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Discovery of structure-property relationships in thin film alloys of complex metal oxides enabled by high-throughput materials synthesis and characterization facilities is demonstrated here with a case-study. Thin films of binary transition metal oxides (Ti-Zn) are prepared by pulsed laser deposition with continuously varying Ti:Zn ratio, creating combinatorial samples for exploration of the properties of this material family. The atomic structure and electronic properties are probed by spatially resolved techniques including x-ray absorption near edge structures (XANES) and x-ray fluorescence (XRF) at the Ti and Zn K-edge, x-ray diffraction, and spectroscopic ellipsometry. The observed properties as a function of Ti:Zn ratio are resolved into mixtures of five distinguishable phases by deploying multivariate curve resolution analysis on the XANES spectral series, under constraints set by results from the other characterization techniques. First-principles computations based on density function theory connect the observed properties of each distinct phase with structural and spectral characteristics of crystalline polymorphs of Ti-Zn oxide. Continuous tuning of the optical absorption edge as a function of Ti:Zn ratio, including the unusual observation of negative optical bowing, exemplifies a functional property of the film correlated to the phase evolution., (© 2023 IOP Publishing Ltd.)

To examine ion solvation, exchange, and speciation for minority components in molten salts (MS) typically found as corrosion products, we propose a multimodal approach combining extended X-ray absorption fine structure (EXAFS) spectroscopy, optical spectroscopy, ab initio molecular dynamics (AIMD) simulations, and rate theory of ion exchange. Going beyond conventional EXAFS analysis, our method can accurately quantify populations of different coordination states of ions with highly disordered coordination environments via linear combination fitting of the EXAFS spectra of these coordination states computed from AIMD to the experimental EXAFS spectrum. In a case study of dilute Ni(II) dissolved in the ZnCl 2 +KCl melts, our method reveals heterogeneous distributions of coordination states of Ni(II) that are sensitive to variations in temperature and melt composition. These results are fully explained by the difference in the chloride exchange dynamics at varied temperatures and melt compositions. This insight will enable a better understanding and control of ion solubility and transport in MS.

A line defect with metallic characteristics has been found in optically transparent BaSnO 3 perovskite thin films. The distinct atomic structure of the defect core, composed of Sn and O atoms, was visualized by atomic-resolution scanning transmission electron microscopy (STEM). When doped with La, dopants that replace Ba atoms preferentially segregate to specific crystallographic sites adjacent to the line defect. The electronic structure of the line defect probed in STEM with electron energy-loss spectroscopy was supported by ab initio theory, which indicates the presence of Fermi level-crossing electronic bands that originate from defect core atoms. These metallic line defects also act as electron sinks attracting additional negative charges in these wide-bandgap BaSnO 3 films., (Copyright © 2021 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).)

Molten salts are of great interest as alternative solvents, electrolytes, and heat transfer fluids in many emerging technologies. The macroscopic properties of molten salts are ultimately controlled by their structure and ion dynamics at the microscopic level and it is therefore vital to develop an understanding of these at the atomistic scale. Herein, we present high-energy X-ray scattering experiments combined with classical and ab initio molecular dynamics simulations to elucidate structural and dynamical correlations across the family of alkali-chlorides. Computed structure functions and transport properties are in reasonably good agreement with experiments providing confidence in our analysis of microscopic properties based on simulations. For these systems, we also survey different rate theory models of anion exchange dynamics in order to gain a more sophisticated understanding of the short-time correlations that are likely to influence transport properties such as conductivity. The anion exchange process occurs on the picoseconds time scale at 1100 K and the rate increases in the order KCl < NaCl < LiCl, which is in stark contrast to the ion pair dissociation trend in aqueous solutions. Consistent with the trend we observe for conductivity, the cationic size/mass, as well as other factors specific to each type of rate theory, appear to play important roles in the anion exchange rate trend.

Simulations of excited state properties, such as spectral functions, are often computationally expensive and therefore not suitable for high-throughput modeling. As a proof of principle, we demonstrate that graph-based neural networks can be used to predict the x-ray absorption near-edge structure spectra of molecules to quantitative accuracy. Specifically, the predicted spectra reproduce nearly all prominent peaks, with 90% of the predicted peak locations within 1 eV of the ground truth. Besides its own utility in spectral analysis and structure inference, our method can be combined with structure search algorithms to enable high-throughput spectrum sampling of the vast material configuration space, which opens up new pathways to material design and discovery.

Fast-charging batteries typically use electrodes capable of accommodating lithium continuously by means of solid-solution transformation because they have few kinetic barriers apart from ionic diffusion. One exception is lithium titanate (Li 4 Ti 5 O 12 ), an anode exhibiting extraordinary rate capability apparently inconsistent with its two-phase reaction and slow Li diffusion in both phases. Through real-time tracking of Li + migration using operando electron energy-loss spectroscopy, we reveal that facile transport in Li 4+ x Ti 5 O 12 is enabled by kinetic pathways comprising distorted Li polyhedra in metastable intermediates along two-phase boundaries. Our work demonstrates that high-rate capability may be enabled by accessing the energy landscape above the ground state, which may have fundamentally different kinetic mechanisms from the ground-state macroscopic phases. This insight should present new opportunities in searching for high-rate electrode materials., (Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)

Understanding the factors that control solubility and speciation of metal ions in molten salts is key for their successful use in molten salt reactors and electrorefining. Here, we employ X-ray and optical absorption spectroscopies and molecular dynamics simulations to investigate the coordination environment of Ni(II) in molten ZnCl 2 , where it is poorly soluble, and contrast it with highly soluble Co(II) over a wide temperature range. In solid NiCl 2 , the Ni ion is octahedrally coordinated, whereas the ZnCl 2 host matrix favors tetrahedral coordination. Our experimental and computational results show that the coordination environment of Ni(II) in ZnCl 2 is disordered among tetra- and pentacoordinate states. In contrast, the local structure of dissolved Co(II) is tetrahedral and commensurate with the ZnCl 2 host's structure. The heterogeneity and concomitant large bond length disorder in the Ni case constitute a plausible explanation for its lower solubility in molten ZnCl 2 .

The development of technologies for nuclear reactors based on molten salts has seen a big resurgence. The success of thermodynamic models for these hinges in part on our ability to predict at the atomistic level the behavior of pure salts and their mixtures under a range of conditions. In this letter, we present high-energy X-ray scattering experiments and molecular dynamics simulations that describe the molten structure of mixtures of MgCl 2 and KCl. As one would expect, KCl is a prototypical salt in which structure is governed by simple charge alternation. In contrast, MgCl 2 and its mixtures with KCl display more complex correlations including intermediate-range order and the formation of Cl - -decorated Mg 2+ chains. A thorough computational analysis suggests that intermediate-range order beyond charge alternation may be traced to correlations between these chains. An analysis of the coordination structure for Mg 2+ ions paints a more complex picture than previously understood, with multiple accessible states of distinct geometries.

Backround: To evaluate the factors including pelvic dimensions, which might influence operative difficulty and complications after open radical cystoprostatectomy and orthotopic neobladder reconstruction in men., Methods: A total of 198 RC patients operated in our institution with preoperative magnetic resonance (MRI) were analyzed were included in the study. Pelvic dimensions, including interspinous distance (ISD), bony femoral - (BFW) and soft tissue width (SW), apical prostate depth (AD), upper conjugate (UC), lower conjugate (LC) were measured by preoperative MRI. BFW, ISD, and SW indexes were defined as BFW/AD, ISD/AD, and SW/AD, respectively. Complicatons were classified according to the Clavien-Dindo classification system. As indicators of surgical difficulty; transfusion rate (TR), estimated blood loss (EBL), operative time (OT) and hospital stay (HS) were assessed. SPSS version 17.0 was used for statistical analyses., Results: A total of 239 complications developed in 143 of the 198 patients (72.2%). Correlation analysis revealed a significant indirect relationship between TR and SW/AD (P=0.023). For EBL, there were significant indirect correlations between the SW/AD, BFW/AD and ISD/AD indexes (P=0.026, P=0.05, P=0.009; respectively). Additionally, OT was directly correlated body mass index (BMI) (P=0.001); and indirectly correlated with UC, SW/AD, and BFW/AD (P=0.047, P=0.038, P=0.016, respectively). On multivariate logistic regression analyses higher American Society of Anesthesiologist (ASA) score was associated with major complications. Multivariate analyses revealed that pathological stage was a significant predictor of EBL., Conclusions: Patients with smaller pelvises might undergo more difficult surgeries. However, it seems that small sized pelvis does not impact on operative difficulty and complication rate in radical cystoprostatectomy and orthotopic neobladder.

Due to its chemical stability, titania (TiO 2 ) thin films increasingly have significant impact when applied as passivation layers. However, optimization of growth conditions, key to achieving essential film quality and effectiveness, is challenging in the few-nanometers thickness regime. Furthermore, the atomic-scale structure of the nominally amorphous titania coating layers, particularly when applied to nanostructured supports, is difficult to probe. In this Letter, the quality of titania layers grown on ZnO nanowires is optimized using specific strategies for processing of the nanowire cores prior to titania coating. The best approach, low-pressure O 2 plasma treatment, results in significantly more-uniform titania films and a conformal coating. Characterization using X-ray absorption near edge structure (XANES) reveals the titania layer to be highly amorphous, with features in the Ti spectra significantly different from those observed for bulk TiO 2 polymorphs. Analysis based on first-principles calculations suggests that the titania shell contains a substantial fraction of under-coordinated Ti 4+ ions. The best match to the experimental XANES spectrum is achieved with a "glassy" TiO 2 model that contains ∼50% of under-coordinated Ti 4+ ions, in contrast to bulk crystalline TiO 2 that only contains 6-coordinated Ti 4+ ions in octahedral sites.

The valence-to-core (V2C) portion of x-ray emission spectroscopy (XES) measures the electron states close to the Fermi level. These states are involved in bonding, thus providing a measure of the chemistry of the material. In this article, we show the V2C XES spectra for several niobium compounds. The Kβ ″ peak in the V2C XES results from the transition of a ligand 2 s electron into the 1 s core-hole of the niobium, a transition allowed by hybridization with the niobium 4 p . This location in energy of this weak peak shows a strong ligand dependence, thus providing a sensitive probe of the ligand environment about the niobium.

Doped metal oxide materials are commonly used for applications in energy storage and conversion, such as batteries and solid oxide fuel cells. The knowledge of the electronic properties of dopants and their local environment is essential for understanding the effects of doping on the electrochemical properties. Using a combination of X-ray absorption near-edge structure spectroscopy (XANES) experiment and theoretical modeling we demonstrate that in the dilute (1 at. %) Mn-doped lithium titanate (Li 4/3 Ti 5/3 O 4 , or LTO) the dopant Mn 2+ ions reside on tetrahedral (8 a ) sites. First-principles Mn K-edge XANES calculations revealed the spectral signature of the tetrahedrally coordinated Mn as a sharp peak in the middle of the absorption edge rise, caused by the 1 s → 4 p transition, and it is important to include the effective electron-core hole Coulomb interaction in order to calculate the intenisty of this peak accurately. This dopant location explains the impedance of Li migration through the LTO lattice during the charge-discharge process, and, as a result - the observed remarkable 20% decrease in electrochemical rate performance of the 1% Mn-doped LTO compared to the pristine LTO.

Zero-strain electrodes, such as spinel lithium titanate (Li 4/3 Ti 5/3 O 4 ), are appealing for application in batteries due to their negligible volume change and extraordinary stability upon repeated charge/discharge cycles. On the other hand, this same property makes it challenging to probe their structural changes during the electrochemical reaction. Herein, we report in situ studies of lithiation-driven structural transformations in Li 4/3 Ti 5/3 O 4 via a combination of X-ray absorption spectroscopy and ab initio calculations. Based on excellent agreement between computational and experimental spectra of Ti K-edge, we identified key spectral features as fingerprints for quantitative assessment of structural evolution at different length scales. Results from this study indicate that, despite the small variation in the crystal lattice during lithiation, pronounced structural transformations occur in Li 4/3 Ti 5/3 O 4 , both locally and globally, giving rise to a multi-stage kinetic process involving mixed quasi-solid solution/macroscopic two-phase transformations over a wide range of Li concentrations. This work highlights the unique capability of combining in situ core-level spectroscopy and first-principles calculations for probing Li-ion intercalation in zero-strain electrodes, which is crucial to designing high-performance electrode materials for long-life batteries.

Perovskite oxides form an eclectic class of materials owing to their structural flexibility in accommodating cations of different sizes and valences. They host well-known point and planar defects, but so far no line defect has been identified other than dislocations. Using analytical scanning transmission electron microscopy (STEM) and ab initio calculations, we have detected and characterized the atomic and electronic structures of a novel line defect in NdTiO 3 perovskite. It appears in STEM images as a perovskite cell rotated by 45°. It consists of self-organized Ti-O vacancy lines replaced by Nd columns surrounding a central Ti-O octahedral chain containing Ti 4+ ions, as opposed to Ti 3+ in the host. The distinct Ti valence in this line defect introduces the possibility of engineering exotic conducting properties in a single preferred direction and tailoring novel desirable functionalities in this Mott insulator.

A giant bandgap reduction in layered GaTe is demonstrated. Chemisorption of oxygen to the Te-terminated surfaces produces significant restructuring of the conduction band resulting in a bandgap below 0.8 eV, compared to 1.65 eV for pristine GaTe. Localized partial recovery of the pristine gap is achieved by thermal annealing, demonstrating that reversible band engineering in layered semiconductors is accessible through their surfaces., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Background: Autologous serum skin test (ASST) is an in vivo test to demonstrate circulating endogenous proinflammatory or wheal-inducing factors in urticaria patients. While ASST was negative in a patient with solar urticaria and in a patient with localized heat urticaria, test results turned to positive when performed with visible light-irradiated and heated serums, respectively. These data suggest that some factors and/or antibodies in serum may be activated or inhibited with different factors. We aimed to investigate whether or not ASST results change when performed with narrowband ultraviolet B (UVB)-irradiated serum., Materials and Methods: Seventy-seven patients with chronic idiopathic urticaria underwent ASST twice in consecutive days. The second ASST was performed with narrowband UVB-irradiated serum. The results of the first and second ASSTs were compared., Results: The first ASST results were positive in 46 (59.7%) patients. ASST results reversed oppositely in 36 (46.8%) patients, turned from negative to positive in 19 patients, and turned from positive to negative in 17 patients when performed with narrowband UVB-irradiated serum., Conclusion:  Our results suggest that narrowband UVB may have modifying effects on some wheal-inducing factors and/or antibodies. On which factors in serum narrowband UVB has effects may be investigated., (© 2013 The International Society of Dermatology.)

We determine the frictional figures of merit for a pair of layered honeycomb nanostructures, such as graphane, fluorographene, MoS2 and WO2 moving over each other, by carrying out ab initio calculations of interlayer interaction under constant loading force. Using the Prandtl-Tomlinson model we derive the critical stiffness required to avoid stick-slip behavior. We show that these layered structures have low critical stiffness even under high loading forces due to their charged surfaces repelling each other. The intrinsic stiffness of these materials exceeds critical stiffness and thereby the materials avoid the stick-slip regime and attain nearly dissipationless continuous sliding. Remarkably, tungsten dioxide displays a much better performance relative to others and heralds a potential superlubricant. The absence of mechanical instabilities leading to conservative lateral forces is also confirmed directly by the simulations of sliding layers.

Choriocarcinoma is the most malignant tumor of gestational trophoblastic neoplasia. It grows rapidly and metastasizes to the lung, liver, and less frequently, the brain. Metastases to the kidney are rare in the literature, and bilateral involvement is even more scarce. Renal involvement of choriocarcinoma is highly exceptional and may mimic renal cell carcinoma. Here we report a case of bilateral renal choriocarcinoma presenting 5 years after a history of a total anterior hysterectomy because of a hydatidiform mole.

Purpose: To evaluate the effect of the number of dissected lymph nodes (LNs) during radical cystectomy on survival outcomes., Materials and Methods: Medical files of 211 patients who underwent cystectomy between 1996 and 2009 were retrospectively evaluated. Seventy-four patients were included in the study and divided into two groups regarding the median number of retrieved LNs (median number = 13); 36 patients in the 1st and 38 in the 2nd group. Radical cystectomy, urinary diversion, and pelvic LN dissection were done in all the patients. When necessary, adjuvant chemotherapy was applied. Kaplan-Meier survival analysis was performed to compare survival outcomes of the groups., Results: Of 74 patients, 67 (90.5%) were men and 7 (9.5%) were women, with the mean age of 61.7 years (range, 39 to 83 years). Age distribution, pathologic stages, carcinoma in situ occurrence, adjuvant chemotherapy rates, LN involvement, and median follow-up period were similar in both groups. Mean dissected LNs number in the 1st and 2nd groups was 6.17 (range, 1 to 12) and 21.6 (range, 13 to 41), respectively. Five-year estimated overall survival rates were 24.5% and 60.5% (P = .002) while five-year estimated disease-specific survival rates were 43.7% and 74.4% (P = .049), respectively., Conclusion: Although exact guidelines are not described, it seems that dissection of high number of LNs during radical cystectomy is crucial.

Dorsal vein rupture of the penis is a rare condition, and few cases have been reported in the literature. Herein we report a 41-year-old man who presented with mildly painful and acute swollen penis, which initially imitated a penile fracture but was surgically explored and shown to be a superficial dorsal vein rupture.

Aggressive fibromatosis or desmoid tumor, is a histologically benign entity with unknown etiology that may present a serious clinical course. Due to its high tendency to recur and local aggressive behavior and as there is no established effective medical treatment, complete surgical excision remains the sole management. To our knowledge, we describe the first case of giant desmoid tumor which arised from ileal neobladder mesenterium in a bladder cancer patient with orthotopic substitution.

First-principles calculations of structure optimization, phonon modes, and finite temperature molecular dynamics predict that silicon and germanium can have stable, two-dimensional, low-buckled, honeycomb structures. Similar to graphene, these puckered structures are ambipolar and their charge carriers can behave like a massless Dirac fermion due to their pi and pi(*) bands which are crossed linearly at the Fermi level. In addition to these fundamental properties, bare and hydrogen passivated nanoribbons of Si and Ge show remarkable electronic and magnetic properties, which are size and orientation dependent. These properties offer interesting alternatives for the engineering of diverse nanodevices.

Introduction: The aim of this study is to compare two different anesthetic techniques in radical cystectomy with regard to blood loss, transfusional requirements, intraoperative complications and the quality of analgesia., Materials and Methods: 50 patients scheduled for radical cystectomy were randomized to two groups: group GA - general anesthesia, n = 25 and group CEGA - combined epidural and general anesthesia. The patients were monitored and hemodynamic changes, intraoperative bleeding, transfusional requirements, quality of analgesia and postoperative complications were evaluated., Results: There were no significant differences between the demographic characteristics of the two groups. Intraoperative bleeding which was 874.8 +/- 190.7 ml in the CEGA group and 1,248.3 +/- 343.4 ml in the GA group was statistically different (p < 0.05). Significantly more intraoperative blood transfusions in terms of units were required in the GA group. Analgesia was better in the CEGA group, with VAS values at 0, 1, 2, 4, 6, 12 and 24 h significantly (p < 0.05) lower than those observed in the GA group. No significant differences in intraoperative hemodynamic parameters or postoperative complications were noted between the two groups., Conclusions: Statistically significant differences in intraoperative bleeding were observed between the two groups: CEGA provides lower intraoperative bleeding and a better postoperative analgesia. Major operations such as radical cystectomy, which also is associated with considerable blood loss, a combination of general and epidural anesthesia may allow for less blood loss, with a better postoperative analgesia and without any increase in complications.

Purpose: We investigated the effect of extracorporeal shockwave lithotripsy (SWL) on the serum prostate specific antigen (PSA) concentration., Patients and Methods: A total of 22 male patients with a mean age of 52.9 years (range 37-67 years) were treated with SWL for distal ureteral calculi close to the ureteral orifice. Serum samples were drawn for measurement of PSA values just before (PSA-1) and 45 minutes (PSA-2) and 7 days (PSA-3) after the session. None of the patients had urinary tract infection or any abnormal finding on digital rectal examination. The SWL sessions were performed with the Wolf piezoelectric 2300 lithotripter that has a therapeutic focus of 3 x 11 mm. The mean number of shockwaves per patient was 2204. Student's t-test was used for statistical analysis. At 1 year, all patients completed a questionnaire concerning recent diagnosis of prostate cancer., Results: The mean total PSA concentration before SWL was 3.13 ng/mL and rose to 3.91 ng/mL 45 minutes after the session. The mean PSA-3 value was 3.76 ng/mL. The mean free PSA values were 0.80, 0.83, and 0.77 ng/mL, respectively. The difference between PSA-1 and PSA-2 was statistically significant; all of the other differences were not significant. None of the patients reported prostate cancer at 1 year., Conclusion: Shockwave lithotripsy affects prostate epithelial cells and may cause a minor rise in total serum PSA values. However, this rise does seem to impair the value of PSA in patients with undiagnosed prostate cancer.

The aim of this study was to evaluate the etiology of erectile dysfunction (ED) in patients under the age of 40 years. Eighty one patients were included in this study. All patients underwent a multidisciplinary diagnostic approach by color Doppler ultrasonography, dynamic pharmacocavernosometry (optional), selective pudendal pharmaco-arteriography (optional) and nocturnal penile tumescence monitoring by a Rigi-Scan (optional). Mean age of the population was 32 years. Psychogenic impotence was diagnosed in 50% of the patients and organic impotence was diagnosed in 45%. After the 3rd decade of life, a vasculogenic etiology was the most common cause of impotence. Smoking and hypertension played a major role as chronic contributing factors in the overall study population. Primary impotence was diagnosed in 11 patients who were unmarried. The rate of organic causes was 45% in this group (all vasculogenic in nature). Erectile dysfunction in younger patients and in patients with primary impotence is due mainly to organic causes, usually vascular in origin.

Objectives: Measurement of urine fibrin-fibrinogen degradation products has been reported to be a useful marker for bladder malignancies. This is a simple, noninvasive and rapid method in the diagnosis and follow-up of bladder cancer. We performed a prospective study to evaluate the reliability of the Accu-Dx test which detects urinary fibrin and fibrinogen products associated with bladder cancer., Material and Methods: 97 patients were included in this study. 55 patients with bladder cancer were under surveillance, and 35 were evaluated as primary cases. The Accu-Dx test was performed in 7 additional patients presenting with hematuria due to benign disorders. Urine cytology specimens were collected in all, whereas bladder pathology specimens were obtained in 93. The Accu-Dx test was evaluated with regard to the results of urine cytology and pathological assessment, which constituted the gold standard., Results: According to pathology, 69 patients had carcinoma of the bladder. In 48 (69.6%), the Accu-Dx test was positive whereas urine cytology was positive in only 31 (44.9%; p<0.001). Specificity rates were 67.9 and 96.4%, respectively. With higher stages and higher tumor grades, the Accu-Dx test yielded higher positive rates (50% in Ta versus 100% in T2 or higher and 42.9% in G1 versus 94.1% in G3). On the other hand, the test was positive in 6 patients with cystitis of various etiologies. The overall accuracy rate for Accu-Dx was 69%., Conclusions: The Accu-Dx test is a simple, rapid, reproducible and more importantly a noninvasive method in the detection of bladder malignancies. But it seems inadequate to replace conventional cystoscopy plus pathologic assessment due to its relatively low accuracy and specificity rates. It may be helpful in selecting patients who should be evaluated with rigid endoscopes together with bladder biopsies.

Objective: The aim of this prospective study was to assess the reliability of nocturnal penile tumescence monitoring by an ambulatory RigiScan device in the etiological diagnosis of erectile dysfunction., Patients and Methods: A total of 64 randomized patients with a complaint of impotence for at least 6 months initially underwent nocturnal penile tumescence rigidity (NPTR) monitoring on 2 consecutive nights in a private setting as session 1. All subjects then underwent a comprehensive multidisciplinary diagnostic approach including dynamic color Doppler sonography and pharmaco-cavernosometry as a second session in a blind fashion. The results of both sessions were compared with each other., Results: Sensitivity, specificity, positive predictive value and accuracy rate of NPTR monitoring in discriminating organic from psychogenic impotence with respect to a multidisciplinary diagnostic approach using sophisticated techniques were as 80.9, 81.8, 89.4 and 81.2%, respectively., Conclusion: Although RigiScan differentiates organic from psychogenic impotence with a relatively high sensitivity, a multidisciplinary diagnostic approach is mandatory in establishing the ultimate diagnosis.

Objective: To determine the value of a diagnostic and therapeutic approach for patients presenting with acute penis and the effects of this management on the outcome., Patients and Methods: The study comprises 21 consecutive patients (mean age 33.3 years, range 19-53) who presented with acute penis (acute pain and swelling during and soon after intercourse). The mean interval between the accident and the treatment was 6 h (range 2-20). All patients initially underwent cavernosography, followed by surgical exploration., Results: Cavernosography showed extravasation of the contrast medium, indicating a corporal tear, in 19 of 21 patients. Surgical exploration revealed rupture of the deep dorsal vein in two patients whose radiological examinations were normal. In the remaining 19 patients, corporeal tears were repaired. The mean follow-up was 26.7 months; all patients regained penile function (potency). Penile curvature was the only adverse effect in three of the 21 patients, all of whom presented for medical treatment relatively late after the initial accident., Conclusion: In the management of the acute penis, cavernosography should be performed first and the treatment policy should be determined from the radiological findings. Conservative therapy should be chosen only when the corporeal bodies are intact.

This prospective study was designed to compare the parameters obtained by color Doppler ultrasound to cavernous artery occlusion pressure measured by dynamic pharmacoinfusion cavernosometry in evaluating arterial components of erectile dysfunction. Four indexes were determined as parameters of sonography to indicate arterial competence. Indexes 1 and 2 reflected peak systolic velocities with respect to the cut-off values 25 and 30 cm/s after pharmacological stimulation with 60 mg papaverine hydrochloride respectively. Index 3 was the percentage of diameter changes in cavernosal arteries which was expected to be > 75%. The sum of the percents of increases in diameters of both cavernosal arteries which should be > 200, formed index 4. The sensitivity, specificity, positive predictive value and accuracy rates were 76, 100, 100 and 90% for index 2. These values were 50, 100, 100 and 71% for index 1. Very low statistical values were obtained for indexes 3 and 4. Although the gold standard in the diagnosis of arterial impotence is pharmacoangiography, color Doppler sonography using the parameter peak systolic flow rate > 30 cm/s may be a reliable, easily obtained, noninvasive technique for evaluating arterial components of erectile dysfunction.

The aim of this prospective study was to compare the effectiveness of colour Doppler ultrasound and testicular scintigraphy in the differential diagnosis of acute scrotum. Ten patients were investigated by clinical examination initially and by both techniques afterwards. Scintigraphy was performed in a blind fashion. According to the findings, 3 patients were categorized as acute ischaemia and 7 as inflammation. The 3 patients diagnosed as ischaemia underwent surgical exploration. Both imaging techniques predicted ischaemia (100%). In the inflammation group conservative therapy and follow-up were chosen. Ultrasonography alone established the correct diagnosis in 7/7, whereas scintigraphy in 5/7 of the patients.

Objectives: Prior animal studies have shown through direct pressure measurements that there is a definite rise in the renal vascular resistance in obstruction. Therefore intrarenal hemodynamic changes can be determined by the vascular impedance expressed as pulsatility and resistive indexes (PI and RI) obtained from the Doppler waveforms of intrarenal arteries. We investigated whether various degrees of obstruction result in different hemodynamic responses according to color Doppler sonography., Methods: 22 kidneys with varied degrees of hydronephrosis and 19 normal kidneys were examined. The pulsatility and resistive index of Doppler waveforms from interlobar arteries were obtained. The grade of hydronephrosis was based upon the width of parenchyma., Results: The mean resistive index in the study and controls were 0.70 +/- 0.07 and 0.60 +/- 0.03, respectively. The difference was significant (p < 0.001). Pulsatility indexes in the study and controls were 1.07 +/- 0.34 and 0.98 +/- 0.23, respectively. The difference was not significant (p > 0.005). Significant difference was also noticed in the parenchymal widths between both groups (p < 0.001)., Conclusion: It appeared that intrarenal color Doppler sonography can provide physiologic information reflecting renal vascular resistance status by means of an easily obtained parameter: resistive index.

Cavernous tissues of 27 impotent and 4 potent men were evaluated in order to determine the ultrastructural changes in patients with vasculogenic impotence. Tissue samples were obtained during penile prosthesis insertions and surgical repairs of penile fractures in impotent and potent patients, respectively. For the clinical evaluation (pharmacologic color Doppler ultrasound, dynamic pharmacocavernosometry and nocturnal penile tumescence monitoring) patients were divided into three groups: slight/moderate arterial dysfunction (n = 5), severe arterial dysfunction (n = 9) and purely cavernous erectile dysfunction (n = 9). No significant ultrastructural alteration was noticed in the group with moderate arterial dysfunction; decrease and deterioration of smooth muscle cells was the prominent finding in the severe arterial and venogenic dysfunction groups. Preliminary examination of cavernous tissue may be a part of routine evaluations in the approach to the management of erectile dysfunction.

The gold standard in the diagnosis of venous impotence is cavernosometry. But a less invasive and time-consuming screening test for patients with a high probability of venous impotence is required. Therefore we evaluated 82 men with erectile dysfunction by color Doppler sonography after intracavernosal injection of 60 mg papaverine. 28 of them who had a poor erectile response but sufficient arterial inflow were included in this study. 6 patients who were previously found to have psychogenic impotence formed the control group. After pharmacological stimulation by papaverine, all patients were examined for 20 min by color Doppler sonography in order to detect diastolic flow velocities in the cavernosal arteries and erectile responses. Both groups of patients underwent pharmaco-cavernosometry in a blind fashion afterwards. The diagnosis of venous impotence with color Doppler sonography was confirmed by dynamic pharmaco-cavernosometry in 25 of 28 (89%) and 6 of 6 (100%) subjects of the study and control groups, respectively. Statistically, in the diagnosis of venous dysfunction, color Doppler sonography had a sensitivity of 100%, specificity of 66.6%, accuracy rate of 91% and a positive predictive value of 0.892. The gold standard in the diagnosis of venous impotence is still cavernosometry, but it seems that color Doppler sonography may provide a sensitive assessment of penile venous competence.