Biomedical subjects

C El Khoury

Publications and source records attributed to C El Khoury.

4 recordsLinked to original sources

PubMed2003

[CT and MR image fusion using two different methods after prostate brachytherapy: impact on post-implant dosimetric assessment].

PURPOSE: To study different methods of CT and MR images fusion in patient treated by brachytherapy for localized prostate cancer. To compare the results of the dosimetric study realized on CT slices and images fusion. MATERIALS AND METHODS: Fourteen cases of patients treated by I125 were retrospectively studied. The CT examinations were realized with contiguous section of 5mm thickness, and MR images were obtained with a surface coil with contiguous section of 3 mm thickness. For the images fusion process, only the T2 weighted MR sequence was used. Two processes of images fusion were realized for each patient, using as reference marks the bones of the pelvis and the implanted seeds. A quantitative and qualitative appreciation was made by the operators, for each patient and both methods of images fusion. The dosimetric study obtained by a dedicated software was realized on CT images and all types of images fusion. The usual dosimetric indexes (D90, V100 and V150) were compared for each type of image. RESULTS: The quantitative results given by the software of images fusion showed a superior accuracy to the one obtained by the pelvic bony reference marks. Conversely, qualitative and quantitative results obtained by the operators showed a better accuracy of the images fusion based on iodine seeds. For two patients out of three presenting a D90 inferior to 145 Gy on CT examination, the D90 was superior to this norm when the dosimetry was based on images fusion, whatever the method used. CONCLUSION: The images fusion method based on implanted seed matching seems to be more precise than the one using bony reference marks. The dosimetric study realized on images fusion could allow to rectify possible errors, mainly due to difficulties in surrounding prostate contour delimitation on CT images.

Adenocarcinoma↗

PubMed2003

[Interventional radiology in nonpalpable lesions of the breast].

The increasing number of nonpalpable breast lesions found at screening mammography has induced the development of percutaneous imaging-guided procedures to reduce the number of surgical biopsies. After a description of the indications (classification of the American College of Radiology), the different types of sampling procedures (fine needle aspiration, core and large-core biopsies) will be described and the material used also. Depending on the type of breast lesions (mass, clustered microcalcifications), ultrasound--guided and stereotactic--guided biopsies will be explained. Clear information to the patients, efficient quality control and multidisciplinary approach are mandatory for the success of these percutaneous diagnostic procedures.

Biopsy, Fine-Needle↗

PubMed2000

Diagnostic accuracy of sonography and combined sonographic assessment and sonographically guided cytology in nonpalpable solid breast lesions.

PURPOSE: The aim of this study was to assess the diagnostic accuracy of sonography alone and combined sonographic assessment and sonographically guided fine-needle aspiration cytology in solid, nonpalpable lesions of the breast. METHODS: We retrospectively evaluated the sonograms from a series of 174 consecutive nonpalpable masses that were cytologically diagnosed using fine-needle aspiration under sonographic guidance and then histologically verified through surgical excision. We examined the relationships between the findings from sonography, combined sonographic assessment and cytopathology, and histology. RESULTS: Histologically, 95 lesions (55%) were malignant and 79 (45%) were benign. The overall sensitivity of sonography alone for diagnosing cancer was 98. 9% (94 of 95 lesions), and the specificity was 45.6% (36 of 79 lesions). One (3%) of 37 masses considered at sonography to be benign was correctly diagnosed on cytologic examination to be cancer. By establishing the benign status of 11 of 13 masses that were indeterminate at sonography, cytology increased the specificity of the combined method (to 56.3%). Cytology appropriately suspected or confirmed malignancy in 79 (84%) of 94 carcinomas considered at sonography to be suspicious or malignant. CONCLUSIONS: In this study, sonography alone demonstrated a high sensitivity but limited specificity in evaluating nonpalpable breast masses. The addition of sonographically guided cytology substantially increased the specificity of the combined method without compromising sensitivity.

Adult↗

PubMed2000

Colloid cysts of the third ventricle: are MR imaging patterns predictive of difficulty with percutaneous treatment?

BACKGROUND AND PURPOSE: Colloid cysts of the third ventricle are rare benign brain tumors. The purpose of this study was to correlate their patterns on MR images with the probability of success of percutaneous treatment. METHODS: Nineteen patients underwent endoscopic treatment for colloid cysts of the third ventricle. The cases were divided into two groups based on difficulty of the aspiration procedure. We reviewed CT scans and MR images and divided cysts into groups based on their signal intensity on the MR images and their density on CT scans. Intensity and density were correlated with difficulty of aspiration during the endoscopic procedure. RESULTS: The aspiration procedure was difficult in 63% of the cases. Eighty-nine percent of hyperdense cysts on unenhanced axial CT scans were categorized as difficult, and 75% of hypodense cysts were categorized as easy. On T2-weighted MR sequences, 100% of low-signal cyst contents were difficult and nearly 63% of high-signal lesions were easy. There was a significant correlation between the T2-weighted sequences and the CT scans regarding the difficulty of the aspiration procedure. CONCLUSION: T2-weighted MR sequences are useful for predicting difficulty of aspiration during stereotactic or endoscopic procedures. A T2-weighted low-signal cyst is correlated with high-viscosity intracystic contents.

Adult↗