The impact of simulated motion blur on breast cancer detection performance in full field digital mammography (FFDM)

Objective: Full-field Digital Mammography (FFDM) is employed in breast screening for the early detection of breast cancer. High quality, artefact free, diagnostic images are crucial to the accuracy of this process. Unwanted motion during the image acquisition phase and subsequent image blurring is an unfortunate occurrence in some FFDM images. The research detailed in this thesis seeks to understand the impact of motion blur on cancer detection performance in FFDM images using novel software to perform simulation of motion, an observer study to measure the lesion detection performance and physical measures to assess the impact of simulated motion blur on image characteristics of the lesions. Method: Seven observers (15±5 years’ reporting experience) evaluated 248 cases (62 containing malignant masses, 62 containing malignant microcalcifications and 124 normal cases) for three conditions: no motion blur (0.0 mm) and two magnitudes of simulated motion blur (0.7 mm and 1.5 mm). Abnormal cases were biopsy proven. A free-response observer study was conducted to compare lesion detection performance for the three conditions. Equally weighted jackknife alternative free-response receiver operating characteristic (wJAFROC) was used as the figure of merit. A secondary analysis of data was deemed important to simulate ‘double reporting’. In this secondary analysis, six of the observers are combined with the seventh observer to evaluate the impact of combined free-response data for lesion detection and to assess if combined two observers data could reduce the impact of simulated motion blur on detection performance. To compliment this, the physical characteristics of the lesions were obtained under the three conditions in order to assess any change in characteristics of the lesions when blur is present in the image. The impact of simulated motion blur on physical characteristics of malignant masses was assessed using a conspicuity index; for microcalcifications, a new novel metric, known as dispersion index, was used. Results: wJAFROC analysis found a statistically significant difference in lesion detection performance for both masses (F (2,22) = 6.01, P=0.0084) and microcalcifications (F(2,49) = 23.14, P<0.0001). For both lesion types, the figure of merit reduced as the magnitude of simulated motion blur increased. Statistical differences were found between some of the pairs investigated for the detection of masses (0.0mm v 0.7mm, and 0.0mm v 1.5mm) and all pairs for microcalcifications (0.0 mm v 0.7 mm, 0.0 mm v 1.5 mm, and 0.7 mm v 1.5 mm). No difference was detected between 0.7 mm and 1.5 mm for masses. For combined two observers’ data of masses, there was no statistically significant difference between single and combined free-response data for masses (F(1,6) = 4.04, p=0.1001, -0.031 (-0.070, 0.008) [treatment difference (95% CI)]. For combined data of microcalcifications, there was a statistically significant difference between single and combined free-response data (F(1,6) = 12.28, p=0.0122, -0.056 (-0.095, -0.017) [treatment difference (95% CI)]. Regarding the physical measures of masses, conspicuity index increases as the magnitude of simulated motion blur increases. Statistically significant differences were demonstrated for 0.0–0.7 mm t(22)=-6.158 (p<0.000); 0.0–1.5 mm t(22)=-6.273 (p<0.000); and 0.7–1.5 mm (t(22)=-6.231 (p<0.000). Lesion edge angle decreases as the magnitude of simulated motion blur increases. Statistically significant differences were demonstrated for 0.0–0.7 mm t(22)=3.232 (p<0.004); for 0.0–1.5 mm t(22)=6.592 (p<0.000); and 0.7–1.5mm t(22)=2.234 (p<0.036). For the grey level change there was no statistically significant difference as simulated motion blur increases to 0.7 and then to 1.5mm. For image noise there was a statistically significant difference, where noise reduced as simulated motion blur increased: 0.0–0.7 mm t(22)=22.95 (p<0.000); 0.0–1.5mm t(22)=24.66 (p<0.000); 0.7–1.5 mm t(22)=18.11 (p<0.000). For microcalcifications, simulated motion blur had a negative impact on the ‘dispersion index’. Conclusion: Mathematical simulations of motion blur resulted in a statistically significant reduction in lesion detection performance. This reduction in performance could have implications for clinical practice. Simulated motion blur has a negative impact on the edge angle of breast masses and a negative impact on the image characteristics of microcalcifications. These changes in the image lesion characteristics appear to have a negative effect on the visual identification of breast cancer

The impact of simulated motion blur on lesion detection performance in full field digital mammography

Objective: Motion blur is a known phenomenon in full-field digital mammography, but the impact on lesion detection is unknown. This is the first study to investigate detection performance with varying magnitudes of simulated motion blur. Method: Seven observers (15±5 years’ reporting experience) evaluated 248 cases (62 containing malignant masses, 62 containing malignant microcalcifications and 124 normal cases) for three conditions: no blurring (0 mm) and two magnitudes of simulated blurring (0.7 mm and 1.5 mm). Abnormal cases were biopsy proven. Mathematical simulation was used to provide a pixel shift in order to simulate motion blur. A free-response observer study was conducted to compare lesion detection performance for the three conditions. The equally weighted jackknife alternative free-response receiver operating characteristic (wJAFROC) was used as the figure of merit. Test alpha was set at 0.05 to control probability of Type I error. Results: wJAFROC analysis found a statistically significant difference in lesion detection performance for both masses (F(2,22) = 6.01, P=0.0084) and microcalcifications (F(2,49) = 23.14, P<0.0001). The figures of merit reduced as the magnitude of simulated blurring increased. Statistical differences were found between some of the pairs investigated for the detection of masses (0.0mm v 0.7mm, and 0.0mm v 1.5mm) and all pairs for microcalcifications (0.0 mm v 0.7 mm, 0.0 mm v 1.5 mm, and 0.7 mm v 1.5 mm). No difference was detected between 0.7 mm and 1.5 mm for masses. Conclusion: Mathematical simulation of motion blur caused a statistically significant reduction in lesion detection performance. These false negative decisions could have implications for clinical practice. Advances in knowledge: This research demonstrates for the first time that motion blur has a negative and statistically significant impact on lesion detection performance digital mammography

Pengungkapan Corporate Social Responsibility (CSR) Pada Bank Konvensional Di Indonesia

Setiap perusahaan didirikan adalah untuk jangka panjang dan berharap selalu bisa berkembang dalam setiap periode, maka dari itu perusahaan harus memperhatikan pihak-pihak yang berkepentingan dengan perusahaan demi keberlangsungan perusahaan itu sendiri. Corporate Social Responsibility (CSR) adalah sebuah konsep yang mana menjelaskan bahwa sebuah perusahaan mempunyai sebuah tanggung jawab tidak hanya terhadap lingkungan yang berada dalam kegiatan operasional perusahaan saja, akan tetapi juga mempunyai tanggung jawab terhadap konsumen, karyawan, pemegang saham, dan komunitas. Populasi penelitian ini adalah seluruh perbankan konvensional yang go public dan terdaftar pada Bank Indonesia dengan laporan keuangan tahun 2009-2011. Adapun sampel yang digunakan adalah bank besar yang memiliki total aktiva sebesar (total aktiva yang dimiliki Rp.1 - Rp.10 trillion ($117 -$1.17 billion) yang mana terdiri dari 7 bank yaitu Bank Mandiri, Bank Rakyat Indonesia, Bank Danamon, Bank CIMB Niaga, Bank Central Asia, Bank Panin dan Bank Negara Indonesia 46. Penelitian ini dihitung menggunakan indeks Global Report Initiative (GRI) yang terdiri dari 121 item pengungkapan. Dalam penelitian ini terlihat bahwa setiap bank melakukan kegiatan CSR pada bank konvensional lebih terfokus pada aspek pendidikan dan sosial yang mana lebih tertuju kepada masyarakat dan lingkungan

Üniversite Öğrencilerinin Geri Dönüşüm Bilinci Üzerine Bir Araştırma: Sakarya Üniversitesi Örneği

Bu çalışmanın amacı üniversite öğrencilerinin geri dönüşüm farkındalığı ve algısını tespit etmektir. Bu amaçla sosyal bilimlerde sıklıkla kullanılan anket yönteminden yararlanılmıştır. Çalışmanın evreninin Türkiye’deki tüm üniversite öğrencilerinin olduğu çalışmada evrenin tamamına ulaşmanın kısıtlı zaman ve yüksek maliyet nedeniyle mümkün olmaması dolayısıyla, anket kartopu örnekleme yöntemi ile yalnızca Sakarya üniversitesi öğrencilerine uygulanmıştır. Araştırma sorusu “Üniversitesi öğrencilerinin geri dönüşüme yönelik davranışları nasıldır? olan çalışmada üniversite öğrencilerinin geri dönüşüm algısı ve geri dönüşüm davranışları belirlenmeye çalışılmıştır. Araştırmanın ilk bölümünde geri dönüşüm ile ilgili kavramsal çerçeveye ikinci bölümünde geri dönüşüm ile ilgili uygulamalı literatür ve sonuçlarına, üçüncü bölümünde ise üniversite öğrencilerinin geri dönüşüm davranışlarına ilişkin Sakarya özelinde yapılmış saha araştırması sonuçlarına yer verilmiştir. Sonuç ve değerlendirme bölümünde araştırma sonucunda elde edilen bulgular sunulmuş ve değerlendirilmiştir

Deteksi Antibodi terhadap Virus Newcastle Disease pada Burung Trucukan (Pycnonotus goiavier)

Burung trucukan (Pycnonotus goiavier) merupakan salah satu burung liar yang sering dipelihara karena kicauannyayang merdu. Infeksi ND dapat berupa infeksi yang akut atau kronis yang menyerang burung trucukan dan jenis burunglainnya. Burung liar merupakan salah satu sumber virus ND yang dapat menyebarkan virus ke unggas peliharaan.Penelitian ini bertujuan untuk mengetahui titer antibodi terhadap penyakit tetelo pada burung trucukan liar. Sampel yangdigunakan adalah serum darah dari 50 ekor burung trucukan liar. Parameter yang diamati adalah titer antibodi dalamserum berdasarkan metode Hirst menggunakan uji Haemagglutination Inhibition (HI) untuk melihat titer antibodi. Untukmenghitung titer virus maka uji Haemaglutination (HA) dilakukan sebelumnya. Untuk memastikan titer antigen yangdigunakan adalah 4HAU dilkukan juga back titrasi sehingga didapatkan nilai virus optimal yang akan dipakai pada uji HI.Hasil penelitian menunjukkan 45 dari 50 sampel (90%) mempunyai antibodi positif terhadap ND, dengan titer berkisar 21-29. Berdasarkan hasil yang diperoleh dapat disimpulkan bahwa 90% burung trucukan di Kabupaten Aceh Besar sudahpernah terpapar ND, tetapi hanya 80% yang memiliki titer antibodi yang dapat melingdungi terhadap serangan virus ND.Oleh sebab itu dapat disimpulkan bahwa burung trucukan liar dengan titer antibodi yang protektif berarti sudah pernahterpapar virus ND sebelumnya akan berpotensi sebagai pembawa virus yang dapat ditularkan ke unggas peliharaanmasyarakat di sekitarnya

Anatomical variations of the lumbrical muscles causing carpal tunnel syndrome

Many anatomical variations exist in and around the carpal tunnel. However, symptomatic anomalies causing carpal tunnel syndrome is rare. Additionally, carpal tunnel surgery is considered a simple operation commonly done by junior surgeons who are usually unaware of variations resulting in unfavorable surgical outcomes. We highlight a case of lumbrical muscle variation causing carpal tunnel syndrome. A 73-year-old male presented with numbness and pain of both hands associated with abnormal fullness over both wrists and distal forearms. Initially the right hand was numb and subsequently a year later, the left hand became numb. Physical examination was positive for Durkan, Phalen and Tinel signs at the carpal tunnel. Magnetic Resonance Imaging (MRI) showed abnormal muscle tissues in the carpal tunnel. During the carpal tunnel release and exploratory surgery, we noted an abnormally proximal origin of the lumbrical muscles in the forearm rather than the typical palmar origin. He also had lumbrical muscle hypertrophy in the left side. These two factors resulted in overcrowding within the carpal tunnel. Post-operatively the patient recovered well with pain relief and gradual improvement of his numbness. Variations in the anatomy of the lumbrical muscles is not uncommon and may result in carpal tunnel syndrome. Hence, carpal tunnel release surgeries may not be as straight forward as expected and surgeons should be aware of this possibility

Addressing triggering post zancolli lasso procedure

A claw hand causes disability as kinematics are affected due to hyperextension at the metacarpophalangeal joints. Zancolli lasso procedure is a simple tenodesis procedure which effectively lessens clawing to allow better grip. We present a56-year-old lady who had a history of trauma with progressive clawing of her left hand. She has been diagnosed with partially recovered incomplete lower trunk brachial plexus injury. She underwent successful Zancolli lasso procedures for all of her fingers but 8 months later, the patient developed triggering of the index and middle fingers. We experimented by releasing the adhesions in one finger and releasing the whole A1 pulley together with the lasso-ed flexor digitorum superficialis (FDS) in the other finger and the latter worked.We repeated the procedure in the index finger and the triggering resolved. Although both her index and middle fingers now have a flexor digitorum profundus (FDP) only (the FDS having retracted proximally), she did not have a recurrence of her clawing. We attributed the triggering due to increasing A1 pulley volume as well as contractures causing post-release functional positions

A black finger does not equal a dead finger

Revascularisation and replant surgery occasionally produces sub-optimal results. We present two cases of near total amputation of the digits. The first patient was an 11-year-old boy with a middle finger avulsion injury sustained after the finger was caught in a washing machine with the flexor digitorum profundus still attached. The second patient was a 42-year-old male who sustained a machete attack and had near total amputation of his small and ring fingers with a 2 cm skin bridge still attached. All patients underwent revascularization with repair of only one digital artery for each finger as the opposite artery was non-viable. No digital veins were repaired. Relief of venous congestion was done by pin-prick six times a day up till one week. At one week post-surgery, the fingers were discoloured black but had good pulp turgor and full contour with arterial bleed on pin-prick. Inexperienced surgeons may view this as gangrene and amputate the fingers. However, we continued observation and at one month post-surgery, the black skin had desloughed and the underlying skin was pink