Van Gool Research Articles

An attempt to introduce dynamics into generalised exergy considerations

In previous research, the author developed a general abstract framework for the exergy content of a system of finite objects [Grubbström RW. Towards a generalized exergy concept. In: van Gool W, Bruggink JJC, editors. Energy and time in the economic and physical sciences. Amsterdam: North-Holland; 1985. p. 41–56]. Each such object is characterised by its initial extensive properties and has an inner energy written as a function of these properties. It was shown that if these objects were allowed to interact, there is a maximum amount of work that can be extracted from the system as a whole, and a general formula for this potential was provided. It was also shown that if one of the objects was allowed to be of infinite magnitude initially, taking on the role as an environment having constant intensive properties, then the formula provided took on the same form as the classical expression for exergy. As a side result, the theoretical considerations demonstrated that the second law of thermodynamics could be interpreted as the inner energy function being a (weakly) convex function of its arguments, when these are chosen as the extensive properties. Since exergy considerations are based on the principle that total entropy is conserved when extracting work, these processes would take an infinite time to complete. In the current paper, instead, a differential-equation approach is introduced to describe the interaction in finite time between given finite objects of a system. Differences in intensive properties between the objects provide a force enabling an exchange of energy and matter. An example of such an interaction is heat conduction. The resulting considerations explain how the power extracted from the system will be limited by the processes being required to perform within finite-time constraints. Applying finite-time processes, in which entropy necessarily is generated, leads to formulating a theory for a maximal power output from the system. It is shown that such a theory is possible to develop, and the resulting equilibrium conditions are compared with to those of the exergetic equilibrium.

Editorial: Marr Prize and Honorable Mentions at ICCV 2005

In order to commemorate David Marr, IJCV continues in this issue the tradition to publish papers that were awarded the Marr Prize at the IEEE International Conference on Computer Vision (ICCV). Under the guidance of the program chairs of the 10th ICCV’05 held in Beijing, Bill Freeman (MIT), Luc Van Gool (U Leuven, ETH Zurich) and Subhasis Chaudhuri (IIT Bombay), four papers were selected in a process meeting the high and well-established standards of previous conferences:

Colophon, contents, preface

The present volume marks the completion of a large research project by the Geological Survey of Denmark and Greenland (GEUS), focused on the northern part of the Palaeoproterozoic Nagssugtoqidian orogen of central West Greenland, and carried out by a team of Danish and international participants. The project comprised geological mapping as well as structural, geochronological, geochemical and economic geological studies. This volume contains reports on both Archaean and Palaeoproterozoic geology as well as a study of neotectonic brittle structures. The field work was carried out in 2000-2003 in the region between Nordre Strømfjord and Jakobshavn Isfjord (see e.g. van Gool & Piazolo 2006, this volume, fig. 1). The project had two immediate purposes, namely to establish an overview of the mineral resource potential of supracrustal rocks in the region between 66° and 70°15'N, and produce four new geological sheets in the Survey's 1:100 000 map series.

Removal of a Large Odontoma by Sagittal Split Osteotomy

Odontomas are the most common odontogenic tumors and are usually incidental findings in radiographic examination.1 When the odontoma is small or average size, the acceptable treatment is enucleation. The problem arises with large odontomas, the removal of which involves sacrifice of large amounts of bone, potential of mandibular fracture and damage to the inferior alveolar nerve. To avoid these complications on removing large tumors in the mandible, the use of the sagittal split osteotomy (SSO) technique was introduced in 1979 by Rittersma and van Gool.

A Comparison of Affine Region Detectors

The paper gives a snapshot of the state of the art in affine covariant region detectors, and compares their performance on a set of test images under varying imaging conditions. Six types of detectors are included: detectors based on affine normalization around Harris (Mikolajczyk and Schmid, 2002; Schaffalitzky and Zisserman, 2002) and Hessian points (Mikolajczyk and Schmid, 2002), a detector of ‘maximally stable extremal regions', proposed by Matas et al. (2002); an edge-based region detector (Tuytelaars and Van Gool, 1999) and a detector based on intensity extrema (Tuytelaars and Van Gool, 2000), and a detector of ‘salient regions', proposed by Kadir, Zisserman and Brady (2004). The performance is measured against changes in viewpoint, scale, illumination, defocus and image compression.The objective of this paper is also to establish a reference test set of images and performance software, so that future detectors can be evaluated in the same framework.

A performance evaluation of local descriptors

In this paper, we compare the performance of descriptors computed for local interest regions, as, for example, extracted by the Harris-Affine detector. Many different descriptors have been proposed in the literature. It is unclear which descriptors are more appropriate and how their performance depends on the interest region detector. The descriptors should be distinctive and at the same time robust to changes in viewing conditions as well as to errors of the detector. Our evaluation uses as criterion recall with respect to precision and is carried out for different image transformations. We compare shape context, steerable filters, PCA-SIFT, differential invariants, spin images, SIFT, complex filters, moment invariants, and cross-correlation for different types of interest regions. We also propose an extension of the SIFT descriptor and show that it outperforms the original method. Furthermore, we observe that the ranking of the descriptors is mostly independent of the interest region detector and that the SIFT-based descriptors perform best. Moments and steerable filters show the best performance among the low dimensional descriptors.

TOLTERODINE TREATMENT FOR CHILDREN WITH SYMPTOMS OF URINARY URGE INCONTINENCE SUGGESTIVE OF DETRUSOR OVERACTIVITY: RESULTS FROM 2 RANDOMIZED, PLACEBO CONTROLLED TRIALS

We report the results of the first 2 large randomized controlled trials designed to evaluate the efficacy and safety of tolterodine extended release in children 5 to 10 years old with symptoms of urinary urge incontinence suggestive of detrusor overactivity. Two double-blind, placebo controlled trials were conducted sequentially. Children 5 to 10 years old with incontinence suggestive of detrusor overactivity (1 or more diurnal incontinence episodes per 24 hours) were randomized to tolterodine (2 mg daily) or placebo for 12 weeks. The primary end point was the change from baseline to week 12 in the number of incontinence episodes per week. Changes from baseline in the number of voids per 24 hours and volume of urine per void were also evaluated. Exploratory analyses were conducted to determine whether particular subsets of patients showed differential responses to treatment. A total of 224 and 487 children (mean age 8 years) were randomized to placebo and tolterodine, respectively. Differences in the number of incontinence episodes per week, voids per 24 hours, and volume of urine per void between tolterodine and placebo did not reach statistical significance. This finding may be explained by a high placebo response and under dosage of tolterodine among children with greater body weight. Tolterodine was well tolerated. Analysis of the primary efficacy outcome did not reveal a statistically significant effect of treatment. However, secondary analyses demonstrated that tolterodine was well tolerated among 5 to 10-year-old children with diurnal incontinence. Exploratory analyses also showed that children weighing 35 kg or less with detrusor overactivity characterized by incontinence and/or frequent voiding benefited most from tolterodine treatment, suggesting that a weight adjusted dosing regimen may be required for optimal response among older and heavier children.

Fanconi Anemia Complementation Group D2 (FANCD2) Functions Independently of BRCA2- and RAD51-associated Homologous Recombination in Response to DNA Damage

The BRCA2 breast cancer tumor suppressor is involved in the repair of double strand breaks and broken replication forks by homologous recombination through its interaction with DNA repair protein Rad51. Cells defective in BRCA2.FANCD1 are extremely sensitive to mitomycin C (MMC) similarly to cells deficient in any of the Fanconi anemia (FA) complementation group proteins (FANC). These observations suggest that the FA pathway and the BRCA2 and Rad51 repair pathway may be linked, although a functional connection between these pathways in DNA damage signaling remains to be determined. Here, we systematically investigated the interaction between these pathways. We show that in response to DNA damage, BRCA2-dependent Rad51 nuclear focus formation was normal in the absence of FANCD2 and that FANCD2 nuclear focus formation and mono-ubiquitination appeared normal in BRCA2-deficient cells. We report that the absence of BRCA2 substantially reduced homologous recombination repair of DNA breaks, whereas the absence of FANCD2 had little effect. Furthermore, we established that depletion of BRCA2 or Rad51 had a greater effect on cell survival in response to MMC than depletion of FANCD2 and that depletion of BRCA2 in FANCD2 mutant cells further sensitized these cells to MMC. Our results suggest that FANCD2 mediates double strand DNA break repair independently of Rad51-associated homologous recombination.

Face processing in humans is compatible with a simple shape–based model of vision

Understanding how the human visual system recognizes objects is one of the key challenges in neuroscience. Inspired by a large body of physiological evidence, a general class of recognition models has emerged, which is based on a hierarchical organization of visual processing, with succeeding stages being sensitive to image features of increasing complexity. However, these models appear to be incompatible with some well-known psychophysical results. Prominent among these are experiments investigating recognition impairments caused by vertical inversion of images, especially those of faces. It has been reported that faces that differ 'featurally' are much easier to distinguish when inverted than those that differ 'configurally'; a finding that is difficult to reconcile with the physiological models. Here, we show that after controlling for subjects' expectations, there is no difference between 'featurally' and 'configurally' transformed faces in terms of inversion effect. This result reinforces the plausibility of simple hierarchical models of object representation and recognition in the cortex.

Low-pressure metamorphism during Archaean crustal growth: a low-strain zone in the northern Nagssugtoqidian orogen, West Greenland

One of the first detailed accounts of Precambrian supracrustal rocks in central West Greenland came from a small group of islands and skerries a few kilometres north-east of Aasiaat (Fig. 1). In 1948, K. Ellitsgaard-Rasmussen spent a few days on the islands and published a metamorphic study of their low-grade greenstones and aluminous clastic rocks (Ellitsgaard-Rasmussen 1954). He observed a striking dissimilarity between these supracrustal rocks and the grey gneisses found in most of the Aasiaat region, although the latter were at that time also assumed to be of supracrustal origin. He furthermore noted that the regional significance of the islands should be pursued, and that the island of Maniitsoq 4 km west of the small islands might hold a key to their interpretation. More than 50 years were to elapse before the islands were surveyed again in July 2003, during field work for the Ikamiut map sheet in the northern Nagssugtoqidian orogen (van Gool et al. 2002). The collision of two Archaean continents during the c. 1850 Ma Nagssugtoqidian orogeny caused intensive structural and thermal reworking at up to granulite facies grade in most of central West Greenland; see Connelly et al. (2000) and van Gool et al. (2002). The small islands north-east of Aasiaat are indeed regionally important, because they document a previously unrecognised low-grade, low-strain domain of presumed Archaean age that has largely escaped the Nagssugtoqidian orogeny, and as predicted by Ellitsgaard-Rasmussen (1954) a clue to their significance was found on Maniitsoq.

Effects of tumor-associated mutations on Rad54 functions.

Yeast RAD54 gene, a member of the RAD52 epistasis group, plays an important role in homologous recombination and DNA double strand break repair. Rad54 belongs to the Snf2/Swi2 protein family, and it possesses a robust DNA-dependent ATPase activity, uses free energy from ATP hydrolysis to supercoil DNA, and cooperates with the Rad51 recombinase in DNA joint formation. There are two RAD54-homologous genes in human cells, hRAD54 and RAD54B. Mutations in these human genes have been found in tumors. These tumor-associated mutations map to conserved regions of the hRad54 and hRad54B proteins. Here we introduced the equivalent mutations into the Saccharomyces cerevisiae RAD54 gene in an effort to examine the functional consequences of these gene changes. One mutant, rad54 G484R, showed sensitivity to DNA-damaging agents and reduced homologous recombination rates, indicating a loss of function. Even though the purified rad54 G484R mutant protein retained the ability to bind DNA and interact with Rad51, it was nearly devoid of ATPase activity and was similarly defective in DNA supercoiling and D-loop formation. Two other mutants, rad54 N616S and rad54 D442Y, were not sensitive to genotoxic agents and behaved like the wild type allele in homologous recombination assays. Consistent with the mild phenotype associated with the rad54 N616S allele, its encoded protein was similar to wild type Rad54 protein in biochemical attributes. Because dysfunctional homologous recombination gives rise to genome instability, our results are consistent with the premise that tumor-associated mutations in hRad54 and Rad54B could contribute to the tumor phenotype or enhance the genome instability seen in tumor cells.

Results of a questionnaire evaluating the effects of different methods of toilet training on achieving bladder control: E. Bakker, J.D. van Gool, M. van Sprundel et al. Br J Urol Internat 90:456–461, (September), 2002

Results of a questionnaire evaluating the effects of different methods of toilet training on achieving bladder control: E. Bakker, J.D. van Gool, M. van Sprundel et al. Br J Urol Internat 90:456–461, (September), 2002

A coastal survey in the southern part of the Palaeoproterozoic Rinkian fold belt, central West Greenland

A brief but potentially important part of the 2001 field investigations in the Precambrian of West Greenland (van Gool et al. 2002, this volume) was devoted to the southernmost part of the Palaeoproterozoic Rinkian fold belt east of Disko Bugt (Fig. 1). From 9–17 August the five authors carried out a reappraisal of critical Archaean and Proterozoic relationships and collected samples for precise geochronological studies. The principal aims are to date the main Rinkian tectonic and metamorphic events in this region as precisely as possible and compare them with the evolution of the Nagssugtoqidian orogen to the south (see van Gool et al. 2002, this volume, fig. 1). The vessel M/S Søkongen provided logistic support; a helicopter provided transport to Nunatarsuaq.

The mineral resource potential of the Nordre Strømfjord – Qasigiannguit region, southern and central West Greenland

Assessment of the mineral resource potential of the region between Sukkertoppen Iskappe and the southern part of Nuussuaq, West Greenland (66°N to 70°15´N; Fig. 1) is part of a regional resource assessment programme of the Geological Survey of Denmark and Greenland (GEUS) for 2000–2003. The year 2000 was dedicated to the compilation of existing data and the outlining of target areas for the field work in 2001 and 2002. This report gives a review of the work related to the gold and base metal potential in the Nordre Strømfjord – Qasigiannguit region, mainly based on results from the 2001 field work. Significant geological data have been collected from the region by the Survey, research groups and exploration companies during the past several decades; see Kalsbeek & Nutman (1996), Connelly & Mengel (2000) and van Gool et al. (2002, this volume) for geology, Steenfelt (2001) for geochemistry and Rasmussen & van Gool (2000) and Nielsen & Rasmussen (2002, this volume) for geophysics. Most of the region is easy of access, and exposures are excellent along the shores of the numerous fjords. However, inland areas may locally have extensive Quaternary cover.

Geological correlation of magnetic susceptibility and profiles from Nordre Strømfjord, southern West Greenland

The Palaeoproterozoic Nagssugtoqidian orogen is dominated by reworked Archaean gneisses with minor Palaeoproterozoic intrusive and supracrustal rocks. The Nagssugtoqidian orogen (Fig. 1) was the focus of regional geological investigations by the Geological Survey of Denmark and Greenland (GEUS) in 2001 (van Gool et al. 2002, this volume). In conjunction with this project, geophysical studies in the inner part of Nordre Strømfjord, Kuup Akua and Ussuit were undertaken as part of the Survey’s mineral resource assessment programme in central West Greenland. The studies include geophysical modelling of airborne magnetic data, follow-up studies of aeromagnetic anomalies by magnetic ground surveying, and geostatistical treatment and integration of different geological, geophysical and geochemical data. The aim is to obtain an interpretation of the region in terms of both regional geological features and modelling of local features of relevance for the mineral resource assessment. This paper presents an account of the field work and some of the new data.

Aeromagnetic survey in central West Greenland: project Aeromag 2001

The series of government-funded geophysical surveys in Greenland was continued during the spring and summer of 2001 with a regional aeromagnetic survey north of Uummannaq, project Aeromag 2001 (Fig. 1). The survey added about 70 000 line kilometres of high-quality magnetic measurements to the existing database of modern airborne geophysical data from Greenland. This database includes both regional high-resolution aeromagnetic surveys and detailed surveys with combined electromagnetic and magnetic airborne measurements.High-quality magnetic data are now available for all the ice-free area of West and South Greenland from the southern tip of Greenland to Upernavik Kujalleq/Søndre Upernavik (Fig. 1). The total surveyed area with highresolution magnetic data is 250 000 km2 and corresponds to a total of 515 000 line kilometres. Detailed surveys with combined electromagnetic and magnetic measurements were carried out in six separate surveys in selected areas of high mineral potential during project AEM Greenland 1994–1998, a total of 75 000 line kilometres. Descriptions of the previous surveys can be found in Thorning (1993), Stemp & Thorning (1995), Thorning & Stemp (1996, 1998), Stemp (1997), Rasmussen & Thorning (1999), Rasmussen & van Gool (2000) and Rasmussen et al. (2001).

BOOK REVIEWS

Book Reviwed in this article:PHOTOGRAMMETRIC WEEK ‘01. Edited by D. Fritsch and R. Spiller. WichmannPRACTICAL APPLICATIONS OF GIS FOR ARCHAEOLOGISTS: A PREDICTIVE MODELLING KIT. Edited by K. L. Westcott and R. J. Brandon.MANUAL OF GEOSPATIAL SCIENCE AND TECHNOLOGY. Edited by J. D. Bossler.WITH COMPASS AND CHAIN: EARLY AMERICAN SURVEYORS AND THEIR NSTRUMENTS. By S. A. Bedini.NEGLIGENCE IN VALUATIONS AND SURVEYS. By J. Murdoch.GEOGRAPHIC DATA MINING AND KNOWLEDGE DISCOVERY. Edited by H. J. Miller and J. Han.AUTOMATIC GENERALISATION PROJECT: LEARNING PROCESS FROM INTERACTIVE GENERALISATION. Report bu A. Ruas.REMOTE SENSING AND URBAN ANALYSIS. GISDATA 9. By J. ‐P. Donnay. M. J. Barnsley and P. A. Longley.VIRTUAL REALITY IN GEOGRAPHY. Edited by P. Fisher and D. Unwin.CLASSIFICATION METHODS FOR REMOTELY SENSED DATA. By B. Tso and P. M. Mather.AUTOMATIC EXTRACTION OF MAN‐MADE OBJECTS FROM AERIAL AND SPACE IMAGES (III). Edited by E. P. Gruen and L. van Gool.CALIBRATION AND ORIENTATION OF CAMERAS IN COMPUTER VISION. Edited by A. Gruen and T. S. Huang.WORKSHOP ON AIRBORNE LASERSCANNING AND INTERFEROMETRIC SAR FOR DETAILED DIGITAL ELEVATION MODELS. Edited by K. TorilegÅrd and J. Nelson.GEOGRAPHIC INFORMATION SYSTEMS FOR GROUP DECISION MAKING. By P. Jankowski and T. Nyerges.MODELLING SCALE IN GEOGRAPHICAL INFORMATION SCIENCE. Edited by N. J. Tale and P. M. Atkinson.DIGITAL PHOTOGRAMMETRY. Edited by M. Kasser and Y. Egels.

It’s Renin in the Brain

Since the first description of renin, angiotensinogen and angiotensin as well as converting enzyme and angiotensin receptors in the brain exactly 30 years ago,1–5⇓⇓⇓⇓ there was a heated debate, whether an endogenous intrinsic brain renin- angiotensin system (RAS) exists or not.6,7⇓ For a long time, the “believers” of local angiotensin II generation by the brain RAS were in a minority. Even at a symposium 1981, celebrating the 10-year anniversary of the discovery of the brain RAS, there was skepticism and the question whether the “renin-like” enzyme in brain was identical with cathepsins, tonin, or other proteases was a matter of debate. Historically, it is interesting that the presence in the brain of other classically peripheral peptides such as insulin, glucagon, and substance P was accepted without identification of the local synthetic pathway and less controversial than angiotensin as neuropeptide. Open letters, public debates, and personal accusations nourished sometimes emotional controversy whether angiotensin could be generated locally in tissue. The brain was a model for angiotensin generating pathways in other extrarenal tissues because the blood-brain barrier, which is impermeable for proteins and peptides, made it more unlikely that the RAS components measured in the brain were contaminations from the plasma. Angiotensin has extremely powerful effects on the brain that synergistically increase blood volume and blood pressure, eg, by stimulation of water intake and salt appetite, release of various pituitary hormones, increase of sympathetic tone, and decrease of baroreceptor reflex.7 The local generation of angiotensin II in the brain by an endogenous intrinsic RAS could therefore be extremely important for cardiovascular control and beyond. With the advent of transgenic technology, novel approaches to study the mechanistic and functional aspects of the brain RAS became available. Renin and angiotensinogen could be overexpressed or ablated …

THE TREATMENT OF POST-URETHROTOMY INCONTINENCE IN PEDIATRIC AND ADOLESCENT FEMALES

No AccessJournal of UrologyPEDIATRIC UROLOGY1 Mar 2001THE TREATMENT OF POST-URETHROTOMY INCONTINENCE IN PEDIATRIC AND ADOLESCENT FEMALES TOM P. V.M. de JONG, JAN D. VAN GOOL, PIETER DIK, AART J. KLIJN, and MARIANNE A.W. VIJVERBERG TOM P. V.M. de JONGTOM P. V.M. de JONG More articles by this author , JAN D. VAN GOOLJAN D. VAN GOOL More articles by this author , PIETER DIKPIETER DIK More articles by this author , AART J. KLIJNAART J. KLIJN More articles by this author , and MARIANNE A.W. VIJVERBERGMARIANNE A.W. VIJVERBERG More articles by this author View All Author Informationhttps://doi.org/10.1016/S0022-5347(05)66577-9AboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract Purpose: Until 1986 many urologists performed currently outdated, redundant internal urethrotomy as standard therapy for recurrent urinary tract infection in girls. We describe the results of therapy in patients who became incontinent due to previous internal urethrotomy. Materials and Methods: Between 1986 and 1995, 21 female patients with post-Otis urethrotomy incontinence have presented at our department with combined dysfunctional voiding, recurrent urinary tract infection and various types of urinary incontinence partially based on bladder instability and often provoked by abdominal straining. All cases were diagnosed by repeat video urodynamics and ultrasound of the open bladder neck. Endoscopy provided proof of scarring in the bladder neck and urethra. All patients except 1 underwent conservative treatment for at least 2 years, consisting of pharmacological therapy, physical therapy and biofeedback training. Surgical therapy to cure incontinence was performed in 14 cases, including a conventional Burch-type colposuspension in 5, modified needle colposuspension in 4 and complete endoscopic excision of the urethral scars followed by open reconstruction of the bladder neck and urethra in an abdominoperineal procedure in 5. Results: Conservative treatment has been completely successful in 7 patients. Primary open or needle colposuspension was unsuccessful in 6 of 9 cases, including several requiring further surgery to achieve dryness. The results of excising urethral scars with bladder neck and urethral reconstruction were good in 4 of 5 patients at a followup of at least 4 years. Conclusions: When previous internal urethrotomy appears to be an important factor in the evaluation of incontinence, conservative therapy is the treatment of choice. Conservative therapy should consist of biofeedback reeducation of the voiding pattern and physical therapy. When surgery is needed, excision of the urethral scars with reconstruction of the bladder neck and urethra plus colposuspension is superior to colposuspension only. References 1 : Internal urethrotomy and recurrent urinary tract infection in female children. I. Results in the management of infection. J Urol1968; 100: 297. Link, Google Scholar 2 : Bladder neck obstruction in children. J Urol1963; 89: 384. Link, Google Scholar 3 : A blind comparison of dilatation, urethrotomy and medication alone in the treatment of urinary tract infection in girls. J Urol1973; 109: 917. Link, Google Scholar 4 : Internal urethrotomy in girls and its impact on the urethral intrinsic and extrinsic continence mechanisms. J Urol1986; 136: 1248. Link, Google Scholar 5 : Internal urethrotomy in female subjects. J Urol1986; 136: 1280. Link, Google Scholar 6 : Bladder neck reconstruction for total urinary incontinence: 10 years experience. J Urol1981; 125: 321. Link, Google Scholar 7 : Construction of female urethra from vaginal wall and a perineal flap. J Urol1980; 123: 657. Google Scholar 8 : Bladder rehabilitation: the effect of a cognitive training program on urge incontinence. Eur Urol1997; 31: 68. Google Scholar 9 : Outpatient pelvic floor therapy in girls with daytime incontinence and dysfunctional voiding. Urology1996; 48: 923. Google Scholar 10 : Standardisation and definitions in lower urinary tract dysfunction in children. Br J Urol1998; 81: 1. Google Scholar From the Pediatric Renal Center, University Children’s Hospital, University Medical Center Utrecht, Utrecht, The Netherlands© 2001 by American Urological Association, Inc.FiguresReferencesRelatedDetails Volume 165Issue 3March 2001Page: 929-933 Advertisement Copyright & Permissions© 2001 by American Urological Association, Inc.Keywordsurinary incontinenceurethracicatrixurinary tract infectionsiatrogenic diseaseMetricsAuthor Information TOM P. V.M. de JONG More articles by this author JAN D. VAN GOOL More articles by this author PIETER DIK More articles by this author AART J. KLIJN More articles by this author MARIANNE A.W. VIJVERBERG More articles by this author Expand All Advertisement PDF downloadLoading ...

Urethral syndromes in children.

1. Walid Farhat, MD* 2. Gordon McLorie, MD* 1. 2. *Division of Urology, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada. Objectives After completing this article, readers should be able to: 1. Describe the evaluation of a child suspected of having urethritis. 2. Delineate the screening tests that have the highest yield for urethritis in young children. 3. List components of a behavioral modification approach to treating dysfunctional voiding. 4. Compare and contrast physical findings in gonococcal and nongonococcal urethritis. Inflammation of the urethra (urethritis) may be due to infection, trauma, allergy, foreign body, or an undetermined factor. Certain characteristics distinguish urethritis in the pediatric population from that in adults. First, urethritis in adults and adolescents has an infectious etiology and always is the result of sexual contact; infectious urethritis in the pediatric age group is uncommon, except in sexually active adolescents or children who have been sexually abused by an adult who has the disease. Second, the variability and nonspecificity of a variety of noninfectious urethral pathologies may mimic infectious urethritis in children. Children who have urethritis may present with irritative voiding symptoms, such as dysuria, urgency, or frequency; possible urethral discharge; initial hematuria; or blood spotting on the underwear. Patients suspected of having urethritis are evaluated with a detailed history, physical examination, urethral smear, or urine culture. In girls, examination may show evidence of vaginitis, which is a common cause of dysuria after urinary tract infection, labial adhesions, or even sexual abuse; in males, results of the examination frequently are inconclusive. In infants, young children, and sexually inactive adolescents, screening tests that have the highest yield include urinalysis and abdominal ultrasonography (US); uroflow is reserved for toilet-trained children. The urine should be examined for evidence of infection or hematuria. Abdominal US can diagnose a variety of abnormalities, including bladder stone or inflammation, ureterocele, foreign body, or tumor. Uroflow is a noninvasive urodynamics test that assesses the ability to initiate voiding on command, quantitates …