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Savini G.,GB Bietti Eye Foundation IRCCS | Barboni P.,Studio Oculistico dAzeglio | Barboni P.,University of Bologna | Parisi V.,GB Bietti Eye Foundation IRCCS | Carbonelli M.,GB Bietti Eye Foundation IRCCS
British Journal of Ophthalmology | Year: 2012

Background: To evaluate the influence of axial length on measurements of the retinal nerve fibre layer (RNFL) thickness and optic nerve head (ONH) parameters in healthy subjects. Methods: Using Cirrus HD-OCT, RNFL thickness and ONH parameters (disc and rim area) were measured in 15 short (<22.5 mm), 15 medium (22.51-25.5 mm) and 15 long (>25.51 mm) eyes. Results: The mean axial length was 21.5±0.5 mm in short eyes, 24.1±0.8 mm in medium eyes and 26.6±1.0 mm in long eyes. The RNFL thickness decreased with longer axial lengths in the superior (r=-0.52, r 2=0.27, p=0.0003), inferior (r=-0.72, r 2=0.52, p<0.0001), nasal (r=-0.60, r 2=0.37, p<0.0001) and temporal (r=-0.30, r 2=0.09, p=0.0485) quadrants, as well as in the 360° mean measurement (r=-0.69, r 2=0.48, p<0.0001). The optic-disc area (r=-0.74, r 2=0.54, p<0.0001) and rim area (r=-0.41, r 2=0.17, p=0.0051) decreased with longer axial lengths. Correcting for axial length-induced ocular magnification by means of the Littmann formula resolved the relationship between axial length and both RNFL thickness and ONH area. Discussion: Axial length influences measurements of RNFL thickness and ONH parameters in healthy subjects. Caution is recommended when comparing the measured values of myopic and hyperopic eyes with the normative database of the instrument.


Savini G.,Gb Bietti Eye Foundation Irccs | Barboni P.,Studio Oculistico dAzeglio | Carbonelli M.,Gb Bietti Eye Foundation Irccs | Hoffer K.J.,University of California at Los Angeles | Hoffer K.J.,St Marys Eye Center
Journal of Cataract and Refractive Surgery | Year: 2012

Purpose: To assess the accuracy of the corneal power measurements with a new Scheimpflug camera combined with Placido-disk corneal topography (Sirius) (combined Scheimpflug camera-topographer) for intraocular lens (IOL) power calculation in unoperated eyes and compare the results with those by a validated corneal topographer (Keratron) (validated topographer). Setting: Private practice. Design: Case series. Methods: Consecutive patients having phacoemulsification and in-the-bag IOL implantation were studied. Intraocular lens power was calculated using the Hoffer Q, Holladay 1, and SRK/T formulas; the axial length, as measured by ultrasound immersion biometry; and 3 corneal power measurements: validated topographer simulated keratometry (K); combined Scheimpflug camera-topographer simulated K (derived from anterior corneal curvature only); combined Scheimpflug camera-topographer mean pupil power (derived from anterior and posterior corneal curvatures through ray tracing). The prediction error was calculated as the difference between the predicted refraction and the refraction measured 1 month postoperatively. Results: When the corneal power measurements from the combined Scheimpflug camera-topographer were used, the mean absolute error (MAE) ranged between 0.23 diopter (D) ± 0.24 (SD) (simulated K and Hoffer Q formula) and 0.33 ± 0.23 D (mean pupil power and SRK/T formula). There were no statistically significant differences between the MAE generated by the simulated Ks of the 2 devices with any of the 3 formulas. Conclusion: Both corneal power measurements (simulated K and mean pupil power) provided by the new combined Scheimpflug camera-topographer were successfully entered into third-generation IOL power calculation formulas in unoperated eyes. Financial Disclosure: Dr. Hoffer is the author of the Hoffer Q formula and owns the EyeLab, which sells Hoffer Programs. No other author has a financial or proprietary interest in any material or method mentioned. © 2012 ASCRS and ESCRS.


Savini G.,Gb Bietti Eye Foundation Irccs | Hoffer K.J.,University of California at Los Angeles | Hoffer K.J.,St Marys Eye Center | Carbonelli M.,Gb Bietti Eye Foundation Irccs
Journal of Refractive Surgery | Year: 2013

PURPOSE: To compare anterior chamber depth (ACD) and aqueous depth (AQD) measurements provided by a Scheimpflug camera combined with corneal topography to those obtained by immersion ultrasound (US) biometry when assessing the distance between the cornea and intraocular lens (IOL) in pseudophakic patients. METHODS: In a sample of 40 consecutive patients, each patient underwent measurements of ACD and AQD by means of the two techniques. Scheimpflug (Sirius; C.S.O., Firenze, Italy) measurements were obtained by manually tracing a line between the anterior surface of the IOL and the central cornea. Results were compared by t test. Agreement was evaluated by Bland-Altman plots with 95% limits of agreement (LoA). RESULTS: There was no statistically significant difference between the AQD as measured by US (3.95 ± 0.34 mm; range: 3.39 to 4.74 mm) and the AQD as measured by Scheimpflug photography (3.96 ± 0.34 mm; range: 3.41 to 4.77 mm; P = .3187). The statistically (but not clinically) significant difference between the ACD as measured by US (4.54 ± 0.37 mm; range: 3.93 to 5.35 mm) and Scheimpflug photography (4.58 ± 0.34 mm; range: 4.03 to 5.36 mm; P = .0024) disappeared after setting the US speed for ACD at 1,545 m/sec (mean ACD: 4.58 ± 0.37 mm; range: 3.96 to 5.39 mm). The 95% LoA ranged between -0.15 and +0.18 mm for AQD and between -0.12 and +0.21 mm for ACD. CONCLUSIONS: In pseudophakic eyes, the manual ACD and AQD measurements obtained from the Scheimpflug camera combined with corneal topography are not significantly different compared to those provided by US and therefore can be considered interchangeable with the latter. Copyright © SLACK Incorporated.


Coppola G.,Gb Bietti Eye Foundation Irccs | Schoenen J.,University of Liège
Current Pain and Headache Reports | Year: 2012

A proportion of episodic migraine patients experiences a progressive increase in attack frequency leading to chronic migraine (CM). The most frequent external factor that leads to headache chronification is medication overuse. The neurobiological bases of headache chronification and of the vicious circle of medication overconsumption are not completely elucidated. More recently, the same neurophysiological methods used to study episodic migraine were applied to CM and medication-overuse headache (MOH). Studies of cortical responsivity tend overall to indicate an increase in excitability, in particular of somatosensory and visual cortices, reflected by increased amplitude of evoked responses, decreased activity of inhibitory cortical interneurons reflected in the smaller magnetic suppression of perceptual accuracy, and, at least for visual responses, an increase in habituation. In MOH, overconsumption of triptans or NSAIDs influences cortical excitability differently. Generalized central sensitization is suggested to play an important role in the pathophysiology of headache chronification. © 2011 Springer Science+Business Media, LLC.


Coppola G.,Gb Bietti Eye Foundation Irccs | Schoenen J.,University of Liège
Current Opinion in Supportive and Palliative Care | Year: 2012

Purpose of review: We highlight the recent clinical trials for the management of acute and chronic migraine. Recent findings: In women with menstrual migraine, triptans seem to be well tolerated irrespective of whether or not patients are taking oestrogen-containing contraceptives or have comorbidities that indicate increased cardiovascular risk. The new acute drug, telcagepant, a calcitonin gene-related peptide (CGRP) antagonist, is safe for long-term use (up to 18 months) in migraine patients with stable coronary artery disease in whom the use of triptans is not advisable. From the pooled analysis of the two Phase III Research Evaluating Migraine Prophylaxis Therapy studies of onabotulinumtoxin A (BOTOX) in chronic migraineurs, it clearly emerged that efficacy increases overtime (up to 56 weeks) and paralleled self-perceived improvement in quality of life. Effectiveness was also observed in patients with severely disabling headaches, who met criteria for triptan abuse and were refractory to several prophylactic treatments. Finally, combination of preventive pharmacological agents with different action mechanisms may be the next frontier in therapeutic advancements for treating migraine. Summary: Although triptans are safe and well tolerated, CGRP antagonists may be an option for nonresponsive patients or those in whom the use of triptans is not advisable. New drugs and combinations of old therapeutic options may help patients with severe forms of headache. © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins.


Savini G.,Gb Bietti Eye Foundation Irccs | Barboni P.,Studio Oculistico dAzeglio | Carbonelli M.,Gb Bietti Eye Foundation Irccs | Hoffer K.J.,University of California at Los Angeles
Journal of Cataract and Refractive Surgery | Year: 2011

Purpose: To assess the repeatability of anterior segment measurements performed by a Scheimpflug camera combined with Placido corneal topography (Sirius) in unoperated, post-refractive surgery, and keratoconus eyes. Setting: Private clinical ophthalmology practice. Design: Evaluation of diagnostic test or technology. Methods: Three consecutive scans were acquired for each eye. The following parameters were evaluated: simulated keratometry, posterior corneal power, mean pupil power (ie, corneal power assessed by ray tracing through the anterior and posterior corneal surfaces), corneal asphericity, thinnest and apex corneal thickness, aqueous depth, anterior chamber volume, and corneal spherical aberration. Repeatability was assessed using test-retest variability, the coefficient of variation, and the intraclass correlation coefficient (ICC). Results: Sixty-four unoperated eyes, 17 eyes that had myopic excimer laser surgery, and 13 eyes with keratoconus were analyzed. High repeatability was achieved for most parameters in the 3 groups, with an ICC higher than 0.99 for all measurements except posterior corneal power and mean pupil power in keratoconus (ICC, 0.868 and 0.976, respectively), anterior and posterior asphericity in normal eyes (ICC, 0.904 and 0.977, respectively), and spherical aberration in normal eyes (ICC, 0.806), post-refractive surgery eyes (ICC, 0.980), and keratoconus eyes (ICC, 0.981). Conclusion: The anterior segment measurements provided by the new Scheimpflug camera-Placido corneal topography system were highly repeatable and can be relied on in clinical routine and for research purposes. Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned. © 2011 ASCRS and ESCRS.


Savini G.,Gb Bietti Eye Foundation Irccs | Hoffer K.J.,University of California at Los Angeles | Ducoli P.,Gb Bietti Eye Foundation Irccs
Journal of Refractive Surgery | Year: 2013

PURPOSE: The AcrySof Toric intraocular lens (IOL) (Alcon Laboratories, Inc., Fort Worth, TX) is designed to correct corneal astigmatism ranging from 0.67 to 4.11 diopters (D). The authors reviewed the clinical outcomes of this IOL and investigated possible improvements of the online calculator provided by the manufacturer. METHODS: Review of published studies. RESULTS: The AcrySof Toric IOL can provide good results, although a mean overcorrection or undercorrection relative to the intended correction has been found by some authors. Stability over time has been reported to be excellent. Rotation occurs mainly in the fi rst postoperative month and is greater in eyes with a longer axial length due to the larger capsule size. The online calculator of this IOL may be improved by considering the posterior corneal astigmatism and better calculating the conversion of the IOL cylinder from the IOL plane to the corneal plane, which may be inaccurate for two reasons. First, given the variable distance between the IOL and the cornea in short and long eyes, the fi xed ratio (1.46) provided by the manufacturer cannot be used to calculate this conversion. Second, the online calculator does not take into account the effect of varying IOL sphere power. CONCLUSION: The AcrySof Toric IOL is a reliable choice to correct corneal astigmatism at the time of cataract surgery. Results will be improved once the online calculator by the manufacturer considers the posterior corneal astigmatism and the variable ratio between the toricity at the IOL and corneal plane. Copyright © SLACK Incorporated.


Savini G.,Gb Bietti Eye Foundation Irccs | Carbonelli M.,Studio Oculistico dAzeglio | Barboni P.,Studio Oculistico dAzeglio | Hoffer K.J.,University of California at Los Angeles
Journal of Cataract and Refractive Surgery | Year: 2011

Purpose: To assess the repeatability of the anterior segment measurements performed with a dual Scheimpflug analyzer (Galilei) in unoperated and post-refractive surgery eyes. Setting: Private practice. Design: Evaluation of diagnostic test. Methods: Three consecutive scans were acquired in unoperated eyes and in eyes that had excimer laser surgery for myopia. Unoperated eyes were enrolled from 3 subgroups: younger than 50 years, aged between 50 and 70 years, and older than 70 years. The following parameters were evaluated: simulated keratometry, posterior corneal power, total corneal power, anterior and posterior best-fit sphere radius, mean and thinnest central corneal thickness, anterior chamber depth and volume, horizontal and vertical corneal diameter, iridocorneal angle in the 4 quadrants, and corneal spherical aberration. Repeatability was assessed using analysis of variance (ANOVA), the coefficient of variation (COV), intraclass correlation (ICC), and test-retest variability. Results: The study evaluated 45 unoperated eyes (n = 45) and 15 post-refractive surgery eyes (n = 15). Each age subgroup in the unoperated group comprised 15 eyes. The ANOVA did not detect significant differences between the 3 measurements for any parameter. The COV was less than 0.5% for corneal power measurements and less than 3.5% for all remaining parameters except spherical aberration (16.68%). The ICC was more than 0.99 for corneal power measurements and more than 0.94 for all remaining parameters. Conclusions: The anterior segment measurements provided by the dual Scheimpflug analyzer were highly repeatable. Repeatability did not change with age or after myopic photorefractive keratectomy or laser in situ keratomileusis. Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned. © 2011 ASCRS and ESCRS.


Savini G.,Gb Bietti Eye Foundation Irccs | Carbonelli M.,Studio Oculistico dAzeglio | Barboni P.,Studio Oculistico dAzeglio
Current Opinion in Ophthalmology | Year: 2011

PURPOSE OF REVIEW: As spectral-domain optical coherence tomography (SD-OCT) progressively replaces time-domain OCT (TD-OCT) in the clinical and research setting, several commercially available instruments and new software upgrades for glaucoma diagnosis and progression analysis have been developed. Over the last year, several studies have been performed to assess the diagnostic performance of most of these instruments necessitating a review of their findings. RECENT FINDINGS: When compared with the measurements provided by TD-OCT, the conventional peripapillary circular scans by SD-OCT, which aim to measure the retinal nerve fiber layer (RNFL) thickness, show higher repeatability and similar diagnostic sensitivity. New software capabilities, such as the RNFL deviation map of Cirrus HD-OCT (Carl Zeiss Meditec, Dublin, CA) or the macular Ganglion Cell Complex scan of RTVue (Optovue, Fremont, CA), provide complementary information that enhances our ability to discriminate between healthy and glaucomatous eyes. SUMMARY: SD-OCT-based instruments represent a technological advancement in the diagnosis of glaucoma. Improved repeatability will facilitate more reliable follow-up and progression analysis. © 2011 Lippincott Williams & Wilkins, Inc.


Savini G.,Gb Bietti Eye Foundation Irccs | Hoffer K.J.,University of California at Los Angeles | Carbonelli M.,Studio Oculistico dAzeglio | Barboni P.,Studio Oculistico dAzeglio
Journal of Cataract and Refractive Surgery | Year: 2010

Purpose: To compare results of intraocular lens (IOL) power calculation methods after myopic excimer laser surgery. Setting: Private practice. Methods: In this prospective study, eyes having phacoemulsification after myopic excimer laser surgery were classified into Group 1 (preoperative corneal power available, refractive change known), Group 2 (preoperative corneal power available, refractive change uncertain), and Group 3 (preoperative corneal power unavailable, refractive change known even if uncertain). The IOL power was calculated using the following methods: clinical history, Awwad, Camellin/Calossi, Diehl, Feiz, Ferrara, Latkany, Masket, Rosa, Savini, Shammas, Seitz/Speicher, and Seitz/Speicher/Savini. Results: The lowest mean absolute errors (MAEs) in IOL power prediction in Group 1 (n = 12) and Group 2 (n = 11), respectively, were with the methods of Seitz/Speicher/Savini (0.51 diopter [D] ± 0.44 [SD] and 0.55 ± 0.50 D), Seitz/Speicher (0.58 ± 0.47 D and 0.54 ± 0.45 D), Savini (0.60 ± 0.44 D and 0.65 ± 0.63 D), Masket (0.82 ± 0.49 D and 0.69 ± 0.51 D), and Shammas (0.77 ± 0.43 D and 1.11 ± 0.50 D). In Group 3 (n = 5), the lowest MAEs were with the methods of Masket (0.23 ± 0.27 D), Savini (0.49 ± 0.86 D), Seitz/Speicher/Savini (0.68 ± 0.36 D), Shammas (0.84 ± 0.98 D), and Camellin/Calossi (0.91 ± 0.84 D). Conclusions: When corneal power is known, the Seitz/Speicher method (with or without Savini adjustment) seems the best solution to obtain an accurate IOL power prediction. Otherwise, the Masket method may be the most reliable option. Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned. © 2010 ASCRS and ESCRS.

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