Category: Peer-reviewed

Reduced Cerebrovascular Reactivity in Posterior Cerebral Arteries in Patients with Primary Open-Angle Glaucoma – Corrected Proof

Purpose: To evaluate the hemodynamics and vasoreactivity in the posterior cerebral artery (PCA) in patients with primary open-angle glaucoma (POAG).Design: Case-control study.Participants: Thirteen POAG patients (age range, 40–60 years) with marked visual field loss (mean deviation [MD], <−6 dB); a preserved, mostly normal, central visual field of at least 5°; and best-corrected visual acuity of at least 20/40 formed the study group. Exclusion criterion was presence or history of any systemic disorder including cardiovascular diseases. The control group consisted of 12 healthy subjects matched for age and sex with the study group.Methods: Applying transcranial Doppler sonography, we measured hemodynamic parameters in both PCAs at baseline, under monocular reversing checkerboard stimulation, and under hyperventilation. The eye with more marked visual field loss was selected in glaucoma patients, whereas in controls, the tested eye was chosen randomly. Ipsilateral and contralateral PCA were defined according to the tested eye.Main Outcome Measures: Peak systolic velocity (PSV), end-diastolic velocity, mean velocity (MV), MV change percentage (MV%), resistivity index (RI), pulsatility index (PI).Results: At baseline, RI (0.55±0.04 vs. 0.52±0.03; P = 0.04) and PI (0.88±0.11 vs. 0.80±0.07; P = 0.04) in the ipsilateral PCA were significantly higher in glaucoma patients than in controls. During checkerboard stimulation, MV% in both PCAs were significantly smaller in the glaucoma group than in controls (19.7±7.2% and 19.0±8.3% vs. 30.7±7.9% and 27.5±9.0%, respectively; P = 0.001 and 0.02, respectively). During hyperventilation, glaucoma patients showed significantly lower MV% in the contralateral PCA than control subjects (−39.8±9.6% versus −47.4±7.0%; P = 0.03). Perimetric pattern standard deviation (PSD) in the tested eye was correlated significantly with RI and PI of the ipsilateral PCA during checkerboard stimulation (P = 0.003, r = −0.76; and P = 0.002, r = −0.76). The MV% of contralateral PCA was correlated inversely with PSD in the fellow eye (P = 0.02, r = −0.64). The difference in MV% between both PCAs was correlated positively with the difference in MD between 2 eyes (P = 0.003, r = 0.75). Under hyperventilation, PSV in the contralateral PCA was correlated negatively with the PSD in the fellow eye (P = 0.03, r = −0.60).Conclusions: Vascular insufficiency in the PCAs may be associated with POAG. Changes in the vasoreactivity of PCAs to central visual stimulation may precede marked central visual field loss.Financial Disclosure(s): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Case Reviews in Ophthalmology

Media Type: Textbook Synopsis: The diagnosis of medical conditions and the management of these conditions is the basis of all fields of clinical medicine, and the field of Ophthalmology is no exception. Case Reviews in Ophthalmology does an excellent…

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We appreciate the interest and comments expressed by Dr Goldberg concerning our article and for bringing this interesting point of limbal palisades of Vogt slit-lamp photography to the readers’ attention. As correctly pointed out, the patient’s complia…

Vitrectomy With or Without Preoperative Intravitreal Bevacizumab for Proliferative Diabetic Retinopathy: A Meta-Analysis of Randomized Controlled Trials

Purpose: To compare safety and functional outcomes of vitrectomy with or without preoperative intravitreal bevacizumab (IVB) for proliferative diabetic retinopathy (PDR).Design: A meta-analysis of randomized controlled trials.Methods: PubMed, Medline, EMBASE, and Cochrane Controlled Trials Register were searched to identify potentially relevant randomized controlled trials. A total of 394 participants with 414 eyes in 8 trials were analyzed using RevMan 5.1 software. The primary measures included intraoperative bleeding, total surgical time, and early and late recurrent hemorrhage.Results: Vitrectomy with IVB pretreatment achieved shorter overall surgical time (mean difference = −26.89 minutes, 95% confidence interval [CI] −31.38 to −22.39, P < .00001) and smaller number of endodiathermy applications (mean difference = −3.46, 95% CI −6.43 to −0.49, P = .02) compared to vitrectomy alone. The IVB group was also associated with less intraoperative bleeding (odds ratio [OR] = 0.10; 95% CI 0.02 to 0.46; P = .003) and recurrent vitreous hemorrhage within first month (OR = 0.35; 95% CI 0.21 to 0.58; P < .0001), but the proportion of recurrent vitreous hemorrhage after the first month was comparable between both groups. There were no significant differences in other complication rates between the 2 groups, with the exception of iatrogenic retinal break, which was more likely with the vitrectomy-alone group (OR = 0.27, 95% CI 0.12 to 0.63, P = .003). Results were robust to sensitivity analyses.Conclusions: Adjuvant intravitreal injection of bevacizumab prior to vitrectomy in PDR patients significantly eased the procedure, diminished intraoperative complications, and reduced early postoperative hemorrhage without increasing the risk of vision-threatening complications. Further trials should determine the optimal interval and dosage for IVB injection.

Color Atlas & Synopsis of Clinical Ophthalmology, Wills Eye Institute, Cornea, Second Edition

Media Type: Textbook Synopsis: Recognizing signs and symptoms of anterior segment disorders is essential in making accurate diagnosis and rendering appropriate treatment. The Color Atlas & Synopsis of Clinical Ophthalmology provides a comprehensive review of over 150 clinical entities involving conjunctiva, cornea, sclera, and iris. Each condition is succinctly summarized including etiology, symptoms, signs, diagnostic evaluation, differential diagnosis, treatment, and prognosis. Clinical photographs accompany each entity. Traumatic injuries as well as surgical complications are also included. This second edition builds on the success of the first edition, but expands to include new management options as well as new surgical techniques and complications.

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I read with great interest Zabalza and associates’ commentary in response to my article and Dr Ryan’s accompanying editorial. I thank the authors for sharing their experience in Spain and Portugal through the Retina 1 Project, and for contributing to o…

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We thank Dr Kocatürk and associates for their thoughtful correspondence regarding our manuscript. First, inflammation plays a critical role in the development of corneal neovascularization; therefore, inflammation received careful consideration in t…

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The term retinal vasoproliferative tumor (VPT, or what we call reactive retinal astrocytic tumor) was initially applied to the entity under discussion by J. Shields, and we can appreciate the Shieldses’ ongoing attachment to it. We do not wish, however…

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We appreciate the interest of Heindl et al in our recent article in which we report the presence of ciliary body lymphatics in all melanoma eye cases studied. Our group was the first to identify lymphatics in the ciliary body of the normal human eye. T…

Scheimpflug Corneal Power Measurements for Intraocular Lens Power Calculation in Cataract Surgery – Corrected Proof

Purpose: To compare the keratometric (K) readings from the Pentacam-HR (High Resolution) unit with the automated K values from the IOLMaster keratometer (KIOLM), and to evaluate them in the commonly used intraocular lens (IOL) power calculation formulas for routine cataract surgery.Design: Prospective, comparative observational study.Methods: setting: Private practice, Lynwood, California. study population: Fifty cataractous eyes scheduled for surgery between July and August 2012. observation procedure: The K readings from the Pentacam-HR unit taken at the 2-, 3-, 4-, and 5-mm zones and the 2-, 3-, 4-, and 5-mm rings, respectively, from 3 different maps: sagittal corneal front (KF), true net power (KTNP), and total refractive power (KRP) are compared with KIOLM. IOL power calculations were performed with each of the 25 sets of K readings. main outcome measures: The IOL prediction median absolute error (MedAE) obtained with each measurement.Results: KF averaged 0.03-0.13 diopter (D) higher than KIOLM (P > .05), KTNP averaged 1.16-1.21 D lower than KIOLM (P > .001), and KRP averaged 0.23-0.72 D lower than KIOLM (P > .001), with large variations in the measurements. The MedAE obtained with the different Pentacam K readings ranged from 0.44-0.64 D vs 0.52 D obtained with KIOLM (P > .05). MedAE was lower in all categories when the pupil was 3 mm or smaller.Conclusion: The Pentacam KF values were the closest to KIOLM and the KF readings from the 2-mm ring yielded the best results for IOL power calculation.