- Email: [email protected]
Application of digital tomosynthesis in diagnosing spinal tuberculosis
Clinical Imaging 40 (2016) 461–464
Contents lists available at ScienceDirect
Clinical Imaging journal homepage: http://www.clinicalimaging.org
Application of digital tomosynthesis in diagnosing spinal tuberculosis Dan Jiao, Dong-yan Yang ⁎, Wen Tian, Hui Wang, Hong-ping Ji Department of Ultrasound, China-Japan Union Hospital of Jilin University, No. 126, Xian-Tai Street, Changchun City, 130021, China
a r t i c l e
i n f o
Article history: Received 17 August 2015 Received in revised form 24 October 2015 Accepted 5 November 2015 Available online xxxx Keywords: Digital tomosynthesis Digital radiology Spinal tuberculosis Image quality Ratios of detection of lesions
a b s t r a c t Objective: To study the value of digital tomosynthesis (DTS) applied in diagnosing spinal tuberculosis. Methods: Images of digital radiology (DR) and DTS were retrospectively analyzed in patients with spinal tuberculosis, and image quality and ratio of detection of lesions were compared. Results: Excellent ratio was higher for DTS images than DR images; ratios of detection of bone destruction, sequestration, and paraspinal abscess were higher for DTS than DR. Conclusions: DTS had better image quality and ratios of detection of lesions and could be applied in diagnosing and following spinal tuberculosis and other spinal conditions such as infections or suspected tumors.
© 2016 Elsevier Inc. All rights reserved.
1. Introduction
2.2. Examination methods
Spinal tuberculosis is the most common in bone and joint tuberculosis [1–3], and it has very high prevalence and morbidity in China [4]. Tuberculosis is routinely diagnosed by digital radiology (DR) combined with tuberculin test, but digital tomosynthesis (DTS) is a new tool in the imaging diagnosis of tuberculosis. DTS has a lower radiation dose compared with Computed Tomography (CT) [5] and higher spatial resolution compared with DR. In the paper, the image quality and detection rates of bone destruction, sequestration, narrowing, or disappearing intervertebral space and paravertebral abscess between DR and DTS were compared, and the aim is to determine the value of DTS applied in diagnosing spinal tuberculosis.
DR was performed with Ysio (Siemens, Germany), and anterior– posterior view and lateral view were adopted. DTS was performed with Sonialvision Satire II (Shimadzu, Japan), using the procedure of TOMOS. The distance was 1100 mm between the X-ray tube and flat panel detector, and the exposure conditions were determined according to the thickness of different locations. The exposure conditions were 85 kV and 50 mAs for anterior–posterior view of the lumbar vertebrae, and 100 kV and 45 mAs for lateral view of the lumbar vertebrae. Postprocessing parameters included range of 100 mm and pitch of 2.0 mm. Seventy-four frames of DTS images were reconstructed, and sharp images were chosen.
2. Materials and methods
2.3. Reading images and evaluating image quality
2.1. Patients
Two radiologists, including a chief physician and an associate chief physician, simultaneously read the images of DR and DTS. Image quality was evaluated, and bone destruction, sequestration, narrowing, or disappearing intervertebral space and paravertebral abscess were detected. The two radiologists should be in agreement after discussion if they had different opinions. The criteria of an excellent image were as follows: (a) the image included the targeted vertebrae completely; (b) the spinal canal and superior and inferior articular process had clear structure and satisfactory contrast in lateral views; (c) the cortical bone had clear display. The criteria of an inadequate image were as follows: (a) the image did not include the targeted vertebrae completely, or its location was not standard, which led to bilateral shadow; or (b) the image deviated from center line and had inadequate exposure,
Fifty-five patients with spinal tuberculosis were enrolled in China– Japan Union Hospital of Jilin University from May 2011 to May 2015. Both DR and DTS were performed in all the patients before surgery, and tuberculosis was confirmed with surgical pathology. These patients included 23 males and 32 females and had a mean age of 40.1 years (6–62 years) and duration of 24.8 months (half a month–10 years). ⁎ Corresponding author. Department of Ultrasound, China-Japan Union Hospital of Jilin University, No. 126, Xian-Tai Street, Changchun City, 130021, China. Tel./fax: +86-4322615087. E-mail address: [email protected] (D. Yang). http://dx.doi.org/10.1016/j.clinimag.2015.11.003 0899-7071/© 2016 Elsevier Inc. All rights reserved.
462
D. Jiao et al. / Clinical Imaging 40 (2016) 461–464
A
B
C
D
Fig. 1. A 45-year-old woman with thoracic three to nine vertebral tuberculosis diagnosed with DTS. DR images: A.1 and A.2 showed (a) increased density in thoracic vertebral body 8 and 9; (b) bone destruction in vertebral body border, narrowing intervertebral space between thoracic vertebrae 8 and 9; and (c) fusiform broadening of the bilateral paravertebral lines. DTS images: A.3 and A.4 showed (a) bone destruction in the anterior border of thoracic vertebral body 3, left border of thoracic vertebral body 4 and 5, superior and inferior border of thoracic 7, 8, and 9; (b) narrowing intervertebral space between thoracic vertebrae 3 and 4, between 4 and 5, between 7 and 8, and between 8 and 9; and (c) fusiform broadening of the bilateral paravertebral lines.
which led to bad display of lesion. Osteoporosis was determined according to cortical thinning and increased radiolucency for DR images.
vertebral bodies were most frequently involved (40 patients). Total of vertebral bodies involved was 160.
2.4. Statistical analysis 3.2. Main DR manifestations of spinal tuberculosis The statistical analysis was performed with the Statistical Product and Service Solutions (SPSS) Version 19.0. The image quality and detection rates of bone destruction, sequestration, narrowing, or disappearing intervertebral space and paravertebral abscess between DR and DTS were compared with chi-square test. Significance was set at Pb 0.05. 3. Results 3.1. Vertebral body involved in lesion The vertebral body involved in lesion included the cervical vertebrae (3 patients), thoracic vertebrae (10 patients), vertebrae of thoracolumbar segment (10 patients), lumbar vertebrae (20 patients), and lumbosacral vertebrae (12 patients). A single vertebral body was involved in three patients, and multiple vertebral bodies were involved in 52 patients. Six vertebral bodies were involved at most (one patient), and two to three
A
B
Bone destruction was detected in 47 patients, and DR images showed (a) osteoporosis and (b) circular, irregular, and vesicant defect. Sequestration was detected in 18 patients, and DR images showed dense shadow with the size of grit or rice in the region of bone destruction. Narrowing or disappearing intervertebral space was detected in 50 patients, and 20 patients among them had mutual embedding vertebral bodies with angular deformity whose borders were coarse and blurred, and meanwhile had changed curvature of the spinal column. Paravertebral abscess was detected in 20 patients, and mottling calcification shadow was detected in five patients among them. DR images of paravertebral abscess showed posterior wall of pharynx abscess for tuberculous cervical spondylitis, fusiform broadening of the paravertebral line for tuberculosis of thoracic spine (shown in Fig. 1), and blur, satiation, and broadening of the psoas major muscle for tuberculosis of lumbar spine.
C
D
Fig. 2. A 26-year-old woman with lumbar three to five vertebral tuberculosis diagnosed with DTS. DR images: B.1 and B.2 showed (a) irregular bone destruction in lumbar vertebral body 3 and 4; (b) collapse and density of lumbar vertebral body 4; and (c) narrowing and disappearing intervertebral space between lumbar vertebrae 3 and 4. DTS images: B.3 and B.4 showed (a) bone destruction in lumbar vertebral body 3 and 4; (b) inhomogeneous reduced density in lumbar vertebral body 5 with multiple destruction regions inside the vertebral body and small patchy sequestrum shadow surrounding the vertebral body; and (c) abscess formation in the bilateral psoas major muscles.
D. Jiao et al. / Clinical Imaging 40 (2016) 461–464
463
A
B
C
D
E
F
Fig. 3. A 47-year-old woman with lumbar 2–sacral 1 vertebral tuberculosis diagnosed with DTS and CT. DR images: C.1 and C.2 showed (a) posterior deformity of the lumbosacral vertebrae; (b) irregular bone destruction in lumbar 3–sacral 1 vertebral body which had no normal morphous and had multiple small sequestrum shadows in localized region; and (c) abscess formation and mottling calcification shadow in the right psoas major muscle. DTS images: C3 and C4 showed (a) bone destruction in lumbar 3–sacral 1 vertebral body; (b) the spinal canal was involved in lesion; and (c) semicircular bone destruction with mild sclerosis in its border in the posterior border of lumbar vertebral body 2. CT images: C5 and C6 confirmed the diagnosis of DTS.
3.3. Main DTS manifestations of spinal tuberculosis Bone destruction was detected in 55 patients. DTS images showed irregular vertebral body, moth-eaten destruction, cavernose destruction, localized osteolytic change, and fragmented change, and most patients had multiple manifestations. Wedging vertebral body was detected in 35 patients (shown in Fig. 2). Patchy or gritty sequestration was detected in 38 patients, and DTS images showed irregular hyperdense shadow. Narrowing or disappearing intervertebral space was detected in 50 patients, and 20 patients among them had mutual embedding vertebral bodies with angular deformity whose borders were coarse and blurred, and meanwhile had changed curvature of the spinal column (shown in Fig. 3). Paravertebral abscess was detected in 35 patients, and gritty and mottling calcification shadow was detected in 8 patients among them (shown in Fig. 3). 3.4. Image quality of DR and DTS The excellent ratio was 83.64% for DR images and 100% for DTS images. The excellent ratio was higher for DTS images than for DR images (χ2=7.745, P=0.005) (Table 1). 3.5. Ratios of detection of bone destruction, sequestration, narrowing, or disappearing intervertebral space and paravertebral abscess of DR and DTS The ratios of detection of DR of bone destruction, sequestration, narrowing, or disappearing intervertebral space and paravertebral abscess were 85.45%, 32.73%, 90.91%, and 36.36%, respectively. The ratios of detection of DTS of bone destruction, sequestration, narrowing, or disappearing intervertebral space and paravertebral abscess were 100%, 69.09%, 90.91%, and 63.64%, respectively. The ratios of detection
of DTS of bone destruction, sequestration, and paravertebral abscess were higher than DR, and the ratio of detection of narrowing or disappearing intervertebral space had no significant difference between DR and DTS (shown in Table 2). 4. Discussion Nowadays, DR is still the most common imaging examination for first diagnosis of spinal tuberculosis because it is simple and feasible and has a low cost. DR images can show complete pictures of the spine and lesions, narrowing intervertebral space, kyphosis and spinal stenosis, bone destruction, and sequestration. DTS is a threedimensional imaging technology. It allows an arbitrary number of infocus planes to be generated retrospectively from a sequence of projection radiographs, and specific planes may be then reconstructed by shifting and adding these projection radiographs [6]. So DTS may reduce the residual blur from out-of-plane structures and provide a better visualization. In the paper, we found that the image quality of DTS was higher than DR, and the detection rates of bone destruction, sequestration, and paravertebral abscess were also higher for DTS than for DR. DR images have a low-density resolution, and they are also affected by overlapping tissues and organs as two-dimensional images. Therefore, they are inadequate for showing small lesions and swelling of the soft tissue around Table 1 Image quality of DR and DTS
DTS image DR image
Excellent
Inadequate
Total
55 46
0 9
55 55
464
D. Jiao et al. / Clinical Imaging 40 (2016) 461–464
Table 2 Ratios of detection of bone destruction, sequestration, and narrowing or disappearing intervertebral space and paravertebral abscess of DR and DTS Bone destruction
DR DTS χ2 P
Sequestration
Paravertebral abscess
Narrowing or disappearing intervertebral space
Detected
Undetected
Detected
Undetected
Detected
Undetected
Detected
Undetected
47 55 6.605 0.010
8 0
18 38 13.132 0.000
37 17
20 35 8.182 0.004
35 20
50 50 0.000 1.000
5 5
the spine and the spinal canal involved in lesion. As a three-dimensional imaging technology, DTS overcomes the adverse effect of overlapping tissues and organs in a two-dimensional image. DTS images can clearly show the internal structure of complicated parts and the relationship between them and surrounding tissues, and small bone destruction and sequestrum are also shown with the submillimeter plane. According to our experience, the imaging time of both DTS and CT was about 10 s, and DR was about 2 s; the cost of CT was much higher than DTS and DR, and the cost of DTS was a little more than DR; the radiation dose of CT was about 11.95 msv, DTS was about 0.85 msv, and DR was about 0.5 msv. These data were actual and from our data. Compared with CT, DTS have lower cost and radiation dose. Compared with DR, the cost and radiation dose of DTS were a little higher, but the image quality and detection rates of lesions were better as mentioned earlier. The limitations of the research were that the imaging time, cost, and radiation dose of DR, DTS, and CT were obtained from our experience and were not compared with statistical methods. In conclusion, DTS had better image quality and higher ratios of detection of lesions compared with DR and lower cost and radiation dose
compared with CT, and DTS could be applied in diagnosis and follow-up of spinal tuberculosis and other spinal conditions such as infections and suspected tumors, serving as a supplementary examination of DR. Acknowledgments None. References [1] Rezai AR, Lee M, Cooper PR. Modern management of spinal tuberculosis. Neurosurgery 1995;36:87–97. [2] Boachi-Adjei O, Squillante RG. Tuberculosis of the spine. Orthop Clin North Am 1996; 27:95–103. [3] Oguz E, Sehirlioglu A, Altinmakas M, et al. A new classifiation and guide for surgical treatment of spinal tuberculosis. Int Orthop 2008;32:127–33. [4] Garg RK, Somvanshi DS. Spinal tuberculosis: a review. J Spinal Cord Med 2011;34:440–54. [5] Vikgren J, Zachrisson S, Svalkvist A, et al. Comparison of chest tomosynthesis and chest radiography for detection of pulmonary nodules: human observer study of clinical case. Radiology 2008;249:1034–41. [6] Dobbins JT, Godfrey DJ. Digital x-ray tomosynthesis: current state of the art and clinical potential. Phys Med Biol 2003;48:R65-106.
Contents lists available at ScienceDirect
Clinical Imaging journal homepage: http://www.clinicalimaging.org
Application of digital tomosynthesis in diagnosing spinal tuberculosis Dan Jiao, Dong-yan Yang ⁎, Wen Tian, Hui Wang, Hong-ping Ji Department of Ultrasound, China-Japan Union Hospital of Jilin University, No. 126, Xian-Tai Street, Changchun City, 130021, China
a r t i c l e
i n f o
Article history: Received 17 August 2015 Received in revised form 24 October 2015 Accepted 5 November 2015 Available online xxxx Keywords: Digital tomosynthesis Digital radiology Spinal tuberculosis Image quality Ratios of detection of lesions
a b s t r a c t Objective: To study the value of digital tomosynthesis (DTS) applied in diagnosing spinal tuberculosis. Methods: Images of digital radiology (DR) and DTS were retrospectively analyzed in patients with spinal tuberculosis, and image quality and ratio of detection of lesions were compared. Results: Excellent ratio was higher for DTS images than DR images; ratios of detection of bone destruction, sequestration, and paraspinal abscess were higher for DTS than DR. Conclusions: DTS had better image quality and ratios of detection of lesions and could be applied in diagnosing and following spinal tuberculosis and other spinal conditions such as infections or suspected tumors.
© 2016 Elsevier Inc. All rights reserved.
1. Introduction
2.2. Examination methods
Spinal tuberculosis is the most common in bone and joint tuberculosis [1–3], and it has very high prevalence and morbidity in China [4]. Tuberculosis is routinely diagnosed by digital radiology (DR) combined with tuberculin test, but digital tomosynthesis (DTS) is a new tool in the imaging diagnosis of tuberculosis. DTS has a lower radiation dose compared with Computed Tomography (CT) [5] and higher spatial resolution compared with DR. In the paper, the image quality and detection rates of bone destruction, sequestration, narrowing, or disappearing intervertebral space and paravertebral abscess between DR and DTS were compared, and the aim is to determine the value of DTS applied in diagnosing spinal tuberculosis.
DR was performed with Ysio (Siemens, Germany), and anterior– posterior view and lateral view were adopted. DTS was performed with Sonialvision Satire II (Shimadzu, Japan), using the procedure of TOMOS. The distance was 1100 mm between the X-ray tube and flat panel detector, and the exposure conditions were determined according to the thickness of different locations. The exposure conditions were 85 kV and 50 mAs for anterior–posterior view of the lumbar vertebrae, and 100 kV and 45 mAs for lateral view of the lumbar vertebrae. Postprocessing parameters included range of 100 mm and pitch of 2.0 mm. Seventy-four frames of DTS images were reconstructed, and sharp images were chosen.
2. Materials and methods
2.3. Reading images and evaluating image quality
2.1. Patients
Two radiologists, including a chief physician and an associate chief physician, simultaneously read the images of DR and DTS. Image quality was evaluated, and bone destruction, sequestration, narrowing, or disappearing intervertebral space and paravertebral abscess were detected. The two radiologists should be in agreement after discussion if they had different opinions. The criteria of an excellent image were as follows: (a) the image included the targeted vertebrae completely; (b) the spinal canal and superior and inferior articular process had clear structure and satisfactory contrast in lateral views; (c) the cortical bone had clear display. The criteria of an inadequate image were as follows: (a) the image did not include the targeted vertebrae completely, or its location was not standard, which led to bilateral shadow; or (b) the image deviated from center line and had inadequate exposure,
Fifty-five patients with spinal tuberculosis were enrolled in China– Japan Union Hospital of Jilin University from May 2011 to May 2015. Both DR and DTS were performed in all the patients before surgery, and tuberculosis was confirmed with surgical pathology. These patients included 23 males and 32 females and had a mean age of 40.1 years (6–62 years) and duration of 24.8 months (half a month–10 years). ⁎ Corresponding author. Department of Ultrasound, China-Japan Union Hospital of Jilin University, No. 126, Xian-Tai Street, Changchun City, 130021, China. Tel./fax: +86-4322615087. E-mail address: [email protected] (D. Yang). http://dx.doi.org/10.1016/j.clinimag.2015.11.003 0899-7071/© 2016 Elsevier Inc. All rights reserved.
462
D. Jiao et al. / Clinical Imaging 40 (2016) 461–464
A
B
C
D
Fig. 1. A 45-year-old woman with thoracic three to nine vertebral tuberculosis diagnosed with DTS. DR images: A.1 and A.2 showed (a) increased density in thoracic vertebral body 8 and 9; (b) bone destruction in vertebral body border, narrowing intervertebral space between thoracic vertebrae 8 and 9; and (c) fusiform broadening of the bilateral paravertebral lines. DTS images: A.3 and A.4 showed (a) bone destruction in the anterior border of thoracic vertebral body 3, left border of thoracic vertebral body 4 and 5, superior and inferior border of thoracic 7, 8, and 9; (b) narrowing intervertebral space between thoracic vertebrae 3 and 4, between 4 and 5, between 7 and 8, and between 8 and 9; and (c) fusiform broadening of the bilateral paravertebral lines.
which led to bad display of lesion. Osteoporosis was determined according to cortical thinning and increased radiolucency for DR images.
vertebral bodies were most frequently involved (40 patients). Total of vertebral bodies involved was 160.
2.4. Statistical analysis 3.2. Main DR manifestations of spinal tuberculosis The statistical analysis was performed with the Statistical Product and Service Solutions (SPSS) Version 19.0. The image quality and detection rates of bone destruction, sequestration, narrowing, or disappearing intervertebral space and paravertebral abscess between DR and DTS were compared with chi-square test. Significance was set at Pb 0.05. 3. Results 3.1. Vertebral body involved in lesion The vertebral body involved in lesion included the cervical vertebrae (3 patients), thoracic vertebrae (10 patients), vertebrae of thoracolumbar segment (10 patients), lumbar vertebrae (20 patients), and lumbosacral vertebrae (12 patients). A single vertebral body was involved in three patients, and multiple vertebral bodies were involved in 52 patients. Six vertebral bodies were involved at most (one patient), and two to three
A
B
Bone destruction was detected in 47 patients, and DR images showed (a) osteoporosis and (b) circular, irregular, and vesicant defect. Sequestration was detected in 18 patients, and DR images showed dense shadow with the size of grit or rice in the region of bone destruction. Narrowing or disappearing intervertebral space was detected in 50 patients, and 20 patients among them had mutual embedding vertebral bodies with angular deformity whose borders were coarse and blurred, and meanwhile had changed curvature of the spinal column. Paravertebral abscess was detected in 20 patients, and mottling calcification shadow was detected in five patients among them. DR images of paravertebral abscess showed posterior wall of pharynx abscess for tuberculous cervical spondylitis, fusiform broadening of the paravertebral line for tuberculosis of thoracic spine (shown in Fig. 1), and blur, satiation, and broadening of the psoas major muscle for tuberculosis of lumbar spine.
C
D
Fig. 2. A 26-year-old woman with lumbar three to five vertebral tuberculosis diagnosed with DTS. DR images: B.1 and B.2 showed (a) irregular bone destruction in lumbar vertebral body 3 and 4; (b) collapse and density of lumbar vertebral body 4; and (c) narrowing and disappearing intervertebral space between lumbar vertebrae 3 and 4. DTS images: B.3 and B.4 showed (a) bone destruction in lumbar vertebral body 3 and 4; (b) inhomogeneous reduced density in lumbar vertebral body 5 with multiple destruction regions inside the vertebral body and small patchy sequestrum shadow surrounding the vertebral body; and (c) abscess formation in the bilateral psoas major muscles.
D. Jiao et al. / Clinical Imaging 40 (2016) 461–464
463
A
B
C
D
E
F
Fig. 3. A 47-year-old woman with lumbar 2–sacral 1 vertebral tuberculosis diagnosed with DTS and CT. DR images: C.1 and C.2 showed (a) posterior deformity of the lumbosacral vertebrae; (b) irregular bone destruction in lumbar 3–sacral 1 vertebral body which had no normal morphous and had multiple small sequestrum shadows in localized region; and (c) abscess formation and mottling calcification shadow in the right psoas major muscle. DTS images: C3 and C4 showed (a) bone destruction in lumbar 3–sacral 1 vertebral body; (b) the spinal canal was involved in lesion; and (c) semicircular bone destruction with mild sclerosis in its border in the posterior border of lumbar vertebral body 2. CT images: C5 and C6 confirmed the diagnosis of DTS.
3.3. Main DTS manifestations of spinal tuberculosis Bone destruction was detected in 55 patients. DTS images showed irregular vertebral body, moth-eaten destruction, cavernose destruction, localized osteolytic change, and fragmented change, and most patients had multiple manifestations. Wedging vertebral body was detected in 35 patients (shown in Fig. 2). Patchy or gritty sequestration was detected in 38 patients, and DTS images showed irregular hyperdense shadow. Narrowing or disappearing intervertebral space was detected in 50 patients, and 20 patients among them had mutual embedding vertebral bodies with angular deformity whose borders were coarse and blurred, and meanwhile had changed curvature of the spinal column (shown in Fig. 3). Paravertebral abscess was detected in 35 patients, and gritty and mottling calcification shadow was detected in 8 patients among them (shown in Fig. 3). 3.4. Image quality of DR and DTS The excellent ratio was 83.64% for DR images and 100% for DTS images. The excellent ratio was higher for DTS images than for DR images (χ2=7.745, P=0.005) (Table 1). 3.5. Ratios of detection of bone destruction, sequestration, narrowing, or disappearing intervertebral space and paravertebral abscess of DR and DTS The ratios of detection of DR of bone destruction, sequestration, narrowing, or disappearing intervertebral space and paravertebral abscess were 85.45%, 32.73%, 90.91%, and 36.36%, respectively. The ratios of detection of DTS of bone destruction, sequestration, narrowing, or disappearing intervertebral space and paravertebral abscess were 100%, 69.09%, 90.91%, and 63.64%, respectively. The ratios of detection
of DTS of bone destruction, sequestration, and paravertebral abscess were higher than DR, and the ratio of detection of narrowing or disappearing intervertebral space had no significant difference between DR and DTS (shown in Table 2). 4. Discussion Nowadays, DR is still the most common imaging examination for first diagnosis of spinal tuberculosis because it is simple and feasible and has a low cost. DR images can show complete pictures of the spine and lesions, narrowing intervertebral space, kyphosis and spinal stenosis, bone destruction, and sequestration. DTS is a threedimensional imaging technology. It allows an arbitrary number of infocus planes to be generated retrospectively from a sequence of projection radiographs, and specific planes may be then reconstructed by shifting and adding these projection radiographs [6]. So DTS may reduce the residual blur from out-of-plane structures and provide a better visualization. In the paper, we found that the image quality of DTS was higher than DR, and the detection rates of bone destruction, sequestration, and paravertebral abscess were also higher for DTS than for DR. DR images have a low-density resolution, and they are also affected by overlapping tissues and organs as two-dimensional images. Therefore, they are inadequate for showing small lesions and swelling of the soft tissue around Table 1 Image quality of DR and DTS
DTS image DR image
Excellent
Inadequate
Total
55 46
0 9
55 55
464
D. Jiao et al. / Clinical Imaging 40 (2016) 461–464
Table 2 Ratios of detection of bone destruction, sequestration, and narrowing or disappearing intervertebral space and paravertebral abscess of DR and DTS Bone destruction
DR DTS χ2 P
Sequestration
Paravertebral abscess
Narrowing or disappearing intervertebral space
Detected
Undetected
Detected
Undetected
Detected
Undetected
Detected
Undetected
47 55 6.605 0.010
8 0
18 38 13.132 0.000
37 17
20 35 8.182 0.004
35 20
50 50 0.000 1.000
5 5
the spine and the spinal canal involved in lesion. As a three-dimensional imaging technology, DTS overcomes the adverse effect of overlapping tissues and organs in a two-dimensional image. DTS images can clearly show the internal structure of complicated parts and the relationship between them and surrounding tissues, and small bone destruction and sequestrum are also shown with the submillimeter plane. According to our experience, the imaging time of both DTS and CT was about 10 s, and DR was about 2 s; the cost of CT was much higher than DTS and DR, and the cost of DTS was a little more than DR; the radiation dose of CT was about 11.95 msv, DTS was about 0.85 msv, and DR was about 0.5 msv. These data were actual and from our data. Compared with CT, DTS have lower cost and radiation dose. Compared with DR, the cost and radiation dose of DTS were a little higher, but the image quality and detection rates of lesions were better as mentioned earlier. The limitations of the research were that the imaging time, cost, and radiation dose of DR, DTS, and CT were obtained from our experience and were not compared with statistical methods. In conclusion, DTS had better image quality and higher ratios of detection of lesions compared with DR and lower cost and radiation dose
compared with CT, and DTS could be applied in diagnosis and follow-up of spinal tuberculosis and other spinal conditions such as infections and suspected tumors, serving as a supplementary examination of DR. Acknowledgments None. References [1] Rezai AR, Lee M, Cooper PR. Modern management of spinal tuberculosis. Neurosurgery 1995;36:87–97. [2] Boachi-Adjei O, Squillante RG. Tuberculosis of the spine. Orthop Clin North Am 1996; 27:95–103. [3] Oguz E, Sehirlioglu A, Altinmakas M, et al. A new classifiation and guide for surgical treatment of spinal tuberculosis. Int Orthop 2008;32:127–33. [4] Garg RK, Somvanshi DS. Spinal tuberculosis: a review. J Spinal Cord Med 2011;34:440–54. [5] Vikgren J, Zachrisson S, Svalkvist A, et al. Comparison of chest tomosynthesis and chest radiography for detection of pulmonary nodules: human observer study of clinical case. Radiology 2008;249:1034–41. [6] Dobbins JT, Godfrey DJ. Digital x-ray tomosynthesis: current state of the art and clinical potential. Phys Med Biol 2003;48:R65-106.