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A Chiesa

Publications and source records attributed to A Chiesa.

At least 37 records · Page 2Linked to original sources
PubMed1998

Congenital adrenal hyperplasia and early newborn screening: 17 alpha-hydroxyprogesterone (17 alpha-OHP) during the first days of life.

OBJECTIVE: Definition of upper limits for 17 alpha-hydroxyprogesterone (17 alpha-OHP) is important as its measurement is used in screening for congenital adrenal hyperplasia. This study aimed at investigating the cut off concentrations in relation to the day of sample collection. METHODS: 17 alpha-OHP concentration was determined in dried filter paper blood spots taken from cord blood and by heel pricking up to the sixth day of life. A sensitive fluoroimmunoassay (DELFIA) method was used. Samples from 1091 apparently health full term neonates were tested. Samples were separated according to the age of sampling. RESULTS: The 17 alpha-OHP (nmol/l blood) (median and 97.5th centile) concentrations according to the age of sampling were: cord blood (n = 126) 123.7, 265.6; first day 0-6 hours (n = 30) 49.4, 80.3; 6-12 hours (n = 57) 42.7, 79.8; 12-18 hours (n = 58) 38.1, 62.7; 18-24 hours (n = 67) 28.8, 49.7; second day 24-36 hours (n = 51) 23.6, 43.3; 36-48 hours (n = 63) 19.9, 35.4; third day (n = 200) 10.6, 23.5; fourth day (n = 197) 8.8, 20.8; fifth day (n = 76) 6.4, 18.3; sixth day (n = 166) 6.6, 19.4. CONCLUSION: Cord 17 alpha-OHP concentrations were very high as previously described, probably owing to steroid production by fetal adrenal glands. Therefore, cord blood is not useful for screening purposes. Thereafter there is a gradual decline in 17 alpha-OHP median concentrations. A cut off value of 30 nmol/l blood was useful in samples obtained after 48 hours of life. However, cut off values before 48 hours should be adjusted according to the sampling time.

Adrenal Hyperplasia, Congenital↗
PubMed1998

Nocturnal TSH surge and TRH test response in the evaluation of thyroid axis in hypothalamic pituitary disorders in childhood.

We studied, by means of TSH nocturnal secretion and TRH test, 42 children (4.2-19.9 years) with hypothalamic pituitary disorders and 24 healthy euthyroid children (5.7-15.4 years) as control group. Patients were divided according to their serum values of FT4 in group 1 (n = 27) with FT4 >/=10.3 pmol/l and group 2 (n = 15) with FT4 <10.3 pmol/l. TSH was measured by immunoradiometric assay. TSH nadir, TSH peak and TSH surge were calculated. Both groups differed significantly from control group in TSH surge values: group 1 (p < 0. 05), group 2 (p < 0.01). TRH test was abnormal in 11/27 patients of group 1 and 10/15 patients of group 2. In group 1, 7 patients had normal tests, 2 had abnormalities in both tests, 9 had only TSH nocturnal surge altered and 9 showed only TRH alterations. All patients of group 2 presented thyroid axis abnormalities. In conclusion, in patients with hypothalamic pituitary disorders with low FT4, no further investigation is required to demonstrate thyroid axis alterations, however in patients with normal FT4, nocturnal TSH secretion and TRH test may be required to evidence thyroid abnormalities.

Adolescent↗
PubMed1997

Principles of the surgical approach in human liver cystic echinococcosis.

Ultrasonography (USG) has recently contributed much to the diagnostic of hepatic cystic echinococcosis (CE). The use of portable ultrasonograph allowed us to perform a community survey among 9482 people living in a high risk area for CE in the Florida Department (Uruguay). Positive USG results were found in 123 asymptomatic patients. 48 out of 51 USG positive cases were surgically confirmed and 3 were found to be false positive. The results of this survey allowed us to propose a new classification of the echographic imaging based on the parasite's various evolutive and involutive stages. The Echinococcus granulosus cyst size was compared with the parasite's evolutive stages. The cyst's segmentary topography and the related risk of CE is evaluated. The importance of cystic-biliary communication is pointed out and its rational surgical treatment described. Finally, an algorithm is presented facilitating the choice of a rational treatment.

Adolescent↗
PubMed1997

CT appearance of the larynx after conservative and radical surgery for carcinomas.

The purpose of this study was to evaluate the normal CT appearance of the larynx after conservative and radical surgery. Postoperative (conservative surgery n = 52, radical surgery n = 21) CT examinations of 73 patients suspected of local/regional recurrence (n = 53) or asymptomatic (n = 20) were retrospectively analysed. The CT findings of 45 patients negative at biopsy were utilised to assess the normal appearance after surgery. Changes in the laryngeal framework represented constant landmarks, whereas the variety of soft tissues resection often resulted in a more unpredictable appearance of the neolarynx. Considerable thickening of the mucosa covering the arytenoid cartilage(s) has been detected after horizontal supraglottic laryngectomy (40 %) or supracricoid laryngectomies (SL; 100 %). A "pseudocord" due to scar tissue appeared to be a constant finding following vertical haemilaryngectomy, frequently after SL. Dilation of a lateral recess of the hypopharynx was observed after SL. This "pharyngeal pouch" had considerable size and air or liquid content. The most frequent CT findings among 28 tumours recurrent after conservative or total surgery were a mass larger than 10 mm spreading beyond the larynx (63.1 %), thickening of anterior commissure (57.9 %), erosion of residual cartilages (16.9 %). Although CT detected one subclinical recurrence, its employment is justified only to assess the submucosal extent of the lesion. This requires a thorough knowledge of normal postoperative findings.

Humans↗
PubMed1997

MR of malignant nasosinusal neoplasms. Frequently asked questions.

This paper focuses on the role of MR imaging of malignant neoplasms through a particular layout that emphasizes: (a) the rationale for the application of imaging; (b) the factors influencing the selection of sequences, planes and their proper arrangement; (c) the correlation between MR findings, imaging staging and clinical decision making. Since in most cases surgery is the treatment of choice, the precise assessment of the local extent and spread of tumour plays a key role in planning the surgical approach and influences either the therapy and the prognosis. However, the degree of spatial/anatomical detail required in treatment planning significantly differs between surgery and radiotherapy. Planning of the examination technique focuses on: (a) assembling sequences and planes in the shortest time possible; (b) the solution of specific problems: distinction between neoplasm and retained secretions within nasosinusal cavities; staging of submucosal spread toward the anterior cranial fossa, the orbit, the pterygo-palatine and superior orbital fissures. Since the most effective barrier to spread of neoplasms beyond sinusal walls does not depend on the mineral content of bone, but on the periosteum, assessment of the integrity of periorbita or dura mater is an essential information. Although MR cannot detect focal erosions of the thin sinusal walls, it reliably demonstrates both residual barriers (periorbita and dura), even though the bone has been completely destroyed. However, the final decision concerning orbital exenteration is made according to intraoperative staging. MR imaging can accurately precise the degree of anterior cranial fossa involvement. Furthermore, since either MR and CT accurately indicate the need to perform an anterior craniofacial resection and adequately exclude neoplastic invasion requiring orbital exenteration, more comparative studies are required to demonstrate that MR preoperative staging of nasosinusal malignancies is cost-effective.

Adenocarcinoma↗
PubMed1997

Relationship between asbestos bodies in sputum and the number of specimens.

OBJECTIVES: This study investigated the relationship between asbestos body identification and the number of sputum specimens obtained from each subject. METHODS: The presence of asbestos bodies in sputum was studied in 142 asbestos workers with former low-exposure levels; the number of specimens collected during 1-3 weeks varied from 2 to more than 4. Furthermore the persistence of asbestos bodies in the sputum of 15 asbestos workers was studied during a long-time follow-up. RESULTS: Asbestos bodies were present in at least 1 specimen in 44.4% of the 142 subjects. The cumulative percentage of asbestos body presence increased linearly, from 20% to 68%, as the number of specimens increased. CONCLUSIONS: Five specimens did not seem to be sufficient to obtain satisfactory sensitivity in a group with low exposure to asbestos. Neither the type of exposure (to chrysotile only or to chrysotile plus amphibole) nor the presence of an asbestos-related disease clearly influenced the probability of finding asbestos bodies.

Asbestos↗
PubMed1997

Three-dimensional MR myelography of traumatic injuries of the brachial plexus.

PURPOSE: To determine the diagnostic accuracy of three-dimensional MR myelography in the evaluation of traumatic injuries of the brachial plexus. METHODS: Twenty patients with clinical and electromyographic evidence of traumatic brachial plexopathy were examined with three-dimensional MR myelography, conventional cervical myelography, and CT myelography 1 to 9 months after trauma. Three-dimensional MR myelography was performed on a 1.5-T MR unit with a constructive interference in steady state (CISS) technique. For each patient, maximum intensity myelographic projections and multiplanar reconstruction reformatted 1-mm axial sections were obtained from the same 3-D data set. Three-dimensional MR myelographic findings were compared with findings at cervical myelography and CT myelography. Surgical findings were available for comparison in 13 patients. RESULTS: Three-dimensional MR myelography enabled detection of meningoceles with avulsed or intact nerve roots, partial or complete radicular avulsions without disruption of the thecal sac, dural sleeve abnormalities, and dural scars. Assuming cervical myelography and CT myelography as the standards of reference, 3-D MR myelography showed 89% sensitivity, 95% specificity, and 92% diagnostic accuracy in the evaluation of nerve root integrity. CONCLUSION: Three-dimensional MR myelography can show the majority of traumatic lesions that involve the proximal portion of the brachial plexus in a single rapid examination. On the basis of our findings, we propose this technique as a screening examination for patients with traumatic brachial plexus palsy.

Adolescent↗
PubMed1997

[Imaging of laryngotracheal stenoses in early and stabilized phases].

The contribution of new imaging modalities in the evaluation of laryngo-tracheal stenoses has been growing in recent years. This is due of the possibility of better investigate lesions which are difficult to assess by physical evaluation and of better identify the spread to the deep structures of malignant lesions. Congenital lesions require a chest x-ray as a first step examination, followed by an MRI study or a spiral CT study in order to identify vascular anomalies or mediastinal masses. Inflammatory stenoses are usually investigated by CT, while MRI seldom adds new data to those demonstrated by CT. The latter is mandatory in all traumatic stenoses because it allows an easy identification of fractures or dislocation of cartilages and hyoid bone. Scarring stenoses due to intubation or tracheotomy are also investigated by CT. CT or MRI are essential for the study of neoplastic stenoses. In these patients an ultrasound study and is also recommended permits the identification of abnormal lymphnodes and their US-guided fine needle aspiration. Stenoses due to compression originating from external structures require conventional studies of chest, trachea and esophagus. In these patients the differential diagnosis is reached by means of US, CT or MRI, according to the information provided by conventional studies. Finally, spiral CT is considered the most valuable tool to investigate and to plan the treatment in all the lesions which can undergo endoscopic therapy.

Endoscopy↗
PubMed1996

[Magnetic resonance and computed tomography compared in the staging of rhinosinusal neoplasms. A cost-effectiveness evaluation].

This study was aimed at comparing CT and MRI in the preoperative staging of sinonasal malignancies and at developing the most cost-effective diagnostic strategy to determinate resectability and choice of surgery and to assess surgical demolition extent. Forty-nine patients with sinonasal tumors were examined during a 10 years' period, with CT (20 patients), MRI (13 patients) and combined CT and MRI (16 patients); 42/49 patients underwent surgical resection (16 patients with craniofacial resection and 6 with orbital exenteration). Cost-effectiveness of the two techniques was assessed comparing five protocols using CT and MRI either alone or combined. In 40/98 orbits the tumor was in contact with a bone wall. MRI was more accurate than CT in assessing orbital invasion (100% sensitivity, 94% specificity, 86% positive predictive value and 100% negative predictive value, vs. 50%, 93%, 75% and 82%, respectively, for CT). MRI showed the tumor in contact with the skull base in 24/49 patients and CT in 23/49 patients, with no statistically significant difference between the two techniques. Dural infiltration, however, was better demonstrated with MRI in 3 patients with minimal bone erosion of the nasal vault. In 5 patients CT and MRI showed pterygopalatine fossa invasion (4 true positives and 1 false positive for both techniques). Since the final decision about orbital exenteration needs accurate surgical mapping, CT appears to yield all the pieces of information necessary for surgical planning. The most cost-effective protocol seems to be a CT examination for all patients. MRI is needed only for better prognostic assessment in the patients with minimal bone erosion of the floor of anterior cranial fossa. In fact, dural invasion, which is a markedly negative factor for survival, may be missed by CT.

Adolescent↗
PubMed1996

[Computerized tomography in the surgical planning of supraglottic carcinoma: analysis of cost-effectiveness in 69 patients].

This study was aimed at investigating the role of CT in the surgical planning (partial vs. total laryngectomy) of supraglottic laryngeal carcinoma. Sixty-nine patients affected with supraglottic cancers were reviewed to assess the accuracy and the clinical role of CT and laryngoscopy. The detection rates of tumor spread to the glottis, to thyroid and arytenoid cartilages, pyriform sinus and base of the tongue were compared and correlated with surgical and pathologic data. Thirty-one patients underwent supraglottic laryngectomy and 38 had total laryngectomy. Endoscopy correctly assessed the glottis in 54/69 patients (78.2%) and CT in 52/69 (75.3%). The two techniques were in agreement in 47/69 patients: 42/47 (89.4%) had a correct diagnosis. Sensitivity, specificity, accuracy, positive and negative predictive values in assessing neoplastic invasion at the glottic level were, respectively, 68.4%, 90.3%, 78.2%, 89.6%, 94.1% and 86.6% when endoscopy and CT were in agreement. In deciding the feasibility of supraglottic laryngectomy, the results of endoscopy alone did not differ significantly from those of CT and endoscopy in agreement (X2 = 3.255, p > 0.05), whereas the negative predictive value of CT was significantly lower than that of the two techniques in agreement (X2 = 4.55, 0.05 > p > 0.025). In our experience, CT did not significantly change the surgical treatment planned on the basis of endoscopic findings. Therefore, when assessing the feasibility of partial laryngectomy for supraglottic carcinoma, CT cannot be considered a cost-effective tool. Nine of 33 (27.2%) patients treated with total laryngectomy had local recurrences at the hypopharynx, probably because the primary tumor was underestimated at both preoperative staging and during surgery.

Carcinoma, Squamous Cell↗
PubMed1994

[Subarachnoid hemorrhage: assessment in the acute phase with angiography, with high-resolution magnetic resonance (angio-MR)].

Previous reports demonstrated that Magnetic Resonance Angiography (MRA) is a reliable means of diagnosing intracerebral aneurysms. However, in these early studies MRA was performed in patients with cerebral aneurysms already proved by intraarterial angiography. Our study was aimed at investigating the clinical feasibility and the diagnostic accuracy of high-resolution MRA in patients with acute subarachnoid hemorrhage. Twenty-five patients (15 women, 10 men) with CT diagnosis of subarachnoid hemorrhage were prospectively examined with high-resolution MRA within 24 hours of bleeding. All patients underwent intraarterial digital subtraction angiography (IA DSA) immediately after MRA examination. MRA studies were performed with a 1.5-T unit. MRA examinations of the cerebral vessels consisted of axial excitation of two 50-mm volume slabs, with 25% overlap, covering the cerebral circulation from the vertebro-basilar junction to the pericallosal artery. Pulse sequence variables were optimized to reduce voxel size (0.62 x 0.62 x 0.78) and to increase spatial resolution (160-mm FOV, 256 x 256 matrix, 0.78-mm slice thickness) while keeping S/N ratio high. The maximum intensity projection (MIP) reconstruction algorithm was used. The examination lasted nearly 20 minutes. Four MRA examinations (16%) were considered inadequate for diagnosis because of motion artifacts. High-resolution MRA detected 20 of 21 aneurysms in 17 patients, with 1 false positive and 1 false negative. Two patients had multiple aneurysms, 2 and 4 respectively, all of them detected by MRA. No cause of subarachnoid hemorrhage was found by IA DSA in 4 patients, while MRA studies were considered negative in 3 patients. Nineteen aneurysms were surgically clipped, while 2 basilar artery aneurysms were occluded by intravascular treatment. MRA and DSA findings were compared with surgical findings. Relative to IA DSA, MRA exhibited 95% sensitivity and 95% specificity. Aneurysm size ranged 2-10 mm: the smallest aneurysm detected by MRA was 2.5 mm. Anatomical and morphological agreement between MRA and IA DSA was excellent, with only slight MRA underestimation of the aneurysm size in 25% of cases and overestimation in 15% of cases. The aneurysm neck was shown by MRA in 60% and by IA DSA in 81% of cases. High-resolution MRA proved to be especially useful in complex anatomical sites where the direction of the aneurysm could be clearly demonstrated through the accurate selection of the appropriate projection angle and the careful examination of direct axial images.(ABSTRACT TRUNCATED AT 400 WORDS)

Acute Disease↗
PubMed1993

Ischaemic pontomedullary transection with incomplete locked-in syndrome. A case report with MRI.

We describe a case of incomplete locked-in syndrome (LIS) due to basilar artery thrombosis, in which MRI showed a complete, sharply demarcated infarct at the pontomedullary junction. This supports experimental data showing that the lower reticular formation is not critical for the maintenance of consciousness. To our knowledge, this is the first reported case of ischaemic pontomedullary transection with LIS.

Brain Ischemia↗
PubMed1993

The prediction of recommended energy expenditure for an 8 h work-day using an air-purifying respirator.

Thirty railway workers executed maximal, or near maximal, stress tests with and without the use of a half mask air-purifying respirator (Spasciani 85 A1 P1) fitted with two combined filters for simultaneous protection from organic vapours and particulate matter. The pressure-flow characteristics of inspiratory and expiratory resistance at airflows in the range 0-90 l.min-1 were established by a continuous flow method on one test mask. Significant differences were found by paired t-test between the two exercises (with and without use of mask), showing reduced values with use of the mask, for breath frequency, ventilation rate, oxygen uptake, carbon dioxide production, maximal oxygen uptake, percentage of maximal voluntary ventilation used at the maximal exercise ventilation. No significant differences were found for tidal volume, respiratory quotient, heart rate, systolic blood pressure, oxygen uptake at anaerobic threshold, and duration of exercise. The predicted energy expenditure recommended for an 8 h work shift, corresponding to 40% of maximal oxygen uptake, is found to be reduced working with respirator and is significantly different from that observed during stress test without mask. The average ventilation rate at this workload is below 25 l.min-1, with predicted inspiratory mouth pressure equal to, or less than, 20 mm H2O. This maximal inspiratory mouth pressure is proposed as a safety limit for prolonged work using a respirator, with a recommended energy expenditure close to 40% of maximal oxygen uptake.

Adult↗
PubMed1993

Specificity and sensitivity of 3rd generation EIA for detection of HCV antibodies among intravenous drug-users.

Serum samples from 487 ambulatory I.V. drug users were screened for HIV and HCV antibodies to determine the prevalence of coinfection in this high risk group for AIDS. For anti-HCV antibody screening we first used a 3rd generation EIA using, as antigen synthetic peptides which were not subjected to false positive results due to antibodies against superoxide dismutase or against yeast proteins (which may copurify with the recombinant proteins employed in the first and second generation test). The specimens that were positive in the screening test were confirmed by a more specific EIA system that detect antibodies to proteins encoded by structural (HCV-st EIA) and non structural (HCV-nst-EIA) regions of the HCV genome. A second confirmation assay was also performed: sera were run in presence or absence of blocking reagents which inhibits antibodies to C200 and C22 HCV epitopes for binding to the solid phase. The sensitivity of the HCV EIA screening for human HCV antibody detection revealed a 100% positivity for HCV infection. The confirmatory strategy presented in this paper revealed an HCV EIA specificity of 98.6%. In this work we demonstrated a significantly higher prevalence (p < 0.001) of HCV exposure in HIV infected individuals compared to the general population. Our experimental data also confirmed that HBV infection in drug-users at high risk for HIV infection was significantly associated with HCV infection (p < 0.001). In contrast, the acquisition of HIV by sexual contact was not a statistically significant risk factor for HCV coinfection.

False Positive Reactions↗
PubMed1993

[Comparison of ultrasonography, computerized tomography, and magnetic resonance in the study of parotid masses].

One hundred and seven patients were examined to compare advantages and pitfalls of the imaging methods currently used to stage parotid masses. Thirty patients underwent US and CT, 44 were investigated with US and MRI and 33 with US, CT and MRI. The accuracy of the three techniques was analyzed in detecting and assessing the intra-/extraglandular location of the parotid lesions and their benign/malignant nature. The intraglandular lesion spread to superficial/deep lobes was also investigated, together with its relationship to the surrounding structures. The findings were correlated with the cytohistological data from US-guided biopsy or from surgical resection. US was less accurate than CT and MRI, the latter being not statistically superior to the former. Because of the low incidence of pitfalls, US with fine-needle aspiration cytology should be the technique of choice; CT and MRI must be used for lesions > 3 cm or for masses in the deep gland lobes. In conclusion, CT accurately assesses parotid lesions but MRI demonstrates the relationship to adjacent structures better.

Adolescent↗