Sound fields caused by diffuse‐type reflectors with periodic profile

1998 ◽  
Vol 103 (5) ◽  
pp. 3066-3066
Author(s):  
Daiji Takahashi
2000 ◽  
Vol 21 (3) ◽  
pp. 131-143 ◽  
Author(s):  
Daiji Takahashi ◽  
Yoshikuni Kato ◽  
Ken Sakamoto

1999 ◽  
Vol 91 (1) ◽  
pp. 105-111 ◽  
Author(s):  
Kenji Ohata ◽  
Toshihiro Takami ◽  
Alaa El-Naggar ◽  
Michiharu Morino ◽  
Akimasa Nishio ◽  
...  

✓ The treatment of spinal intramedullary arteriovenous malformations (AVMs) with a diffuse-type nidus that contains a neural element poses different challenges compared with a glomus-type nidus. The surgical elimination of such lesions involves the risk of spinal cord ischemia that results from coagulation of the feeding artery that, at the same time, supplies cord parenchyma. However, based on evaluation of the risks involved in performing embolization, together with the frequent occurrence of reperfusion, which necessitates frequent reembolization, the authors consider surgery to be a one-stage solution to a disease that otherwise has a very poor prognosis. Magnetic resonance (MR) imaging revealed diffuse-type intramedullary AVMs in the cervical spinal cords of three patients who subsequently underwent surgery via the posterior approach. The AVM was supplied by the anterior spinal artery in one case and by both the anterior and posterior spinal arteries in the other two cases. In all three cases, a posterior median myelotomy was performed up to the vicinity of the anterior median fissure that divided the spinal cord together with the nidus, and the feeding artery was coagulated and severed at its origin from the anterior spinal artery. In the two cases in which the posterior spinal artery fed the AVM, the feeding artery was coagulated on the dorsal surface of the spinal cord. Neurological outcome improved in one patient and deteriorated slightly to mildly in the other two patients. Postoperative angiography demonstrated complete disappearance of the AVM in all cases. Because of the extremely poor prognosis of patients with spinal intramedullary AVMs, this surgical technique for the treatment of diffuse-type AVMs provides acceptable operative outcome. Surgical intervention should be considered when managing a patient with a diffuse-type intramedullary AVM in the cervical spinal cord.


2019 ◽  
Vol 72 (12) ◽  
Author(s):  
Olena O Dyadyk ◽  
Anastasiia Hryhorovska

Introduction: Tenosynovial giant cell tumor (TSGCT) (synonym – pigmented villonodular synovitis) – is a rare benign proliferative lesion of the synovial sheath, localized in the joint capsule, bursa or tendon sheath and characterized by locally destructive growth. Depending on the prevalence within the joint elements, the presence of a capsule around the tumor, histophotographic features of cell structure and clinical behavior TSGCT can be divided to localized or diffuse type. The aim of the study was researching of histopathological properties of diffuse-type TSGCT, determine the parameters its morphological indicators and to find out the correlation between these morphological and clinical parameters. Materials and methods: The research material was used biopsy (resect) of pathological lesions from 50 patients who were diagnosed and histologically verified diffuse-type TSGCT. Microscopic examinations of the stained sections and their photo archiving were carried out with use of a Olympus-CX 41 light optical microscope. Group measurable parameters (mean values and Pearson tetrachoric index (association coefficient) were calculated in groups of comparison for morphological and clinical indices of TSGCT. The mean values were compared by Student’s test, P value of ≤0.1 was considered statistically significant. Results:Correlation analysis of indicators that accounted for the pairs of cases «clinic – morphology» revealed the relationships, that had the highest parameters of the association coefficient between such indicators: «presence of villous growths» - «severity of hemosiderosis» (if hypertrophied synovial villi available, with vascular injection and pronounced proliferation of synovial cells, there is also a significant accumulation of hemosiderin pigment); «presence of villous growths» - «type of predominant cellular proliferates» (if cells of TSGCT diffuse type consists of monotonous sheets of stromal cells, with uniform, oval to reniform nuclei, the proliferation of villi in synovial layer is non-distinctive); «presence of nodes» - «kind of stroma» (if nodes predominate, their histological structure is mainly represented by polymorphic clusters of synovitis cells in the form of cells, strands, chains, solid formations, among immature connective tissue with low hyalinosis); «cell size (area, cm²)» - «severity of haemosiderosis» and «cell size (area, cm²)» - «the number of multinucleated giant cells» (there is a pronounced deposition of pigment and accumulation of osteoclast-like multinucleated giant cells type, although usually their number is relatively small compared to the localized type of TSGCT). Conclusions: Morphological parameters, that we have identified, characterize pathological changes in the tissues of TSGCT; careful analysis of the frequency of their occurrence in the different comparison groups made it possible to establish intergroup differences and correlations between individual indicators, which were previously unknown or not obvious. Our study was determine to analyze of incidence rates and correlation relationships, revealed some previously unknown differences and dependencies that are important for understanding the pathogenesis, improvement of diagnosis and prognosis of diffuse-type TSGCT.


1993 ◽  
Author(s):  
Michael G. Brown ◽  
Frederick D. Tappert

1973 ◽  
Vol 54 (1) ◽  
pp. 305-306
Author(s):  
T. J. Schultz ◽  
P. W. Smith ◽  
C. I. Malme

2019 ◽  
Vol 101-B (3) ◽  
pp. 272-280 ◽  
Author(s):  
F. G. M. Verspoor ◽  
M. J. L. Mastboom ◽  
G. Hannink ◽  
W. T. A. van der Graaf ◽  
M. A. J. van de Sande ◽  
...  

Aims The aim of this study was to evaluate health-related quality of life (HRQoL) and joint function in tenosynovial giant cell tumour (TGCT) patients before and after surgical treatment. Patients and Methods This prospective cohort study run in two Dutch referral centres assessed patient-reported outcome measures (PROMs; 36-Item Short-Form Health Survey (SF-36), visual analogue scale (VAS) for pain, and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC)) in 359 consecutive patients with localized- and diffuse-type TGCT of large joints. Patients with recurrent disease (n = 121) and a wait-and-see policy (n = 32) were excluded. Collected data were analyzed at specified time intervals preoperatively (baseline) and/or postoperatively up to five years. Results A total of 206 TGCT patients, 108 localized- and 98 diffuse-type, were analyzed. Median age at diagnosis of localized- and diffuse-type was 41 years (interquartile range (IQR) 29 to 49) and 37 years (IQR 27 to 47), respectively. SF-36 analyses showed statistically significant and clinically relevant deteriorated preoperative and immediate postoperative scores compared with general Dutch population means, depending on subscale and TGCT subtype. After three to six months of follow-up, these scores improved to general population means and continued to be fairly stable over the following years. VAS scores, for both subtypes, showed no statistically significant or clinically relevant differences pre- or postoperatively. In diffuse-type patients, the improvement in median WOMAC score was statistically significant and clinically relevant preoperatively versus six to 24 months postoperatively, and remained up to five years’ follow-up. Conclusion Patients with TGCT report a better HRQoL and joint function after surgery. Pain scores, which vary hugely between patients and in patients over time, did not improve. A disease-specific PROM would help to decipher the impact of TGCT on patients’ daily life and functioning in more detail. Cite this article: Bone Joint J 2019;101-B:272–280.


2021 ◽  
Vol 20 ◽  
pp. 153303382110195
Author(s):  
Sang-Ho Jeong ◽  
Miyeong Park ◽  
Sun Yi Park ◽  
Jiho Park ◽  
Tae-Han Kim ◽  
...  

Introduction: There have been few studies about gene differences between patients with diffuse-type gastric cancer and those with intestinal-type gastric cancer. The aim of this study was to compare the transcriptomes of signet ring cell gastric cancer (worst prognosis in diffuse-type) and well-differentiated gastric cancer (best prognosis in intestinal-type); NUDC was identified, and its prognostic role was studied. Materials and Methods: We performed next-generation sequencing with 5 well-differentiated gastric cancers and 3 of signet ring cell gastric cancer surgical samples. We performed gene enrichment and functional annotation analysis using the Database for Annotation, Visualization and Integrated Discovery bioinformatics resources. Immunohistochemistry was used to validate NUDC expression. Results: Overall, 900 genes showed significantly higher expression, 644 genes showed lower expression in signet ring cell gastric cancer than in well-differentiated gastric cancers, and there was a large difference in adhesion, vascular development, and cell-to-cell junction components between the 2 subtypes. We performed variant analysis and found 52 variants and 30 cancer driver genes, including NUDC. We analyzed NUDC expression in gastric cancer tissue and its relationship with prognosis. Cox proportional hazard analysis identified T stage, N stage, and NUDC expression as independent risk factors for survival ( P < 0.05). The overall survival of the NUDC-positive group was significantly higher (53.2 ± 0.92 months) than that of the NUDC-negative group (44.6 ± 3.7 months) ( P = 0.001) in Kaplan-Meier survival analysis. Conclusion: We found 30 cancer driver gene candidates and found that the NUDC-positive group showed significantly better survival than the NUDC-negative group via variant analysis.


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