with incomplete visual recovery after anatomically successful surgery to treat proliferative vitreoretinopathy.

Adolescent↗
PubMed2005

Staining and peeling of the internal limiting membrane in the cat eye.

PURPOSE: To investigate the cat vitreomacular interface using trypan blue (TB) and indocyanine green (ICG) and to determine the validity of the cat model in terms of staining and peeling of the internal limiting membrane (ILM). METHODS: Lensectomy and vitrectomy were performed in four eyes of two cats. The ILM of two eyes was stained with TB (0.15%). ILM peeling was performed in one eye. Two eyes were stained with ICG (0.5%). One eye was illuminated for 3 min. Light and transmission electron microscopy and confocal microscopy were performed. RESULTS: Clinically, both dyes stained the cat ILM similar to human ILM. TB staining resulted in a normal ultrastructure and antigenity of the retina. ILM peeling was associated with intraretinal bleeding. There were fragments of Müller cells adherent to the retinal side of the ILM, and Müller cell endfeet were ruptured and avulsed. ICG staining of the ILM followed by illumination caused severe inner retinal damage. ICG without illumination resulted in focal ILM detachments associated with tearing of Müller cell endfeet. CONCLUSIONS: The cat can be used as a model to study the effect of TB and ICG on the central area of the cat retina, as previous results from clinical and experimental postmortem settings in human eyes were confirmed in the current study. Peeling of the ILM as a sheet as performed in human macular surgery is not feasible. Differences in the ultrastructure of the ILM and a strong adhesion of the ILM to Müller cell endfeet may account for this observation.

Animals↗
PubMed2005

Glial remodeling and neural plasticity in human retinal detachment with proliferative vitreoretinopathy.

PURPOSE: To investigate glial remodeling and neuronal plasticity in adult human retinal detachment complicated by proliferative vitreoretinopathy (PVR) and to grade pathologic changes with a severity scoring system. METHODS: Sixteen full-thickness retinectomy specimens obtained at retinal relaxing surgery for PVR were fixed in 4% paraformaldehyde immediately after excision and compared to similarly processed normal donor retinas. Agarose-embedded sections (100-microm-thick) were double labeled for immunohistochemistry by confocal microscopy, with antibodies against rod opsin and GFAP; vimentin and M/L-cone opsin; calbindin D and S-cone opsin; and cytochrome oxidase and synaptophysin. These staining patterns formed the basis of a retinal pathology scoring system, and immunohistochemistry was also used to detect CD68, neurofilaments, protein kinase C, growth-associated protein-43, and a pan-cone-specific enzymatic marker. Morphology was also assessed by light microscopy of resin-embedded semithin sections. RESULTS: Prolonged detachment was characterized by photoreceptor degeneration and intracellular redistribution of opsin proteins to the plasma membrane in the outer nuclear layer (ONL). Remodeling of rod synaptic terminals was characterized by terminal retraction and also by axon extension to the inner retina in most specimens. Rod bipolar cell dendrites extended into the ONL, as did fine, horizontal cell processes. Large ganglion cells showed upregulated neurofilament and GAP-43 expression, with neurites sprouting from somata and axon collaterals. Anti-cytochrome oxidase labeling of surviving inner segments was reduced but detectable in all specimens, as was anti-calbindin D labeling of horizontal and amacrine cells. All specimens demonstrated a marked upregulation of Muller cell and astrocyte expression of GFAP and vimentin. More severe degenerative changes correlated with trauma and prolonged detachment duration when scored according to this system. CONCLUSIONS: The neural and glial components of detached neurosensory retina complicated by PVR exhibit pathology that changes characteristically with increasing detachment severity. Even in advanced degeneration, most of the structural motifs necessary for functional recovery are retained. Evidence of remodeling in the first-, second-, and third-order neurons of detached adult human retina may represent an attempt to re-establish synaptic connectivity.

Adolescent↗
PubMed2004

Visual function and subjective perception of visual ability after macular hole surgery.

PURPOSE: To evaluate the functional and anatomical results of macular hole surgery and to explore its effect on patients' Health-Related Quality Of Life (HR-QOL) and to investigate the associations between self-reported HR-QOL and conventional measures of visual function. DESIGN: Case series. 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 30 patients before and 4 months after macular hole surgery. Preoperative, intraoperative, and postoperative clinical data were collected including visual acuity, contrast sensitivity, and metamorphopsia. Multi-item scales rating different aspects of HR-QOL were compared before and after surgery, and their correlation with traditional methods of outcome evaluation was analyzed. RESULTS: Macular hole closure was achieved in 26 patients (87%). Mean LogMAR visual acuity improved by 6 +/- 10 letters for distance and 7 +/- 12 letters for near. Metamorphopsia was reduced by a mean of 35 +/- 70 squares on Amsler chart, and Pelli-Robson contrast sensitivity decreased by a mean of -0.09 +/- 0.3 log units postoperatively. The VFQ-25 composite score as well as scale scores associated with general vision, near vision, vision-related mental health, and role difficulties were significantly improved (P < .05) after successful closure of macular hole. Conversely out of the eight SF-36 health concepts, limitation in usual role activities because of emotional problems was the only one that significantly improved postoperatively. Both baseline and postoperative best-corrected visual acuity significantly correlated with most of the VFQ subscale scores before and after surgery, respectively. CONCLUSIONS: In this case-series, macular hole surgery appears to have a beneficial effect on patients' subjective perception of visual function. The use of vision-targeted health status questionnaires in conjunction with detailed clinical examination provides a more comprehensive overview of individuals' daily well-being after surgical intervention. Further controlled studies are required to confirm our findings.

Aged↗
PubMed2004

A randomized controlled trial of combined 5-fluorouracil and low-molecular-weight heparin in management of established proliferative vitreoretinopathy.

OBJECTIVE: To determine the efficacy of a combination of 5-fluorouracil and low-molecular-weight heparin (LMWH) to improve the outcome of surgery for established proliferative vitreoretinopathy (PVR). DESIGN: Double-masked, prospective, randomized, placebo-controlled clinical trial. SETTING: Three tertiary-referral teaching hospital vitreoretinal surgical units. PATIENTS: One hundred fifty-seven patients with established PVR (grade C, anterior or posterior) undergoing vitrectomy surgery. INTERVENTION: All patients underwent vitreoretinal surgery and silicone oil exchange with or without membrane peeling and/or retinectomy. Patients were randomly allocated to perioperative infusion with or without 5-fluorouracil (200 microg/ml) and LMWH (5 IU/ml) in Hartmann's solution for 1 hour. OUTCOME MEASURES: The primary outcome measure was defined as posterior retinal reattachment after removal of silicone oil without any reoperations at 6 months. Secondary outcome measures recorded were posterior retinal reattachment, localized/tractional retinal detachment, visual acuity, macular pucker, hypotony, glaucoma, keratopathy, and cataract. Removal of silicone oil and reoperations were also recorded. RESULTS: Overall, at 6 months 84% of patients had full retinal reattachment and 94% had stable posterior retinal reattachment. There was no significant difference in success in the primary outcome measure (56%, treatment group; 51%, placebo group; P = 0.59) or in secondary outcome measures or rates of complications. Secondary macular pucker occurred less often in the treatment group (6% vs. 17% at 6 months, P = 0.068). CONCLUSIONS: A perioperative infusion of combined 5-fluorouracil and LMWH does not significantly increase the success rate of vitreoretinal surgery for established PVR.

Aged↗
PubMed2004

Resources involved in managing retinal detachment complicated by proliferative vitreoretinopathy.

PURPOSE: To report the differences in cost of treatment and outcome in retinal detachment (RD) cases with and without proliferative vitreoretinopathy (PVR). METHODS: Analysis of clinical trial databases of RD observed in 190 eyes of 190 patients. Eyes were classified as no PVR, developing PVR, or established PVR. For each eye, total cost of treatment undertaken on Moorfields Eye Hospital vitreoretinal unit, final retinal status, and best-corrected visual acuity were recorded. RESULTS: Management of patients who developed PVR involved approximately double the resources of RD without PVR. Eyes with pre-exiting PVR had similar resource input to those with RD without PVR. Patients who developed PVR had a mean of 3.7 operations (including subsequent cataract surgery) compared to 1.8 and 2.1 respectively for noncomplicated RD and pre-existing PVR. Anatomic success and visual outcome was significantly worse in eyes with PVR. CONCLUSIONS: Treatment of eyes that developed PVR after initial surgery cost significantly more than eyes with no PVR or established PVR (P < 0.01). Improvements in the management of RD aimed at preventing PVR and advances in PVR treatment may have significant financial as well as clinical benefits.

Adolescent↗