Thermo-elastic gigahertz-frequency oscillator through surface acoustic wave-silicon photonics.

Opto-electronic oscillators are sources of microwave-frequency tones that may reach very low noise levels. Much effort is being dedicated to the realization of oscillators based on photonic integrated devices. In this work, we propose and demonstrate a thermo-elastic opto-electronic oscillator at 2.

Surface acoustic wave photonic devices in silicon on insulator.

Opto-mechanical interactions in planar photonic integrated circuits draw great interest in basic research and applications. However, opto-mechanics is practically absent in the most technologically significant photonics platform: silicon on insulator. Previous demonstrations required the under-etching and suspension of silicon structures.

Electrochemical Quartz Crystal Microbalance with Dissipation Real-Time Hydrodynamic Spectroscopy of Porous Solids in Contact with Liquids.

Using multiharmonic electrochemical quartz crystal microbalance with dissipation (EQCM-D) monitoring, a new method of characterization of porous solids in contact with liquids has been developed. The dynamic gravimetric information on the growing, dissolving, or stationary stored solid deposits is supplemented by their precise in-operando porous structure characterization on a mesoscopic scale. We present a very powerful method of quartz-crystal admittance modeling of hydrodynamic solid-liquid interactions in order to extract the porous structure parameters of solids during their formation in real time, using different deposition modes.

[Diagnostic image (91). A collapsing man with an aortic aneurysm. Ruptured aneurysm of the abdominal aorta].

A 73-year-old man had been diagnosed with an abdominal aortic aneurysm. Surgery was impossible due to poor cardiopulmonary condition. The patient collapsed due to rupture of the aneurysm.

A rational approach to dose reduction in CT: individualized scan protocols.

The aim of this study was to demonstrate that dose reduction and constant image quality can be achieved by adjusting X-ray dose to patient size. To establish the relation between patient size, image quality and dose we scanned 19 patients with reduced dose. Image noise was measured.

[Diagnostic image (60) Chilaiditi syndrome].

In a 27-year-old man in whom an X-ray of the thorax was made, Chilaiditi syndrome (interposition of the colon between diaphragm and the liver) was diagnosed.

[Diagnostic image(58). Renal cell carcinoma].

In a 38-year-old man with flank pain and macroscopic haematuria, CT revealed a renal mass of which the pathology diagnosis was: primary renal cell carcinoma.

Von Hippel-Lindau disease: strategies in early detection (renal-, adrenal-, pancreatic masses).

Von Hippel-Lindau disease (VHL) is a hereditary syndrome characterized by a predisposition for bilateral and multicentric retinal angiomas, hemangioblastomas in the central nervous system (CNS), renal cell carcinomas, pheochromocytomas, islet cell tumors of the pancreas, and endolymphatic sac tumors, as well as cysts in the kidney, pancreas, and epididymis. This review focuses on developments in imaging of renal, adrenal, and pancreatic masses in VHL. Radiology still has a central place in managing of VHL.

Management of renal cell carcinoma in von Hippel-Lindau disease.

Background: An evaluation of nephron-sparing surgery (NSS) or radical nephrectomy (RN) for treating renal cell carcinoma (RCC) in patients with von Hippel-Lindau disease (VHL) was carried out.

Methods: Between 1976 and 1997, 10 patients with RCC from four VHL families, of whom seven were from one family, were studied by clinical and histopathological examination. Before 1991, three patients were treated using RN, and thereafter five patients were treated using NSS.

Added value of CT criteria compared to the clinical SAP score in patients with acute pancreatitis.

Background: To assess the added value of established computed tomography (CT) scores versus the Simplified Acute Physiology (SAP) score in predicting outcome in patients with acute pancreatitis.

Methods: Contrast-enhanced CT was performed in 45 patients with acute pancreatitis. The Balthazar score, CT severity index (CTSI), and Schröder score were assessed, and the SAP score was calculated.

Digital chest imaging using a selenium detector. The impact of hard copy size on observer performance: a computed tomography-controlled study.

Rationale And Objectives: The authors compare radiologist detection performance under clinical conditions for assessment of the effect of size reduction on the diagnostic performance of digital chest images obtained with a selenium detector.

Methods: Sixty-five patients were examined with the digital system. The images were acquired without an antiscatter grid.

Radiation-induced brachial plexopathy: MR imaging.

Objective: To describe the MR imaging appearance of radiation-induced brachial plexopathy.

Design: MR imaging was performed in two patients with the clinical diagnosis of radiation-induced brachial plexopathy and in one with surgically proven radiation fibrosis of the brachial plexus.

Patients: Three patients who had had radiation therapy to the axilla and supraclavicular region (two with breast carcinoma and one with Hodgkin's lymphoma) presented with symptoms in the arm and hand.

Magnetic resonance imaging of the brachial plexus in patients with multifocal motor neuropathy.

We studied whether magnetic resonance (MR) imaging of the brachial plexus is useful to distinguish multifocal motor neuropathy (MMN) from lower motor neuron disease (LMND) and whether abnormalities resemble those of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). We compared MR images of the brachial plexus of nine patients with MMN with scans from five patients with CIDP, eight patients with LMND, and 174 controls. In two patients with MMN, and in three patients with CIDP, the MR images showed an increased signal intensity on the T2-weighted images of the brachial plexus.

CT prediction of irresectability in esophageal carcinoma: value of additional patient positions and relation to patient outcome.

Background: To improve computed tomographic (CT) prediction of local irresectability and to correlate preoperative CT findings with patient outcome.

Methods: Eighty-five patients with esophageal carcinoma underwent CT in supine, left lateral decubitus, and prone positions. CT signs that were indicative of local irresectability included (1) an angle of contact >45 degrees with the aorta; (2) obliteration of triangular fat pad between the tumor, aorta, and spine; (3) tumor contiguous with the aorta in all three positions; and (4) indentation of the airway in all three positions.

Focal liver lesions: characterization with triphasic spiral CT.

Purpose: To assess whether triphasic spiral CT enables characterization of a wide range of focal liver lesions.

Materials And Methods: One hundred five patients with suspected focal liver disease underwent triphasic liver CT. After injection of contrast material, the liver was scanned in arterial (scanning delay, 22-27 seconds), portal (scanning delay, 49-73 seconds), and equilibrium (scanning delay, 8-10 minutes) phases.

Chest imaging with a selenium detector versus conventional film radiography: a CT-controlled study.

Purpose: To compare radiologist detection performance under clinical conditions for assessment of conventional radiographs and digital chest images obtained with a selenium detector.

Materials And Methods: One hundred four patients were examined with the digital and conventional systems under near identical technical conditions. The digital images were acquired without an antiscatter grid.

Effects of dose reduction on digital chest imaging using a selenium detector: a study of detecting simulated diffuse interstitial pulmonary disease.

Objective: The purpose of this study was to evaluate the effect of dose reduction on the diagnostic performance of a new digital chest imaging system in which amorphous selenium is used as the X-ray detector. Diagnostic performance was assessed for the detection of simulated diffuse interstitial pulmonary disease (DIPD).

Materials And Methods: DIPD was simulated by superimposing plastic sheets that contained small radiopaque objects (birdseed) on an anthropomorphic chest phantom.

From medical history and biochemical tests to presymptomatic treatment in a large MEN 2A family.

An extensive study was published in 1959 in the Netherlands on a large family, which initially attracted attention because of a family history of attacks of shaking. Clinical investigation revealed phaeochromocytomas in four family members. In 1975, the family was identified to be a MEN 2A family, and since then, the members were examined annually using measurement of catecholamine metabolites in 24-h excreted urine and C-cell stimulation tests.

Digital chest imaging with a selenium detector: comparison with conventional radiography for visualization of specific anatomic regions of the chest.

Objective: The purpose of this study was to compare a new digital chest radiography system that uses amorphous selenium as the X-ray detector with conventional radiography for the visualization of various anatomic regions of the chest as a first phase of testing image quality.

Materials And Methods: Six observers analyzed pairs of posteroanterior chest radiographs of 40 patients. One radiograph in each pair was obtained with a conventional chest film changer, and the other was obtained with the digital selenium chest radiography system.

Planning of liver surgery using three dimensional imaging techniques.

In the simplified Couinaud classification, in which the liver is divided into eight segments, each supplied by a central vasculo-biliary sheath, little attention is given to the high prevalence of anatomical variations which occur, especially in the right hemiliver. Using volumetric acquisition techniques, such as magnetic resonance imaging or spiral computed tomography scanning, detailed insight into the individual segmental anatomy can now be obtained in a non-invasive manner. The significance of this anatomical insight lies in the planning of anatomical resections, whereby the relationship between tumour and individual segmental anatomy can be depicted in a three-dimensional format.

Portal venous and segmental anatomy of the right hemiliver: observations based on three-dimensional spiral CT renderings.

Objective: The purpose of this study was to evaluate the segmental anatomy of the right hemiliver and to assess whether the right hepatic vein and right portal trunk are accurate indicators of the position of the right and transverse scissurae, respectively.

Subjects And Methods: We examined 26 patients with spiral CT using 5-mm slices, reconstructed at 2-mm intervals. Three-dimensional renderings of the portal and hepatic venous structures were created.

Von Hippel-Lindau disease: new strategies in early detection and treatment.

Unlabelled: Von Hippel-Lindau disease is an autosomal dominant inherited disorder causing hemangioblastomas of the central nervous system (CNS), retinal hemangiomas, renal cell carcinomas, pheochromocytomas, pancreatic and liver cysts, and epididymal cystadenomas.

Purpose: Since 1976, we have periodically screened for the lesions in a large affected family and were able to evaluate new strategies in detection and treatment.

Patients And Methods: A total of 23 individuals underwent the screening program.

Variations in venous and segmental anatomy of the liver: two- and three-dimensional MR imaging in healthy volunteers.

Objective: The purpose of this study was to use two- and three-dimensional analysis of thin-slice MR imaging data to study the anatomic variations in the segmental anatomy of the liver. It is important to recognize these anatomic variations in order to ensure accurate localization of hepatic lesions and preoperative delineation of resection planes.

Subjects And Methods: T1-weighted MR images of contiguous 4-mm sections were obtained in 10 healthy subjects.

Retroperitoneal cystic lymphangioma section imaging in two cases, and review of the literature.

Two patients with retroperitoneal cystic lymphangioma are reported with a review of the medical literature. In one, the patient was asymptomatic from the lesion but had a computed tomography (CT) and an ultrasound to evaluate the extent of disease with a known carcinoma of the colon. The second patient presented with an acute abdominal pain requiring surgical management.