This paper puts forward a multi-loop nonlinear control (MLNC) strategy to overcome the limited performance of LTI controllers due to the so-called "waterbed" effect. According to "Bode's sensitivity integral", increasing the bandwidth or additional integral gain of LTI controller to improve the low-frequency disturbance attenuation irrefutably increases the sensitivity to high-frequency disturbances or measurement noise. Hence, it is impossible to attain the best of both worlds in the case of linear controllers. Therefore, with an aim to improve the transient and steady state performance of linear controllers, in this paper, a nonlinear control framework using circle criterion method and saturation nonlinearity, which adjusts the integral gain based on the error threshold, is discussed. The global asymptotic stability (GAS) of the MLNC strategy is theoretically proved using LaSalle's invariance principle and experimentally validated using measured frequency response function (FRF). Moreover, the performance of the MLNC strategy is compared with that of the multi-loop linear control (MLLC) strategy on a benchmark magnetic levitation system for tracking application. The cumulative power spectral density (CPSD) of tracking error, which is used as the performance index to assess the overall closed loop performance, accentuates that MLNC can yield better steady state and transient performance compared to MLLC scheme.

OBJECTIVE

This study examined the impact of trabeculectomy on the central visual field in patients in which field loss threatens fixation.

METHODS

Fifty eyes in 45 patients demonstrating a visual field loss threat to fixation underwent trabeculectomy. All patients underwent visual field assessment before and within two months of surgery, using both the 24-2 quantitative program on the Humphrey Field Analyser, and the macular program which measures the threshold sensitivity three times per 16 points distributed in the central 5 degrees centrally at 2 degrees intervals. For inclusion in the study, each eye had to show involvement of at least two contiguous points in the central macular program, with a decrease in sensitivity to 15 dB or less, in a quadrant corresponding to a well-defined visual field defect shown on program 24-2.

RESULTS

The average post-operative follow-up was 7.1 months (+/- 5.52). Overall intraocular pressure reduction was 40%. Visual acuity decreased on an average of half line. None of the eyes showed loss of fixation. The average number of points with decreased sensitivity in the central 5 degrees (15 dB sensitivity or less) was 6.06 points (+/- 3.36) pre-operatively and 5.78 points (+/- 3.85) post-operatively (p = NS). Mean Defect (MD) was noted to decrease by 1 dB (p = 0.0295) whereas Corrected Pattern Standard Deviation (CPSD) and Foveal Sensitivity (FS) was essentially stable.

CONCLUSIONS

Based on the study, it appears that trabeculectomy can be safely offered to patients for surgical reduction of intraocular pressure even in those cases where central fixation is threatened by loss of vision within the five degrees of fixation.

Couplings between uterine contractions (UC) and fetal heart rate (fHR) provide important information on fetal condition during labor. At present, couplings between UC and fHR are assessed by visual analysis and interpretation of cardiotocography. The application of computerized approaches is restricted due to the non-stationarity of the signal, missing data and noise, typical for fHR. Herein, we propose a novel approach to assess couplings between UC and fHR, based on a signal-processing algorithm termed bivariate phase-rectified signal averaging (BPRSA).

METHODS

Electrohysterogram (EHG) and fetal electrocardiogram (fECG) were recorded non-invasively by a trans-abdominal device in 73 women at term with uneventful singleton pregnancy during the first stage of labor. Coupling between UC and fHR was analyzed by BPRSA and by conventional cross power spectral density analysis (CPSD). For both methods, degree of coupling was assessed by the maximum coefficient of coherence (CPRSA and CRAW, respectively) in the UC frequency domain. Coherence values greater than 0.50 were consider significant. CPRSA and CRAW were compared by Wilcoxon test.

RESULTS

At visual inspection BPRSA analysis identified coupled periodicities in 86.3% (63/73) of the cases. 11/73 (15%) cases were excluded from further analysis because no 30 minutes of fECG recording without signal loss was available for spectral analysis. Significant coupling was found in 90.3% (56/62) of the cases analyzed by BPRSA, and in 24.2% (15/62) of the cases analyzed by CPSD, respectively. The difference between median value of CPRSA and CRAW was highly significant (0.79 [IQR 0.69-0.90] and 0.29 [IQR 0.17-0.47], respectively; p<0.0001).

CONCLUSIONS

BPRSA is a novel computer-based approach that can be reliably applied to trans-abdominally acquired EHG-fECG. It allows the assessment of correlations between UC and fHR patterns in the majority of labors, overcoming the limitations of non-stationarity and artifacts. Compared to standard techniques of cross-correlations, such as CPSD, BPRSA is significantly superior.

BACKGROUND

Methadone maintenance treatment (MMT) has been shown to be an effective therapeutic strategy for opioid users. This study aimed to investigate the predictive effect of clinically predominant sleep disturbance (CPSD) on the dose of methadone among opiate users receiving MMT during a follow-up period of 6 years in Taiwan.

METHODS

This retrospective study included 1,290 individuals with opioid dependence who visited our MMT clinic for the first time. Generalized estimating equations were used to analyze the effect of CPSD on the daily dose of methadone by controlling for the effects of demographic and MMT characteristics.

RESULTS

A total of 469 (36.4%) participants were comorbid with CPSD. After controlling for the effects of demographic and MMT characteristics, the participants comorbid with CPSD had a higher dose of daily methadone than those without CPSD (estimate: 7.03, p < .001). Furthermore, younger age (estimate: -1.22, p < .001), older age at initial MMT (estimate: .44, p < .001), lower educational level (estimate: -.90, p = .003) and lower attendance rates (estimate: -.14, p = .033) are significantly related to higher doses of daily methadone.

CONCLUSIONS

Our study provided a naturalistic observation of the cohort for long period, along with a large sample size which could reflect clinical practice in the real world. We reported that a higher daily dose of methadone was significantly associated with CPSD after controlling for the effects of other factors. CPSD should be routinely surveyed among heroin users receiving MMT. (Am J Addict 2018;27:225-230).

OBJECTIVE

The authors noted an underestimation of the mean deviation for field testing using the Fastpak (Humphrey Instruments, San Leandro, CA) strategy, and set out to define the extent of this difference.

METHODS

Sixty-seven eyes of 35 glaucomatous patients were examined. Patients received full-threshold 24-2 tests before and after the Fastpak strategy was used, each test on a different day. For some patients, another full-threshold test was performed using a different birth date in order to obtain a result uninfluenced by prior data.

RESULTS

The mean deviation (MD) was significantly underestimated by Fastpak compared with the full-threshold tests. The time taken for Fastpak was almost identical to that taken for full-threshold tests. Short-term fluctuation (SF) appeared to have very little reliability statistically, and, consistent with this, there was a greater concordance among pattern standard deviation (PSD) data than among corrected pattern standard deviation (CPSD) data.

CONCLUSIONS

Fastpak was an effective method for charting the visual field, but did so with greater variation than full-threshold tests. It significantly underestimated the MD, and this was not a fatigue effect. Fastpak was no faster than full-threshold testing in advanced glaucoma. CPSD was a less consistent reading than PSD in these glaucomatous patients.

This study reports a ≅12.5 kDa protein tetrachloro-1,4-benzoquinone reductase (CpsD) from Bacillus cereus strain AOA-CPS1 (BcAOA). CpsD is purified to homogeneity with a total yield of 35% and specific activity of 160 U·mg^-1 of protein. CpsD showed optimal activity at pH 7.5 and 40 °C. The enzyme was found to be functionally stable between pH 7.0-7.5 and temperature between 30 °C and 35 °C. CpsD activity was enhanced by Fe²⁺ and inhibited by sodium azide and SDS. CpsD followed Michaelis-Menten kinetic exhibiting an apparent v_max, K_m, k_cat and k_cat/K_m values of 0.071 μmol·s^-1, 94 μmol, 0.029 s^-1 and 3.13 × 10^-4 s^-1·μmol^-1, respectively, for substrate tetrachloro-1,4-benzoquinone. The bioinformatics analysis indicated that CpsD belongs to the PCD/DCoH superfamily, with specific conserved protein domains of pterin-4α-carbinolamine dehydratase (PCD). This study proposed that CpsD catalysed the reduction of tetrachloro-1,4-benzoquinone to tetrachloro-p-hydroquinone and released the products found in phenylalanine hydroxylation system (PheOHS) via a Ping-Pong or atypical ternary mechanism; and regulate expression of phenylalanine 4-monooxygenase by blocking reverse flux in BcAOA PheOHS using a probable Yin-Yang mechanism. The study also concluded that CpsD may play a catalytic and regulatory role in BcAOA PheOHS and pentachlorophenol degradation pathway.

Keywords: Phenylalanine 4-monooxygenase; Phenylalanine hydroxylating system; Ping-Pong mechanism; Pterin-4α-carbinolamine dehydratase; Tetrachloro-1,4-benzoquinone reductase.

To know the pattern of visual field (VF) defect of low tension glaucoma (LTG), its diffuse and localized VF defects were compared using the significance values (p-value) of mean deviation (MD) and corrected pattern standard deviation (CPSD), which are calculated with STATPAC in Humphrey Visual Field Analyser. Sixteen eyes of LTG were enrolled and 34 eyes of primary open angle glaucoma (POAG) were used as controls. The degree of VF defects in LTG and POAG was relatively mild with the p-value of MD equal to or greater than 1%. Neither mean MD nor mean CPSD of LTG was significantly different from each of POAG (p>> 0.8 and p>> 0.2, respectively). Comparing the p-values of MD and CPSD, many patients showed more significant p-value of MD in LTG and POAG (62.5% and 61.8%, respectively). However, relatively more severe defect of CPSD tended to occur more frequently in LTG than in POAG (25% and 5.9%, respectively, chi 2 = 4.964, p < 0.09). The relation between p-values of MD and CPSD was not significantly influenced by the intraocular pressure, MD or vertical cup to disc ratio in either LTG or POAG.

OBJECTIVE

To study an influence of combined methods of rehabilitation for recovery of motor functions in patients with cerebral palsy with spastic diplegia (CPSD).

METHODS

Seventy-six patients with CPSD, aged from 14 to 19 years (mean age 18.7±4.63 years), were under observation. A comprehensive clinical and instrumental examination was conducted. Patients of the main group received a course of underwater spinal traction with the introduction of the drug cellex along with Spa treatment. Patients of the comparison group received only Spa treatment.

CONCLUSIONS

Signs of involvement of segmental structures of the nervous system in the pathological process and their role in the formation of motion pathology are established. It is shown that the inclusion of underwater traction according to the original technique and simultaneous introduction of cellex in the complex of rehabilitation measures allows to achieve a pronounced positive dynamics in the form of expansion of motor capabilities of patients with cerebral palsy. There was a significant decrease in spastic muscle tone, restoration of the volume of movements in the joints, improved walking. Positive clinical dynamics was correlated with EMG data.

In cluster perturbation (CP) theory, we consider a target excitation space relative to a Hartree-Fock state and partition the target excitation space into a parent excitation space and an auxiliary excitation space. The zeroth-order state is in CP theory a coupled cluster (CC) state in the parent excitation space, and the target state is a CC state in the target excitation space. In this paper, we derive CP series for excitation energies in orders of the CC parent-state similarity-transformed fluctuation potential where the zeroth-order term in the series is an excitation energy for the CC parent state response eigenvalue equation and where the series formally converge to an excitation energy for the CC target state response eigenvalue equation. We give explicit expressions for the lowest-order excitation energy corrections. We also report calculations for CP excitation energy series for various parent and target excitation spaces and examine how well the lower-order corrections can reproduce the total excitation energies. Considering the fast local convergence we have observed for the CP excitation energy series, it becomes computationally attractive to use low-order corrections in CP series to obtain excitation energies of CC target state quality. For the CPS(D-n) series, the first-order correction vanishes, the second-order correction becomes the CIS(D) model, and for the CPS(D-3) model, our calculations suggest that excitation energies of CCSD quality are obtained. The numerical results also suggest that a similar behavior can be seen for the low-order excitation energy corrections for CP series where the parent state contains more than a singles excitation space, e.g., for the CPSD(T) model. We therefore expect the low-order excitation energy corrections in CP series soon to become state-of-the-art models for determining excitation energies of CC target state quality.

The advances in electrocardiographic (ECG) technology have facilitated the development of numerous successful clinical applications and commercial monitoring products for diagnosing disease and monitoring health. All of these demand the development of smart algorithms and computational resources for the real-time, early indication of critical cardiac conditions. This study presents the development of a Complex Phase Space Difference (CPSD) algorithm with differential method to analyze spatial and temporal changes in reconstructed phase space matrix, and derives an index for real-time monitoring. We used total of 5306 data segments from MIT-BIH, CU, and SCDH databases and clinical trial data to determine the optimal working parameters and verified the classification capability by using a quantitative index of this algorithm. With threshold values set to 2.0 and 6.0, this method can successfully differentiate normal sinus rhythm (NSR) signals (1.48+/-0.21), low risk of atrial fibrillation (AF) signals (3.71+/-0.99) and high risk of ventricular fibrillation (VF) signals (9.38+/-2.22). It is the first real-time algorithm that reports the best performance to distinguish AF and VF with sensitivity of 97.9% and specificity of 98.4%. With self-normalization, the algorithm is not subjected to the inter-variability or sampling size effects. Its computational scheme only requires matrices addition and subtraction, and thus significantly reduces the complexity for real-time implementation. It will be able to adopt in different scenarios of tele-healthcare and implantable applications.

OBJECTIVE

To describe the implementation process of a Clinical Practice Protocol for Patients with Swallowing Disorders (CPSD) in a public hospital of high technological density in the Federal District of Brazil.

METHODS

This is an Experience Report study which describes the implementation process of a Clinical Practice Protocol for Patients with Swallowing Disorders in a public hospital of high technological density in the Federal District.

RESULTS

The protocol was implemented in three stages: Stage 1 - literature search on the procedures that characterize the best propaedeutic and therapeutic practices; Stage 2 - discussion with a multidisciplinary team about the adjustments needed to implement the CPSD; and Stage 3 - Final proposal for the protocol implementation considering the particularities of the service.

CONCLUSIONS

The final proposal of the Clinical Practice Protocol for Patients with Swallowing Disorders (CPSD) provides a predefined, systematic method to monitor patients with swallowing disorders in high technological density health facilities. In addition to being inexpensive, the CPSD fosters decision-making, favors early detection of disorders, and assists managers with evaluating the quality of the service offered.

Chinese medicine is a national treasure that has been passed down for thousands of years in China. According to the statistics of the World Health Organization, there are currently four billion people in the world who use Chinese medicine to treat diseases, accounting for 80% of the world's total population. However, the obscurity of its theory, its unmanageable quality, its complex compositions, and the unknown effective substances and mechanisms are great obstacles to the internationalization of Chinese medicine. Here, we propose a new strategy for the development of Chinese medicine: the clinical prescription (C)-protein (P)-small-molecule (S)-disease (D) strategy, namely the CPSD strategy. The strategy uses clinical prescriptions as the source of medicine and uses computer simulation technology to find small-molecule drugs targeting therapeutic proteins for treating specific diseases so as to deepen awareness of the value of Chinese medicine. At the same time, this article takes cardiovascular drug development as an example to introduce the application of CPSD, which will be instrumental in the further development, modernization, and internationalization of Chinese medicine.

OBJECTIVE

The authors compare the results of the Dicon suprathreshold, kinetic fixation perimeter with multiple stimulus presentation to automated threshold perimetry (Humphrey) in the same eye.

METHODS

A Dicon screening visual field test and a Humphrey threshold visual field test were performed in 148 eyes of 148 persons with glaucoma or who were suspect for glaucoma. The number and pattern of missed points on the Dicon test were compared with Humphrey global indices in each eye.

RESULTS

The median time to complete the 40-point, Dicon suprathreshold test was 2.7 minutes per eye. Regression analyses indicated that Dicon test parameters were modestly correlated with Humphrey corrected pattern standard deviation (CPSD) probability and mean deviation (R2 ranging from 0.21 to 0.46, p = 0.000). With glaucoma defined as a Humphrey Glaucoma Hemifield Test (GHT) result of outside normal limits, the best mix of sensitivity and specificity of Dicon results occurred at 2 or more missed points, with sensitivity of 64% and specificity of 83%. The specificity was maximum (90%) with a Dicon criterion of 3 or more adjacent missed points, but sensitivity at this level was 55%. With glaucoma defined by CPSD probability value less than 1%, sensitivity and specificity for two adjacent missed Dicon points were 69% and 87%, respectively.

CONCLUSIONS

Dicon suprathreshold testing is a practical means to differentiate between some persons with glaucomatous damage and glaucoma suspects.

We compared the results of visual field examination obtained with a Humphrey 30-2 program between 57 eyes of 57 low-tension glaucoma (LTG) and 57 eyes of 57 primary open-angle glaucoma (POAG; max IOP>> or = 25 mmHg) cases, whose mean deviation (MD) given by STATPAC was>> -10 dB. MD, age, and refraction showed no differences between the two groups. Corrected pattern standard deviation (CPSD) was significantly higher in the LTG group (p < 0.01). The total deviation (TD), deviation from the age-corrected normal reference, was found to be significantly lower by about 5 dB in the LTG group at two test points nasal-superior to the fixation point (Wilcoxon rank sum test, p < 0.01). Logistic discriminant analysis carried out to exclude a subtle difference in the distribution of the stage of disease between the two groups confirmed a significant between-group difference at the above-mentioned points. Furthermore, to compare the unevenness of visual field in the two groups, [TD-mean TD] was calculated, where mean TD was the average of 70 points of TD excluding the uppermost four points, and the same two points obtained above were found to decrease significantly in LTG, while all points were diffusely damaged in POAG. These results may imply a difference in the mechanism of visual field damage between LTG and POAG.

A prospective, randomized study was conducted to survey a large number of automated perimetry examinations in a central reading institute, obtaining practical information on unselected referred patients and their clinician "consumers". Visual field records of 1041 patients were obtained, each evaluated by one of three glaucoma specialists. Statistical analysis was applied on demographics, physician characteristics, test reliability and visual field scores. Reliability was scored on a scale of 1 (excellent) to 5 (uninterpretable). Data from earlier examinations of these patients was also analyzed. The large majority of patients (70.4%) were referred due to glaucoma, ocular hypertension or suspected glaucoma. Most of the patients had threshold strategies: FastPac 24-2 or 30-2 (88.9%), Full Threshold (0.7%), and 10-2 (0.5%). In only 7 patients was short-wavelength automated perimetry (SWAP) performed. The Swedish Interactive Testing Algorithm (SITA) was applied in 1.0% of cases. More than half (56.8%) of the population had a reliability score of 1, and 22.7% had a score of 2, indicating a valid result for 79.4% of patients, providing clinically useful information. Linear regression analyses indicated that the Mean Defect was a better predictor of the visual field score than the Corrected Pattern Standard Deviation (CPSD), for the entire group and for each visual field score subgroup.

Glaucoma is a progressive optic neuropathy characterized by damage of the retinal ganglion cells and their axons and glial cells. The aim of this study was to evaluate the differences and connections between changes in the visual field and the thickness of the peripapillary retinal nerve fiber layer (RNFL), using optical coherence tomography (OCT) in patients with primary open-angle glaucoma with normal and elevated intraocular pressure (IOP).

This prospective study included 38 patients (38 eyes) with primary open-angle glaucoma with normal intraocular pressure (NTG) and 50 patients (50 eyes) with primary open-angle glaucoma with elevated intraocular pressure (HTG), paired by the same degree of structural glaucomatous changes in the optic nerve head and by age. OCT protocols ’fast RNFL thickness’ and ’fast optic disc’ were used for testing. The patients’ age, gender, best corrected visual acuity (BCVA), IOP, stereometric and functional parameters were compared.

The average age of the examined population was 65.49 ± 9.36 (range 44-83) years. There was no statistically significant difference by age and by gender between the two study groups (p = 0.795 and p = 0.807, respectively). BCVA was higher in patients with NTG but there was no statistically significant difference compared to HTG patients (p = 0.160). IOP was statistically significantly higher in patients with HTG compared to NTG patients (17.40 ± 2.77 mmHg vs 14.95 ± 3.01 mmHg, p = 0.009). The cup/disc (C/D) (p = 0.258), mean deviation (MD) (p = 0.477), corrected patern standard deviation (CPSD) (p = 0.943), disk area (p = 0.515), rim area (p = 0.294), rim volume (p = 0.118), C/D area R (p = 0.103), RNFL Average (p = 0.632), RNFL Superior (p = 0.283) and RNFL Inferior (p = 0.488) were not statistically significantly different between the groups.

OCT measurements of the RNFL thickness provide clinically significant information in monitoring of glaucomatous changes. There are no differences in the patterns of RNFL defects per sectors and quadrants between NTG and HTG, measured by OCT.

BACKGROUND

In order to ascertain whether the optic disc surface smoothness (ODSS) could be used to predict the amount of visual field damage in glaucomatous eyes, the correlations between ODSS and visual field indices were evaluated.

METHODS

One eye was randomly chosen from each of 40 normals and 50 patients with glaucoma. The morphology of the optic disc surface was analyzed using the Topcon IMAGEnet X Rev-3.51b. In order to define the level of "smoothness" of the optic disc surface, the differences of the relative position of each surface point was studied by measuring the standard deviation (SD) from the average height of the points (number of points ranged from 623 to 1883 depending on the size of the disc area) that identify the optic disc surface. All the subjects were also examined with the Humphrey perimeter (Program 30-2) and the results were analyzed by Mann-Whitney U-test and Spearman rank correlation coefficient.

RESULTS

The difference in ODSS between the glaucomatous and the normal eyes was statistically significant. No significant correlation was found between age and ODSS. A significant correlation was found between ODSS and mean deviation (MD) and between ODSS and corrected pattern standard deviation (CPSD). In the glaucoma group there were significant correlations between ODSS and the perimetric indices MD and CPSD; no correlations were found in the normal group.

CONCLUSIONS

The ability of ODSS to reflect the level of visual field change in glaucomatous eyes appears to be rather limited, even if statistically significant. This fact does not limit the clinical usefulness of ODSS as a diagnostic parameter in consequence of its strong correlations with the other morphometric parameters and its high sensitivity and specificity in separating normal from glaucomatous eyes.

OBJECTIVE

To determine the correlation between the structural changes in the Retinal Nerve Fiber Layer (RNFL) and functional losses detected with ShortWavelength Automated Perimetry (SWAP) in a population of patients with suspected glaucoma.

METHODS

49 eyes of 49 ocular hypertensive subjects who met the selection criteria (intraocular pressure greater than 21 mm of Hg and normal standard visual fields) were studied. SWAP was performed with a modified Humphrey Field Analyzer. Visual field indexes (MD, CPSD) were calculated for SWAP. Semiquantitative RNFL scores were given separately to diffuse and localized defects of the RNFL.

RESULTS

The MD increased significantly (p<0.001) with higher Diffuse and Total RNFL scores, with good correlation coefficients. A small correlation was found between the CPSD and the RNFR scores (Diffuse, Total and Localized RNFL scores).

CONCLUSIONS

Diffuse retinal nerve fiber layer losses are associated with diffuse field loss (MD) while focal structural damage showed no correlation with visual field losses.

OBJECTIVE

To evaluate the diagnostic ability of the Moorfields regression analysis (MRA; neuroretinal rim sector-based analysis) by means of confocal scanning laser.

METHODS

200 eyes were included in this study: 101 normal subjects and 99 glaucoma patients (standard automated perimetry with glaucomatous defects -MD or CPSD with p<0.02 or a cluster of three or more points with p<0.05 or a cluster of two or more points with p<0.01 or abnormal Glaucoma Hemifield Test). All subjects underwent a full ophthalmic evaluation, visual field evaluation by means of a Humphrey Field Analyzer, 24-2 full threshold strategy, and optic disc topography by Heidelberg retina tomograph (HRT-II). The outcome parameters were sensitivity and specificity of the MRA for each sector.

RESULTS

The highest sensitivity in detecting structural defects based on MRA (p<0.05) was observed in the nasal-superior sector (48%) and nasal-inferior sector (45%); however the highest specificity was found in the temporal-superior (98%) and inferior (98%) sectors. The highest sensitivity for MRA (p<0.01) was found in the temporal-inferior sector (31%) and nasal-superior sector (30%) while the temporal-superior and inferior-sectors showed the highest specificity (100%). The diagnosis of glaucoma based on the presence of any sector alteration showed sensitivity figures of 67% with p<0.05 and 46% with p<0.01 and specificity values of 84% with p<0.05 and 96% with p<0.01.

CONCLUSIONS

The analysis of the distribution of the neuroretinal rim by means of HRT-II contributes effectively to the diagnosis of glaucoma based on perimetry in a sample derived from a Spanish population.

OBJECTIVE

This study was conducted to determine the correlation between structural changes in the retinal nerve fiber layer (RNFL) and functional loss detected on short-wavelength automated perimetry (SWAP) in a population of patients with suspected glaucoma.

METHODS

With a selection criteria of intraocular pressure (IOP) more than 21 mmHg and normal results of conventional automated perimetry, 49 eyes of 49 patients with ocular hypertension were enrolled in the study. The SWAP was performed with a modified Humphrey field analyzer, and visual field indexes (mean deviation [MD], corrected pattern standard deviation [CPSD]) were calculated. Semiquantitative RNFL scores were given separately to diffuse and localized defects of the RNFL.

RESULTS

The MD increased significantly with higher diffuse and total RNFL scores, with good correlation coefficients. A weak correlation was found between CPSD and diffuse, total, and localized RNFL scores.

CONCLUSIONS

Diffuse RNFL loss are associated with abnormalities in visual field indexes (MD), whereas focal structural damage showed no correlation with visual field loss.

A cross-over double-blind study was performed to evaluate the effect of acute administration of brimonidine on the blue-yellow perimetry. Thirty patients with primary open-angle glaucoma were admitted. After brimonidine administration, IOP and pupil diameter showed a significant reduction (p < 0.01) without modification in systolic and diastolic blood pressure. Blue-on-yellow perimetry showed a significant reduction in CPSD from 3.81 +/- 1.60 to 2.71 +/- 1.92 (p < 0.05). This result suggests that brimonidine improves ocular perfusion via a reduction of IOP.

The authors prospectively studied changes in the optic disc and visual field associated with intraocular pressure (IOP) reduction for one year after surgery in 12 primary open-angle glaucoma eyes of 7 patients who underwent trabeculectomy because of elevated IOP despite maximum tolerable medical therapy and whose cup volume was demonstrated to be decreased at 3 or 6 months after surgery. Topographic parameters including C/D ratio, rim area and cup volume were determined by the Optic Nerve Head Analyzer plus (Rodenstock). The 30-2 central threshold field was obtained with a Humphrey Field Analyzer at the same time. Mean deviation (MD), corrected pattern standard deviation (CPSD) and total deviation (TD) were used to evaluate visual field changes. Significant improvement of C/D ratio, rim area and cup volume and significant IOP reduction were noted at 1 year after surgery as compared with preoperative baseline value (p less than 0.01). Also the MD was significantly decreased at 1 year after surgery, compared with the preoperative baseline value (p less than 0.05). There was a significant negative correlation between the preoperative MD and the percent change of the MD at 1 year after surgery (r = -0.80, p less than 0.01). Our results suggest that the decrease of optic disc cupping can persist over one year after surgery and that the early visual field defects in glaucoma eyes can gradually improve in association with the decrease of cupping.

Life-threatening ventricular arrhythmias remain the main cause of death among patients with cardiovascular diseases. Efforts have been spent on early detection of such fatal cardiac signs. We have previously reported a novel chaotic phase space differential (CPSD) algorithm in discriminating VPC, VT, and VF from normal sinus rhythm with both good sensitivity and specificity. In this article, we apply this algorithm on the rat model of calcium induced ventricular tachycardia. Peaked CPSD values can be observed along with the occurrence of ventricular tachycardia. In addition, minor ECG changes such as new onset S wave or sinus arrhythmia can also be noted on CPSD tracing. We believe that the CPSD algorithm not only is capable of detecting lethal ventricular arrhythmias, but also is potentially a good tool for long-term monitoring the change of ECG signals.