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D Caramella

Publications and source records attributed to D Caramella.

At least 19 recordsLinked to original sources
PubMed2006

IERAPSI project: simulation of a canal wall-up mastoidectomy.

Among the various EU research projects concerning the medical application of virtual reality, the project Ist-1999-12175, called IERAPSI (Integrated Environment for the Rehearsal and Planning of Surgical Interventions), specifically addressed the creation of a virtual and interactive surgical field for the temporal bone using three-dimensional images derived from CT data. We report on the experience obtained in the IERAPSI project in simulating a canal wall-up mastoidectomy. A surgeon with extensive experience in surgery of the petrous bone performed the mastoidectomy. The operative field included the mastoid, with its substantial differences in density between the cortex and the pneumatized bone, together with soft tissue structures, both on the border and inside the bone. The simulation is better in the first part of the operation than in the second part, suffering from a lack of haptic feedback from soft tissue and the surgical tool in deeper contexts, and under-representation of the variability inherent in pneumatized bone. This said, the excellent representation of dust production and removal, 3D simulation through color, and very good visual and haptic feedback in the early stage of the procedure are impressive. IERAPSI represents a potential surgical planning theater for the training of students and young surgeons, but is also expected to aid expert surgeons in the preoperative planning of difficult cases.

Computer Simulation↗
PubMed2005

Efficacy and safety of 48 weeks of treatment with octreotide LAR in newly diagnosed acromegalic patients with macroadenomas: an open-label, multicenter, non-comparative study.

The aim of the present multicentric, open-label, non-comparative study was to evaluate the role of octreotide long-acting repeatable (LAR) as primary therapy for the treatment of GH-secreting pituitary macroadenomas. The patients received octreotide LAR 20 mg every 4 weeks for 12 weeks; afterwards the dose was confirmed or adjusted at 30 mg every 4 weeks, for the remaining 12 weeks, for responder or non-responder patients, respectively. Responder patients continued the study until 48 weeks. Twenty-one naive active acromegalic patients were enrolled. In all patients, GH profile, IGF-I levels and magnetic resonance imaging (MRI) were evaluated at baseline and during treatment. The ability of octreotide LAR to decrease mean GH < 2.5 microg/I and/or normalize IGF-I levels, adjusted for age and gender, was defined respectively as total or partial success. Total success was achieved in 5/21 (23.8%), 6/20 (30%) and 4/14 (28.6%) patients after 12, 24 and 48 weeks; partial success in 7/21 (33.3%), 9/20 (45%) and 9/14 (64%) patients at 12, 24 and 48 weeks according to GH levels, while according to IGF-I levels in 7/21 (33.3%), 7/20 (35%) and 5/14 (35.7%) patients at 12, 24 and 48 week. Tumor size was notably decreased after treatment with octreotide LAR: in 16 macroadenoma patients completing the study, the tumor sizes were 1609 +/- 1288, 818 +/- 616 (49.1 +/- 23.7%) and 688 +/- 567 mm3 (54.6 +/- 24.4%) at baseline, 24 and 48 weeks. This study shows that octreotide LAR is effective in suppressing GH/IGF-I secretion and inducing tumor shrinkage in GH-secreting macroadenomas in a 48-week treatment. Octreotide LAR could be used as primary therapy in patients harbouring large pituitary tumors, who are less likely to be cured by neurosurgery.

Acromegaly↗
PubMed2005

Unique association of non-functioning pheochromocytoma, ganglioneuroma, adrenal cortical adenoma, hepatic and vertebral hemangiomas in a patient with a new intronic variant in the VHL gene.

We analyzed the clinical, hormonal, immunohistochemical and genetic features in a 69-yr-old Caucasian woman with a very rare "composite and mixed pheochromocytoma". This was characterized by right adrenal pheochromocytoma associated with homolateral ganglioneuroma and controlateral adrenal cortical adenoma. The three tumors, incidentally discovered, proved to be non-functioning (normal secretion of catecholamines and of other neuroendocrine peptides, glucocorticoids, mineralcorticoids and androgens). Accordingly, the patient showed no sign or symptom of endocrine disease. Computed tomography (CT) and magnetic resonance (MR) demonstrated a typical adenomatous lesion on the left adrenal gland with precocious uptake of the radiotracer on radioidine (131I)-norcholesterol adrenal scintigraphy, while the controlateral gland showed hyperdensity on CT, hyperintensity on MR and no uptake at adrenal scintigraphy. In addition, CT and MR revealed a vertebral and two hepatic hemangiomas. The right adrenal gland was surgically removed and, microscopically, pheochromocytoma and ganglioneuroma areas appeared intermixed without a predominant component. The former showed strong immunoreactivity for chromogranin, synaptophysin, vascular endothelial growth factor (VEGF) and CD34, while the latter appeared positive for neuron-specific enolase (NSE) and S-100. Peripheral blood genomic DNA analysis revealed a new intronic variant (5557A > G) in the von Hippel-Lindau gene (VHL) not observed in our control population.

Adrenal Cortex Neoplasms↗
PubMed2004

"Cyst-like" structures within the ciliary shafts in children with bronchiectasis.

"Cyst-like" structures within the ciliary shafts were considered in four adults as a primary defect involved in the development of bronchiectasis. In this study, the presence and the primary or secondary nature of this abnormality were assessed in children with bronchiectasis. High resolution computed tomography (HRCT) and nasal biopsies for motion analysis and transmission electron microscopy (TEM) evaluation of cilia were obtained in 45 children with recurrent lower airway infections and abnormal chest radiography. HRCT disclosed bronchiectasis in 35 out of 45 (77.8%) children and cyst-like structures were demonstrated with TEM in 29 out of 45 (64.4%) patients. Cyst-like structures were constantly associated with other ultrastructural abnormalities commonly observed in chronic inflammation, and were found both in subjects with primary and with secondary ciliary dyskinesia. When considering only patients with bronchiectasis, a significant correlation between prevalence of cyst-like structures and the severity of bronchiectasis was demonstrated. Follow-up (2-22 months) of seven patients demonstrated that in the five children with secondary dyskinesia, the ultrastructural defect completely disappeared and there was a small reduction in the abnormality in the two patients with primary dyskinesia. In contrast to one previous report, the reversibility of the defect suggests its secondary origin, which is most likely related to chronic airway inflammation.

Adolescent↗
PubMed2002

A computer science approach to managing security in health care.

The security of electronic medical information is very important for health care organisations, which have to ensure confidentiality, integrity and availability of the information provided. This paper will briefly outline the legal measures adopted by the European Community, Italy and the United States to regulate the use and disclosure of medical records. It will then go on to highlight how information technology can help to address these issues with special reference to the management of organisation policies. To this end, we will present a modelling example for the security policy of a radiological department.

Computer Security↗
PubMed2001

Renal artery stenting in patients with a solitary functioning kidney.

PURPOSE: To retrospectively evaluate the results of renal artery stenting in patients with renovascular disease and a solitary functioning kidney. METHODS: Palmaz stents were placed in 16 patients with a solitary functioning kidney, renal artery stenosis, hypertension and renal failure. Stenoses were evaluated with color Doppler ultrasound, MR angiography and digital subtraction angiography (DSA). Indications for stenting were: recoil after percutaneous transluminal renal angioplasty (PTRA) (63%), arterial dissection after PTRA (13%) and primary stenting (25%). Immediate results were evaluated by DSA. On follow-up (6-36 months), patients underwent periodical evaluation of clinical conditions (blood pressure and serum creatinine level) and stent patency, by means of color Doppler ultrasound. RESULTS: Stent placement was successful in all patients (100%). Cumulative primary patency rate was: 100% at 1 day, 93.75% at 6 months, 81.25% at 12 months and 75% at 24 months. A significant reduction in diastolic blood pressure occurred (mean +/- SD 104 +/- 6 vs 92 +/- 3; p < 0.05); renal function improved or stabilized in over 80% of patients. However, there was no significant difference in the creatinine values before and after treatment (mean +/- SD 200 +/- 142 micromol/l vs 197 +/- 182 micromol/l; p > 0.05). CONCLUSION: Renal artery stenting, both after PTRA and as primary stenting, represents a safe procedure, able to preserve renal function in patients with a solitary functioning kidney.

Adult↗
PubMed2001

Eosinophil cationic protein in infants with respiratory syncytial virus bronchiolitis: predictive value for subsequent development of persistent wheezing.

Infants with acute bronchiolitis during the first months of life are at increased risk of developing persistent wheezing and bronchial asthma later in life. The study of eosinophil cationic protein (ECP) suggests that eosinophil-related inflammatory mechanisms may play a role in respiratory syncytial virus (RSV) bronchiolitis. The aim of our study was to verify whether serum ECP (s-ECP) measurements are useful in predicting the development of persistent wheezing in children affected by RSV bronchiolitis during a 5 years follow-up period. Forty-eight infants were enrolled prospectively (mean age: 153.5 days). All had a clinical and radiological diagnosis of acute bronchiolitis and confirmed RSV infection. Peripheral eosinophil counts, levels of s-ECP, and serum IgE concentrations were measured during bronchiolitis. Five years later the children were re-evaluated in regard to their respiratory symptoms (standardized questionnaires) and atopic status (specific IgE levels). We observed significantly higher s-ECP levels (P < 0.001) at enrollment in subjects who developed persistent wheezing compared to subjects who did not show late wheezing. Initial s-ECP values allowed significant and correct prediction of persistent wheezing (P < 0.001). The risk to develop respiratory symptoms was 9.73 higher for infants with s-ECP levels > or = 8 microg/L than for those with s-ECP levels <8 microg/L (P < 0.0001). In conclusion, our study suggests that s-ECP levels in infants with bronchiolitis are useful in predicting the risk to develop wheezing in the subsequent 5 years.

Asthma↗
PubMed2001

Virtual endoscopy of the middle ear.

Virtual endoscopy is a computer-generated simulation of fiberoptic endoscopy, and its application to the study of the middle ear has been recently proposed. The need to represent the middle ear anatomy by means of virtual endoscopy arose from the increased interest of otolarygologists in transtympanic endoscopy. In fact, this imaging method allows the visualization of middle ear anatomy with high detail, but it is evasive and is essentially used for surgical guidance. Virtual endoscopy provides similar perspectives of the tympanic cavity but does not require the tympanic perforation. In the study of the middle ear, specific attention is given to the retroperitoneum. This region contains elevations of the medial wall (pyramidal eminence and ridge, styloid eminence and ridge, subiculum, ponticulus) and depressions (sinus tympani, posterior sinus tympani, facial sinus, fossula of Grivot, oval window fossula), which can be effectively displayed by virtual endoscopy. Virtual endoscopy is foreseen as a useful tool in preoperative management of patients who are candidates for middle ear surgery, since it can predict with high detail the patient's specific anatomy by imaging perspectives familiar to otosurgeons.

Computer Simulation↗
PubMed2000

Real-time volume rendering of MRCP: clinical applications.

MR-cholangiopancreatography (Signa Contour 0.5T; GE/Medical Systems, Milwaukee, WI) data sets of 156 patients, obtained with a 2D T2-weighted FSE sequence, in the coronal plane, were volume rendered (Advantage Windows 3.1; GEMS) independently by two radiologists, that were asked to define the range of signal intensities in which the signal of the pancreaticobiliary system was included and to rank the quality of native images and volume renderings. Patients had biliary stones (n = 47), inflammatory ampullary stenoses (n = 18), pancreatic tumors (n = 12), surgical bilio-enteric anastomoses (n = 19), ampullary carcinomas (n = 2), pancreatic duct stone (n = 1), cholangiocarcinoma (n = 3) and normal pancreaticobiliary tree (n = 54). Good quality volume renderings of the bile ducts were obtained for at least a maximum diameter of 1.5 mm. The quality rank agreement between volume rendering and native images was excellent (k = 0.94). The correlation between the observers for the setting the signal intensity range was excellent and statistically significant (P < 0.001). The correlation between the observers for the time of volume rendering was not statistically significant. Biliary stones could be displayed in 32/47 (68%) cases. The pancreatic duct stones was displayed as well. Inflammatory ampullary stenoses were detected in all cases (100%). In case of pancreatic tumors, cholangiocarcinomas and ampullary carcinomas volume rendering allowed to identify the site of stenosis. In surgical bilio-enteric anastomoses volume rendering was helpful to display the residual biliary tract, the site of anastomosis and the enteric tract. Volume rendering could be a reliable and efficient tool for the study of the anatomy and pathological changes of the pancreaticobiliary tract.

Adolescent↗
PubMed2000

[Researching and publishing on the Internet].

The popularity of Internet is rapidly growing in all fields, and Radiology is no exception. Thousands of websites with radiological data have been enthusiastically created and are now available on-line, competing with the huge number of sites offering any kind of information or commercial services. After the pioneering experiences of the early Internet years, now time has come to critically analyze the opportunities and the risks of using Internet as a channel for distributing radiological knowledge.

Computer Communication Networks↗
PubMed2000

CT-guided radiolabelled aerosol studies for assessing pulmonary impairment in children with bronchiectasis.

OBJECTIVE: To determine whether CT-guided mucociliary clearance studies allow differentiation between bronchiectasis associated with primary ciliary dyskinesia (PCD) and those unrelated to congenital or genetically transmitted defects. MATERIALS AND METHODS: Fifteen children aged 4-18 years with a CT diagnosis of bronchiectasis were included in the study. Six had PCD, while in nine cases no congenital disorder was demonstrated. RESULTS: CT showed bronchiectasis in 26 (29%) of 90 lung regions. Radiolabelled aerosol studies were conducted globally for each lung and on the regions affected by bronchiectasis. Global half-time of activity (t 1/2) values of patients with PCD were significantly higher (P < 0.001) than those with bronchiectasis unrelated to congenital disorders. Among the 26 lung regions in which CT demonstrated bronchiectasis, regional clearance was abnormal in 24 cases. Patients with PCD showed no statistically significant difference between regional and global t 1/2 values. Patients with bronchiectasis unrelated to congenital disorders showed significantly higher regional t 1/2 values in the affected regions with respect to the corresponding global pulmonary t 1/2 (P < 0.06). CONCLUSIONS: The combination of morphological CT information with functional data concerning the clearance of radiolabelled aerosol adds to our understanding of pulmonary impairment in children with bronchiectasis. In particular, regional studies allow the recognition of different mucociliary clearance patterns in bronchiectasis associated with PCD and those unrelated to congenital or genetically transmitted defects.

Adolescent↗
PubMed2000

High-resolution magnetic resonance and volume rendering of the labyrinth.

Our aim was to verify the feasibility of volume rendering (VR) of high-resolution magnetic resonance (HR-MR) data sets of the labyrinth. We retrospectively reviewed the HR-MR data sets of 16 consecutive patients with no MR evidence of labyrinthine pathology. High-resolution MR data sets were obtained by means of a 3D T2-weighted FSE sequence with the use of a 3-in. circular surface coil for signal reception, and processed with a high-end workstation. Two reviewers performed separately VR of the labyrinth by selecting the signal intensity interval for attribution of opacity and transparency. Concerning the time taken for definition of the volume of interest, the two observers needed, respectively, 28.9 and 33.1 min (SD +/- 8.7-9.5 min), whereas the time taken for VR was respectively, 26 and 33.2 min (SD +/- 8.8-8.9 min). Concerning the selection of the signal intensity interval, the two observers had, respectively, 86.4 and 88.7 mean lower threshold (SD +/- 34.5-33.5), 488.9 and 495.4 mean upper threshold (SD +/- 56.3-53.8). In our experience, we have found VR of HR-MR to offer a reliable and reproducible technique for producing 3D representations of the labyrinth. The VR algorithms use all data within the imaging volume and optimize the dynamic range ascribed to the object being visualized.

Adolescent↗
PubMed2000

Teleradiology in Europe.

The new concept of teleradiology is centered on the consideration that it involves management of medical information rather than the simple transmission of diagnostic images from one location to another. Teleradiology must therefore be able to contribute to the seamless integration of the digital environment in which medical data are managed throughout and beyond the hospital, generating value added services for the patients as well as prospective economical benefits for the institution. In this perspective the evolution of telecommunication with the spectacular success of mobile telephony and Internet will play and increasingly important role, by allowing further development in the exchange of multimedia medical information on a regional as well as international level. However, new responsibilities are being given to the radiologists, who must take all necessary technical and organizational actions in order to avoid that the digital management of data may endanger the confidentiality and the integrity of patients' data.

Computer Security↗
PubMed2000

Contrast-enhanced color Doppler ultrasonography in suspected parathyroid lesions.

PURPOSE: To assess the usefulness of US contrast media in the evaluation of patients with primary hyperparathyroidism, with a nodule showing US features of a primary parathyroid lesion but lacking the color Doppler US appearance of a parathyroid mass. MATERIAL AND METHODS: Thirteen patients (7 female, 6 male; age range 51-79 years) were examined with US before and after administration of a stabilized galactose-based microbubble contrast agent. Ten patients underwent surgery and the final histological examination demonstrated parathyroid adenoma in 9 cases and a mesenchymal benign nodule in 1 case. Three nodules were proved to be of thyroid origin at fine-needle aspiration biopsy. RESULTS AND CONCLUSION: The use of a US contrast agent resulted in a diagnostic gain compared to unenhanced studies in 12/13 cases. Color Doppler findings characteristic of parathyroid lesions were observed in 7/13 cases, of thyroid nodules in 4/13 cases, and nonspecific patterns in 2/13 cases. Contrast-enhanced color Doppler US can be proposed in selected patients in whom unenhanced color Doppler provides uncertain findings. Its ideal application should be the evaluation of cervical lesions without detectable intranodular flow at unenhanced Doppler studies. In these cases, the contrast agent helps in visualizing typical color Doppler signals of the parathyroid lesions ("vascular pole" and "mixed pattern").

Adenoma↗
PubMed2000

MR virtual endoscopy of the upper urinary tract.

OBJECTIVE: We investigated the feasibility of applying surface-rendered virtual endoscopy to the visualization of the upper urinary tract by processing unenhanced MR urography data sets. SUBJECTS AND METHODS: Twenty-six patients, having neoplastic lesions (n = 9), calculi (n = 8), pelviureteric junction stenoses (n = 4), postoperative fibrotic strictures (n = 3), and extrinsic compressions of the ureter (n = 2), underwent unenhanced MR urography. Virtual endoscopy of the upper urinary tract was obtained using a thresholding technique and surface-rendering MR urography data sets. RESULTS: Virtual endoscopy of the renal pelvis and calices was feasible in all cases on the side of the urinary obstruction. Virtual endoscopy of the ureter was obtained for a diameter of at least larger than 5 mm. The nondilated side could be partially explored in 11 cases (43%). The mean virtual endoscopy threshold required for the visualization of the urinary tract was 157.36-159.94. The mean time for virtual endoscopy was 13.8 min. Endoluminal masses were found in three (12%) of 26 cases on the renal pelvis (corresponding to neoplastic lesions), and occlusions, in 23 (88%) of 26 on the pelviureteric junction and ureter (neoplastic lesions and other abnormalities). CONCLUSION: Virtual endoscopy of MR urography data sets is feasible in patients with urinary tract dilatation. Virtual endoscopy displays the renal pelvis, calices, and ureter and, moreover, can show endoluminal changes caused by abnormalities.

Diagnostic Techniques, Urological↗
PubMed2000

Virtual endoscopy of the middle and inner ear with spiral computed tomography.

OBJECTIVE: To evaluate the inner anatomy of the auditory apparatus by means of virtual endoscopy of spiral computed tomography (CT) data sets. BACKGROUND: Virtual endoscopy permits simulation of the fiberoptic endoscopy perspective by processing CT or magnetic resonance images. METHODS: Seven formalin-fixed specimens of human mastoid were scanned with spiral CT with the following protocol: beam collimation 1 mm, pitch ratio 1, reconstruction spacing 0.2 to 0.5 mm, field of view 90 mm. For the generation of endoscopic views of the auditory spaces, the axial images were processed with Navigator software 2.0 running on UltraSparc I workstation. RESULTS: Virtual endoscopy allowed the demonstration of the external auditory canal, the head and handle of the malleus, the stapes and incudostapedial articulation, the corpus, the long process of the incus with its lenticular process and the short limb, the malleoincudal articulation, the rounded promontory, the round and oval windows, and Prussak's space. From inside the basal turn of the cochlea, virtual endoscopy showed the orifices of the fenestrae cochlea and vestibuli, the origin of the lateral and the anterior semicircular canals, and the basal turn of cochlea. The optimal perspectives that allowed demonstration of the anatomical details of the middle and inner ear are described. CONCLUSION: Virtual endoscopy allows the generation of inner views of the auditory spaces. This new method of image processing can be proposed as an integrative tool of spiral CT imaging.

Culture Techniques↗