Mass-like peripheral zone enhancement on CT is predictive of higher-grade (Gleason 4 + 3 and higher) prostate cancer.

PURPOSE: To determine whether focal peripheral zone enhancement on routine venous-phase CT is predictive of higher-grade (Gleason 4 + 3 and higher) prostate cancer. MATERIALS AND METHODS: IRB approval was obtained and informed consent waived for this HIPAA-compliant retrospective study. Forty-three patients with higher-grade prostate cancer (≥Gleason 4 + 3) and 96 with histology-confirmed lower-grade (≤Gleason 3 + 4 [n = 47]) or absent (n = 49) prostate cancer imaged with venous-phase CT comprised the study population. CT images were reviewed by ten blinded radiologists (5 attendings, 5 residents) who scored peripheral zone enhancement on a scale of 1 (benign) to 5 (malignant). Mass-like peripheral zone enhancement was considered malignant. Likelihood ratios (LR) and specificities were calculated. Multivariate conditional logistic regression analyses were conducted. RESULTS: Scores of "5" were strongly predictive of higher-grade prostate cancer (pooled LR+ 9.6 [95% CI 5.8-15.8]) with rare false positives (pooled specificity: 0.98 [942/960, 95% CI 0.98-0.99]; all 10 readers had specificity ≥95%). Attending scores of "5" were more predictive than resident scores of "5" (LR+: 14.7 [95% CI 5.8-37.2] vs. 7.6 [95% CI 4.2-13.7]) with similar specificity (0.99 [475/480, 95% CI 0.98-1.00] vs. 0.97 [467/480, 95% CI 0.96-0.99]). Significant predictors of an assigned score of "5" included presence of a peripheral zone mass (p < 0.0001), larger size (p < 0.0001), and less reader experience (p = 0.0008). Significant predictors of higher-grade prostate cancer included presence of a peripheral zone mass (p = 0.0002) and larger size (p < 0.0001). CONCLUSION: Focal mass-like peripheral zone enhancement on routine venous-phase CT is specific and predictive of higher-grade (Gleason 4 + 3 and higher) prostate cancer.

Left ventricular ejection fraction in severe chronic obstructive airways disease.

The subject of left ventricular involvement in chronic obstructive airways disease is controversial. We measured left ventricular ejection fraction (LVEF) in 120 patients with severe chronic obstructive airways disease, 92 of them acutely decompensated and 28 stable. A bedside radionuclide technic using a scintillation probe was used to measure LVEF. Of the 28 patients with acute respiratory failure, LVEF was normal (larger than or equal to 55 per cent) in 60 and subnormal in 32. Of the 28 patients with stable chronic obstructive airways disease, LVEF was normal in 12 and low in 16. Coronary artery disease could be demonstrated clinically or at autopsy in 13 of the patients with acute and in 7 of the patients with stable chronic obstructive airways disease. LVEF was 28 plus or minus 10.4 per cent (average plus or minus SEM) in the patients with acute chronic obstructive airways disease and coronary artery disease which was significantly different (P smaller than 0.001) from LVEF in patients without coronary artery disease (61 plus or minus 1.9 per cent). In the patients stable with chronic obstructive airways disease and coronary artery disease, LVEF was (42 plus or minus 3.5 per cent), significantly different (P smaller than 0.001) from LVEF in those without coronary artery disease (55 plus or minus 2.1 per cent). There was no relationship between LVEF and arterial oxygen, or carbon dioxide tension, or pH. Results suggest that LVEF is normal in patients with severe lung disease alone and that reduced LVEF in patients with chronic obstructive airways disease can reasonably be ascribed to coronary artery disease.

Magnetic resonance imaging during intracavitary gynecologic brachytherapy.

The cases of three patients, two with Stage III-B and one with Stage II-B carcinoma of the cervix, are cited to illustrate specific advantages of magnetic resonance (MR) imaging over computed tomography (CT) during intracavitary gynecologic brachytherapy. CT and MR were performed during the first of two intracavitary implants. To obtain artifact-free images with the intracavitary implant in place, a CT- and MR-compatible Fletcher system applicator was used. Although CT failed to differentiate the cervical tumor clearly from surrounding tissues, the area of pathology could be identified on MR by comparing the T1-weighted (T1W) and T2-weighted (T2W) images. Cervical tumors typically exhibit low-signal intensity on T1W and high-signal intensity on T2W scans, whereas paracervical soft tissues demonstrate high intensity on both T1W and T2W images. This contrast permits the size, location, and paracervical involvement of the tumor to be defined by MR. Multiplanar MR images obtained during the patients' intracavitary brachytherapy help demonstrate the actual anatomic relationship between the tumor and the applicator. Isodose distributions displayed on these images show that, in two cases, the tumor margin extended beyond the prescribed isodose line. Thus, MR may prove to be a clinically useful reference during intracavitary brachytherapy for ascertaining radiation dose to actual tumor volume.

Transbronchial lung biopsy via the fiberoptic bronchoscope. Experience with 107 consecutive cases and comparison with bronchial brushing.

Transbronchial lung biopsy (TBB) was performed during fiberoptic bronchoscopy under fluoroscopic guidance in 107 patients. TBB was diagnostic in 17 of 21 (81 percent) cases with localized malignant lesions greater than 4 cm in diameter and bronchial brushing was positive in 12 (57 percent). TBB was diagnostic in 14 of 24 (58 percent) cases with localized malignant lesions equal to or less than 4 cm in diameter, whereas brush biopsy was positive in 7 (29 percent). In 13 cases with suspected Pneumocystis carinii pneumonia, the combination of TBB and brush biopsy was diagnostic of P carinii pneumonia in all 11 patients; TBB was diagnostic in 10 and brush biopsy diagnostic in 5. Cytomegalovirus pneumonitis was diagnosed in the other two cases. In 20 patients with localized infiltrates or nodules, a TBB diagnosis of acute or chronic inflammation excluded malignancy in 15 of 18 cases (follow-up 3 to 24 months) and tuberculosis was diagnosed in 2. Malignancy was found in one patient with acute inflammation on TBB. TBB accurately diagnosed 23 of 29 (79 percent) cases of diffuse lung disease. Following TBB, one patient had pneumothorax and nine patients had hemoptysis not requiring treatment. TBB and bronchial brushing via the flexible fiberoptic bronchoscope offer good diagnostic accuracy and a low complication rate in both diffuse and localized lung diseases.

Quantitative radiocardiography in major pulmonary thromboembolism.

Cardiac index (CI) and pulmonary blood volume index (PVBI) were measured by quantitative radiocardiographic studies using radioactive 113mindium and a scintillation probe in 37 patients with confirmed major pulmonary thromboembolism. The mean PBVI was 185 +/- 11 ml/sq m (SE) and was significantly less than normal (310 +/- 5 ml/sq m [SE]; P less than 0.001). Six patients with major pulmonary thromboembilism had a PBVI within the normal range (262 to 358 ml/sq m; mean +/- 2 SD), and the mean pulmonary vascular occlusion was 21 percent in these patients. Eighteen patients (49 percent) died, and the most significant correlate of mortality was CI, which was depressed (less than 2.7 L/min/sq m) in all but two. Twenty-three serial determinations of pulmonary blood volume (PBV) ranging from 1 to 18 days after the initial study showed a mean increase in PBV of 27 ml/day in ten survivors. Quantitative radiocardiographic studies provide a means of diagnosing major pulmonary thromboembolism by measuring decreases in PBVI; it can assess the magnitude of major pulmonary thromboembolism and can assess CI and, thereby, predict risk of mortality; and it provides a means of following the resolution rate of major pulmonary thromboembolism.

A computer program for calculation and interpretation of pulmonary function studies.

A computer program to calculate and interpret the standard pulmonary function tests has been developed on a programmable calculator system. The program computes both predicted and measured values for static and dynamic lung volumes, airways resistance and diffusing capacity. It then checks for differences between predicted and obtained values and interprets them according to a specific, clinically useful set of diagnostic criteria. By acquisition of a reliable and easy-to-use data processing system, a pulmonary function laboratory can significantly increase the efficiency and accuracy of its day-to-day work.

Impact of pre-radiology clinical years on resident performance.

In 1971, the American Board of Radiology dropped the requirement for at least one pre-radiology clinical year (PRCY) of training. However, requiring a clinical year for radiology residents remains a controversial issue. We reviewed 896 rotation evaluation forms involving 62 residents to see if a difference in performance could be detected between residents who entered training without or with at least one PRCY. Forty-five residents had no previous clinical training, whereas 17 had one or more PRCYs. No significant differences were detected in resident performance between non-PRCY and PRCY residents, nor were differences found by sex, age, presence of non-medical postgraduate degrees, or scores on the first part of the National Board of Medical Examiners. No study of PRCY versus non-PRCY residents can be adequately controlled; thus the failure to show a difference in performance must be interpreted with caution.

Traumatic pneumoperitoneum. Implications of computed tomography diagnosis.

Pneumoperitoneum detected on plain radiographs following blunt abdominal trauma is nearly pathognomonic of bowel perforation and usually mandates exploratory laparotomy. To determine the significance of computed tomography (CT)-detected pneumoperitoneum, we reviewed the clinical records and imaging studies of all trauma patients in our hospital over a seven-year period whose abdominal CT scans showed free intraperitoneal gas. Patients who had penetrating injuries or peritoneal lavage prior to CT were excluded. Of the 18 patients who met these inclusion criteria, surgically confirmed bowel injury was found in only four (22%). In the remaining 14 patients, no evidence of gastrointestinal perforation was found by exploratory laparotomy (2 patients), diagnostic peritoneal lavage (4 patients), GI studies and clinical follow-up (6 patients), or clinical follow-up alone (5 patients). Seven patients had a pneumothorax as a possible cause for pneumoperitoneum. Two additional patients were on mechanical ventilation. Unlike pneumoperitoneum seen on plain film, CT-detected pneumoperitoneum is not pathognomonic of bowel perforation. While laparotomy is not mandatory in the non-surgically explored patient, close clinical observation is essential, and additional diagnostic tests such as peritoneal lavage or radiographic contrast studies can be beneficial to confirm the absence of intestinal injury.

Pulmonary artery hypertension in chronic obstructive pulmonary disease: determination by chest radiography.

Pulmonary artery hypertension is a frequent complication of severe chronic obstructive pulmonary disease (COPD). A study was undertaken to determine whether analysis of the chest radiograph can reveal the presence of pulmonary artery hypertension in COPD. Sixty-one men with COPD (forced expiratory volume in 1 second 0.97 +/- 0.35 liters, mean +/- SD) underwent right heart catheterization, and in 46 the mean pulmonary artery pressure was elevated (greater than 20 mmHg). Plain chest radiographs of the 61 patients and 42 normal control subjects were evaluated. The right descending pulmonary artery (RDPA) was enlarged (greater than 16 mm) in 43 of 46 patients (93%) with an elevated mean pulmonary artery pressure, and the left descending pulmonary artery (LDPA) diameter also was enlarged (greater than 18 mm) in 43 of 46. Combined increased RDPA and increased LDPA diameter measurements permitted correct diagnosis in 45 of 46 patients (98%) with pulmonary artery hypertension, including all 26 a mild elevation of mean pulmonary artery pressure (21-30 mmHg). There was a significant correlation between pulmonary artery pressure and both RDPA and LDPA measurements. Analysis of RDPA and LDPA diameters on the plain chest radiograph is a sensitive and accurate method of detecting the presence and severity of pulmonary artery hypertension in COPD.

Risk management issues in radial keratotomy surgery.

In this article, reprinted from Ophthalmic Risk Management Digest, the bases for radial keratotomy-related claims and guidelines for avoiding such claims are discussed. In most lawsuits, it is not the procedure itself that is on trial, but the use of unusual technique, improper execution, or inadequacy of informed consent.

Liability issues associated with PRK and the excimer laser.

Given the elective nature of photorefractive keratectomy (PRK), the high expectations of patients, and misconceptions of the general public about refractive surgery, the use of the excimer laser for PRK opens the door to new liability risks for ophthalmologists and, in the comanagement environment, referring optometrists. The authors discuss informed consent, marketing, comanagement, and off-label use guidelines and protocols to help protect ophthalmologists against claims and better defend those that might arise.

Magnetic resonance imaging of the levator ani with anatomic correlation.

OBJECTIVE: To define in women the anatomy of the levator ani muscle visible on magnetic resonance imaging (MRI) so these muscles can be studied in women with prolapse or incontinence. METHODS: Multiplanar T1- and T2-weighted MRI was obtained of two female pelvic cadaver specimens, ages 25 and 33. One specimen was hemisected, with half sectioned in the axial plane and the other half in the coronal plane. The other specimen was sectioned in the coronal plane. Anatomic cross sections of these specimens were correlated with the cadaver MRI and MRI of living patients. One sagittal and two axial series of anatomic sections not imaged were also used for comparison. RESULTS: Serial sagittal and axial MRI demonstrates the pubovisceralis ("pubococcygeus") muscle as it originates from the pubic bone, passes alongside the urethra, vagina, and rectum, and then dorsal to the anorectum. Its muscle bulk, attachment to the distal half of the vagina, and insertion between the internal and external anal sphincters can be seen on axial views. The origin of the iliococcygeus muscle at the arcus tendineus levator ani is seen in axial and coronal images. Coronal and sagittal images demonstrate the relative thickness and medial position of the pubovisceralis muscle compared with the thin, diaphragm-like lateral iliococcygeus muscle. CONCLUSION: Magnetic resonance imaging of the cadaver pelvis demonstrates the detailed anatomy of the levator ani muscle. This is an important precursor to future research of the structure, bulk, and orientation of the levator ani in living women with prolapse.

Diagnostic usefulness of post-void film in intravenous urogram.

A survey was sent to urologists to assess their subjective evaluation of the post-void film in the intravenous urogram (IVU). Most of the urologists believed that the post-void film should be a routine part of all IVUs, particularly in men over forty years of age, and estimated that the film contributed useful information in 30 percent of cases. One hundred fifty IVUs were reviewed to assess the actual value of the post-void film in 119 different patients. In these patients, the postvoid film was seen to give unique information not available by history or films of the filled bladder in only 3 percent of the cases. Therefore, we conclude the post-void film should not be a routine part of every IVU, and should be obtained on an as-needed basis only.

Small echogenic renal masses: how often is computed tomography used to confirm the sonographic suspicion of angiomyolipoma?

OBJECTIVES: Although renal angiomyolipoma (AML) has a typical ultrasound appearance, many authorities suggest that a computed tomography (CT) scan be obtained to confirm the diagnosis because small echogenic renal cell carcinomas can simulate AML. Our study evaluates the actual follow-up in such patients and factors that may affect whether CT confirmation is recommended or obtained. METHODS: From 1986 through 1992, 36 patients had an ultrasound diagnosis of probable renal AML (well-circumscribed, homogenously echogenic mass). In each case the patient's age, symptoms, ultrasound results and recommendations, and imaging follow-up were recorded. RESULTS: CT confirmation of the sonographic diagnosis was recommended in only 11 of 36 (31%) patients. Only 7 of these 11 patients actually underwent CT, 5 of whom had the diagnosis confirmed by CT detection of intratumoral fat. Ten of 23 patients (43%) over 50 years of age had CT recommended, whereas only 1 of 13 (8%) patients under age 50 years did (P < 0.05). CT confirmation was recommended for 5 of 13 (38%) lesions greater than 10 mm and for 6 of 23 (26%) smaller masses. None of the 9 patients under age 50 years with small masses (less than 10 mm) had CT recommended. CONCLUSIONS: Although many authorities recommend CT to confirm the sonographic diagnosis of renal AML, this algorithm is rarely followed in everyday clinical practice, especially in patients under age 50 years with masses less than 10 mm.

Iodinated contrast material in uroradiology. Choice of agent and management of complications.

Many conditions seen by urologists require imaging examinations with iodinated radiographic contrast material as a key part of the primary evaluation of the patient. A basic understanding of contrast media, risks of administration, choice of agents, and premedication regimens for high-risk patients, is beneficial in helping patients prepare for their examinations. Urologists may be the primary physicians administering contrast material or may be working with radiologists in the care of patients receiving contrast agents. Because contrast reactions may occur unexpectedly, even during examinations in which the agents are not given intravenously, urologists should be able to recognize and treat the various types of adverse reactions.

Treatment of adverse reactions to radiographic contrast media in adults.

Prompt recognition and treatment can be invaluable in blunting an adverse response of a patient to radiographic contrast material and may prevent a reaction from becoming severe or even life-threatening. Radiologists and their staff should review treatment procedures regularly (at least annually) so that each staff in attendance can accomplish his or her role efficiently. Knowledge, training, and preparation are crucial in guaranteeing appropriate and aggressive therapy in the event of an adverse contrast-related event.

Impact of myelography on the radiotherapeutic management of malignant spinal cord compression.

From December 1981 through August 1984, 24 patients with spinal cord compression syndrome due to epidural neoplasms were evaluated for radiotherapy with clinical examination, radiographs of the spine, and myelography. All plain films were reviewed, and mock radiotherapy fields designed using specific criteria for margins. The same patients were reviewed a second time considering the additional information provided by myelography. The initial treatment fields were found to be inadequate in 69% of the patients. Even in patients with discrete bony lesions, the results of myelography affected the treatment 45% of the time. A history of previous spinal irradiation significantly influenced port design in only 1 of the 7 patients who had received previous radiotherapy. Although invasive, myelography is essential in planning the treatment of spinal cord compression.

MRI scanner variability studies using a semi-automated analysis system.

Due to the unique design of the Parallel Rod Test Object (PRoTO) and the associated semi-automated analysis program, it was necessary to test it extensively for precision and accuracy, and preliminarily for utility, before its distribution for wider use in MRI system quality control (QC). The test object and analysis program measured the desired quantities reproducibly and they accurately measured predicted changes from intentionally adjusted imaging system parameters, yielding sensitivity of the various test measures to deviation in the system operating parameters. From a single scan of the most recent revision of the test object, multiple quantitative quality control measures were obtained throughout the scanning volume on two MR imaging systems over periods of six and twelve months, respectively. From these and earlier trials, an initial indication was obtained of which performance measures are worth monitoring for QC. This experience suggests that signal-to-noise ratio (SNR) and distortion (including display scale) should be monitored but not necessarily the resolution. The latter was only found to alter at the same time or later than other parameters such as SNR had changed. Slice thickness was found to vary on some units and this measure was also used in normalizing the SNR by voxel volume. SNR, distortion, and resolution measurements using field-echo sequences were less stable than those using spin-echo sequences. Use of this QC program to test a wide variety of image quality measures allowed timely assessment of the long-term variability of the units tested. Long-term variability may become among the most important measures for comparison of system performance and maintenance.(ABSTRACT TRUNCATED AT 250 WORDS)

Signal-to-noise measures for magnetic resonance imagers.

The signal-to-noise ratio (SNR) in magnetic resonance imaging represents one of the system operating variables that must be determined both for evaluating the performance of different imaging protocols on a particular machine, and for monitoring machine performance as part of a routine quality control (QC) program. Utilizing a phantom and set of automated analysis programs currently under development, this study evaluated several ways of measuring image signal and noise and demonstrated the importance of utilizing measured voxel volumes as opposed to nominal volumes in the calculation of SNR. The NEMA proposed standard for SNR is compared with several other SNR measures and is recommended as the measure to be used in routine SNR reporting. The importance of utilizing other SNR measures in addition to the NEMA proposed standard for routine QC is discussed.

Detection of mammalian cell mutagens in urine from carcinogen-dosed mice.

Urine from drug-treated rodents was tested directly in the L5178Y TK+/-leads to TK-/- gene mutation assay for the induction of trifluorothymidine-resistant (TFTR) mutants. 18-h urine samples collected from male CD-1 mice which had been treated with either 2-aminofluorene, cyclophosphamide, or lucanthone were incubated with beta-glucuronidase, then added directly to cultures of L5178Y TK+/- mouse lymphoma cells for 3 h. All 3 urine sources produced significant, dose-dependent increases in the frequency of TFTR mutants compared to normal urine or saline controls. When these same chemicals were tested directly as mutagens in L5178Y TK+/- cells, lucanthone and, to a lesser extent, cyclophosphamide were positive both with or without metabolic activation; and aminofluorene was only positive with activation. These results indicate that the urinary metabolites of aminofluorene, cyclophosphamide, and either the parental molecule or urinary metabolites of lucanthone can readily be detected as mutagens in a mammalian cell assay.