000			11510nam a22002537a 4500
008			210111b2013 a|||f mb|| 00| 0 eng d
040			_aEG-CaNU _cEG-CaNU
041	0		_aeng _beng
082			_a610
100	0		_aEman Magdy Ahmed _9272
245	1		_aComputer-Aided Analysis of Fluorescein Angiograms Using Color Leakage Maps / _cEman Magdy Ahmed
260			_c2013
300			_a104 p. _bill. _c21 cm.
500			_3Supervisor: Ahmed Fahmy
502			_aThesis (M.A.)—Nile University, Egypt, 2013 .
504			_a"Includes bibliographical references"
505	0		_aContents: Chapter 1: INTRODUCTION ..................................................................................................... 1 1.1 Objectives ..................................................................................................................... 1 1.2 Motivation ..................................................................................................................... 2 1.3 Research Flow ............................................................................................................... 2 1.4 Datasets ......................................................................................................................... 3 1.5 Organization of thesis ................................................................................................... 4 Chapter 2: BACKGROUND ........................................................................................................ 5 2.1 Anatomy of Human Eye ............................................................................................... 5 2.1.1 Retina ................................................................................................................ 7 2.2 Retinal imaging ........................................................................................................... 10 2.2.1 Fundus Fluorescein Angiography ...................................................................... 10 2.2.1.1 Normal Fluorescein Angiograms ........................................................ 11 2.2.1.2 Abnormal Fluorescein Angiograms .................................................... 13 2.2.2 Optical Coherence Tomography ........................................................................ 16 2.2.2.1 Normal Optical Coherence Tomograms ............................................. 17 2.2.2.2 Abnormal Optical Coherence Tomograms ......................................... 18 2.3 Retinal Diseases .......................................................................................................... 19 2.3.1 Diabetic Macular Edema.................................................................................... 19 2.3.2 Age-related Macular Degeneration .................................................................... 21 2.4 Summary ..................................................................................................................... 25 Chapter 3: IMAGE PRE-PROCESSING ................................................................................. 27 3.1 Image Registration ...................................................................................................... 3.1.1 Literature Review............................................................................................ 27 3.1.2 Methodology ................................................................................................... 29 3.1.3 Implementation ............................................................................................... 31 3.1.4 Experiments .................................................................................................... 32 3.2 Vessel Removal .......................................................................................................... 33 3.2.1 Literature Review............................................................................................ 33 3.2.2 Methodology ................................................................................................... 33 3.2.3 Implementation ............................................................................................... 35 3.2.4 Experiments .................................................................................................... 37 3.3 Macula Cropping ........................................................................................................ 38 3.3.1 Methodology ................................................................................................... 38 3.3.2 Implementation ............................................................................................... 38 3.3.3 Experiments .................................................................................................... 39 3.4 Intensity Normalization .............................................................................................. 40 3.4.1 Methodology ................................................................................................... 40 3.4.2 Implementation ............................................................................................... 40 3.4.3 Experiments .................................................................................................... 41 3.5 Summary ..................................................................................................................... 42 Chapter 4: LESION ENHANCEMENT ................................................................................... 43 4.1 Modeling the Early Macula ........................................................................................ 43 4.1.1 Literature Review............................................................................................ 44 4.1.2 Methodology ................................................................................................... 45 4.1.3 Implementation ............................................................................................... 46 4.1.4 Experiments .................................................................................................... 48 4.2 Subtraction .................................................................................................................. 49 4.2.1 Methodology ................................................................................................... 49 4.2.2 Implementation ............................................................................................... 49 4.2.3 Experiments .................................................................................................... 50 4.3 Summary ..................................................................................................................... 52 Chapter 5: COLOR MAPPING ................................................................................................ 53 5.1 Simulating OCT line scans (Re-sampling) ................................................................. 5.1.1 Methodology ................................................................................................... 54 5.1.2 Implementation ............................................................................................... 54 5.1.3 Experiments .................................................................................................... 54 5.2 Simulating OCT image reconstruction ....................................................................... 55 5.2.1 Methodology ................................................................................................... 55 5.2.2 Implementation ............................................................................................... 56 5.2.3 Experiments .................................................................................................... 58 5.3 Mapping ...................................................................................................................... 59 5.3.1 Methodology ................................................................................................... 59 5.3.2 Implementation ............................................................................................... 60 5.3.3 Experiments .................................................................................................... 62 5.4 Summary ..................................................................................................................... 65 Chapter 6: RESULTS AND EVALUATION ........................................................................... 67 6.1 Results ......................................................................................................................... 67 6.2 Evaluation ................................................................................................................... 69 6.2.1 Correlation between FLM and OCT ............................................................... 69 6.2.2 Reproducibility of FLM .................................................................................. 72 Chapter 7: CONCLUSION AND FUTURE WORK ............................................................... 75 7.1 Conclusion .................................................................................................................. 75 7.2 Future Work ................................................................................................................
520	3		_aAbstract: Fundus Fluorescein Angiography (FFA) is a standard screening and diagnostic technique for several retinal diseases. FFA is powerful and essential for detecting and treatment-guiding of vascular-related retinal diseases such as diabetic retinopathy, macular edema, macular degeneration, retinal detachment, vascular occlusion, and tumors. Nevertheless, current analysis methods of FFA images depend on subjective evaluation of the amount of fluorescein leakage. This evaluation is qualitatively performed by skilled observers. Accordingly, these methods are vulnerable to inter-/intra-observer variability and lack accuracy and reproducibility as well. In this thesis, we present a new method for computer-aided analysis of FFA images. The method is based on generating objective color fluorescein leakage maps (FLM) that mimic the thickness maps produced by Optical Coherence Tomography (OCT). The generated FLM evaluates the fluorescein leakage and gives an indication about its severity. A complete system is introduced in this work to automatically generate FLM. It starts with pre-processing steps including: image registration, retinal blood vessels removal, cropping the macula and normalizing intensity between images. Then, modeling the early macula timeframes before subtracting it from late timeframes has been followed. Finally, simulating OCT image reconstruction has been presented to generate color FLMs. The proposed method was applied to 64 datasets of two different retinal diseases and the FLMs results were compared to the OCT thickness maps. The results show strong correlation between the FLMs and OCT thickness maps (r=0.8). The proposed method was found to be reproducible and robust to variability in the image acquisition times.
546			_aText in English, abstracts in English.
650		4	_aInformatics-IFM _9266
655		7	_2NULIB _aDissertation, Academic _9187
690			_aInformatics-IFM _9266
942			_2ddc _cTH
999			_c8797 _d8797