Biomedical subjects

Leslie E Quint

Publications and source records attributed to Leslie E Quint.

7 recordsLinked to original sources

PubMed2006

CT-guided thoracic core biopsies: value of a negative result.

Previous studies have reported low negative predictive values (NPV) for computed tomography (CT)-guided fine needle aspiration of lung nodules in excluding malignancy. Our aim was to determine the NPV of transthoracic core needle biopsy in a tertiary care hospital with a large cancer patient population. The results of 226 consecutive CT-guided transthoracic core needle biopsies were reviewed. Results were classified into one of the following four groups: positive or suspicious for malignancy, benign specific, benign non-specific, and non-diagnostic. The benign specific group included entities such as fungus, hamartoma and schwannoma. In the benign non-specific group, histologic findings such as scar and inflammation were reported. The non-diagnostic group included cases with only normal pulmonary tissue in the specimen and/or insufficient tissue to render any diagnosis. The results were correlated with subsequent proof obtained via surgery or clinical and imaging follow-up. Out of a total of 226 biopsies, 158 were positive or suspicious for malignancy, 8 were benign specific, 32 were benign non-specific and 28 were non-diagnostic. Forty-three benign non-specific or non-diagnostic cases had subsequent proof, and malignancy was subsequently confirmed in 16/43 cases (5/21 non-specific and 11/22 non-diagnostic cases). The NPVs were 76% and 50% for benign non-specific and non-diagnostic biopsies, respectively. The overall NPV and false negative rate were 68% and 9%, respectively. A core biopsy revealing non-specific benign tissue or insufficient tissue for diagnosis is unreliable in excluding malignancy, and patients with these types of biopsy results should have resampling of tissue or close clinical and imaging follow-up.

Biopsy, Fine-Needle↗

PubMed2006

PET: other thoracic malignancies.

The vast majority of esophageal cancers are fluorodeoxyglucose (FDG) avid; the primary use for positron emission tomography (PET) in patients with esophageal cancer is in the detection of distant metastases, because known distant metastatic disease precludes surgical resection. High standardized uptake values (SUVs) may be predictive of poor prognosis. PET findings may be used to assess therapy response and evaluate for esophageal tumor recurrence after treatment. PET findings may be non-specific in different types of thymic lesions, although thymic carcinomas tend to be extremely FDG avid. PET can be helpful in detecting distant spread from invasive thymomas and thymic carcinomas. Similarly, PET may be used to assess the extent of disease in patients with malignant pleural mesothelioma, thereby facilitating optimal therapy approaches.

Carcinoma↗

PubMed2005

Imaging of thymic disorders.

Evaluation of the thymus poses a challenge to the radiologist. In addition to age-related changes in thymic size, shape, and tissue composition, there is considerable variability in the normal adult thymic appearance within any age group. Many different types of disorders may affect the thymus, including hyperplasia, cysts, and benign and malignant neoplasms, both primary and secondary; clinical and imaging findings typical for each disease process are described in this article. Whereas computed tomography is the mainstay for imaging the thymus, other imaging modalities may occasionally provide additional structural or functional information.

Diagnostic Imaging↗

PubMed2005

CT-based definition of thoracic lymph node stations: an atlas from the University of Michigan.

PURPOSE: Accurate delineation of the mediastinal and hilar lymph node regions is essential for a reproducible definition of target volumes used in conformal irradiation of non-small-cell lung cancer. The goal of this work was to generate a consensus to delineate these nodal regions based on definitions from the American Joint Committee on Cancer. METHODS AND MATERIALS: A dedicated thoracic radiologist, thoracic surgeon, medical physicist, and three radiation oncologists were gathered to generate a three-dimensional radiologic description for the mediastinal and hilar nodal regions on axial CT scans. This paper proposes an atlas of most of the lymph node stations described by Mountain and Dresler. RESULTS: The CT boundaries of lymph node stations 1-2, 3, 4, 5, 6, 7, 8, 10-11 were defined on axial CT, along with image illustrations. CONCLUSION: These CT-based illustrative definitions will provide guidelines for clinical practice and studies evaluating incidental radiation in radiotherapy. Studies are ongoing at the University of Michigan to measure quantitatively the incidental nodal radiation received by patients with non-small-cell lung cancer.

Humans↗

PubMed2005

Interobserver and intraobserver variability in the assessment of pulmonary nodule size on CT using film and computer display methods.

RATIONALE AND OBJECTIVES: A critical element in determining biologic behavior of pulmonary nodules is volume and temporal volume change. We evaluate variability in nodule volume among readers and measuring methods. MATERIALS AND METHODS: 55 small (<2 cm) lung nodules were measured in long- and short-axis dimensions independently by 4 radiologists, using 3 methods: 1) hard copy, 2) GE Advantage Windows workstation (GE Healthcare, Milwaukee, WI), 3) Siemens IMACS workstation (Siemens Medical Systems, Iselan, NJ). Nodule margin was recorded as smooth, lobulated, or spiculated. Volume was calculated from diameter measurements. Variability in nodule volume was evaluated within each reader, between readers, and across measurement tools. RESULTS: Mean nodule short-axis diameter was 5.3 mm; mean long-axis diameter 7.2 mm. There was statistically significant variation among readers and measurement method for nodule volume. Volume was significantly larger using hard-copy measurements (51.9%-54.1% variation; P < .0001) than either workstation, and not different between workstations. There was greater intraobserver variability in volume using the hard-copy method, and no difference between workstation methods. Volumes based on measurements from one reader were consistently lower than those from other readers (P = < .001, .003, and .02); volume was consistently larger for another reader (P < .0001, .03, and .12). Reader agreement for nodule margin was good to excellent. CONCLUSION: Considerable interobserver and intraobserver variability in measuring nodules exists using hard-copy and computer tools. Since a small change in diameter indicates a much larger change in volume, this may be significant when using early repeat CT to follow small pulmonary nodules. Computer-aided diagnostic tools that reproducibly measure nodule volume are strongly needed.

Humans↗

PubMed2003

Anatomic variations in the levator ani muscle, endopelvic fascia, and urethra in nulliparas evaluated by magnetic resonance imaging.

OBJECTIVE: The purpose of this study was to develop a system to quantify interindividual variation in the appearance of continence system structures in normal continent nulliparous women. STUDY DESIGN: Magnetic resonance imaging (1.5 T) was performed in 20 healthy continent nulliparous women (mean age, 30.1 +/- 5.1 years) with normal pelvic organ support and urodynamics. Morphometric measurements of the levator ani muscle, endopelvic fascia, and urethra were performed. RESULTS: The ratio of the maximum-to-minimum measured values shows that 2- to 3-fold differences occur in distance, area, or volume measures of continence system morphologic features. The mean urogenital hiatus area was 15.2 +/- 2.9 cm(2) in women without a visible connection of the levator ani muscle to the pubic bone (4/20 women) and 12.3 +/- 2.4 cm(2) in women with an levator ani muscle-pubic bone connection (16/20 women, P =.05). CONCLUSION: Considerable variation that was not attributable to limitations of the measuring technique that was used occurs in the size and configuration of the urethral support structures in nulliparous asymptomatic women.

Adult↗

PubMed2003

Aortic intimal tears: detection with spiral computed tomography.

PURPOSE: To determine the frequency, locations, and sizes of aortic intimal tears detected using spiral computed tomography (CT). METHODS: CT scans (26 single detector and 26 multidetector studies) from 52 patients with an unoperated aortic dissection and a patent false lumen were evaluated on a workstation. The number, location, and size of aortic tears were recorded and compared between the following groups: acute and chronic dissection, type A and type B, and single detector and multidetector studies. RESULTS: In 52 patients, 129 tears were identified (mean 2.48 per patient, median 2, range 1-7). There were no significant differences in the number or size of tears between the acute and chronic, the type A and type B, or the single detector and multidetector groups (p>0.05). The most common locations for tears were the descending aorta (57, 44%) and the juxtarenal region (26, 20%). Within the type B category, there was no significant difference in tear locations between the acute and chronic groups (p>0.05). The majority of tears (88, 68%) were < or =1 cm in each dimension. Tears in the thoracic aorta were significantly larger than abdominal aortic tears (p<0.05). CONCLUSIONS: All patients with an aortic dissection and a patent false lumen demonstrated one or more aortic intimal tears using spiral CT. Although most tears were small (</=1 cm), they were usually easily visualized.

Acute Disease↗