Comparison of spontaneous and experimentally induced canine prostatic hyperplasia.

Spontaneous prostatic hyperplasia in the beagle appears to progress with age from a glandular to a cystic histological appearance. Prostatic hyperplasia can be induced in young beagles with intact testes by treatment for 4 mo with either dihydrotestosterone or 5 alpha-androstane-3 alpha, 17 beta-diol, alone, or with either of these steroids in combination with 17 beta-estradiol. In contrast, the induction of prostatic hyperplasia in young castrated beagles, in which the gland had been allowed to involute for 1 mo, requires the administration of both 17 beta-estradiol and either 5 alpha-androstane-3 alpha, 17 beta-diol or dihydrotestosterone. Testosterone and 17 beta-estradiol, either singly or in combination, did not produce the hyperplastic condition in intact or castrated beagles. The experimentally induced prostatic hyperplasia is identical in pathology to the glandular hyperplasia that occurs naturally in the aging dog with intact testes. However, cystic hyperplasia was not produced by any of the treatments tested in young animals.

Spontaneous benign prostatic hyperplasia in the beagle. Age-associated changes in serum hormone levels, and the morphology and secretory function of the canine prostate.

This paper is a cross-sectional study of spontaneous benign prostatic hyperplasia (BPH) in a single canine species. The effects of aging and hormonal changes on the growth, histology, and glandular secretory function of the canine prostate were studied in 42 male beagles ranging in age from 8 mo to 9 yr. The beagle prostate enlarges for at least 6 yr, whether normal or hyperplastic. In contrast, prostatic secretory function, determined by ejaculate volume and total ejaculate protein, declines markedly after 4 yr of age. These reciprocal growth and functional changes in the prostate are closely associated with a progressive increase in the incidence of BPH, which is already apparent in some dogs by age two. With age there is a modest decrease in serum androgen levels with no apparent change in serum 17 beta-estradiol levels. This suggests that the growth and functional changes that are associated with the development of BPH and are initiated very early in life reflect an altered sensitivity of the prostate to serum androgens or a response to the relative decrease in the serum androgen to estrogen ratio.

Upper extremity bone mass and osteoarthritis of the knees: data from the Baltimore Longitudinal Study of Aging.

To examine the association of upper extremity bone mass with osteoarthritis (OA) of the knee, bilateral standing knee radiographs, taken between 1985 and 1991, in 430 Caucasian male and 266 Caucasian female subjects aged 40 years and above in the Baltimore Longitudinal Study of Aging, were read by one investigator for grade of OA using Kellgren-Lawrence scales. Several measures of upper extremity bone mass, size, and density, including combined cortical thickness (CCT), total width and percentage of cortical area of the second metacarpal, and bone mineral content (BMC), width, and density of the distal third of the left radius measured with single photon absorptiometry, were assessed at the same visit. In univariate analyses, men and women with definite knee OA were significantly older, men had significantly greater radial width, and women had significantly lower bone mass as measured by both CCT and BMC. After adjustment for age and body weight, however, men with knee OA had significantly higher BMC and radial width while neither of these measures of upper extremity bone mass and size was significantly associated with the presence of definite knee OA in women. Neither measure of upper extremity bone density was significantly associated with definite knee OA in either sex. These data suggest that, although men (but not women) with definite knee OA have significantly higher levels of adjusted radial bone mass and size, subjects with knee OA do not have significantly higher levels of adjusted bone mineral density at either upper extremity site.

A nonhuman primate model of age-related bone loss: a longitudinal study in male and premenopausal female rhesus monkeys.

Aging is associated with gradual bone loss in men and premenopausal women, with an accelerated rate of loss after menopause in women. Although many studies have investigated bone loss due to surgically induced estrogen depletion, little is known regarding normal age-related changes in bone mass in animal models. We used dual-energy X-ray absorptiometry (DXA) to measure bone mineral density (BMD), bone mineral content (BMC), and projected area (PA) at four skeletal sites over 4 years in 20 premenopausal female (8-23 years) and 29 male (8-27 years) rhesus monkeys (Macaca mulatta). Forearm BMD declined with age in both male and female monkeys. Lean mass was positively associated with BMD at all sites in males and with the distal radius in females. Serum osteocalcin declined and urinary cross-links increased with age in males but not females. Serum 25-hydroxyvitamin D concentrations decreased with age in females, and a similar trend was observed in males. In conclusion, an age-related decline in forearm BMD was observed in male and female rhesus monkeys. Total body BMC declined over time in older females, with a similar trend in males. Changes in markers of bone turnover with age were also observed in male monkeys. The results of this longitudinal study suggest that the rhesus monkey is a potential model for age-related changes in the human skeleton.

Growth potential of porcine reduced-size mature pulmonary lobar transplants.

The use of mature pulmonary lobes for pediatric lung transplantation has recently been described. Successful application of this technique could help alleviate the pediatric donor lung shortage. Whether an already mature lobe can grow by forming new alveolar units after transplantation into a developing recipient is not known. We therefore measured functional residual capacity, fixed lung volume and weight, alveolar size and air space volume percent, and total number of alveoli in mature left lower lobe porcine lung transplants 12 weeks after transplantation into growing piglets. Comparisons were made with nontransplanted mature left lower lobes to determine if functional or morphologic growth had occurred after transplantation. The transplanted and control lobes were all taken from 6-month-old animals (mean body weight 105 +/- 4 kg). Recipients of the transplanted lobes were 9 weeks old and weighed 22 +/- 2 kg. By the end of the 12-week holding period, the recipient animals increased their body weight approximately fourfold (85 +/- 4 kg). No significant differences were seen in functional residual capacity or morphologic analysis of total alveolar number and alveolar size between the transplanted and nontransplanted lobes (p = not significant). Although the reduced-size mature porcine lobar transplants did not display a significant increase in either functional residual capacity or total alveolar number, there was significant growth of the transplanted mature lobes as determined by fixed volume and total lobar weight (p < or = 0.05 versus control animals).

Effect of image display on the quality of multiplanar reconstruction of computed tomography data.

RATIONALE AND OBJECTIVES: The objective of this study is to determine whether the use of edge-enhancement post-processing filters was useful in the computed tomographic (CT) multiplanar evaluation of skeletal trauma. METHODS: The group consisted of a series of 10 cases of skeletal trauma (3 cases of acetabular fractures, 3 cases of tibial plateau fractures, and 4 cases of ankle fractures). All patients had a CT scan using a scan protocol of 4-mm collimation and 3-mm interscan interval. All transaxial images were reconstructed with both a standard algorithm and with an edge-enhancement filter. The images from each group were then reconstructed into coronal and sagittal planes. Three individuals independently reviewed each case and compared image pairs to determine whether images using an edge-enhancement filter were of better or worse quality than standard images. RESULTS: The reviewers found the images with edge-enhancement to be equal to or superior to images reconstructed with a standard algorithm, regardless of the image plane chosen. This bias was especially true in cases of hip and ankle trauma. CONCLUSIONS: When CT supplemented by multiplanar imaging is used in patients with skeletal trauma, image data reconstruction should be done with an edge-enhancement filter to optimize image detail.

The value of immediate cytologic evaluation for needle aspiration lung biopsy.

RATIONALE AND OBJECTIVES: The authors evaluate the role of immediate cytologic evaluation (ICE) with fine-needle aspiration biopsy (FNAB) for lung lesions at highest risk for pneumothorax. METHODS: A prospective randomized study was conducted of 80 patients with lung lesions surrounded by aerated parenchyma undergoing FNAB with and without ICE (47 and 33 patients, respectively). An analysis of needle passes, procedure time, complications, specimen adequacy, diagnostic yield, and accuracy of procedure was made. RESULTS: There was an increased number of needle passes with ICE (> or = three passes: 23% [11 biopsies] versus 3% [1 biopsy]; P = 0.01). Fluoroscopic procedures took longer with ICE (median time: 15 versus 9 minutes; P = 0.002) with no difference in complication rates. Specimen adequacy was similar (74% and 64%) and the procedure was diagnostic in 79% (37 biopsies) with ICE and in 70% (33 biopsies) without ICE. There were no significant differences in the sensitivity, specificity, or accuracy of the biopsy. CONCLUSIONS: Immediate cytologic evaluation improved results marginally with increased procedure time and needle passes. Immediate cytologic evaluation may be most useful for lesions at lowest risk of complications to assure that a second procedure is not required.

Predicting femoral neck strength from bone mineral data. A structural approach.

An interactive computer program was developed to derive femoral neck geometry from raw bone mineral image data for an estimate of hip strength using single plane engineering stress analysis. The program, which we call Hip Strength Analysis (HSA), was developed as an attempt to improve the predictive value of hip bone mineral data for osteoporosis fracture risk assessment. We report a series of experiments with an aluminum phantom and with cadaver femora, designed to test the accuracy of derived geometric measurements and strength estimates. Using data acquired with both Lunar DP3 (DPA) and Hologic QDR-1000 (x-ray) scanners, HSA computed femoral neck cross-sectional areas (CSA) and cross-sectional moments of inertia (CSMI) on an aluminum phantom were in excellent agreement with actual values (r greater than .99). Using Lunar DP3 data, CSA and CSMI measurements at mid-femoral necks of 22 cadaver specimens were in good general agreement with literature values. HSA computed cross-sectional properties of three of these specimens were compared with measurements derived from sequential CT cross-sectional images. Discrepancy between the two methods averaged less than 10% along the length of the femoral neck. Finally, breaking strengths of 20 of the femora were measured with a materials testing system, showing better agreement with HSA predicted strength (r = .89, percent standard of the estimate (%SEE) = 21%) than femoral neck bone mineral density (r = .79, %SEE = 28%).

Reliability of grading scales for individual radiographic features of osteoarthritis of the knee. The Baltimore longitudinal study of aging atlas of knee osteoarthritis.

RATIONALE AND OBJECTIVES: The authors present an atlas of individual radiographic features of osteoarthritis of the knee and evaluate the inter- and intra-reader reliability of trained readers using this atlas. METHODS: Four trained readers graded 30 standing anterior-posterior knee radiographs for eight selected features of osteoarthritis (medial and lateral osteophytes, joint space narrowing, and sclerosis; osteophytes of the tibial spines and chondrocalcinosis) as well as the Kellgren-Lawrence global scale. Inter- and intra-reader reliability were calculated using intraclass correlation coefficients. RESULTS: For all features except sclerosis and osteophytes of the tibial spines, inter-reader reliability ranged from 0.63 to 0.83, whereas intra-reader reliability ranged from 0.82 to 0.95. CONCLUSION: Using this atlas, trained readers are reliable in measuring the presence and severity of individual radiographic features of osteoarthritis of the knee. This atlas should be useful in clinical and epidemiologic studies of osteoarthritis of the knee.

Denervation of the immature porcine lung impairs normal airway development.

Reimplantation or allotransplantation of the immature porcine left lower lobe results in long-term functional dynamic airway obstruction that is associated with abnormally small distal airways. We have attributed this small airway size to bronchoconstriction resulting from chronic denervation rather than to impaired airway growth. To further investigate these findings, we transplanted mature left lower lobes from adult pigs into young piglets after left pneumonectomy. After approximately 12 weeks of somatic growth, the lobes were harvested and fixed through the airways with formalin. Cross-sectional areas of terminal, noncartilaginous airways from the lung periphery were traced on a video monitor. Five groups were examined: control innervated mature left lower lobes, innervated left lower lobes subjected to compensatory growth after left upper lobectomy at approximately 9 weeks of age, mature left lower lobe transplants, reimplanted immature left lower lobe autografts, and transplanted immature left lower lobe allografts. Unlike the immature porcine lobe, transplantation of the mature porcine lobe does not result in abnormally small airways. The small airways seen after transplantation or reimplantation of the immature porcine lobe are likely, therefore, to be due to impaired airway development and not to bronchoconstriction caused by denervation.

B-scan ultrasound in the diagnosis of popliteal aneurysms.

Sonography gives a characteristic picture of popliteal aneurysms, with an easily demonstrable connection of the sonolucent aneurysmal sac with the popliteal artery. It is a good screening procedure for suspected aneurysms and for patients with popliteal pain, mass, or sudden distal ischemia. Three case reports of five popliteal aneurysms diagnosed by ultrasound are presented. A case of neurofibrosarcoma occurring in the popliteal fossa is shown for comparison.

One hundred consecutive thymectomies for myasthenia gravis.

BACKGROUND: Between June 1997 and November 1993, 100 consecutive thymectomies for myasthenia gravis were performed at University of North Carolina Hospitals in Chapel Hill. METHODS: A consistent, planned protocol involving preoperative, intraoperative, and postoperative care was followed. All thymectomies were performed through a median sternotomy with removal of all visible thymus and perithymic fat in the anterior mediastinum. RESULTS: There was no perioperative mortality or longterm morbidity. Mean postoperative hospital stay was 6.3 days (range, 3 to 18 days). Ninety-six percent of the patients were extubated the day of the operation, and all patients were extubated within 24 hours. Mean postoperative intensive care unit stay was 1.2 days (range, 1 to 4 days). After a mean follow-up of 65 months (range, 1 to 199 months), 78% of all patients are improved by at least one modified Osserman classification when their current status is compared with their worst preoperative disease severity. In fact, 69% of patients with mild disease preoperatively (class I, II, or III maximal severity) are in pharmacologic remission (asymptomatic without regular medication), whereas 29% of patients with severe disease (class IV or V) are in remission (p = 0.0001). CONCLUSIONS: Our programmatic approach to thymectomy through a sternotomy has shown minimal morbidity and mortality. It is beneficial to myasthenics at both ends of the age and severity spectrum.

Clinical significance of serum acid phosphatase levels in advanced prostatic carcinoma.

This cooperative study was sponsored by the National Prostatic Cancer Project to determine the usefulness of serum acid phosphatase levels as a predictive indicator with regard to performance status, sites of metastases, response to treatment, and survival in patients with advanced prostatic carcinoma. The results indicate that survival was significantly shorter for those patients who had elevation of thier on-study (pretreatment) total serum acid phosphatase ler cent reduction of primary tumor mass, relief of pain, and acid phosphatase activity. No correlation could be demonstrated between serum acid phosphatase and performance status, site of metastases, and other criteria of response to therapy. It is concluded that this test as currently determined spectrophotometrically at this stage of disease and if employed alone is not sufficient to allow for total evaluation of the response of therapy. It is, however, helpful when used in correlation with the previously mentioned positive factors.

Prostatic carcinoma. relationship between primary tumor, histologic grade, and response to chemotherapy.

This National Cooperative Study has randomly compared the usefulness of 5-fluorouracil (5-FU), cyclophosphamide (Cytoxan) and standard therapy in patients with advanced carcinoma of the prostate (Stage D). All patients studied were endocrine failures and were in progression. Favorable responses were seen with all three treatments regardless of histologic grade. Actual tumor regression occurred only in patients who received either 5-FU or cyclophosphamide. In patients with poorly differentiated or anaplastic tumors treated with cyclophosphamide, progression of disease was significantly less rapid than in patients treated with 5-FU or standard therapy. However, favorable responders could not always be identified in advance on the basis of histologic grade alone.

Chemotherapy of advanced prostatic cancer. Evaluation of response parameters.

A total of 125 patients with progressing advanced prostatic cancer were entered into a chemotherapy study comparing cyclophosphamide, 5-fluorouracil, and standard therapy. Parameters of response were studied in 110 patients who could be evaluated. Thirty-six patients (33 per cent) were considered to have an objective response, that is becoming stable (29 patients) or in partial regression (7 patients). Negative response parameters (predictors of a poor response to chemotherapy or standard theraphy leading to progress) included (1) bone marrow evidence of prostatic cancer, (2) abnormal liver scan, (3) prior radiation therapy (indirectly through increased toxicity to chemotherapy), and (4) lack of bilateral orchiectomy prior to randomization. Positive indicators (predictors of good responses) included (1) reduction of primary tumor mass, especially after administration of 5-fluorouracil or cyclophosphamide, and (2) hemoglobin values. There were more objective responders to cyclophosphamide than standard therapy whether the hemoglobin was initially normal or low. Indeterminate parameters of response included weight gain, presence of bony or soft tissue metastases, relief of pain, performance status, excretory urography, and biochemical determinations of liver and renal function.

Association of radiographic features of osteoarthritis of the knee with knee pain: data from the Baltimore Longitudinal Study of Aging.

OBJECTIVE: To examine the association between self-reported knee pain and radiographic features of osteoarthritis (OA) of the knee. METHODS: A sample of participants in the Baltimore Longitudinal Study of Aging (452 Caucasian males and 223 Caucasian females) completed questionnaires and underwent a standing radiograph of both knees at the same biennial visit between 1984 and 1989. Radiographs were interpreted using both the Kellgren-Lawrence and individual features scales. Odds ratios were calculated for the association of radiographic features with knee pain after adjustment for age, sex, and body mass index. RESULTS: Overall, 156 (23%) persons reported ever having knee pain, and 104 (15%) reported current knee pain (within the previous year). Both ever knee pain and current knee pain were significantly associated with the presence of definite knee OA (Kellgren-Lawrence grade > or = 2) and with the presence of all individual features. There was a direct relationship between all measures of severity of radiographic OA and knee pain. CONCLUSION: These data demonstrate that radiographic features of knee OA are significantly associated with knee pain. The data also support the continued use of the Kellgren-Lawrence grading scale for defining knee OA in population studies.

Experimental testing of a DEXA-derived curved beam model of the proximal femur.

This study was designed to test whether, using curved beam theory, a structural model of the proximal femur derived from two-dimensional dual energy x-ray absorptiometry could be used to predict femoral strength in an experimental simulation of a fall on the greater trochanter. A set of 22 fresh cadaveric femoral specimens were scanned with use of two-dimensional dual energy x-ray absorptiometry and then were tested to failure in a materials testing system, under three-point loading, with the ground impact vector aligned within the plane and along the bisector of the femoral neck-shaft angle. Failure locations generally corresponded to stress peak locations predicted by the curved beam model. Predicted failure loads correlated well with measured failure loads for femoral neck fractures (r=0.89; percent SE of estimate=23%) and some-what less well for intertrochanteric fractures (r=0.83; percent SE of estimate=29%). Overall predictions for failure load calculated from the maximum stress peak value over both locations corresponded to measured failure loads with an r value of 0.91 (percent SE of estimate=21%). This kind of structural approach to the analysis of data for hip bone mass has the potential to provide mechanistic interpretations of the statistical associations frequently shown between conventional bone mineral measures and either hip fracture risk in vivo or bone strength in vitro.

Case report: Phrenic artery injury--a rare complication of percutaneous needle lung biopsy.

The phrenic artery is a small vessel that is not often visualized on CT and is at risk of injury during biopsy of low lung lesions. This may result in haemoperitoneum that will not be evident on post-biopsy chest X-rays. We present a patient with a bleeding tendency who had this unusual complication following a needle aspiration lung biopsy.

Three-dimensional imaging of acetabular trauma.

Computed tomography (CT) scanning is widely used in evaluation of acetabular fractures. Three-dimensional (3D) images of the pelvis can be created from CT scan data. This article reports two studies, each employing one type of 3D imaging in acetabular trauma cases. The first was a study of 21 patients utilizing surface-rendered 3D images, the second, a study of 19 patients using volume-rendered 3D images. Both types of 3D images were clinically helpful and can be used in lieu of conventional plain films as a supplement to CT examination. Advantages of volume-rendered images are described.

Detection of internal mammary lymph node enlargement: comparison of CT scans and conventional roentgenograms.

Sixty-two patients with breast cancer had thoracic computed tomography (CT) scans and conventional chest radiographic (CXR) examinations separated by an average of 29 days. CT served as the gold standard showing 13 cases with enlarged internal mammary nodes 0.4 to 7 cm in diameter. Original CXR interpretations were available. Additionally, these films were reinterpreted, without knowledge of the CT results, with special attention to the retrosternal region on the lateral film including the use of a bright light and comparison to prior lateral views. Original CXR interpretations detected only one (7 cm) enlarged node. Sensitivity was 8% and specificity 100%. Reinterpretation of the CXRs, without knowledge of the CT results, with special attention to the retrosternal region yielded five true positive and seven false positive determinations for a sensitivity of 38% and specificity of 86%. No enlarged node under 2.5 cm in diameter was detected on CXR. Sensitivity of CXR can be considerably improved by careful evaluation of the retrosternal space, but at the cost of considerable increase in false positive examinations. CT is necessary to achieve reasonable sensitivity and specificity in the detection of internal mammary lymphadenopathy.