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Background Although many hair disorders can be readily diagnosed based on their clinical appearance, their progression and response to treatment are often difficult to monitor, particularly in quantitative terms. We introduce an innovative technique utilizing a smartphone and computerized image analysis to expeditiously and automatically measure and compute hair density and diameter in patients in real time. Methods A smartphone equipped with a dermatoscope lens wirelessly transmits trichoscopy images to a computer for image processing. A black-and-white binary mask image representing hair and skin is produced, and the hairs are thinned into single-pixel-thick fiber skeletons. Further analysis based on these fibers allows morphometric characteristics such as hair shaft number and diameters to be computed rapidly. The hair-bearing scalps of fifty participants were imaged to assess the precision of our automated smartphone-based device in comparison with a specialized trichometry device for hair shaft density and diameter measurement. The precision and operation time of our technique relative to manual trichometry, which is commonly used by hair disorder specialists, is determined. Results An equivalence test, based on two 1-sided t tests, demonstrates statistical equivalence in hair density and diameter values between this automated technique and manual trichometry within a 20% margin. On average, this technique actively required 24 seconds of the clinician's time whereas manual trichometry necessitated 9.2 minutes. Conclusion Automated smartphone-based trichometry is a rapid, precise, and clinically feasible technique which can significantly facilitate the assessment and monitoring of hair loss. Its use could be easily integrated into clinical practice to improve standard trichoscopy.

In order to provide an alternative for fresh frozen specimens to map the lymphatic system, the possibility of using Thiel embalmed specimens for this purpose was explored. The thoracic duct was used to investigate if retrograde injection of contrast agent was possible in Thiel embalmed specimens and to verify up to which diameter lymphatic vessels could be reconstructed and rendered in 3D, after CT scanning. 3D renderings were used for digital diameter measurement, to determine the smallest lymphatic diameter that could still be visualized on CT. Finally, the contrast agent concentration was adapted based on the findings during image reconstruction and 3D rendering. All Thiel embalmed specimens proved suitable for retrograde injection of contrast agent into the thoracic duct and all 3D renderings perfectly overlapped with the dissection pictures. The smallest diameter of contrast filled lymphatics that could be reconstructed and rendered in 3D was 0.23 mm. Increasing the concentration of barium sulphate from 10% to 50% reduced the post-processing time needed to render a ‘clean’ 3D structure, following automatic segmentation based on grey values, by 95%. The authors would recommend the use of Thiel embalmed specimens for mapping the lymphatic system, as these specimens do not show the rapid putrefaction that occurs in fresh frozen specimens, thus greatly facilitating experimental planning.

Background and purpose Optic nerve sheath diameter (ONSD) is used for the estimation of intracranial pressure (ICP). But there are still doubts about the quality of the images and the lateral resolution. Our aim is to investigate the system suitability and best lateral resolution of different ultrasound systems for acoustic ONSD measurement. Methods First, we calculated the theoretically lateral imaging resolution at increasing frequencies: 6.6, 10, and 15 MHz using two different ultrasound systems. Second, we created two phantoms consisting of copper wires or polyvinylchloride (PVC) strips and tested the best lateral resolution at different frequencies with the two ultrasound systems. Using the same ultrasound systems, we evaluated the anatomy of optic nerve at increasing transmission frequencies. Finally, the two probes were tested in two patients with different neurological conditions affected by an increase of ICP. Results Theoretical resolutions were .63, .43, and .41 mm, respectively, with a frequency of 6.6, 10, and 15 MHz. We found a similar lateral resolution in both phantoms: copper wire; .56 mm at 6.6 MHz, .46 mm at 10 MHz, and .44 mm at 15 MHz; and PVC strips .6 mm at 6.6 MHz, .47 mm at 10 MHz, and .40 mm at 15 MHz in accordance with experimental resolution. The ONSD thickening could be clearly displayed at frequencies higher than 7.5 MHz using the two linear probes and the two patients with an increase of ICP showed thickening of ONSD. Conclusion According to our study, both systems are suitable for ultrasound OSND measurement.

OBJECTIVES We present our experience with a novel method for real time co-registration of intravascular ultrasound (IVUS) and coronary angiography. BACKGROUND A major limitation of the current practice of concomitant use of coronary angiography and IVUS is that the locations of the acquired IVUS images are not correlated with their exact locations on the vessel roadmap obtained by coronary angiography. METHODS Phantoms simulating the coronary tree were used to test the accuracy and potential of co-registration. Subsequently we examined patients who underwent IVUS during cardiac catheterization. Analysis and feasibility were performed in 42 arteries of 36 patients. RESULTS The statistical validation in phantoms resulted in a co-registration accuracy of 1.12 mm. The length measurement on an angiogram resulted in an accuracy of 0.38 mm. Co-registration in patients was successful in all cases and four categories were assisted by 1(bad) to 5 (good) grading. Accuracy (the co-registration precision in pointing at the exact corresponding location): 4.8±0.41; Ease of use and workflow: 4.74±0.44; Stent landing zone detection and evaluation: 4.58±0.5; Stent landing zone length and diameter measurement: 4.94±0.23. The co-registration error was estimated as no more than 1 mm. CONCLUSION In this pilot study, we found that the novel IVUS and coronary angiography co-registration method is accurate, easy to use, fast and user-friendly. This method precludes the need to use motorized automated pull back device.

Tracheal collapse is a progressive airway disease that can ultimately result in complete airway obstruction. Intraluminal tracheal stents are a minimally invasive and viable treatment for tracheal collapse once the disease becomes refractory to medical management. Intraluminal stent size is chosen based on the maximum measured tracheal diameter during maximum inflation. The purpose of this prospective, cross-sectional study was to compare tracheal lumen diameter measurements and subsequent selected stent size using both fluoroscopy and CT and to evaluate inter- and intraobserver variability of the measurements. Seventeen healthy Beagles were anesthetized and imaged with fluoroscopy and CT with positive pressure ventilation to 20 cm H2 O. Fluoroscopic and CT maximum tracheal diameters were measured by three readers. Three individual measurements were made at eight predetermined tracheal sites for dorsoventral (height) and laterolateral (width) dimensions. Tracheal diameters and stent sizes (based on the maximum tracheal diameter + 10%) were analyzed using a linear mixed model. CT tracheal lumen diameters were larger compared to fluoroscopy at all locations (P-value < 0.0001). When comparing modalities, fluoroscopic and CT stent sizes were statistically different. Greater overall variation in tracheal diameter measurement (height or width) existed for fluoroscopy compared to CT, both within and among observers. The greater tracheal diameter measured with CT and lower measurement variability has clinical significance, as this may be the imaging modality of choice for appropriate stent selection to minimize complications in veterinary patients.

Standards for measuring the metacarpals are absent from commonly used osteometric guides. Perhaps the closest to a set of standard measurements in common use today are those proposed by Scheuer and Elkington (Scheuer and Elkington: J Forensic Sci 38 (1993) 769-788) for forensic sex assessment. They include caliper measurements of interarticular length, base and head width, base and head height, and maximum midshaft diameter. Over the last decade, a new set of measurements that encompass similar dimensions to those used by Scheuer and Elkington, but which are taken with a mini-osteometric board (MOB) have been developed by the lead author. Use of the MOB avoids the need to manipulate both the bone and calipers in three-dimensional space and causes less strain on the hands. However, the question of intra- and interobserver accuracy has not been adequately addressed for either set of measurements. The purpose of this study was to test both the Scheuer/Elkington and MOB measurements on 20 hands from 10 anatomical skeletons for intra- and inter-observer accuracy. The study found that 92% of the MOB measures had a lower intraobserver error, and 88% had a lower interobserver error than did the caliper measurements. It also found that the maximum midshaft diameter measurement used by Scheuer and Elkington is more repeatable than a mediolateral diameter. Overall, 88% of the 25 MOB measurements had median intraobserver error rates of under 1.5%, compared with 60% of the caliper measurements. Furthermore, the MOB measurements as a set were taken 10 to 12% faster than the caliper measurements.

Summary Parameter adjustment of the transmitted light source yields a good-quality image for video measurement microscopy. However, a disadvantage is that the measured size of the objects changes simultaneously while the parameters of the transmitted light source are adjusted, which directly affects the measurement accuracy adversely. Furthermore, the variation of the objects’ measured size leads to the magnification variation as well. In order to analyse how the measured size of the objects varies with the parameters, we apply a photometric method and an operator algebra method to derive a unified mathematical model that correlates the parameters of the transmitted light source with the measured size of the objects. Theoretical results show that factors including the illumination intensity, the diameter of the aperture stop and the field stop and the object thickness are important to the measured size of the objects. The simulation results have been verified thoroughly using a wide variety of internal and external diameter measurement experiments. The proposed method has proved to be suitable to determine how these parameters affect measured size of the objects.

BACKGROUND AND PURPOSE Diameter measurement of the third ventricle with magnetic resonance imaging (MRI) and recently also with transcranial sonography (TCS) has emerged as a surrogate marker for brain atrophy and disease progression in multiple sclerosis (MS). This study aims to evaluate TCS measurements of the third ventricle diameter in a clinical routine setting against MRI. METHODS Transverse diameters of the third ventricle were determined in 27 MS patients using both, TCS and MRI. In TCS, the distance between the leading edges of the brain-ventricle interfaces was assessed in axial image planes. In MRI, the transverse diameter of the mid-portion of the third ventricle was measured on axial T1-weighted images. RESULTS The mean diameter of the third ventricle was 4.0 mm (SD 1.7 mm), when measured with MRI, and 4.4 mm (SD 1.7 mm), when measured with TCS. The 95% limits of agreement of the Bland-Altman Plot were 2.93 mm (95% CI 2.08 to 3.78 mm) and −2.23 mm (95%CI −3.08 to −1.38 mm). Pearson correlation coefficient was .71 (P < .0001). CONCLUSIONS TCS may appear suitable as screening examination for the extent of brain atrophy at a single-point study, but at least in the early stages of the disease, TCS is not useful to monitor disease progression. J Neuroimaging 2010;20:53-57.

Background International Consensus Criteria (ICC) consider right-to-left shunt (RLS) present when Transcranial Doppler (TCD) detects even one microbubble (microB). Spencer Logarithmic Scale (SLS) offers more grades of RLS with detection of >30 microB corresponding to a large shunt. We compared the yield of ICC and SLS in detection and quantification of a large RLS. Subjects and methods We prospectively evaluated paradoxical embolism in consecutive patients with ischemic strokes or transient ischemic attack (TIA) using injections of 9 cc saline agitated with 1 cc of air. Results were classified according to ICC [negative (no microB), grade I (1-20 microB), grade II (>20 microB or "shower" appearance of microB), and grade III ("curtain" appearance of microB)] and SLS criteria [negative (no microB), grade I (1-10 microB), grade II (11-30 microB), grade III (31100 microB), grade IV (101300 microB), grade V (>300 microB)]. The RLS size was defined as large (>4 mm) using diameter measurement of the septal defects on transesophageal echocardiography (TEE). Results TCD comparison to TEE showed 24 true positive, 48 true negative, 4 false positive, and 2 false negative cases (sensitivity 92.3%, specificity 92.3%, positive predictive value (PPV) 85.7%, negative predictive value (NPV) 96%, and accuracy 92.3%) for any RLS presence. Both ICC and SLS were 100% sensitive for detection of large RLS. ICC and SLS criteria yielded a false positive rate of 24.4% and 7.7%, respectively when compared to TEE. Conclusions Although both grading scales provide agreement as to any shunt presence, using the Spencer Scale grade III or higher can decrease by one-half the number of false positive TCD diagnoses to predict large RLS on TEE.

A recent increase in published studies of lianas has been paralleled by a proliferation of protocols for censusing lianas. This article seeks to increase uniformity in liana inventories by providing specific recommendations for the determination of which taxa to include, the location of diameter measurement points on individual stems, the setting of minimum stem diameter cutoffs, the treatment of multiple-stemmed and rooted clonal groups, and the measurement of noncylindrical stems. Use of more uniform liana censusing protocols may facilitate comparison of independently collected data sets and further our understanding of global patterns in liana abundance, diversity, biomass, and dynamics.

Purpose To evaluate the reproducibility and safety of capsulorhexis femtosecond laser assisted. Methods Admitted patients for cataract surgery have been received into the “PERCY Military Hospital” refractive surgery unity.We have treated 11 eyes of 11 patients, on the Victus femtosecond laser platform.A control group (11 eyes of 11 patients) has been operated manually in the same center.The rhexis diameter measurement has been realized at one week postoperative,to the angiograph,as iris angiography,using the HRA OCT Spectralis.On the pictures,we measured the vertical diameter and the horizontal diameter.For the rhexis centration,three circles were drawn following the contour of the rhexis, the pupillary border,and the margin of limbus.We measured the position of rhexis center to pupillary center. Results In the laser assisted group,the mean horizontal rhexis diameter was 5.35 mm +/- 0.22,and the mean vertical rhexis diameter was 5.37 mm +/- 0.22. In the control group,the mean horizontal and vertical rhexis diameters were respectively 5.3 +/- 0.28,and 5.6 +/- 0.21.We found that 85% of femtosecond laser assisted rhexis were within 0.35 mm from the programmed diameter. In the control group,only 15% have obtained the same level of accuracy.In the laser group,the three circles have the same center,and then are concentric,tell-tale of a rhexis good centration,unlike the manual rhexis.The femtosecond laser rhexis was circular,regular and covers the IOL’s periphery including the haptics. Conclusion The femtosecond laser has multiple benefits for cataract surgery, as the regular and circular capsule, the reduced variability in the effective lens position. The technique is reproducible and very safe.

Purpose: An overview of the ultrasound imaging artifacts encountered in Mammosite balloon APBI is presented. The goal was to determine whether clinically relevant changes in balloon size resulting from leakage can be detected by ultrasound imaging and also to compare the magnitude of size variations using both ultrasound and CT imaging. Methods: Ultrasound imaging of a Mammosite balloon phantom was performed to better understand measurement errors and accuracy. The dose to the prescription point as a function of balloon diameter was computed for different sized balloons. The results were compared to phantom measurements of balloon diameter versus filling volume to assess the dose change that would result from tissue moving inward with a shrinking balloon boundary. In APBI patients undergoing a course of 10 treatment fractions, an assessment was made of the variability and accuracy of balloon size measured with ultrasound imaging compared to CT. Results: Ultrasound artifacts combine to form a false image of the distal balloon boundary. Proper US probe orientation and choice of measurement point locations improves distance measurement accuracy. A 1 mm change in balloon diameter is measurable with ±0.1 mm error; this 1 mm change corresponding to

Purpose: To investigate the effect on vessel sizing of varying the threshold in 3D volume‐rendered CTimages and to verify the results with a 2D computer simulation.Method and Materials: 3D‐rendered images of a phantom with a vessel of varying diameter and of a patient with a basilar tip aneurysm were displayed on a Vitrea 2 workstation. Vessel diameters measured from the images were plotted as a function of gray‐scale threshold and actual vessel diameters measured directly from the phantom. A MatLab program was used to simulate different‐size vessel image models by convolving a rect function with a Gaussian point spread function (PSF) and to investigate the effect of threshold on sizing these vessels. Results: Plots of measured vessel diameter vs. threshold setting for varying real‐vessel diameter exhibit a monotonic decrease; with the slope decreasing both for low thresholds because of the extended tail of the PSF and for high thresholds where the vessel rapidly shrinks and then disappears as the threshold exceeds the vessel gray level. For intermediate thresholds there is a greater rate of fall‐off for smaller vessels below the width of the system PSF. Plots of measured diameter vs. real diameter intersect the 45 degree identity line at increasing diameters for increasing intermediate threshold. The crossing‐point indicates the point where the measured diameter equals the real diameter for the given threshold. Below the crossing point, these curves demonstrate reduced measured diameter for smaller vessels and, above the crossing‐point, larger values for larger vessels. The simplified 2D vessel‐model simulation and workstation data follow similar trends. Conclusion: A threshold set to accurately measure one rendered‐vessel diameter will inaccurately render vessels of other diameters. Using this threshold, smaller vessels will be inaccurately small or not be visualized and larger vessels will be too large. (Support: NIH R01‐NS43924, R01‐EB002873, Toshiba Corp.).

Objectives: The cerebellum develops over a long period of time, making it vulnerable to a wide range of disorders such as Dandy-Walker malformation and variant. The advent of three dimensional ultrasonography is an extraordinary advance in fetal medicine diagnosis. The 3DXI is technique of comparing several slices displayed on the same screen, allows a slice-by-slice approach in ascertaining the most accurate measurement to be compared with the 2D. Our objective is to make a comparative evaluation of the transverse cerebellar diameter measurement by 2D ultrasonography (Fig. 1) and 3DXI, multi-slice view in 18–24 weeks fetuses. Methods: This transversal study included 69 healthy fetuses, between 18–24 weeks. The transverse cerebellar diameter was first measured by the conventional bi-dimensional sonography technique, then by 3DXI multi-slice view, using the Medison SonoAce X8 (Medison, Korea). The Wilcoxon signed-ranks test was used to compare the data. Results: The comparison of 69 measures of the cerebellum by 2D ultrasound and 3DXI shows an effective difference between the values obtained by 2D and 3D, indicating that the 3DXI values are larger than 2D (P < 0.01). Conclusions: Our results show that the 3D evaluation of the cerebellum seems to have a statistically significant measurement difference.