Tension Glaucoma (tension + glaucoma)

Distribution by Scientific Domains

Kinds of Tension Glaucoma

  • normal tension glaucoma

  • Selected Abstracts

    Novel mutations in the MYOC/GLC1A gene in a large group of glaucoma patients,,

    HUMAN MUTATION, Issue 6 2002
    Karin Michels-Rautenstrauss
    Abstract Mutations at the myocilin (MYOC) gene within the GLC1A locus have been revealed in 2-4% of patients suffering primary open angle glaucoma (POAG) worldwide. In our ongoing glaucoma study sixhundred eighty two persons have been screend for MYOC mutations. The first group consisted of 453 patients from a long-term clinical study diagnosed either with juvenile OAG (JOAG), POAG, ocular hypertension (OHT) or normal tension glaucoma (NTG) plus 22 cases of secondary glaucoma. This group, and additional 83 healthy controls, is part of a long term study with repeated clinical examinations at the University of Erlangen-Nurnberg. An additional sample of 124 glaucoma patients or at risk persons referred from other sources were included in the mutation screening. Five novel mutations, namely Gly434Ser, Asn450Asp, Val251Ala, Ile345Met and Ser393Asn, could be identified as cause of preperimetric POAG, JOAG, normal tension POAG and POAG. Myocilin mutations were identified similar with previous reports with other ethnic populations at the rate of 11/341 (3.2%) probands. 2002 Wiley-Liss, Inc. [source]

    4121: Combined OCT retinal nerve fibre layer analysis and VEP in neuro-ophthalmic disease

    P GOOD
    Purpose Ocular Coherence Tomography (OCT) has become a valuable tool in assessing retinal nerve fibre layer thickness (RNFL) in Patients with optic nerve disease. This study is designed to compare RNFL thickness n with Visual Evoked Cortical Potentials (VECP)in patients with known optic nerve disease and comparing these to a group of patients with primary open angle glaucoma (POAG). Methods Twenty Patients (37 eyes) with clinically determined optic nerve disease underwent pattern reversal VECP and also OCT using a Spectralis OCT system. Assessment of global and segmental RNFL was made. Six Patients were diagnosed as Dominant Optic atrophy, 3 with Lebers Optic Neuropathy (LHON), 6 with Nutritional amblyopia, 3 with Anterior Ischaemic Optic Neuropathy (AION), and 2 with Demyelinating disease. These Patients were also compared to a group of 10 patients (20 eyes) with Primary Open Angle Glaucoma POAG. Results Pattern reversal VECP were abnormal in 32/37 eyes (86%): 26/32 (81%) of these being of reduced amplitude, and 20/32 (62%) being delayed. Amongst the patients with POAG only 4/20 eyes (20%) had abnormal VECP, and none were delayed. Thinning of the RNFL occurred in 36/37 eyes (97%) with optic nerve disease; 24 (65%) had global thinning, and the remainder segmental thinning only. All of the eyes with POAG had RNFL thinning but only 6/20 eyes (30%) had global thinning. Bipolar cell thinning of the central retina was noted in 6 eyes with optic nerve disease. Conclusion OCT is a valuable tool in the assessment of patients with optic nerve disease. Thinning of the RNFL was a more consistent finding than delay of the VECP in optic nerve disease, and a combination of VECP and OCT is helpful in the differential diagnosis of low tension glaucoma and optic nerve disease. [source]

    2326: Influence of change in body position on choroidal blood flow in patients with obstructive sleep apnea syndrome

    Purpose Obstructive sleep apnea syndrome (OSA) has been reported to be associated with ischemic and glaucomatous optic neuropathy (especially normal tension glaucoma). OSA per se is able to generate hypertension, atherosclerosis and autonomic dysfunction, all conditions possibly interacting with ocular vascular regulation. The aim of our study was to characterize the choroidal vascular reactivity to change in body position in OSA patients, as compared with matched healthy control subjects. Methods Eighteen newly diagnosed OSA patients were included in this prospective study. Control subjects were matched with OSA patients for body mass index (BMI), gender and age. At the screening visit, each subject underwent a general exam, cardiovascular, neurologic and ophthalmological examinations, and overnight polysomnography. The LDF instrument used in this study to measure subfoveal choroidal blood flow (ChBF), ChBVel , velocity (kHz); and volume, ChBVol (in arbitrary units, AU) Vascular choroidal reactivity was tested during the change in body position from the sitting to the supine position (10 min). Results OSA patients exhibited a similar choroidal reactivity during change in body position than controls with increased ChBVel (+15%), decreased ChBVol (-11.6%), and unchanged ChBF. IOP increased by 14.2% in the supine position whereas ocular perfusion pressure remained stable. Conclusion This prospective comparative study showed for the first time unimpaired choroidal vascular reactivity in otherwise healthy OSA patients. This suggests OSA patients, without comorbidities, has long-term adaptive mechanisms active in ocular microcirculation. [source]

    Evaluation of cerebrospinal fluid pressure in patients with Alzheimer's disease as a possible cause of glaucoma

    Purpose To investigate whether cerebrospinal fluid (CSF) pressure and trans-lamina cribrosa pressure gradient play a role in the pathogenesis of glaucoma. Our hypothesis is that a low cerebrospinal fluid (CSF) pressure may be correlated with the presence of glaucoma. The first objective is to investigate whether the CSF pressure in Alzheimer's disease (AD) patients with glaucoma is lower than in AD patients without glaucoma. The second goal is to evaluate an animal model with AD for the incidence and prevalence of glaucoma. If glaucoma is present histopathological analysis will be performed on retina and optic nerve, to search for Alzheimer-type changes. Methods Newly diagnosed AD suspects will undergo a lumbar puncture with CSF manometry, during neurological work-up. Ophthalmological evaluation consists of best corrected visual acuity, slit lamp biomicroscopy, gonioscopy, fundoscopy and pachymetry. Diagnosis of glaucoma or ocular hypertension will be made on the basis of visual field examination, optic disc evaluation and IOP measurement. Correlation between CSF pressure, trans lamina cribrosa pressure gradient and the presence of glaucoma will be calculated. The prevalence of low tension glaucoma will be compared to the prevalence of chronic open angle glaucoma with elevated IOP. In the second part of the project a genetically modified strain of mice with AD will be examined and screened for the development of glaucoma. Opthalmological examination will consist of IOP measurement, corneal pachymetry, optic disc evaluation and visual evoked potentials with flash. Histopathological analysis will be performed by the team of Prof De Deyn PP. Results will follow Conclusion will follow [source]

    Do patients with normal tension glaucoma have a thinner conjunctiva?

    Purpose The central cornea is thinner in patients with normal tension glaucoma (NTG). We had developed the surgical impression of thinner conjunctivas in patients with NTG. The purpose of this study was to determine whether there is a difference between the conjunctival thickness of patients with NTG and those with high tension primary open-angle glaucoma (POAG). Methods In this prospective study, 40 patients scheduled for trabeculectomy were categorized into NTG and POAG based on maximum intraocular pressure (IOP) as measured by Goldmann applanation tonometry. Ten (10) patients with NTG (max. IOP,21mmHg) and 30 patients with high tension POAG (max IOP>21mmHg) were included in the study. Conjunctival biopsies taken from the inferior fornix one month prior to trabeculectomy were fixed in formalin and embedded in Historesin. The conjunctival thickness was measured on a standardised way and compared between the two groups. Non-paired Student T test for two-tailed groups with equal variance was used for statistical analysis. Results The difference in mean conjunctival thickness between patients with NTG (66.4,21.1) and patients with high tension POAG (104.6,44.3) was statistically significant (P=0.045). The mean CCT in NTG (537,619.6) was lower than in POAG (548.338.0), but did not reach significancy in this study. Conclusion Patients with NTG have a thinner conjunctiva than those with high tension POAG [source]

    Abnormal peripheral vascular response to occlusion provocation in normal tension glaucoma patients

    Purpose: To assess peripheral vascular reactive hyperemia in response to occlusion provocation test, using two-channels laser Doppler probe in patients with normal tension glaucoma (NTG) and normal subjects. Methods: 15 patients with NTG (12 women and 4 men), mean aged 58,9 and 15 control subjects (13 women and 2 men), mean aged 60,6 were subjected to an occlusion test. The experiment comprised following steps: 1/ a 5-minute baseline-period 2/ a 2-minute occlusion of the left hand using a 15 cm wide cuff located directly over the elbow (the pressure in the cuff was 50 mmHg higher than the systolic pressure measured on the arm 3/ a 15- minute final recovery period after occlusion. Finger hyperemia was assessed by two-channels laser-Doppler flowmeter MBF-3d, Moor Instruments, Ltd., continuously during the experiment. For measurements of hyperemia two surface probes were attached to the pulp of the second finger (mean probe) and third finger (basic probe) of the left hand. The following hyperemia parameters were measured: RF (rest flow), BZ (biological zero), TM (time to peak flow), TH (half-time of hyperemia), MAX (maximum of hyperemia) and hyperemia amplitude (MAX-RF)/RF 100% was calculated. Kruskal-Wallis test analysis was used to test the differences between the group of patients and normal subjects for TM1,MXF1 (basic probe) and TM2, MXF2 (mean probe) parameters. Results: In NTG patients, TM1 was significantly higher comparing with healthy subjects whereas MAX was significantly lower as compared to the control group. Conclusions: Occlusion provocation test elicits a different systemic hyperemia response in patients with NTG compared with healthy subjects. [source]

    Evaluation of central corneal thickness in patients affected by ocular hypertension, primary open-angle glaucoma, normal tension glaucoma

    L. Quaranta
    No abstract is available for this article. [source]

    Corneal thickness in glaucoma: an important parameter?

    P. Brusini
    Summary Central corneal thickness was measured by pachometry in 49 patients with primary open-angle glaucoma (POAG), 41 with ocular hypertension (OHT), 14 with normal tension glaucoma (NTG) and 48 normal subjects. The mean corneal thickness of the OHT patients was significantly greater than that of the normal control group. The NTG patients, on the other hand, had a cornea on average thinner than the normals. These differences may cause misclassification of normals with a thick cornea as ocular hypertensive eyes or, contrarywise, cause those normals whose IOP is underestimated because of a thin cornea to be classed as NTG patients. [source]

    The management of normal tension glaucoma

    Julian Sack MB BS FRACO
    Objective: To outline the difficulties in making management decisions associated with normal tension glaucoma. To suggest treatment strategies according to the clinical presentation of the disease. Method: Literature review and findings based on clinical experience. Conclusions: The treatment of normal tension glaucoma involves many difficult decisions including whether to intervene and, if so, when and how to treat. Providing the patient with information is essential to gain co-operation and confidence. At present, the treatment objectives are to prevent further visual field loss by reduction of intraocular pressure by 30 per cent or more. This may be achieved by using medical or surgical regimens. Recently, there has been emphasis on the use of neuroprotective drugs that may act independently of the effect of intraocular pressure lowering. The balance between protecting vision and iatrogenic damage is not always easy. [source]

    Morphometric differences between optic discs in high tension and normal tension glaucomas

    M. Iester
    No abstract is available for this article. [source]