Image quality and radiation levels in videofluoroscopy for swallowing studies: a review.

Inexpensive video recording equipment coupled to conventional x-ray fluoroscopes is now in widespread use by clinicians for the evaluation of patients with swallowing disorders. The prevalence and simplicity of this apparatus have encouraged its use by clinical specialists who are often not specifically trained in the safe use of x-ray equipment, and this may not be in the best interest of either the patient or the examiner. This has prompted an overview of the operating principles of videofluorescopy equipment. The factors governing image quality are discussed as well as potential hazards and protective measures for both patients and operator. A method of estimating the radiation dose to sensitive tissues from a typical swallowing study is included.

Hormonal replacement therapy: mammographic manifestations.

Anecdotal observation of mammographic changes in patients receiving hormonal replacement therapy prompted a retrospective review of a screening population of 1,500 consecutive patients. Thirty patients were identified who underwent mammography both before or after therapy and during therapy. The duration of hormonal replacement therapy ranged from 1 to 72 months (mean, 22.2 months). An increase in fibroglandular tissue was seen on the mammograms of five of the 30 patients (17%) receiving therapy. The mammograms from the remaining 25 patients (83%) showed no change. A proportion of women receiving hormonal replacement therapy will show increased tissue density at mammography. Awareness of this response should temper concern and, in the absence of suggestive anatomic changes, allow for serial, vigilant monitoring of these patients.

Equivocal mammographic findings: evaluation with spot compression.

Seventy-five spot compression views of equivocally suspicious lesions detected at routine mammographic examination of 72 women were reviewed in this retrospective study. Sixty-five of the 75 lesions appeared less suspicious on spot compression views, two did not change, and eight appeared more suspicious. Biopsy findings confirmed that the eight more suspicious lesions were cancer. The adjunctive use of spot compression helped characterize equivocal findings seen on routine mammographic views and improved the accuracy of mammographic interpretation.

Enlargement of the pancreatic head in patients with pancreas divisum.

Pancreas divisum (PD) is a congenital anomaly present in 6-10% of the population. Computed tomography (CT) examinations in eight of 15 patients (53%) with endoscopic retrograde pancreatography (ERCP)-proven PD were interpreted as showing enlargement of the pancreatic head. Two of these had carcinoma, three had pancreatitis limited to the ventral pancreas, and three were normal. Criteria to distinguish nonpathologic enlargement of the pancreatic head due to PD alone from pathologic causes may include homogeneous parenchyma and an absence of other abnormal signs on CT. Because PD may simulate a pancreatic head mass, the radiologist should be familiar with this variant, and ERCP should precede biopsy unless other evidence of malignancy is present.

Paranasal sinuses: CT imaging requirements for endoscopic surgery.

Recent advances in the understanding of mucociliary activity and the pathophysiology of the nasal cavity and paranasal sinuses have revolutionized the surgical management of chronic and/or recurrent sinusitis. Meticulous radiographic delineation of the small structures in this region, coupled with endoscopic evaluation, provides detailed preoperative information regarding morphology and pathology. This information has led to more focused endoscopic surgical procedures, which have dramatically reduced patient morbidity. As a consequence, there is now worldwide interest among otolaryngologists in the radiologic definition of paranasal regional anatomy. For effective interactions between radiologist and otolaryngologist, the former must be prepared to render interpretations that address these "microanatomic" locales. This communication is directed at familiarizing the radiologist with these observations and concepts, considering both normal and disturbed anatomy with their attendant pathophysiologic and therapeutic implications.

Dermal breast calcifications: localization with template-guided placement of skin marker.

Reliable localization of skin calcifications in the breast was achieved with a true tangential view obtained after superimposition of a radiopaque skin marker. The marker was placed with the aid of a localization template. This method expedited such localizations and obviated the need for repeat radiographs to achieve accurate positioning of the marker.

CT demonstration of postanginal sepsis.

A case of postanginal sepsis is presented with a brief discussion of the pathogenesis and presentation of the syndrome. CT scanning can effectively delineate the parapharyngeal inflammatory process, extension along fascial planes, internal jugular vein encroachment and thrombus, as well as septic emboli complications.

External jugular vein thrombosis: CT demonstration.

A case of external jugular venous thrombosis secondary to misplacement of central venous catheter is presented. The CT findings included enlargement of the external jugular vein, central thrombosis, and vessel wall enhancement. Computed tomography is an excellent noninvasive modality for the evaluation of suspected venous thrombosis.

Computed tomography of the neck.

The capabilities of CT to distinguish between soft tissue structures of varying densities, bone and air, coupled with the added advantage of utilizing intravascular contrast, particularly suits this method of examination to the study of head and neck disorders. With improved equipment permitting thinner sections and shorter exposure times, applications in head and neck diagnosis are increased. CT is used in the evaluation of salivary gland enlargements, staging of known tumors, the evaluation of a variety of neck swellings and in the assessment of laryngeal and facial trauma. In some cases, CT alone may be the only imaging procedure necessary, while in other situations, CT may comprise an important portion of comprehensive imaging evaluation.

Jugular venous thrombosis: diagnosis by computed tomography.

Thrombosis of the internal jugular vein (TIJV) was diagnosed by CT in five patients. Clinical presentations included unexplained fever (four patients), swollen neck (three patients), and mediastinal widening (one patient). Factors contributing to TIJV included placement of a central venous catheter (three patients) and neck surgery (two patients). In two patients left TIJV occurred after right sided venous catheterization. The CT findings consisted of enlargement of the thrombosed vein, a nonenhancing filling defect in the lumen of the affected vessel, an enhancing vessel wall, and opacification of collateral venous channels.

Sclerosing cholangitis. Anatomical distribution of obstructive lesions.

The cholangiograms of 36 patients with sclerosing cholangitis were reviewed. The mean age of the patient group was 43 years, and the mean disease duration was 4.5 years. Seventeen of the patients had associated inflammatory bowel disease. The mean serum bilirubin was 6.8 mg/dl, the mean SGOT was 105 IU/L, the mean SGPT was 108 IU/L, and the mean serum alkaline phosphatase was 534 IU/L. The cholangiograms demonstrated involvement of the extrahepatic bile ducts in 33 patients, involvement of the hepatic duct bifurcation in 33 patients, and involvement of the intrahepatic bile ducts in 35 patients. The cholangiograms were graded as to the areas of the most severe obstructive involvement. In 24 patients the area of most severe involvement was the hepatic duct bifurcation. In eight additional patients the hepatic duct bifurcation, along with the extrahepatic ducts and/or the intrahepatic ducts, were felt to be the areas most severely affected. This predilection for severe obstructive disease at the hepatic duct bifurcation in sclerosing cholangitis held for both patients with and without inflammatory bowel disease. Thus, most patients with sclerosing cholangitis have cholangiographic evidence of diffuse extrahepatic and intrahepatic biliary tract disease, with the hepatic duct bifurcation being the area generally most severely affected.

Computed tomography in the evaluation of cervical thorotrast granuloma.

Two cases of cervical thorotrast granulomas (thorotrastomas) were evaluated with computed tomography. Computed tomography provided delineation of the precise extent of disease and the relationships of the larynx and carotid vessels to the thorotrastoma. This was helpful in planning surgical management. Computed tomography is of use in determining the extent of thorotrastomas and in planning their treatment.

Teleradiology: results of a field trial.

A microcomputer-based teleradiology system was tested over a six-month period by linking a medical center with four distant clinics. Data from more than 4,000 diagnostic x-ray examinations were digitized and transmitted from the clinics to the center, where they were displayed on video terminals and interpreted by 30 military and civilian radiologists. The original radiographs were interpreted independently and the video and film reports compared to determine the feasibility of the teleradiology system. Evaluation of the clinical effectiveness of the system indicated that the quality of the video images resulted in diagnostic findings and impressions that were somewhat less accurate than those reported from comparable film images.

Sclerosing cholangitis: biliary reconstruction with Silastic transhepatic stents.

Because of multiple areas of stricturing and small fibrotic ducts, sclerosing cholangitis has generally not been amenable to direct reconstructive procedures. In reviewing the cholangiograms of 29 patients with sclerosing cholangitis, it became apparent that despite diffuse disease, the hepatic duct bifurcation was often (22 patients) the most severely narrowed area. Because of this finding it was decided to manage patients who have sclerosing cholangitis, persistent jaundice, and hepatic duct bifurcation narrowing with a direct surgical approach. In 11 patients the extrahepatic biliary tree including the bifurcation was resected and the right and left hepatic ducts were dilated. Bilateral 6 mm silicone rubber (Silastic) transhepatic biliary stents were inserted and bilateral hepaticojejunostomy was performed. Eight patients were men, three were women, and the mean age was 41.9 years. At the time of surgery the mean serum bilirubin concentration was 15.3 mg/dl (range 1 to 50 mg/dl). The disease had been present clinically for a mean duration of 3.6 years. There was one hospital death. Nine of the ten remaining patients have responded with a decrease in serum bilirubin concentration to a mean of 2.9 mg/dl. These nine patients have returned to normal activity. The tenth patient has done poorly and awaits liver transplantation. Follow-up ranges from 4 to 36 months (mean 18 months). The stents have been left in position permanently.

Computed tomography of the neck.

Thorough familiarity with the anatomy of the neck depicted in axial sections is fundamental to the interpretation of computed tomography (CT) scans. Fifteen consecutive sections are selected at 1 cm-intervals beginning at the level of the nasopharynx and extending down to the level of the thoracic inlet. Each scan is referenced to a profile drawing of the neck. Each CT scan is reproduced in the line drawing, which is labeled for major organs and discrete structures appearing in that section. Twelve representative cases illustrate the usefulness of CT in the evaluation of neck masses by documenting tumor size, location and relationship to adjacent structures. Intravenous contrast improves recognition of vascular structures and distinguishes lymph nodes from blood vessels. The location and relative density of lesions facilitate their specific identification. Demineralization of bone and cartilage is accurately documented in the illustrative cases. Symmetry is the key to the interpretation of subtle pathologies.

Teleradiology: an evaluation of a microcomputer-based system.

A laboratory evaluation of a microcomputer-based teleradiology system is described. The system used state-of-the-art hardware, and provided for contrast and brightness control by the consulting radiologists. The transmitted, digitized images were compared with conventional radiographs. The radiologists' scores for findings, impressions, and confidence levels were significantly lower for radiographic images viewed on the teleradiology system. However, the quality of the images provided by the teleradiology system was high enough to warrant further study, especially since microcomputer-based teleradiology offers the advantage of providing access to radiology services for rural areas and small hospitals.