All spectral-domain optical coherence tomographers, despite different resolution and acquisition rates, have the same ability to detect glaucoma, says a team of U.S. and Brazilian researchers. Their study compared the diagnostic accuracies of retinal nerve fiber layer thickness measurements obtained with the Spectralis (Heidelberg Engineering), Cirrus (Carl Zeiss Meditec), and RTVue (Optovue). Researchers evaluated a total of 233 eyes (107 healthy, 126 glaucomatous) of 149 participants from the longitudinal Diagnostic Innovations in Glaucoma Study (DIGS) and from the African Descent and Glaucoma Evaluation Study (ADAGES). All participants underwent RNFLthickness imaging with the Spectralis, Cirrus, and RTVue devices in the same visit. Receiver operating characteristic (ROC) curves adjusted for age and race were obtained for quadrants (superior, nasal, inferior, temporal) and global RNFLthickness for all instruments. Areas under ROC (AUC) and sensitivities at fixed specificities (80 percent and 95 percent) were calculated and compared as the main outcome measure.
The researchers found that the RNFLthickness parameter with the largest
AUCs was the superior quadrant for the Spectralis (0.88) and the global
RNFL thickness for the Cirrus (0.88) and the RTVue (0.87). The pairwise
comparison among the ROC curves showed no statistical difference for all
parameters except for the nasal quadrant, which had significantly
larger AUC in the Spectralis and RTVue compared with the Cirrus
(p<0.03 for both comparisons). There were no significant differences
in sensitivities among the best parameters from each instrument
(p>0.05). The superior quadrant thickness measured with the Spectralis had
sensitivity of 81.9 percent at a fixed specificity of 80 percent and 70
percent at a fixed specificity of 95 percent. The global thickness
measured by the Cirrus had a sensitivity of 80.3 percent at a fixed
specificity of 80 percent and 65.6 percent at a fixed specifi city of 95
percent. For the RTVue, the global thickness had a sensitivity of 77.9
percent at a fixed specificity of 80 percent, and 62.1 percent at a
fixed specificity of 95 percent.
Leite MT, Rao HL, Zangwill LM, et al.
Simultaneous and Sequential Cataract Surgeries Fairly Equal
study conducted at the Helsinki University Eye Hospital in Finland
assessed clinical and economic outcomes for simultaneous and sequential
bilateral cataract surgery.
The first part of the study, designed as a clinical trial, showed that
refractive outcomes, rates of complications, and patient-rated
satisfaction were similar whether bilateral cataract surgery was
performed simultaneously or sequentially. Consecutive patients
scheduled for bilateral cataract surgery were enrolled based on
appropriate inclusion criteria and randomized to be operated on in one
session (study group) or sequentially (control group) four to six weeks
Four hundred ninety-one (94.4 percent) of the 520 patients completed the
study. Of the eyes, 493 (247 patients) had bilateral surgery in one
session and 506 (257 patients) in separate sessions. In the study
group, 240 patients (96 percent) were treated per protocol. In the
control group, 250 patients (97.3 percent) were treated per protocol. The refraction was within ±0.50 D of the target in 67.2 percent of eyes
in the study group and 69.2 percent of eyes in the control group, and
within ±1 D in 91.0 percent and 90.3 percent, respectively (p=0.92). The
only complication that affected postoperative visual acuity was chronic
cystoid macular edema, which occurred in one eye in the study group
(0.2 percent) and in two eyes (0.4 percent) of one patient in the
control group (p=0.57). Ninety-five percent of patients in both groups
reported being very satisfied with surgery.
Results from the second part of the study suggested that sequential and
simultaneous bilateral cataract surgery provided comparable clinical
outcomes with substantial savings in health-care and
non-health-carerelated costs. Researchers estimated the effects of the
procedures from data in a study in which patients were randomized to
have bilateral cataract surgery on the same day (study group) or
sequentially (control group).
The main clinical outcomes were corrected distance visual acuity,
refraction, complications, Visual Function Index-7 (VF-7) scores and
patient- rated satisfaction with vision. Health-care costs of surgeries
and preoperative and postoperative visits were estimated, including the
cost of staff, equipment, material, floor space, overhead and
complications.The data were obtained from staff measurements,
questionnaires, internal hospital records and
accountancy. Non-health-care costs of travel, home care and time were
estimated based on questionnaires from a random subset of patients.
The main economic outcome measures were cost per VF-7 score unit change
and cost per patient in simultaneous versus sequential surgery. The study
comprised 520 patients (241 patients included non-healthcare and time
cost analyses). Surgical outcomes and patient satisfaction were similar
in both groups. Simultaneous cataract surgery saved 449 per patient in
health-care costs and 739 when travel and paid homecare costs were
included. The savings added up to 849 per patient when the cost of lost
working time was included.
J Cataract Refract Surg 2011;37:992-1002.
Sarikkola AU, Uusitalo R, Hellstedt T, et al.
J Cataract Refract Surg 2011;37:1003-8.
Leivo T, Sarikkola AU, Uusitalo RJ, et al.
Higher IOP Common After Intravitreal Injection
pressure, sustained or unsustained, after intravitreal injection is not
uncommon, suggests new research from the University of California Los
In an attempt to investigate elevated intraocular pressures (defined as a
measurement >25 mmHg at a follow-up visit) after an intravitreal
injection of anti-vascular endothelial growth factor agents for
age-related macular degeneration, the researchers did a retrospective
review of medical records for 27 patients (155 eyes) that received an
intravitreal injection of anti-vascular endothelial growth factor agents
(bevacizumab, ranibizumab or pegaptanib) ranging from one to 39
injections for more than a period of 30 to 1,759 days.
Results showed that, among this population, 12 patients (14 eyes; 9.4
percent) developed elevated IOP 25 mmHg. Of these, seven patients (5. 5
percent) developed sustained elevated IOP (IOP >25 mmHg on two
separate visits requiring glaucoma medication or surgery), of which
eight eyes required topical medications and one eye underwent glaucoma
Mean IOP of injected eyes receiving intravitreal injection was 15.2 ±2.4
mmHg, and the mean IOP was 14. 9 ±2.6 mmHg for noninjected eyes. Among
eyes that had elevated IOPs, there was no association with injection
frequency, number of injections or anti-vascular endothelial growth
factor agent used.
Choi D, Ortube MC, McCannel C, et al.
Low-dose Triamcinolone Safe In Treating Vitreoretinopathy
researchers find low-dose (2 mg) triamcinolone acetonide intravitreal
injection as an adjunct to vitrectomy and silicone oil tamponade in
treating proliferative vitreoretinopathy (grade C or D) to be effective
and safe. Researchers from the Chinese University of Hong Kong reviewed
a retrospective interventional case series to evaluate the midterm
anatomical and functional outcomes of intravitreal injection of low-dose
triamcinolone acetonide in silicone oil-filled eyes as an adjunctive
Patients with proliferative vitreoretinopathy grade C or D received pars
plana vitrectomy combined with silicone oil tamponade and intravitreal
injection of 2 mg of triamcinolone acetonide in the first stage and
silicone oil removal in the second stage. Primary outcome measures were
retinal reattachment rate and best-corrected visual acuity.
Thirty-seven eyes from 37 patients were included in this study. The mean
follow-up duration was 22. 9 ±9.6 months. Retina was reattached in 36
(97.3 percent) eyes at the last visit. The mean best-corrected visual
acuity was 1.76 ±0.56 logMAR at baseline, which improved to 0.87 ±0.60
logMAR at the last visit (p<0.001). Best-corrected visual acuity
increased in 31 (83.8 percent) eyes, remained unchanged in five(13. 5
percent) eyes, and decreased in one (2.7 percent) eye at last visit
compared with baseline.
Chen W, Chen H, Hou P, et al.
Post-PK Suture Infections Less Common Than Reported?
The rate of suture-related infections after penetrating keratoplasty may
be lower than previously reported, suggests new research from the Cole
Eye Institute in Cleveland. Researchers reporting on the incidence,
occurrence rate and characteristics of suture-related infections after
PK evaluated patients who underwent PK at the institute between January
2002 and July 2006. Those patients were cross-referenced with patients
diagnosed with corneal infections between January 2002 and July 2007. All
patient charts were reviewed retrospectively for occurrence of
suturerelated infections, duration of follow-up and clinical
Of the 487 Pks performed in 412 patients, 22 eyes of 22 patients
developed postoperative corneal infections. Of these, five eyes were
identified as having suture-related graft infections, yielding an
occurrence rate of 1 percent. The average followup was 3.46 years per
PK, yielding an incidence of 2.96 infections per 1,000 PK-years. The
mean interval from surgery to infection was eight months (range: three
to 23 months).
All culprit sutures were in the interpalpebral zone. No patients were
using topical antibiotics at the time of infection, and all patients
were using topical corticosteroid drops. Cultured organisms included
Staphylococcus aureus (three cases), coagulase-negative Staphylococcus
(one case) and S. viridans (one case).
In two patients with isolated corneal involvement, topical moxifloxacin
was initiated, and the patients responded favorably. In three patients
with corneal infection and an associated hypopyon or endophthalmitis,
vitreous biopsy, intravitreal injections of antibiotics and fortified
topical antibiotics were used. One patient required a repeat PK as a
result of the infection. Two eyes eventually became phthisical.
Hood CT, Lee BJ, Jeng BH.
Ortho-K Lenses May Affect Epithelium After Short Wear
New research shows that overnight
orthokeratology lenses for myopia induce significant structural and
optical changes, particularly in the central epithelium, after 15 days
or one month of wear.
In a prospective, single-center, longitudinal trial to examine the
morphological and biometric corneal changes produced by ortho-K lenses,
researchers at University School of Optics in Madrid reviewed 27 right
eyes of 27 subjects (group 1) with low to moderate myopia who wore
ortho-K lenses for one month. Ten right eyes of 10 subjects (group 2)
with emmetropia to low myopia who did not wear any type of contact lens
served as controls. Corneal morphometric measurements were obtained in
vivo using a confocal microscope to examine the central and
midperipheral cornea. Thickness measurements in the peripheral cornea
were obtained by optical coherence tomography. Changes in visual acuity,
refractive error and corneal topography were also analyzed.
No significant changes in either endothelial cell or stromal cell
density were observed after one month of ortho-K. Basal epithelial
cells were, however, significantly reduced (p<0.01), and epithelial
wing and superficial cells showed enhanced visibility (p<0.05).
Superficial cells increased in height and width, the width increase
after one month being significant (p<0.01). Epithelial thickness was
significantly reduced in the central cornea and 2 mm around the center.
Corneal pachymetry increased significantly in the band from 5 to 10 mm
from the corneal apex (p<0.01).
The researchers concluded that the central corneal epithelium responds
to ortho-K wear by undergoing significant epithelial cell shape and size
alterations with no effects, however, on the cells of the corneal
endothelium or the corneal stroma. Peripheral corneal thickness
increased with respect to baseline values.
These findings suggest that the corneal epithelium is the principal
structure affected by the mechanical forces exerted by the ortho-K
lenses, the group concludes.
Nieto-Bona A, González-Mesa A, Nieto-Bona MP, et al.