Biomedical subjects

L A Ficker

Publications and source records attributed to L A Ficker.

At least 37 records · Page 2Linked to original sources

PubMed1993

A review of 72 consecutive cases of Acanthamoeba keratitis, 1984-1992.

A review of consecutive cases of Acanthamoeba keratitis presenting since 1984 was undertaken in order to assess prognostic factors, the success of culture procedures and the outcome of medical and surgical management, with reference to current clinical practice. Seventy-two consecutive cases (77 eyes) of Acanthamoeba keratitis have been managed. Sixty-four patients were contact lens wearers, 28 of these wearing disposable lenses. Superficial corneal involvement and perineural infiltrates were common in those diagnosed less than a month after first symptoms, designated 'early' presentation. Ring infiltrates and ulceration with stromal lysis characterised those presenting at 1-2 months ('intermediate') or after 2 months ('late'); these groups also progressed more frequently to hypopyon, scleritis, glaucoma and cataract formation. Positive corneal cultures were obtained in 10 of 14 (71%) intermediate and 17 of 23 (74%) late cases; early cases underwent epithelial biopsy but formal trephine biopsy was not usually justified (1 of 35 cases) and only 19 of 35 (54%) were tissue-positive. Microbial co-isolates were obtained from 20 corneas. Thirty-four penetrating keratoplasties were performed in 23 eyes, 21 whilst inflamed and 13 when quiet. Of 13 failures in inflamed eyes, 9 were due to recurrence of Acanthamoeba infection. Medical cure is known to have been achieved in 64 of 73 (88%) eyes, 4 of the original 77 having been lost to follow-up abroad. Fifty-eight of 73 eyes (79%) achieved a final visual acuity of 6/12, and of the culture-positive cases, 32 of 46 (70%) achieved 6/12.(ABSTRACT TRUNCATED AT 250 WORDS)

Acanthamoeba↗

PubMed1992

Risk factors for the development of postkeratoplasty glaucoma.

From a database of 1,122 penetrating keratoplasties performed under the care of the surgeons of the Corneal Clinic, Moorfields Eye Hospital (London, U.K.), 153 (14%) were identified as being complicated by postkeratoplasty glaucoma. The relative risk for its development varied with the indication for keratoplasty. Keratoconus had the lowest incidence along with some dystrophies, such as macular or granular dystrophy, and these were taken as the baseline for comparison. Anterior chamber dysgenesis syndromes had the highest risk among the indications for keratoplasty. Combined cataract or lens implant surgery was also found to be a risk factor, with anterior vitrectomy, anterior segment revision, and anterior chamber lens implant removal representing a greater risk than extracapsular extraction and posterior chamber lens implantation. Postkeratoplasty glaucoma was also strongly associated with peripheral anterior synechiae formation seen after keratoplasty.

Cataract Extraction↗

PubMed1992

Coexistent corneal disease and glaucoma managed by either drainage surgery and subsequent keratoplasty or combined drainage surgery and penetrating keratoplasty.

The results of penetrating keratoplasty following trabeculectomy in 26 eyes where there was coexistent corneal disease and glaucoma are presented. Patients were aged 16-80 years at the time of drainage surgery (mean = 51 years) and there was a mean of 33.5 months between trabeculectomy and keratoplasty. The mean pressure fell from 35.3 mm Hg prior to trabeculectomy to 14.9 mm Hg at the time of keratoplasty and 20 mm Hg 12 months after keratoplasty. There was a 0.45 probability of maintaining normal intraocular pressure with medication at 5 years after keratoplasty; and a similar graft survival probability. The probability of maintaining both a clear graft and a normal pressure was only 0.27 at 5 years. In another 22 eyes combined trabeculectomy and penetrating keratoplasty was performed. Patients' ages ranged from 21-82 years (mean 55) at surgery, and 73% were aphakic. The intraocular pressure dropped from a mean of 28.9 mm Hg preoperatively to 14 mm Hg at 12 months. There was a 5 year probability of 0.7 of maintaining a clear graft but if both a clear graft and normal intraocular pressure are considered then the probability falls to 0.5 at 5 years. The hazard ratio for intraocular pressure control and graft survival between the two groups suggests that combined surgery may offer a better prognosis.

Adolescent↗

PubMed1991

Refractive surgery for graft-induced astigmatism after penetrating keratoplasty for keratoconus.

Of a series of 201 corneal transplants for keratoconus over a 20-year period, 42 grafts (39 eyes of 38 patients) required further surgery because of intolerable astigmatism (range, -3 diopters [D] to -18 D; mean, 8.9 D). Relaxing incisions, compressive resuturing, and augmented relaxing incisions were the techniques used. All procedures resulted in a similar mean reduction in cylinder -3.6 to 5 D, but the outcome with augmented relaxing incisions was less predictable. Six grafts required two or more procedures for a satisfactory outcome. All patients had corrected visual acuity of 20/30 or better after surgery, and 75% had visual acuity of 20/20 or better. The cumulative time until 90% of the grafts had useful vision was 32 months after refractive surgery. Relaxing incisions offer the prospect of more rapid visual rehabilitation than compressive resuturing.

Astigmatism↗

PubMed1991

The role of penetrating keratoplasty in the management of microbial keratitis.

Penetrating keratoplasty was performed as an emergency procedure in 52 eyes which had perforated from acute microbial keratitis and in a further 11 where perforation had not yet occurred. The results are compared with those of keratoplasty in 33 non-infected perforations and 20 eyes where there had been microbial keratitis which had responded to medical therapy leaving a scarred cornea. This latter group had both a better five year survival (90%) compared to all the others (51%), p less than 0.05, and achieved significantly better visual acuities, p less than 0.005.

Graft Survival↗

PubMed1990

Vitreous cefazolin levels after intravenous injection. Effects of inflammation, repeated antibiotic doses, and surgery.

We devised a standardized rabbit model of intraocular inflammation using heat-killed Staphylococcus epidermidis as the inducing organism. We applied this model to study the effects of (1) inflammation, (2) repeated antibiotic doses, and (3) surgical status of the eye on cefazolin levels in the vitreous cavity after intravenous administration. Intravenous cefazolin sodium, 50 mg/kg, was administered every 8 hours for 48 hours. Eyes were harvested for assay of vitreous cavity antibiotic levels at various intervals from 1 to 49 hours. Drug levels were compared in inflamed and noninflamed eyes under both phakic and aphakic/vitrectomized conditions. At 1 hour, levels in phakic specimens were 3.0 mg/L in inflamed eyes vs undetectable in noninflamed eyes (P less than .01), but progressively increased to 10.6 mg/L at 49 hours (P less than .02) in inflamed eyes only. Levels in aphakic/vitrectomized eyes at 1 hour were 6.7 mg/L in inflamed eyes vs 4.2 mg/L in noninflamed eyes (P less than .1), but progressively increased to 24.9 mg/L at 49 hours (P less than .001) in inflamed eyes only. Levels at 49 hours in inflamed phakic and inflamed aphakic/vitrectomized eyes were well above the minimum inhibitory concentrations for organisms termed sensitive to cefazolin. We would conclude, therefore, that repeated doses of intravenous cefazolin may play an important adjunctive role in the treatment of endophthalmitis.

Analysis of Variance↗

PubMed1990

Microbial keratitis after penetrating keratoplasty.

Thirty cases of microbial keratitis after penetrating keratoplasty were reviewed to examine the associated risk factors, the spectrum of pathogens and the prognosis for graft survival and visual outcome. The indications for keratoplasty in this group differed markedly from those for all corneal grafts performed with a much higher incidence of previous microbial keratitis and of herpes simplex keratitis. A positive culture was obtained in 93% of cases and in contrast to microbial keratitis overall, Gram positive organisms predominated particularly streptococcus pneumoniae and staphylococcus aureus. Risk factors identified were loose or broken sutures, graft decompensation and a poor ocular surface environment. There was a poor prognosis for graft survival with only 23% of cases retaining a clear graft. Overall 53% of cases were regrafted.

Adult↗

PubMed1990

The success of penetrating keratoplasty for keratoconus.

We report the results, over a 20 year period up to 1989, of 201 penetrating keratoplasties in 198 eyes of 158 patients. The five year graft survival was 97%. A corrected visual acuity of 6/12 or better was attained by 91%. The mean spherical equivalent refraction on removal of sutures was -2.68 Ds and the mean cylindrical correction was -5.56 Ds. The cumulative time to dispensing final refractive correction was 38 months for 90% of patients. Rejection episodes occurred in 20% of grafts and were associated with loosening of sutures and bilateral grafts. Atopic patients (28%) were not at greater risk from rejection. Graft refractive surgery was undertaken in 18% and, of these, 55% achieved 6/12 vision or better with an refractive correction which could be dispensed and tolerated within 6 months.

Adolescent↗

PubMed1990

Intraocular surgery following penetrating keratoplasty: the risks and advantages.

Graft survival has been evaluated for patients who underwent subsequent intraocular surgery (extra-capsular cataract surgery or trabeculectomy) between 1983 and 1989. The patients were different from the majority of keratoplasty patients as evidenced by the indications for keratoplasty; corneal perforation was the indication in 24% of cases. Perforated and inflamed eyes were treated aggressively at the time of the acute event, including emergency keratoplasty and intensive topical steroids. Visco-elastic fluids were routinely used during secondary surgery and topical steroids were administered intensively post-operatively. The incidence of post-operative graft rejection was low (less than 14%). Rejection episodes were diagnosed early, prior to the appearance of a Khodadoust line, and were treated aggressively with intensive topical steroids. Glaucoma which was not controlled by topical therapy was surgically managed by trabeculectomy in the first instance. If this failed, tube drainage was performed and long-term topical steroids were administered. The only risk factor identified was uncontrolled glaucoma, P = 0.1. The probability of graft survival (at five years) was 0.83 after cataract surgery and 0.62 after trabeculectomy, but wide confidence limits indicate the difference is not significant.

Cataract↗

PubMed1990

Recurrent macular corneal dystrophy following penetrating keratoplasty.

The recurrence of macular corneal dystrophy within a corneal graft has been described in a number of case reports. In this study, we reviewed 41 transplants in 31 eyes of 16 patients undergoing keratoplasty for macular corneal dystrophy confirmed by histopathological examination. The follow-up time ranged between 25 and 408 months from initial diagnosis. Six eyes of four patients had repeat keratoplasty because of clinical recurrence and visual impairment. Pathological confirmation was available in five of the six eyes. Peripheral clinical recurrence was observed in two more eyes. The size of the graft used was inversely related to the recurrence.

Adult↗

PubMed1989

The changing management and improved prognosis for corneal grafting in herpes simplex keratitis.

Graft survival in a previously reported cohort of patients recruited between 1967 and 1978 (10.6 years' mean follow-up) was reviewed and compared with that for a cohort recruited between 1979 and 1987 (3.8 years' mean follow-up). This allowed analysis of improved graft survival due to changes in management, introduced after critical review of the first group in 1978. The salient changes included transition from intracapsular to extracapsular cataract surgery (P = 0.001) and treatment of rejection episodes with antiviral prophylaxis. Extracapsular cataract surgery improved graft survival (P = 0.07) benefiting inflamed eyes which more frequently required concomitant surgery (P = 0.005). Survival of rejection episodes was improved by antiviral prophylaxis (P = 0.02), and the incidence of recurrent keratitis was reduced (P = 0.0005). The complete and prompt removal of loose sutures improved graft survival (P = 0.025). Long-term survival of first grafts was 70%, and management changes improved overall survival (P = 0.036) despite an increased number of eyes (P = 0.05) grafted when inflamed.

Cataract Extraction↗

PubMed1989

The management of post-keratoplasty glaucoma by trabeculectomy.

The results of 35 consecutive trabeculectomies in eyes developing medically uncontrollable glaucoma following penetrating keratoplasty are presented, with a mean follow-up of 3 years from the time of drainage surgery. Five eyes remained phakic until trabeculectomy was performed. Additional medical therapy was necessary to control the intraocular pressure in 32 eyes, which therefore were considered to have failed to be controlled by trabeculectomy and 90% of these failed within 6 months of filtration surgery. Despite additional medical therapy, in 17 eyes, further drainage surgery was required and 90% of this surgery took place within the first 14 months. Adverse prognostic factors were multiple grafts and synechiae closure of the drainage angle.

Acetazolamide↗

PubMed1989

Large corneal grafts can be successful.

Seventeen grafts of 10 mm in diameter or larger have been performed on 16 eyes of 15 patients. The major indications for surgery were infections or perforations or both. Follow-up has ranged from 8-54 months (mean 26.4). The 4 year survival probability was 0.64. Although the procedure was successful in saving all but one eye and restored useful vision in the majority, complications including cataract, glaucoma, graft rejection episodes and infections were encountered. The management of these complications is described. At final review, 13 eyes had clear grafts including those in whom regraft had been performed. These results have only been achieved by close co-operation between patients and the medical team responsible for their care.

Adolescent↗

PubMed1988

Longterm prognosis for corneal grafting in herpes simplex keratitis.

A previously reported cohort of patients was reviewed after mean follow-up of 10.9 years. The overall probability of survival was 45%, but first grafts had a greater probability of survival than second (P = 0.12) or further (P = 0.19) grafts. Preoperative active keratitis adversely affected survival (P = 0.123). The major cause of failure was graft rejection. Regrafts were more likely to fail from rejection episodes (P = 0.0005). Antiviral prophylaxis improved the outcome for rejection (P = 0.005) and reduced the incidence of HSK recurrence complicating rejection. Suppurative keratitis occurred in 12.4% of grafts as a complication of epitheliopathy including HSK recurrence. The outcome in these cases was particularly poor. Loose continuous graft sutures resulted in graft failure in 10.6% of grafts which may be improved by using interrupted suturing. Our results suggest the longterm prognosis for grafting in herpes simplex keratitis are not as good as may have been predicted from previous analyses.

Cornea↗

PubMed1988

Role of vitrectomy in Staphylococcus epidermidis endophthalmitis.

Seventeen patients with endophthalmitis due to coagulase-negative staphylococcus were treated over a nine-year period with vitrectomy, intraocular antibiotics, and systemic steroids and antibiotics. Fifteen patients presented with moderate to severe disease and visual acuities from counting fingers to light perception, while two had acuities of 20/60 and 20/200. A final visual outcome of 20/70 or better was achieved in 13 of 17 eyes (76%). Only one eye lost perception of light secondary to retinal detachment. Therapy including vitrectomy is an effective means of controlling moderate to severe coagulase-negative staphylococcal endophthalmitis and restoring vision.

Anti-Bacterial Agents↗

PubMed1987

Retinal detachment following Nd:YAG posterior capsulotomy.

Five hundred and eighty-two patients who underwent Nd:YAG laser posterior capsulotomy at Moorfields Eye Hospital were reviewed retrospectively. Twelve patients (2 per cent), nine of whom were previously myopic, subsequently developed rhegmatogenous retinal detachment. Comparison with other studies suggests there is no greater risk of retinal detachment associated with Nd:YAG laser capsulotomy than with surgical discission. The relevance of the damage mechanisms of Nd:YAG lasers are discussed.

Eye Diseases↗

PubMed1986

Xenon-arc endophotocoagulation during vitrectomy for diabetic vitreous haemorrhage.

The value of scatter xenon-arc endophotocoagulation in stabilising eyes with respect to post-operative rubeosis iridis and vitreous haemorrhage is demonstrated in a consecutive series of 100 vitrectomies undertaken for diabetic vitreous haemorrhage. Seventy eyes ultimately achieved 6/36 or better vision. Endophotocoagulation of untreated ischaemic retina is recommended in eyes undergoing vitrectomy for diabetic vitreous haemorrhage.

Diabetes Complications↗

PubMed1986

Management of ipsilateral ptosis with hypotropia.

Thirty-one patients presented for surgical correction of unilateral hypotropia of the globe and blepharoptosis. The hypotropia and pseudoptosis were corrected by Knapp procedures. The Bell's phenomenon was thereby improved, allowing safe correction of the true ptosis, generally by an anterior levator resection whose magnitude depended on measured levator function.

Blepharoptosis↗