| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
1
Department of Radiology, Vancouver General Hospital and University of British
Columbia, 855 W. 12th Ave., Vancouver, B. C., V5Z 1M9, Canada.
2
Department of Radiology, University of Michigan Hospitals, 1500 E. Medical
Center Drive, Ann Arbor, MI 48109-0326.
3
Department of Radiology, University of Washington, 1959 N.E. Pacific St.,
Seattle, WA 98195.
Received June 18, 1999;
accepted after revision August 11, 1999.
Address correspondence to N. L. Müller.
Abstract
 Top Abstract IntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
MATERIALS AND METHODS. The CT scans of 12 patients with talcosis (seven men, five women), 33-54 years old (mean age, 44 years), were analyzed retrospectively. Seven patients had abused methylphenidate; five patients had no history of abuse. The diagnosis of talcosis was made histologically in 11 patients and at funduscopy in one patient. CT was performed with 1 - to 1.5-mm collimation (n = 10 patients) or 5- to 10-mm collimation (n = 2).
RESULTS. The predominant abnormalities seen on CT consisted of a diffuse fine nodular pattern (n = 2), a combination of nodules and lower lobe panacinar emphysema (n = 3), and ground-glass attenuation (n = 2). Emphysema was the only abnormality seen in the remaining five patients (lower lobe panacinar, n = 4; upper lobe centrilobular, n = 1). No significant difference in the prevalence of nodules and ground-glass attenuation was seen between the methylphenidate and non-methylphenidate groups. Lower lobe panacinar emphysema was more common in methylphenidate abusers (six [86%] of seven patients) than in non-methylphenidate drug abusers (one [20%] of five, p < 0.05, Fisher's exact test).
CONCLUSION. The CT manifestations of talcosis consist of a fine micronodular pattern, ground-glass attenuation, and emphysema. A significantly increased prevalence of lower lobe panacinar emphysema is seen in IV drug addicts who abuse methylphenidate.
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
IV drug abusers who develop talcosis experience progressive dyspnea and symptoms resembling chronic obstructive pulmonary disease. The chest radiographic manifestations of talcosis have been previously described [2, 3]. To our knowledge, only two studies describing the CT features of talcosis exist; each examines only three patients with CT [3, 4]. In addition, IV abuse of methylphenidate (Ritalin; Novartis Pharmaceuticals, Dorval, Quebec, Canada) has a tendency to cause severe panacinar emphysema, predominantly in the lower lobes [3]. This pattern resembles the emphysema described in patients with alpha1-antiprotease deficiency.
The aim of this study was to assess the CT appearance of talcosis associated with IV abuse of oral medication in a relatively large number of patients and to compare the findings in talcosis associated with Ritalin with those seen with other drugs.
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
The diagnosis of pulmonary talcosis was made histologically in 11 patients by either autopsy (n = 2), lung volume reduction surgery for treatment of emphysema (n = 2), lung transplantation for endstage respiratory failure (n = 3), transbronchial biopsy (n = 3), or open lung biopsy (n = 1). In one patient, the diagnosis of talcosis was made on the basis of an appropriate clinical history and chest radiographic findings and was confirmed at fundus-copy, which revealed birefringent particles consistent with talc emboli in the retinal vessels. This patient was a 54-year-old woman who gave a 12-year history of IV abuse of heroin and methadone. Chest radiographs 7 years apart showed progression of a fine nodular pattern and perihilar conglomerate masses.
CT Scans
The patients were examined with either a 9800 (n = 6) or HiSpeed
Advantage scanner (n = 6) (both by General Electric Medical Systems,
Milwaukee, WI). All scans were performed at end-inspiration. Ten patients had
thin-section CT with 1- to 1.5-mm collimation at 10-mm intervals. Two patients
had conventional CT with a slice thickness of 10 (n = 1) or 5 mm
(n = 1).
All thin-section CT images were reconstructed with a high-spatial-frequency algorithm (high-resolution CT). The lung windows were photographed at a window level of -450 to -700 H and a window width of 1000-2000 H. The mediastinal windows were imaged at a window level of 20-40 H, and a window width of 350-500 H.
Radiologic Evaluation
The CT scans were assessed randomly and independently by two observers for
nodularity, conglomerate masses, ground-glass attenuation, and emphysema. In
cases of discrepancy between the observers, the final imaging features were
determined by consensus.
The lungs were assessed for the presence, size, number, and distribution of nodules. Conglomerate masses were defined as focal parahilar opacities, measuring greater than 1 cm, associated with loss of lung volume and architectural parenchymal distortion [4, 5]. The presence or absence of high attenuation equivalent to that of calcium in areas of conglomeration was recorded. Ground-glass attenuation was defined as a hazy increase in lung opacity that was not associated with obscuration of underlying vessels [5].
Emphysema was defined as an area of low attenuation with associated arterial deficiency [6, 7]. The emphysema was further described as either centri-lobular or panacinar. Centrilobular emphysema was identified by the presence of localized areas of low attenuation near the center of secondary pulmonary lobules and interspersed with regions of healthy lung [6, 7]. Panacinar emphysema was defined by the presence of widespread areas of low attenuation without small focal areas of lucency [6, 7]. The distribution of the emphysema was assessed for lobar predominance and the severity was indicated subjectively as involving less than 25%, 25-50%, or greater than 50% of the lung volume.
Statistical Analysis
Interobserver agreement was assessed with the kappa statistic
[8]. Comparison between the
prevalence of abnormal CT findings in the patients with known IV Ritalin abuse
and in patients without a history of Ritalin abuse was performed with the
Fisher's exact test [8].
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
|
Conglomerate masses were seen in three (25%) patients, two Ritalin abusers and one non-Ritalin abuser (Fig. 2A,2B,2C). The conglomerate masses were located in a perihilar distribution. Areas of high attenuation equivalent to that of calcium were present in two of the three patients with conglomerate masses. All three patients with conglomerate masses also had a diffuse fine-nodular pattern. Two of the three patients, both Ritalin abusers, had lower lobe panacinar emphysema.
|
|
|
Ground-glass attenuation was identified in seven patients although it was a major finding in only two of these patients (Fig. 3). In the remaining patients, the attenuation resulted from a confluence of micronodules.
|
Emphysema was identified in 10 (83%) of 12 patients. Six patients had CT findings characteristic of panacinar emphysema, two had centrilobular emphysema, and two had both centrilobular emphysema in the upper lobes and panacinar emphysema in the lower lobes. Centrilobular emphysema involved mainly the upper lobes in all patients, whereas the panacinar emphysema involved mainly the lower lobes in seven (88%) of the eight patients. In one patient, severe emphysema was present in the upper but not in the lower lobes. The appearance on CT was considered most consistent with panacinar emphysema. However, this patient had a 60-pack-year history of smoking, and the upper lobe emphysema presumably was centrilobular rather than panacinar. The proportion of lung volume affected by emphysema was less than 25% in three patients, between 25% and 50% in three, and greater than 50% in four.
Six (86%) of the seven patients who predominantly abused IV Ritalin had emphysema (Fig. 4A,4B). Five of these patients had CT findings suggestive of panacinar emphysema affecting the lower lobes, one patient had both panacinar emphysema in the lower lobes and centrilobular emphysema in the upper lobes, and one had only centrilobular emphysema in the upper lobes. Four (67%) of six patients in the non-Ritalin group had evidence of emphysema on CT. One had centrilobular emphysema in the upper lobes, one had panacinar emphysema in the upper lobes, and one had both centrilobular emphysema in the upper lobes and panacinar emphysema in the lower lobes. A significant difference was seen in the prevalence of lower lobe panacinar emphysema in patients with Ritalin abuse (6/7 patients) compared with that of the other patients (1/5, Fisher's exact test, p < 0.05).
|
|
In summary, the predominant abnormalities on CT consisted of a diffuse fine nodular pattern (n = 1), a combination of nodules and conglomerate masses (n = 1), lower lobe panacinar emphysema (n = 4), a combination of nodules and lower lobe panacinar emphysema (n = 3), ground-glass attenuation (n = 2), and upper lobe centrilobular emphysema (n = 1). In five patients emphysema was the only finding; four of these were Ritalin abusers.
A high degree of interobserver agreement was found in the interpretation of the images. The kappa value was 0.87 for lung nodularity and 0.62 for the diagnosis of emphysema. Both observers agreed in the interpretation of all three cases with conglomerate masses, in both cases with predominantly or exclusively ground-glass attenuation, and in the predominant lower lobe distribution of the emphysema present in six Ritalin abusers.
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
In our study, the main manifestation of talcosis was the presence of innumerable nodules measuring 1 mm or less in diameter, a finding seen in five of the 12 patients. Three of these five patients also had conglomerate masses. Two of the three patients had areas of high attenuation resembling calcification in the conglomerate masses. Similar findings were described in two previous studies [3, 4]. In areas where the small nodules were most numerous, the appearance resembled ground-glass attenuation. However, two patients had ground-glass attenuation without any visible nodularity. Although most patients were smokers and had emphysema, a predominantly lower lobe distribution of panacinar emphysema was seen almost exclusively in Ritalin abusers.
Obstructive lung disease in IV drug abusers is uncommon, but precocious severe emphysema was noted in IV Ritalin abusers [10,11,12]. Schmidt et al. [10] studied seven young IV Ritalin abusers with profound obstructive lung disease and described the pathologic basis of the severe chronic airways limitation. All seven patients had severe panacinar emphysema involving mainly the lower lobes without upper lobe conglomerate masses or bulla formation. The distribution and type of emphysema resembled that of alpha1-antiprotease deficiency although no evidence of this disease existed in any of their patients. In another study of 21 patients with obstructive pulmonary disease associated with IV Ritalin abuse, the abnormal radiographic finding consisted of basilar emphysema [3]. This finding was confirmed in three patients on CT. The pathogenesis of the lower lobe panacinar emphysema was not determined in these two studies. Cigarette smoking was considered unlikely to be the causative agent because this most frequently leads to upper lobe centrilobular emphysema. Therefore, it was postulated that the presence of panacinar emphysema may relate directly to the effects of either IV talc or IV Ritalin [10]. In the current study, panacinar emphysema in the lower lobes was detected in six (86%) of seven patients who predominantly abused IV Ritalin, and in only one (20%) of five patients who did not. This difference supports the hypothesis that Ritalin itself may be the primary causal agent.
Our study has several limitations. The patients were selected retrospectively from five centers. Therefore, different CT protocols had been used and thin-section CT was not performed in two patients, both of whom had lower lobe panacinar emphysema. IV drug users often abuse multiple drugs simultaneously and smoke heavily. Both habits could result in a mixed pattern of changes detected on CT. One patient did not have the diagnosis of talcosis confirmed pathologically. However, this patient had a significant history of IV drug abuse and had birefringent particles at funduscopy, a diagnostic finding of talc retinopathy.
In summary, we detected four main patterns of abnormality on the CT scans of patients with talcosis related to the IV abuse of oral medications. The patterns consisted of a fine micronodular pattern, conglomerate parahilar masses on a background of micronodularity, ground-glass attenuation, and emphysema. These patterns frequently appeared in combination. No significant difference in the prevalence of micronodularity or ground-glass attenuation was found between IV drug abusers who did or did not abuse Ritalin. Lower lobe panacinar emphysema was found more frequently in IV drug addicts who abused Ritalin.
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
This article has been cited by other articles:
|
|
 |
|
  I Petrache, K Diab, K S Knox, H L Twigg III, R S Stephens, S Flores, and R M Tuder HIV associated pulmonary emphysema: a review of the literature and inquiry into its mechanism Thorax, May 1, 2008; 63(5): 463 - 469. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 D. M. Hansell, A. A. Bankier, H. MacMahon, T. C. McLoud, N. L. Muller, and J. Remy Fleischner Society: Glossary of Terms for Thoracic Imaging Radiology, March 1, 2008; 246(3): 697 - 722. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 I. G. Hagan and K. Burney Radiology of Recreational Drug Abuse RadioGraphics, July 1, 2007; 27(4): 919 - 940. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. S. Restrepo, J. A. Carrillo, S. Martinez, P. Ojeda, A. L. Rivera, and A. Hatta Pulmonary Complications from Cocaine and Cocaine-based Substances: Imaging Manifestations RadioGraphics, July 1, 2007; 27(4): 941 - 956. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Akira, T. Kozuka, S. Yamamoto, M. Sakatani, and K. Morinaga Inhalational Talc Pneumoconiosis: Radiographic and CT Findings in 14 Patients Am. J. Roentgenol., February 1, 2007; 188(2): 326 - 333. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Chong, K. S. Lee, M. J. Chung, J. Han, O J. Kwon, and T. S. Kim Pneumoconiosis: Comparison of Imaging and Pathologic Findings RadioGraphics, January 1, 2006; 26(1): 59 - 77. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. Marchiori, A. S. Souza Jr., T. Franquet, and N. L. Muller Diffuse High-Attenuation Pulmonary Abnormalities: A Pattern-Oriented Diagnostic Approach on High-Resolution CT Am. J. Roentgenol., January 1, 2005; 184(1): 273 - 282. [Full Text] [PDF]
|
|
|
|
|
|
M. B. Gotway, S. R. Marder, D. K. Hanks, J. W. T. Leung, S. K. Dawn, A. D. Gean, G. P. Reddy, P. A. Araoz, and W. R. Webb Thoracic Complications of Illicit Drug Use: An Organ System Approach RadioGraphics, October 1, 2002; 22(90001): S119 - 135. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P. Rodrigues Genta, C. Bastos Valeri, R. Adib Kairalla, V.L. Capelozzi, and C.R. Ribeiro de Carvalho A 44-yr-old male with progressive dyspnoea and dry cough Eur. Respir. J., September 1, 2002; 20(3): 786 - 788. [Full Text] [PDF]
|
|
|
|
|
|
J. G. Ravenel, H. P. McAdams, J. F. Plankeel, K. J. Butnor, and T. A. Sporn Sarcoidosis Induced by Interferon Therapy Am. J. Roentgenol., July 1, 2001; 177(1): 199 - 201. [Full Text] [PDF]
|
|
|
|
|
|
J. Collins, M. J. Hartman, T. F. Warner, N. L. Müller, E. A. Kazerooni, H. P. McAdams, R. M. Slone, and L. A. Parker Frequency and CT Findings of Recurrent Disease after Lung Transplantation Radiology, May 1, 2001; 219(2): 503 - 509. [Abstract] [Full Text]
|
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
