Interactive Threshold Research Articles

Comparison of Humphrey MATRIX and Swedish interactive threshold algorithm standard strategy in detecting early glaucomatous visual field loss

Purpose:The aim of this study was to compare the Humphrey MATRIX visual field (frequency doubling technology threshold) and Swedish interactive threshold algorithm (SITA) standard strategy white on white perimetry in detecting glaucomatous visual field loss.Material and Methods:Twenty-eight adult subjects, diagnosed to have glaucoma at a tertiary eye care hospital, who fulfilled the inclusion criteria, were included in this prospective study. All subjects underwent a complete ophthalmic examination. Subjects with glaucomatous optic disc changes underwent repeat perimetric examination on the same day with the Humphrey visual field analyzer (HFA II) and Humphrey MATRIX, the order of testing being random. Only reliable fields, where the HFA results corresponded to the disc changes were considered for analysis. A cumulative defect depth in each hemifield in both HFA and MATRIX reports was calculated.Results:Thirty-seven eyes of 24 subjects had reliable fields corresponding to optic disc changes. The mean age of the subjects was 56 ± 12 years. There were 12 males and 12 females. The test duration was significantly less on the MATRIX, mean difference in test duration was −81 ± 81.3 sec (p < 0.001). The mean deviation and the pattern standard deviation between the two instruments showed no significant difference (p = 0.55, p = 0.64 respectively) and a positive correlation coefficient of 0.63 and 0.72 respectively. Poor agreement was found with the glaucoma hemifield test.Conclusion:The Humphrey MATRIX takes less time in performing the test than SITA Standard and shows good correlation for mean deviation and pattern standard deviation. However, the glaucoma hemifield test showed poor agreement. The Humphrey MATRIX diagnoses were similar to established perimetric standards.

Relationship Between Visual Field Sensitivity and Retinal Nerve Fiber Layer Thickness Measured by Scanning Laser Polarimetry and Optical Coherence Tomography in Normal, Ocular Hypertensive and Glaucomatous Eyes

Purpose To evaluate the correlation between automated achromatic perimetry (AAP) and the output of two retinal nerve fiber layer (RNFL) analysers: scanning laser polarimetry (GDx-VCC) and optical coherence tomography (OCT). Methods Quantitative RNFL measurements with GDx-VCC and Stratus-OCT were obtained in one eye from 52 healthy subjects, 38 ocular hypertensive (OHT) patients and 94 glaucomatous patients. All patients underwent a complete examination, including AAP using the Swedish interactive threshold algorithm (SITA). The relationship between RNFL measurements and SITA visual field global indices were assessed by means of the following methods: analysis of variance, bivariate Pearson's correlation coefficient, multivariate linear regression techniques and nonlinear regression models, and the coefficient of determination (r 2) was calculated. Results RNFL thickness values were significantly lower in glaucomatous eyes than in healthy and ocular hypertensive eyes for both nerve fiber analysers ( P≤0.001), except for the inferior 120° average thickness in GDx-VCC. Linear regression models constructed for GDx-VCC measurements and OCT-derived RNFL thickness with SITA visual field global indices demonstrated that, for the mean deviation, the only predictor in the model was the nerve fiber indicator for GDx-VCC (r 2=0.255), and for the pattern standard deviation, the predictors in the model were the nerve fiber indicator for GDx-VCC (r 2=0.246) and the maximum thickness in the superior quadrant for Stratus-OCT (r 2=0.196). The best curvilinear fit was obtained with the cubic model. Conclusions Quantitative measurements of RNFL thickness using either GDx-VCC or OCT correlate moderately with visual field global indices in moderate glaucoma patients. We did not find a correlation between visual field global indices and RNFL thickness in early glaucoma patients. Further study is needed to develop new analytical methods that will increase RNFL analyser's sensitivity in early glaucoma patients.

Lack of DREAM Protein Enhances Learning and Memory and Slows Brain Aging

Memory deficits in aging affect millions of people and are often disturbing to those concerned. Dissection of the molecular control of learning and memory is paramount to understand and possibly enhance cognitive functions. Old-age memory loss also has been recently linked to altered Ca(2+) homeostasis. We have previously identified DREAM (downstream regulatory element antagonistic modulator), a member of the neuronal Ca(2+) sensor superfamily of EF-hand proteins, with specific roles in different cell compartments. In the nucleus, DREAM is a Ca(2+)-dependent transcriptional repressor, binding to specific DNA signatures, or interacting with nucleoproteins regulating their transcriptional properties. Also, we and others have shown that dream mutant (dream(-/-)) mice exhibit marked analgesia. Here we report that dream(-/-) mice exhibit markedly enhanced learning and synaptic plasticity related to improved cognition. Mechanistically, DREAM functions as a negative regulator of the key memory factor CREB in a Ca(2+)-dependent manner, and loss of DREAM facilitates CREB-dependent transcription during learning. Intriguingly, 18-month-old dream(-/-) mice display learning and memory capacities similar to young mice. Moreover, loss of DREAM protects from brain degeneration in aging. These data identify the Ca(2+)-regulated "pain gene" DREAM as a novel key regulator of memory and brain aging.

Comparing the Full-Threshold and Swedish Interactive Thresholding Algorithms for Short-Wavelength Automated Perimetry

To compare the Swedish interactive thresholding algorithm (SITA) with the full-threshold (FT) strategy for short-wavelength automated perimetry (SWAP). One eye of 286 patients with glaucomatous optic neuropathy (GON) and 289 age-matched participants without GON from the Diagnostic Innovations in Glaucoma Study (DIGS) and the African Descent and Glaucoma Evaluation Study (ADAGES) were classified with optic disc stereophotographs taken within 6 months of visual field testing, conducted within a 3-month period. Six parameters were derived per test, including pattern standard deviation (PSD) and the number of pattern deviation plot (PDP) points triggered at <1%. Receiver-operating characteristic (ROC) analysis equated the tests for specificity (80%, 90%, and 95%). Sensitivities of parameters with the highest area under the curve (AUC) and STATPAC (Carl Zeiss Meditec, Inc., Dublin, CA) PSD were compared. Agreement, severity, and test duration between algorithms were assessed. Sensitivities were not different between algorithms using PSD. With PDP <1%, SWAP-FT was more sensitive (35%) than SWAP-SITA (29%) at 95% specificity (P<0.05). Sensitivity and specificity using the STATPAC PSD at 95% (P<5%) and 99.5% (P<0.05%) was similar between algorithms. Severity correlated significantly between algorithms (P<0.001), although there was bias for SWAP-SITA to suggest more severe loss. SWAP-SITA required significantly less test time than did SWAP-FT (P<0.001). Mean differences in PSD, PDP <1%, and MD between algorithms were not clinically significant. Both algorithms performed similarly when equated for specificity. The reduced test duration makes SWAP-SITA the better choice. Testing with both algorithms within a short period is recommended for confirmation of results when switching from FT to SITA.

Comparison of the New Perimetric GATE Strategy with Conventional Full-Threshold and SITA Standard Strategies

A new, fast-threshold strategy, German Adaptive Thresholding Estimation (GATE/GATE-i), is compared to the full-threshold (FT) staircase and the Swedish Interactive Thresholding Algorithm (SITA) Standard strategies. GATE-i is performed in the initial examination and GATE refers to the results in subsequent examinations. Sixty subjects were recruited for participation in the study: 40 with manifest glaucoma, 10 with suspected glaucoma, and 10 with ocular hypertension. The subjects were evaluated by each threshold strategy on two separate sessions within 14 days in a randomized block design. SITA standard, GATE-i, and GATE thresholds were 1.2, 0.6, and 0.0 dB higher than FT. The SITA standard tended to have lower thresholds than those of FT, GATE-i, and GATE for the more positive thresholds, and also in the five seed locations. For FT, GATE-i, GATE, and SITA Standard, the standard deviations of thresholds between sessions were, respectively, 3.9, 4.5, 4.2, and 3.1 dB, test-retest reliabilities (Spearman's rank correlations) were 0.84, 0.76, 0.79, and 0.71, test-retest agreements as measured by the 95% reference interval of differences were -7.69 to 7.69, -8.76 to 9.00, -8.40 to 8.56, and -7.01 to 7.44 dB, and examination durations were 9.0, 5.7, 4.7, and 5.6 minutes. The test duration for SITA Standard increased with increasing glaucomatous loss. The GATE algorithm achieves thresholds that are similar to those of FT and SITA Standard, with comparable accuracy, test-retest reliability, but with a shorter test duration than FT.

Three Waves Interaction of Disterbanced in the Hypersonic Boundary Layer

In frames of the weakly nonlinear stability theory a disturbances interaction in a hypersonic boundary layer is considered. It is established that nonlinear interaction in a hypersonic boundary layer is probably, it is carried out between waves of the different nature (acoustical and vortical) in a parametric resonance regime. For three-dimensional vortical waves similar interaction is more intensively. The plane acoustical wave which increases more intensively in comparison with the threedimensional is the pumping wave. There are intensity threshold values of the nonlinear interaction beginning and threshold values of the explosive growth beginning. It is possible to expect, that nonlinear interactions for vortical waves which are carried out in wide frequency band can lead to a package growth of Tollmien-Schlichting waves.

Comparison Between Discriminant Analysis Models and “Glaucoma Probability Score” for the Detection of Glaucomatous Optic Nerve Head Changes

The aim of this study was to evaluate and compare 4 different discriminant analysis formulas and the new Glaucoma Probability Score (GPS) for the detection of morphometric optic nerve head changes in chronic open-angle glaucoma. This is a prospectively planned cross-sectional study. Two hundred and fourteen consecutive eyes were recruited into this study. For each patient, the eyes were evaluated by a slit lamp examination, and the visual fields were assessed by a Humphrey Field Analyzer 750 (HFA, Humphrey Inc, San Leandro, CA), using the standard full threshold 24-2 (Swedish Interactive Threshold Algorithm) program. The optic nerve heads were morphometrically evaluated using the Heidelberg Retina Tomograph 3 (HRT 3, Heidelberg Engineering, Heidelberg, Germany; software version 3.0). From the HRT data, 4 discriminant analysis formulas and the GPS were considered. All data were analyzed by Student t test and Pearson r coefficient. A linear regression model was also used to determine the independent contribution of variables included in the model. Sensitivity, specificity, diagnostic precision, and receiver operating characteristic curve areas were calculated for all the 5 methods examined. kappa statistic was used to study the agreement among, and between, the 5 different methods. One hundred and nineteen normal eyes and 95 eyes with primary open-angle glaucoma were included in the study. No significant difference was found between the 2 study subgroups in both age and refractive error. Significant (P<0.001) correlations were found between visual field indices and the HRT parameters. Sensitivity, specificity, and diagnostic precision of the 4 formulas ranged between 50% and 99.16%. Bathija et al's formula had the highest diagnostic precision, followed by Mikelberg's formula. Using kappa statistics, kappa ranged from 0.177 to 0.528 when comparing each single discriminant formula with the GPS. The GPS showed similar sensitivity and specificity to the Mikelberg and Bathija formulas; this method is a promising one for differentiating between healthy and glaucomatous eyes, requiring no subjective user input.

Comparison of the Humphrey Field Analyser and Humphrey Matrix Perimeter for the Evaluation of Glaucoma Patients

Aims: To compare the Humphrey Matrix Perimeter (HMP) with the Humphrey Field Analyser (HFA) in visual-field examinations of patients with glaucoma or suspected glaucoma. Methods: One hundred and forty-nine patients with suspected glaucoma or glaucoma were recruited. All patients underwent visual-field examinations with the Swedish Interactive Threshold Algorithm standard, the central 30-2 threshold test with the HFA, and the frequency doubling technique 30-2 threshold test with the HMP. The examination times, mean deviations (MDs) and pattern standard deviations (PSDs) of both perimeters were compared in all patients and according to the patient’s diagnosis or the severity of their visual-field defects (VFDs). The paired 2-tailed t test and Pearson’s correlation coefficients were used for statistical analyses. Results: Overall, the examination times were significantly shorter with the HMP than with the HFA. There was a positive correlation between the HFA and HMP measurements of MD and PSD. In patients with suspected glaucoma, the PSDs measured with the HMP were significantly higher than those measured with the HFA. In patients with mild VFDs (MD >–4.0 dB), PSDs measured with the HMP were significantly higher than those measured with the HFA. In patients with severe VFDs (MD <–12.0 dB), MDs measured with the HMP were significantly higher than those measured with the HFA, whereas PSDs measured with the HMP were significantly lower than those measured with the HFA. Conclusions: The HMP is more time efficient than the HFA in visual-field examinations. The HMP tends to overestimate mild VFDs and underestimate severe VFDs.

Visually assessed breast density, breast cancer risk and the importance of the craniocaudal view

IntroductionMammographic density is known to be a strong risk factor for breast cancer. A particularly strong association with risk has been observed when density is measured using interactive threshold software. This, however, is a labour-intensive process for large-scale studies.MethodsOur aim was to determine the performance of visually assessed percent breast density as an indicator of breast cancer risk. We compared the effect on risk of density as measured with the mediolateral oblique view only versus that estimated as the average density from the mediolateral oblique view and the craniocaudal view. Density was assessed using a visual analogue scale in 10,048 screening mammograms, including 311 breast cancer cases diagnosed at that screening episode or within the following 6 years.ResultsWhere only the mediolateral oblique view was available, there was a modest effect of breast density on risk with an odds ratio for the 76% to 100% density relative to 0% to 25% of 1.51 (95% confidence interval 0.71 to 3.18). When two views were available, there was a considerably stronger association, with the corresponding odds ratio being 6.77 (95% confidence interval 2.75 to 16.67).ConclusionThis indicates that a substantial amount of information on risk from percentage breast density is contained in the second view. It also suggests that visually assessed breast density has predictive potential for breast cancer risk comparable to that of density measured using the interactive threshold software when two views are available. This observation needs to be confirmed by studies applying the different measurement methods to the same individuals.

Increases in Serum Estrone Sulfate Level Are Associated with Increased Mammographic Density during Menopausal Hormone Therapy

Menopausal hormone therapy increases mammographic density. We determined whether increases in serum estrone sulfate (E(1)S) levels during menopausal hormone therapy predict increased mammographic density. We measured percent mammographic density and serum E(1)S levels in 428 participants of the Postmenopausal Estrogen/Progestin Interventions study who were randomly assigned to daily conjugated equine estrogen (CEE) 0.625 mg alone, CEE + daily medroxyprogesterone acetate (MPA) 2.5 mg, CEE + cyclical MPA (10 mg days 1-12 per 28-day cycle), or CEE + cyclical micronized progesterone (10 mg days 1-12). Serum E(1)S levels were determined by RIA. Information about covariates was determined by annual questionnaire. Using linear regression, we determined the association between change in E(1)S level from baseline to 12 months and change in percent mammographic density (by semiquantitative interactive threshold method). After controlling for baseline mammographic density, age, body mass index, alcohol intake, parity, smoking, ethnicity, physical activity, and age at first pregnancy, mammographic density increased by 1.3% for every 1 ng/mL increase in E(1)S level (P < 0.0001). The association between change in E(1)S level and change in mammographic density differed by treatment group (greater effect in CEE + cyclical MPA group versus CEE group; P = 0.05). After controlling for treatment group, change in the ratio of E(1)S to E(1) was also positively associated with change in mammographic density. Increases in serum E(1)S levels during menopausal hormone therapy are associated with increases in mammographic density. The relative contribution of E(1)S and E(1) to stimulation of breast tissue awaits further elucidation.

Comparison of Different Analytic Algorithms for Interpretation of the Swedish Interactive Threshold Algorithm Strategy

OBJECTIVETo compare 4 analytic algorithms for interpretation of the Swedish Interactive Threshold Algorithm.INTRODUCTIONAnalytic algorithms were initially developed for interpretation of standard automated perimetry (using a full threshold strategy). The Swedish interactive threshold algorithm is a novel strategy that was developed to shorten test duration.METHODSOne hundred forty-three printouts of normal and glaucomatous patients were analyzed using Caprioli’s (strict, moderate and liberal) criteria and Anderson’s modified criteria for perimetric defect. Areas under the receiver operator characteristics (ROC) curves, sensitivity, and specificity for each criteria were calculated.RESULTSCaprioli’s strict and Anderson’s modified criteria presented similar sensitivity (94.5% and 92.3%, respectively) and specificity (63.5% and 61.5%, respectively). Caprioli’s liberal criteria were more sensitive (98.9%) and less specific (42.5%) than the other three criteria.CONCLUSIONBoth Caprioli’s and Anderson’s modified criteria can be used for interpretation of the Swedish interactive threshold algorithm.

Poster 49: Bitemporal Hemianopia Arising From a Suprasellar Craniopharyngioma

Purpose: The Swedish Interactive Thresholding Algorithm (SITA) is a new testing strategy for the Humphrey perimeter. The standard SITA algorithm shortens test time in adults without increasing variability, but its usefulness for detecting field defects in children has not been investigated. Methods: We evaluated 92 standard SITA 24-2 visual fields of children, most of whom had various types of optic neuropathies (pediatric idiopathic intracranial hypertension, homonymous defects, bitemporal defects, papilledema from brain tumors), and compared them with 49 full threshold 24-2 fields obtained in similar patients. We evaluated outcome measures of foveal threshold, mean defect, pattern standard deviation, false-negative and false-positive rates, and test time. Five children (9 eyes) had both SITA and full threshold testing (FTT). Results: The SITA decreased test time by over 50% compared with FTT (12.6 ± 3.0 minutes vs 6.6 ± 1.6 minutes [P < .00001]). When patients with field defects were eliminated, the pattern standard deviation was lower with SITA than FTT (P < .002), indicating lower intratest variability of SITA in subjects with normal fields. No detectable difference was observed in the other outcome measures. Subjective analysis of gray-scale fields in patients who underwent testing with the use of both strategies showed marked similarities. Conclusions: SITA shortens test time significantly compared with FTT and does so without jeopardizing interpretability. SITA has less intratest variability than FTT and therefore should be better for detecting and following defects. Caution is advised when following a visual field defect unless the same strategy is used for each evaluation. Switching strategies in the absence of a stable field defect is not recommended. (J AAPOS 2001;5:114-7)

Retrobulbar hemodynamic parameters in pseudoexfoliation syndrome and pseudoexfoliative glaucoma

To compare the hemodynamic parameters in the retrobulbar vessels in pseudoexfoliative syndrome (PXS), pseudoexfoliative glaucoma (PXG), and age-matched healthy subjects by using color Doppler imaging (CDI). 72 eyes from 72 patients with PXS, 70 eyes from 70 patients with PXG, and 66 eyes from 66 age-matched healthy subjects who met the inclusion/exclusion criteria were included in this prospective cross-sectional study. Peak systolic velocity (PSV), end-diastolic velocity (EDV), and Pourcelot resistance index (RI) were assessed in the ophthalmic artery (OA), central retinal artery (CRA), and temporal short-posterior ciliary arteries (SPCA). Visual function was assessed using the 24-2 Swedish Interactive Threshold Algorithm (SITA). The main outcomes of the study were PSV, EDV and RI in the OA, SPCA, and CRA. The EDV in the OA, SPCA and the CRA was decreased significantly (p < 0.001, <0.001, and 0.003 respectively) in the eyes of PXG patients compared with controls and PSX respectively. The RI in the OA, SPCA, and the CRA was significantly higher (p = 0.022, 0.005, and 0.007 respectively) in the eyes of PXG patients compared with healthy controls and PSX patients respectively. The mean difference in mean EDV in the OA between the control group and the PXS was 0.18 cm/s, 95% confidence interval (CI) -0.60 to 0.95, p = 0.661. The mean difference in mean EDV in the SPCA between the control healthy subjects and the pseudoexfoliative subjects was -0.18 cm/s, 95% CI -0.45 to 0.08, p = 0.176. Multivariate regression analysis showed that in the PXG patients the PSV and EDV in the CRA were significantly positively correlated with the mean defect (p = 0.006 and 0.002 respectively). The RI in the CRA was significantly negatively correlated with the mean defect in PXG patients, p = 0.009. The results of this study showed that the retrobulbar hemodynamics might be disturbed in patients with PXG, especially in the central retinal artery. Our results have found no significant differences in the retrobulbar hemodynamic parameters between pseudoexfoliative syndrome patients and age-matched healthy subjects.

Evaluating the Effectiveness of Using Standard Mammogram Form to Predict Breast Cancer Risk: Case-Control Study

Breast density is a well-known breast cancer risk factor. Most current methods of measuring breast density are area based and subjective. Standard mammogram form (SMF) is a computer program using a volumetric approach to estimate the percent density in the breast. The aim of this study is to evaluate the current implementation of SMF as a predictor of breast cancer risk by comparing it with other widely used density measurement methods. The case-control study comprised 634 cancers with 1,880 age-matched controls combined from the Cambridge and Norwich Breast Screening Programs. Data collection involved assessing the films based both on Wolfe's parenchymal patterns and on visual estimation of percent density and then digitizing the films for computer analysis (interactive threshold technique and SMF). Logistic regression was used to produce odds ratios associated with increasing categories of breast density. Density measures from all four methods were strongly associated with breast cancer risk in the overall population. The stepwise rises in risk associated with increasing density as measured by the threshold method were 1.37 [95% confidence interval (95% CI), 1.03-1.82], 1.80 (95% CI, 1.36-2.37), and 2.45 (95% CI, 1.86-3.23). For each increasing quartile of SMF density measures, the risks were 1.11 (95% CI, 0.85-1.46), 1.31 (95% CI, 1.00-1.71), and 1.92 (95% CI, 1.47-2.51). After the model was adjusted for SMF results, the threshold readings maintained the same strong stepwise increase in density-risk relationship. On the contrary, once the model was adjusted for threshold readings, SMF outcome was no longer related to cancer risk. The available implementation of SMF is not a better cancer risk predictor compared with the thresholding method.

Total Deviation Probability Plots for Stimulus Size V Perimetry

To compare empirical probability plots in patients with glaucoma for size V and III perimetry testing. We computed empirical probability plot percentile limits after testing 60 age-matched controls tested with both size III (Swedish interactive thresholding algorithm) and size V (full threshold) perimetry twice. Probability plots of 120 patients with glaucoma tested in the same way were computed. We compared the number of abnormal test locations in the 2 stimulus sizes; we then compared these results with those from size III StatPac software (Zeiss Humphrey Systems, Dublin, California) using 2-way repeated-measures analysis of variance. We found a similar number of abnormal test locations (P < or = .05) for the size III and size V testing conditions identified by the probability plots (no significant difference); there were significantly fewer abnormal locations using StatPac (size III) than from our size III database. When results were stratified by mean deviation, the mild visual loss group again did not show any significant differences between sizes III and V. Size V full-threshold testing gives a similar number of abnormal test locations in patients with glaucoma compared with the size III Swedish interactive thresholding algorithm standard test. Size V testing, with its greater dynamic range and lower variability, may be a viable alternative to size III testing in patients with glaucoma.

Eye on the Bayou: New Concepts in Glaucoma, Cataract and Neuro-Ophthalmology

Jonathan D. Nussdorf, MD. Kugler Publishers, The Hague, Netherlands, 2006. ISBN: 978-90-6299-209-6, $108.00. Scope: This book is a collection of the lectures and roundtable discussions from the 54th Annual Symposium of the New Orleans Academy of Ophthalmology. The book is divided into four main sections: neuro-ophthalmology, glaucoma, psychophysics, and anterior segment surgery. The target reader is the comprehensive ophthalmologist. Each subspecialty section contains the text of several lectures and roundtable discussions designed to address questions introduced by the preceding lectures. The roundtable panel consists of several “experts” who discuss their philosophy on difficult management issues. The neuro-ophthalmology section contains transcripts of Andrew Lee's excellent lectures on common mistakes when examining the neuro-ophthalmology patient, double vision and pupil involvement, an update on optic neuritis, and important points to communicate to patients with nonarteritic anterior ischemic optic neuropathy. Additionally, Lee discusses MRI, CT, and optical coherence tomography (OCT) indications in neuro-ophthalmology. The second section includes lectures by Harry Quigley and Eve Higginbotham that cover epidemiological risk factors for glaucoma such as race and sex. This is followed by a discussion on low tension glaucoma and neuroprotection. Paul Palmberg critiques the commonly held belief that glaucoma structural damage precedes visual function loss. Finally, there are several succinct synopses of recent landmark glaucoma clinical trials (CNTGS, AGIS, EMGT, CIGTS, OHTS, and EGPS) followed by an interesting roundtable discussion critiquing these clinical trials. The psychophysics section is primarily a series of lectures updating visual field testing with short wavelength automated perimetry (SWAP), frequency doubling technology (FDT), Swedish interactive thresholding algorithm (SITA), zippy estimation of sequential testing (ZEST), and tendency oriented perimetry (TOP). Additionally, there is a section on interpreting visual field loss in glaucoma and a roundtable discussion on detecting and monitoring glaucoma progression. The final section consists of several lectures on anterior segment surgery and complications. The first lecture discusses the new disease entity “toxic anterior segment syndrome.” The remaining lectures are discussions of the basics of laser trabeculoplasty and clinical pearls on performing and managing trabeculectomy. Two roundtable discussions cover trabeculectomy skills by providing further pearls and suggestions for surgical infection prophylaxis. Strengths: This book contains many useful diagnostic pearls relevant to comprehensive ophthalmologists. The text is easy to follow. The neuro-ophthalmology section is especially well done and practical. The roundtable discussions are insightful. Weaknesses: The topics covered are relatively narrow. There is no index. If readers are not looking for updates on the specific topics, they may find the book focused on too little. Recommended Audience: This book is aimed to the comprehensive ophthalmologist or specialist interested in updating knowledge in a different subspecialty. Additionally, individuals who attended the 54th Annual Symposium of the New Orleans Academy of Ophthalmology can use this book to review the material. Critical Appraisal: This book provides a practical, succinct update on narrow but important topics to the practicing comprehensive ophthalmologist or resident physician. Christopher Thiagarajah, MD Karl Golnik, MD, MEd University of Cincinnati and the Cincinnati Eye Institute Cincinnati, Ohio

Evaluation of Threshold Estimation and Learning Effect of two Perimetric Strategies, Sita Fast and Clip, in Damaged Visual Fields

The threshold estimation, learning effect, and between-algorithm differences of the Fast Swedish Interactive Thresholding Algorithm (SITA Fast), of the Humphrey Field Analyzer (HFA), and the Continuous Light Increment Perimetry (CLIP) strategy of the Oculus Twinfield perimeter were evaluated in damaged visual fields. Twenty-one glaucomatous patients with damaged visual fields (MD worse than -8 dB) underwent Oculus Full Threshold (FT), Humphrey FT, SITA Fast, and CLIP 30-2 perimetric examinations. All the tests were repeated in a second session at least 3 days later. The point-wise differences in absolute sensitivity and of the total deviation plot values between FT and fast algorithms, between fast algorithms and the learning effect were evaluated (Wilcoxon test and Bland-Altman analysis). The average point-wise sensitivity difference between SITA Fast and HFA FT strategy (0.84 dB) was significantly lower than that found between CLIP and Oculus FT strategy (1.71 dB). Between-algorithm point-wise differences of the total deviation plot values of the fast strategies were not significantly different. Learning effect for SITA Fast (0.67 dB) was higher than that found for CLIP (0.39 dB). Test time for SITA (367+/-71 sec) and CLIP (453+/-98 sec) were about 55% and 35%, respectively, shorter (p<0.001) than those found with FT algorithms. The acceptance for fast algorithms and particularly for CLIP was significantly better. The two fast strategies, even though using very different algorithms, showed good threshold estimation compared to FT strategies with a consistent time saving in damaged visual fields.

Humphrey Matrix Perimetry in Optic Nerve and Chiasmal Disorders: Comparison with Humphrey SITA Standard 24-2

To compare the Humphrey Matrix 24-2 perimetry (Matrix; Carl Zeiss Meditec, Inc., Dublin, CA) with the standard automated perimetry Humphrey Visual Field Analyzer using SITA (Swedish Interactive Threshold Algorithm) program 24-2 (SAP; Carl Zeiss Meditec, Inc.) in neuro-ophthalmic disorders affecting the optic nerve and chiasm. Matrix and SAP were performed on 93 patients with neuro-ophthalmic disorders affecting the optic nerve and optic chiasm. Three readers compared the total and pattern deviation probability plots and judged the similarity and the extent of the visual field defects. The sensitivity and specificity of both perimeters were calculated. Concordance was good in 61%, fair in 30%, and poor in 9% of the total deviation plots. For the pattern deviation, concordance was good in 52%, fair in 34%, and poor in 14%. The extent of field loss was equal in 50%, 23% more extensive with Matrix, and 27% more extensive with SAP for total deviation plots. For the pattern deviation, the extent was equal in 47%, 20% more extensive with Matrix and 33% more extensive with SAP. The sensitivity for detecting defects was 84% (SAP) and 77% (Matrix) for total deviation and 80% (SAP) and 79% (Matrix) for pattern deviation (no significant difference, P > 0.05). The specificity was 84% (SAP) and 86% (Matrix) for total deviation and 68% (SAP) and 74% (Matrix) for pattern deviation (no significant difference, P > 0.05). The new Humphrey Matrix 24-2 testing strategy provides a visual field testing method for optic nerve and chiasmal disorders that has fair to good concordance with the Humphrey SITA Standard 24-2 program. Both tests have similar sensitivity and specificity.

Parallel assessment of the impact of different hormone replacement therapies on breast density by radiologist- and computer-based analyses of mammograms

Objectives First, to compare the impact of nasally and orally dosed estradiol on breast density; second, to investigate the utility of computer-based automated approaches to the assessment of breast density with reference to traditional methods.Methods Digitized images from two 2-year, randomized, placebo-controlled trials formed the basis of the present post hoc analysis. Active treatments were 1 mg estradiol continuously combined with 0.125 mg trimegestone (oral hormone replacement therapy, HRT) or low-dose (150 or 300 µg estradiol) nasal estradiol cyclically combined with 200 mg micronized progesterone (nasal HRT). The effects on breast density were assessed by a radiologist, providing the BI-RADS® score and the interactive threshold, and by a computer-based approach, providing the measure of stripiness and the HRT-effect specific measure of breast density.Results In the oral HRT trial, active treatment induced a significant increase in breast density, which was consistent in all methods used (all p < 0.05). In contrast, none of the methods detected significant changes in women receiving nasal HRT. The sensitivity of automated methods to discriminate HRT- from placebo-treated women was equal or better than the sensitivity of methods performed by the radiologist.Conclusions The markedly different pharmacokinetic profile of nasal estrogen seems to be associated with better breast safety. Automated computer-based analysis of digitized mammograms provides a sensitive measure of changes in breast density induced by hormones and could serve as a useful tool in future clinical trials.

Multimodal virtual bronchoscopy using PET/CT images

Objective: To demonstrate the possibilities, advantages and limitations of virtual bronchoscopy using data sets from positron emission tomography (PET) and computed tomography (CT).Materials and Methods: Eight consecutive patients with non-small cell lung cancer (NSCLC) underwent PET/CT. PET was performed with a glucose analog, 2-[fluorine-18]-fluoro-2-deoxy-D-glucose (18F-FDG), using a state-of-the-art full-ring Pico-3D PET scanner. CT was performed with a venous-dominant contrast-enhanced phase using a 16-slice CT scanner. The tracheobronchial system was segmented using the CT data set with an interactive threshold interval volume-growing segmentation algorithm. The primary tumors and lymph node metastases were segmented for virtual CT-bronchoscopy using the CT data set and for virtual hybrid bronchoscopy using the PET/CT data set. The structures of interest were visualized with a color-coded shaded-surface rendering method.Results: The use of CT and virtual CT-bronchoscopy primarily facilitates visualization of the anatomical details of the tracheobronchial system and detection of anatomical/morphologic structural changes caused by disease. PET/CT and virtual hybrid bronchoscopy, or virtual PET/CT-bronchoscopy, give superior results to virtual CT-bronchoscopy because the hybrid bronchoscopy uses both the CT information and the molecular/metabolic information about the disease obtained from PET.Conclusions: PET/CT imaging has proven to be a highly valuable oncological diagnostic modality. Virtual hybrid bronchoscopy can be performed using a low-dose CT scan or diagnostic CT. However, it is expected to improve diagnostic accuracy in identification and characterization of malignancies, verification of infections, and differentiation of viable tumor tissue from atelectases and scar tissue, as well as assessment of tumor staging and therapeutic response, and detection of early stage recurrences that are not detectable or are liable to be misjudged using virtual CT-bronchoscopy. It could also be useful as a screening examination method for patients with suspected endobronchial malignancy. Virtual hybrid bronchoscopy with a transparent color-coded shaded-surface rendering model offers a useful alternative to fiberoptic bronchoscopy, and is particularly promising for patients for whom fiberoptic bronchoscopy is not feasible, contraindicated or refused.