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Purpose The goal of this work was to (i) determine patterns of progression in glaucomatous visual field loss, (ii) compare the detection rate of progression between locally condensed stimulus arrangements and conventional 6° × 6° grid, and (iii) assess the individual frequency distribution of test locations exhibiting a local event (i.e., an abrupt local deterioration of differential luminance sensitivity (DLS) by more than -10dB between any two examinations). Methods The visual function of 41 glaucomatous eyes of 41 patients (16 females, 25 males, 37 to 75 years old) was examined with automated static perimetry (Tuebingen Computer Campimeter or Octopus 101-Perimeter). Stimuli were added to locally enhance the spatial resolution in suspicious regions of the visual field. The minimum follow-up was four subsequent sessions with a minimum of 2-month (median 6-month) intervals between each session. Progression was identified using a modified pointwise linear regression (PLR) method and a modified Katz criterion. The presence of events was assessed in all progressive visual fields. Results Eleven eyes (27%) showed progression over the study period (median 2.5 years, range 1.3–8.6 years). Six (55%) of these had combined progression in depth and size and five eyes (45%) progressed in depth only. Progression in size conformed always to the nerve fiber course. Seven out of 11 (64%) of the progressive scotomata detected by spatially condensed grids would have been missed by the conventional 6° × 6° grid. At least one event occurred in 64% of all progressive eyes. Five of 11 (46%) progressive eyes showed a cluster of events. Conclusions The most common pattern of progression in glaucomatous visual fields is combined progression in depth and size of an existing scotoma. Applying individually condensed test grids remarkably enhances the detection rate of glaucomatous visual field deterioration (at the expense of an increased examination time) compared to conventional stimulus arrangements.

Background Robot-assisted laparoscopic augmentation ileocystoplasty with Mitrofanoff appendicovesicostomy (RALIMA) may protect the upper urinary tract and reestablish continence in patients with refractory neurogenic bladder. Robotic assistance can provide the benefits of minimally invasive surgery without the steep learning curve of pure laparoscopy. Objective To highlight the interim outcomes of RALIMA with salient tips and technical modifications through comparison with patients undergoing open augmentation ileocystoplasty (OAI). Design, settings, and participants A retrospective chart review of 17 patients undergoing robot-assisted laparoscopic augmentation ileocystoplasty (RALI) and 13 patients undergoing OAI by a single surgeon at an academic center from 2008 to 2012 (OAI) or 2014 (RALI). Surgical procedure RALI and all concomitant procedures were performed completely intracorporeally using the da Vinci surgical system (Intuitive Surgical, Inc., Sunnyvale, CA, USA). Outcome measurements and statistical analysis Outcomes of interest included change in bladder capacity, operative time, pain medication use, hospitalization time, and perioperative complication rates. Results and limitations Of 17 patients selected, 15 successfully underwent RALI. Overall, 11, 6, and 4 patients had a concomitant Mitrofanoff appendicovesicostomy, antegrade colonic enema channel, and bladder neck closure, respectively. The median operative time was significantly longer in RALI (623 vs 287min; p p =0.01). The postoperative percentage increase in bladder capacity, narcotic use, and complication rates did not differ between RALI and OAI. Limitations include the retrospective study design and the small cohort of patients. Conclusions RALI appears to offer functional outcomes similar to OAI. Although it is a significantly longer procedure, it may decrease LOS and avoid epidural use. Further refinements may reduce operative time. Patient summary In this report, we examined outcomes after robotic bladder augmentation surgery in children. We found that the robotic approach may eliminate epidural analgesia use and decrease hospitalization time after surgery.

Background: To evaluate the effect of response-acquisition technique on psychometric performance in visual-field testing, the conventional one-button yes/time-out method was compared with a two-button yes/no method for responding whether or not the stimulus was detected. There are a number of situations in which the single-button technique leads to ambiguous results. In this study, we thus expected the yes/no method to reduce tendencies towards habituation and automatic responding. Our hypothesis was that the two-button technique could reduce the rate of erroneous responses. Methods: Luminance-difference sensitivity for bright stimuli (32') on a photopic background was evaluated at 26 locations within the central visual field (30°) using a specially equalised video display unit and a modified 4/2-dB staircase strategy (six reversals, maximum-likelihood threshold estimation). Sixty-one ophthalmologically normal subjects (aged 20–30 years) were examined twice with each method. Results: Mean sensitivities with the two-button yes/no method were found to be, on average, 0.13 dB above those measured with the one-button yes/time-out technique – a difference without clinical relevance. Within-subject variability did not differ between the two methods. However, the less intuitive two-button yes/no method had a slightly higher number of false responses in catch trials. Conclusion: Compared to the conventional one-button yes/time-out method, the two-button yes/no method in normal young subjects thus showed little difference in mean sensitivities and equivalent within-subject variabilities. Concerning our initial hypothesis, the yes/no method is of somewhat higher complexity and is not able to reduce the rate of erroneous responses. The one-button yes/time-out method fared a little better in error rate. In summary, the yes/no method is an alternative and additional possibility of response acquisition in visual-field testing, which is worthy of being tested in a clinical study with elderly subjects.

Fundus-oriented perimetry (FOP) was used to evaluate the effectiveness of different-sized bright and dark stimuli in detecting and quantitatively measuring angioscotoma. The foveolas and optic disks of digitized fundus images were aligned with their psychophysical counterparts to construct individual grids of perimetric stimuli. Each grid included a linear set of test point locations crossing a retinal vessel. Angioscotomas immediately became visible in nine of 13 healthy normal volunteers tested with FOP. Additional mathematical processing of local loss of differential light sensitivity (dls) disclosed an angioscotoma for at least one stimulus condition in all persons tested. The angioscomas were usually deeper for small (12′) targets than for large (32′) ones. On the other hand, the overall noise at dls thresholds was generally higher for small than for large stimuli regardless of whether the stimuli were bright or dark. No noteworthy differences were found in detection rates or signal-to-noise ratios under different stimulus conditions (dark/bright/small/large). FOP permits the individual arrangement of stimuli for specific morphological conditions and is thus capable of detecting even minute visual field defects such as angioscotomas.

This paper presents a new automated method for analyzing compression wood fibers in fluorescence microscopy. Abnormal wood known as compression wood is present in almost every softwood tree harvested. Compression wood fibers show a different cell wall morphology and chemistry compared to normal wood fibers, and their mechanical and physical characteristics are considered detrimental for both construction wood and pulp and paper purposes. Currently there is the need for improved methodologies for characterization of lignin distribution in wood cell walls, such as from compression wood fibers, that will allow for a better understanding of fiber mechanical properties. Traditionally, analysis of fluorescence microscopy images of fiber cross-sections has been done manually, which is time consuming and subjective. Here, we present an automatic method, using digital image analysis, that detects and delineates softwood fibers in fluorescence microscopy images, dividing them into cell lumen, normal and highly lignified areas. It also quantifies the different areas, as well as measures cell wall thickness. The method is evaluated by comparing the automatic with a manual delineation. While the boundaries between the various fiber wall regions are detected using the automatic method with precision similar to inter and intra expert variability, the position of the boundary between lumen and the cell wall has a systematic shift that can be corrected. Our method allows for transverse structural characterization of compression wood fibers, which may allow for improved understanding of the micro-mechanical modeling of wood and pulp fibers.

Fundus-oriented perimetry (FOP) was used to evaluate the effectiveness of different-sized bright and dark stimuli in detecting and quantitatively measuring angioscotoma. The foveolas and optic disks of digitized fundus images were aligned with their psychophysical counterparts to construct individual grids of perimetric stimuli. Each grid included a linear set of test point locations crossing a retinal vessel. Angioscotomas immediately became visible in nine of 13 healthy normal volunteers tested with FOP. Additional mathematical processing of local loss of differential light sensitivity (dls) disclosed an angioscotoma for at least one stimulus condition in all persons tested. The angioscomas were usually deeper for small (12) targets than for large (32') ones. On the other hand, the overall noise at dls thresholds was generally higher for small than for large stimuli regardless of whether the stimuli were bright or dark. No noteworthy differences were found in detection rates or signal-to-noise ratios under different stimulus conditions (dark/bright/small/large). FOP permits the individual arrangement of stimuli for specific morphological conditions and is thus capable of detecting even minute visual field defects such as angioscotomas.

Maintaining the position of a guidewire across coronary artery lesions during angioplasty is important to allow rapid and reliable access. Stabilizing these small caliber angioplasty guidewires during guide catheter replacement is often difficult, if not impossible at times. This article reviews the techniques for exchanging guide catheters while maintaining coronary guidewire position. It also introduces the bi-coaxial guide catheter exchange technique.

Early identification and treatment, including administration of intravenous thrombolytics, coronary angioplasty, and adjunctive therapies, has been shown to benefit patients who present with acute myocardial infarction. However, only a small percentage of these patients receive such therapies because of late presentation, associated risks, and controversies around certain myocardial infarct subsets. The logistics involved in carrying out these treatments have resulted in unnecessary prehospital and in-hospital delays. These issues make essential the availability of a streamlined protocol that should be updated at regular intervals to ensure that these time-dependent therapies are more routinely and rapidly utilized. This article discusses these topics in conceptual format and provides a ready-to-use protocol.

Pericardial interventions for the diagnosis and treatment of pericardial disease has been evolving since the 17th century. The controversy over opened or closed procedures, the optimal guidance modality, and techniques for the creation of pericardial windows continues to be debated. This report describes two patients who the endoscopic approach to creating a pericardial window. © Wiley-Liss, Inc.

Coronary artery anomalies occur infrequently compared to atherosclerotic disease; however, when they do occur, they can pose difficulty with coronary visualization and identification. Ectopic origin of the left mainstem coronary artery from the right sinus of Valsalva coursing between the great vessels is the rarest subtype of these anomalies, can be potentially serious, and presents unique problems for surgical treatment.

To assess the spatial distribution of glaucomatous visual field defects (VFDs) obtained with regionally condensed stimulus arrangements.Sixty-three eyes of 63 glaucoma subjects were examined with threshold-estimating automated static perimetry (full threshold 4-2-1 dB strategy with at least three reversals) on an automatic campimeter or a full-field perimeter. Stimuli were added by the examiner to regionally enhance spatial resolution in regions that were suspicious for a glaucomatous VFD. These regions were characterized by contiguous local VFDs, attributable to the retinal nerve fiber bundle course according to the impression of the examiner. The added stimulus locations were subsets of a predefined, dense perimetric grid. All VFD locations with P0.05 (total deviation plots) were assessed by superimposing the visual field records of all participants.Glaucomatous VFD loss occurred more frequently in the upper than in the lower hemifield, with a typical retinal nerve fiber-related pattern and a preference of the nasal step region. More than 50% of the eyes with predominantly mild to moderate glaucomatous field loss showed defective locations in the immediate superior paracentral region within an eccentricity of 3°.Conventional thresholding white-on-white perimetry with regionally enhanced spatial resolution reveals that glaucomatous visual field loss affects the immediate paracentral area, especially the upper hemifield, in many eyes with only mild to moderate glaucomatous visual field loss. Detailed knowledge about the spatial pattern and the local frequency distribution of glaucomatous VFDs is an essential prerequisite for creating regionally condensed stimulus arrangements for adequate detection and follow-up of functional glaucomatous damage.

PreviewOnly a small percentage of patients who have acute myocardial infarction receive the benefit of intravenous thrombolytic therapy, often because logistics result in unnecessary prehospital and in-hospital delays. Dr Selig therefore recommends that a streamlined protocol be available and that it be updated at regular intervals to ensure that this time-dependent therapy is more routinely utilized.

Fixed-wire (FW) coronary angioplasty procedures have gained widespread acceptance in some institutions as a primary choice for all angioplasty procedures. These single-lumen, low-profile devices provide distinct advantages as compared to over-the-wire systems in certain circumstances. However, they have not allowed for lesion protection or guidewire access if the situation arises. Two techniques are available to provide lesion protection during FW coronary angioplasty. They are the buddy wire technique and the use of subselective intracoronary access catheters. Access catheters can be used as primary, pre-loaded devices or as secondary devices to be used over an extended FW balloon catheter. These techniques can widen the applications of FW balloon angioplasty.

We developed a mathematical model wherein retinal nerve fiber trajectories can be described and the corresponding inter-subject variability analyzed. The model was based on traced nerve fiber bundle trajectories extracted from 55 fundus photographs of 55 human subjects. The model resembled the typical retinal nerve fiber layer course within 20 degrees eccentricity. Depending on the location of the visual field test point, the standard deviation of the calculated corresponding angular location at the optic nerve head circumference ranged from less than 1 degrees to 18 degrees, with an average of 8.8 degrees. (C) 2009 Elsevier Ltd. All rights reserved.