Spiral Ct with Three-Dimensional and Multiplanar Reconstruction in the Diagnosis of Anterior Chest Wall Joint and Bone Disorders

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1 Acta Radiologica ISSN: (Print) (Online) Journal homepage: Spiral Ct with Three-Dimensional and Multiplanar Reconstruction in the Diagnosis of Anterior Chest Wall Joint and Bone Disorders A. G. Jurik & J. Albrechtsen To cite this article: A. G. Jurik & J. Albrechtsen (1994) Spiral Ct with Three-Dimensional and Multiplanar Reconstruction in the Diagnosis of Anterior Chest Wall Joint and Bone Disorders, Acta Radiologica, 35:5, To link to this article: Published online: 04 Jan Submit your article to this journal Article views: 47 Full Terms & Conditions of access and use can be found at

2 Actu Rudiologica 35 (1994) Fasc. 5 Priiited in Denmurk. All rights reserved Copyright 0 Acta Radiologica 1994 ACTA R A D I 0 LO G IC A ISSN FROM THE DEPARTMENT OF DIAGNOSTIC RADIOLOGY R, MUNICIPAL HOSPITAL, UNIVERSITY OF AARHUS, AARHUS, DENMARK. SPIRAL CT WITH THREE-DIMENSIONAL AND MULTIPLANAR RECONSTRUCTION IN THE DIAGNOSIS OF ANTERIOR CHEST WALL JOINT AND BONE DISORDERS A. G. JURIK and J. ALBRECHTSEN Abstract Twenty-seven patients with symptoms or clinical findings suggesting joint or bone disorders of the anterior chest wall (ACW) were evaluated by spiral CT with 3-dimensional (3-D) and multiplanar reconstructions. Preceding conventional ACW tomography was performed in 10 patients. ACW joint and bone changes were visualized more adequately by coronal 2-D reconstructions based on spiral CT than by conventional tomography. In addition, nonossified costal cartilages and soft tissue lesions were demonstrated. 3-D reconstructions sometimes added information, especially in patients with fracture and dislocation. Key words: Sternum, clavicle; sternoclavicular joint; CT. The recent development of spiral CT, with the capability of performing contiguous I-s tube rotation coupled with contiguous patient transport, has enabled volumetric acquisition during a single breath-holding period. It is thereby possible to acquire contiguous data without the respiratory disturbances that frequently degrade the image quality of 3-dimensional (3-D) and multiplanar reconstructions. Radiographic visualization of anterior chest wall (ACW) bone and joint disorders can be achieved by multidirectional tomography (5, 9), but this modality does not demonstrate soft tissue changes. Such changes can be visualized by CT (2, 3, 8, 9), but due to the orientation of ACW joints, transverse CT slices may be inadequate with regard to joint disorders, especially those of the manubriosternal joint. Supplementary multiplanar reconstructions will relieve this problem, but are, if based on serial CT images, jagged due to respiratory movements. Spiral CT during a single breath- holding period will eliminate respiratory movement and thereby improve reconstructions. The aim of the present report was to evaluate spiral CT with multiplanar and 3-D reconstructions in the diagnosis of ACW disorders. Material and Methods Twenty-seven patients, 24 women and 3 men (aged years, mean 44 years) with ACW complaint or clinical findings suggesting joint or bone disease were evaluated by spiral CT. Pain and swelling of the sternoclavicular and/or manubriosternal joint occurred in 14 patients; 5 patients had sternal pain and/or swelling with increased scintigraphic activity, and 5 had posttraumatic pain and swelling. Prominence of costal cartilages occurred in 2 patients, and one patient had pain and swelling of the clavicle. The spiral CT was performed with a Somatom Plus-S scanner (Siemens). The patients were placed supine with the arms above the head. After a scout view, a 9- to 12-cmlong scan volume was performed during breath-holding, located according to the diagnostic problem. The parameters were 1-s tube rotation, 120 kv and 165 to 210 ma; the collimation was set at 3 mm, and the table speed at 3 mm/s. After the acquisition, 3-mm transverse sections (32-42 slices) were made with a field of view of 15 cm and the standard reconstruction algorithm (Siemens). Afterwards the image volume was reconstructed into 1-mm trans- Accepted for publication 14 February

3 ANTERIOR CHEST WALL JOINT AND BONE DISORDERS BY SPIRAL CT 469 Fig. I. Osteoarthrosis of the right sternoclavicular joint in a 51- year-old woman with intermittent pain and swelling for a period of 7 months. Coronal 2-D reconstruction showing slight joint space narrowing, subchondral sclerosis and cyst formation, and osteophyte formation at the inferior margin of the clavicle. Fig. 2. Arthritis of the manubriosternal joint in a 22-year-old man with pain and swelling for 5 months. Coronal 2-D reconstruction demonstrating erosive changes of the manubriosternal joint. verse sections ( slices), which were used for 3-D reconstruction. Threshold values ranged from 140 to 160 Hounsfield units. Secondary multiplanar reconstructions were made based on the displayed 3-D figure by a reformatting program (Siemens). The amount of time required to perform the 3-D and multiplanar reconstructions was about 30 min. A preceding 8" elliptical p.a. ACW tomography was performed in the first 10 patients evaluated, including 5 patients with malignant disorders, 3 with posttraumatic pain and/ or swelling, one with anomaly, and one with pustulotic arthroosteitis. Due to ethical reasons additional conventional tomography was not performed in the subsequent 17 patients. Fig. 3. Pustulotic arthroosteitis in a 47-year-old woman with ACW discomfort for a period of 10 years and an osseous prominence especially on the right side. a) Conventional tomogram demonstrating nearly diffuse sclerosis and hyperostosis of the manubrium sterni with new bone formation, especially on the right side. b) Coronal 2-D and c) 3-D reconstructions clearly visualizing a continuous hyperostotic osseous plate on the right side due to new bone formation in addition to ossification and hyperostosis of the first costal cartilage.

4 470 A. G. JURIK AND J. ALBRECHTSEN Fig. 5. Metastasis in a 32-year-old woman with breast carcinoma and increased scintigraphic activity in the lower part of the sternal body. 3-D display and 2-D lateral reconstruction demonstrating an intramedullary destruction in the lower part of the sternal body with a small cortical breakthrough. Fig. 4. Sequelae of clavicular fracture in a 43-year-old woman involved in a traffic accident 2 years earlier. a) Transverse slice and b) 3-D reconstruction demonstrating a displaced nonunion fracture in the medial part of the left clavicle. In all patients a thorough clinical examination was performed in addition to laboratory and further radiographic examinations necessary to make a diagnosis. Verification of the diagnosis by operation or biopsy was obtained in 6 patients. Results Radiographic changes compatible with osteoarthrosis of the sternoclavicular joint(s) occurred in 9 patients (Fig. I). Five patients had bilateral, 5 right-sided and 2 left-sided changes. Seven of the 9 patients had degenerative lesions of other joints. Five patients had rheumatologic disorders, 3 in the form of seronegative arthritis of the sternoclavicular or manubriosternal joint (Fig. 2) as part of generalized arthritis, in 2 associated with HLA-B27. One woman had pustulotic arthroosteitis with diffuse sclerosis and hyperostosis of the manubrium sterni better visualized by oblique coronal and 3-D reconstructions than by conventional tomography (Fig. 3). One child had a sclerotic and hyperostotic clavicular lesion as part of chronic recurrent multifocal osteomyelitis which was well visualized by CT with reconstructions. Fracture and/or dislocation or sequelae of such occurred in 5 patients. The changes could be visualized on conventional tomograms (3 patients), transverse CT images and coronal reconstructions, but 3-D display added information about the degree of displacement (Fig. 4). Five patients had malignant sternal destruction with increased scintigraphic activity. In 4 patients with metastasis from breast carcinoma, the destructions were not detectable by conventional tomography, probably because they were mainly in an intramedullary location (Fig. 5). In one patient with myelomatosis and a technically insufficient tomography due to pain when placed in the prone position, the transverse CT images demonstrated extensive sternal destruction and a soft tissue mass, but the extent of osseous breakthrough was best visualized by 3-D display. Congenital abnormalities or variants occurred in 3 patients, in one of whom a preceding tomography was performed, but the final diagnosis was obtained by CT with reconstructions (Fig. 6). One girl had a persisting sternal

5 ANTERIOR CHEST WALL JOINT AND BONE DISORDERS BY SPIRAL CT 47 1 Fig. 6. Congenital anomaly in a 27iyear-old woman with osseous prominence at the sternoclavicular joints for some years, in addition to pain in the region of the left sternoclavicular joint for 3 months. a) Conventional tomogram demonstrating osteoarthrosis of the sternoclavicular joints most pronounced at the left side. b) 3-D and c) coronal 2-D reconstructions clearly demonstrating congenital anomaly with the second costal cartilages joining the middle of the manubrium sterni. The first ribs (not shown) were rudimentary and did not reach the ACW. foramen (Fig. 7), and one boy chest asymmetry as part of scoliosis with prominence of costal cartilage. 3-D reconstruction was useful for visualizing both the scoliosis and the concomitant ribs and cartilage bending with twisting of the sternum. Osseous resolution was nearly as good by CT as by conventional tomography (Figs 3 and 6), and the possibility of oblique coronal reconstructions was a great advantage in the visualization of the joints. addition, CT visualized Fig. 7. Congenital variant in a 13-year-old girl with ACW discomfort for a period of 2 months. a) 3-D and b) coronal 2-D reconstructions 'Oft tissue and noncalcified cartilages demonstrating persistence ofa foramen in the sternal body (sequelae - an advantage not only in patients with malignancies, but of great vessels passing through the fetal cartilaginous adage). The also in the patients with congenital abnormalities/variants examination was performed by adding two 9-cm volume images. (Fig. 2).

6 412 A. G. JURIK AND J. ALBRECHTSEN Discussion The ACW may be difficult to visualize by conventional radiography. Many special projections have been proposed to minimize the effect of overprojecting structures (1, 4, 6), but adequate conventional films are often difficult to obtain and interpret. ACW bones and joints can be sufficiently visualized by the use of multidirectional, conventional tomography in the prone position, but soft tissue structures are not visualized by this modality (5, 9). CT is an excellent technique for visualization of ACW bones, although the spatial resolution regarding bone structures is somewhat lower than that of conventional tomography (2,3, 8,9). An advantage of CT is that it eliminates overlap and in addition provides superior soft tissue contrast. Visualization of ACW joints, especially the manubriosternal joint may, however, be difficult on transverse CT images. The present analysis shows the advantage of spiral CT with multiplanar and 3-D reconstruction in the visualization of osteoarticular changes. The lower spatial resolution at coronal reconstructions compared with conventional tomograms did not diminish their diagnostic value, and the possibility of obtaining oblique coronal reconstructions, visualizing both the sternoclavicular and manubriosternal joints, was a great advantage compared with conventional tomography. The use of spiral CT during breath-holding has the advantage of eliminating respiratory movements. In addition, it is possible to make transverse slices thinner than the collimation. In the present study 1-mm sections were made based on an acquisition with a collimation of 3 mm and a table speed of 3 mm/s. The 3-D display, and thereby the reformatted multiplanar reconstructions, are often better when based on 1-mm sections than thicker slices (7). The resolution of 1 -mm transverse slices based on 3-mm spiral CT can, however, be insufficient for adequate visualization of soft tissue structures, and it is therefore necessary also to perform transverse slices with a thickness corresponding to the collimation. The consequence of this is an increased time consumption, but the technique has the advantage of minimizing the radiation dose compared with that obtained by acquisition of serial I-mm slices. The dose given corresponds to that of 3-mm slices. When CT is performed with a relatively low ma-value ( mas) it often results in smaller surface doses to the patient than doses given by conventional tomography. In addition, spiral CT is more convenient for the patient because it usually lasts less than one minute. It is thus proposed that conventional ACW tomography, when possible, is replaced by spiral CT. Request for reprints: Dr. Anne Grethe Jurik, Department of Diagnostic Radiology R, Aarhus Kommunehospital, DK-8000 Aarhus C, Denmark. REFERENCES 1. ABEL M. S.: Symmetrical anteroposterior projections of the sternoclavicular joints with motion studies. Radiology 132 (1979), DESTOUET J. M., GILULA L. A,, MURPHY W. A. & SACEL S. S.: Computed tomography of the sternoclavicular joint and sternum. Radiology 138 (1981), HATFIELD M. K., GROSS B. H., GLAZER G. M. & MARTEL W.: Computed tomography of the sternum and its articulations. Skeletal Radiol. 11 (1984), HOBBS D. W.: Sternoclavicular joint. A new axial radiographic view. Radiology 90 (1968), JURIK A. G.: Seronegative anterior chest wall syndromes. A study of the findings and course at radiography. Acta Radiol. 33 (1992), Suppl KATTAN K. R.: Modified view for use in roentgen examination of the sternoclavicular joints. Radiology 108 (1973), NEY D. R., FISHMAN E. K., KAWASHIMA A., ROBERTSON D. D. & SCOTT W. W.: Comparison of helical and serial CT with regard to three-dimensional imaging of musculoskeletal anatomy. Radiology 185 (1992), STARK P.: Computed tomography of the sternum. Crit. Rev. Diagn. Imaging 27 (1987) VOCEL H., NACELE B. & HELLER M.: Rontgenbefunde des Sternum. Z. Orthop. 123 (1985), 213.