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A Morra

Publications and source records attributed to A Morra.

At least 19 recordsLinked to original sources
PubMed2002

Usefulness of virtual endoscopic three-dimensional reconstructions of the middle ear.

This work uses a new programme for producing 3D radiological images acquired by means of CT which enables the internal surfaces of the examined structures to be visualized. This new method, which is able to navigate inside organs in a similar way to fibreoptic endoscopy, is known as virtual endoscopy. CT examinations of the temporal bone were carried out using spiral equipment and endoscopic 3D processing was carried out on a separate workstation equipped with a volume-rendering programme. Once the technical parameters necessary for obtaining a representation of the internal surfaces had been defined, a simulation of a virtual otoscopy was conducted by moving the virtual endoscope from the external auditory canal through the annulus to the tympanic cavity. The simulation can be obtained either by moving the endoscope by hand, using the mouse, or by defining a path along which the software automatically creates an endoscopic 3D reconstruction. The images thus obtained are projected sequentially to give a "movie" effect, i.e. a continuous progression of the endoscope. The average time required to conduct the procedure ranges from 20 to 30 min. A virtual endoscopic visualization of the middle ear was obtained which, in particular, generated images of the tympanic cavity with the ossicular chain. In our experience, virtual otoscopy shows the anatomy of the structures of the tympanic cavity in excellent detail and may be considered complementary to CT, providing useful images enabling better visual representation and understanding of this complex structure. Although clinical applications of the technique remain to be defined it may have a role to play in presurgical diagnostic evaluation of the ossicular chain, epitympanum and retrotympanum.

Ear, Middle↗
PubMed2001

[Spiral-CT with multiplanar reconstructions (MPRS) in the evaluation of ureteral neoplasms: preliminary results].

PURPOSE: Urothelial tumors of the upper urinary tract (renal pelvis and ureters) are rare: the most common of these are Transitional Cell Carcinomas (TCC), usually localized in the bladder (75% of cases), whereas only 7-10% arise in the renal pelvis and 2,5-5% in the ureter. Multicentricity is not infrequent and synchronous or metachronous tumors have been reported to develop in 11-13% of patients with upper urinary tract cancer and 2-4% of those with bladder cancer. The presence of additional lesions can change patient management. Clinically these tumors may present with hematuria or flank pain, but sometimes there are no specific clinical findings. Radiological studies play an important role in tumor detection and staging and in follow up. The diagnosis is usually performed by IVU and US, while CT is generally employed in the staging. Our purpose was to verify the role of Spiral CT with Multiplanar Reconstructions (MPRs) in the evaluation of ureteral tumors. MATERIAL AND METHODS: Nine patients with ureteral neoplasms were examined with a single detector spiral-CT, using the following parameters: 120 kV, 200 mA; 5 mm collimation, pitch 1.4, slice reconstruction every 5 mm; image acquisition 2-5 minutes after injection of 120 cc of contrast medium (300 mgI/ml). All the exams were transferred to a separate workstation to obtain curvilinear MPRs. RESULTS: Spiral CT on the axial plane visualized 4 urothelial tumors as concentric ureteral wall thickening; 3 as intraluminal soft tissue masses, with involvement of almost the entire urinary tract, as far as the bladder in 1 case. In other 2 patients there were synchronous lesions which presented both patterns (wall thickening and intraluminal mass). In all cases the lesions exhibited moderate enhancement after c.m. injection. Medium- to high-grade hydronephrosis above the tumors was always present. On MPRs both ureteral involvement and dilated, urine-filled upper urinary tract were clearly represented on coronal and sagittal oblique planes; these images allowed to visualize the craniocaudal extension of short or long lesions, and to detect multicentricity. DISCUSSION: The radiological diagnosis of ureteral tumors is usually performed by IVU, US and CT. IVU allows to visualize the tumors as filling defects or irregular narrowing of the ureteral lumen. IVU however is unable to show the real extent of the tumor in obstructive disease or in nonfunctioning kidney. US visualizes the lesion as an echoic mass in the lumen, although it is sometimes difficult to differentiate neoplastic lesions from other filling defects and to visualize the entire ureteral tract. CT is generally employed in the staging of ureteral tumors. CT findings are usually very useful for distinguishing ureteral neoplasms from other filling defects based on their attenuation and enhancement characteristics. Spiral CT with MPRs allows to obtain panoramic views of the urinary tract; these images are more effective than those of IVU, because of their capability to show the longitudinal extension of the lesion and the presence of multicentric tumors. Furthermore with MPRs it is possible to visualize the ureteral tract distal to the lesion, overcoming the limitations of IVU in nonfunctioning kidney or obstructive disease. CONCLUSIONS: Spiral CT with MPRs is useful in the evaluation of ureteral tumors as it is capable of visualizing the whole extension of the lesion and the presence or absence of multicentric lesions, which can change patient management.

Aged↗
PubMed1999

[Colonoscopy with computed tomography with volume reconstruction. The results and a comparison with endoscopy and surgery].

PURPOSE: Virtual CT colonoscopy is a novel technique whose diagnostic accuracy and clinical yield are currently investigated. Several studies have shown its capabilities in detecting colon and rectal cancers. We report the results of a preliminary experience with the volume rendering technique and compare CT colonoscopy with endoscopy and surgery. MATERIAL AND METHODS: Our series consisted of 25 patients with colon cancer confirmed at endoscopy and/or surgery. All examinations were carried out with a spiral CT scanner Philips Tomoscan AVE1. Intestinal preparation was adequate in all patients, consisting in gas insufflated immediately before acquisition, after the injection of 100 mL iodinated contrast agent. All examination were performed in prone position using axial 5 mm slices with 5 mm table feed (pitch 1) and 2 mm reconstruction index; 120 kV and 200-250 mA were used. Images were transferred to a workstation (Easy Vision, Philips, release 4.2.1.1) for processing. We acquired multiplanar (MPR) and virtual endoscopic images with volume rendering; the selected threshold was -250 to -600 Hounsfield Units. Virtual endoscopic images could be obtained in 23 of 25 cases. The results of the radiological study were compared with endoscopic and surgical findings in 25 and 17 cases, respectively. RESULTS: Endoscopy and surgery detected 46 lesions: 29 were malignant and 17 benign. Axial CT and MPR alone detected 35 lesions (76%), 29 of them malignant and 6 benign. The 11 benign lesions missed by axial CT ranged 6-8 mm in diameter. There were no false positives. CT colonoscopy alone detected 66 lesions, but 22 of them were false positive due to residual stool in the colon (21 cases) and to residual barium in the colon (1 case). Combining CT colonoscopy and axial and MPR images enabled to correct the false positive diagnoses made by CT colonoscopy alone and to decrease the false negative ratio of axial and MPR images. Forty-one of 44 lesions (93%) were detected. Thirty-seven lesions were found in the 17 surgical patients; 34 of them were correctly identified combining CT colonoscopy and axial and MPR findings, while endoscopy detected only 31 lesions. Thus, CT had 92% sensitivity, versus 83% of fiberoptic endoscopy. CONCLUSION: In this preliminary experience volume rendering CT colonoscopy exhibited high sensitivity in detecting colon cancers, but their correct evaluation and characterization can be obtained if axial and MPR studies are combined. Further investigation and technological developments are necessary to define the yield of this new technique.

Adenocarcinoma↗
PubMed1998

Radiographic assessment of atrial dipole position in single pass lead VDD and DDD pacing. The Multicenter Study Group.

Atrial electrode position was determined by radiographic analysis in 160 patients paced in single-lead VDD for second- or third-degree A-V block, implanted > 1 year with Phymos single pass leads and Phymos 3D pacemakers. The packing lead features an atrial dipole with a 30-mm electrode interspace. In 44% of patients, the upper atrial electrode was positioned within a band of 20 mm centered at the level of the superior vena caval insertion (junctional area) and was in the inferior vena cava or in the atrium in 35% and 21% of cases, respectively. In spite of these different dipole locations, all patients had stable atrium-driven pacing at routine follow-up visits. With the electrode in the junctional area, unipolar stimulation of up to 5 V for 1 ms resulted in stable atrial capture in 63% and 59% of the patients in supine and upright positions, respectively. With the electrode in the atrium, corresponding success rates were 45% and 54%. In the atrium, however, the prevalence of diaphragmatic stimulation was significantly lower than at the junction (10% vs 42% in supine position; 21% vs 47% upright). Though atrial sensing function proved adequate in a wide range of positions, these results suggest that the Phymos lead atrial dipole should be positioned within the atrium, as close as possible to the atrial wall, to maximize the number of VDD patients who might benefit from single-lead DDD pacing.

Cardiac Pacing, Artificial↗
PubMed1997

[Virtual endoscopy with computed tomography of the anatomical structures of the middle ear].

INTRODUCTION: We applied the new technique of virtual endoscopy to the middle ear because this anatomical area is characterized by favorable contrast. MATERIALS AND METHODS: CT examinations of the petrous bone were obtained using 1.5 mm thick 1 coronal axis slices, with 1 mm or 1.5 mm table feed, 120 kV, 140-170 mA and 2 s scan time. The images were reconstructed with the high resolution algorithm for bony structures and a small field of view (9.6 cm), separately for the right and left petrous bone. The images were then transferred on a workstation and processed with the Navigator virtual endoscopic software (General Electric). A threshold value ranging -350 to -600 HU was applied. RESULTS: A series of images is acquired as the virtual endoscope moves from the external auditory canal to the middle ear cavity. Images of the anterior, medial, and posterior surfaces of the middle ear are presented. Different views of the ossicles are also presented. High quality images were always obtained for the middle ear structures, including the ossicles. CT endoscopy of the middle ear provides a new view of the anatomy of this complex area. It has some advantages and disadvantages; the former can be summarized as follows: -demonstration of areas which are difficult to show with endoscopy because of the presence of membrana tympani; -the virtual endoscope can be placed in several positions and therefore it can be inserted in all sites and tortuous places of anatomical cavity; -nice and effective demonstration of the ossicular chain including the stapes. The disadvantages are related to the fact that the endoscopic reconstruction (such as any other three-dimensional reconstruction) is a representation of surfaces where different densities are necessarily homogenized. CONCLUSIONS: CT virtual endoscopy of the middle ear can currently be considered a complementary technique to conventional CT because it permits better anatomical detailing of this complex region.

Ear, Middle↗
PubMed1996

Transvalvular impedance (TVI) recording under electrical and pharmocological cardiac stimulation.

The cardiac electric impedance was recorded between right atrium and ventricle, throughout the cardiac cycle, by means of a tripolar single pass lead for VDD pacing. The transvalvular impedance signal (TVI) is a sharp periodic wave, with high signal-to-noise ratio, that is detected exclusively in the presence of cardiac mechanical activity. The minimum TVI value is attained during the atrial systole, the maximum at the end of ventricular systole. Different parameters of TVI waveform are affected by changes in the inotropic state, and could therefore be proposed as potential signals for new rate responsive algorithms based on the correlation between inotropic and chronotropic regulation. The signal might be used, moreover, for pacing and sensing validation in autoregulating pacemakers and for fibrillation recognition in ICDs.

Adrenergic Agonists↗
PubMed1995

[Air crash simulation at the Torino-Caselle airport].

PURPOSE: The simulation purpose has consisted in apparising "the aid succour quality indicators". MATERIALS AND METHODS: Study of the succour chain during the air line hypothetical crash with 80 passengers on board, happened at 11:35 "H O". DESCRIPTION: The alarm reaches the control-tower at 11.36. The control-tower sends it out according to an internal protocol. At 12:30 (H + 55) the number 5747 operative station reported the simulation end. ANALYSIS RESULTS: Only the succour sanitary aspects are considered. There was not an adequate arrangement and co-ordination of the rescue-succour components. CONCLUSIONS: The truth is that the succours chain can be improved either in the organisation and in the operative capacity, even if is very difficult to weigh such inadequacy.

Accidents↗
PubMed1980

[Gestalt therapy of complaints].

People can express their suffering voicing it, complaining with their body, with gestures, movements; for alerts eyes it is even more comprehensive and true than words. Complaints that human beings are capable of expressing are not so many, there are only a handful, and this work intends to be exhaustive in its exposition. It is possible to complain against third persons. It is also possible to do so against oneself assuming either the intransigent attitude of a father who judges a son who does not fulfill his expectancies, or as a son who resents the paternal demands which he feels he cannot comply. Other kind of complaints include physical symptoms, either isolated (cephalea, dysnea, urticaria) or constituting syndromes or illnesses. Losses suffered are also a source of complaints, whatever the lost object might be (person, situation, material things or a part of oneself). It can be mourned because of its absence, or else by feeling guilty of the real or imaginary damage inflicted or else by feeling indisolubly linked to it with a phantom tie. Other types of complaints are the feeling of dependancy towards something oppressive, be it a substance, such as alcohol, smoking, drugs or overeating, or it may be a person or a situation. In view of the compulsive addiction characteristics with which the subject lives, it is possible to assimilate this dependancy and the feeling of oppression and damage to the link with a toxic.

Female↗
PubMed1979

[Facial telethermography in the diagnosis of carotid insufficiency in the extracranial sector].

The usefulness of facial telethermography in the diagnosis of circulatory insufficiency owing to occlusion of the extracranial vessels is discussed. The method has proved of great assistance in the screening of patients with vascular diseases, and in the choice of a subsequent contrastographic examination. It gave a significant number of positive findings in cases of insufficiency of the internal carotid artery. The number of false positives and false negatives was virtually negligible.

Arterial Occlusive Diseases↗