Faculty Bibliography

It is shown that the two-by-two Jones-matrix formalism for polarization optics is a six-parameter two-by-two representation of the Lorentz group. The attenuation and phase- shift filters are represented, respectively, by the three- parameter rotation subgroup and the three-parameter Lorentz group for two spatial dimensions and one time dimension. The Lorentz group has another three-parameter subgroup, which is like the two-dimensional Euclidean group. Optical filters that may have this Euclidean symmetry are discussed in detail. It is shown that the Jones-matrix formalism can be extended to some of the nonorthogonal polarization coordinate systems within the framework of the Lorentz-group representation. (C) 1997 Optical Society of America

BrE-3 is a murine IgG1 monoclonal antibody that binds to 97% of human ductal breast cancer specimens. A previous study documented the ability of 111In-labeled 1,4-methyl-benzyl isothiocyanate diethylenetriamine pentaacetic acid (111In-MX-DTPA) BrE-3 to specifically target breast cancer tissue in patients, and the dosimetry derived from the pharmacokinetics suggested that a useful therapeutic index could be obtained with 90Y-MX-DTPA BrE-3. A Phase I maximum tolerated dose study was, therefore, initiated. METHODS: Six patients received 111In/90Y-MX-DTPA BrE-3, three of them receiving 6.25 and the other three receiving 9.25 mCi/m2 of 90Y. Pharmacokinetics, dosimetry, human anti-mouse antibody (HAMA), toxicity and clinical responses were evaluated. RESULTS: Three of six patients demonstrated a minor and transient, but objective tumor response, and none of the patients had significant toxicity. Tumor dosimetry ranged from 39 to 167 rad/mCi of 90Y (442-1887 rad/ dose). HAMA response occurred in five of six patients. CONCLUSION: Minimal toxicity, dosimetric calculations and clinical assessment indicate that a useful therapeutic index can be achieved with this therapy. Indium-111/yttrium-90-MX-DTPA BrE-3 can be safely administered to patients with metastatic breast cancer, and therapy doses yielded pharmacokinetics similar to those of tracer doses. Clinical responses, albeit transient, were achieved with single-dose therapy. Rapid onset of the HAMA response will hinder multicycle therapy, unless it is prevented with immunosuppressive drugs or the use of a 'humanized' antibody. Further studies are needed to determine the optimal use of BrE-3 for radioimmunotherapy

We present a graphical three-dimensional method that facilitates image registration and fusion, and provides quantitative geometric and volume information. In particular it enhances the use of functional (radiopharmaceutical) imaging (SPECT, PET) which, though a powerful clinical tool, has the disadvantage of low spatial resolution and ill-defined boundaries. Registration between functional images and structural images (MRI, CT) can augment the anatomical context of these functional images

This paper describes a cost-effective technique that optimally utilizes all available diagnostic studies for three-dimensional treatment planning. A simulator unit modified to produce cross-sectional images (simulator-CT unit) is used to create a reference data set with the patient in the treatment position. Registration software (qsh) brings other diagnostic studies into agreement with this reference data set. Two cases are presented as examples of the use of this technique. Registration of abdominal scans from the same patient demonstrates the warping of a nontreatment position study to the treatment position. The second case is based on paired data sets through the head, in which the diagnostic study was obtained by using a gantry tilt to follow the base of the skull and to avoid sections passing through the teeth. The registration software provides a method for combining diagnostic studies into a single 'master' data set. The success of the transformation depends on the operator's ability to identify corresponding anatomic landmarks for different data sets and on the magnitude of the variation in the patient's position from one procedure to the next. Limitations in image quality and the number of cross-sections obtainable from a simulator-CT unit can be partially overcome by using the described technique. Thus, the information contained in nontreatment position diagnostic tests can be used accurately for treatment planning at limited cost

It is shown that the bilinear representation of the Lorentz group is the natural language for the polarization of light. The combined effect of attenuation and phase-shift filters leads to a two-by-two representation of the Lorentz group, which can then be translated into the bilinear representation. The coherency matrix is a representation of the six-parameter Lorentz group

Plagiocephaly is a term commonly used to describe congenital forehead asymmetry. Previous classification systems based on the various etiologies of dysmorphic crania have been used in an effort to categorize the patients into groups and to assist in treatment planning. The system most commonly used today was described by Bruneteau and Mulliken in 1992. The authors separated frontal plagiocephaly into three types: synostotic, compensational, and deformational. The present study was undertaken in order to define a simple system for classifying plagiocephaly based on Bruneteau and Mulliken's system using the patients' preoperative craniofacial computed tomography scans. The involvement of the entire coronal ring in synostotic plagiocephaly led to the choice of 20 skull base landmarks as the basis of the analysis. Nine lateral landmarks (the superior orbital fissure, the optic foramen, the zygomatic arch, the greater palatine foramen, the foramen ovale, the mastoid tip, the hypoglossal canal, the external auditory canal, and the internal auditory canal) and two midline landmarks (the crista galli and the internal occipital protuberance) were used. The changes that occurred in these landmarks were analyzed in 30 patients. The results demonstrated that Bruneteau and Mulliken's classification system underestimated the number of different subtypes of plagiocephaly. As a result, three major types of frontal plagiocephaly and several different subtypes based on the different etiologies were described. Type I plagiocephaly includes plagiocephaly resulting from cranial suture synostosis. Type II includes those with a nonsynostotic etiology. Type III describes patients with craniofacial microsomia-associated plagiocephaly. Statistical analysis was unavailable because of the small number of patients in each subtype. With a larger number of patients, we hope to refine this system for use by the surgeon in preoperative diagnosis and surgical planning. The analysis is unique in its ability to quantitate changes from normal on the x-, y-, and z-coordinates, and therefore allows for identification of both horizontal (frontal bone deviation) and vertical (ear shear) growth disturbances

In non-small cell lung cancer (NSCLC), accurate staging is critical in deciding between potentially curative surgery and palliative treatment. Image registration, or fusion, combines the unique functional information provided by SPECT imaging with the excellent anatomic detail offered by computed tomography (CT) or magnetic resonance imaging to better characterize the information provided by each separate modality. In this study, we explored the role of fusion of immunoscintigraphy SPECT with CT in the staging of NSCLC. We fused chest CT with 99mTc-labeled IMMU-4 anti-carcinoembryonic antigen Fab\' antibody fragment SPECT in 14 patients with NSCLC using a landmark-based algorithm. The algorithm\'s accuracy was a measure from the center-to-center distance and the percentage overlap of two regions of interest: one drawn on CT and warped onto SPECT, the other drawn directly on the SPECT. We found that the average center-to-center distance was 1.3 +/- 0.8 pixels. Average overlap was 46 +/- 20%. CT-SPECT fusion helped differentiate tumor from normal blood pool, necrotic areas within viable tumor, tumor recurrence from scar, and malignant lymphadenopathy from hyperplasia. We conclude that fusion of CT and SPECT augments the information provided by each separate modality. Future clinical applications of fusion in NSCLC staging using immunoscintigraphy appear promising

Within the wavelet framework, it is shown that it is possible to construct a Lorentz-covariant superposition of light waves. The concept of window allows the definition of a ''finite difference'' between wavelets and photons. It is pointed out that a windowed function is as accurate as any continuous function which may be constructed from a discrete set of experimental data

In classical mechanics, the system of two coupled harmonic oscillators is shown to possess the symmetry of the Lorentz group O(3,3) or SL(4,r) in the four-dimensional phase space. In quantum mechanics, the symmetry is reduced to that of O(3,2) or Sp(4), which is a subgroup of O(3,3) or SL(4,r), respectively. It is shown that among the six Sp(4)-like subgroups, only one possesses the symmetry which can be translated into the group of unitary transformations in quantum mechanics. (C) 1995 American Institute of Physics