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Biomedical subjects

J B Jonas

Publications and source records attributed to J B Jonas.

At least 55 records · Page 3Linked to original sources
PubMed2003

[Readaptation time after photo-stress in normal subjects and glaucoma patients].

PURPOSE: A photo-stress test was conducted at the subjective contrast threshold to evaluate whether psychophysical differences could be detected between chronic open-angle glaucoma patients and normal subjects. METHODS: The prospective, comparative, clinical observational study included 20 patients (29 eyes) with chronic open-angle glaucoma and 20 control subjects (29 eyes). The study groups did not vary significantly in age and refractive error, but visual acuity showed a difference of 0.16. All participants underwent photo-stress using the Kontrastometer BA4. RESULTS: In the glaucoma group compared with the control group, the mean contrast threshold was significantly higher and the readaptation time significantly longer. The latter correlated significantly with the papillo-morphological glaucoma stage. CONCLUSIONS: In patients with chronic open-angle glaucoma, the foveal recovery time after a photo-stress test is significantly prolonged compared with normal subjects. It may suggest involvement of the fovea in glaucoma even if the visual acuity is 20/20.

Chronic Disease↗
PubMed2003

Intraocular pressure after intravitreal injection of triamcinolone acetonide.

AIM: To investigate the intraocular pressure (IOP) response after intravitreal injections of triamcinolone acetonide as treatment of intraocular neovascular or oedematous diseases. METHODS: The prospective consecutive non-comparative interventional case series study included 71 patients (75 eyes) with progressive exudative age related macular degeneration (n = 64 eyes) or diffuse diabetic macular oedema (n = 11 eyes), who received an intravitreal injection of 25 mg triamcinolone acetonide. Mean follow up time was 6.86 (SD 2.52) months (range 3.1-14.47 months). RESULTS: IOP increased significantly (p<0.001) from 15.43 (3.26) mm Hg preoperatively to a mean maximum of 23.38 (8.37) mm Hg (range 13-64 mm Hg) postoperatively. An IOP rise to values higher than 21 mm Hg was observed in 39 (52%) eyes. Elevation of IOP occurred about 2 months after the injection. Preoperative predictive factor for the rise in IOP was younger age (p=0.013). It was statistically independent of refractive error, presence of diabetes mellitus, and indication for the injection. In all but one eye, IOP could be lowered to the normal range with topical medication, without development of glaucomatous optic nerve head changes. In the eyes with an elevation of IOP, IOP normalised about 6 months after the injection, without further medication. Eyes undergoing repeatedly intravitreal injections of triamcinolone acetonide showed only an elevation of IOP, if after the first injection a rise of IOP had occurred. CONCLUSIONS: After intravitreal injections of 25 mg of triamcinolone acetonide, an IOP elevation can develop in about 50% of eyes, starting about 1-2 months after the injection. In the vast majority, IOP can be normalised by topical medication, and returns to normal values without further medication about 6 months after the injection.

Aged↗
PubMed2003

Optic disc morphology in south India: the Vellore Eye Study.

AIM: To evaluate the morphology of the optic nerve head in an unselected population group in south India. METHODS: The study included 70 subjects forming a population based sample, selected in a random manner. Mean age was 47.5 (SD 8.7) years, mean refractive error measured -0.07 (1.11) dioptres (range -4.50 to +2.50 dioptres). Optic disc slides were morphometrically analysed. RESULTS: Mean optic disc area measured 2.58 (0.65) mm(2). It was statistically independent of age and refractive error. Optic disc shape was slightly vertically oval. Mean neuroretinal rim area was 1.60 (0.37) mm(2). It was significantly and positively correlated with optic disc size and optic cup size. It was independent of age, sex, refractive error, and axial length. In all subjects included in the study, the rim was smallest in the temporal horizontal optic disc sector. Mean horizontal cup/disc diameter ratio (0.66 (0.07)) was significantly (p<0.001) higher than the mean vertical cup/disc diameter ratio (0.56 (0.08)). Both ratios were highly significantly (p <0.001) and positively correlated with optic disc size. The alpha zone of parapapillary atrophy (0.84 (0.29) mm(2)), and beta zone (0.13 (0.38) mm(2)), respectively, occurred in 69 (98.6%) subjects and in eight (11.4%) subjects, respectively. They were significantly larger in the temporal horizontal sector. The alpha zone was significantly (p<0.001) larger and occurred significantly more often than beta zone. Retinal arterioles and venules were wider, and in spatial correlation, the visibility of the retinal nerve fibre layer was significantly better, in the temporal inferior disc arcade and the temporal superior arcade than in the nasal superior arcade and the nasal inferior vessel arcade. Except for the absolute size measurements these optic nerve head parameters did not differ markedly (p >0.05) from the values found in white people. CONCLUSIONS: South Indians and white people do not show marked differences in the morphology of the optic nerve head as measured by morphometric optic disc parameters, with the possible exception of the absolute optic disc dimensions.

Adult↗
PubMed2003

Intravitreal triamcinolone acetonide for exudative age related macular degeneration.

AIM: To evaluate the effect of intravitreal triamcinolone acetonide on the visual acuity of patients with exudative age related macular degeneration, to assess the duration of a possible effect, and to evaluate clinical side effects of the treatment. METHODS: The study included 67 patients (71 eyes) who presented with exudative age related macular degeneration of predominantly or total occult type (n = 68) or classic type (n = 3), and who received once, or repeatedly, an intravitreal injection of 25 mg of crystalline triamcinolone acetonide. Mean follow up time was 7.46 (SD 3.54) months (range 3.1-19.57 months). RESULTS: Visual acuity increased significantly (p <0.001) from 0.16 (0.11) to a mean maximum of 0.23 (0.17). Postoperative visual acuity was highest 1-3 months after the injection. 47 (66.2%) eyes gained in maximal visual acuity and 11 (15.5%) eyes lost in visual acuity. Intraocular pressure increased significantly (p <0.001) from 15.1 (3.1) mm Hg at baseline to a maximal value of 23.0 (8.25) mm Hg. At the end of follow up, intraocular pressure again decreased significantly (p<0.001) to 16.8 (4.9) mm Hg. No cases of postoperative infectious endophthalmitis, rhegmatogenous retinal detachment, or proliferative vitreoretinopathy occurred. Owing to a decrease in visual acuity after an initial increase, six patients received a second intravitreal triamcinolone acetonide injection after which visual acuity increased again in three eyes. CONCLUSIONS: Intravitreal injection of 25 mg of crystalline triamcinolone acetonide merits further study for the treatment of exudative age related macular degeneration.

Aged↗
PubMed2003

Reproducibility of ophthalmodynamometric measurements of central retinal artery and vein collapse pressure.

BACKGROUND: To assess the reproducibility of ophthalmodynamometric measurements using a new, Goldmann contact lens associated, device allowing biomicroscopic visualisation of the optic disc. METHODS: The prospective clinical study included 87 eyes of 58 subjects presenting with a normal fundus (n=40), or ocular diseases (n=47). With topical anaesthesia, a Goldmann contact lens, fitted with a pressure sensor mounted into the holding ring of the contact lens, was placed onto the cornea. Pressure was applied onto the globe through the contact lens, and the pressure values obtained when the central retinal vessels started pulsating were noted. The measurements were performed 10 times. RESULTS: The mean coefficients of variation for redeterminations of the collapse pressure of the central retinal vein and artery were 16.3% (SD 11.4%), and 8.5% (4.1%), respectively. CONCLUSIONS: A simple and new, Goldmann contact lens associated, ophthalmodynamometer allows central retinal artery and vein collapse pressure measurements which are reproducible in a clinical setting.

Adult↗
PubMed2003

Central retinal artery and vein collapse pressure in eyes with chronic open angle glaucoma.

AIMS: To determine central retinal vessel collapse pressure in chronic open angle glaucoma. METHODS: For 19 eyes with chronic open angle glaucoma and 27 eyes of a control group, central retinal vessel collapse pressure was measured by a Goldmann contact lens fitted with a pressure sensor in its holding grip. RESULTS: Central retinal vein collapse pressure was significantly (p=0.001) higher in the glaucoma group than in the control group (26.1 (SD 26.4) relative units versus 6.1 (8.4) relative units). CONCLUSIONS: Measured by a new ophthalmodynamometer, central retinal vein collapse pressure measurements may be abnormally high in eyes with chronic open angle glaucoma.

Adult↗
PubMed2003

Factors influencing visual outcome after penetrating keratoplasty combined with intraocular lens implantation.

PURPOSE: To establish which factors influence visual outcome after penetrating keratoplasty combined with intraocular lens implantation. METHODS: This retrospective noncomparative clinical interventional case series study included 135 consecutive patients (mean age 70.2 +/- 13.6 years) who underwent central penetrating allogenic keratoplasty combined with intraocular lens (IOL) implantation, all operated by the same surgeon. There were 79 triple procedures, 33 keratoplasties combined t with an exchange of OL, and 23 penetrating keratoplasties combined with a secondary implantation of posterior chamber lens. Mean follow-up was 28.3 +/- 18.7 months (range 3.3-112 months). Reasons for keratoplasty were herpetic or traumatic corneal scars or defects (46), Fuchs corneal endothelial dystrophy (22), pseudophakic or aphakic bullous keratopathy (49), corneal endothelial decompensation due to other reasons (15), and keratoconus (3). Main outcome measures were postoperative visual acuity and agin in visual acuitvy RESULTS: Mean postoperative visual acuity and mean gain in visual acuity were 0.33 +/- 0.21 (median 0.30) and 0.25 +/- 0.20 (median 0.20), respectively. Compared with the preoperative measurements, mean visual acuity increased in 129 patients (129 /135, 95.6%). Factors influencing postoperative visual outcome and gain in visual acuity were preoperative visual acuity (p < 0.005), reason for keratoplasty (p < 0.005), and diameter of the graft (p = 0.046). ostoperative visual outcome was independent of age, sex, right or left eye, presence of diabetes mellitus, preoperative refractive error, length of follow-up, duration of surgery, and preoperative intraocular pressure. CONCLUSIONS: The most important factors influencing visual outcome after central penetrating allogenic keratoplasty combined with IOL surgery are preoperative visual acuity, graft size, and reason for keratoplasty. Other factors such as age, sex, diabetes mellitus, and preoperative refractive error do not substantially influence postoperative visual outcome.

Adolescent↗
PubMed2003

Ocular findings in cerebro-oculo-facial-skeletal syndrome (Pena-Shokeir-II syndrome).

PURPOSE: To report the ocular findings in cerebro-oculo-facial-skeletal syndrome or Pena-Shokeir-II syndrome. METHODS: Case report. RESULTS: A five-month-old male infant presented with bilateral posterior polar cataract, microphthalmos, nystagmus, and marked non-glaucomatous optic nerve atrophy. Systemic abnormalities such as microcephaly, micrognathia, flexion contractures of the elbows and knees, hypotonic musculature, and failure to thrive, with pronounced statomotor retardation, led to the diagnosis of cerebro-oculo-facial-skeletal syndrome or Pena-Shokeir-II syndrome. Cataract surgery did not improve the poor visual performance. CONCLUSIONS: Cerebro-oculo-facial-skeletal syndrome (Pena-Shokeir-II syndrome) should be included in the differential diagnosis of bilateral microphthalmos, congenital cataract, nystagmus, and pronounced optic nerve atrophy, and cataract surgery does not markedly improve vision.

Abnormalities, Multiple↗
PubMed2003

Cystoid macular edema associated with latanoprost therapy in a pseudophakic vitrectomized patient after removal of silicone oil endotamponade.

PURPOSE: To describe the occurrence of cystoid macular edema in a pseudophakic vitrectomized patient following use of latanoprost (0.005%). METHODS: A 58-year-old patient underwent routine cataract surgery with posterior chamber lens implantation complicated by rhegmatogenous retinal detachment three months later. A pars plana vitrectomy was performed with silicone oil endotamponade which was removed six months later. Five months after oil removal, the patient presented with secondary open-angle glaucoma treated with latanoprost 0.005% eye drops once daily. RESULTS: Two weeks after initiation of latanoprost treatment, visual acuity dropped from 0.8 to 0.3 due to cystoid macular edema confirmed by fluorescein angiography. After discontinuing latanoprost therapy and with topical corticosteroid treatment, cystoid macular edema slowly resolved, and within 6 months, visual acuity improved to 0.8. CONCLUSIONS: Despite its marked ocular hypotensive effect, latanoprost should be carefully used in patients after uncomplicated cataract surgery if the vitreous body was removed by pars piana vitrectomy.

Antihypertensive Agents↗
PubMed2003

Intravitreal triamcinolone acetonide as an additional tool in pars plana vitrectomy for proliferative diabetic retinopathy.

PURPOSE: To evaluate the safety and efficacy of intravitreal injections of crystalline triamcinolone acetonide as an adjunctive procedure in pars plana vitrectomy for proliferative diabetic retinopathy. METHODS: This nonrandomized comparative study included 30 patients (32 eyes) who underwent standardized pars plana vitrectomy for treatment of proliferative diabetic retinopathy and who received an intravitreal injection of 25 mg triamcinolone acetonide at the end of surgery. Mean follow-up time was 5.60 +/- 5.14 months. The study group was compared with a control group (32 eyes) matched with the study group for preoperative and intraoperative parameters and who underwent pars plana vitrectomy for proliferative diabetic retinopathy without intravitreal injection of triamcinolone acetonide. RESULTS: The study group and the control group did not vary significantly in frequency of postoperative retinal detachment, re-pars plana vitrectomy, or postoperative enucleation or phthisis bulbi, or in best postoperative visual acuity, visual acuity at end of the study, or gain in visual acuity. CONCLUSIONS: In this pilot study, the study group with pars plana vitrectomy and intravitreal triamcinolone acetonide injection compared with the nonrandomized control group without intravitreal triamcinolone acetonide injection did not show a higher than usual rate of postoperative complications. As a corollary, however, the data do not suggest the adjunct use of 25 mg intravitreal triamcinolone acetonide combined with pars plana vitrectomy as treatment of proliferative diabetic retinopathy.

Adult↗
PubMed2003

Intravitreal triamcinolone acetonide as treatment of ischemic ophthalmopathy.

PURPOSE: To describe the clinical course of a patient receiving repeated intravitreal injections of triamcinolone acetonide (25 mg) as treatment of ischemic ophthalmopathy. METHODS: A 70-year-old patient with Waldenström disease presented with progressive iris neovascularization, vitreous hemorrhage, and ocular hypotony due to ischemic ophthalmopathy. Visual acuity was 0.05. Within 2.5 years, he received three intravitreal injections of 25 mg of triamcinolone acetonide. Additionally, penetrating keratoplasty and synechiolysis were performed during the follow-up. RESULTS: After each intravitreal injection, visual acuity and intraocular pressure increased, iris neovascularization regressed, and vitreous haze cleared up. CONCLUSIONS: Intravitreal triamcinolone acetonide may induce regression of iris neovascularization, increase intraocular pressure, and improve visual acuity in eyes presenting with ocular hypotony, vitreous hemorrhage, and progressive intraocular neovascularization due to ischemic ophthalmopathy.

Aged↗
PubMed2003

Treatment of keratoconus by toric foldable intraocular lenses.

PURPOSE: To report on the correction of marked regular corneal astigmatism due to keratoconus by toric intraocular lenses (IOL). SETTING: University eye hospital. METHODS: A 66-year-old woman presented with cataract and unilateral keratoconus (keratometric readings: 50.2/41.3 diopters [D]). She underwent routine cataract surgery with implantation of a foldable posterior chamber toric IOL (refractive power: +10.0 D sphere/+12.0 D cylinder). A 68-year-old surgically aphakic woman presented with peripheral accentuated keratoconus with regular and stable corneal astigmatism (keratometric readings: 39.75/61.5 D). She underwent secondary implantation of a foldable toric IOL (refractive power: -9.0 D sphere/+30.0 D cylinder) into the ciliary sulcus. RESULTS: After a follow-up period of 4 months, visual acuity increased to 0.70 with a correction of +0.75 sphere -2.5 cylinder/84 degrees in Patient 1; after a follow-up period of 6 months, visual acuity increased to 0.60 with a correction of +1.0 -2.0/90 degrees in Patient 2. CONCLUSIONS: Foldable toric silicone IOL may be a surgical option in the management of regular marked corneal astigmatism caused by keratoconus.

Aged↗
PubMed2002

Is the nasal optic disc sector important for morphometric glaucoma diagnosis?

BACKGROUND/AIM: Since the central retinal vessel trunk usually located in the nasal optic disc sector can render difficult the delineation of the neuroretinal rim and optic disc, the aim of this study was to evaluate whether the nasal region of the optic nerve head is important, or can be left out, for the morphometric glaucoma diagnosis. METHODS: The clinical observational study included 1337 patients with primary or secondary open angle glaucoma and 649 normal subjects. The glaucoma group was divided into 1187 patients with glaucomatous visual field defects ("perimetric glaucoma"), and into 150 patients with optic nerve head changes and normal visual fields ("preperimetric glaucoma"). Colour stereo optic disc photographs were morphometrically evaluated. RESULTS: Highest diagnostic power for the separation between the normal group and the perimetric glaucoma group, and for the differentiation between the normal group and the preperimetric glaucoma group, had the sum of inferotemporal rim area plus superotemporal rim area, the sum of inferotemporal rim area plus superotemporal rim area plus temporal rim area, and the inferotemporal rim area as single parameter. The lowest diagnostic precision had the nasal rim area as single parameter or in combination with rim measurements in other disc sectors. CONCLUSION: Excluding the nasal optic disc sector does not markedly decrease the diagnostic power of morphometric optic disc analysis in glaucoma diagnosis. It may have importance for an automated computerised morphometric detection of glaucomatous optic nerve damage.

Adult↗
PubMed2001

Prevalence and causes of visual field loss in the elderly and associations with impairment in daily functioning: the Rotterdam Study.

OBJECTIVES: To determine the prevalence and causes of visual field loss (VFL) and the association between VFL and indicators of impairment in daily functioning. DESIGN: Population-based cohort study. SETTING: Suburb of Rotterdam, the Netherlands. PARTICIPANTS: Community-dwelling elderly residents (n = 6250). MAIN OUTCOME MEASURE: Visual field loss on suprathreshold static, Goldmann kinetic perimetry, or both. METHODS: Suprathreshold testing of the central visual field was performed on both eyes and repeated if results were abnormal or unreliable. Goldmann perimetry was performed to confirm defects. Causes were determined using ophthalmologic and neurologic examination data and medical records. Impairment was assessed using data from interviews and medical records on disability in daily life, falling, and fractures. RESULTS: The overall prevalence of VFL was 5.6% (3.0% in those aged 55-64 years to 17.0% in those > or =85 years); glaucoma was the leading cause in all age groups. Before age 75 years, other optic nerve diseases and stroke ranked second and third, respectively, as did age-related macular degeneration and retinal vascular occlusive disease, respectively, after this age. Also, after adjustment for visual acuity, VFL was associated with disability, diminished enjoyment of reading and watching television, and a higher risk of incident falling. Risk of incident hip fracture was not increased. CONCLUSIONS: Visual field loss is present in 1 of every 20 community-dwelling elderly people and is associated with impaired daily functioning. Glaucoma is the leading cause in all age groups. Other high-ranking causes, some of which are partly preventable, vary by age.

Activities of Daily Living↗