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Large-scale in-vivo Caucasian facial soft tissue thickness database for craniofacial reconstruction.

A large-scale study of facial soft tissue depths of Caucasian adults was conducted. Over a 2-years period, 967 Caucasian subjects of both sexes, varying age and varying body mass index (BMI) were studied. A user-friendly and mobile ultrasound-based system was used to measure, in about 20min per subject, the soft tissue thickness at 52 facial landmarks including most of the landmarks used in previous studies. This system was previously validated on repeatability and accuracy [S. De Greef, P. Claes, W. Mollemans, M. Loubele, D. Vandermeulen, P. Suetens, G. Willems, Semi-automated ultrasound facial soft tissue depth registration: method and validation. J. Forensic Sci. 50 (2005)]. The data of 510 women and 457 men were analyzed in order to update facial soft tissue depth charts of the contemporary Caucasian adult. Tables with the average thickness values for each landmark as well as the standard deviation and range, tabulated according to gender, age and BMI are reported. In addition, for each landmark and for both sexes separately, a multiple linear regression of thickness versus age and BMI is calculated. The lateral asymmetry of the face was analysed on an initial subset of 588 subjects showing negligible differences and thus warranting the unilateral measurements of the remaining subjects. The new dataset was statistically compared to three datasets for the Caucasian adults: the traditional datasets of Rhine and Moore [J.S. Rhine, C.E. Moore, Tables of facial tissue thickness of American Caucasoids in forensic anthropology. Maxwell Museum Technical series 1 (1984)] and Helmer [R. Helmer, Schädelidentifizierung durch elektronische bildmischung, Kriminalistik Verlag GmbH, Heidelberg, 1984] together with the most recent in vivo study by Manhein et al. [M.H. Manhein, G.A. Listi, R.E. Barsley, R. Musselman, N.E. Barrow, D.H. Ubelbaker, In vivo facial tissue depth measurements for children and adults. J. Forensic Sci. 45 (2000) 48-60]. The large-scale database presented in this paper offers a denser sampling of the facial soft tissue depths of a more representative subset of the actual Caucasian population over the different age and body posture subcategories. This database can be used as an updated chart for manual and computer-based craniofacial approximation and allows more refined analyses of the possible factors affecting facial soft tissue depth.

Adolescent↗

Obstructive sleep apnea syndrome: hooked appearance of the soft palate in awake patients--cephalometric and CT findings.

PURPOSE: To determine whether a hooked appearance of the soft palate can be seen in awake patients with snoring with or without obstructive sleep apnea syndrome (OSAS) on cephalometric radiographs and computed tomographic (CT) scans. MATERIALS AND METHODS: One hundred thirty-one patients with snoring underwent cephalometric radiography, with which the posterior airway space, soft palate length and width, and distance between the hyoid bone and mandibular plane were measured, and/or pharyngeal CT, with which the luminal areas of the airway at the naso-, oro-, and hypopharyngeal levels were measured. RESULTS: Of the 131 patients, 96 had OSAS, and 35 had snoring. Nine of 96 patients with OSAS had soft palate hooking on awake pharyngeal CT or cephalometric images. No patient with snoring alone had hooking. Patients with hooking had a larger posterior airway space than did patients with OSAS without hooking (P = .05), and an enlarged (> or = 15-mm) posterior airway space was more frequent in patients with hooking (eight of nine patients) than in those without hooking (34 of 87) (P < .01). Oropharyngeal and hypopharyngeal areas were significantly larger in patients with hooking than in patients without hooking or in patients with snoring (P < or = .04). CONCLUSION: Cephalometric radiography and CT can demonstrate hooking of the soft palate in awake patients. This finding indicates a high risk for OSAS.

Adult↗

[3D-ultrasound of soft tissues and joints].

Sonography has become a reliable diagnostic method in musculo-skeletal diseases. It allows a simple and noninvasive examination of joints and soft tissues. Especially in rheumatic diseases meaningful findings can be obtained. In the present study first results of three-dimensional (3D) sonography of the musculo-skeletal system are reported. The method was first validated by examining healthy test persons and criteria for regular findings were defined. In the second part of the study an unselected group of patients with inflammatory and noninflammatory joint and soft tissue diseases were examined and the obtained results were compared with the findings of the conventional real-time sonography. Comparison of the 2D and 3D procedure showed a superiority of the 3D method with regard to the assessment of large (hip), middle-sized (elbow) and small joints (finger, toe). Additional information about the synovial space, the surface of the cartilage, and the thickness of the synovial membrane was provided by 3D sonography. Volumetry of joint effusions and Baker cysts was easier to perform and more reliable than with the conventional method. Soft tissue alterations could be delineated reliably, depending on their size. Our results demonstrate that 3D sonography can improve the diagnostics of musculo-skeletal diseases. In the future, 3D sonography should play an important part in the diagnosis of joint and soft tissue diseases.

Arthritis, Rheumatoid↗

Variable site of oropharyngeal narrowing and regional variations of oropharyngeal collapsibility among snoring patients during wakefulness and sleep.

The oropharynx shows rhythmic caliber changes in accordance with the respiratory cycle. Dynamic imaging of the oropharynx is required to evaluate airway changes associated with snoring and obstructive sleep apnea. The purpose of this study was to determine the sites of narrowing/obstruction and to measure the regional collapsibility of the oropharynx during respiration during the sleep and awake cycles in snoring patients. Seven snoring patients were included for this study. Electron Beam Tomograms of the oropharynx were taken while the patient was awake and asleep, and dynamic views were reconstructed. The site of narrowing or obstruction varied widely among patients and differed from awake to asleep. The mean of smallest minimum cross-sectional area of the oropharynx was 60.38+/-42.97 mm2 in the awake state and 16.90+/-20.43 mm2 in the asleep state. Although the collapsibility of the oropharynx showed considerable regional variations, it increased during sleep at the overall oropharynx. The low retropalatal region showed the smallest minimum cross-sectional area and the highest collapsibility; however, the most prominent changes in the minimum cross-sectional area and collapsibility during sleep were observed in the high retroglossal region.

Adult↗

Inflammatory abdominal aortic aneurysm: a cause of urinary obstruction and acute renal failure.

Abdominal aortic aneurysms are rare causes of ureteric obstruction. We report three cases of inflammatory abdominal aortic aneurysm producing hydronephrosis. In two patients acute renal failure preceded this presentation. The diagnosis can be established by computed tomography when mural thrombus, wall calcification, and an enhancing periaortic soft-tissue mantle are present. It is important to recognize this disease preoperatively.

Acute Kidney Injury↗

Malignant soft-tissue tumors in a large referral population: distribution of diagnoses by age, sex, and location.

OBJECTIVE: The purpose of this study was to determine the relative prevalence, age at presentation, sex distribution, and skeletal distribution of malignant soft-tissue tumors and to ascertain the relative frequency of these tumors in specific anatomic locations and age groups among a population of patients in a large pathologic consultation service. MATERIALS AND METHODS: The computer diagnoses of 39,179 lesions occurring in 38,484 patients seen by soft-tissue pathologists at the Armed Forces Institute of Pathology during the 10-year period from January 1, 1980, to December 31, 1989, were retrospectively reviewed. All lesions were placed in one of 121 major categories in accordance with the classification system used by the World Health Organization and coded to one of 32 anatomic locations, such as hand, wrist, forearm, and so forth. Age and sex also were recorded. For purposes of analysis, all lesions were placed in one of 10 categories: hand and wrist, upper extremity, proximal limb girdle (axilla and shoulder), foot and ankle, lower extremity, hip and buttocks region, head and neck, trunk, retroperitoneum, and other lesions. The study group included 31,047 mesenchymal lesions, of which 12,370 were malignant. RESULTS: More than 80% of malignant tumors were classified into eight diagnostic categories: malignant fibrous histiocytoma (24%), liposarcoma (14%), leiomyosarcoma (8%), malignant schwannoma (6%), dermatofibrosarcoma protuberans (6%), synovial sarcoma (5%), fibrosarcoma (5%), and sarcoma, not classified further (12%). Approximately 79% of all malignant tumors were classified into five diagnoses for each age and location. With the distal upper extremity (hand and wrist) as an example, 50% of malignant lesions in the 16-25-year-old group were classified as epithelioid sarcoma (29%), malignant fibrous histiocytoma (13%), and synovial sarcoma (8%). For the same location but for children 5 years old or younger, almost 50% of malignant tumors were classified as infantile fibrosarcoma. CONCLUSION: Despite the multitude of pathologic possibilities, most malignant soft-tissue tumors are classified into a small number of diagnoses. These may be further defined when the location of the lesion and the age of the patient are considered. Knowledge of tumor prevalence will assist radiologists in establishing a suitably ordered differential diagnosis when a soft-tissue tumor has a nonspecific radiologic appearance.

Adolescent↗

Neoplastic involvement of the sacroiliac joint: MR and CT features.

The radiological findings in five patients with pelvic soft tissue neoplasms directly involving the sacroiliac joint, are described. All patients had Computed Tomography (CT) examinations, two of the patients also having Magnetic Resonance Imaging (MRI). The role of imaging in this uncommon entity is discussed as well as the importance of making this diagnosis, thereby excluding unilateral sacroiliitis. The therapeutic implications of this diagnosis relate to local neural involvement, especially the sciatic nerve, and the fact that involvement of the sacroiliac joint by tumors significantly compromises chances of a successful surgical outcome. The role of MR in this condition is not yet certain, but it may prove to be the method of choice in view of its excellent depiction of skeletal neoplasms.

Adult↗

Computed tomography of the infratemporal fossa in primary jaw pathology.

Due to the anatomical relationship of the jaws to the infratemporal fossa this area is readily involved in pathological processes of the jaw. Conventional radiographs play a limited role in demonstrating this region. A variety of primary diseases of the jaws, namely hereditary, developmental, infective, benign and malignant tumours with extension into the infratemporal fossa, are presented. Computed tomography is an excellent method for showing both osseous and soft-tissue components which include bony destruction, new bone formation, soft tissue calcification, inflammatory and malignant processes affecting the muscles and fat in the infratemporal fossa.

Adolescent↗

Idiopathic orbital inflammation with sclerosing mesenteritis: a new association?

A 70-year-old man, who was recently diagnosed with sclerosing mesenteritis following an abdominal biopsy, presented with an acute onset of left upper eyelid swelling, moderate ptosis, mild chemosis and restriction of movements. A computed tomography scan showed an enlarged lateral rectus muscle with surrounding soft tissue changes. A diagnosis of orbital inflammation manifesting as myositis was made and the patient was commenced on high-dose prednisolone, which showed a rapid response. It is believed that this may be a new association similar to that previously reported with retroperitoneal fibrosis and orbital inflammation.

Aged↗

Incidence, investigations and staging of soft-tissue sarcoma.

Soft-tissue sarcomas account for only 1% of all malignant lesions. The Canadian Sarcoma Group encourages the investigation and management of these tumours at tertiary institutions, where a multidisciplinary team can handle the complex problems. Staging of these tumours implies accurate anatomic determination of the extent of disease, the histogenesis and grade of the tumours and the presence of regional or distant metastases. Arteriography, computed tomography and magnetic resonance imaging can accurately define the tumour before biopsy. The biopsy should be muscle-splitting to minimize contamination of additional compartments and should allow inclusion of the biopsy site at definitive surgical resection. It should be done at the institution where definitive management will be performed. Regional lymph-node involvement can be detected using magnetic resonance imaging or gallium scanning, whereas for distant metastases, specifically of lung, computed tomography is the method of choice. To date no one staging system for soft-tissue sarcomas has been universally accepted. A hybrid, encompassing the advantages of each system, is being formulated.

Biopsy↗

Bilateral ocular scrofuloderma with orbital tuberculosis.

Ocular scrofuloderma with orbital tuberculosis is a rarely described presentation of childhood tuberculosis. Bilateral involvement has not been reported earlier in the medical literature. Here is reported a 3-year-old boy who presented with bilateral infraorbital swellings of tubercular etiology. Computed tomography (CT) scan of the upper face revealed enhancing soft tissue lesions in both the lower lids of the eyes, with extraconal extension into the orbits and with erosion of the right zygomatic bone. Tubercular etiology was confirmed by the Ziehl Neelsen staining of the aspirate from the lesion, which was positive for acid-fast bacilli and growth of Mycobacterium tuberculosis in the aspirate culture. The patient showed marked improvement of his lesions on anti-tubercular treatment.

Child, Preschool↗

Hyperplastic callus formation in osteogenesis imperfecta: CT and MRI findings.

Hyperplastic callus formation is a noteworthy condition in patients with osteogenesis imperfecta because it often mimicks osteosarcoma on radiography. The findings of CT and MRI in hyperplastic callus formation have not been reported. In the presented case, MRI demonstrated contrast enhancement and edema of the surrounding soft tisssue, consistent with benign as well as malignant disease. Computed tomography showed a calcified rim of the lesion which may be a useful feature to rule out osteosarcoma in this condition.

Adult↗

Tuberculous bursitis of the greater trochanter.

A patient with tuberculous bursitis of the greater trochanter is reported. A 37-year-old woman had experienced persistent dull hip pain and noticed diffuse swelling over the greater trochanteric region. Plain radiograph revealed unremarkable osteopenic changes in the greater trochanter and faint mineralization in the vicinity of the trochanter. Computed tomogram showed erosion of the trochanter and a large soft tissue mass. Magnetic resonance imaging demonstrated a large multicystic mass. Histology of the cyst wall, showing chronic granulomatous tissue, and a positive culture of Mycobacterium tuberculosis confirmed the diagnosis of musculoskeletal tuberculosis. Complete excision of the lesion, followed by 6 months of antituberculous chemotherapy with rifampicin and isoniazid, cured the disease. There has been no sign of recurrent disease in 30 months of follow-up. Correct diagnosis was difficult because of its rarity, but modern imaging technology, magnetic resonance imaging, in particular, was extremely useful for showing the extent of the disease. Tuberculous infection should be considered as a differential diagnosis in patients with persistent hip pain.

Adult↗

Magnetic resonance imaging of oral and maxillofacial angiomas.

Eleven patients with oral and maxillofacial angiomas (seven hemangiomas and four lymphangiomas) were evaluated with magnetic resonance imaging using a 0.2-T permanent system and spin-echo pulse sequences. These lesions typically had signal intensities that were iso T1-weighted, similar to muscle, and high T2-weighted, greater than subcutaneous fat. Nine tumors had well- or relatively well-defined margins, and seven cases had curvilinear structures of low signal intensities in the masses on T2-weighted images. It was impossible to distinguish hemangiomas from lymphangiomas on MR images. Our experience suggested that most angiomas of oral and maxillofacial regions present special characteristics on magnetic resonance images. It is thought that information obtained with magnetic resonance images can contribute significantly to the evaluation of the extent of these lesions.

Adolescent↗

Influence of hyoepiglotticus muscle contraction on canine upper airway geometry.

We examined the effect of hyoepiglotticus (HE) muscle contraction on epiglottic position in 4 anaesthetised (IV choralose, pentobarbitone sodium) tracheostomised, mechanically ventilated dogs studied in the prone mouth open position. Computerised axial tomography (coronal plane) was used to measure the vertical distance between the tip of the epiglottis (E) and (1) the soft palate (SP) (i.e. E-SP distance) and (2) the dorsal wall of the nasopharynx (N) (i.e. E-N distance). Duplicate runs of graded electrical stimulation of the HE muscle, using bilateral bipolar fine wire electrodes, were performed in each animal and resulted in a progressive increase in both the E-SP distance (baseline of 0.5 +/- 0.5 to a maximum of 13.1 +/- 2.3 mm, mean +/- SE) and the E-N distance (29.1 +/- 2.0 to a maximum of 42.2 +/- 2.7 mm, both p < 0.02). We conclude that HE contraction moves the epiglottis ventrally away from the soft palate thus opening and enlarging the oral pathway for airflow.

Animals↗

Effects of perfusion on the viscoelastic characteristics of liver.

Accurate characterization of soft tissue material properties is required to enable new computer-aided medical technologies such as surgical training and planning. The current means of acquiring these properties in the in vivo and ex vivo states is fraught with problems, including limited accessibility and unknown boundary conditions in the former, and unnatural behavior in the latter. This paper presents a new testing method where a whole porcine liver is perfused under physiologic conditions and tested in an ex vivo setting. To characterize the effects of perfusion on the viscoelastic response of liver, indentation devices made force and displacement measurements across four conditions: in vivo, ex vivo perfused, ex vivo post perfused, and in vitro on an excised section. One device imposed cyclic perturbations on the liver's surface, inducing nominal strains up to 5% at frequencies from 0.1 to 200 Hz. The other device measured 300 s of the organ's creep response to applied loads, inducing nominal surface stresses of 6.9-34.7 kPa and nominal strains up to 50%. Results from empirical models indicate that the viscoelastic properties of liver change with perfusion and that two time constants on the order of 1.86 and 51.3s can characterize the liver under large strains typical of surgical manipulation across time periods up to 300 s. Unperfused conditions were stiffer and more viscous than the in vivo state, resulting in permanent strain deformation with repeated indentations. Conversely, the responses from the ex vivo perfusion condition closely approximated the in vivo response.

Animals↗

Digitized analysis of abnormal hand-motor performance in schizophrenic patients.

Many studies have shown a high prevalence of discrete neuromotor disturbances in schizophrenic patients. It was hypothesized that these disturbances are lateralized and reflect a neurodevelopmental disorder underlying schizophrenia. A new method for assessing subtle motor dysfunction and hemispheric asymmetries is the registration of hand movements with a digitizing tablet. Using this method, we studied hand-motor dysfunction and its lateralization in schizophrenics, as compared with healthy controls. All subjects (27 schizophrenic patients, 13 of them without neuroleptic medication, the others under neuroleptics; 31 healthy controls) drew super-imposed concentric circles. We computed kinematic parameters reflecting velocity and automatization to quantify neurological soft signs (NSS). The patients had significant impairments of regularity of repetitive hand movements, as compared with the healthy controls (F> or =5.35; p< or =0.024(*)). Comparing differences of left- and right-hand performance between patients and controls, we found longer stroke duration (F=(15,98); p=0.000***) and decreased automatization (F=18,14; p=0.000***), especially on the left side in schizophrenic patients. Measuring hand movements with a digitizing tablet is a sensitive method for assessing subtle motor dysfunction in schizophrenic patients, not reflected in the scores of clinical scales. Our findings show NSS in schizophrenic patients, independently of neuroleptics. Further, the hypothesis of lateralization of cerebral structures generating NSS towards the right hemisphere in schizophrenia is supported.

Adult↗

Cystic degeneration in fibrous dysplasia of the jaws: a case report.

A case of nonspecific cystic degeneration complicating fibrous dysplasia of the mandible is presented. This condition is extremely rare in the jaw bones. The patient had a painless swelling of the right face measuring 10 cm in diameter, and there was no history of trauma. Radiographs showed a poorly defined, "ground glass" radiopaque lesion; a central well-defined cyst was confirmed by means of computed tomography. During surgery, a large cystic cavity with surrounding, soft fibrous bone that merged with the cortex was observed. Histologic examination showed a large non-epithelial-lined cystic cavity with a surrounding fibro-osseous lesion, which was consistent with a diagnosis of fibrous dysplasia.

Child↗