Biomedical subjects

R Sanders

Publications and source records attributed to R Sanders.

At least 19 recordsLinked to original sources

PubMed2006

The effect of aspirin and warfarin therapy in trabeculectomy.

AIM: The management of patients on antiplatelet and anticoagulation therapy (APACT) in glaucoma surgery currently has no specific recommendations. We aimed to establish the risk of haemorrhagic complications and surgical outcome in patients on APACT in glaucoma surgery. METHODS: We retrospectively examined 367 consecutive trabeculectomies performed between 1994 and 1998. Preoperatively 60 (16.4%) patients were on APACT (55 on aspirin and five on warfarin). The incidence of hyphaema and haemorrhagic complications between patients with and without APACT was documented. Surgical success was defined in two categories as an intraocular pressure (IOP) <21 mmHg and an IOP <16 mmHg 2 years following trabeculectomy with and without antiglaucoma medication. RESULTS: None of the patients on aspirin suffered significant intra or postoperative haemorrhage. Aspirin was associated with a significantly higher risk of hyphaema (P=0.0015) but this was not found to significantly affect IOP control at 2 years. Patients on warfarin suffered haemorrhagic complications and trabeculectomy failure. CONCLUSIONS: Aspirin appears to be safe to continue with during trabeculectomy. Patients on aspirin have an increased risk of hyphaema following trabeculectomy. This however does not appear to affect surgical outcome. Warfarinised patients are at risk of serious bleeding complications. They require careful monitoring pre- and postoperatively and are at risk of trabeculectomy failure.

Adolescent↗

PubMed2006

Psychological and social factors in reconstructive surgery for hemi-facial palsy.

This paper examines the psychological and social impact of reconstructive surgery for hemi-facial palsy and considers psychosocial factors which may be associated with patient satisfaction. It reports a retrospective study in which 106 adults were assessed using primarily qualitative methods. All participants had undergone two-stage reconstruction using vascularised free muscle grafts, with all procedures having been carried out by the same surgeon. The participants were all at least 12 months post-surgery. They were assessed using demographic questionnaires, the hospital anxiety and depression scale (HADS) and the facial paralysis evaluation measure (FPEM). In addition, all participants were interviewed using a semi-structured format, the interviews were recorded verbatim and the transcripts were analysed using thematic analysis. Of the total study group, 67% had acquired facial palsy. The mean age of the total group was 44.7 years and 67.9% were female. As a group they were rather less depressed than the normal population with similar levels of anxiety to population norms. The primary motivation for surgery was appearance rather than function. Using interview data in addition to the FPEM, satisfaction with the process and outcome of surgery was assessed. Thirty five percent were very satisfied with both process and outcome, 34% were satisfied with the outcome but found the treatment process stressful, 15.1% were not entirely satisfied with process or outcome but felt surgery had been worthwhile as there had been some improvement. The remainder were very dissatisfied with both process and outcome and regretted having undergone surgery. There was no significant association between dissatisfaction and anxiety, the cause of the acquired palsy, longevity prior to surgery, gender nor whether the condition was acquired or congenital. There was a significant relationship with depression, in that those who were suffering from depression were more likely to be dissatisfied with surgery. Participants were asked in interview about social pressures and comments or remarks made by others about their condition. The majority (89.6%) of the total study group reported intrusive questions by acquaintances and strangers, with more than half of these being distressed by such questions. Following surgery, there was a significant reduction in the incidence of these questions. There was no relationship between distress in response to these questions prior to surgery and dissatisfaction with surgery. However, 27.4% also reported aggressive hurtful comments before surgery with a minimal improvement in incidence following surgery. These participants also reported consistent patterns of social avoidance and social isolation before and after surgery, and were more likely to be depressed than the rest of the study group. They were significantly more likely to be dissatisfied with surgery (p=.016). It is recommended that patients are screened and counseled prior to surgery to identify such problems and referred for psychological treatment in order to ensure they gain maximum benefit from reconstructive surgery.

Adult↗

PubMed2005

Long term follow-up of c-myc, p53 and proliferation measurements in malignant melanoma.

AIMS: We report a prospective study examining the prognostic significance of the c-myc oncoprotein, p53 tumour suppressor gene and proliferation rate measurements in malignant melanoma. METHODS: Flow cytometry (FCM) was used to measure the expression of c-myc, p53 and proliferation parameters in patients who had received an injection of the thymidine analogue bromodeoxyuridine prior to surgery. RESULTS: Sixty-seven patients had successful FCM measurements of the three parameters. c-myc was detected in 97% of patients with a median cell positivity of 62%. The median p53 positivity was 13%. The median potential doubling time (T(pot)) of the tumours wasf 9.4 days. In univariate analysis, each of the parameters showed an association with survival in metatstatic disease with rapid proliferation (p=0.006) or overexpression of c-myc (p=0.038) related to poor survival whereas increased positivity for p53 predicted better survival (p=0.013). CONCLUSIONS: These data indicate that laser cytometric technology can be used to obtain quantitative data on oncoproteins expression and cell proliferation rates in clinical samples of malignant melanoma.

Cell Proliferation↗

PubMed2005

South-East Scotland trabeculectomy survey.

AIM: Assessment of trabeculectomy in South-East Scotland (SESTS) with comparison to National Survey of Trabeculectomy (NST) and outcomes of consultant and trainee surgery. METHOD: A retrospective study of 304 consecutive, primary trabeculectomies, in two Scottish centres (Edinburgh and Dunfermline) with two glaucoma specialists and higher surgical trainees, was performed. The study group had primary open angle glaucoma (65.5%), pseudoexfoliation (6.9%), normal tension glaucoma (7.6%), pigment dispersion syndrome (1.6%), and other complicated glaucoma (18.4%). All patients underwent trabeculectomy by the glaucoma specialist (57.6%) and higher surgical trainee (42.4%) with close scrubbed supervision. RESULTS: Compared to the NST, the waiting time for surgery (<3 months) was significantly less in the SESTS (P<0.001). There was also significantly more use of intraoperative antimetabolites (P<0.01), bleb intervention (P<0.001), and a higher rate of early complications (P<0.025). There was no significant difference in outcome at intraocular pressure (IOP)<2/3 listing IOP (qualified and unqualified) between the SESTS and the NST. Significantly, more patients achieved an unqualified success of IOP<21 mmHg (P<0.01) and an unqualified success of IOP<16 mmHg in the SESTS than the NST (P<0.05). At 1 year post surgery, visual loss of greater than one Snellen line was more common in the NST (P<0.01) as was the use of anti-glaucoma medication (P<0.001). Trainee cases returned to theatre more frequently (P<0.025) and merited more bleb intervention (P<0.01) than consultant cases, but the long-term outcome was similar. CONCLUSION: Our study highlights significant changes in the practice and outcome of trabeculectomy compared to the national survey conducted a decade ago.

Aged↗

PubMed2005

Histological evaluation of Permacol as a subcutaneous implant over a 20-week period in the rat model.

This study assessed the suitability of Permacol (a porcine derived, isocyanate cross linked collagen based biomaterial) as an alternative to autologous tissue in soft tissue reconstruction. The Sprague-Dawley rat was used as a model for subcutaneous implantation over a 20 week period and comparison made with two other porcine biomaterials (small intestinal submucosa and glycerol treated-ethylene oxide sterilised porcine dermis). Implants were scored histometrically on the degree of acute inflammation, chronic inflammation, fibrosis and stromal response. The vascularity and percentage composition of collagen within Permacol were assessed by stereology and seescan image analysis, respectively. In general terms, Permacol was well tolerated as a subcutaneous implant, with only a minor chronic inflammatory response remaining after a 20 week period of implantation. There was evidence of collagen degradation during this period and vascular ingrowth into Permacol was limited. Permacol has the potential for a broad range of applications in plastic surgery, but may benefit from modification to promote a more rapid degree of vascularisation.

Acute Disease↗

PubMed2005

Visual impairment in elderly patients with hip fracture: causes and associations.

AIMS: To evaluate the current visual status and ophthalmic history of a sample of elderly patients with fractured neck of femur and to study the relationship between visual status and demographic factors. METHODS: A four-centre study of all patients admitted to hospital with fractured neck of femur. The setting was two district (Ayr, Dunfermline) and two teaching (Glasgow, Dundee) hospitals in Scotland. The study examined 537 patients aged 65 years and over admitted with acute fractured neck of femur to hospital. RESULTS: Bilateral visual impairment (binocular visual acuity worse than 6/12) was found in 239 of 518 patients (46%). Of this group, the principal causes for visual deficit were untreated cataract (49%), macular degeneration (21%), uncorrected refractive error (17%), and glaucoma (3%). The visually impaired group were more likely to have symptomatic visual complaints (58 vs 26%), however, were less likely to be under optometric care (71 vs 85%). A higher proportion of the group with visual impairment lived in areas of social deprivation (40 vs 26%). CONCLUSIONS: Patients with fractured neck of femur represent a frail elderly group that have poorer vision than that documented in any other elderly population. The visual defect was potentially remediable in the majority of cases but this group of individuals are not generally in touch with the ophthalmic services. Social deprivation appears to be associated with this groups' inability to access ophthalmic care.

Aged↗

PubMed2005

Glaucoma electronic patient record--design, experience and study of high-risk patients.

AIM: To set-up a glaucoma electronic patient record (GEPR) and study referral details to a new glaucoma service, concentrating on high-risk patients. METHOD: A GEPR was designed using the pre-existing hospital information technology (IT) infrastructure. Referral details of all new patients to the glaucoma service were completely electronically entered and analysed. RESULTS: A GEPR was successfully established. A total of 402 referrals were studied. In all, 43% (40) of high-risk clinic patients (IOP>29 mmHg, or C/D ratio >0.8 or moderate to advanced visual field defects) had to wait longer than 8 weeks from GP referral to be seen at the glaucoma service. Of these, nine patients lost more than one line of Snellen's visual acuity attributable to glaucoma. The optometrist failed to document IOP in 17%, fundoscopy in 30%, and visual fields in 45% of all referrals. CONCLUSIONS: A GEPR can be introduced in an NHS setting without disruption of clinical care and ophthalmic training, and facilitates detailed, accurate and rapid audit. Study of high-risk glaucoma referrals showed inadequate optometric referral details and poor prioritisation of urgent cases. This information is being utilised with the cooperation of local optometrists to refine the pattern of glaucoma referrals.

Glaucoma↗

PubMed2005

Optometric and ophthalmic contact in elderly hip fracture patients with visual impairment.

AIM: To describe previous contact with optometry and ophthalmic services in a group of elderly patients with and without visual impairment (VI) who had fallen and sustained a fractured neck of femur. METHOD: A cross sectional study of 537 patients aged 65 and over who had undergone hip fracture surgery in four Scottish centres (Glasgow, Ayr, Dundee and Fife). All patients had an in-depth optometric history, ophthalmic history and examination. RESULTS: Three hundred and ninety-three (79%) patients reported optometric contact in the 3 years preceding surgery and 107 (21%) patients had not seen an optometrist for more than 3 years. In the latter group, 64 had VI, which was due to uncorrected refractive error in 17 (27%) and untreated cataract in 20 (31%). VI (best binocular visual acuity of 6/18 or less) was found in 239 (46%) patients. A past ophthalmic history was present in 257 (50%) patients. Only 39 (16%) patients with VI were under ophthalmic care at the time of the study. CONCLUSIONS: There was significantly poor optometric and ophthalmic contact in patients who had VI and had fallen and sustained hip fracture. A proportion of the VI (66%) was due to uncorrected refractive error and untreated cataract. Public health providers should be made aware of the fact that current optometric and ophthalmic care pathways are not accessed by this group of elderly patients with VI and at risk of falling.

Accidental Falls↗

PubMed2005

Metastatic carcinoma presenting as cranial nerve palsy.

Adult onset, multiple oculo-motor nerve palsies are usually due to neoplasia and trauma. We report two cases whose initial presenting sign was oculo-motor cranial nerve palsy and were later found to have metastatic carcinoma.

Adult↗

PubMed2004

Healthy and pre-eclamptic placental basal plate lining cells: quantitative comparisons based on confocal laser scanning microscopy.

Immunocytochemical confocal laser scanning microscope images of the monolayer of cells lining the intervillus space at the basal plate of term placentae were analysed using stereology. Immunoreactively-distinct regions of this mosaic layer were measured. In basal plate from healthy pregnancies, trophoblast epithelium occupied 18.91% of the surface area and endothelium 60.81%. In pre-eclampsia the equivalent areas were 15.57% and 67.63%. Acellular fibrinoid covers the remaining area and this component decreases in area in pre-eclampsia. The statistically significant increase in the cellular endothelial compartment may be relevant to the hypertensive pathology of pre-eclampsia as endothelial signalling plays a major role in regulation of blood pressure.

Endothelial Cells↗

PubMed2004

Confocal laser scanning microscope study of cytokeratin immunofluorescence differences between villous and extravillous trophoblast: cytokeratin downregulation in pre-eclampsia.

Pre-eclampsia is a disease characterized by failures in interstitial implantation. One product of the implantation process is the basal plate; a structure whose complexity makes it hard to fully appreciate the pathological changes in significant diseases of pregnancy. This article describes our use of CLSM immunofluorescence to examine the cytokeratin composition of the cells of trophoblastic origin in the term placental basal plate. Large differences in the content of the structural polymeric protein were compared using analysis of digital images. We show that greater pancytokeratin immunofluorescence is observed in extravillous cytotrophoblast cells as compared with villous trophoblast. There is a >30-fold difference in the mean area percent of the most intensely immunofluorescent pixels in the tissue containing these cells. This is a very high, statistically significant difference as defined by the Wilcoxon Signed Ranks Test Asym. Sig. (two-tailed): P < 0.001. The most invasive population of cells of the trophoblast lineage (the extravillous trophoblast) exhibits a significant reduction in cytokeratin immunofluorescence when comparisons of healthy and pre-eclamptic pregnancies are made. This ratio was 2.4:1. It was tested using the Mann-Whitney U-test. From healthy to pre-eclamptic the reduction was from mean rank 83.42((healthy)) to 51.13((pre-eclamptic)). The difference was very highly statistically significant (n = 53 + 75 = 128; U = 984.500; Z = -4.852; P < 0.001). There was also less cytokeratin-related immunofluorescence in villous trophoblast when healthy villi were compared with pre-eclamptic villi. The observed alterations in trophoblastic cytoskeletal components are expected to damage the anchorage and motility of cells. The extravillous trophoblast is known to be necessary for implantation. This leads to a cellular hypothesis of the failure of implantation resulting in reduced depth of uterine invasion and failure to adapt the spiral arterioles for low-pressure perfusion of the intervillus space, two well-known features of pre-eclampsia. The reduction in cytokeratin-related immunofluorescence in the villus trophoblast seen on comparing healthy term placentae with those from pre-eclamptics implies that the trophoblast is a weaker epithelial layer in the hypertensive pregnancy. This could account for the rise in deported trophoblast associated with pre-eclampsia. Deported trophoblast has been invoked as the systemic messenger that leads to generalized maternal hypertension seen in this condition.

Cell Differentiation↗

PubMed2004

Use of an early-detection strategy to improve disease control in melanoma patients.

In order to assess whether early detection might lead to improvement in disease control for patients with melanoma, a rapid access pigmented lesion clinic (PLC) was set up at Mount Vernon Hospital, UK in 1993. Previously we have shown that thinner melanomas were detected via the PLC compared with those presenting prior to its establishment and with those referred via existing routes of referral. The aim of this study was to investigate whether both rates of disease recurrence and disease-free interval were improved via a rapid access PLC. A retrospective case notes audit was performed on three patient groups: those diagnosed with melanoma 1991-1992, those diagnosed via the PLC (1993-1996) and those diagnosed with melanoma through existing routes of referral after establishment of the PLC (1993-1996). There was a significantly improved disease-free interval for patients with regional recurrences diagnosed via the pigmented lesion clinic (PLC) when compared with pre-PLC, non-PLC groups (chi2=13.8487, p=0.0002; chi2=17.0164, p<0.0001, respectively), and when compared with all melanoma patients diagnosed after the establishment of the PLC, irrespective of route of referral (chi2=5.2773, p=0.0216). Local recurrences developed later in patients in the PLC group compared with the pre-PLC group (chi2=6.4883, p=0.0109), and the non-PLC group (chi2=18.49, p<0.0001). In addition there was a reduction in the proportion of regional and local recurrences in the PLC group when compared with the pre-PLC group (chi2=13.92, P<0.001; chi2=2.85, P=0.09 respectively) and non-PLC group (chi2=17.15, P<0.001; chi2=7.73, P=0.005, respectively). These results support the use of rapid access PLCs as a means of improving disease control for melanoma patients.

Ambulatory Care Facilities↗

PubMed2004

Evaluation of a porcine origin acellular dermal matrix and small intestinal submucosa as dermal replacements in preventing secondary skin graft contraction.

The degree to which a split thickness skin graft (STSG) contracts after application to its recipient bed is related in part to the proportion of the dermis harvested from the donor site. Harvesting thicker skin grafts may produce better cosmetic results in the recipient bed but result in increased donor site morbidity. The combination of an autologous ultra thin split thickness graft with an underlying non-autologous dermal component may reduce secondary skin graft contraction without further increasing donor site morbidity. This study was aimed at assessing the suitability of two porcine derived biomaterials (Permacol and small intestinal submucosa, SIS) for use in combination with skin grafts in a Sprague-Dawley rat model. Full thickness wounds (1 cm(2)) were created in Sprague-Dawley rats and grafted with skin in combination with Permacol or SIS either as a one-stage operation or following a 2-week-period of vascularisation of these dermal matrices before a second stage operation to cover with skin. Skin graft viability and wound area were assessed at weekly intervals until 4 weeks after graft application. Both Permacol and SIS were able to support an overlying skin graft but had no beneficial effect on skin graft contraction in this model compared to skin grafts alone.

Animals↗

PubMed2004

The diamond CO2 laser as a method of improving the vascularisation of a permanent collagen implant.

For a biomaterial to be considered as anything other than a simple filler material it must allow a certain degree of ingrowth from the surrounding host tissues. Permacol is a novel porcine derived biomaterial that is isocynate crosslinked to prevent its degradation in vivo, but while it appears to be biocompatible in terms of its histological tissue response, our early studies demonstrate only a limited degree of fibrovascular ingrowth. The aim of this study was to assess the effectiveness of both laser perforations and topically applied VEGF as methods of encouraging fibrovascular ingrowth. Treatment of Permacol with the diamond CO(2) laser significantly increased the porosity of the material as assessed by seescan image analysis. Fibrovascular ingrowth as assessed in the Sprague-dawley rat model was found to be limited to the pores themselves and not the surrounding native matrix. Pre-soaking of laser treated Permacol in vascular endothelial growth factor (VEGF) did not further increase fibrovascular ingrowth. Increasing the porosity of Permacol may allow its use as a dermal replacement in the support of an overlying skin graft or keratinocyte sheet; however using the laser may not be the optimal method of achieving this aim.

Animals↗

PubMed2004

Blindness from acute angle-closure glaucoma after blepharoplasty.

An elderly man had acute angle-closure glaucoma soon after undergoing bilateral lower eyelid blepharoplasty that resulted in complete loss of vision in one eye. Glaucoma is a rare complication of blepharoplasty surgery; only two previous cases have been reported to our knowledge. Risk factors for the development of glaucoma in the setting of blepharoplasty are discussed.

Acute Disease↗

PubMed2004

Ten years of glaucoma blindness in Fife 1990-99 and the implications for ophthalmology, optometry and rehabilitation services.

The aim of this study was to determine the characteristics of the patients in Fife who were registered as blind with a main diagnosis of glaucoma between 1990 and 1999. The case notes of 87 people were studied. The average age at registration was 78 years (S.D. = 14). By the time of first referral to hospital, more than half were already aware of visual loss. Forty-five per cent of referrals had no optometry input. Compliance with treatment was poor in at least 26% of patients. Only 44% had glaucoma surgery. There were significant findings with regard to mental health, particularly dementia, which was eventually present in 24%. At least one-third of patients had a hearing impairment. One-third of those registered as blind could have been registered earlier. However, staff from the local provider of rehabilitation and social work services for the blind were shown to have provided prompt and helpful support to 95% of those registered. Consideration should be given to the way in which elderly patients with advanced glaucoma are managed, with awareness of mental health and hearing problems and emphasis on early referral to rehabilitation services.

Aged↗

PubMed2003

Prefabricated skin flaps in a rat model based on a dermal replacement matrix Permacol.

The reconstruction of three-dimensional structures is one of the most challenging problems in plastic surgery. While shaped frameworks incorporated within soft tissue envelopes often lose their fine detail, the integration of a blood supply to a stable biomaterial scaffold allows skin graft cover and emphasis of fine detail. The aim of this study was to evaluate whether a porcine derived isocyanate crosslinked collagen tissue matrix (Permacol) could be vascularised from an isolated vascular pedicle and subsequently sustain an overlying skin graft as a pedicled prefabricated flap. A vascular induction technique was employed using the epigastric pedicles in Sprague-Dawley rats to vascularise 2 x 2 cm(2) pieces of Permacol of standard 0.75 and 1.5 mm thickness Permacol and laser treated Permacol of 0.4 and 0.75 mm thickness. Flaps were able to support overlying skin grafts as early as 2 weeks following vessel implantation and laser treated Permacol had an increased vascularity compared to standard Permacol with no evidence of degradation. The study showed that Permacol could be a useful matrix for use in tissue engineered flaps.

Animals↗

PubMed2002

Plastic surgery research in the UK.

There is no single source of information on plastic surgery research in the UK. We sought to compile such information from a survey of trainees and consultants, and present an overview of the research activity, the number and designation of those engaged in research, sources of funds, principal areas of investigation and the perceived future for research.

Humans↗