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J N McGalliard

Publications and source records attributed to J N McGalliard.

At least 19 recordsLinked to original sources
PubMed2005

A pilot study on the use of a perfluorohexyloctane/silicone oil solution as a heavier than water internal tamponade agent.

AIMS: To report a prospective two centred non-comparative interventional pilot study of a solution of perfluorohexyloctane and silicone oil (Densiron-68) as a heavier than water internal tamponade. METHODS: 42 consecutive patients were recruited. The indications include proliferative vitreoretinopathy, retinal detachments arising from inferior retinal breaks, and inability to posture. RESULTS: The success rate with one operation using Densiron was 81% and with further surgery 93%. At the end of the study all tamponade agents were removed in 90% of patients. Visual acuity improved from mean logMAR of 1.41 (SD 0.64) to 0.94 (SD 0.57), p = 0.001. There was little evidence of dispersion and excessive inflammation. CONCLUSION: This new tamponade agent is being compared to conventional silicone oil in a prospective international randomised trial.

Adult↗
PubMed2000

The role of nurse practitioners in a primary care eye clinic.

This paper reports on a study conducted to audit the practice of nurse practitioners in a primary care eye clinic at St Paul's Eye Unit at the Royal Liverpool University Hospital, UK. The clinic deals with ophthalmic accidents and emergencies and routine referral patients from general practitioners. This was a prospective study of the case notes of 250 consecutive patients who attended the clinic without prior appointment. The study was completed in 1 week.

Eye Diseases↗
PubMed1999

Trends in vitreoretinal surgery at a tertiary referral centre: 1987 to 1996.

AIM: To identify trends in vitreoretinal surgery at a tertiary referral centre from 1987 to 1996. METHODS: A retrospective study of patients who had undergone vitreoretinal surgery at St Paul's Eye Unit over two 6 month periods in 1987 and 1996. Preoperative ocular status, surgery details, and outcome were collected. chi 2 and Mann-Whitney U tests were used to analyse the data. RESULTS: The two periods under study were July to December 1987 and January to June 1996. 110 operations performed during 1987 (96 patients) and 330 operations during 1996 (289 patients) were analysed. There was a fourfold rise in the number of tertiary referrals and a seven-fold rise in the number of operations performed for conditions other than rhegmatogenous retinal detachment (RRD). Increasing indications for surgery included diabetic eye disease, macular hole, dropped nucleus, endophthalmitis, and subretinal neovascular membrane. There was a rise in the proportion of patients with RRD following cataract surgery (from 19.5% to 29.5%). For both primary repair and reoperation, vitrectomy with internal tamponade was more commonly used in 1996. The anatomical success rate for primary repair changed from 76.6% to 84.7% after one operation and from 89.1% to 94.3% following additional surgery. CONCLUSIONS: This study points to a trend towards subspecialisation and tertiary referral in vitreoretinal surgery. Vitrectomy techniques are more commonly used for the primary repair of RRD and are applied to a wider spectrum of diseases.

Humans↗
PubMed1998

Intravitreal penetration of teicoplanin.

Teicoplanin is a glycopeptide antibiotic, similar to vancomycin, but safer and better tolerated. The purpose of this study was to evaluate the penetration of teicoplanin into the vitreous when administered topically and intravenously. Twenty-five patients undergoing routine vitrectomy were recruited. Twenty were given intravenous teicoplanin: five 1 h pre-operatively, five 12 h pre-operatively, five 24 h pre-operatively and five 24 h as well as 48 h pre-operatively. Five received teicoplanin drops half-hourly for the 6 h immediately preceding vitrectomy. Undiluted vitreous specimens were obtained at the beginning of each vitrectomy procedure. Teicoplanin levels were measured using a biological assay with Staphylococcus aureus as the indicator organism. Teicoplanin activity was detected in 8 of the 20 specimens from those patients receiving the intravenous antibiotic. Teicoplanin did not penetrate readily into the vitreous cavities in these eyes despite the blood-ocular barrier being compromised in some patients, although there was evidence of accumulation with time. No activity was detected in the vitreous of those patients who received topical teicoplanin.

Adolescent↗
PubMed1998

Local anaesthesia for vitreoretinal surgery: a case-control study of 200 cases.

PURPOSE: In the United Kingdom the majority of vitreoretinal (VR) surgery is performed under general anaesthesia (GA). The aim of this study was to demonstrate the scope of local anaesthesia (LA) for VR surgery, to measure the acceptance of LA to patients and surgeons and to compare the surgical outcomes, complication rates and duration of the surgical procedures under LA and GA. METHODS: A case-control study was undertaken to compare 100 cases performed under LA with 100 matched cases performed under GA. The matching of cases was based on multiple criteria such as configuration and complexity of retinal detachment, the involvement of the macula, the number and site of retinal tears, presence and severity of proliferative vitreoretinopathy, experience of the surgeon and the type of the surgical procedure. A clinical audit was also carried out on 65 successive patients using a questionnaire to determine the acceptability of LA to patients and surgeons. RESULTS: Anatomical and visual success rates, and intra-operative and post-operative complications, were similar in cases carried out under LA and GA. The mean duration of the surgery (excluding anaesthetic time) was significantly shorter for LA than GA procedures (p < 0.001). The acceptance for LA was high for both patients and the operating surgeons. CONCLUSIONS: We found that VR surgery can be safely and efficiently performed under LA. Adoption of LA has increased our throughput.

Anesthesia, General↗
PubMed1997

Removal of lens fragments from the vitreous cavity.

Between March 1993 and September 1994 we treated 25 cases of lenses in the vitreous cavity. Nineteen of the 25 were the result of dislocation during phacoemulsification. During this time, we adopted a single surgical algorithm involving vitrectomy, heavy liquids and ultrasound fragmentation. The aims of this retrospective study were to test the validity of our surgical algorithm and to report on outcomes and complications. The indications for vitreous surgery were raised intraocular pressure, uveitis and poor vision. Vitreous surgery was carried out at a mean of 29 days following phacoemulsification. Six patients required heavy liquids and 5 needed ultrasound fragmentation. Vitreous surgery undertaken less than 17 days after phacoemulsification had an increased likelihood of requiring heavy liquids and/or fragmentation (p < 0.02). The greatest threat to a favourable visual outcome was retinal detachment, which was significantly associated with fragmentation and use of heavy liquids (p < 0.02). The presence of an intraocular lens (IOL) reduced the surgical options for removal of the lens fragments, and IOL should not be inserted where lens matter dislocates. The study suggests that we should avoid fragmentation and, provided the intraocular pressure and uveitis can be controlled, that vitreous surgery should be deferred for 2-3 weeks following phacoemulsification.

Adult↗
PubMed1995

Prevalence of low vision in elderly patients admitted to an acute geriatric unit in Liverpool: elderly people who fall are more likely to have low vision.

The prevalence of visual impairment among elderly patients admitted to hospital is unknown. This group of patients may be particularly at risk from poor vision which could jeopardise their independence. A prospective study of visual imapairment and its aetiology in acute geriatric admissions assessed after the acute illness had settled was performed. Subjects were all patients aged 65 years or over, excluding those chronically confused, admitted to the Department of Geriatric Medicine at the Royal Liverpool University Hospital with an acute medical illness. After the acute illness had settled visual impairment, as defined by the American criteria (best acuity 6/18), was assessed on the ward with a Snellen chart read at 6 m using binocular vision and current glasses. Those patients identified with impaired vision on initial screening were formally assessed in the ophthalmology department to identify the cause. 200 patients were examined. 101 patients (50.5%) had impaired vision. In these patients, correctable refractive errors were present in 40%, cataract in 37% and senile macular degeneration in 14%. Of the 101 patients with impaired vision 79% had a reversible cause. Comparing these results with a recent study in the community showed a much higher incidence for patients admitted to hospital. There was a particularly high prevalence in those elderly patients who were admitted with falls (76%, p = 0.0003). In conclusion, elderly patients, especially those presenting with falls, admitted to hospital have a high prevalence of visual impairment. Visual impairment may be compounding or causing falls.(ABSTRACT TRUNCATED AT 250 WORDS)

Accidental Falls↗
PubMed1994

Traumatic retinal angiopathy and seat belts: pathogenesis of whiplash injury.

Three cases of traumatic retinal angiopathy associated with whiplash injury are presented. The pathogenesis of the fundal appearances is discussed. Local microcirculatory disturbances are postulated as the cause of the retinopathy as opposed to the systemic disturbance associated with Purtscher's retinopathy. This condition may be underdiagnosed as there may be few abnormal signs on funduscopy. Fluorescein angiography may be very helpful. The incidence may be increasing as a result of legislation concerning the wearing of seat belts, and the condition has medico-legal significance. Increasing awareness may increase diagnosis.

Accidents, Traffic↗
PubMed1993

Neovascular complications after central retinal vein occlusion.

An 8-year retrospective study of patients suffering a central retinal vein occlusion (CRVO) was undertaken to study secondary new vessel formation and whether pathologies known to predispose to CRVO influenced the occurrence of these neovascular complications and their responsiveness to treatment. Seventy-three patients were studied. Ocular neovascularisation had occurred in 60%. More specifically 39% developed neovascular glaucoma. Panretinal photocoagulation produced regression in only 37% of those with established neovascularisation and was unsuccessful in preventing neovascularisation in five patients treated prophylactically. Patients with pre-existing primary open angle glaucoma (POAG) were statistically more likely to develop ocular neovascularisation (p = 0.02), which was also less responsive to laser therapy (p = 0.02). Adequate prior glaucoma therapy did not protect against this enhanced complication rate. It was concluded that POAG is a significant risk factor for developing ocular neovascularisation after CRVO which will be refractory to laser therapy.

Adult↗
PubMed1992

Effects of timolol ophthalmic solution on the intra-ocular pressure rise induced by suxamethonium and tracheal intubation.

Thirty patients received topical application of either timolol ophthalmic solution 0.25%, or normal saline, 2 h before elective ophthalmic surgery in a double-blind study. The responses to suxamethonium and tracheal intubation were compared by measuring intra-ocular pressure before induction of anaesthesia, 1 min after administration of thiopentone 2-4 mg.kg-1, 1 min after administration of suxamethonium 1 mg.kg-1, and 1, 2.5 and 5 min after tracheal intubation. There was no significant difference between the groups.

Adult↗
PubMed1991

Nitrous oxide and internal tamponade during vitrectomy.

We analysed the nitrous oxide composition of the intraocular gas bubble following vitrectomy and fluid-air exchange in 12 patients. Samples were taken under standardised conditions at 20 minutes after completion of the fluid-air exchange. Analysis was conducted by a Medishield MS2 mass spectrometer. The percentage composition of nitrous oxide in the samples varied between 4 and 21% (mean 9%). This influx of nitrous oxide was associated with an increase of intraocular pressure. Pressure rises of greater than 20 mm Hg were not seen owing to venting of gas through the sclerostomies. An inverse relationship was noted between the extent of retinal detachment preoperatively and the amount of nitrous oxide entering the eye. A possible explanation for this relationship is proposed. The importance of nitrous oxide movement is stressed.

Adolescent↗
PubMed1990

The effect of Nd:YAG iridotomy on intraocular pressure in hypertensive eyes with shallow anterior chambers.

Eighty one eyes of 48 patients with raised IOP and shallow anterior chambers underwent Nd:YAG iridotomy to prevent further angle closure glaucoma and to remove any pupil block that might be contributing to the raised IOP. These eyes were followed for 18-34 months to assess the effect on IOP control. Seventy three eyes of 43 patients were asymptomatic. In eyes with no PAS none responded with drop in IOP but in eyes with well established PAS 69% showed a drop in IOP. By comparison eight eyes of five patients had a history of episodes of subacute angle closure glaucoma. All had PAS present pre-operatively. Iridotomy reduced IOP in 87.5% of the eyes in this group and rendered 100% symptom free. Permanent posterior synechiae between lens and iris were an invariable complication in those eyes that required long-term miotic treatment for IOP control following iridotomy. In asymptomatic eyes with chronic pressure elevation and narrow angles laser iridotomy is unlikely significantly to reduce the IOP. We recommend that in such eyes iridotomy should be reserved for those eyes with established closure of the angle by PAS in which IOP control can be achieved without the use of miotics.

Adult↗
PubMed1990

The Keeler Pulsair air impulse tonometer. Comparison with the Perkins hand-held applanation tonometer for peri-operative measurement of intra-ocular pressure.

The Keeler Pulsair is a noncontact tonometer which can be used by those without specialist ophthalmic training. The instrument was compared, in a series of 30 patients in whom a total of 150 readings were taken, in respect of accuracy, ease and speed of use, and acceptability to patients, with the Perkins hand-held applanation tonometer. There was good correlation between measurements obtained with the two instruments: r = 0.92, (p less than 0.001); the Pulsair was described as easy to use in 87% of subjects, and no patient found the procedure unpleasant. The median times taken for Pulsair measurements were 7 (range 4-14) seconds for a single reading in conscious patients, and 11 (range 4-29) seconds for four readings in anaesthetised patients. These times were significantly quicker than those recorded with the Perkins tonometer which were 83 (range 66-138) seconds and 20 (range 8-45) seconds respectively (p less than 0.001). We conclude that the Pulsair is suitable for use by those who are not ophthalmologists for the rapid measurement of intra-ocular pressure changes during anaesthesia.

Anesthesia↗
PubMed1990

Comparison of the effects of isoflurane and halothane on intraocular pressure.

Intraocular pressure (IOP) was measured in four groups of patients receiving isoflurane or halothane in consecutively increasing or decreasing concentrations (1.0, 2.0 and 3.0 MAC in 70% nitrous oxide). IOP decreased significantly in all groups irrespective of whether the higher or the lower concentration of the volatile agent was used first. There were no further significant changes in IOP whether the concentrations were increased or decreased, suggesting no dose-relation. Maximum reductions in IOP were slightly greater in those receiving the higher concentrations of the volatile agents first (64 and 66% with isoflurane and halothane, respectively) in comparison to those receiving the lower concentrations first (54 and 46%, respectively).

Adult↗
PubMed1989

A study of iris melanoma in Northern Ireland.

A retrospective study of all cases of iris melanoma in Northern Ireland over a 15-year period was undertaken. A total of 18 cases were identified. Of these, nine were histologically proved to be iris melanomas of various types. Within the period of follow-up two patients died from metastatic deposits. In both cases invasion of the anterior face of the ciliary body was present on histological examination. The implications for management are discussed.

Adult↗