1: Invest Ophthalmol Vis Sci. 2010 Mar 5; [Epub ahead of print] 

Effects of Bone Marrow Mesenchymal Stem Cells Transplantation on Light-Damaged
Retina.

Zhang Y, Wang W.

Peking University Third Hospital, Peking University Eye Center, Beijing, China.

Purpose: to investigate the effects and possible mechanisms of rat bone marrow
mesenchymal stem cells (BMSCs) transplantation on light-damaged retinal
structure and the apoptosis of photoreceptors. Methods: 4' 6- diamidino
-2-phenylindole (DAPI)-labeled BMSCs were transplanted into the subretinal space
of light-damaged Sprague-Dawley (SD) rats 10 days after exposure. BMSCs were
cultivated with the supernatant of homogenized retina (SHR). Results: Compared
with the phosphate buffered solution (PBS) injection group and the light damage
group, the outer nuclear layer (ONL) contained significantly more cells and the
percentage of apoptotic ONL cells was significantly reduced in the BMSCs
transplantation group. Most DAPI-labeled BMSCs expressed brain-derived
neurotrophic factor (BDNF). There was elevated basic fibroblast growth factor
(bFGF) and BDNF immunoreactivity in the retinas of the BMSCs transplantation
group, as compared with the light damage group. In vitro culture showed that 10%
BMSCs changed from fusiform shape to multipolar shape. A fraction of cells
expressed MAP2 or GFAP, and some cells expressed bFGF or BDNF when cultivated
with light-damaged SHR for 7 days. Conclusion: BMSCs subretinal transplantation
could inhibit photoreceptors apoptosis and slow down retinal damage in
light-damaged eyes. BMSCs could express bFGF (in vitro) and BDNF (in vitro and
in vivo), pointing to potential trophic and protective effects on light-damaged
retinas.

PMID: 20207980  [PubMed - as supplied by publisher]

2: Invest Ophthalmol Vis Sci. 2010 Mar 5; [Epub ahead of print] 

Prevalence of Amblyopia and Strabismus in Young Singaporean Chinese children.

Chia A, Dirani M, Chan YH, Gazzard G, Au Eong KG, Selvaraj P, Ling Y, Quah BL,
Young T, Mitchell P, Varma R, Wong TY, Saw SM.

Paediatric Services, Singapore National Eye Centre, Singapore, Singapore.

Purpose: To determine the prevalence of amblyopia and strabismus in young
Singapore Chinese children. Methods: 3009 Singaporean children, aged 6 -72
months, underwent complete eye examinations and cycloplegic refraction. Visual
acuity (VA) was measured with logMAR chart when possible, and Sheridan Gardner
test when not. Strabismus was defined as any manifest tropia. Unilateral
amblyopia was defined as a 2-line difference between eyes with VA<20/30 in the
worse eye, and with coexisting anisometropia (>/=1.00D for hyperopia, >/=3.00D
for myopia, >/=1.50D for astigmatism), strabismus or past/present visual axis
obstruction. Bilateral amblyopia was defined as VA in both eyes <20/40 (in
children 48-72months) and <20/50 (<48months), with coexisting hyperopia >/=
4.00D, myopia /=2.50D, or past/present visual axis
obstruction. Results: The amblyopia prevalence in children aged 30 to 72 months
was 1.19% (95% confidence interval, CI, 0.73-1.83) with no age (p=0.37) or
gender (p=0.22) differences. Unilateral amblyopia (0.83%) was twice as frequent
as bilateral amblyopia (0.36%). The most frequent causes of amblyopia were
refractive error (85%) and strabismus (15%); anisometropic astigmatism >1.50D
(42%) and isometropic astigmatism >2.50D (29%) were frequent refractive errors.
The prevalence of strabismus in children aged 6 to 72 months was 0.80% (95%CI
0.51-1.19), with no gender (p=0.52) or age (p=0.08) effects. The exotropia:
esotropia ratio was 7:1 with most exotropia being intermittent (63%). Of
children with amblyopia, 15.0% had strabismus, while 12.5% of children with
strabismus had amblyopia. Conclusion: The prevalence of amblyopia was similar
while the prevalence of strabismus was lower than in other populations.

PMID: 20207979  [PubMed - as supplied by publisher]

3: Invest Ophthalmol Vis Sci. 2010 Mar 5; [Epub ahead of print] 

Correlation of relative afferent pupillary defect and retinal nerve fiber layer
loss in unilateral or asymmetrical demyelinating optic neuropathy.

Younis A, Eggenberger E.

Neurology and Ophthalmology, Michigan State University, East lansing, United
States.

PURPOSE: To investigate the relationship between the relative afferent pupillary
defect (RAPD) and retinal nerve fiber layer (RNFL) thickness assessed by optical
coherence tomography (OCT) in patients with unilateral or asymmetrical
demyelinating optic neuropathy. METHODS: Seventy-two patients with unilateral or
asymmetrical demyelinating optic neuropathy were retrospectively evaluated. The
RAPD was measured by the swinging flashlight method using neutral density
filters, and RNFL thickness was measured with the Stratus OCT. Relationships
between the RAPD and RNFL thickness difference/ ratio between the two eyes (in
superior, inferior, temporal, nasal quadrants and total thickness) were
evaluated by linear regression. Coefficients of determination (R2) were
calculated using a multivariate model. RESULTS: The mean RNFL thickness in the
more affected eyes was 82.7 +/- 18.7microm and in the fellow eyes was 88.9 +/-
13.97microm (R2 = 0.406, P < 0.0001). The RAPD size correlated significantly
with both RNFL thickness difference (total: R2 = 0.191, P < 0.0001, superior: R2
= 0.203, P < 0.0001, inferior: R2 = 0.126, P= 0.002, temporal: R2 = 0.059,
P=0.040, nasal: R2 = 0.062, P= 0.035) and RNFL thickness ratio ( total: R2 =
0.325, P = 0.0001, superior : R2 = 0.339, P < 0.0001, inferior: R2 = 0.256, P <
0.0001, temporal: R2 = 0.151, P = 0.0001, nasal: R2 = 0.156, P= 0.001).
CONCLUSIONS: The RAPD as measured in log units significantly correlated with the
total and quadrantic RNFL thickness differences and ratios; the total, superior
and inferior quadrant data produced the strongest correlations.

PMID: 20207978  [PubMed - as supplied by publisher]

4: Invest Ophthalmol Vis Sci. 2010 Mar 5; [Epub ahead of print] 

FLUOROPHOTOMETRIC STUDY OF THE EFFECT OF the GLAUKOS TRABECULAR MICRO-BYPASS
STENT ON AQUEOUS HUMOR DYNAMICS.

Fernandez-Barrientos Y, Garcia-Feijoo J, Martinez de la Casa JM, Pablo LE,
Fernandez-Perez C, Garcia Sanchez J.

Instituto de Investigaciones Ramon Castroviejo, Hospital Clinico Universitario
San Carlos, Madrid, Spain.

Purpose: To evaluate the changes in aqueous humor dynamics and the efficacy and
safety of the iStent(R) in combination with cataract surgery. Methods:
Prospective, randomized, clinical study in patients with open-angle glaucoma or
ocular hypertension, undergoing cataract surgery. Aqueous flow (F) and
trabecular outflow facility (CT) was measured by fluorophotometry preoperatively
and at months 1, 6 and 12 in both groups. Results: Thirty-three eyes of 33
patients were randomized to either two stents and cataract surgery (n=17, Group
1) or cataract surgery alone (n=16, Group 2). Preoperatively, F and CT were
similar in Groups 1 and 2 (1.78 +/- 0.44 and 1.74 +/- 0.82 microl/min, p=0.18;
0.12 +/- 0.03 and 0.13 +/- 0.06 microl/min/mmHg, p=0.71, respectively).
Postoperatively, there were no changes of note in F, however, CT increased in
both groups. At one year, CT was 0.45+/-0.27 microl/min/mmHg in Group 1 and
0.19+/-0.05 microl/min/mmHg in Group 2 (p=0.02), which represented increases of
275% and 46%, respectively. Mean IOP reduction was also greater in Group 1 than
in Group 2 (6.6 +/- 3.0 vs. 3.9 +/- 2.7 mmHg; p=0.002). The mean number of
medications was significantly lower in Group 1 vs. Group 2 (0.0 vs. 0.7 +/- 1.0,
respectively; p=0.007). Conclusions: Compared with cataract surgery alone,
implantation of the iStent(R) concomitant with cataract extraction significantly
increased the trabecular outflow facility, achieved IOP reduction, and reduced
the number of medications at one year. Longer follow-up is needed to assess the
long-term effect on outflow facility.

PMID: 20207977  [PubMed - as supplied by publisher]

5: Invest Ophthalmol Vis Sci. 2010 Mar 5; [Epub ahead of print] 

Use of single-vision distance spectacles improves landing control during step
descent in well-adapted multifocal lens-wearers.

Timmis MA, Johnson L, Elliott DB, Buckley JG.

Division of Medical Engineering, School of Engineering Design & Technology,
University of Bradford, Bradford, United Kingdom.

Purpose: Epidemiological research has shown that multifocal spectacle wearers
(bifocal and progressive addition lenses, PALs) are more than twice as likely to
fall compared with non-multifocal spectacle wearers with this risk further
increasing when negotiating stairs. The present study investigated whether
step/stair descent safety is improved by using single-vision distance lenses.
Methods: From a stationary standing position on top of a block, twenty long-term
multifocal wearers stepped down (from different block heights) onto a lower
level wearing either bifocal, PALs or single-vision distance lenses. Results:
Use of single-vision distance spectacles lead to an increased single-limb
support time, a reduced ankle and knee angle and vertical centre-of-mass
velocity at contact with the lower level, and a reduced ankle angular velocity
and vertical centre-of-mass velocity during initial landing (p < 0.03). These
findings indicate that landing occurred in a more controlled manner when wearing
single-vision distance spectacles, rather than tending to 'drop' onto the lower
level as occurred when wearing bifocals or PALs. Conclusion: Use of
single-vision distance spectacles lead to improvements in landing control,
consistent with individuals being more certain regarding the precise height of
the lower floor level. This was attributed to having a view of the foot, step
edge and immediate floor area that was not blurred, magnified or doubled and
that did not suffer from image jump or peripheral distortions. These findings
provide further evidence that use of single-vision distance lenses in everyday
locomotion may be advantageous for elderly multifocal wearers who have a high
risk of falling.

PMID: 20207976  [PubMed - as supplied by publisher]

6: Invest Ophthalmol Vis Sci. 2010 Mar 5; [Epub ahead of print] 

Ocular Risk Factors for Choroidal Neovascularization in Pathological Myopia.

Ikuno Y, Jo Y, Hamasaki T, Tano Y.

Ophthalmology, Osaka University Medical School, Suita, Japan.

PURPOSE. To identify the risk factors for development of myopic choroidal
neovascularization (mCNV), a major cause of visual impairment. METHODS. We
included 23 consecutive patients with bilateral high myopia (axial length
>/=26.5 mm or refractive error PMID: 20207975  [PubMed - as supplied by publisher]

7: Invest Ophthalmol Vis Sci. 2010 Mar 5; [Epub ahead of print] 

Histamine reduces flash sensitivity of ON retinal ganglion cells in primate
retina.

Akimov NP, Marshak DW, Frishman L, Glickman RD, Yusupov RG.

Physiology, University of Texas Health Science Center, San Antonio, United
States.

Purpose. In Old World primates, the retina receives input from histaminergic
neurons in the posterior hypothalamus. They are a subset of the neurons that
project throughout the central nervous system and fire maximally during the day.
In order to learn how they contribute to vision, we applied histamine to a dark
adapted, superfused baboon eyecup preparation while recording extracellularly
from peripheral retinal ganglion cells. Methods. The stimuli were 5 ms, 560 nm,
weak, full-field flashes in the low scotopic range. Ganglion cells with
sustained and transient ON responses and two cell types with OFF responses were
distinguished; their responses were recorded with a 16-channel microelectrode
array. Results. Low micromolar doses of histamine decreased the rate of
maintained firing and the light sensitivity of ON ganglion cells. Both sustained
and transient ON cells responded similarly to histamine. There were no
statistically significant effects of histamine in a more limited study of OFF
ganglion cells. The response latencies of ON cells were about 5 ms slower, on
average, when histamine was present. Histamine also reduced the signal to noise
ratio of ON cells, particularly for those cells whose maintained activity was
increased by histamine. Conclusions. A major action of histamine released from
retinopetal axons under dark adapted conditions, when rod signals dominate the
response, is to reduce the sensitivity of ON ganglion cells to light flashes.
These findings may relate to reports that humans are less sensitive to light
stimuli in the scotopic range during the day, when histamine release in the
retina is expected to be maximal.

PMID: 20207974  [PubMed - as supplied by publisher]

8: Invest Ophthalmol Vis Sci. 2010 Mar 5; [Epub ahead of print] 

A comparison of rates of change in neuroretinal rim area and retinal nerve fiber
layer thickness in progressive glaucoma.

Alencar LM, Zangwill LM, Weinreb RN, Bowd C, Sample PA, Girkin CA, Liebmann JM,
Medeiros FA.

Hamilton Glaucoma Center, University of California, San Diego, La Jolla, United
States.

Purpose: To evaluate and compare rates of change in neuroretinal rim area (RA)
and retinal nerve fiber layer thickness (RNFLT) measurements in glaucomatous
patients, glaucoma suspects, and normals followed over time. Methods:
Observational cohort study including patients recruited from two longitudinal
studies (Diagnostic Innovations in Glaucoma Study-DIGS and African Descent and
Evaluation Study-ADAGES), which were followed with standard achromatic perimetry
(SAP), optic disc stereophotographs, confocal scanning laser ophthalmoscopy
(HRT-3) and scanning laser polarimetry (GDx-VCC) imaging. Progression was
determined by the Guided Progression Analysis software for SAP and by masked
assessment of serial optic disc stereophotographs by expert graders. Random
coefficient models were used to evaluate rates of change in average RNFLT and
global RA measurements and their relationship with glaucomatous progression.
Results: At baseline, 194 (31%) eyes were glaucomatous; 347 (55%) were suspects
and 88 (14%) were normals. Forty-six eyes (9%) showed progression by SAP and/or
stereophotographs, during an average follow-up of 3.3 (+/-0.7) years. The
average rate of decline for RNFLT measurements was significantly higher in the
progressing group compared to the non-progressing group (-0.65mum/year vs.
-0.11mum/year, respectively; P<0.001), whereas for RA it was not significantly
different between these groups (-0.0058mm(2)/year vs. -0.0073mm(2)/year,
respectively; P=0.727). The areas under the receiver operating characteristic
curves (ROC) used to discriminate progressing versus non-progressing were 0.811
and 0.507, for the rates of change in RNFLT and RA, respectively (P<0.001).
Conclusion: The ability to discriminate eyes progressing by SAP and/or
stereophotographs from stable eyes was significantly greater for RNFLT compared
to RA measurements.

PMID: 20207973  [PubMed - as supplied by publisher]

9: Invest Ophthalmol Vis Sci. 2010 Mar 5; [Epub ahead of print] 

Influence of Corneal Collagen Crosslinking With Riboflavin and Ultraviolet-A
Irradiation on Excimer Laser Surgery.

Kampik D, Ralla B, Keller S, Hirschberg M, Friedl P, Geerling G.

Department of Ophthalmology, University of Wuerzburg, Wuerzburg, Germany.

Purpose: Riboflavin/UVA crosslinking (CXL) of corneal collagen is a novel method
to stabilize corneal mechanical properties and prevent progression of
keratectasias. The study investigates whether CXL influences ablation rate, flap
thickness and refractive results of Excimer laser procedures ex vivo. Methods:
In enucleated porcine eyes corneal epithelium was removed and CXL performed with
riboflavin 0.1% and UVA radiation (365nm, 3mW/cm(2)) for 30min. Controls
received epithelial abrasion only. Diffusion of riboflavin through the cornea
was assessed using infrared-excited 2-photon microscopy of riboflavin
autofluorescence combined with second harmonic generation of fibrillar collagen.
During phototherapeutic keratectomy corneal thickness was measured by optical
coherence pachymetry. During myopic LASIK flap thickness of microkeratome cuts
was measured and the induced refractive change assessed by Placido topography.
Data were analyzed by Shapiro-Wilk test and Student's t-test. Results:
Multiphoton-imaging showed a rapid (30min) and even distribution of riboflavin
throughout the corneal stroma. No difference in ablation rate was measured in
treated and untreated corneas (p=0.90). Mean flap thickness was increased by 44%
in crosslinked corneas (p<0.01). After myopic LASIK for 4 dpt up to 25 dpt, mean
corneal refractive change was reduced in CXL-treated eyes by 20.1% (p<0.05).
This effect was less pronounced in thinner flaps. Conclusion: CXL reduces the
amount of refractive change after myopic LASIK. While laser ablation rate is
unaffected, CXL results in an increased flap thickness. This study suggests a
need for adjustment of microkeratome and laser parameters for LASIK after CXL
and indirectly endorses the theory of a direct stiffening effect of CXL.

PMID: 20207972  [PubMed - as supplied by publisher]

10: Invest Ophthalmol Vis Sci. 2010 Mar 5; [Epub ahead of print] 

Surface topographies of glaucoma drainage devices and their influence on human
tenon fibroblast adhesion.

Choritz L, Koynov K, Renieri G, Barton K, Pfeiffer N, Thieme H.

BiomaTiCS Research Group, Department of Ophthalmology, University Medical Center
Mainz, Mainz, Germany.

Purpose: This study was performed to investigate the surface topography of
different glaucoma drainage devices, and the effects of surface roughness on
cell adhesion of cultured human tenon fibroblasts. Methods: The surface
topography of four widely used devices (Ahmed FP7, Ahmed S-2, Baerveldt 350,
Molteno S1) was investigated by scanning electron microscopy, roughness was
quantified using white light confocal microscopy. Cells were grown for 72 hours
on the surfaces of implants fixed to standard culture dishes. Cells were
labelled with a fluorescent dye and detected using confocal laser scanning
microscopy, while simultaneously imaging the surface reflectance. Collagen
adsorption was quantified immunologically using fluorescent beads coupled to
secondary antibody. Results: The root-mean-square roughness was 1.5 +/- 0.1
microm (mean +/- SE) for the silicone Ahmed model (FP7) and 1.3 +/- 0.1 microm
for the polypropylene base plate (S-2). The Baerveldt was substantially smoother
with a mean roughness of 0.1 +/- 0.01 microm. The Molteno was the smoothest of
all devices (0.07 +/- 0.01 microm). Cell adhesion was most profound on base
plates with higher surface roughness, markedly less pronounced on the smoother
base plates, and independent of collagen adsorption. Conclusions: This study
shows that the most frequently implanted glaucoma drainage devices are of
markedly different surface topography. Surface roughness appears to correlate
with tenon fibroblast adhesion in vitro and also with the rate of occurrence of
post-implantation hypertensive phase and failure due to fibrous encapsulation.
Surface roughness may thus play a role in triggering excessive fibrovascular
reactions. Smoother base plate surfaces might enhance success rates of these
devices.

PMID: 20207971  [PubMed - as supplied by publisher]

11: Invest Ophthalmol Vis Sci. 2010 Mar 5; [Epub ahead of print] 

Identification of novel substrates for the serine protease HTRA1 in the human
RPE secretome.

An E, Sen S, Park SK, Gordish-Dressman H, Hathout Y.

Institute of Biomedical Science, Program in Biochemistry and Molecular Genetics,
The George Washington University, Washington, United States.

PURPOSE. To define a role of the serine protease HTRA1 in Age-related Macular
Degeneration (AMD) by examining its expression level and identifying its
potential substrates in the context of primary RPE cell extracellular milieu.
METHODS. Primary RPE cell cultures were established from human autopsy eyes and
screened for CFH, ARMS2 and HTRA1 risk genotypes using TaqMan assay. HTRA1
expression in genotyped RPE cells was determined using real time PCR and
quantitative proteomics. Potential HTRA1 substrates were identified by
incubating RPE conditioned media with or without human recombinant HTRA1.
Selectively cleaved proteins were quantified using differential stable isotope
labeling by amino acids in cell culture strategy. RESULTS. HTRA1 mRNA levels
were 3 fold higher in primary RPE cells homozygous for the HTRA1 promoter risk
allele than in RPE cells with the wild type allele. This translated into a 2
fold increase in HTRA1 secretion by RPE cells with the risk genotype. A total of
196 extracellular proteins were identified in the RPE secretome and only 8 were
found selectively cleaved by the human recombinant HTRA1. These include
fibromodulin with 90% cleavage, clusterin (50%), ADAM9 (54%), vitronectin (54%)
and alpha 2 macroglobulin (55%) as well as some cell surface proteins including
talin-1 (21%), fascin (40%) and chloride intracellular channel protein 1 (51%).
CONCLUSIONS. Recombinant HTRA1 cleaves RPE secreted proteins involved in
regulation of the complement pathway (clusterin, vitronectin and fibromodulin)
and of amyloid deposition (clusterin, alpha 2 macroglobulin and ADAM9). These
findings suggest a potential link between HTRA1, complement regulation and
amyloid deposition in AMD pathogenesis.

PMID: 20207970  [PubMed - as supplied by publisher]

12: Invest Ophthalmol Vis Sci. 2010 Mar 5; [Epub ahead of print] 

The Role of TLR4 in Photoreceptor {alpha}A Crystallin Upregulation During Early
EAU.

Saraswathy S, Nguyen AM, Rao NA.

Ophthalmology, Doheny Eye Institute, Los angeles, United States.

PURPOSE: Previous studies indicate that upregulation of alphaA crystallin
prevents photoreceptor mitochondrial oxidative stress mediated apoptosis in EAU.
In this study, the role of TLR4 was investigated in the upregulation of alphaA
crystallin in the retinas of animals with EAU. METHODS: TLR4-/-, iNOS -/-,
TNF-alpha -/-, MyD88 -/-, wild type (WT) control (C57BL/6) animals, and Nude
mice (B6.Cg-Foxn1nu) were immunized with IRBP mixed with complete Freund's
adjuvant; eyes were enucleated on day 7 post immunization. Real-time polymerase
chain reaction was first used to detect upregulated inflammatory cytokines and
alphaA crystallin in retinas with EAU; confirmed with Western blot, and the site
of upregulation was localized by immunohistochemistry. Oxidative stress was
localized using 8-OHdG and TUNEL staining was used to detect apoptosis. RESULTS:
In early EAU, increased expression of TNF-alpha, iNOS, and alphaA crystallin
genes were detected in the retinas of WT mice, whereas such upregulation was
absent in TLR4-deficient mice (P<0.001). alphaA crystallin was not elevated in
MyD88-/-,TNF-alpha -/- and iNOS-/- mice with EAU. Immunostains revealed
TNF-alpha, iNOS, and alphaA crystallin localization in the photoreceptor inner
segments and outer plexiform layer in the WT controls with EAU; but such
staining was absent in TLR4-deficient mice with EAU. 8-OHdG staining showed
oxidative stress in the photoreceptors in WT mice with EAU and there was no
apoptosis. CONCLUSIONS: TLR4 plays an important role in the upregulation of
alphaA crystallin through the interaction of MyD88 and subsequent generation of
TNF-alpha and iNOS in the EAU retina. Such crystallin upregulation may prevent
oxidative stress mediated apoptosis of photoreceptors in uveitis.

PMID: 20207969  [PubMed - as supplied by publisher]

13: Invest Ophthalmol Vis Sci. 2010 Mar 5; [Epub ahead of print] 

Reading strategies in mild to moderate strabismic amblyopia: an eye movement
investigation.

Kanonidou E, Proudlock FA, Gottlob I.

Ophthalmology, University of Leicester, Leicester, United Kingdom.

Purpose. To investigate oculomotor strategies in strabismic amblyopia and
evaluate abnormalities during monocular and binocular reading. Methods. Eye
movements were recorded using a head-mounted infrared video eye-tracker (250Hz,
<0.01 degrees resolution) in twenty strabismic amblyopes (mean age 44.9+/-10.7
years) and twenty normal controls (mean age 42.8+/-10.9 years) whilst silently
reading text paragraphs. Monocular reading comparisons were made between the
amblyopic eye versus non-dominant eye of controls, non-amblyopic eye versus
dominant eye of controls. Binocular reading between the amblyopic and controls
was also compared. Results. Mean reading speed, numbers of progressive and
regressive saccades per line, saccadic amplitude (of progressive saccades) and
fixation duration were estimated. Inter- and intra-subject statistical
comparisons were made. Reading speed was significantly slower in amblyopes
compared to controls during monocular reading with amblyopic (13.094
characters/s v 22.188 characters/s, p<0.0001) and non-amblyopic eyes (16.241
characters/s v 22.349 characters/s, p<0.0001), and binocularly (15.698
characters/s v 23.425 characters/s, p<0.0001). In amblyopes, reading was
significantly slower with the amblyopic eye compared to non-amblyopic eye and
binocular viewing (p<0.05). These differences were associated with significantly
more regressive saccades and longer fixation durations but not with changes in
saccadic amplitudes. Conclusions. In strabismic amblyopia, reading is impaired,
not only under monocular viewing with amblyopic eye, but also with non-amblyopic
eye and binocularly, even though normal visual acuity pertains to the latter two
conditions. The impaired reading performance is associated with differences in
both saccadic and fixational patterns most likely as adaptation strategies to
abnormal sensory experiences such as crowding and suppression.

PMID: 20207968  [PubMed - as supplied by publisher]

14: Invest Ophthalmol Vis Sci. 2010 Mar 5; [Epub ahead of print] 

Gene Expression within the Amacrine Cell Layer of Chicks Following Myopic and
Hyperopic Defocus.

Ashby RS, Feldkaemper MP.

Section of Neurobiology of the Eye, Institute for Ophthalmic Research,
University of Tuebingen, Tuebingen, Germany.

Purpose: Ocular growth is regulated locally by signals produced in the retina.
As the highly heterogeneous nature of the retina may mask important changes in
gene expression during global analysis, this study focused on changes in gene
expression specifically within the amacrine cell layer (ACL), the most likely
generator of growth signals, during optical manipulation of ocular growth.
Method: Chicks were monocularly treated with either -7D (n=6) or +7D (n=6)
lenses for 24hrs. Untreated age-matched chicks served as controls (n=6). Total
RNA from the ACL was isolated from 10microm thick sections, obtained using laser
capture microdissection. Labelled cRNA was prepared from three samples per
condition and hybridized to Affymetrix GeneChip Chicken Genome arrays. Changes
in gene expression were validated using semi-quantitative real-time RT-PCR.
Results: 128 genes were differentially expressed in the ACL of
minus-lens-treated chicks, while plus-lens-treated eyes displayed 58 changes,
24hrs after treatment. The differential expression of glial-cell-line-derived
neurotrophic factor family receptor alpha 1 (GFRA1), general transcription
factor IIH, polypeptide 5 (GTF2H5), Rab22a and the hypothetical protein
LOC425969 were validated in plus lens treated eyes. Similarly, the differential
expression of angiopoietin 2 (ANGPT2), D4, zinc and double PHD fingers, family 3
(DPF3), G protein gamma 13 (GNG13), GRFA1, CD180 Toll-like receptor (CD180), the
cDNA clones (ChEST267a2, ChEST49o10) and the hypothetical protein LOC425969 were
validated in minus lens treated eyes. Conclusion: The selective removal of the
ACL enabled the identification of several novel genes which may form part of the
growth regulatory pathways of the eye.

PMID: 20207967  [PubMed - as supplied by publisher]

15: Invest Ophthalmol Vis Sci. 2010 Mar 5; [Epub ahead of print] 

The Intraflagellar Transport Protein Ift80 is essential for Photoreceptor
Survival in a Zebrafish Model of Jeune Asphyxiating Thoracic Dystrophy.

Hudak LM, Lunt S, Chang CH, Winkler E, Flammer H, Lindsey M, Perkins B.

Texas A&M University, College Station, United States.

Purpose: Jeune's Asphyxiating Thoracic Dystrophy (JATD) is an autosomal
recessive disorder with symptoms of retinal degeneration, kidney cysts, and
chondrodysplasia and results from mutations in the ift80 gene. This study was
conducted to characterize zebrafish lacking ift80 function for photoreceptor
degeneration and defects in ciliogenesis in order to establish zebrafish as a
vertebrate model for visual dysfunction in JATD and to determine if ift80
interacts genetically with Bardet-Biedl Syndrome (BBS) genes. Methods: Zebrafish
were injected with morpholinos (MOs) targeted to the ift80 gene. Retinas were
analyzed by histology, transmission electron microscopy, and
immunohistochemistry. Ear and kidney cilia were analyzed by whole-mount
immunostaining. Intraflagellar Transport (IFT) particle composition was analyzed
by Western blotting. Genetic interactions were tested by co-injection of MOs
against ift80 and bbs4 or bbs8 followed by in situ hybridization. Results:
Zebrafish lacking ift80 function exhibited defects in photoreceptor outer
segment formation, and photoreceptor death. Staining with opsin antibodies
revealed opsin mislocalization in both rods and cones. Ultrastructural analysis
showed abnormal disk stacking and shortened photoreceptor outer segments. The
kinocilia of the ear and motile cilia in the kidney were shorter and reduced in
number. Western blotting revealed a slight increase in the stability of other
IFT proteins. Co-injection of MOs against ift80 and BBS genes led to
convergent-extension defects. Conclusions: Zebrafish lacking ift80 exhibited
defects characteristic of Jeune's Asphyxiating Thoracic Dystrophy. Because the
developing outer segments degenerated, Ift80 could possibly act as a maintenance
factor for the IFT particle.

PMID: 20207966  [PubMed - as supplied by publisher]

16: Invest Ophthalmol Vis Sci. 2010 Mar 5; [Epub ahead of print] 

TIMP 1 neutralizes MMPs activity to inhibit pterygium invasion.

Tsai YY, Chiang CC, Yeh KT, Lee H, Cheng YW.

China Medical University Hospital, Department of Ophthalmology, Taichung,
Taiwan.

Purpose: The migration and invasion of tumor cells correlates with the
interaction between MMP and TIMP. Therefore, the aim of this study was to
determine the role of MMP-9, MMP-10 and TIMPs in pterygium formation and
progression. Methods: MMP-9, MMP-10 and TIMP proteins were studied using
immunohistochemistry on 82 pterygial specimens and 30 normal conjunctivas.
Pterygium epithelial cells (PECs), cultured in a serum-free culture medium, and
siRNA were used to knockdown TIMP gene expression to understand the role of TIMP
in pterygium invasion. Results: Among the 82 pterygial samples, there were 29
specimens (35.4%) positive for MMP-9 expression, 28 positive for MMP-10 (34.1%)
and 59 positive for TIMP1 (72.0%). Staining for MMPs was limited to the
cytoplasm of the epithelial layer. The TIMP staining was detected in the
pterygium epithelium, fibroblasts and corneal epithelium. In the cell model,
cell invasion and migration ability increased in TIMP knockdown PEC cells
compared with the parental control. Conclusion: MMP-9 and MMP-10 may play a role
in pterygium formation and TIMPs may contribute to pterygium invasion
inhibition.

PMID: 20207965  [PubMed - as supplied by publisher]

17: Invest Ophthalmol Vis Sci. 2010 Mar 5; [Epub ahead of print] 

Relationship of Retinal Vascular Tortuosity with Neuroretinal Rim: The Singapore
Malay Eye Study.

Koh VT, Cheung CY, Zheng Y, Wong TY, Wong WL, Aung T.

Singapore Eye Research Institute, Singapore , Singapore.

Purpose: To describe the association of retinal vascular tortuosity, measured
quantitatively, with neuroretinal rim. Methods: A population-based,
cross-sectional study of Malay persons aged 40-80 years residing in Singapore
was conducted. Retinal vascular tortuosity was quantified using a semi-automated
computer-assisted program from retinal fundus photographs, following a
standardized protocol. Optic disc measurements including disc area, rim area and
rim-to-disc area (RDA) ratio were obtained with a confocal scanning laser
ophthalmoscope (Heidelberg Retinal Tomography II). Results: In analyses
adjusting for age, gender, spherical equivalent and retinal vascular caliber,
reduced arteriolar and venular tortuosity were associated with a decrease in
global RDA ratio (P =0.006 and P= 0.001 respectively). When compared to the
arterioles, retinal venular tortuosity demonstrated a stronger association on
RDA ratio. The temporal-inferior region of the neuroretinal rim was most
strongly associated with retinal vascular tortuosity. Conclusion: Straighter
retinal vessels were significantly associated with thinning neuroretinal rim.
These findings may provide additional insights into geometrical retinal vascular
changes seen in early glaucomatous optic neuropathy.

PMID: 20207964  [PubMed - as supplied by publisher]

18: Invest Ophthalmol Vis Sci. 2010 Mar 5; [Epub ahead of print] 

Taz-Tead1 Links Cell-Cell Contact to Zeb1 Expression, Proliferation and
Dedifferentiation in Retinal Pigment Epithelial Cells.

Liu Y, Xin Y, Ye F, Wang W, Lu Q, Kaplan HJ, Dean DC.

Louisville, United States.

PURPOSE. The Hippo signaling pathway imposes the cell contact inhibition which
establishes organ size and tissue topology from Drosophila to mammals. This
pathway regulates activity of the Yap and Taz transcription factors, which link
epithelial-mesenchymal transition (EMT) to cell proliferation. Here, we provide
evidence that Taz and its co-activator Tead1 regulate expression of the EMT
transcription factor Zeb1 to control RPE cell proliferation and differentiation.
METHODS. Real time PCR was used to examine mRNA expression during RPE
dedifferentiation in primary cultures of RPE cells and following knockdown of
Yap and Taz by lentivirus shRNA. Immunofluorescence was used to follow
subcellular localization of proteins in cells. Chromatin immunoprecipitation was
used to detect Taz at the Zeb1 promoter in vivo. RESULTS. Zeb1 is overexpressed
during RPE dedifferentiation leading to cell proliferation, EMT and repression
of the RPE specification transcription factor gene Mitf. Taz-TEAD1 translocation
to the nucleus coincides with loss of cell-cell contact and with onset of Zeb1
expression in the nucleus. shRNA knockdown of Taz prevented overexpression of
Zeb1 and in turn it prevented proliferation, repression of Mitf and Mitf target
genes and EMT when RPE cells were placed in primary culture. Taz binds to the
Zeb1 promoter in vivo, suggesting that it directly induces Zeb1 transcription.
CONCLUSION. These results provide evidence of a molecular mechanism linking
cell-cell contact to cell proliferation and dedifferentiation in RPE cells.

PMID: 20207963  [PubMed - as supplied by publisher]

19: Invest Ophthalmol Vis Sci. 2010 Mar 5; [Epub ahead of print] 

Monitoring Vigilance During Perimetry with Pupillography.

Henson DB, Emuh T.

School of Medicine, University of Manchester, Manchester, United Kingdom.

Purpose: To report and present data on a method for monitoring patient vigilance
during a visual field test using pupillometry. Methods: Pupil diameter was
recorded at 60Hz using a VET system (CRS, Cambridge, UK) from 13 patients
attending the glaucoma outpatient clinics at Manchester Royal Eye Hospital.
Patients were instructed to fixate a central target and to press a response
button when they saw a stimulus that was randomly presented either 5 degrees to
the left or right of fixation. A repetitive up/down bracketing strategy was used
(1dB steps, 2 s inter stimulus interval, 10 min duration) at these 2 locations.
Wavelet analysis (Wavelet Toolbox v 4.1, The MathWorks, Mass, USA) was used to
extract a de-noised measure of the pupil diameter and the amplitude of any
pupillary fatigue waves. The relationship between the probability of seeing a
stimulus and these 2 components of the pupil response were investigated.
Results: Good pupil data was obtained from 12 patients, most (8/12) showed a
gradual miosis and periods of pupillary fatigue waves during the recorded
session. Pupillary fatigue waves became more evident with test duration and the
probability of seeing a stimulus was higher when the pupil was dilated (p<0.001)
and the amplitude of the papillary fatigue waves was low (p<0.001). Conclusions:
Pupil miosis and fatigue wave amplitude are related to vigilance in patients
undertaking a perimetric-like test. Pupillography can be used to investigate
vigilance and how this contributes to perimetric variability.

PMID: 20207962  [PubMed - as supplied by publisher]

20: Invest Ophthalmol Vis Sci. 2010 Mar 5; [Epub ahead of print] 

Normal physiological and pathophysiological effects of trypan blue on the retina
of albino rabbits.

Heilweil G, Komarowska I, Zemel E, Loewenstein A, Perlman I.

Ophthalmology, Tel Aviv Medical Center, Tel Aviv, Israel.

Purpose: To determine whether intravitreal injection of trypan blue is toxic to
the retina of albino rabbits. Methods: Sixteen albino rabbits were studied for
the effects of intravitreal trypan blue; 8 with 0.06% solution and 8 with 0.15%
solution. Saline was injected into the fellow control eye of all rabbits. The
electroretinogram and visual evoked potentials were recorded from each rabbit at
different time intervals after injection. The rabbits were sacrificed at the
termination of the follow-up period, and their retinas were prepared for
histological examination under light microscopy. Results: In all rabbits,
short-term follow-up, showed significant reduction of the ERG responses in the
experimental eye with the b-wave more affected compared to the a-wave. Partial
to complete recovery was observed during follow-up, and after 4 weeks negligible
ERG deficit was observed in the rabbits treated with the 0.06% trypan blue,
while significant ERG deficit was measured in rabbits tested by the 0.15% trypan
blue. No difference in the flash VEP responses between experimental and control
eyes were found in all rabbits. Light microscopy showed no significant
histological effects in the retinas exposed to the 0.06% solution. Marked
disorganization of all retinal layers was observed in areas close to the site of
injection in the rabbits injected with the 0.15% solution. Conclusions: Trypan
blue exerts transient physiological effects on the distal retina of the rabbit,
but in concentration of 0.15% it can induce permanent toxic effects. Therefore,
caution should be used when using this dye in vitreoretinal surgery.

PMID: 20207961  [PubMed - as supplied by publisher]

21: Invest Ophthalmol Vis Sci. 2010 Mar 5; [Epub ahead of print] 

The Shape of Posterior Corneal Surface in Normal, Post-LASIK, and Post-Epi-LASIK
Eyes.

Zhang L, Wang Y.

Refractive Surgery Center, Tianjin Eye Hospital & Eye Institute, Tianjin Medical
University, Tianjin, China.

PURPOSE: To evaluate the shape of posterior corneal surface in normal myopic and
myopic astigmatism eyes and the changes following LASIK and Epi-LASIK. METHODS:
A total of 152 eyes were included in this study. The posterior corneal elevation
was measured with Scheimpflug imaging (Pentacam, Oculus) before LASIK or
Epi-LASIK and at 1 and 6 months after the surgeries along the 4 optical zones
(center, 2-mm, 4-mm, and 6-mm diameters) as a function of the meridian. RESULTS:
For normal eyes, the heights were lower in the vertical meridian than in the
horizontal meridian, and were also lower in the superior hemisphere than in the
inferior hemisphere. In post-LASIK eyes, almost all regions protruded 1 month
after surgery except for the 6-mm diameter, where it exhibited a slight but not
significant (p=0.731) backward displacement. The various elevations returned to
original levels 6 months after LASIK. In the post-Epi-LASIK group, there was a
significant backward displacement at the center and 2-mm regions
postoperatively. Moreover, there was no shift at the 4-mm diameter, and the 6-mm
showed a progressive forward shift. CONCLUSIONS: The shape of normal posterior
corneal surface exhibited obvious regional disparities and radial asymmetry. The
displacement following LASIK was observed as time-dependent changes that
protruded at an early stage but then returned to original levels 6 months after
surgery. On the other hand, the displacement following Epi-LASIK showed as
region-dependent changes that could be divided into central and peripheral
parts, which displayed backward and forward shift trends, respectively.

PMID: 20207960  [PubMed - as supplied by publisher]

22: Invest Ophthalmol Vis Sci. 2010 Mar 5; [Epub ahead of print] 

A novel p40-independent function of IL-12p35 is required for progression and
maintenance of herpes stromal keratitis.

Frank GM, Divito S, Maker DM, Xu M, Hendricks RL.

Ophthalmology, University of Pittsburgh, Pittsburgh, United States.

Purpose: Interleukin (IL)-12p40 can couple with IL-12p35 or p19 chains to form
the molecules IL-12p70 and IL-23, respectively that promote TH1 cytokine
responses. IL-12p35 can bind to EBI3 to form an anti-inflammatory molecule
IL-p35, but a proinflammatory function of IL-12p35 independent of IL-12p40 has
not been described. Here we demonstrate such a function in a mouse model of
herpes stromal keratitis (HSK), a CD4+ TH1 cell dependent corneal inflammation.
Methods: Corneas of wild type (WT), IL-12p40-/-, IL-12p35-/-, and
IL-12p35-/-p40-/- (double knockout) mice were infected with the RE strain of
HSV-1, and HSK was monitored based on corneal opacity, neovascularization,
leukocytic infiltrate, and cytokine/chemokine levels. Results: All mouse strains
developed moderate HSK by 11 days post infection (dpi). However, from 11-21 dpi
HSK progressed in WT and IL-12p40-/- mice, but regressed in IL-12p35-/-, and
IL-12p35-/-p40-/- mice. HSK regression was characterized by reductions in
neutrophils and CD4+ T cells and attenuation of blood vessels, which was
associated with reduced levels of the chemokines KC (CXCL3), Mip-2 (CXCL2), and
MCP-1 (CCL2) and the angiogenic factor vascular endothelial growth factor
(VEGF). Conclusion: HSK development does not require IL-12p40 and is thus
independent of IL-12p70 and IL-23. However, late HSK progression does require a
previously unrecognized IL-12p40-independent, proinflammatory function of
IL-12p35.

PMID: 20207959  [PubMed - as supplied by publisher]

23: Invest Ophthalmol Vis Sci. 2010 Mar 5; [Epub ahead of print] 

Measurement of ophthalmodynamometric pressure using Vented Gas Forced Infusion
system during pars plana vitrectomy.

Okamoto F, Sugiura Y, Okamoto Y, Hasegawa Y, Hiraoka T, Oshika T.

Department of Ophthalmology, University of Tsukuba, Tukuba, Japan.

Purpose: To measure ophthalmodynamometric pressure (ODP) using Vented Gas Forced
Infusion (VGFI) system during vitrectomy in patients with various vitreoretinal
disorders and to investigate factors related to ODP. Methods: This study
included 169 eyes of 169 patients undergoing pars plana vitrectomy. After core
vitrectomy, the intraocular pressure was gradually raised using VGFI system.
When the central retinal artery or its branches on the optic nerve head showed
pulsations, the pressure was recorded as ODP. Diastolic blood pressure (DBP) and
systolic blood pressure (DBP) were measured at the time of ODP measurement.
Multiple regression analysis was performed to investigate the relationship
between ODP and various explanatory variables; DBP, SBP, age, presence of
diabetic mellitus (DM) and hypertension (HT), body mass index, and serum total
cholesterol. Results: ODP was 66.9 +/- 12.5 mmHg (range 15.5 - 103.7 mmHg). ODP
significantly correlated with DBP (r= 0.60, p < 0.0001), but not with SBP (r =
0.12, p = 0.12). ODP in DM patients including proliferative diabetic retinopathy
and diabetic macular edema was lower than that in non-DM patients, while DBP was
not significantly different between two groups. Similar results were obtained in
HT patients. Multiple regression analysis revealed that ODP had a significant
correlation with DBP (p < 0.0001), presence of DM (p = 0.02) and presence of HT
(p = 0.03). Conclusions: We developed a new method to determine ODP using VGFI
system. ODP was significantly associated with DBP and was lower in patients with
DM and HT.

PMID: 20207958  [PubMed - as supplied by publisher]

24: Invest Ophthalmol Vis Sci. 2010 Mar 5; [Epub ahead of print] 

Neuronal driven angiogenesis: The role of NGF in retinal neovascularization in
an oxygen- induced retinopathy model.

Liu X, Wang D, Liu Y, Luo Y, Ma W, Xiao W, Yu Q.

State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center,Sun Yat-sen
University, Guangzhou, China.

Purpose: To evaluate the role of nerve growth factor (NGF) in retinal
neovascularization in an oxygen-induced retinopathy (OIR) model. Materials and
Methods: The OIR model was established in C57BL/6J mice. NGF mRNA expression in
retina was measured by Quantitative Real-Time PCR. NGF expression in protein
level was evaluated by ELISA and immunostaining with NGF antibody. The effects
of NGF on retinal neovascularization were evaluated by intravitreal injections
of exogenous NGF and TrkA receptor inhibitor K252a, respectively, in an OIR
model. Retinal neovascularization was measured by counting neovascular cell
nuclei above the internal limiting membrane and by image quantification analysis
in flat-mounted retinas perfused with fluorescein dextran. Results: NGF mRNA in
retina had significantly high expression at postnatal day 17 (P17) in the OIR
model compared to the normally developing mice. Similarly, ELISA and
immunostaining assay showed significantly increased NGF expression in retina at
P17 in OIR mice, but no significant differences at P12 or P24 compared to normal
controls. Exogenous NGF intraocular injection enhanced angiogenesis in the
retina in the OIR model; however, injection with K252a, a high-affinity trkA
receptor inhibitor, significantly decreased retinal neovascularization compared
to that seen in the controls. Conclusion: NGF contributed to retinal
neovascularization in the OIR model. Intravitreal injection with K252a, the trkA
receptor inhibitor, reduced neovascularization, showing the potential
therapeutic efficacy of NGF receptor inhibitor in OIR mice.

PMID: 20207957  [PubMed - as supplied by publisher]

25: Invest Ophthalmol Vis Sci. 2010 Mar;51(3):1397-400. 

An in vivo confocal microscopy and impression cytology analysis of goblet cells
in patients with chemical burns.

Le QH, Wang WT, Hong JX, Sun XH, Zheng TY, Zhu WQ, Xu JJ.

Department of Ophthalmology, Eye & ENT Hospital of Fudan University, Shanghai,
China.

PURPOSE: To evaluate goblet cell density (GCD) on conjunctiva and cornea in
patients with ocular chemical burns by in vivo laser scanning confocal
microscopy (LSCM) and impression cytology (IC) and to explore the correlation
between two methods. METHODS: Fifty-four patients (58 eyes) with chemical burn
were enrolled in the study. LSCM was applied to identify the goblet cells on
conjunctiva and cornea under in vivo conditions, and GCD was analyzed with the
customized software. Impression cytology was then performed, and the biopsy
specimens were stained to visualize goblet cells in vitro and to measure the
density. Statistical software was used to analyze the correlation between GCD
taken by two methods. RESULTS: Conjunctival goblet cells could be discriminated
in 55 eyes and 57 eyes by in vivo LSCM and IC. They could be identified on the
cornea in nine eyes and eight eyes by two methods. The positive rate of two
methods had no significant difference. GCDs on conjunctiva measured by in vivo
LSCM and IC were 136 +/- 79 cells/mm(2) and 121 +/- 66 cells/mm(2). Median GCDs
on cornea detected by two methods were 30 cells/mm(2) and 23 cells/mm(2),
respectively. A significant positive correlation was found between the GCDs on
conjunctiva measured by these two methods as well as the GCDs on cornea.
CONCLUSIONS: GCD decreased in patients with chemical burns. A positive
correlation was found between GCD measured by in vivo LSCM and IC after chemical
burns. In vivo LSCM was a promising device to study goblet cells in vivo under
pathologic conditions.

Publication Types:
    Research Support, Non-U.S. Gov't

PMID: 20185840  [PubMed - in process]

26: Invest Ophthalmol Vis Sci. 2010 Mar;51(3):1282-8. 

Deactivation mechanisms of rod phototransduction: the Cogan lecture.

Burns ME.

Department of Ophthalmology and Vision Science and Center for Neuroscience,
University of California, Davis, California, USA

The absorption of photons in rods and cones of the retina activate homologous
biochemical signaling cascades that lead to the electrical changes that subserve
the first steps in vision. Persistent activity of the cascade interferes with
the ability of the photoreceptor to signal the absorption of subsequent photons,
ultimately limiting the photoreceptor's sensitivity and temporal resolution.
This article summarizes recent work on transgenic and knockout mouse rods that
has revealed the deactivation mechanisms essential for normal response recovery
and how each of these processes contributes to the overall time course of the
flash response of rods.

PMID: 20185839  [PubMed - in process]

27: Invest Ophthalmol Vis Sci. 2010 Mar;51(3):1275-81. 

Age-related macular degeneration: the molecular link between oxidative damage,
tissue-specific inflammation and outer retinal disease: the Proctor lecture.

Hollyfield JG.

Department of Ophthalmology, Cole Eye Institute, Cleveland Clinic Lerner College
of Medicine, Cleveland, Ohio 44195, USA. hollyfj@ccf.org

PMID: 20185837  [PubMed - in process]

28: Invest Ophthalmol Vis Sci. 2010 Mar;51(3):1263-74. 

Synaptic organization of the vertebrate retina: general principles and
species-specific variations: the Friedenwald lecture.

Wu SM.

Cullen Eye Institute, Baylor College of Medicine, Houston, Texas, USA.

Publication Types:
    Research Support, N.I.H., Extramural
    Research Support, Non-U.S. Gov't

PMID: 20185835  [PubMed - in process]

29: Invest Ophthalmol Vis Sci. 2010 Mar;51(3):1261-2. 

Remembering Steven M. Podos, MD, 1937-2009.

Candia OA, Kaufman PL.

PMID: 20185833  [PubMed - in process]

30: Invest Ophthalmol Vis Sci. 2010 Feb 24; [Epub ahead of print] 

Screening for Meibomian Gland Disease: Its Relation to Dry Eye Subtypes and
Symptoms in a Tertiary Referral Clinic in Singapore.

Tong L, Chaurasia SS, Mehta JS, Beuerman RW.

Cornea and external eye disease, Singapore National Eye Center, Singapore,
Singapore.

Background/aims: To study screening methods and associated factors of Meibomian
gland disease and dry eye subtypes in a specialized eye clinic in Singapore.
Methods: This cross-sectional study involved 200 patients in a dry eye clinic
and the outcome measures evaluated are Dysfunctional Tear Syndrome (DTS) level,
Meibomian Gland Disease grade, Schirmer's test (ST), fluorescein tear break up
time (TBUT), corneal fluorescein staining grade, and irritative eye symptoms.
Results: The Meibomian gland screening grade was associated with TBUT (p=0.007),
especially in the upper eyelid, and correlated to reading difficulty (p=0.007),
and reversibility of symptomatic blurring with lubricants (p=0.006). Abnormal ST
was associated with early morning discomfort (p=0.001) and reduced TBUT was
linked to discomfort in windy conditions (p<0.001). In all patients examined,
evaporative dry eye (58%) was most common, followed by mixed evaporative and
aqueous tear deficiency (30.5%) types. Fluorescein staining in the central and
inferior cornea was most severe in the mixed type. Conclusions: In dry eye
patients, screening for Meibomian gland disease based on anteriorisation of
Marx's line may predict decrease in TBUT and difficulties performing certain
visual-function related activities. This facilitates better understanding of the
Meibomian gland's contribution to multi-factorial dry eye syndrome, apart from
routine conventional tests performed in clinics.

PMID: 20181848  [PubMed - as supplied by publisher]