Biomedical subjects

P Bravetti

Publications and source records attributed to P Bravetti.

At least 19 recordsLinked to original sources

PubMed2006

Quantitative analysis of the elastic fibres in the human temporomandibular articular disc and its attachments.

A quantitative study of the elastic fibres found in the human temporomandibular disc and its attachments was performed. Seven left discs from 57- to 82-year-old subjects, without macroscopic evidence of a TMJ disorder, were analysed and prepared in parasagittal sections. The surface amount was measured, thresholded and expressed from 0 to 1, using microscopic digitized views after Weigert's resorcin-fuchsin staining of elastic fibres. Fibre density rates ranged from 0 to 0.687. The mean density was 0.1532 (sigma=0.1150) in the upper bilaminary zone, 0.1097 (sigma=0.1159) in the lower bilaminary zone, 0.0474 (sigma=0.0782) in the anterior band, 0.0180 (sigma=0.0603) in the posterior band and null in the intermediate zone. The difference in density rate between the structures was significant, except for the posterior band and the intermediate zone. The elastic fibre density rates in central and medial locations of the upper and lower bilaminary zones were twice as big as in the lateral locations. In the anterior band, the elastic fibre density was less abundant medially than in its lateral part. These quantitative results support the current elastic fibre distribution scheme, and confirm the necessity of studying their orientation, taking into account age and temporomandibular joint health parameters.

Age Factors↗

PubMed2006

Labiomandibular paresthesia caused by endodontic treatment: an anatomic and clinical study.

Labiomandibular paresthesia after root canal treatment is an accident that is still too frequent despite the development of new endodontic techniques. The aim of this anatomical and clinical study is to advance the understanding of how accidents occur so as to avoid them. This anatomical study made it possible to determine the variability of proximity of the apex of the tooth root to the mandibular bundle, as well as the relationship between the nerve and its satellite artery, and to understand how endodontic filling material spreads into the cancellous bone. The clinical study, which included examination with conventional radiology as well as with imaging techniques, enabled us to identify the exact location of the filling material in relation to the mandibular bundle and to correlate this to the occurrence of clinical symptoms and their diverse manifestations.

Cranial Nerve Injuries↗

PubMed2005

Functional anatomy of the human lateral pterygoid muscle.

The authors studied the lateral pterygoid muscle of 179 fresh cadavers by both anatomical dissection and magnetic resonance imaging. The aim was to define the general morphology and the architectural organisation of the lateral pterygoid muscle. Dissection plane by plane, anatomical sections in different planes of space and dissections via multiple approaches on harvested blocks allowed the demonstration that the lateral pterygoid shows an architectural arrangement different from that which is usually described but similar to that, from its typically penniform structure of the masseter and the medial pterygoid. The anatomical situation of this muscle gives rise to numerous differences in opinion much to its morphology as to its functional examination. This study has shown that one part of the muscle has a typical penniform structure made up of alternating musculo-aponeurotic layers and by the absence of individual muscle bellies. In addition the particular shape of this muscle makes it useless to insert intramuscular electrodes in its only accessible portion, which makes the results of electromyographic studies debatable.

Aged↗

PubMed2005

[Anticoagulants and dental extractions].

Dental extractions in patients under platelet antiaggregant or anticoagulant therapy pose the problem of risk benefit between stopping or carrying on treatment. The difficulties of reequilibrating the INR after a heparin relay have led surgeons and cardiologists to look for alternative solutions. Different means of local haemostasis using products with haemostatic properties or not, or the use of sutures or glues, have given encouraging results but there is too much uncertainty for systematic recommendations to practicians responsible for dental extractions in these patients. The authors propose a technique which has the advantages of associating systematically different methods, making bleeding complications very unusual, without interrupting anticoagulant or antiaggregant therapy.

Adult↗

PubMed2004

Histological study of the human temporo-mandibular joint and its surrounding muscles.

This is a histological study of the human temporo-mandibular joint and its surrounding muscles. Using a microscopic study of serial sections from anatomical specimens from six subjects, the detailed anatomy of the joint is presented with particular regard to the histology. This study has allowed, in particular, the description of the ligaments and capsule as well as the insertions of the masticatory muscles (temporalis, masseter, lateral pterygoid) on this joint. These observations are then compared with the anatomical and histological data already reported on this subject. This study shows that the bulk of the muscular fibres of the lateral pterygoid passes under the foot of the disc is attached over the whole height of the condylar, unite and extend as far as the medial pole of the joint under the insertion of the articular disc. An insertion of the temporo-masseter musculo-tendinous complex on the anterior and lateral capsulo-discal structures was observed. The lateral pterygoid is composed of a succession of tendinous and fleshy fibres. This study confirms the thickening of the lateral capsule that corresponds to a lateral collateral ligament, and the absence of a medial collateral ligament. Medial stability is conferred by the lateral ligament of the contralateral joint.

Aged↗

PubMed2003

General organization of the human intra-masseteric aponeuroses: changes with ageing.

A magnetic resonance imaging (MRI) study of the layout of the aponeurotic layers of the masseter muscle was done on a series of 18 patients, aged from 6 to 79 years. The study was undertaken in parallel with a study on 169 cadavers to correlate the anatomical dissection and MRI findings. The aims were as follows. On the cadavers, the results of dissection were compared with the results of MRI: the layer-by-layer dissections and the anatomical dissections of the different spatial planes have shown that the masseter muscle displays a penniform structure typically characterized by the presence of alternating muscular/aponeurotic layers. The anatomical sections and the MRI section in the same plane allowed the appearance of the intra-muscular aponeurotic layers on MRI to be defined. The patients were then divided into four age cohorts, and the arrangement and variations of the human masseter muscle defined as a function of age. This double study has brought new elements to the understanding of the timing of the development of the intra-muscular aponeurotic structures and the modifications which they undergo with ageing. It appears that the aponeurotic structures only become individually identifiable towards the age of 17 years and that ageing is accompanied by a reduction in the transverse muscular mass accompanied by a verticalization of the aponeurotic layers.

Adolescent↗

PubMed2003

Integrating self-referral for mammography into organised screening: results from an Italian experience.

OBJECTIVE: To compare self-referred screenees with respondents to invitation for main performance indicators of mammography screening. SETTING: First round of an organised, population-based screening programme in six districts of northern Italy. METHODS: The screening test was a two-view mammography. Eligible women aged 50-69 years were invited. Self-referred attendees were accepted if they were eligible for screening and had not yet been invited or had been invited >6 months before presentation. Age-specific performance indicators were compared with the calculation of their ratio and 95% confidence intervals (CIs). Total ratios were age standardised. In situ carcinomas were excluded. RESULTS: The eligible population was 183 542 women. There were 112 188 respondents to invitation and 20 280 self-referred attendees. Self-referral rate was inversely related to age. Performance indicators were as follows: recall rate, 5.6% for self-referred attendees vs 5.5% for respondents (ratio 1.02, 95% CI 0.96 to 1.08); total aspiration cytology rate, 37.3% vs 28.3% (1.37, 1.24 to 1.51); biopsy rate, 17.0 vs 12.6 x 1000 (1.51, 1.35 to 1.67); total detection rate, 10.7 vs 7.5 x 1000 (1.70, 1.48 to 1.94); detection rate of pT1 carcinoma, 7.0 vs 6.1 x 1000 (1.35, 1.14 to 1.59); detection rate of pT2-4 carcinoma, 3.5 vs 1.2 x 1000 (3.51, 2.75 to 4.43); false-positive rate, 4.5% vs 4.7% (0.93, 0.87 to 0.99); positive predictive value (PPV) of mammography, 19.1% vs 13.5% (1.59, 1.39 to 1.82); PPV of biopsy, 63.7% vs 60.6% (1.13, 0.98 to 1.29); detected:expected ratio, 5.02 vs 3.37 (1.49, 1.28 to 1.74). All differences were more pronounced among or restricted to women aged 50-54 years. CONCLUSIONS: Self-referred screenees were similar to respondents to invitation in main indicators of screening feasibility such as recall rate and PPV of biopsy, while showing important increases in detection rates and detected:expected ratios, especially among women aged 50-54 years.

Aged↗

PubMed2001

Functional anatomy of the human temporal muscle.

The authors carried out an anatomical and magnetic resonance imaging study on the architecture of the mandibular elevator muscles of 169 cadavers. The aim of the study was to define the organisational architecture of the human masseter, temporal and pterygoid muscles. Layer by layer dissection and anatomical cuts in different spatial planes showed that the temporal muscle has a different architecture to the other mandibular elevator muscles. Indeed this muscle does not have the pennate structure of the masseter and pterygoid muscles. Through electromyographic study the behavior of this muscle allowed the establishment of its functional segmentation during the masticatory cycle. Our study showed three distinct anatomical portions in the middle of the temporal muscle which correspond to this functional classification. The MRI study confirmed the results of our anatomical study.

Adult↗

PubMed2000

Functional organization of the human masseter muscle.

The authors carried out an anatomic and magnetic resonance imaging study of the architecture of the elevator muscles of the mandible in 169 cadavers. The aim of this study was to define the architectural organization of the human masseter muscle, temporalis and pterygoid muscles. Layered dissections and anatomic sections in different spatial planes showed that the masseter muscle exhibited a typical pennate structure consisting of a succession of alternating musculoaponeurotic layers. The muscle had three well-differentiated parts: the superficial, intermediate and deep masseter muscles. The same pattern was constantly found: 1) for the superficial masseter, two alternate musculoaponeurotic layers oriented at 60 degrees in relation to the plane of occlusion, 2) for the intermediate masseter, a single musculo-aponeurotic layer oriented at 90 degrees in relation to the occlusal plane, 3) for the deep masseter, three musculoaponeurotic layers whose general orientation was at 90 degrees for the bounding layers and 110 degrees for the intermediate layer. The MRI study confirmed the reality of this architectural arrangement.

Dissection↗

PubMed1998

Histologic changes in the sinus membrane after maxillary sinus augmentation in goats.

PURPOSE: Previous studies have reported on the morphologic aspects of bone regeneration after maxillary sinus grafting. However, no previous studies have examinated the morphology of the maxillary sinus mucosa after grafting. The purpose of this study was to evaluate the histologic changes in the lining membrane after sinus augmentation. MATERIALS AND METHODS: A unilateral osteotomy of the lateral maxillary wall, medial displacement of the bony segments, and elevation of the sinus mucosa were performed in 12 goats. An autogenous bone graft combined with coralline particles was placed on the floor of the sinus in three animals, and coralline particles alone were placed in three other goats. Six goats were not grafted and were used as controls. Samples were harvested at 2.5, 4.5, and 6.5 months. The maxillary sinus mucosa was examined using light microscopy and scanning and transmission electronic microscopy. RESULTS: The coralline particles were surrounded by fibrous connective tissue when used alone. The addition of iliac crest bone to the coralline particles stimulated bone formation. After the sinus augmentation, the mucosal lining showed a lack of glands in the lamina propria, and the epithelium showed an increase in goblet cells. CONCLUSION: It was concluded that the sinus mucosa undergoes physiologic adaptations and remains healthy and free of chronic sinusitis after maxillary sinus grafting.

Animals↗

PubMed1997

Solid nonpalpable breast lesions. Success and failure of guided fine-needle aspiration cytology in a consecutive series of 2444 cases.

PURPOSE: To evaluate the contribution of guided fine-needle aspiration cytology in reducing unnecessary biopsies of benign solid nonpalpable breast lesions with low suspicion of malignancy at mammography. MATERIAL AND METHODS: An evaluation was made of a consecutive series of 2444 solid nonpalpable breast lesions detected by mammography and undergoing guided (sonography or stereotaxy) fine-needle aspiration cytology. Surgical biopsy was made in the presence of strong suspicion of malignancy at mammography and/or of abnormal cytology. RESULTS: The sensitivity was 96.7% and the specificity 77.7% (average follow-up 2.77 years). False-negative/inadequate cytology associated with low suspicion of malignancy at mammography resulted in a diagnostic delay in 27 cancer cases (invasive 20, intraductal 7). On the other hand, cytology led to surgical biopsy in 53 cancer cases which might not otherwise have been biopsied because of low radiological suspicion of cancer. Surgical biopsy of all cases, to avoid diagnostic delays, would have increased the benign biopsy rate by a factor of 4.5, with a rise in the benign: malignant biopsy ratio from 0.44:1 to 1.93:1. CONCLUSION: Stereotaxy- or ultrasound-guided fine-needle aspiration cytology of nonpalpable mammographic abnormalities can achieve a sharp reduction in unnecessary benign biopsies in cases of low suspicion of malignancy at mammography.

Biopsy, Needle↗

PubMed1995

Wolfe's mammographic patterns in women with gross cystic disease of the breast.

The epidemiologic determinants of the mammographic pattern were studied in 710 patients with aspirated gross (> 1 ml) cysts of the breast. The prevalence of the mammograms classified as P2-DY, that are considered to be associated with an increased breast cancer risk, was 636/710 or 89.6%. No relationship between mammographic patterns and characteristics of breast cyst fluid such as K+/Na+ ratio, apocrine changes and dehydroepiandrosterone sulfate concentration was observed. A significant decrease in the proportion of these patterns with increasing age (p = 0.006), Quetelet Index (p < 0.001), parity (p = 0.001), and in postmenopausal women (p = 0.026) was found. Conversely, P2-DY patterns were significantly associated with a later age at menarche (p = 0.023) and alcohol consumption (p = 0.001). In multivariate analysis, an independent association with age was not observed whereas the associations with age at menarche, parity, and relative weight were confirmed. In conclusion, the epidemiologic determinants of mammographic patterns are the same in Gross Cystic Disease patients as in unaffected women, and the lack of correlation between mammographic pattern and cyst type suggests that the latter may represent an independent predictor of breast cancer risk.

Adult↗

PubMed1992

[Errors in mammography. II. False positives].

The authors evaluate 261 consecutive mammographic false positives observed from 1985 to 1987. Histological evidence of benign lesion followed in all cases. The comparison with the actual number of cancers and of the whole of mammographic examinations performed in the study period allowed specificity and positive predictive value of mammography to be assessed as 99.5% and 83%, respectively. Specificity and predictivity are lower in younger women, but this is more likely to depend on a different age-related incidence of cancer and benign lesions than on an intrinsic limitation of the method. The reader's diagnostic aggressivity, more than his experience, seems to affect both specificity and predictivity. At review, false positives were mostly due to asymmetric densities (49) or to circumscribed opacities with clear-cut (44) or blurred (62) outlines, whereas irregular star-like opacities or distortions (19) were infrequent. Microcalcifications were, in most cases, apparently benign (39) or dubious (76); strong suspicion was rare (4). Overall, one-fourth to one-third (27.9%) of the cases were reported as strongly suspicious at review. Palpation and cytology were also falsely suspicious--that is, co-responsible for unnecessary biopsies in over 50% of cases. Our results suggest that further improvement in the specificity or positive predictive value of mammography seems unlikely. Moreover, the benign/malignant biopsy ratio (0.2:1) presently achieved in suspicious mammographic cases appears quite satisfactory.

Adult↗

PubMed1991

Fine-needle cytology of the breast: a controlled study of aspiration versus nonaspiration.

We report on 534 breast masses examined by fine-needle aspiration cytology. Two samples were obtained from each mass, one with aspiration and the other without. Aspiration, equivalent to that obtained by a 20-ml syringe on full aspiration, was obtained by an automatic aspirator. The two sampling modalities did not differ apart from aspiration and were compared in terms of inadequate sampling rates. The inadequacy rate was the same in 166 cancers (6.6%), whereas a significant difference was recorded in favor of aspiration (13.6 versus 24.4%) in 368 benign masses. When inadequate results were excluded, the accuracy of the two modalities was almost the same. Sensitivity was 97.4% and 96.7% and specificity was 99.4% and 99.3% for sampling with and without aspiration, respectively. Reducing the rate of inadequate sampling from benign masses seems to be the major advantage of aspiration. Double sampling, independent of the specific techniques, reduced inadequacy rates to very low levels (1.2% for cancers; 5.9% for benign masses) and may be useful as a routine policy.

Biopsy, Needle↗

PubMed1991

[Diagnostic errors in mammography. I. False negative results].

The authors evaluate 1455 consecutive breast cancers detected 1985-1987, undergoing mammography 6 months before diagnosis at the most. One hundred and seventy-eight cases reported as negative/benign were assumed as false negatives. Overall sensitivity was 88%, and was influenced by tumor stage (TIS = 80%, T1 = 83%, T2 = 91%, T3-4 = 95%) and patients' age (less than 40 = 76%, 40-49 = 78%, 50-59 = 91%, greater than 59 = 94%). Sensitivity varied also with readers' experience full- or part-time involved in reading mammograms (total cases = 92% vs 88%, T1 cases = 86% vs 74%). No correlations were evidenced between mammographic sensitivity and histologic type of cancer. Palpation and cytology allowed the correct identification of 98% of mammographic false negatives. One hundred and seventy-eight false negatives and 142 more cases showing evidence of a mammographic error more than 6 months before diagnosis were reviewed to assess the most common types of radiologic fault. A benign-like lesion was the most frequent finding (49.4%), whereas suspicious signs were infrequent at review (16.6%). Failure to encompass the lesion in the mammographic field or poor technique accounted for 3.8 or 1.3% of cases, respectively. 29% of false-negative subjects (mostly young or with a dense breast) showed no lesion even at review. This study confirms the good sensitivity of mammography but suggests a less confident diagnostic approach in younger women, stresses the need for other tests whenever a minimal doubt is present, and encourages the radiologist's full-time involvement in mammography and breast diagnosis to achieve greater experience and improve his diagnostic sensitivity.

Adult↗

PubMed1991

[Differential diagnosis of intracystic breast lesions in hemorrhagic cysts].

The authors report on 117 consecutive hemorrhagic breast cysts cases. All patients underwent cytologic examination of cystic fluid content and US or pneumocystography. Ten cancers (9 infiltrating, and 1 lobular in situ) and 22 papillomas had histologic confirmation--out of 45 cases undergoing surgical biopsy. Seventy-two cases exhibiting no intracystic growth have been followed for 5.4 years on the average and no cancer has developed so far. Pneumocystography or US had 100% predictive value for intracystic lesions; we observed that surgical biopsy could be safely avoided when both examinations were negative, that is in about 3/4 cases. No differential diagnosis of cancer and papilloma was possible on pneumocystography or US. Even though positive cytology was highly predictive for cancer, cytology exhibited poor sensitivity and surgical biopsy was necessary in all cases presenting with intracystic growth.

Adult↗

PubMed1990

Prognostic impact of early detection of contralateral primary breast cancer.

The authors report on a consecutive series of 175 contralateral metachronous breast cancers. Eighty-six cases detected in women self referring for cancer-related subjective symptoms were compared to 89 cases detected as asymptomatic at routine examination. Detection in the asymptomatic phase was associated with a more favorable stage, but no differences in survival rates were observed between asymptomatic or symptomatic cancers when survival was measured from the date of first cancer diagnosis, in order to adjust for lead time bias. The nodal status of the first or of the second cancer was the only variable of prognostic value on univariate analysis, whereas a significant association to prognosis was evidenced only for nodal status of the first cancer. The study suggests that routine clinico-mammographic check-up may achieve early detection of contralateral metachronous breast cancer in the asymptomatic phase, but this does not seem to have a relevant impact on prognosis. The occurrence of a second primary breast cancer seems to be an indicator rather than a determinant of a worse prognosis.

Adult↗

PubMed1990

The role of fine needle aspiration cytology in the differential diagnosis of suspected breast cancer local recurrences.

The authors report on 228 cases of suspected breast cancer local recurrences studied by fine needle aspiration cytology (FNAC). The nature (malignant = 133, benign = 95) of suspected lesions was assessed on histology (no. = 46) or according to unequivocal follow-up (no. = 182). Inadequacy rate was 0.20, 0.09 or 0.35 in total, cancer or benign cases, respectively, and was particularly high (0.50) for benign chest wall lesions. Accuracy was determined on adequate smears; dubious reports were assumed as positive. Sensitivity and specificity were 0.96 and 0.97, respectively. The routine use of FNAC is recommended since it helps in the differential diagnosis of suspicious cases and may bypass surgical biopsy of positive cases not eligible for surgical treatment.

Biopsy, Needle↗