Daphné Wallach

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BACKGROUND Accurate needle placement is crucial for the success of percutaneous radiological needle interventions. We compared three guiding methods using an optical-based navigation system: freehand, using a stereotactic aiming device and active depth control, and using a stereotactic aiming device and passive depth control. METHODS For each method, 25(More)
Respiratory motion is a major source of reduced quality in positron emission tomography (PET). In order to minimize its effects, the use of respiratory synchronized acquisitions, leading to gated frames, has been suggested. Such frames, however, are of low signal-to-noise ratio (SNR) as they contain reduced statistics. Super-resolution (SR) techniques make(More)
OBJECTIVE Angiographic C-arm CT may allow performing percutaneous stereotactic tumor ablations in the interventional radiology suite. Our purpose was to evaluate the accuracy of using C-arm CT for single and multimodality image fusions and to compare the targeting accuracy of liver lesions with the reference standard of MDCT. MATERIALS AND METHODS C-arm(More)
Images from computed tomography (CT), combined with navigation systems, improve the outcomes of local thermal therapies that are dependent on accurate probe placement. Although the usage of CT is desired, its availability for time-consuming radiological interventions is limited. Alternatively, three-dimensional images from C-arm cone-beam CT (CBCT) can be(More)
Accurate definition of single marker (SM) locations in computed tomography (CT) images is a part of the patient-toimage registration technique used in our navigation system for interventional radiology. The SMs are currently selected manually by the user. We herein present a two-step image processing algorithm first uses morphological operations on the(More)
Purpose Liver cancer is the 5 most common cancer and shows poor prognosis. Surgical removal of liver tumours, the only existing curative treatment, can merely be used in 10-20% of the case. Increasing surgical precision is a key-challenge to give more patients access to a potentially curative treatment. Recent progress in computer science enables the use of(More)
In this retrospective epidemiological study, records from the Contact Lens Department of SUNY College of Optometry were randomly selected and reviewed. An association between contact lens induced giant papillary conjunctivitis (GPC) and a FDA classified sub-category was found. Younger patients were shown to have a higher risk of developing GPC. Gender and(More)
The interest of PET complementary information for the delineation of the target volume in radiotherapy of lung cancer is increasing. However, respiratory motion requires the determination of a functional internal target volume (ITV) on PET images for which several strategies have been proposed. The purpose of this study was the comparison of these(More)
A dual algorithm for problems of Fourier Synthesis is proposed. Partially finite convex programming provides tools for a formulation which enables to elude static pixelization of the object to be reconstructed. This leads to a regularized reconstruction-interpolation formula for problems in which finitely many and possibly irregularly spaced samples of the(More)
Stereotactic navigation is usually based on rigid registration of the intraoperative situation with preoperatively acquired images. Under this assumption, soft tissue deformation and patient motion will affect the guidance information provided by optical navigation system and can add significant inaccuracy depending on the amount of target motion relative(More)