Showing papers in "Rays in 2003"

Selection and delineation of target volumes in head and neck tumors: beyond ICRU definition.

Abstract: Implementation of three-dimensional conformal radiotherapy (3D-CRT) and intensity modulated radiation therapy (IMRT), which permits far greater control of dose distribution, requires proper selection and delineation of target volumes, and adequate control of setup uncertainties. The present manuscript intends to review available data on selection and delineation of target volumes for primary tumor and neck nodes. Setup uncertainties and how they influence the PTV delineation are also discussed.

Picture archiving and communication in radiology

Abstract: After over 80 years of exclusive archiving of radiologic films, at present, in Radiology, digital archiving is increasingly gaining ground. Digital archiving allows a considerable reduction in costs and space saving, but most importantly, immediate or remote consultation of all examinations and reports in the hospital clinical wards, is feasible. The RIS system, in this case, is the starting point of the process of electronic archiving which however is the task of PACS. The latter can be used as radiologic archive in accordance with the law provided that it is in conformance with some specifications as the use of optical long-term storage media or with electronic track of change. PACS archives, in a hierarchical system, all digital images produced by each diagnostic imaging modality. Images and patient data can be retrieved and used for consultation or remote consultation by the reporting radiologist who requires images and reports of previous radiologic examinations or by the referring physician of the ward. Modern PACS owing to the WEB server allow remote access to extremely simplified images and data however ensuring the due regulations and access protections. Since the PACS enables a simpler data communication within the hospital, security and patient privacy should be protected. A secure and reliable PACS should be able to minimize the risk of accidental data destruction, and should prevent non authorized access to the archive with adequate security measures in relation to the acquired knowledge and based on the technological advances. Archiving of data produced by modern digital imaging is a problem now present also in small Radiology services. The technology is able to readily solve problems which were extremely complex up to some years ago as the connection between equipment and archiving system owing also to the universalization of the DICOM 3.0 standard. The evolution of communication networks and the use of standard protocols as TCP/IP can minimize problems of data and image remote transmission within the healthcare enterprise as well as over the territory. However, new problems are appearing as that of digital data security profiles and of the different systems which should ensure it. Among these, algorithms of electronic signature should be mentioned. In Italy they are validated by law and therefore can be used in digital archives in accordance with the law.

Lymphatic drainage and CTV in carcinoma of the prostate.

Abstract: The prostate lymphatics drain into the periprostatic subcapsular network, from which 3 groups of ducts originate: the ascending ducts from the cranial prostate draining into the external iliac lymph nodes, the lateral ducts running to the hypogastric lymph nodes and the posterior ducts draining from the caudal prostate to the subaortic sacral lymph nodes of the promontory. Internal, external iliac and obturator lymph nodes are the most frequently involved by prostate carcinoma. Metastases to presacral and common iliac lymph nodes are rare. For the limited staging accuracy, present indications for seminal vesicle irradiation and pelvic node prohylactic irradiation are essentially based on risk categories and estimation algorithms; the latter while are widely used in international studies are not free of limitations as stressed since they were introduced. A method to deliver high doses to the tumor while limiting the irradiation of critical organs might be the delivery of a boost to the tumor only. This approach could become increasingly feasible with the diffusion of imaging procedures able to better define tumor extension.

Underlying anatomy for CTV contouring and lymphatic drainage in rectal cancer radiation therapy.

Abstract: Despite the low local recurrence rate that can be achieved by adequate surgery (total mesorectal excision--TME), radiation therapy was shown to play a significant role in reducing this risk The widespread use of TME in many European Centers has introduced a new terminology and the need to identify the area at major risk for local failure using this surgical procedure In the surgical series where extended extra-mesorectal surgery was performed, the role of lymphatic spread was evidenced, especially for low rectal cancer, through the pelvic parietal fascia and lateral pelvic spaces The aim of this study was to better define some anatomic concepts and the main risk factors which impact on CTV contouring and field conformation in rectal cancer treatment This information helps formulating guidelines for CTV contouring in daily radiotherapy practice, in order to define the best therapy, according to the tumor stage and location

Diffusion and perfusion MR imaging.

Abstract: Diffusion (DWI) and perfusion weighted (PWI) MR imaging, have come to have an increasingly important clinical role, especially in neurovascular imaging. Diffusion MR imaging does not evaluate hemodynamic parameters, but can be considered a functional technique because it provides information about the tissue functional structure at a microscopic level. In this technique, image contrast to a large extent depends on the diffusion coefficient, a parameter indicative of the characteristics of the stochastic thermic translational motion of water molecules (Brownian motion). Clinical perfusion measurement has been performed in almost all organs with different techniques. Over the last ten years, with the use of contrast media, considerable experience has been gained in the measurement of hemodynamics with MRI. At present, perfusion-MR imaging is one of the clinically most relevant procedures of functional MRI, whose application is gaining ground, owing to the increasing availability of necessary hardware and software. Physical and hemodynamic principles of the two techniques, pulse sequences necessary for their implementation and main applications in the imaging of CNS disorders are illustrated. While DWI and PWI alone can address numerous questions, their information is for the most part complementary to that provided by conventional MRI and their combination seems extremely promising.

IHE: integrating the healthcare enterprise, towards complete integration of healthcare information systems.

Abstract: Information systems of a modern hospital govern extremely important functions as patient management, control of work flows, administration etc. However a great variety of recommended standards are used while in most cases no effective coordination and intercommunication is possible. Some years ago to simplify and resolve this problem IHE was created; it is a technical framework which identifies a number of components of the healthcare enterprise (the "actors") whose interactions are defined in terms of "transactions", that should be implemented according to HL7 and DICOM standards. Attempting an in-depth understanding of IHE structure and its principles of function, those transactions that can occur among the various actors, which of these are supported and which require specific actors, are analyzed. IHE is continuously evolving, therefore open to the factual contribution of all health professionals who can point out the main instances that emerge daily from their activity in the field. While its origin was specific for the field of radiology, the true soul and driving force of the project lay on the type of approach used: to get together medical specialists and information technology professionals in order to identify and solve the difficulties which hindered an effective and functional integration of healthcare information systems.

Web-based radiology: a future to be created.

Abstract: The impact of Internet on Medicine and Surgery is certainly remarkable, however the influence it had on Diagnostic Imaging was even stronger. The standardization of digital images acquired by the different medical imaging equipment has further facilitated the diffusion, transmission and communication in radiology within hospitals as well as on WEB. Radiology departments are bound to become "filmless" and with the present "tablet PC" radiological images will be directly transferred to the patient's bed in the relative electronic patient report. For radiology, interactive education could be envisaged with a tutor who guides the student(s) through the network. The Internet is an inexhaustible source of radiologic educational and information material with a number of sites of clinical cases, tutorial and teaching files, journals and magisterial lectures on-line. In a near future, the Internet could be applied in the simulation of clinicoradiologic cases or in applications of artificial intelligence with expert systems to support the solution of most complex cases.

Target definition and contouring in carcinoma of the lung and esophagus.

Abstract: The optimal treatment for intrathoracic tumors such as lung and esophageal cancer requires an improvement of therapeutic ratio to increase efficacy of the cancer-cell kill and decrease the normal-cell kill. This is not an easy task because sensitive normal cells such as alveoli and epithelial cells in the esophagus and bronchus surround these tumors. How to minimize the damage of such sensitive normal cells within irradiated fields without sparing cancer cells is a major issue for radiation oncologists, especially as concurrent chemoradiotherapy has become more standard treatment. One way to achieve this task is accurate delineation of the target volume, which will be emphasized here. Some other ways to achieve it are biological protection by ethyol, keratinocyte growth factors, biologically targeted treatments such as C225 and celecoxib, and anti-angiogenesis, which have been briefly addressed in Dr. Cox's article in this Journal. Molecular imaging is a new diagnostic and therapeutic modality that offers great potential for accuracy of target definition, although it is not quite ready for routine clinical use at the present time. Accurate target definition and contouring in cases of carcinoma of the lung and esophagus depend on expertise of diagnostic and therapeutic medical teams. There we review the normal anatomy, diagnostic methods, and tumor delineation of cancer of the lung and esophagus.

Uncertainties in physical and biological targeting with radiation therapy.

Abstract: Advances in radiation therapy over the past decade have resulted from increased accuracy of imaging and highly conformal three dimensional treatment planning and delivery of radiation therapy. Three-dimensional conformal radiation therapy (3D CRT) with higher doses than previously considered tolerable is now standard for many types of cancer. Intensity modulated radiation therapy (IMRT) with x-rays, proton beam treatments and intensity modulated proton therapy (IMPT) are major areas of research. Tumor motion between and even during radiation treatments represents a major uncertainty. Tumor heterogeneity results in additional uncertainties affecting tumor control with radiation therapy. Imaging the heterogeneous targets within tumors offers new opportunities for tumor delineation. Molecular therapeutic agents enhance the effects of ionizing radiations in murine systems. Clinical trials combining molecular targeting agents with conformal radiation therapy are being initiated.

Information systems in the management of the radiology department.

Abstract: Clinical, organizational and administrative service improvement has always been the primary aim of a radiology information system. Studies carried out at Massachusets General Hospital in the late sixties identified two "bottlenecks" in the Departments of Diagnostic Imaging: the planning of examinations and the management of picture archiving. Therefore, the information system started to be viewed as a potential tool for the solution of these problems. In time, the concept of Radiology Information System (RIS) was conceived. With its developments it is now considered an effective support for the daily activity of the Radiology department, to tackle and solve the operational problems posed by the various healthcare professionals. A radiology information system essentially concerns three functional areas: the patient management, the procedure management, the department management. Another major task of RIS is represented by its integration with the other information systems of Radiology and hospital to enable to share information in real time with the hospital information system (HIS) and the other information systems (system of first-aid management, intensive therapy units etc). A modern RIS must be in conformance with DICOM 3 for the service class of the working list to be able to transmit to the diagnostic imaging equipment the patient correct names and demographics and the type of procedure to be performed.

Post-processing of digital images.

Abstract: Post-processing of bi- and three-dimensional images plays a major role for clinicians and surgeons in both diagnosis and therapy. The new spiral (single and multislice) CT and MRI machines have allowed better quality of images. With the associated development of hardware and software, post-processing has become indispensable in many radiologic applications in order to address precise clinical questions. In particular, in CT the acquisition technique is fundamental and should be targeted and optimized to obtain good image reconstruction. Multiplanar reconstructions ensure simple, immediate display of sections along different planes. Three-dimensional reconstructions include numerous procedures: multiplanar techniques as maximum intensity projections (MIP); surface rendering techniques as the Shaded Surface Display (SSD); volume techniques as the Volume Rendering Technique; techniques of virtual endoscopy. In surgery computer-aided techniques as the neuronavigator, which with information provided by neuroimaging helps the neurosurgeon in simulating and performing the operation, are extremely interesting.

Molecular imaging: state of the art.

Abstract: Molecular imaging includes all imaging methods applied in the identification, characterization and assessment "in vivo" of biological processes which occur at the cellular and molecular level. Molecular imaging parallels the remarkable advances achieved in the medical field, culminated in the sequencing of human DNA, the genome project. The understanding of the genetic basis of diseases and of human biology in general, together with the development of new drugs, led to a growing need for novel, sensitive and safe imaging technology to be rapidly translated from animal models into patients. The present evaluation of presence/absence of disease is based on anatomic and morphologic changes, the result of underlying molecular alterations. Direct "in vivo" visualization of these alterations allows early diagnosis before the onset of typical pathologic manifestations. Similarly, short-term effects of therapy can be directly visualized. In a near future, "evidence-based" medicine will become "presymptomatic" medicine. Histopathology will be replaced by "molecular pathology" with genomic implications in disease classification. In the near future the conventional morphologic methods should be supported and then replaced by the new functional and molecular methods with additional information proved useful for the diagnostic approach. In this article, the potentialities and applications of Nuclear Medicine, Magnetic Resonance Imaging, Optical Imaging and Contrast-enhanced Ultrasound are reviewed.

Preoperative radiotherapy in gastric cancer: CTV definition for conformal therapy according to tumor location.

Abstract: In the past radiation oncologists had not a major interest in the treatment of gastric cancer, but the positive outcomes of the Intergroup Study (INT-0116) supported the role of locoregional control in promoting better survival. To reduce the toxicity and the risk of residual disease in locally advanced tumors after surgery,a preoperative approach was tentatively considered. The aim of this manuscript is to define the location of nodal area at risk for cancer involvement according to the tumor location (cardias, corpus, antrum) on CT images to help the radiotherapist in the contouring process of the CTV for preoperative conformal treatment of gastric cancer. The analysis of both the percentage of nodal involvement detected at surgery and of the site of recurrence after radical surgery can direct to the areas to be considered at risk with its contouring on CT. Preoperative conformal-three dimensional radiotherapy of gastric cancer requires clear and well defined contouring guide-lines to allow the evaluation of clinical outcomes and the analysis if the area at risk for recurrence has changed after the preoperative approach.

Uncertainties in radiation therapy: target volume definition in prostate cancer.

Abstract: Accurate definition of target volumes and pelvic organs at risk is critical to improve the outcome in patients treated with irradiation for localized carcinoma of the prostate. Precise delineation of these structures will assist in more rational therapeutic decisions and optimized radiation therapy treatment planning and delivery. Increased conformity in radiation dose distribution allows delivery of higher doses of irradiation and dose escalation studies and results in improved tumor control, lower incidence of distant metastasis, improved survival and better quality of life. Multiple imaging methods are available and significant advances have been made in image fusion to enhance target volume definition. An exhaustive review of the literature is presented.

Evolution of digital angiography systems.

Abstract: The innovations introduced by digital subtraction angiography in digital radiography are briefly illustrated with the description of its components and functioning. The pros and cons of digital subtraction angiography are analyzed in light of present and future imaging technologies. In particular, among advantages there are: automatic exposure, digital image subtraction, digital post-processing, high number of images per second, possible changes in density and contrast. Among disadvantages there are: small round field of view, geometric distortion at the image periphery, high sensitivity to patient movements, not very high spatial resolution. At present, flat panel detectors represent the most suitable substitutes for digital subtraction angiography, with the introduction of novel solutions for those artifacts which for years have hindered its diagnostic validity. The concept of temporal artifact, reset light and possible future evolutions of this technology that may afford both diagnostic and protectionist advantages, are analyzed.

Lymphatic drainage and CTV in pancreatic carcinoma.

Abstract: CTV definition in exclusive or adjuvant radiation therapy of pancreatic carcinoma is essentially based on the opinion of "expert" authors and on the knowledge of lymphatic pathways. The subject has been widely debated. Radiotherapy treatments of the entire upper abdomen (liver and pancreatic region), pancreas and lymph node stations, to volumes focused on macroscopic tumor only, have been proposed. Carcinoma of exocrine pancreas is characterized by the frequent, early appearance of metastasis via the lymphatic route. Most commonly involved lymph node stations include those of the celiac trunk, superior mesenteric, peripancreatic, lumboaortic lymph nodes, those of the hepatic portal (the latter in particular for pancreatic head tumors) and of the hilum of spleen (the latter in particular for pancreatic tail tumors). The possible multicentricity of pancreatic carcinoma, most likely due to intraductal spread, should lead to the inclusion in the CTV of the entire pancreatic parenchyma. This should be considered also for the frequent perineural intra- or extrapancreatic spread of pancreatic carcinoma present also in small tumors (T1). In extrapancreatic spread the retropancreatic adipose tissue should be included in the CTV at least at the GTV level. At the present state of knowledge, in the absence of pattern of failure analysis and of comparison of different treatment approaches, in terms of the definition of volumes of interest, CTV definitions which include lymphatic drainage stations, most part of pancreatic parenchyma and retropancreatic adipose tissue seem justified especially in treatments for cure. In palliation, the CTV may be limited to the GTV and the adipose tissue behind it.

Diagnostic imaging and therapy in a case of myasthenia gravis associated with thymic hyperplasia.

Abstract: The diagnostic approach to a patient with myasthenia gravis to verify the presence of thymic hyperplasia/thymoma is presented. The study of the mediastinal region was necessary. Mediastinal MRI showed the presence of a mass. The differential diagnosis between a mediastinal and an extramediastinal lesion is possible with MRI for its high contrast resolution, good spatial resolution and multiplanarity that allow the detection, localization, evaluation of the extent and/or infiltration of adjacent tissues/organs based on the analysis of adipose cleavages and typing in the different pulse sequences of pathologic tissue with contrast enhancement. Definitive diagnosis of thymic hyperplasia was established. Therefore surgery should be essentially associated with the severity of the clinical presentation rather than with thymic hyperplasia.

Diagnostic and therapeutic imaging in a case of cervical pregnancy. Clinical aspects and ethical implications.

Abstract: A case of a 37-year-old, 8 week pregnant woman come to the emergency service with the diagnosis of cervical pregnancy an metrorrhagia, is reported. Uterine artery embolization was performed to arrest the bleeding. BCF monitoring documented its disappearance after approximately 15 days with progressive decrease in serum beta-hCG levels. Once the death of the fetus was ascertained, placental detachment was facilitated with the administration of methotrexate therapy. In view of the curettage of the uterine cavity a second uterine artery embolization was performed. Twenty days after the diagnosis of abortion, curettage was performed and the patient could be discharged. The combined action of embolization, methotrexate therapy and curettage allowed to preserve the potential fertility of the woman.

Virtual simulation: fifteen years later.

Abstract: In the last two decades there was a radical change in radiotherapy setup. The growing availability of CT equipment and console for computer-aided treatment planning setup enabled the use of advanced technologies as conformal 3D radiation therapy in most centers. In particular in 1987 virtual simulation was proposed for setup. During its use a number of application modalities appeared. Virtual simulation in some centers is applied alone while in others it is associated with conventional simulation. However, from numerous reports published in last years it seems that virtual simulation significantly improves treatment quality independently of radical or palliative intent and of the size of treated volumes (high doses to small volumes or wide shaped fields). Some studies stressed that virtual simulation could significantly shorten treatment planning times with consequent cost reduction. The use of virtual simulation evidenced associated problems and in particular setup limitations due to the CT gantry size, the need to up-date the conventional modalities of setup verification according to the new technologies and more generally to up-date quality assurance procedures in an advanced technological setting. Finally there was the self-evident need of a better knowledge of the anatomy on axial sections, of tumor spread routes in particular.

Combined diagnostic imaging of adenomyomatosis of the gallbladder.

Abstract: The consistency of a request for liver MRI and MR-cholangiopancreatography in a patient with an occasional US-finding of mural thickening of gallbladder fundus > or = 3 mm in size was assessed. The differential US diagnosis in case of focal mural thickening was analyzed in combination with the other findings to justify the radiologicoclinical reliability of the request. Overall, these findings suggested the diagnostic hypothesis of adenomyomatosis, then confirmed by a second level in-depth examination, namely liver MRI and MR-cholangiopancreatography.

Combined diagnostic and therapeutic imaging of hemosuccus pancreaticus

Abstract: The justification of a request of ERCP in a patient with hematobilia, was evaluated, based on the medical history and negative endoscopy findings for gastrocolic bleeding. The diagnostic examination was performed: it confirmed the release of blood from the papilla of Vater, however the definitive diagnosis could not be established; CT, as the examination of first choice was performed. It provided additional information and the diagnosis of aneurysm of the splenic vein apparently non communicating with the main pancreatic duct, was established. Angiography of the splenic artery was performed as the examination of second choice to definitely ascertain the source of bleeding. During the examination, the aneurysm embolization excluded the affected vessel from the circulation and allowed immediate benefit to the patient.

The evolution of digital radiography: from storage phosphors to flat-panel detectors.

Abstract: At present, conventional radiology is being slowly but inexorably replaced by digital radiology. While storage phosphors introduced approximately twenty years ago are now routinely used, flat panel systems are increasingly popular. There are two types of flat panels: those with direct X-ray conversion to electric charge and those where there is initial X photon conversion to visible light from optical amorphous silicon photodiode coupling for conversion to electric charge. The charge is therefore amplified and digital signal conversion is obtained with an analog-to-digital converter. One of the main advantages of Computed Radiography is the separation of image acquisition processing and display. Acquisition systems of digital images with image processing techniques allow the operator to adapt the image characteristics to the clinical requirements. Contrast value and image brightness can be changed soon after acquisition to optimize visualization before printing or transfer to the workstation for postprocessing. Image processing can be interactive, directly on the system consolle. To digital data various processing algorithms can be applied as high spatial frequency enhancement through the construction of the shadow mask. The new digital systems have improved the quality of conventional radiological images as compared to the screen-film and storage phosphor systems with shorter times of procedures and lower exposure dose to patients, while the diagnostic potentialities of the acquired image are enhanced.

Lymphatic drainage, CTV and molecular imaging in non-small cell lung cancer.

Abstract: Prognosis for non-small cell lung cancer (NSCLC) patients who have locally advanced unresectable disease is poor for persistent thoracic disease and development of distant metastasis. In view of the poor rate of local control following conventional radiation therapy, there is a great need for methods to improve its efficacy. Three-dimensional conformal radiation therapy (3DCRT) is a high precision radiotherapy able to deliver higher doses with smaller doses to the surrounding normal tissues. However, the real problem is: "what do I want to treat?" This question is addressed based on the clinical and biological target volume definition. Selection of the CTV is therefore basically the clinical compromise between the most radical possible CTV and the critical normal tissue tolerance. The clinical target volume includes the GTV plus a margin to encompass subclinical or microscopic malignant disease immediately adjacent to it. Standard radiation therapy consists of a dose of 40 Gy to the entire mediastinum, supraclavicular fossa, and ipsilateral hilum, even if there is no evidence of disease in these areas. Despite the high risk of nodal spread in lung cancer, the benefit of additional elective nodal irradiation (ENI) is not proven while it seems to significantly increase the rate of radiation morbidity. Several studies have been published where ENI was systematically omitted. The main arguments for omitting ENI and the principal clinical experiences, are discussed.

Target delineation and treatment planning in breast conserving therapy.

Abstract: The increased utilization of computed tomography based treatment planning and intensity modulated radiation therapy for treatment of breast cancer has yielded many potential advantages. Yet, a complete understanding of at risk tissues and avoidance structures is necessary to appropriately utilize such a conformal treatment design. Designing a treatment that maximizes dose homogeneity to the whole breast while minimizing dose to the lung parenchyma, coronary vessels, and myocardium has the potential to improve long-term morbidity and cosmetic outcome. In this review we discuss the utilization of three dimensional treatment planning and intensity modulation for the treatment of breast cancer. We focus on the delineation of target and avoidance structures in the setting of breast conserving therapy and the techniques utilized to maximize the therapeutic ratio.

Uncertainties in radiation therapy: target definition in carcinoma of the uterine cervix.

Abstract: In treatment of patients with carcinoma of the cervix, as in any other malignant tumor, accurate identification of target volumes is critical to enhance precision of radiation therapy planning and delivery. These results in improved locoregional tumor control lead to lower incidence of distant metastases and improved survival. Also, radiation therapy morbidity is decreased, enhancing quality of life. Various imaging techniques are available to achieve better target delineation and this can be enhanced with image fusion. Available innovative treatment techniques to optimize the use of radiation therapy for these patients are illustrated.

Multirow CT angiography of coronary arteries.

Abstract: The introduction of spiral multislice or multidetector CT (MSCT) has led to significant results in coronary diagnostic imaging. In fact with MSCT, isotropic (cubic voxel) three-dimensional imaging of large volumes (e.g. the entire cardiac volume) was possible in a single breath-hold. Moreover, with dedicated reconstruction algorithms, temporal resolution and scannable volume could be optimized, limiting the artifacts associated with the spiral technique. The quantification of calcium deposits in the coronary walls and, in particular, the morphologic study of these vessels represent an important challenge to this technique. Multislice CT with retrospective gating is now a relevant diagnostic instrument in coronary heart disease; however only most recent CT devices with 16 rows of detectors enable a real solution of problems of spatial (isotropic, submillimetric imaging) and temporal (< 0.5 s rotation time) required for correct identification of stenosis and plaque characterization, which are the two main goals of noninvasive coronary imaging.

Diagnostic imaging of esophageal web.

Abstract: The case of a 79-year-old female patient with chest pain, palpitations and dysphagia is presented The patient was sent to the Diagnostic Imaging department for barium study of the upper digestive tract From the analysis of findings of fast digital imaging the various disorders and diseases that could be responsible for them, were considered All alternative situations (pharyngeal venous plexus, cricopharyngeal muscle, vertebral osteophytosis, thyroid struma etc) were excluded and the diagnostic suspicion led to the diagnosis of esophageal web (thin mucous membrane within the lumen) For diagnostic completion esophagoscopy was performed It confirmed the diagnostic suspicion and allowed treatment by dilatation that resulted in a marked benefit to the patient

Cochlear blood flow modifications induced by anaesthetic drugs in middle ear surgery: comparison between sevoflurane and propofol.

Abstract: Objective --Because it is necessary to maintain controlled hypotension during middle ear surgery in order to avoid bleeding and as it is known that cochlear blood flow (CBF) is related to blood pressure (BP), it is useful to evaluate CBF modifications induced by anaesthetics in order to prevent cochlear damage. The aim of this paper is to evaluate, using laser Doppler flowmetry, which anaesthetic drug, out of sevoflurane and propofol, has the smallest effect on CBF. Material and Methods --Twenty consenting adult patients scheduled for myringoplasty under general anaesthesia for simple tympanic membrane perforation were studied. Patients were divided into two groups: the first group was treated with sevoflurane and the second with propofol. For the first group, CBF measurement was carried out on three different occasions: (i) at a basal low drug dosage; (ii) having increased the drug dosage to a higher level; and (iii) having reduced the drug dosage to the basal low level again. For the second group, CBF measurement was carried out on three different occasions: (i) 10 min after injecting a bolus of propofol; (ii) immediately after a second propofol injection; and (iii) 10 min after a third injection of propofol. A probe was placed over the promontory in order to measure CBF levels. Results --In the subjects treated with sevoflurane, after having increased the drug dosage, BP decreased significantly while CBF did not change significantly. In the subjects treated with propofol we recorded a significant reduction in BP, as well as a decrease in CBF. Conclusion --The results obtained show that sevoflurane has a hypotensive effect without modifying CBF, while propofol, although having a similar effect on BP to sevoflurane, has less of a protective effect on inner ear microcirculation.

Combined diagnostic and therapeutic imaging in the diagnosis of venous sinus thrombosis in postpartum patients.

Abstract: The case of a woman on day four post partum with sensorimotor deficit of the right side and CT evidence of a left temporofrontal hemorrhagic lesion, is presented. Attending physicians requested cerebral angiography. To better evaluate the clinical justification of requested imaging procedure the patient medical history and performed CT examination were carefully revised. According to this analysis and based on a clinicoradiological methodology, the request of a cerebral angiography was considered appropriate. The examination showed several radiological signs but a definitive diagnosis could not be established. Second choice imaging procedures were analyzed and MRI completed with MR-angiography was performed. It allowed to document transverse and sigmoid sinus thrombosis. Therefore, in the diagnosis of venous sinus thrombosis, MRI combined with MR-angiography was shown to be a method of first choice while angiography plays a major role in therapy for intravascular thrombolysis.

Computer-aided diagnosis.

Abstract: The evolution of logic thought in relation to the predominant recent advances in technology is analyzed. In fact, the computer was the prime mover of this major change. At present the use of sophisticated software has allowed to attain increasingly accurate levels of simulation of human reasoning. The computer has determined profound transformations in many sectors of work, study and research. Among these, it is extremely relevant how the computer has completely transformed medicine and the medical role, especially in the field of radiology. Expert systems are the most interesting and futuristic applications of artificial intelligence. These systems are able to reproduce on a computer the behavior of an expert human being. Some of the recent innovations introduced in the field of breast, thoracic and mainly neural pathology are illustrated.