MINISTRY OF EDUCATION AND TRAINING MINISTRY OF DEFENSE INSTITUTE OF CLINICAL MEDICAL SCIENCE 108 TONG THI THU HANG RESEARCH ON IMAGING CHARACTERISTICS AND VALUE OF COMPUTED TOMOGRAPHY MYELOGRAPHY IN T[.]
MINISTRY OF EDUCATION AND TRAINING MINISTRY OF DEFENSE INSTITUTE OF CLINICAL MEDICAL SCIENCE 108 TONG THI THU HANG RESEARCH ON IMAGING CHARACTERISTICS AND VALUE OF COMPUTED TOMOGRAPHY MYELOGRAPHY IN THE DIAGNOSIS OF TRAUMATIC BRACHIAL PLEXUS INJURY Specialisation: Image Diagnostics Code: 62720166 SUMMARY OF DOCTORAL THESIS HANOI – 2022 Thesis completed at: INSTITUTE OF CLINICAL MEDICAL SCIENCE 108 Supervisors: Lam Khanh, Associate Professor, Doctor Le Van Doan, Associate Professor, Doctor Reviewer 1: Reviewer 2: Reviewer 3: The Thesis will be definded to Thesis grading committee at the Institute level Organized at Institute of Clinical Medical Science 108 Time: Date: The Thesis can be found at: Vietnam National Library Institute of Clinical Medical Science 108 Library INTRODUCTION Brachial plexus injury is commonly caused by trauma, mainly traffic accidents, leading to paralysis, and total or partial loss of sensation in the upper extremities Imaging methods include X-ray, ultrasound, computed tomography (CT) myelography and magnetic resonance imaging (MRI) Which, CT myelography and MRI is commonly used because CT myelography has a high value in diagnosing root avulsion which is the most common type and MRI can diagnose all types of branchial plexus lesions MRI has many advantages, however, it cannot be performed in patients with fixation hardware and difficult to diagnose incomplete root avulsion CT myelography overcomes the above disadvantages At the Military Central Hospital 108, CT myelography and MRI for diagnosing branchial plexus lesions are applied Up to now, there has been no study on the value of CT myelography That's why we conduct the study “research on imaging characteristics and value of computed tomography in the diagnosis of traumatic brachial plexus injury” with objects: Imaging characteristics of CT myelography in the diagnosis of traumatic brachial plexus avulsion Value of CT myelography in the diagnosis of traumatic brachial plexus avulsion Dissertation novelty: The study is the first one in Vietnam to apply CT myelography in the evaluation of traumatic brachial plexus injury Contribution to Image Diagnostics: A new diagnostic technique is developed Contribution to Treatment: The study assesses systematic brachial plexus injury and simultaneously indicates the correlation between clinic and image diagnostics, thus assisting clinical practitioners in the determination of an appropriate treatment policy to recover effectively the patients’ functions Thesis structure The dissertation consists of 126 pages: Question pages, overview 38 pages; Subject and methodology 18 pages; Results 27 pages; Comment 38 pages; Conclusion pages; Limitation: 1; The thesis consists of 26 tables, 20 graphs, and 111 references Chapter OVERVIEW 1.1 Role of CT myelography in the diagnosis of traumatic brachial plexus avulsion CT myelography is a method of taking cervical spinal cord CT with contrast injection into the spinal canal, based on the principle that the contrast agent in the spinal canal increases contrast with the nerve roots less dense, from which to diagnose root avulsion This method was first applied in 1986 by Marshall and De Silva, but the accurate diagnosis rate is not different from the X-ray myelography The development of generations of multi-sequential CT scanners and software for image reconstruction and image noise reduction were helping cervical CT myelography and have made it highly valuable in diagnosing traumatic nerve root avulsion, especially being superior compared with MRI in incomplete root avulsion Classification of root avulsion on CT myelography based on the classification of Nagano (1989) includes N: Normal roots; A1: Minor abnormality in the sleeve or root exit site; A2: Sleeve amputation, root deformity; A3: Sleeve amputation and no roots or rootlets observed; D: Missing the sleeve of the root; M: Pseudomeningocele 1.2 The application of CT myelography in the diagnosis of traumatic brachial plexus lesions in the world and Vietnam In the world, since the advent of CT myelography, there have been studies comparing the value of this method with standard X-ray myelography, concluding that the method is not superior to standard X-ray myelography in diagnosing root avulsion lesions Further studies on the generations of multi- rows CT combined with multiplane images, the research directions focus on comparing the value of CT myelography with standard X-ray myelography and MRI Several studies compare the diagnostic value of CT myelography on different planes Conclusions mostly confirm the value of the method in diagnosing root avulsion lesions as superior to other methods, especially in incomplete root avulsion with high sensitivity, specificity and accuracy rate In Vietnam, CT myelography has been performed only at 108 Military Central Hospital since 2015 in the diagnosis of a traumatic root avulsion 108 Central Military Hospital is a surgical facility for microsurgery for nerve grafting to treat traumatic nerve lesions, the need for diagnosis and treatment for patients with branchial plexus lesions is high, especially for those who can’t perform MRI or patients who have performed MRI but the results are not clinically relevant, it is necessary to conduct a cervical CT myelography to diagnose root avulsion lesions So far, we have had several reports on the value of this method in domestic journals Chapter OBJECTIVES AND METHODS 2.1 Research subjects and methods The study was conducted on 179 patients who have scanned CT myelography at the Department of Radiology and undergoing surgery at the Institute of Trauma and Orthopedics of 108 Military Central Hospital from May 2015 to May 2020 2.1.1 Standard selection - Patients with a history of trauma, were clinically diagnosed with brachial plexus lesion, suspected of having root avulsion lesion, underwent CT myelography and underwent surgery at the Institute of Trauma and Orthopedics, 108 Central Military Hospital - There are medical records, CT scans, surgical reports on the postoperative diagnosis of brachial plexus lesions, surgical method with nerve transfer to restore brachial plexus, and detailed descriptions of brachial plexus lesions according to the research patient record 2.1.2 Exclusion criteria - Patients having traumatic brain injury or traumatic spinal cord injury associated with traumatic brachial plexus injury lead to falsification of the clinical signs of brachial plexus lesions - Cases of brachial plexus injury due to obstetric trauma in neonates - Patients who have not full medical records or lose images, and research materials 2.1.3 Sample size Convenient sample size, taking all patients who meet the selection criteria for the study (not less than 100 patients) The study was conducted on 179 patients 2.1.4 Place of Research Department of radiology and surgery of upper extremities, 108 Military Central hospital 2.2 Research Methods 2.2.1 Research design: A prospective, cross-sectional descriptive study 2.2.2 Research facilities - Brivo 16 rows CT Scan (GE- United States) at the department of radiology, 108 Military hospital - Contrast agent Omnipaque 300 mg/ml - Sterile instrument tray and 22G lumbar puncture needle - Plexygon nerve stimulator (Vygon-Italy) 2.2.3 CT myelography procedure The patient was fully explained about the imaging procedure, taking a full medical history, allergies, assessing the spinal status and lumbar puncture site, excluding contraindications (cerebrospinal infections, increased intracranial pressure) The imaging procedure includes steps: lumbar puncture, injection of Omnipaque contrast agent 300 mg/ml into the spinal canal, computed tomography scan through the cervical spinal cord, and imaging reconstruction of the brachial plexus roots 2.2.3 Research contents 2.2.3.1 General characteristics of branchial plexus lesion: Ages, sex, cause of trauma, side of trauma, combined trauma, time from injury to the taking CT myelography and undergoing surgery 2.2.3.2 Characteristics of brachial plexus lesions on CT myelography: - Description of lesion characteristics according to author Nagano (1989) and Carvalho (1997) include: + Abnormal root exit: Normally, the anterior and posterior roots are continuous with the spinal cord and emerge from the spinal canal as soft as a sleeve Root exit abnormality is when an amputated or missing root exit is observed, while the anterior and posterior roots are normal + Anterior root lesion: No image of anterior roots or a decrease in the number of rootlets of anterior roots compared with the opposite side + Posterior root lesion: No image of posterior roots or reduced number of rootlets of posterior roots compared with the opposite side + Pseudomeningocele: The image of the herniated sac of cerebrospinal fluid that is usually accompanied by complete root avulsion, that is, the rootlets are not observed, however, there is also a small percentage of associated pseudomeningocele with incomplete root avulsion, that is, the rootlets are still partially observed + Cerebrospinal fluid column defect: This sign is caused by the roots being avulsed and the spinal cord being pulled, causing the cerebrospinal fluid column defect at the location of the damaged root - Location of root lesions: C5, C6, C7, C8, T1 - Correlation of damaged root location: C5 and C6, C5- C6 and C7, C8 and T1, C8- T1 and C7 - Describe the number of damaged roots: 0- roots - Classification of lesions avulsion by Nagano classification (1989): N (normal), A1 (incomplete root avulsion), A2 (incomplete root avulsion), A3 (complete root avulsion), D (complete root avulsion), M (complete root avulsion) 2.2.3.3 Characteristics of lesions in surgery: Describe the types of lesions in surgery including root avulsion and other lesions (root fracture, root atrophy, edema of root, trunks, divisions and cords) 2.2.3.4 Compare CT myelography with surgery: Compare and calculate the diagnostic relevance of root avulsion on CT myelography and surgery at each root position, the upper root group (C5, C6 ± C7) and the lower root group (C8, T1 ± C7) 2.2.4 Image and data processing - CT images of patients are stored as DICOM 3.0 and PNG - CT myelography is diagnosed by the PhD student (under the supervision of the instructor) and saved as a Word file Statistics are stored in the computer in the form of Excel tables and then processed using SPSS 20.0 software - Algorithms used in the study: Descriptive statistics of the signs of rooting C5-T1 by absolute number and percentage, location, quantity, and extent of lesions at each C5-T1 root position The relationship between the location of the damaged roots and the signs of lesions Comparison of diagnostic results of root avulsion between CT myelography and surgery Calculation of the K value of CT myelography in the diagnosis of root avulsion lesions compared with surgery Study map Chapter RESEARCH RESULTS 3.1 General characteristics of patients with brachial plexus injuries - Brachial plexus injuries occur mostly in young men: The median value was 28 (50% of patients had age ≤ 28, male/female = 15.3) - The main cause of brachial plexus injuries is traffic accidents, accounting for 98.3% left > right Most of them have combined trauma (52.0%) Most patients underwent CT scans within ≤ 90 days after injury, and the majority of patients underwent surgery within ≤ 120 days (4 months) after injury 11 Table 3.6 The number of imaging sigs on each root site C5 C6 C7 C8 T1 Root n % n % n % n % n % Lesion Normal 57 31,8 31 17,3 50 27,9 81 45,3 112 62,6 36 20,1 24 13,4 11 6,2 2,8 0,6 sign 69 38,6 87 48,6 55 30,7 22 12,3 16 8,9 signs 18 10,1 37 20,7 63 35,2 69 38,6 51 28,5 signs Comments: Each root site has or signs more than only sign, there were no and signs of root lesions witnessed on CT myelography Table 3.7 The imaging signs mostly combined Locations C5 C6 C7 C8 T1 Signs Number Total Ventral- dorsal root lesion Ventral- dorsal root lesionroot exit abnormalities Ventral- dorsal root lesionpseudomeningocele Ventral- dorsal root lesion Ventral- dorsal root lesionpseudomeningocele Ventral- dorsal root lesion Ventral- dorsal root lesionpseudomeningocele Ventral- dorsal root lesion Ventral- dorsal root lesionpseudomeningocele Ventral- dorsal root lesion 67 69 Percentage (%) 97,1 18 44,4 18 44,4 83 87 95,4 26 37 70,3 52 55 94,5 53 63 84,1 22 22 100,0 60 69 87,0 12 16 75,0 46 51 90,2 Ventral- dorsal root lesionpseudomeningocele 12 Comments: Signs of ventral - dorsal root lesion and ventraldorsal root lesion- psedomeningocele holds a tremendously higher percentage at all locations of root avulsion Table 3.8 Classification of root avulsion by Nagano (1989) (n=179) C5 C6 C7 C8 T1 Root Lesion n % n % n % n % n % Normal 57 31,8 31 17,3 50 28,0 82 45,8 112 62,6 12 6,7 3,4 1,7 0,6 0,0 A1 41 22,9 32 17,9 14 7,8 2,8 0,0 A2 60 33,5 82 45,8 52 29,2 23 12,9 17 9,5 A3 3,9 24 13,4 51 28,7 59 33 46 25,7 M 1,1 2,2 4,5 5,0 2,8 D Comments: Classification of A3 lesions (complete avulsion) hold a tremendously higher percentage at all location of root avulsion from C5 to T1, secondly, this is classification of A2 lesions (incomplete avulsion) and M lesions (root avulsion with pseudomeningocele) 3.3 Value of CT myelography in diagnostic of brachial plexus injuries compare with surgery 3.3.1 Root lesion of brachial plexus following surgery result Figure 13 Location of the root lesion on surgery 13 Comments: Lesions of high-level root (C5,6,7) hold higher percentage than low level root (C8, T1), C5 root lesion combined with C5 root lesion hold highest percentage (87,7%) Figure 3.14 Number of root lesions Comments: - The lesions tend to occur with more than roots, lesion of roots (complete lesion of roots) hold the highest percentage (40,2%) - The lesion of only root occurred patients (2 patients occur at C5 site and patient occurred at C7 site) hold 1,7 % - There is no root lesion occurring in patients (4,5 %) Table 3.12 Level of root lesion following surgery result Level Normal Avulsion Rupture Edema Atrophy Root n % n % n % n % n % C5 17 9,5 132 73,7 25 14,0 12 6,7 21 11,7 C6 17 9,5 150 83,8 3,9 4,5 23 12,9 C7 50 27,9 124 69,3 2,2 1,1 20 11,7 C8 83 46,4 90 50,3 1,7 1,7 14 7,8 T1 100 56,2 71 40,0 2,3 1,7 5,1 14 Comments: - The main lesions according to surgery results are root avulsion, accounting for the majority at positions C5, C6, C7, C8 sites, of which the highest rate is at C6 roots, accounting for 83.8% - There is no root lesion that occurred highest at T1 site accounting for 56,2% % 90 86,6 80 70 64,8 60 50 47,5 40,8 40,2 37,4 40 30 20 10 Figure 3.15 Lesion of roots according to surgery results Comments: Lesions of high roots were mostly, in which lesions of C5 and C6 sites accounted for the highest percentage (86,6%) 3.2.2 Value of CT myelography in diagnosis of traumatic brachial plexus injuries compare with surgery 15 Table 3.17 Value of CT myelography in diagnosis of root avulsion at each site from C5 to T1 CT Root site Number Number 122 132 57 47 148 150 31 29 128 124 51 55 97 90 82 89 Lesion 68 71 without 111 107 Lesion C5 without lesion Lesion C6 without lesion Lesion C7 without lesion Lesion C8 without lesion T1 myelography Surgery Value of CT myelography Agreement (%) Kappa 89,9 0,76 93,3 0,76 92,2 0,81 90,5 0,81 96,1 0,91 lesion Comments: CT myelography had value in diagnosis of root avulsion with high agreement at all of root site C5, C6 and very high agreement at all of root site C7, C8 and T1 compare with surgery 16 Table 3.18 Value of CT myelography in diagnosis of high root avulsion (C5,6 ± C7) CT Root site Lesion C5-C6 without lesion C5-C6C7 Lesion without lesion myelography Surgery Number Number 118 129 61 50 88 94 91 85 Diagnosis value of CT myelography Agreement Kappa (%) 86,0 0,68 84,4 0,69 Comments: CT myelography has high agreement compared with surgery in diagnosis of high root avulsion of brachial plexus Tabe 3.19 Value of CT myelography in diagnosis of high root avulsion (C8, T1 ± C7) CT myelography Surgery Diagnosis value of CT myelography Root site Number Lesion C8-T1 without lesion C7C8-T1 Lesion without lesion Number Agreement (%) Kappa 68 71 111 108 64 69 115 110 96,1 0,92 95,0% 0,89 17 Comments: CT myelography have very high agreement compare with surgery in diagnosis of low root avulsion of branchial plexus Table 3.20 Value of CT myelography in diagnosis of total root avulsion CT Diagnosis value of CT Surgery myelography myelography Root site Agreement Number Number Kappa (%) Lesion 38 48 91,1 0,76 C5-T1 without 141 131 lesion Comments: CT myelography have high agreement compare with surgery in diagnosis of total root avulsion of brachial plexus Chapter DICUSSION 4.1 General characteristics of patients Age is not evenly distributed, mainly in the young age group, 50% of the study participants are ≤ 28 years old, the majority of which are male (93.9%) The results are similar to other studies, and the brachial plexus injuries are mainly seen in young men, people of working age The leading cause is traffic accidents, accounting for 98.3% (100% is motorcycle accidents), consistent with other studies that also concluded that traffic accidents and occupational accidents mainly cause brachial plexus injuries The combined injuries account for a high rate (52.0%), of which the most common is the fracture of the ipsilateral limb with a rate of ossification of 62.8% Other authors also had a high percentage of combined lesions, but lower than our 18 study Because the group of patients in the study were mainly those with ossification and can’t conduct MRI, it is necessary to perform contrast-enhanced CT of the cervical spinal cord to diagnose root canal lesions The time from injury to CT scan accounted for the highest rate in about ≤ months, to surgery accounted for the highest rate in about ≤ months Other studies have differing opinions, but the earliest recommended interval of weeks from injury to CT scan to avoid fake images of blood clots, time from injury to surgery ≤ months brings the best neurological recovery results 4.2 Characteristics imaging of CT myelography 4.2.1 Location of roots lesion Upper root lesions predominate, the highest at the level of C6 (82.7%), gradually decreasing at the rates of C7 (72%), C5 (68.2%), C8 (54) 8%) and T1(37.4%) Our results are consistent with other authors The reason is that the upper roots have less soft and muscular cover than the lower roots, on the other hand, the direction of the upper roots is from top to bottom, which is more susceptible to the impact of trauma than the direction of the lower roots is the direction horizontal from the inside out 4.2.2 Number of roots lesion Lesions tend to occur in multiple roots In which, C5 root damage is often accompanied by C6 root, C5 and C6 root damage is often accompanied by C7 root injury C8 root damage is often associated with T1 root damage and C8, T1 root damage is often associated with C7 root damage with a statistically significant difference (p