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Search Results: 1 - 10 of 319 matches for " mammography "
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Detection of Masses from Mammograms Using Mass shape Pattern
Aswini Kumar Mohanty,Mrs. Arati Pradhan,Mrs. Swasati Sahoo,Saroj Kumar Lenka
International Journal of Computer Technology and Applications , 2011,
Abstract: The purpose of this study was to develop a new method for automated mass detection in digital mammographic images using mass shape pattern. Masses were detected using a two steps process. First, the pixels in the mammogram images were scanned in 8 directions, and regions of interest (ROI) were identified using various thresholds. Then, a mass shape pattern was used to categorize the ROI as true masses or non-masses based on their morphologies. Each pixel of a ROI was scanned with a mass shape pattern to determine whether there was a shape (part of a ROI) similar to the mass in the shape pattern. The similarity was controlled using two thresholds. If a shape was detected, then the coordinates of the shape were recorded as part of a true mass.To test the system’s efficiency, we applied this process to 52 mammogram images from the Mammographic Image Analysis Society (MIAS) database. Three hundred and thirty-two ROI were identified using the ROI specification methods. These ROI were classified using three mass shape pattern whose diameters were 10, 20 and 30 pixels. The results of this experiment showed that using the mass shape pattern with these diameters achieved sensitivities of 93%, 90% and 81% with 1.3, 0.7 and 0.33 false positives per image respectively. These results indicate that the detection performance of this shape pattern based algorithm is satisfactory, and may improve the performance of computer-aided analysis of mammographic images and early diagnosis of mammographic masses.
Alternative Exposure Parameters and Post Process Noise Reduction Expect Considerable Dose Reduction in Single Mammography Views—Initial Experience on Mastectomy Specimens  [PDF]
Adriana M. J. Bluekens, Ruben Evan Engen, Nico Karssemeijer, Klaas H. Schuur, Mireille J. M. Broeders, Gerard J. den Heeten, Gerard J. den Heeten
Advances in Breast Cancer Research (ABCR) , 2013, DOI: 10.4236/abcr.2013.23016
Abstract:

Objective: To experimentally indicate a lower limit of dose in mammographic imaging yielding adequate image quality for complementary diagnostic views, by evaluation of image series with different exposure parameters and additional image processing on mastectomy specimens with diverse pathology. Methods: Image series were obtained on seven specimens with different target-filter combinations at different exposure values. Three experienced radiologists assessed the lowest acceptable dose level per specimen using a relative grading technique. With the standard image as reference, fibroglandular tissue and pathological structures, including microcalcifications, were evaluated. Subsequently, a series of pixel binning processes was tested and subjectively assessed on the selected images. Results: The lowest dose level at which image quality was acceptable, and achieved with a W/Ag target-filter combination at 32 kV and 4 mAs. These images can be acquired with 10.4% to 22.4% of the average glandular dose in standard images. Post process pixel binning added to the interpretability of such low dose images. Conclusion: This specimen study suggests that dose level of mammography images might be reduced substantially by general application of a W/Ag spectrum, particularly when combined with post process noise reduction. Future studies should focus on the feasibility of this technique in clinical mammography.

The Experience of Mammography Based on the Memoirs of Examinees  [PDF]
Mieko Uchiyama
Health (Health) , 2014, DOI: 10.4236/health.2014.611160
Abstract: The purpose of this study was to shed light on the pattern of the mammography experience from the examinee’s perspective based on episodic information extracted from notes written by the examinees. Using the notes is an effective approach to maintain privacy and avoid excessive stress. The study methods were qualitative inductive analyses of four sets of notes. Results showed that examinees “checked the words and actions of the medical staff” while relying on the “peace of mind instilled by the technician” before taking the mammogram. However, as breast compression became more intense, their feelings changed to a sense of “betrayal by someone on whom they were relying” since they felt that the technician was “ignoring the situation” or “considering but continuing breast compression”. They were also affected by the “shooting position which is impossible to avoid”. Breast compression during the mammography was a “pressure pain that exceeded their expectations” causing “dissatisfaction with the screening as a result of the pain” and “subconsciously created systemic tension”. Meanwhile, during the shooting, the examinees had performed “quiet countermeasures” such as “self-coping to distract themselves from the pain”. Examinees “earnestly desired a minimal shooting time” but, on the other hand, they also wanted “certainty of shooting rather than consideration of pain”. From these results, it is apparent that examinees were objectively observing the staff, even during shooting and the examinees were using self-coping measures to counter the pain. Providing support measures during mammography procedures is suggested based on the patterns of experiences.
?EXISTEN CANCERES NO DETECTABLES EN LA MAMOGRAFIA?
Horvath,Eleonora; Galleguillos,María Cecilia; Schonstedt,Valeria;
Revista chilena de radiología , 2007, DOI: 10.4067/S0717-93082007000200007
Abstract: women are greatly misinformed about the rate of false negatives found in mammography and tend to overestimate its sensitivity. this situation might create an increase in the number of lawsuits and demands of financial compensation. the frequency of mammographically occult cancers is estimated between 7 and 24%, depending on the evaluated population. these cancers are defined as those that have not been detected mammographically, but have been detected by other breast imaging methods such as ultrasound, magnetic resonance; by feeling or by the discovery of a metastasis. the small tumoral size, the absence of microcalci-fications and the low stromal reaction represent the histopathological characteristics responsible for the non-detectability especially in cases ofradiologically dense breasts, where the false negatives can reach up to 30%. the complementary breast us and the timely use of the breast mr significantly improve the detection rate. however some breast cancers are not represented on imaging, and are solely histopathological findings
Angiosarcoma of the Breast; Report of a Case and Literature Review
D. Farrokh,J. Hashemi,B. Zandi
Iranian Journal of Radiology , 2006,
Abstract: Angiosarcoma of the breast is a rare tumor that accounts for 0.04 % of all breast neoplasms at the third and fourth decades of life; in contrast with carcinoma, which generally arises later. Angiosarcoma of the breast usually manifests as a painless, palpable mass without tenderness, with or without bluish-red discoloration of the overlying skin. Angiosarcoma has a high mortality rate and a very poor prognosis. Mastectomy and chemotherapy are the most likely choices of treatment for a primary angiosarcoma of the breast. Immunotherapy may also play a part in treating this rare type of breast cancer. This paper presents a case of angiosarcoma of the breast, and relevant data in the literature is also reviewed to discuss the questions on its origin, symptoms, diagnosis and treatment.
Lossless compression of digital mammography using base switching method  [PDF]
Ravi kumar Mulemajalu, Shivaprakash Koliwad
Journal of Biomedical Science and Engineering (JBiSE) , 2009, DOI: 10.4236/jbise.2009.25049
Abstract: Mammography is a specific type of imaging that uses low-dose x-ray system to examine breasts. This is an efficient means of early detection of breast cancer. Archiving and retaining these data for at least three years is expensive, diffi-cult and requires sophisticated data compres-sion techniques. We propose a lossless com-pression method that makes use of the smoothness property of the images. In the first step, de-correlation of the given image is done using two efficient predictors. The two residue images are partitioned into non overlapping sub-images of size 4x4. At every instant one of the sub-images is selected and sent for coding. The sub-images with all zero pixels are identi-fied using one bit code. The remaining sub- images are coded by using base switching method. Special techniques are used to save the overhead information. Experimental results indicate an average compression ratio of 6.44 for the selected database.
Mucinous Carcinoma of the Breast Accompanied by Coarse Calcification  [PDF]
Hitomi Tani, Ryusuke Murakami, Tamiko Yoshida, Keiko Yanagihara, Shinya Iida, Shinichi Tsuchiya
Open Journal of Medical Imaging (OJMI) , 2012, DOI: 10.4236/ojmi.2012.24023
Abstract: Mucinous carcinoma of the breast has histologically distinct features and constitutes 1-3% of all breast cancers. It produces variable amounts of extracellular epithelial mucin and clinically its prognosis is far better than for other types of invasive carcinoma. On the other hand, coarse calcification is a common mammographic feature of benign tumors. There have been few reported cases of breast cancer containing coarse calcification. We present a unique 40 year-old female case of mucinous carcinoma of the breast accompanied by coarse calcification on mammography, which was mimicking fibroadenoma and an unusual variant of breast cancer. This case illustrates the importance of bearing in mind that mucinous carcinoma may demonstrate coarse calcification.
Effects of mammography positioning on the autonomic nervous function  [PDF]
Mieko Uchiyama, Yongbum Lee, Mieko Sadakata, Du-Yih Tsai, Mitsuko Sayama
Health (Health) , 2013, DOI: 10.4236/health.2013.58181
Abstract:

The physical and psychological burden on patients during mammography was analyzed using the autonomic function index in 34 adult females. The indices included heart rate (HR), high frequency (HF) of the R-R interval on an electrocardiogram, and the ratio of HF to LF (low frequency) (LF/HF). HR is an indicator of the degree of mental and physical activity, HF indicates the parasympathetic index and LF/HF indicates the sympathetic index. For the mediolateral oblique (MLO) view in mammography, autonomic function indices were measured before and during mammography. Statistical analysis was performed by the Mann-Whitney U test and the significance level was set at 5%. The autonomic function indices were compared before and during mammography and all showed no significant differences. The average value before imaging and the reference value at rest were compared. The results showed that HR increased 1.3-fold, HF increased 0.4-fold, and LF/HF increased 3.2-fold over reference values. Chronological changes during mammography showed that HF increased and LF/HF decreased from 120 seconds after the start of imaging. From these observations, it is evident that the state before mammography is not the same as the resting state and that the sympathetic index is dominant before imaging. They also suggest that some aspects of the psychological burden experienced during mammography are not due to the pain of breast compression alone.

An entity mimicking inflammatory breast carcinoma: Granulomatous mastitis  [PDF]
Nihal Uslu
Case Reports in Clinical Medicine (CRCM) , 2013, DOI: 10.4236/crcm.2013.24067
Abstract:

Granulomatous mastitis (GM) is a chronic inflammatory breast disease. This pathology was first described by Kersler and Wolloch in 1972 [1]. It is an uncommon cause of a breast mass [2-5]. Awareness of this entity is crucial, because it can clinically and radiologically mimic breast carcinoma, fibroadenoma or fibrocystic changes [3]. It has several appearances radiologically also; biopsy still remains the only way for final diagnoses. Here we present a woman with a breast mass. Our aim is to show ultrasound, mammography and magnetic resonance imaging findings of GM by reviewing the literature.

Evaluation of Breast Masses Using Mammography and Sonography as First Line Investigations  [PDF]
Kishor Taori, Suresh Dhakate, Jawahar Rathod, Anand Hatgaonkar, Amit Disawal, Prasad Wavare, Vishal Bakare, Rakhi P. Puri
Open Journal of Medical Imaging (OJMI) , 2013, DOI: 10.4236/ojmi.2013.31006
Abstract:

Purpose: To study the specificity of mammography and ultrasonography separately and in combination for detection of breast masses (ultrasonography-mammography correlation); To study the investigations to evaluate various breast masses; To describe suitable indications, advantages and limitations of each technique compared with other available modalities; To study the mimics of breast masses; To have histopathology follow-up and retrospective evaluation with imaging findings to improve diagnostic skills in series of 166 patients complaining of breast mass. Material: The prospective clinical study was carried out in the department of Radiodiagnosis for a period of 2 year extending from December 2010 to December 2012 infemale patients complaining of breast mass. Well informed written consent was obtained from them. Histopathology follow up was obtained from either biopsy or post operative tissue. USG machine: Philips HD 11 XE USG of the breasts and axillary region done in supine position in presence of female attendant; Mammography machine: Allengers machine with Agfa special mammography cassettes. Cranio caudal and Medio-Lateral Oblique views are taken in the presence of female attendant. MRI: PHILIPS 1.5 T machine; CT: SIEMENS duel slice CT machine. Results: Ultrasonography and mammography was done in most of the cases were sufficient to diagnose the lesion in most of the cases especially in benign breast masses. MRI and CT scan was used in special cases to know the extent of the lesions, in mimics of breast masses, bony extensions, primary muscular and bony lesions. Total 166 patients complaining of breast mass in one or both breasts were examined and evaluated with USG and mammography. The lesions were confirmed on histopathology (FNAC/biopsy). Out of 30 diagnosed malignancies two lesions were missed on mammography and four lesions were missed on ultrasonography. One of them was missed on both. For malignancies specificity of mammography is 93.3% and that of ultrasonography is 86.67%. Combining both the modalities specificity is near 97%.

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