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E K Fishman

Publications and source records attributed to E K Fishman.

At least 19 recordsLinked to original sources

The current state of the art in three dimensional oncologic imaging: an overview.

PURPOSE: To provide an overview of the methods and clinical applications of three dimensional (3D) medical imaging in the oncologic patient. METHODS AND MATERIALS: We briefly outline the techniques currently used to create 3D medical images with an emphasis on their strengths and shortcomings as they relate to oncologic imaging and radiation therapy planning. We then discuss some of the most important and promising oncologic applications of 3D imaging and suggest likely future directions in this rapidly developing field. RESULTS: Since the first application of 3D techniques to medical data over a decade ago, 3D medical images have evolved from relatively crude representations of musculoskeletal abnormalities to detailed and accurate representations of a variety of soft tissue, vascular, and oncologic pathology. The rapid development of both computer hardware and software coupled with the application of 3D techniques to a variety of imaging modalities have expanded the clinical applications of this technology dramatically. CONCLUSIONS: 3D medical images are clinically practical tools for oncologic evaluation and effective radiation therapy planning.

Humans

Primary vs secondary iliopsoas abscess. Presentation, microbiology, and treatment.

OBJECTIVE: To review the characteristics of patient presentation, microbiology, and treatment of primary iliopsoas abscess. DESIGN: A case series of patients with iliopsoas abscess diagnosed on computed tomographic scans from 1987 to 1994. SETTING: Tertiary care inner-city university hospital. PATIENTS: Eleven patients with secondary iliopsoas abscess, defined as being secondary to gastrointestinal or genitourinary causes or trauma, and seven patients with primary abscess, defined as the absence of the above causes. MAIN OUTCOME MEASURES: Patient characteristics, presenting symptoms and signs, microbiologic characteristics, treatment, and clinical course of patients with primary iliopsoas abscesses compared with those in patients with secondary abscesses. RESULTS: In the primary group, six patients (86%) were intravenous drug users and four (57%) were positive for human immunodeficiency virus. Staphylococcus aureus grew from cultures from five of seven patients with primary abscesses, whereas secondary abscesses had enteric flora. The typical patient presentation included fever, with complaints of pain in the flank, hip, or abdomen. Comparison of abscess drainage options showed shorter hospitalizations for surgical drainage than for percutaneous drainage (15.9 vs 28.5 days; P < or = .01). CONCLUSIONS: A patient who presents with pain in the flank, hip, or abdomen may have a primary iliopsoas abscess. Computed tomography is the standard method of diagnosis. Antibiotic regimens for patients with primary iliopsoas abscess should include coverage for S aureus, and patients with secondary abscesses should have antibiotic regimens tailored for enteric bacteria. Drainage of abscess is essential for appropriate treatment, and surgical drainage is superior to percutaneous drainage in achieving prompt recovery.

AIDS-Related Opportunistic Infections

Spiral CT with multiplanar reconstruction in the diagnosis of sternoclavicular osteomyelitis.

OBJECTIVE: The purpose of this study was to determine whether contrast-enhanced spiral ct scanning supplemented by multiplanar reconstruction is of value in the evaluation of suspected infection of the sternoclavicular joints. MATERIALS AND METHODS: Seven patients with suspected infection of the sternoclavicular joints were evaluated with spiral CT using narrow collimation (4 mm) and close interscan reconstruction (2-4 mm). All patients were scanned immediately following the injection of 120 ml Omnipaque-300 at a rate of 3 ml/s. Spiral CT scans were of 24 or 32 s duration and done as single-breath-hold studies. All images were then filmed at soft tissue and bone settings (window width 2300, window center 270). In selected cases, coronal, sagittal, and/or oblique reconstruction of data was done for review. RESULTS: All studies were successfully completed without any interscan or intrascan motion. In six cases, infections of the sternoclavicular joint was found, including five cases of osteomyelitis of the clavicular head. The scans obtained during the phase of high contrast enhancement allowed definition of the extension into the soft tissue and muscle. Bone windows demonstrated subtle cortical and periosteal abnormalities. CONCLUSION: Imaging of the sternoclavicular joints with standard CT can be difficult due to interscan motion and the inability to get good data sets for reconstruction. Spiral CT with 24- to 32-s acquisition allows high quality images enabling detection of disease and definition of extent of disease, thus helping to guide patient management.

Adult

Hepatic leiomyosarcomas: CT features with pathologic correlation.

The purpose of this study was to determine the computed tomographic (CT) features of hepatic leiomyosarcoma and to correlate them with pathologic findings. CT examinations of 15 patients with pathologically proven leiomyosarcoma of the liver were retrospectively reviewed. Three patients had primary leiomyosarcoma of the liver and 12 patients had 43 distinct hepatic metastases originating from a primary gastrointestinal (n = 8), uterine (n = 2) or retroperitoneal (n = 2) leiomyosarcoma. In the 11 patients who had partial hepatic resection or surgical biopsy of their tumors, a correlation was made between CT imaging and pathologic findings. Primary leiomyosarcomas showed heterogeneous enhancement; two displayed internal and peripheral enhancement, and one showed peripheral enhancement with a pseudocystic pattern (i.e. enhancing thick wall with internal nonenhancing low attenuation area). Leiomyosarcomas metastatic to the liver were homogeneous, showing no or moderate enhancement (10 of 43 metastases, 23%) or heterogeneous and predominantly peripheral enhancement (33 of 43 metastases, 77%). A pseudocystic pattern was seen in 13 of the 43 metastases (30%). Homogeneous tumors were made of smooth fibrous-like tissue without area of necrosis. Heterogeneous tumors contained varying degrees of necrosis and hemorrhage or gelatinous tissue. We found that primary and secondary hepatic leiomyosarcomas of the liver can exhibit different features. A pseudocystic pattern is uncommon. Furthermore, purely cystic tumors were not seen in our series.

Adult

Differentiation of benign and malignant musculoskeletal tumors: potential pitfalls with MR imaging.

Magnetic resonance (MR) imaging is the most sensitive and accurate imaging technique for evaluation of musculoskeletal tumors. With increasing clinical experience, however, an overlap between the classic characteristics of benign and malignant tumors is frequently observed. In a prospective analysis of 87 consecutive cases of musculoskeletal tumors, the malignancy of skeletal lesions was correctly assessed with MR imaging in 55% of the cases. In 39% of the cases, the malignancy of skeletal lesions was overestimated with MR imaging. Correlation with plain radiography is extremely important in such cases and would have resulted in correct assessment of 73% of the skeletal lesions. For soft-tissue lesions, a large variability is found in the benign versus malignant appearances of lesions on MR images, with poor correlation between classic benign characteristics and the benignity of the lesion (17% of cases). The exceptions are hemangiomas and lipomas, which have characteristic appearances on MR images. Knowledge of potentially misleading appearances of musculoskeletal tumors on MR images allows more accurate diagnosis of such tumors.

Adolescent

Spiral CT during arterial portography: technique and applications.

Spiral computed tomography during arterial portography (CTAP) combines rapid scanning with selective imaging during the portal phase of enhancement of the liver, resulting in an effective method for evaluation of liver neoplasms prior to partial hepatic resection. Compared with dynamic incremental CTAP, spiral CTAP results in improved quality of three-dimensional and multiplanar reconstructions, facilitating presurgical planning. Accurate volumetric analysis of the tumor can be performed, and subsegmental tumor localization is facilitated by the high levels of hepatic and portal venous enhancement. Additional advantages of spiral CTAP include small reconstruction intervals for improved lesion detection. However, the specificity of spiral CTAP is low because both benign and malignant tumors appear as hypoattenuating perfusion defects. In addition, both focal and geographic nontumorous perfusion defects may be seen more frequently with spiral CTAP than with dynamic CTAP. Knowledge of common diagnostic pitfalls is necessary for accurate interpretation of spiral CTAP images.

Adult

Three-dimensional spiral CT during arterial portography: comparison of three rendering techniques.

The three most common techniques for three-dimensional reconstruction are surface rendering, maximum-intensity projection (MIP), and volume rendering. Surface-rendering algorithms model objects as collections of geometric primitives that are displayed with surface shading. The MIP algorithm renders an image by selecting the voxel with the maximum intensity signal along a line extended from the viewer's eye through the data volume. Volume-rendering algorithms sum the weighted contributions of all voxels along the line. Each technique has advantages and shortcomings that must be considered during selection of one for a specific clinical problem and during interpretation of the resulting images. With surface rendering, sharp-edged, clear three-dimensional reconstruction can be completed on modest computer systems; however, overlapping structures cannot be visualized and artifacts are a problem. MIP is computationally a fast technique, but it does not allow depiction of overlapping structures, and its images are three-dimensionally ambiguous unless depth cues are provided. Both surface rendering and MIP use less than 10% of the image data. In contrast, volume rendering uses nearly all of the data, allows demonstration of overlapping structures, and engenders few artifacts, but it requires substantially more computer power than the other techniques.

Algorithms

CT of the esophagus: spectrum of disease with emphasis on esophageal carcinoma.

The esophagus is involved by a wide range of pathologic processes that can be detected, defined, and staged with computed tomography (CT). These processes include esophageal carcinoma; benign esophageal tumors; inflammatory and infectious diseases; miscellaneous conditions such as Barrett esophagus, achalasia, and varices; and trauma and perforation. CT is usually performed to clarify findings seen with other imaging modalities or to stage a pathologic condition; however, it may be the primary imaging modality in some cases. Because of the critical location of the esophagus, it can be involved secondarily by other disease processes or as part of a systemic process. By being aware of the appearances of the various entities that affect the esophagus, the radiologist can play an important role in detecting and staging esophageal disease. Although the role of CT in the evaluation of esophageal disease has been controversial, recent developments such as spiral CT have the potential to renew interest in this application.

Adult

Radiation therapy of external iliac lymph nodes with lateral pelvic portals: identification of patients at risk for inadequate regional coverage.

PURPOSE: To determine whether "standard" lateral pelvic radiation therapy portals provide adequate margins for treating the external iliac lymph nodes (EILNs). MATERIALS AND METHODS: With computed tomographic (CT) data and a computerized algorithm, the course of the EILN chain was reconstructed in 48 patients. The marginal distance between a consistently localized portion of the EILNs and the anterior field border that was placed at the front of the pubic symphysis was recorded for each patient. RESULTS: The EILNs were covered adequately in only 50% of both men and women. More adequate EILN margins were observed in (a) women older than 68 years, (b) women with small anteroposterior separations, (c) men older than 70 years, and (d) men and women with a low central obesity index. Less adequate margins were observed in men who were obese or men with large anteroposterior separations. In the study population, no correlation was observed for sex, race, or tumor site. CONCLUSION: The authors recommend portals that are designed specifically for patients rather than standard portals that may inadequately cover the intended targets.

Adult

Pulmonary nodules: effect of increased data sampling on detection with spiral CT and confidence in diagnosis.

PURPOSE: To compare spiral computed tomography (CT) with interscan spacing of 4-5 mm versus 8-10 mm for detection rate and level of confidence in diagnosis of pulmonary nodules. MATERIALS AND METHODS: Four radiologists (two junior and two senior faculty members) retrospectively reviewed 67 spiral CT studies with one to six nodules per study. Every second image was masked, which resulted in 8-mm sections every 8 or 10 mm; then all images reconstructed every 4 or 5 mm were reviewed. Lesions were classified as definite, probable, or possible. RESULTS: Narrow interscan spacing yielded more lesions overall (583 vs 566, P < .025) and more definite lesions and fewer equivocal lesions (482 vs 431 and 101 vs 135, respectively; P < .055). The greatest effects were in the reduction of possible lesions (50 vs 88, P < .001) and in the reduction of false-positive diagnoses made by less experienced radiologists. CONCLUSION: Increased reconstruction frequency of spiral CT volume data sets improves detection of pulmonary nodules and enhances confidence in the diagnosis.

False Positive Reactions

Potentially resectable pancreatic adenocarcinoma: spiral CT assessment with surgical and pathologic correlation.

PURPOSE: To evaluate the accuracy of spiral computed tomography (CT) in assessing the resectability of small pancreatic ductal adenocarcinoma and to correlate the CT findings with histopathologic and surgical findings. MATERIALS AND METHODS: Spiral CT scans obtained in 64 patients who underwent surgery for potentially resectable pancreatic adenocarcinoma were prospectively assessed for tumor resectability. CT findings were correlated with surgically assessed extent of tumor and pathologic findings. RESULTS: Fifty-seven (89%) of 64 carcinomas were detected with spiral CT. Twenty-four carcinomas were resectable at surgery and 40 were not. The average size of resectable tumors was 3.1 cm (range, 1.0-7.5 cm). The overall accuracy of spiral CT for assessing resectability was 70%. Of resected tumors, 14 were hypoattenuating compared with the remaining pancreas and 10 were isoattenuating. Eleven tumors showed neointimal proliferation in arterioles at histologic examination. CONCLUSION: Further progress in preoperative staging of pancreatic ductal adenocarcinoma with spiral CT should be directed toward improving detection of small pancreatic tumors and assessment of early metastatic disease.

Adenocarcinoma

Variations in the intrahepatic portions of the hepatic and portal veins: findings on helical CT scans during arterial portography.

OBJECTIVE: The goals of this study were to describe variations in the intrahepatic portions of the hepatic and portal veins as visualized by helical CT during arterial portography (CTAP) and to examine the surgical implications of these findings. MATERIALS AND METHODS: A retrospective review of 69 helical CTAP scans of 69 patients with small hepatic tumors and no evidence of vascular invasion or distortion was done. Axial helical CTAP scans were reviewed to determine the presence, number, and location of intrahepatic portions of the hepatic and portal veins. RESULTS: Among the 60 patients (87%) in whom the right, middle, and left hepatic veins were visualized, 19 (32%) had supernumerary hepatic veins. Right inferior hepatic veins were found in six (9%) of the 69 patients. Variations in intrahepatic portal anatomy were found in four patients (6%) and involved an immediate trifurcation of the portal vein in three patients (4%) and a left main portal vein originating from the right anterior portal branch in one patient (2%). CONCLUSION: Variations in the intrahepatic portions of the hepatic and portal veins are frequently seen on helical CTAP scans. Recognition of such variations is important in the preoperative evaluation of patients with hepatic tumors because these variations may have implications for tumor resection and for planning the operative approach.

Adult

Splenic involvement in pancreatitis: spectrum of CT findings.

The pancreas is located deep within the retroperitoneum in the anterior pararenal space. The distal portion of the pancreatic tail extends along the course of the splenic artery and vein (Fig. 1) and enters the splenic hilum contained within the splenorenal ligament. Because of these anatomic relationships, the spleen and splenic vessels may be involved by pancreatitis. Although rare (frequency, 1-5%), splenic involvement by pancreatitis includes intrasplenic pseudocyst, abscess, hemorrhage, infarction, splenic rupture, and vascular injury. Because these complications can be life-threatening, the extent and course of the disease are closely monitored with CT to determine whether and when aggressive intervention is necessary to avoid catastrophic clinical outcomes. The purpose of this essay is to illustrate the spectrum of CT findings in cases of pancreatitis with splenic involvement.

Humans

Nontumorous low-attenuation defects in the liver on helical CT during arterial portography: frequency, location, and appearance.

OBJECTIVE: Low-attenuation defects in the liver that are caused by variations in the portal perfusion of the liver rather than by intrahepatic tumor can be detected using helical CT during arterial portography (CTAP). The purpose of this study was to characterize these nontumorous low-attenuation defects detected with helical CTAP in terms of their frequency, location, and appearance. MATERIALS AND METHODS: Helical CTAP examinations of 89 patients referred for preoperative evaluation of metastatic or primary liver tumors performed over a 20-month period were retrospectively reviewed by three radiologists. The frequency, appearance, and location of focal (within a subsegment) and diffuse (affecting more than one subsegment) nontumorous perfusion defects were determined. Findings on helical CTAP images were correlated with surgical findings (53 patients), results of MR examinations (25 patients), and follow-up CT examinations (11 patients). RESULTS: Ninety-seven nontumorous perfusion defects were identified in 68 patients. The most frequent defects were located adjacent to the gallbladder fossa (35), anterior to the porta hepatis (34), in the subcapsular portion of the liver (13), and adjacent to the falciform ligament (12). Nontumorous perfusion defects characteristically appeared wedge-shaped or flat and ranged in size from 8-20 mm. CONCLUSION: Nontumorous perfusion abnormalities have characteristic appearances and locations on helical CTAP examinations and are more common than previously reported with conventional CTAP. Familiarity with the locations and characteristic appearances of these defects is essential to prevent false-positive diagnoses, so that operative candidates are not mistakenly denied surgical therapy.

Adult

Imaging of intrahepatic cholangiocarcinoma: 1. Peripheral cholangiocarcinoma.

Cholangiocarcinoma is the second most common primary hepatic malignant tumor after hepatocellular carcinoma, accounting for 5-30% of all primary hepatic malignant tumors [1]. Intrahepatic cholangiocarcinomas can be classified as peripheral cholangiocarcinoma, which originates from an interlobular biliary duct, or as hilar cholangiocarcinoma, which originates from a main hepatic duct or from the bifurcation of the common hepatic duct. Intrahepatic cholangiocarcinomas account for only about half of cholangiocarcinomas, and this pictorial essay focuses only on the peripheral form of the disease. Clinically, therapeutically, and radiologically, these two types of cholangiocarcinomas differ. Features suggestive of the diagnosis of peripheral cholangiocarcinoma can be shown by sonography, CT, and MR imaging. Cholangiography and angiography have a limited role in evaluating this neoplasm that manifests as a focal mass. This essay reviews the appearances of peripheral cholangiocarcinoma and discusses the various imaging techniques that can be used to evaluate this unusual tumor that is often resectable and potentially curable.

Adult

Imaging of intrahepatic cholangiocarcinoma: 2. Hilar cholangiocarcinoma.

Hilar cholangiocarcinoma (also called Klatskin's tumor) is more common than peripheral cholangiocarcinoma. Sonography, CT, MR imaging, angiography, and cholangiography can suggest the diagnosis, but the major issue of imaging with this tumor is to determine whether the tumor is resectable. The anatomic location of hilar cholangiocarcinoma makes resection difficult, so that surgical exploration of patients with this condition should be undertaken only when preoperative evaluation has shown a potential for curative resection. Preoperative assessment of resectability of hilar cholangiocarcinoma is often extensive, requiring several types of imaging. This pictorial essay reviews the imaging features of hilar cholangiocarcinoma. The role of imaging in the preoperative planning, with specific emphasis on staging extent of disease, including hepatic and vascular involvement, is discussed and illustrated.

Adult