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1.
Biomech Model Mechanobiol ; 16(4): 1171-1185, 2017 08.
Article in English | MEDLINE | ID: mdl-28210824

ABSTRACT

Most current cartilage testing devices require the preparation of excised samples and therefore do not allow intra-operative application for diagnostic purposes. The gold standard during open or arthroscopic surgery is still the subjective perception of manual palpation. This work presents a new diagnostic method of ultrasound palpation (USP) to acquire applied stress and strain data during manual palpation of articular cartilage. With the proposed method, we obtain cartilage thickness and stiffness. Moreover, repeated palpations allow the quantification of relaxation effects. USP measurements on elastomer phantoms demonstrated very good repeatability for both, stage-guided (97.2%) and handheld (96.0%) applications. The USP measurements were compared with conventional indentation experiments and revealed very good agreement on elastomer phantoms ([Formula: see text]) and good agreement on porcine cartilage samples ([Formula: see text]). Artificially degenerated cartilage samples showed reduced stiffness, weak capacity to relax after palpation and an increase of stiffness of approximately 50% with each single palpation. Intact cartilage was measured by USP directly at the patella (in situ) and after excision and removal of the subchondral bone (ex situ), leading to stiffness values of [Formula: see text] and [Formula: see text] ([Formula: see text]), respectively. The results demonstrate the potential of the USP system for cartilage testing, its sensitivity to degenerative changes and as a method for quantifying relaxation processes by means of repeated palpations. Furthermore, the differences in the results of in-situ and ex-situ measurements are of general interest, since such comparison has not been reported previously. We point out the limited comparability of ex-situ cartilage with its in-situ biomechanical behavior.


Subject(s)
Cartilage, Articular/diagnostic imaging , Ultrasonography , Animals , Biomechanical Phenomena , Palpation , Patella , Reproducibility of Results , Swine
2.
Eur Cell Mater ; 31: 119-35, 2016 Feb 08.
Article in English | MEDLINE | ID: mdl-26853622

ABSTRACT

Objective and sensitive assessment of cartilage repair outcomes lacks suitable methods. This study investigated the feasibility of 3D ultrasound biomicroscopy (UBM) to quantify cartilage repair outcomes volumetrically and their correlation with established classification systems. 32 sheep underwent bilateral treatment of a focal cartilage defect. One or two years post-operatively the repair outcomes were assessed and scored macroscopically (Outerbridge, ICRS-CRA), by magnetic resonance imaging (MRI, MOCART), and histopathology (O'Driscoll, ICRS-I and ICRS-II). The UBM data were acquired after MRI and used to reconstruct the shape of the initial cartilage layer, enabling the estimation of the initial cartilage thickness and defect volume as well as volumetric parameters for defect filling, repair tissue, bone loss and bone overgrowth. The quantification of the repair outcomes revealed high variations in the initial thickness of the cartilage layer, indicating the need for cartilage thickness estimation before creating a defect. Furthermore, highly significant correlations were found for the defect filling estimated from UBM to the established classification systems. 3D visualisation of the repair regions showed highly variable morphology within single samples. This raises the question as to whether macroscopic, MRI and histopathological scoring provide sufficient reliability. The biases of the individual methods will be discussed within this context. UBM was shown to be a feasible tool to evaluate cartilage repair outcomes, whereby the most important objective parameter is the defect filling. Translation of UBM into arthroscopic or transcutaneous ultrasound examinations would allow non-destructive and objective follow-up of individual patients and better comparison between the results of clinical trials.


Subject(s)
Bone and Bones/diagnostic imaging , Cartilage, Articular , Microscopy, Acoustic/methods , Animals , Bone Development/physiology , Bone and Bones/cytology , Cartilage, Articular/diagnostic imaging , Cartilage, Articular/injuries , Cartilage, Articular/surgery , Double-Blind Method , Female , Prospective Studies , Random Allocation , Reproducibility of Results , Sheep , Wound Healing/physiology
3.
Nervenarzt ; 86(5): 595-602, 2015 May.
Article in German | MEDLINE | ID: mdl-25631120

ABSTRACT

BACKGROUND: The term neonaticide describes the act of killing a newborn child by a parent (mostly by the mother) within 24 h after birth. The aim of this study was to establish a classification of female perpetrators using psychopathological, mental, social and biographical characteristics and to make a comparison of the frequency between the old and new federal states in Germany. MATERIAL AND METHODS: In this study a total of 63 female German perpetrators who killed at least one newborn between 1986 and 2009 are portrayed and classified by epidemiological and psychopathological characteristics and personality profiles. After obtaining consent from the public prosecutors responsible, data were collected from forensic psychiatric expert opinions and legally valid court verdicts. A questionnaire was established to answer the questions on the psychopathological, e.g. do the women suffer from a mental disease when killing their newborn(s), mental, e.g. can personality accentuations be elicited, social, e.g. are the women unemployed and biographical characteristics of the women, e.g. how old are the women? Finally, an investigation was carried out using significance tests to find out if there was a significant statistical difference in the frequency of neonaticide between the eastern and western federal states. RESULTS: A cluster analysis based on the descriptive analysis was developed. The cluster analysis provided a foundation for a dichotomous classification of the perpetrators depending on five criteria. The first category contained 32 perpetrators who were on average 21 years old, who were primiparous and who hid, ignored or did not perceive their pregnancy. Most of them still lived with their parents. The perpetrators either did not have a mental disease or suffered from an acute stress disorder. The second category contained 31 perpetrators who were on average 25 years old, who were pluriparous, who hid their pregnancy and who lived with their partner. These women either did not have a mental disease or suffer from a personality disorder. A statistically significant higher incidence was found in the eastern federal states of Germany. CONCLUSION: The presented categorization of female perpetrators into two groups, where the features only show a small degree of overlap, should be taken into consideration in the assessment of the reasons for neonaticide. The typology of female perpetrators is more heterogeneous than previously assumed. The presented typologies and knowledge of conditional constellations involved in neonaticide achieve better prerequisites to be able to recognize persons at risk earlier and to instigate preventive measures.


Subject(s)
Criminals/psychology , Infanticide/psychology , Infanticide/statistics & numerical data , Mental Disorders/psychology , Mothers/psychology , Women/psychology , Adult , Age Distribution , Female , Germany, East/epidemiology , Germany, West/epidemiology , Humans , Incidence , Infant, Newborn , Mental Disorders/epidemiology , Mothers/statistics & numerical data , Risk Factors , Unemployment/psychology , Unemployment/statistics & numerical data
4.
Osteoarthritis Cartilage ; 22(10): 1577-82, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25278067

ABSTRACT

CONTEXT: To date only single ultrasound parameters were regarded in statistical analyses to characterize osteoarthritic changes in articular cartilage and the potential benefit of using parameter combinations for characterization remains unclear. OBJECTIVE: Therefore, the aim of this work was to utilize feature selection and classification of a Mankin subset score (i.e., cartilage surface and cell sub-scores) using ultrasound-based parameter pairs and investigate both classification accuracy and the sensitivity towards different degeneration stages. DESIGN: 40 punch biopsies of human cartilage were previously scanned ex vivo with a 40-MHz transducer. Ultrasound-based surface parameters, as well as backscatter and envelope statistics parameters were available. Logistic regression was performed with each unique US parameter pair as predictor and different degeneration stages as response variables. The best ultrasound-based parameter pair for each Mankin subset score value was assessed by highest classification accuracy and utilized in receiver operating characteristics (ROC) analysis. RESULTS: The classifications discriminating between early degenerations yielded area under the ROC curve (AUC) values of 0.94-0.99 (mean ± SD: 0.97 ± 0.03). In contrast, classifications among higher Mankin subset scores resulted in lower AUC values: 0.75-0.91 (mean ± SD: 0.84 ± 0.08). Variable sensitivities of the different ultrasound features were observed with respect to different degeneration stages. CONCLUSIONS: Our results strongly suggest that combinations of high-frequency ultrasound-based parameters exhibit potential to characterize different, particularly very early, degeneration stages of hyaline cartilage. Variable sensitivities towards different degeneration stages suggest that a concurrent estimation of multiple ultrasound-based parameters is diagnostically valuable. In-vivo application of the present findings is conceivable in both minimally invasive arthroscopic ultrasound and high-frequency transcutaneous ultrasound.


Subject(s)
Cartilage Diseases/diagnostic imaging , Cartilage, Articular/diagnostic imaging , Osteoarthritis, Knee/diagnostic imaging , Cartilage Diseases/etiology , Cartilage Diseases/pathology , Cartilage, Articular/pathology , Case-Control Studies , Humans , Logistic Models , Osteoarthritis, Knee/complications , ROC Curve , Ultrasonography
5.
Ultrasound Med Biol ; 39(5): 834-44, 2013 May.
Article in English | MEDLINE | ID: mdl-23465134

ABSTRACT

High-frequency ultrasound (US) surface parameters are well known to be sensitive to degenerative changes in cartilage tissue, but estimates deteriorate if the sample is inclined. We propose 3-D US to precisely estimate the local surface and inclination. For this purpose, the most common ultrasonic surface parameters ultrasound roughness index and integrated reflection coefficient were extended to 2-D surface measurements. Tissue-mimicking phantoms and human cartilage samples with varying degrees of degeneration were measured using a 40-MHz transducer. Characteristic inclination dependencies of the parameters aided in the distinction between specular reflected or backscattered signal origins and allowed a restriction to suitable local inclinations. In the application to cartilage, comparisons with histologic grading (structural Mankin-score) depicted a statistically significant (p < 0.05) increase of US roughness index for scores larger than 0 and decrease of integrated reflection coefficient for scores larger than 1. The presented findings will increase the reliability of ultrasonic surface parameters and can in principal be applied in vivo.


Subject(s)
Algorithms , Cartilage, Articular/diagnostic imaging , Image Enhancement/methods , Image Interpretation, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , Osteoarthritis/diagnostic imaging , Ultrasonography/methods , Humans , Phantoms, Imaging , Reproducibility of Results , Sensitivity and Specificity , Surface Properties , Ultrasonography/instrumentation
9.
Zentralbl Gynakol ; 119 Suppl 1: 8-16, 1997.
Article in German | MEDLINE | ID: mdl-9245126

ABSTRACT

From 1973 through 1993, the University of Leipzig Women's Hospital treated 285 patients with primary vulvar malignancies. Of these, 269 cases (94.3%) were squamous cell carcinomas. The patients age averaged 69 years (25-95 years). 232 women (81.4%) were older than 60 years. Only 20 women (7%) were younger than 50 years. During the given time period, 266 patients (93.3%) underwent primary surgery. Standard operative treatment, performed in 105 cases (39.5%), was radical vulvectomy and bilateral superficial inguinal lymph node dissection. Rather than en bloc resection (Butterfly method), separate incisions were used during node dissection. Only 3 patients (2.9%) experienced a relapse within the remaining skin bridge. Irradiation with a focal doses of ca. 50 Gy followed postoperative-adjuvant in those cases involving the inguinal lymph nodes. In contrast, 161 patients received largely individualized surgical treatment. Local tumor extension and patient age-dependent operability influenced the choice of treatment. Partial vulvectomy was performed in 37 cases (13.9%). Simple vulvectomy without inguinal node dissection was performed in 115 cases (43.2%) and 9 patients underwent vulvectomy with vaginal-, urethral- and partial sphincter resection, accompanied by myocutaneous flap transposition (M. gluteus maximus lobe). The cumulative (corrected) 5-year survival rate for all patients with squamous cell carcinoma was 68.6%. No significant relationship between patient age (> 60 years vs. < or = 60 years) and prognosis could be seen. Factors of importance to the prognosis, however, were primary tumor size (FIGO stage I vs. II vs. III/IV), principal tumor site (significantly poorer survival rates characterize both clitoral and multifocal carcinomas), histological staging (G1 vs. G2/G3), inguinal lymph node involvement (pN+ vs. pN-) and degree of tumor resection in "healthy" (> or = 2 cm vs. < 2 cm). 5-year survival rates among those patients receiving individualized operative care did not differ significantly. Patient survival rates were 70.3% by partial vulvectomy, 78.2% by simple vulvectomy without inguinal node dissection and 67.6% by radical vulvectomy and bilateral inguinal node dissection with or without postoperative-adjuvant irradiation. These findings, therefore, justify the individualized operative treatment of patients with vulvar carcinoma according to each patient's initial prognostic situation. The relatively seldom vulvar carcinoma should only be treated by experienced surgeons in an appropriate hospital environment. Moreover, assessment of histological sections must be standardized, reproducible and above all, include the very accurate evaluation of all resection edges.


Subject(s)
Carcinoma, Squamous Cell/surgery , Vulvar Neoplasms/surgery , Adult , Aged , Aged, 80 and over , Carcinoma, Squamous Cell/mortality , Carcinoma, Squamous Cell/pathology , Female , Humans , Lymph Node Excision , Middle Aged , Neoplasm Recurrence, Local , Neoplasm Staging , Prognosis , Radiotherapy, Adjuvant , Surgical Flaps , Surgical Procedures, Operative/methods , Survival Rate , Vulvar Neoplasms/mortality , Vulvar Neoplasms/pathology
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