A new optical method, for the assessment of the optic nerve-head topography, was studied theoretically and experimentally. The motivation of this work is in relation with glaucoma, an eye disease that can lead to blindness. Glaucoma manifests itself by a destruction (atrophy) of the retinal axons, which in turn affects the shape (topography) of the optic nerve head (disc). Topographic measurement of the optic nerve head is used for diagnosis and tracking (progression) of glaucoma. The new technique consists of a dual-fringe projection system and a single-view imaging system. The dual-fringe projection system produces a 3-D irradiance distribution in the measurement volume (optic nerve location) and the modulation of the fringes is used to profile the optic nerve head. Since the optic nerve disc is optically accessible only through the ocular media, the new method is conceived to access the optic nerve through the eye pupil and to minimize the effects of ocular variations such as the optical power and third order aberrations of the eye. The method can use a low power broad-band source and is therefore safe for the eye. Two prototypes were built (coherent and incoherent source) and evaluated using an optical system that simulates the eye. The new method can be applied to the topographic measurement of any diffuse object, whether it is directly accessible or not.

The development and verification of thermal models for use in hyperthermia treatment planning is essential for obtaining accurate predictions of temperature fields. This thesis presents a three-dimensional blood vessel network constructed from connected straightline segments. The geometry of this convective thermal model is an (approximate) cube. The model contains seven levels of different size arterial vessels. The calculations of the mean blood temperature inside the vessels are based on the convective energy balance equation for the bulk fluid temperature. The adjacent tissue temperature calculations are based on either pure conduction heat transfer or the bioheat transfer equation of Pennes (22). The validity of the convective thermal model is checked by comparing it's predictions to those of an analytical solution for a single vessel, and by checking the energy balance calculations of the whole control volume. The results show that the level-7 arteries still contribute a large percentage of the total heat transfer rate between the blood vessels and the surrounding tissues; and values of the Nusselt number being either 10% higher or 10% lower than 4 do not strongly affect the temperature field.

The objective of this thesis is to investigate how the human Electroencephalogram(EEG) is affected by anesthetic agents. The ultimate goal of the research is to improve clinical understanding of the EEG in anesthesia, and to determine the value of quantitative analytical techniques for generalizing or differentiating among anesthetic agents. Power spectrum and time domain analysis were conducted on EEG waveforms from 30 human, male volunteer subjects during sevoflurane and enflurane general anesthesia. Univariate parametric statistics and Discriminant Function Analysis (DFA) were performed to analyze and classify EEG spectral content. Statistically significant differences were found between the two anesthetics, duration of anesthetic period, and anesthetic depth levels. DFA classification of EEG epochs by anesthetic condition group was performed with a high degree of accuracy, especially when the stepwise analysis method was used.

The anatomy and physiology of the human heart, the historical development of heart transplantation and mechanical assistance, and total artificial heart and ventricular assist device systems are discussed. The focus of the investigation is on the detection of waveform indicators corresponding to full-filling of the artificial heart and ventricular assist device chambers. The developed software monitors the drive pressure waveform produced by the circulatory assist system until a full-fill indicator is detected. The event is verified by the detection of a corresponding indication during the same period within the flow waveform of the circulatory assist system. The appropriate alarm (for the right or left chamber) is updated each time a full-fill event is verified. When the user specified alarm limit is reached, an entry describing the alarm event is entered into the patient data file and a +5 volt analog signal is made available for external alarm activation.

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