Biomedical subjects

T Zeyen

Publications and source records attributed to T Zeyen.

At least 19 recordsLinked to original sources

PubMed2006

Safe trabeculectomy technique: long term outcome.

AIM: To assess the long term outcome of a new trabeculectomy technique. METHODS: Trabeculectomy was performed using a fornix based conjunctival flap, an anterior chamber maintainer, a standardised punch technique, and a combination of adjustable and releasable sutures in 56 eyes of 53 patients. The main outcome measures were the postoperative intraocular pressure (IOP) and the frequency of early postoperative complications. The mean follow up time was 15.7 (range 12-21) months. RESULTS: The mean preoperative and postoperative IOP at 12 months were 21.2 (SD 6) and 12.8 (3.0) mm Hg, respectively. All patients had an IOP of <21 mm Hg, 90.9% had an IOP <18 mm Hg, and 61.4% had an IOP <14 mm Hg. Postoperative complications were infrequent: flat anterior chamber (1.8%), bleb leakage (0%), or hypotony (1.5%) beyond 3 weeks, or choroidal detachment at any time point (8.9%). CONCLUSIONS: This novel trabeculectomy method offers the possibility to tailor the IOP postoperatively with a minimum of postoperative complications and excellent IOP control at the long term follow up.

Adult↗

PubMed2006

Argon versus selective laser trabeculoplasty.

PURPOSE: To compare conventional argon laser trabeculoplasty (ALT) with selective laser trabeculoplasty (SLT) in terms of their efficiency in lowering the intra-ocular pressure. METHODS: In this retrospective study, 56 eyes from 44 patients with primary open angle glaucoma, ocular hypertension, pseudo-exfoliative (PXF) or pigment dispersion glaucoma (PDG) were included. Patients underwent either ALT (n=18) or SLT (n=38). The intraocular pressure (IOP) was measured immediately prior to and 3 to 5 weeks after the theraPY. RESULTS: At 3 to 5 weeks the lOP-reduction was 22.4% after ALT and 15.5% after SLT (p = 0.141). Of note, of the four patients with PDG 2 underwent ALT and 2 SLT. Remarkably, both patients who had had SLT showed a paradoxical rise in lOP after the procedure (+15.5%). When these patients were excluded from the analysis, a similar hypotensive efficacy was found between ALT (-19%) and SLT (-17.9%) (p = 0.836). A small additional study with lower energy levels (< 0.9 mJ) confirmed the paradoxical IOP rise in 6 patients with heavily pigmented angles (2 with PDG and 2 with PXF) (+19.2%). It occurred in the absence of steroid treatment and persisted until 12 weeks after treatment. CONCLUSIONS: The short term efficacy of ALT and SLT was similar. In this study, the patients with PDG who underwent SLT showed a paradoxical rise in IOR This finding may indicate that even lower energies (0.4 to 0.6 mJ) are required when performing SLT in patients with heavily pigmented trabeculae.

Aged↗

PubMed2005

Pachymetry before or after applanation tonometry: does it matter?

We examined prospectively 60 healthy volunteers to evaluate if the accuracy of central corneal thickness (CCT) measurement is influenced by Goldmann applanation tonometry (GAT) and vice versa. The sequence of the examinations in the right eye was CCT--GAT--CCT, in the left eye GAT--CCT--GAT and the measurements were done consecutively. Two tonometry and five pachymetry measurements were averaged each time. Pearson correlation coefficients and Bland-Altman plots were used to assess the correlation between the measurements. In the right eye the mean CCT measurement before and after GAT was 565.22 +/- 32.99 micro and 566.04 +/- 33.50 micro (p = 0.34, r = 0.98) respectively. In the left eye the mean GAT before and after pachymetry was 19.38 +/- 4.71 mmHg and 19.16 +/- 4.32 mmHg (p = 0.43, r = 0.86) respectively. The study suggests that the sequence of the two examinations doesn't matter.

Adult↗

PubMed2005

Needling-revision of failed filtering blebs.

PURPOSE: To investigate the efficacy and safety of needling-revision of failed blebs after trabeculectomy. METHODS: A retrospective chart review of 28 eyes of 28 patients who underwent a trabeculectomy with subsequent needling-revision between January 2002 and December 2003. The mean follow-up was 15 months after the first needling-revision. All interventions were conducted by the same surgeon. Absolute success was defined as an IOP <18 mmHg without medication or as an IOP reduction > 20% without medication if the preoperative IOP was < or = 21 mmHg. Relative success was defined as meeting these criteria with or without medication. RESULTS: The mean interval between trabeculectomy and the first needling-revision was 5 months. Repeated needling-revision (up to 3 times) was performed as clinically necessary. In 90% of the needling-revisions 5-FU was used to prevent postoperative fibrosis. The mean +/- SD IOP before needling-revision and at the last follow-up was respectively 24.7 +/- 6 and 15.7 +/- 3 mmHg (p<0.001) Needling-revision was an absolute success in 39% (11/28) and a relative success in 68% (19/28). Minor complications attributed to needling-revision occurred in 32% including self reabsorbing subconjunctival bleeding (1), filamental (1) and punctate keratitis (1), transient choroidal effusion (3), wound leak (4) and hyphaema (2). Progression of cataract occurred in 1 patient. A serious complication occurred in 1 case (hypotony with persistent macular oedema). CONCLUSIONS: Bleb needling-revision can prevent more invasive intervention in a significant number of patients with failed trabeculectomy blebs. Complications are similar to those seen after trabeculectomy.

Adult↗

PubMed2005

Screening for vascular risk factors in glaucoma: the GVRF study.

PURPOSE: To determine the prevalence of vascular risk factors (VRF) in patients with primary open-angle glaucoma (POAG), normal tension glaucoma (NTG), and ocular hypertension (OH), and to evaluate their influence in the progression of the disease. METHODS: 269 Belgian ophthalmologists were invited to participate in this cross-sectional prevalence study. Using a questionnaire the following parameters were analyzed in patients with POAG, NTG, and OH: age, intraocular pressure, refraction, visual field defect, vertical cup/disc ratio, medical therapy, and vascular risk factors. Progression of visual field was based on subjective analysis of minimum three reliable automated perimetries over a period of minimum three years. RESULTS: 4920 patients were enrolled in the study. 75% had POAG, 8% had NTG, and 17% had OH. The mean age was 67 years (40-99 y.). Fifty-three percent were female. There was a significant difference in the prevalence of no VRF vs. >1 VRF between the patients with OH and the patients with POAG/NTG (p < 0.01). Visual field progression was found in 34% of the patients with POAG and 46% of the patients with NTG. In the group with POAG the presence of at least 2 and at least 3 VRF increased the risk for visual field progression with respectively 16% and 42% compared to patients without VRF (p = respectively 0.03 and 0.002). CONCLUSIONS: The prevalence of VRF is significantly higher in patients with POAG/NTG compared to patients with OH. The presence of VRF might increase the risk for progression of glaucomatous visual field defects.

Adult↗

PubMed2004

Miscalibration and severe complications after diode laser cyclophotocoagulation: two case reports.

Because two similar transscleral cyclophotocoagulation diode lasers with identical power & duration settings induced significantly different postoperative inflammation, we wanted to compare the real output of both lasers. Using a Power/Energy Meter (Fieldmaster) we compared the output of the two lasers (the Iridis [Quantel Medical] and the Iris Medical [OcuLight SLx]) at different energy levels. At a setting of 600, 1000, 1400, 1700, 2000 and 2500 mW, the measured output for the Iridis and Iris Medical diode laser were respectively 685 and 400 mW, 970 and 650 mW, 1470 and 875 mW, 1700 and 1000 mW, and 1990 compared to 1000 mW. On the average the output of the Iridis laser was correct and the output of the Iris Medical laser was 40% lower than the setting. Overtreatment and severe complications occurred with the Iridis laser because the manufacturer recommended using wrong power settings based on the Iris Medical laser, which was undercalibrated. The calibration of cyclophotocoagulation diode lasers should be performed prior to use when changing to a new device and whenever over- or undertreatment is observed.

Aged↗

PubMed2004

Comparison of optical coherence reflectometry and ultrasound central corneal pachymetry.

In 50 eyes of 25 patients we prospectively measured the central corneal thickness (CCT) comparing the OLCR (Optical Low Coherence Reflectometry) pachymeter with the contact ultrasound pachymeter. The OLCR system was mounted on to a Haag-Streit slit lamp. Every single measurement was the result of 5 scans. With the contact ultrasound Sonomed pachymeter we performed 5 separate measurements and calculated the mean. The correlation between the two measurements was excellent (r = 0.99). The mean standard deviation (SD) of the measurements taken with the non-contact OLCR pachymeter was significantly lower than with the contact ultrasound pachymeter, 0.49 microm and 4.71 microm respectively (p < 0.01). The variability of the CCT measurements taken with the non-contact OLCR pachymeter is significantly lower than the variability of the CCT measurements taken with the contact ultrasound pachymetry.

Cornea↗

PubMed2003

The long-term effect of diode laser cyclodestruction on intraocular pressure.

We retrospectively reviewed the first 24 patients (26 eyes) who underwent ab externo diode laser cyclodestruction for refractory glaucoma and who had a follow-up of at least 10 months. We compared the intraocular pressure (IOP) and the number of antiglaucomatous medications used pre- and postoperatively. The mean follow-up period was 28 months (range 10 to 50 months). The mean IOP before and after treatment was respectively 30 +/- 12 mmHg and 22 +/- 12 mmHg (p < 0.05), a mean reduction of 29%. The average number of treatment sessions was 1.5 (range 1 to 5). An IOP < or = 21 mmHg was obtained in 65% of the cases; an IOP < or = 17 mmHg was achieved in 46% of the cases. The mean number of anti-glaucomatous medications used pre- and postoperatively was respectively 2.3 and 1.7 (p < 0.05). Only mild postoperative uveitis was observed; no eye developed phthisis bulbi. The study suggests that diode laser cyclodestruction is a safe procedure that can reduce the IOP in the long term in patients with refractory glaucoma.

Adolescent↗

PubMed2003

Posterior uveitis: an under-recognized adverse effect of pamidronate: 2 case reports.

Ocular adverse effects of pamidronic acid are rare but well documented. Pamidronate, an inhibitor of bone resorption used primarily in the management of tumor-induced hypercalcemia and Paget's disease, is reported to cause conjunctivitis, anterior uveitis, and infrequently episcleritis and scleritis. It is hypothesized that an allergic or immunologic phenomenon caused by drug-indued immune complex formation is at fault. The reason why the uvea is a target organ is unclear. The acute inflammatory response seems unrelated to the dose of the drug, the way of administration, or the activity of Paget's disease or malignancy. We report two cases of pamidronate-induced posterior uveitis, following the WHO Causality Assessment Guide of Suspected Adverse Reactions. Uveitis and scleritis have been reported in association with a variety of topical, intraocular, periocular, and systemic medications. Seven criteria were proposed to establish causality of adverse events by drugs. Only systemically administered biphosphonates meet all seven criteria. Where pamidronate is currently considered as the drug of choice in diverse strategies, the adverse ocular effects should be well known to physicians in order to make rapid diagnosis and stop the drug causing adverse reaction.

Bone Neoplasms↗

PubMed2002

Subconjunctival Loa Loa worm: case report.

A 38-year old Ghanaian suddenly had the sensation of a foreign body in his right eye. Slit-lamp examination revealed a transparent worm underneath the conjunctiva. With topical anesthesia, the complete worm, 3.5 cm long, was removed surgically. A microbiological analysis at the Institute of Tropical Medicine confirmed the diagnosis of Loa Loa. Laboratory tests showed negative blood eosinophilia, positive blood film examination for microfilariae and positive results for filarial serology. The postoperative treatment consisted of progressive doses of di-ethyl-carbamazine (50-->100-->200 mg/d). A subconjunctival Loa Loa worm is rare in Belgium and usually occurs in immigrants or travellers returning from Tropical (Equatorial) West and Central Africa. Our patient visited Nigeria in 1985 and Ivory Coast in 1986. Those regions are highly endemic for Loa Loa.

Adult↗

PubMed2002

Short-term intra-individual variability in heidelberg retina tomograph II.

We determined the short-term intra-individual variability for each parameter of the Heidelberg Retina Tomograph II (HRT II). Therefore we examined prospectively 20 healthy volunteers 3 times within 2 weeks. The variability was expressed as the coefficient of variation for each parameter. The short-term intra-individual variability in normal subjects was < or = 12% in all but 3 parameters. Rim Area was the least variable parameter (2 +/- 1%). Cup Volume had the highest variability (25 +/- 38%).

Adult↗

PubMed2001

Primary graft failure caused by herpes simplex virus type 1.

PURPOSE: To present a cluster of four patients with primary graft failure (PGF) who consecutively underwent a penetrating keratoplasty (PKP) during a period of 17 days in one institution. PKP was performed for reasons unrelated to herpes simplex infection. Herpes simplex virus type 1 (HSV-1) is presented as the possible cause of these PGFs. METHODS: Viral culture of conjunctival swabs and of a bandage contact lens was performed on VERO, MRC-5, and Hep-2 cells. The four patients underwent subsequent regrafting. Polymerase chain reaction (PCR) for HSV-1 was carried out on aqueous humor and on a sample of iris and cornea with primers. Aqueous humor specimens were pretreated by boiling, and a qiagen extraction was performed according to the instructions of the manufacturer on biopsies of iris and cornea. Immunohistopathology was performed with polyclonal antibodies directed against HSV-1 and -2. RESULTS: Culture of a conjunctival swab in three patients and culture of a bandage contact lens in the fourth patient were positive for HSV-1. In three of the four patients, PCR was positive for HSV-1 on aqueous humor and corneal graft tissue. PCR on iris tissue was positive in all patients. In three patients, culture for HSV-1 of aqueous humor and of iris tissue could not be carried out because of insufficient sample. Viral culture of the iris tissue in one patient and of the corneal graft in the four patients were negative. Immunohistopathologic examination was positive for HSV-1 in three cases. CONCLUSION: These case reports strongly support the hypothesis that HSV-1 can be the cause of PGF.

Adult↗

PubMed2001

Reduction in IOP after clear corneal phacoemulsification in normal patients.

A prospective study was performed to evaluate the changes in intraocular pressure (IOP) after clear corneal phacoemulsification in normal patients. The mean preoperative IOP of 30 patients was compared with the IOP at 1, 2, 3, and 5 months postoperatively. Lens extraction was associated with a reduction of IOP of 3.36 mmHg (SD +/- 2.33--p = 0.005) after 5 months.

Aged↗

PubMed2001

Improvement of acquired pendular nystagmus by gabapentin: case report.

Acquired Pendular Nystagmus (APN) may cause distressing visual symptoms in patients who are already suffering a severe general disease. Averbuch-Heller et al. conducted the first double-blind controlled study on treatment for APN. They showed that gabapentin substantially reduces pendular nystagmus and significantly increases visual acuity in the majority of patients. We present a patient with APN due to multiple sclerosis who suffered severe oscillopsy and reduction of visual acuity and who substantially benefited from a trial treatment with this agent.

Acetates↗

PubMed2000

The sensitivity and specificity of TOP, FDP and GDX in screening for early glaucoma.

The purpose of this study was to evaluate the efficacy of three screening tests in detecting glaucoma in its early stage: the Tendency Oriented Perimetry (TOP) and Frequency Doubling Perimetry (FDP) visual field tests, and the Glaucoma Diagnostic (GDx) nerve fibre layer analyser. Eighteen patients with glaucoma who showed an early defect on HFA c 24-2 and twenty normals underwent the three tests. TOP showed a sensitivity of 94.4% and a specificity of 75%, FDP showed a sensitivity of 72.2% and a specificity of 100%, and GDx a sensitivity of 77.7% and a specificity of 60%.

Aged↗

PubMed2000

[Chronic open angle glaucoma and cataract: when is it necessary to perform combined surgery?].

The combined surgical treatment of cataract and glaucoma has a long and controversial history (1). The guidelines proposed by the European Glaucoma Society facilitate however the therapeutic decisions (2). If the patient with open-angle glaucoma is stabilized with medical treatment it is often sufficient to operate the cataract alone and continue the medical treatment afterwards. If the patient is not stabilized or if the medical treatment is not well tolerated, it is suggested to perform a combined procedure. If visual functions are threatened by the glaucoma it is better to perform the filtering procedure first. We shall overview these options and elaborate on each surgical technique.

Cataract↗

PubMed2000

Incidence of nd:Yag capsulotomy after lens implantation of an Acrylic IOL in one eye and a Silicone IOL in the other eye of the same patient: a preliminary study.

We retrospectively reviewed the charts of 40 patients who underwent an uneventful phacoemulsification in both eyes and had an Acrylic IOL (AcrySof) implanted in one eye and a Silicone IOL (SI 30/S 140) in the other. A subset of 18 patients had a mean follow up of 1 1/2 year. In the Acrylic group 1 patient (5.5%) underwent a posterior Yag-capsulotomy. In the Silicone group 6 patients (30%) underwent a Yag-capsulotomy. (2 anterior--4 posterior) (p = 0.04) Acrylic IOL's were associated with a significantly reduced incidence rate of Yag-capsulotomy compared with silicone IOL's after 1 1/2 years.

Biocompatible Materials↗

PubMed1999

The long-term effect of Yag laser posterior capsulotomy on intraocular pressure after combined glaucoma and cataract surgery.

In order to evaluate the long-term effect of Yag laser posterior capsulotomy on intraocular pressure (IOP) after combined cataract and glaucoma surgery, we retrospectively studied 20 patients who underwent posterior capsulotomy after single-site combined phacoemulsification and trabeculectomy. We assessed mean IOP and number of glaucoma medications. The mean follow-up was 3 months (range 1 to 6 months). Mean IOP's remained almost unchanged, and were 13.9 +/- 2.7 before and 14.8 +/- 3 mmHg after capsulotomy (p = 0.115). The mean number of medications (0.4) remained unchanged. We conclude that Yag laser posterior capsulotomy does not significantly affect bleb function or glaucoma medication use in patients who underwent combined phacoemulsification and trabeculectomy.

Aged↗