Perilobular pulmonary opacities: high-resolution CT findings and pathologic correlation.

This pictorial essay illustrates the high-resolution CT and histologic findings of various disease processes that involve the perilobular interstitium.

Crazy-paving appearance at thin-section CT: spectrum of disease and pathologic findings.

PURPOSE: To determine the spectrum of disease associated with a fine reticular pattern superimposed on areas of ground-glass opacity (i.e., "crazy-paving" appearance) at thin-section computed tomography (CT) and to determine the underlying pathologic features. MATERIALS AND METHODS: In the in vivo study, the cases of 46 patients (21 male, 25 female; age range, 13-82 years) were retrospectively reviewed, with special attention paid to the size and extent of the reticular network. In the in vitro study, the thin-section CT findings in 20 inflated and fixed lungs were precisely correlated with the gross appearance, contact radiograph findings, stereomicroscopic views, and histologic findings. RESULTS: In the in vivo study, 15 different diseases were identified, including alveolar proteinosis, adult respiratory distress syndrome, acute interstitial pneumonia, diffuse alveolar damage superimposed on usual interstitial pneumonia, and drug-induced pneumonitis. In the in vitro study, the fine networks at pathologic analysis were due to an alveolar filling process (n = 10), an interstitial fibrotic process (n = 7), or a combination of interstitial and intraalveolar processes (n = 3). Twelve (60%) cases did not have thickening of the interlobular septa within the areas of the crazy-paving appearance. CONCLUSION: The crazy-paving appearance is a nonspecific finding seen in a variety of interstitial and airspace lung diseases.

Respiratory change in size of honeycombing: inspiratory and expiratory spiral volumetric CT analysis of 97 cases.

PURPOSE: The purpose of this study was twofold: to evaluate the change in size of honeycomb cysts with respiration using inspiratory-expiratory spiral volumetric CT (I-E SVCT) and to establish the pathologic basis of this change. METHOD: Ninety-seven patients, who had honeycombing associated with end-stage pulmonary fibrosis on end-inspiratory 1 to 2 mm collimation high-resolution CT (HRCT), underwent I-E SVCT (3 mm collimation, pitch 1, breath-hold time 20 s, reconstruction interval 1 mm, FOV 16-20 cm, high frequency algorithm). I-E SVCT scans were assessed on images obtained in the transverse plane and volumetric sagittal, coronal, and oblique reformations. The histologic findings were assessed in four inflated and fixed lungs that showed honeycombing at postmortem HRCT. RESULTS: In 63 patients (65%), a small percentage of the cysts did not change in size at end-expiration, while in the remaining patients, all the cysts decreased in size. Assessment of volumetric multiplanar reformations showed that cysts that decreased in size during exhalation communicated with airways and represented bronchiolectasis rather than true cysts, while the other cysts did not communicate with the airways. Similar findings were found in pathologic specimens. CONCLUSION: The majority of, but not all, honeycomb cysts seen on HRCT represent dilated bronchioles that communicate with the proximal airways and change in size with respiration.

A heterozygous frameshift mutation of the PTEN/MMAC1 gene in a patient with Lhermitte-Duclos disease - only the mutated allele was expressed in the cerebellar tumor.

Lhermitte-Duclos disease is a rare disorder of the cerebellum which exhibits a focally indolent growth of the cerebellar cortex. The disease is sometimes associated with multiple hamartoma syndrome, or Cowden disease, an autosomal, dominantly inherited cancer syndrome. Germline mutations of the PTEN/MMAC1 gene, a gene recently discovered to be a tumor suppressor, have been documented in four families with Cowden disease. A family member in one of these families have had Lhermitte-Duclos disease, indicating that mutations of the gene are responsible for the development of Lhermitte-Duclos disease. However, the occurrence of Lhermitte-Duclos disease is mostly sporadic. It is unknown whether the PTEN/MMAC1 gene is involved in these cases. We performed a genetic analysis on a patient with Lhermitte-Duclos disease, as well as analyses on his family members, and found a germline mutation of the PTEN/MMAC1 gene. An insertion of A at nucleotide 83 in codon 28 was apparent in both the patient and members of his family. This mutation caused a frame shift that generated a premature stop codon in codon 43. The mutation was heterozygous, although only the mutated allele was expressed in the cerebellar tumor of the patient. A monoallelic expression of the mutated PTEN/MMAC1 gene may have been responsible for the development of a cerebellar tumor in the patient.

Fractal analysis for classification of ground-glass opacity on high-resolution CT: an in vitro study.

PURPOSE: Fractal analysis based on the fractional Brownian motion model was applied ground-glass opacity on high-resolution CT (HRCT) to investigate its usefulness in distinguishing ground-glass opacity caused by nonfibrotic disease processes and that caused by fibrotic disease processes, confirming pathology. METHOD: Twenty-one postmortem lungs inflated and fixed by Heitzman's method were evaluated. By correlating HRCT and pathology, the lungs were classified into nonfibrotic disease processes and fibrotic disease processes. Fractal analysis based on the fractional Brownian motion model provides the parameter H, which is a statistical measure related to the psychophysical perception of roughness. For regions of interest positioned over ground-glass opacities on HRCT, conventional statistics (mean value and SD) and the estimated H values were calculated using a workstation. RESULTS: Pathologically, 10 lung specimens were categorized as nonfibrotic disease processes and 11 as fibrotic disease processes. Whereas the conventional statistics had considerable overlap in two disease processes, the overlapping was drastically reduced in the H values. The H values of fibrotic disease processes (mean +/- SD, 0.423 +/- 0.064) were significantly greater than those of nonfibrotic disease processes (0.297 +/- 0.036) (p < 0.001). CONCLUSION: Fractal analysis based on the fractional Brownian motion model may provide a new promising scheme for assessing ground-glass opacity on HRCT caused by either nonfibrotic or fibrotic disease processes.

Malignant mesenchymoma of the spermatic cord with a brief review of the literature.

Sarcomas of the spermatic cord are rare, and malignant mesenchymomas are particularly rare. Only 8 cases of paratesticular mesenchymoma have been described previously. We report here the ninth case of malignant mesenchymoma of the spermatic cord, in which there was a local recurrence. We also briefly review the previously reported cases.

Acute interstitial pneumonia: high-resolution CT findings correlated with pathology.

OBJECTIVE: The purpose of this study was to evaluate the relation between pathologic phases and high-resolution CT (HRCT) findings in patients with acute interstitial pneumonia (AIP). MATERIALS AND METHODS: Our retrospective review found 14 patients with AIP who were included in this study. Three patients were pathologically diagnosed as having AIP by open lung biopsy, and the other 11 patients were confirmed at autopsy. In eight of the 11 autopsy patients, the postmortem lungs were inflated and fixed by Heitzman's method, and a postmortem HRCT scan was obtained on all 11 autopsy patients. Paying special attention to the disease stage, we selected 27 areas of the lung from antemortem or postmortem HRCT and correlated them with pathologic findings. RESULTS: Nine areas of the lung that showed increased attenuation without traction bronchiectasis were associated with either the exudative (n = 5) or early proliferative (n = 4) phase of AIP. Eleven areas of increased attenuation with traction bronchiectasis were associated with either the proliferative (n = 4) or fibrotic (n = 7) phase of AIP. Honey-combing, observed in one area of the lung, corresponded to restructuring of distal airspaces and dense interstitial fibrosis. Six spared areas, within or adjacent to areas of increased attenuation, showed pathologic findings of the exudative phase. CONCLUSION: HRCT findings were not specific for the pathologic findings in our patients with AIP. Nevertheless, the findings of traction bronchiectasis in areas of increased attenuation suggested the proliferative or fibrotic phase.

Presence of poorly stained myocytes in acute myocarditis predicts improvement in cardiac function.

Histological findings in the acute phase of myocarditis were evaluated as a prediction of hemodynamic state in the chronic phase in 20 patients with clinical and pathological diagnoses of myocarditis who were followed up with echocardiography for at least 1 year. Endomyocardial biopsy samples were obtained from the left ventricle within 1 year of the onset of symptoms. Azan-Mallory staining was performed on the myocytes, which were categorized as either well stained or poorly stained. The point counting method was used to determine the fraction of each type. The improvement in ejection fraction within 1 year correlated significantly with the fraction of poorly stained myocytes (r = 0.46, p < 0.05). The ejection fraction at biopsy was negatively correlated with the volume fraction of well stained myocytes (r = -0.64, p < 0.01). The staining condition of myocytes may be useful in predicting the hemodynamic recovery of patients with myocarditis.

Suppressive effect of anti-alpha 1-antichymotrypsin serum on pulmonary fibrosis induced by phorbol myristate acetate in vivo.

BACKGROUND: PMA induces pulmonary fibrosis in the rabbit (1). Pulmonary fibrosis induced by PMA occurs in the alveolar wall and has the same pattern as idiopathic pulmonary fibrosis (IPF)(2), so this system can be used as an animal model for IPF. PMA also increases the content of alpha-1-antichymotrypsin (ACT) in cultured alveolar macrophages of bronchoalveolar lavages (BAL), and dexamethasone inhibits this PMA-induced increase (3). Here we investigated the role of ACT in pulmonary fibrosis induced by PMA. EXPERIMENTAL DESIGN: Rabbits were treated intratracheally for 6 days with saline, dimethyl sulphoxide (DMSO) used as a solvent of PMA, PMA dissolved in DMSO or PMA plus anti-ACT rabbit serum. BAL samples were obtained. ACT in cell pellet and cell-free fluid of BAL were assayed by radioimmunoassay. Sections of the lung were examined histologically by a point count method. The ratio of fibrosis to elastosis (fibrotic ratio) was evaluated for each rabbit by the ratio of total points of collagen stained by the Azan-Mallory method to those of elastic fiber stained by the Elastica van Gieson method. Hydroxyproline (HP) was assayed biochemically, and the amount of HP in the alveolar wall for each rabbit was calculated using the assayed values of HP and the ratio of histologic collagen points in the alveolar wall to those in the lung tissue by a point count method. RESULTS: The fibrotic ratio of the PMA group increased fourfold compared with that of the saline group. The ratio of the PMA plus anti-ACT group decreased and was similar to that of the saline group. The ratio of the DMSO group was about two times as much as that of the saline or the PMA plus anti-ACT groups. The calculated amount of hydroxyproline in the alveolar wall of the PMA group increased and was approximately 1.5-fold compared with that of the saline group. The amount of HP of the PMA plus anti-ACT group decreased and was similar to that of the saline group. In the BAL, the amount and the percentage of ACT in cell pellet per macrophage of the PMA group increased more than those of the saline and DMSO groups. The amount and percentage of the PMA plus anti-ACT group were significantly less than those of the PMA group. Those of the DMSO group were similar to those of the saline group. CONCLUSIONS: These findings suggest that anti-ACT has a suppressive effect on pulmonary fibrosis induced by PMA and that ACT is important in the PMA model of pulmonary fibrosis.

Clear cell adenocarcinoma of the female urethra showing positive staining with antibodies to prostate-specific antigen and prostatic acid phosphatase.

A case of clear cell adenocarcinoma arising from the female urethra is described. Histologically, solid and glandular areas consisted of clear cells. The tumor cells stained positively with antibodies to prostate-specific antigen and prostatic acid phosphatase, suggesting that the clear cell adenocarcinoma arises from the female paraurethral duct, rather than embryonic remnants.

Solitary glomus tumour with mucinous degeneration.

Four cases of solitary glomus tumour are reported, three of the angiomatous type, and one of the epitheliomatous type. In all cases, mucinous degeneration was seen, the extent of which correlated with the number of glomus cells.

New approach to the estimation of the extent of myocardial fibrosis in patients with dilated cardiomyopathy: use of signal-averaged electrocardiography.

To determine whether the extent of myocardial fibrosis in dilated cardiomyopathy could be estimated noninvasively, signal-averaged electrocardiograms were recorded in 32 patients with dilated cardiomyopathy, followed by left ventricular endomyocardial biopsy. The root mean square voltage for the last 40 msec (V40), the duration of the filtered QRS complex (fQRSd) and the duration of low amplitude signals < 40 microV (LAS) were obtained by signal-averaged electrocardiography. The extent of fibrosis in all biopsy samples was measured by the point-counting method. The extent of myocardial fibrosis closely correlated with fQRSd (r = 0.623, p < 0.001), LAS (r = 0.570, p < 0.001), and V40 (r = -0.355, p < 0.05). When fibrosis was classified into intercellular and interfascicular types, the extent of intercellular fibrosis more closely correlated with fQRSd (r = 0.695, p < 0.0001), LAS (r = 0.640, p < 0.0001), and V40 (r = -0.533, p < 0.005). These results suggest that signal-averaged electrocardiograms might be useful for estimation of the extent of myocardial fibrosis, especially intercellular fibrosis in patients with dilated cardiomyopathy.

Clinicopathology of kidneys from brain-dead patients treated with vasopressin and epinephrine.

Studies were made on the biochemical and pathological conditions of kidneys of 20 brain-dead patients who were maintained for 0 to 48 days after brain death by administration of vasopressin and epinephrine. Twenty specimens were obtained by percutaneous biopsy or at autopsy. The biochemical and pathological degrees were compared with those on the day of brain death (day 0). Biochemical tests on day 0 indicated that they showed the diuretic phase of prerenal failure, and then glomerular hyperemia was extensive. Renal function recovered on day 1 and remained almost normal during the 14 day period. Their urine retained high levels of sodium and osmolarity for days 0 to 14, with mild hyponatremia and hypo-osmolarity of the plasma. Tubulointerstitial nephritis gradually became extensive. There was no significant change in the degrees of mesangial widening, mesangial cell proliferation or hyalinosis. Arterial intimal proliferation was gradually extensive after day 3 and glomerular endothelial proliferation was gradually extensive after a week. Brain-dead patients have been mostly reported to develop diabetes insipidus, but our brain-dead patients did not show any manifestation of this disease. We suggest that constant natriuresis and continuing high level of urine osmolarity might have been caused by prerenal renal failure, brain death followed by neurogenic impairment, high level of serum vasopressin, or interstitial nephritis.

Metastatic pulmonary calcification: early detection by high-resolution CT.

A 41-year-old man with a renal transplant was admitted with cough, fever, and dyspnea. Although chest radiography was normal, high-resolution CT demonstrated small hazy round opacities in the centrilobular regions throughout both lungs. The biopsy specimen revealed metastatic calcification in the alveolar septa and the walls of the bronchioles and arterioles. High-resolution CT may be useful for the early detection of metastatic pulmonary calcification when plain radiography is negative and therapy has the potential to reverse the process.

Which subgroup of patients with dilated cardiomyopathy would benefit from long-term beta-blocker therapy? A histologic viewpoint.

OBJECTIVES: The purpose of this study was to elucidate whether the effectiveness of long-term beta-blocker therapy could be predicted before this therapy is started. BACKGROUND: Long-term beta-blocker therapy has recently been reported to provide a favorable effect in treatment of congestive heart failure due to dilated cardiomyopathy. METHODS: Several measurements including histologic variables before administration of metoprolol were retrospectively compared among 18 good responders (showing improvement of at least one New York Heart Association functional class or an increase in ejection fraction > or = 0.10 12 months after drug administration) and 12 poor responders without such improvement. RESULTS: Although there were no significant differences between the two groups in age, gender, functional class, heart rate, blood pressure, pulmonary capillary wedge pressure, cardiac index, left ventricular end-diastolic dimension and ejection fraction, percent fibrosis estimated by the point-counting method in endomyocardial biopsy specimens was significantly lower in good than in poor responders (7.6 +/- 5.7 vs. 14.2 +/- 9.7%, p < 0.05). Moreover, when the types of fibrosis were classified as interfascicular and intercellular by the dominance of counted points, there were 13 cases of interfascicular fibrosis and 5 cases of intercellular fibrosis in good responders and 1 case of interfascicular fibrosis and 11 cases of intercellular fibrosis in poor responders (p < 0.001, sensitivity 72%, specificity 91%, predictive accuracy 80%). These results suggest that improvement with long-term beta-blocker therapy may be more likely to occur in patients with less myocardial fibrosis, with interfascicular fibrosis the dominant type. CONCLUSIONS: The extent and type of fibrosis may be important factors in the prediction of the effectiveness of long-term beta-blocker therapy for dilated cardiomyopathy.

Thyroid nodules associated with Hashimoto thyroiditis: assessment with US.

Sonographic findings in 109 thyroid nodules in 104 patients with Hashimoto thyroiditis were retrospectively analyzed. Sixty patients underwent ultrasound (US)--guided fine-needle aspiration (FNA) biopsy (65 nodules, 24 palpable, 27 surgically confirmed), 14 of whom also underwent palpation-guided FNA (14 nodules, all palpable, all surgically confirmed). Forty-four patients (44 nodules, 25 palpable) underwent diagnostic US followed up with surgery. US-guided FNA helped differentiate between benign (n = 11) and malignant (n = 16) diseases (sensitivity, 100%). Two papillary carcinomas were falsely diagnosed as Hashimoto thyroiditis with palpation-guided FNA. Eight malignancies were not palpable, and correct diagnosis was obtained with US-guided FNA. Hyperechoic nodules were usually benign, and isoechoic nodules had a low frequency (13%) of malignancy. Most carcinomas were found in hypoechoic masses, and almost all lymphomas were found in markedly hypoechoic masses. Lymphoma was indistinguishable from pseudotumor in Hashimoto thyroiditis or adenomatous hyperplasia at US. US-guided FNA is helpful in making the histologic diagnosis in thyroid nodules associated with Hashimoto thyroiditis. US-guided FNA is clinically beneficial because it can help select patients who need surgery, avoiding unnecessary surgery for patients with nonneoplastic disorders.

CT findings in lymphangitic carcinomatosis of the lung: correlation with histologic findings and pulmonary function tests.

The purpose of this study was to analyze the CT findings in lymphangitic carcinomatosis and to determine how the abnormalities seen on CT correlated with histologic findings and the results of pulmonary function tests. Accordingly, we reviewed CT findings in 20 proved cases and correlated them with histologic findings and with results of pulmonary function tests (available in 11). Special attention was given to the extent and degree of thickening of the peripheral and/or axial interstitium as seen on CT. In 15 of 20 patients, CT scans showed marked thickening of axial interstitium and subtle or no thickening of peripheral interstitium (four diffuse and 11 localized). In three cases, CT showed marked thickening of both axial and peripheral interstitium (two diffuse and one localized). In two cases, CT showed marked thickening of peripheral interstitium and subtle or no thickening of axial interstitium (one diffuse and one localized). These CT findings correlated with the pathologic findings. Marked impairment of vital capacity and alveolar-arterial oxygen gradient was observed in three patients (one with diffuse and peripheral interstitial thickening and two with diffuse and both peripheral and axial interstitial thickening). We conclude that CT findings in patients with lymphangitic carcinomatosis are variable and that marked impairment of pulmonary function occurs in patients with diffuse and peripheral interstitial thickening. Marked impairment of pulmonary function can be predicted from CT findings.

CT and MR appearances of parotid pseudotumors in Sjögren syndrome.

The radiologic findings in eight patients with parotid pseudotumors associated with Sjögren syndrome (CT in eight; MRI in two) were retrospectively analyzed and compared with the findings in three cases with malignant lymphomas. Diagnosis of pseudotumor was obtained by surgery in six cases and by fine-needle aspiration biopsy and radiologic follow-up in the remaining cases. Six cases (75%) had advanced disease and the remaining had early disease. Both solid (75%) and cystic (38%) masses were seen in the patients with pseudotumors. The masses were solitary in 25%, multiple in 75%, unilateral in 25%, and bilateral in 75%. All three lymphomas were solid masses. The lymphomatous masses were not reliably distinguished from the solid pseudotumors.