Objective To summarize the methods and applications for quantitative measurement of iron in human.Methods The methods and applications for quantitative measurement of iron in human were analyzed retrospectively via reviewing the literatures domesticly and abroad， and summarized the advantages and disadvantages respectively. Results The methods for quantitative measurement of iron included laboratory tests， pathology examinations， CT， superconducting quantum interference device investigation （SQUID）， and MRI. Conclusions Laboratory test is the most simple and economic method for quantitative measurement of iron in human. Percutaneous liver biopsy is the gold standardmethod. Radiologic examinations， especially MRI， may be main methods of measuring liver iron content in future.
Objective To summarize the advances in MRI-based bone quality scoring systems and their clinical applications. Methods A comprehensive literature review was conducted on recent studies related to the MRI-based bone quality scoring system, focusing on measurement methods, influencing factors, and clinical significance. Results Osteoporosis has a high incidence in China, significantly impacting patients’ quality of life and the postoperative outcomes of related orthopedic surgeries. Early identification of osteoporosis holds important clinical significance. In recent years, both domestic and international research has enriched the MRI-based bone quality scoring systems, which includes vertebral bone quality scoring, endplate bone quality scoring, and pedicle bone quality scoring. Compared to the “gold standard” of bone density measurement, dual-energy X-ray absorptiometry, the bone quality scoring systems demonstrate good efficacy in identifying abnormal bone mass and predicting postoperative complications, while being less influenced by degenerative changes in the lumbar spine, indicating its important clinical application value. ConclusionThe MRI-based bone quality scoring systems have good value in clinical applications. However, current studies are mostly retrospective cohort and case-control studies, which carry a risk of bias. The clinical application value needs further clarification through meta-analysis and large-scale prospective studies.
ObjectiveTo summarize the relationship between lateral femoral notch sign (LFNS) and anterior cruciate ligament (ACL) rupture. MethodsThe relevant literature of LFNS at home and abroad in recent years was retrospectively reviewed, and its mechanism, diagnostic criteria and influencing factors in diagnosis of ACL rupture were summarized and analyzed.ResultsThe LFNS is associated with rotational stability of the knee. As an indirect sign of ACL rupture, the LFNS has high clinical diagnostic value, especially the diagnosis of ACL rupture with lateral meniscus injury.ConclusionThe diagnostic criteria and influencing factors of LFNS in diagnosis of ACL rupture are still unclear and controversial, which needs further study.
ObjectiveTo study the anatomical characteristics of blood vessels in the lateral segment of the vertebral body through the surgical approach of oblique lumbar interbody fusion (OLIF) using MRI imaging, and evaluate its potential vascular safety zone. Methods The lumbar MRI data of 107 patients with low back and leg pain who met the selection criteria between October 2019 and November 2022 were retrospectively analyzed. The vascular emanation angles, vascular travel angles, and the length of vessels in the lateral segments of the left vertebral body of L1-L5, as well as the distance between the segmental vessels in different Moro junctions of the vertebral body and their distances from the edges of the vertebrae in the same sequence (bottom marked as I, top as S) were measured. The gap between the large abdominal vessels and the lateral vessels of the vertebral body was set as the lateral vascular safe zones of the lumbar spine, and the extent of the safe zones (namely the area between the vessels) was measured. The anterior 1/3 of the lumbar intervertebral disc was taken as the simulated puncture center, and the area with a diameter of 22 mm around it as the simulated channel area. The proportion of vessels in the channel was further counted. In addition, the proportions of segmental vessels at L5 without a clear travel and with an emanation angel less than 90° were calculated. Results Except for the differences in the vascular emanation angles between L4 and L5, the vascular travel angles between L1, L2 and L4, L5, and the length of vessels in the lateral segments of the vertebral body among L1-L4 were not significant (P>0.05), the differences in the vascular emanation angles, vascular travel angles, and the length of vessels between the rest segments were all significant (P<0.05). There was no significant difference in the distance between vessels of L1, L2 and L2, L3 at Moro Ⅰ-Ⅳ junctions (P>0.05), in L3, L4 and L4, L5 at Ⅱ and Ⅲ junction (P>0.05). There was no significant difference in the vascular distance of L2, L3 between Ⅱ, Ⅲ junction and Ⅲ, Ⅳ junction, and the vascular distance of L3, L4 between Ⅰ, Ⅱ junction and Ⅲ, Ⅳ junction (P>0.05). The vascular distance of the other adjacent vertebral bodies was significant different between different Moro junctions (P<0.05). Except that there was no significant difference in the distance between L2I and L3S at Ⅰ, Ⅱ junction, L3I and L4S at Ⅱ, Ⅲ junction, and L2I and L3S at Ⅲ, Ⅳ junction (P>0.05), there was significant difference of the vascular distance between the bottom of one segment and the top of the next in the other segments (P<0.05). Comparison between junctions: Except for the L3S between Ⅰ, Ⅱ junction and Ⅱ, Ⅲ junction, and L5S between Ⅰ, Ⅱ junction and Ⅱ, Ⅲ and Ⅲ, Ⅳ junctions had no significant difference (P>0.05), there were significant differences in the distance between the other segmental vessels and the vertebral edge of the same sequence in different Moro junctions (P<0.05). The overall proportion of vessels in the simulated channels was 40.19% (43/107), and the proportion of vessels in L1 (41.12%, 44/107) and L5 (18.69%, 20/107) was higher than that in the other segments. The proportion of vessels in the channel of Moro zone Ⅰ (46.73%, 50/107) and zone Ⅱ (32.71%, 35/107) was higher than that in the zone Ⅲ, while no segmental vessels in L1 and L2 were found in the channel of zone Ⅲ (χ2=74.950, P<0.001). Moreover, 26.17% (28/107) of the segmental vessels of lateral L5 showed no movement, and 27.10% (29/107) vascular emanation angles of lateral L5 were less than 90°. Conclusion L1 and L5 segmental vessels are most likely to be injured in Moro zones Ⅰ and Ⅱ, and the placement of OLIF channels in L4, 5 at Ⅲ, Ⅳ junction should be avoided. It is usually safe to place fixation pins at the vertebral body edge on the cephalic side of the intervertebral space, but it is safer to place them on the caudal side in L1, 2 (Ⅰ, Ⅱ junction), L3, 4 (Ⅲ, Ⅳ junction), and L4, 5 (Ⅱ, Ⅲ, Ⅳ junctions).
Objective To investigate whether preoperative T1 slope (T1S) in MRI can predict the changes of cervical curvature after expansive open-door laminoplasty (EOLP) in patients with cervical spondylotic myelopathy, so as to make up for the shortcomings of difficult measurement in X-ray film. Methods The clinical data of 36 patients with cervical spondylotic myelopathy who underwent EOLP were retrospectively analysed. There were 21 males and 15 females with an average age of 55.8 years (range, 37-73 years) and an average follow-up time of 14.3 months (range, 12-24 months). The preoperative X-ray films at dynamic position, CT, and MRI of cervical spine before operation, and the anteroposterior and lateral X-ray films at last follow-up were taken out to measure the following sagittal parameters. The parameters included C2-C7 Cobb angle and C2-C7 sagittal vertical axis (C2-C7 SVA) in all patients before operation and at last follow-up; preoperative T1S were measured in MRI, and the patients were divided into larger T1S group (T1S>19°, group A) and small T1S group (T1S≤19°, group B) according to the median of T1S, and the preoperative T1S, C2-C7 Cobb angle, C2-C7 SVA, and the C2-C7 Cobb angle and C2-C7 SVA at last follow-up, difference in axial distance (the difference of C2-C7 SVA before and after operation), postoperative curvature loss (the difference of C2-C7 Cobb angle before and after operation), the number of patients whose curvature loss was more than 5° after operation, and the number of patients whose kyphosis changed (C2-C7 Cobb angle was less than 0° after operation). Results The C2-C7 Cobb angle at last follow-up was significantly decreased when compared with preoperative value (t=8.000, P=0.000), but there was no significant difference in C2-C7 SVA between pre- and post-operation (t=–1.842, P=0.074). The preoperative T1S was (19.69±3.39)°; there were 17 cases in group A and 19 cases in group B with no significant difference in gender and age between 2 groups (P>0.05). The preoperative C2-C7 Cobb angle in group B was significantly lower than that in group A (t=–2.150, P=0.039), while there was no significant difference in preoperative C2-C7 SVA between 2 groups (t=0.206, P=0.838). At last follow-up, except for the curvature loss after operation in group B was significantly lower than that in group A (t=–2.723, P=0.010), there was no significant difference in the other indicators between 2 groups (P>0.05). Conclusion Preoperative larger T1S (T1S>19°) in MRI had a larger preoperative lordosis angle, but more postoperative physiological curvature was lost; preoperative T1S in MRI can not predict postoperative curvature loss, but preoperative larger T1S may be more prone to kyphosis.
Objective To evaluate the sensitivity and accuracy of SPIO-enhanced MR Imaging in the detection of focal hepatic lesions. Methods We searched MEDLINE (1966 to 2004), EMBSAE (1984 to 2004), The Cochrane Library (Issue 1, 2004), CBMdisc (Jan.1978 to Jul. 2004), CMCC (1994 to 2004), “Radiology”, “AJR” and “European Radiology” database. Data from pharmaceutical companies and our research were also added. Related journals published from 1985 to 2003 were handsearched. Participants were clinically suspected of focal hepatic lesions. The quality of studies was assessed, and descriptive systematic review was applied to evaluate the detection sensitivity and accuracy of the imaging modality. Results Ten studies (418 patients with 1 037 focal hepatic lesions) were included. Because the data of sensitivity and specificity could not be extracted from any of the 10 included studies, it was impossible to do the meta-analysis using SROC curve. The sensitivity of SPIO-enhanced MRI ranged from 66% to 100%; accuracy ranged from 76% to 97%. Conclusions At present, there is no evidence to ascertain that SPIO-enhanced MRI has a considerably high accuracy in the detection of focal hepatic lesions. More studies with good methodology are needed.
Objective Gunshot wound spreads to the surrounding tissues and organs, it is difficult to debride and easy to infect. The conventional treatment is thorough, extensive debridement, fully open drainage, which often causes normal tissue damage and compl ications. To evaluate the effectiveness of vacuum seal ing drainage (VSD) treating thepenetrating wound in porcine extremity by MRI and pathological methods so as to provide theoretical basis for future cl inical use. Methods Eight healthy adult pigs, weighing (45 ± 5) kg, were selected. Eight pairs of hind l imb penetrating wounds (16 wounds) were made by using Chinese-made 95-type rifle at 25 meters distance, which were randomly divided into experimental group (left side, n=8) and the control group (right side, n=8). After debriding and disinfecting the penetrating wounds at 6 hours after injury, wounds were treated with VSD in experimental group. The ball istics exports of the wounds were covered with single-layer gauze and imports were directly sutured and covered with sterile gauze in control group. The trajectory and the general condition of the adjacent skin were observed. MRI and histological observation were taken at 5, 24, 48, and 72 hours after injury, bacterial counting analysis was done at 0, 12, 24, 48, and 72 hours after injury. Results The aperture of the trajectory exit and entry were (5.00 ± 2.50) cm and (0.30 ± 0.15) cm immediately after injury. The wound surface was clean, rosy without leakage and swell ing after 72 hours in experimental group; wound and adjacent tissue were swell ing obviously, pus, muscle necrosis and exfol iative tissue was observed, and deep defect cavity at the trajectory exit could be seen in control group. MRI showed that pairs of l inear low signal in T1WI and T2WI was seen in trajector of experimental group at 5 hours after injury, and signal in T1WI gradually increased at disrupted area and tissue deformation area at 24, 48, and 72 hours; in control group, low signal in T1WI was observed at 5 hours after injury, and signal in T2WI gradually increased and a clear boundari between edema and surrounding tissue, and the increase of signal in T1WI was not obvious at 24, 48, and 72 hours. The histological observation showed that wound was dominated by effusion at 5 hours after injury, granulation tissue gradually increased, muscle tissue dissolved and inflammatory cell infiltration was not obvious at 24, 48, and 72 hours in experimental group; in control group, the gradual dissolution of muscle fibers and inflammatory cell infiltration were observed at 5, 24, and 48 hours, muscle tissue became swell ing, dissolving and degeneration and a large number of inflammatory cell infiltration gathered into the bacteria group at 72 hours. There was no significant difference in the number of bacteria per gram of tissue (P gt; 0.05) between experimental group and control group at 0 hour after injury; the numbers of bacteria in control group were significantly higher than those in experimental group at 12, 24, 48, and 72 hours (P lt; 0.05). Conclusion MRI combined with pathology show diagnostic meaning in treatment of gunshot wound with VSD. MRI can accurately reflect the scope of l imb gunshot wound 72 hours after injury. VSD may be an approach to delay infective time, shorten wound heal ing time, and promote the growth of healthy granulation tissue.
Objective To investigate the situation of MRI examination in children in outpatient and inpatient departments of the Sichuan Provincial People’s Hospital from 2010 to 2012, so as to provide favourable basis for the choice of imaging examination in children. Methods The materials of electronic reports of MRI examination in paediatric inpatient and outpatient departments from 2010 to 2012 were collected, categorized, and analyzed. Results a) 2 148 children underwent MRI examination in the Sichuan Provincial People’s Hospital from 2010 to 2012. The total number of patients increased with year. Boys were more than girls. The positive incidence was slightly decreased. The number of outpatients was more than inpatients, but the positive incidence was lower in outpatients. b) The total numbers of examination position were increased with year and the number of single position examination was the most (accounted for than 85% of the total numbers). The main examination positions included: head, MRA of the head, cervical column, knees, lumbar column, pituitary gland, thoracic column, and abdomen. The examination positions diversified gradually. The application of examination technique also increased gradually. c) The systemic disease spectrum of positive cases in MRI examination included 9 categories, which accounted for 42.86% of ICD-10. The nervous systematic disease, muscle, skeleton and connective tissue disease were the categories. The major disease types were stable during the recent 3 years. The increase was obvious in injuries of the knees, malacosis and atrophy of the brain, the deformity of the brain. Conclusion The total numbers of the patients and positions examined increased gradually with year in the Sichuan Provincial People’s Hospital from 2010 to 2012. The applications of MRI in the head, limbs and joints, and soft tissues were more extensive. Children diagnosed as positive results had diseases of the central nervous system, limbs and joints, and connective tissue disease.
ObjectiveTo study the difference of femoral condylar twist angle (CTA) measurement in three dimensional (3-D) reconstruction digital models of human knee joint based on the two dimensional (2-D) images of MRI and CT so as to provide a reference for selecting the best method of CTA measurement in preoperative design for the femoral prosthesis rotational position. MethodsThe CTA of 10 human cadaveric knee joint was measured in 3-D digital models based on MRI (group A), in 3-D digital models based on CT (group B), in the cadaveric knee joint with cartilage (group C), and in the cadaveric knee joint without cartilage (group D), respectively. The statistical analysis of the differences was made among the measurements of the CTA. ResultsThe CTA values measured in 3-D digital models were (6.43±0.53)° in group A and (3.31±1.07)° in group B, showing significant difference (t=10.235, P=0.000). The CTA values measured in the cadaveric knee joint were (5.21±1.28)° in group C and (3.33±1.12)° in group D, showing significant difference (t=5.770, P=0.000). There was significant difference in the CTA values between group B and group C (t=5.779, P=0.000), but no significant difference was found between group A and group C (t=3.219, P=0.110). ConclusionThe CTA values measured in the 3-D digital models based on MRI are closer to the actual values measured in the knee joint with cartilage, and benefit for preoperative plan.
Objective To study the MRI diagnosis of sacral fracture with sacral neurological damage and its cl inical appl ication. Methods From October 1999 to October 2007, 20 cases of sacral fracture (Denis classification, Type II)with sacral neurological damage were examined by obl ique coronal MRI of sacrum to show the whole length of sacral nerve. There were 17 males and 3 females, aged 30-55 years. The time from injury to hospital ization varied from 1 day to 23 months. The injury was caused by traffic accident in 10 cases, smash of heavy object in 8 cases and crush in 2 cases. Eight cases were accompanied by pubis fracture and 4 cases by urethral disruption. All patients accepted the examination of X-ray, CT and spiral CT 3D reconstruction. X-ray showed the displacement of fracture fragment was backwards and upwards, and sacral-hole l ine was vague, asymmetric and distorted. CT showed that sacral neural tube was left-right asymmetry, the displacement of fracture fragment was backwards and upwards, combining with the compression and intruding to sacrum center at different section levels. The cl inical manifestations, international standards for Neurological Classification of Spinal Cord Injury recommended by American Spinal Injury Association International Spinal Cord Society, comparison between normal and abnormal MRI and Gierada’s results were the basis for cl inical diagnose and MRI diagnose, which was confirmed by operation. Results Nerve injury diagnosed by cl inical manifestation were S1 (17 cases), S2 (14 cases), S3 (7 cases), and S4 (6 cases). Nerve injury diagnosedby MRI were S1 (17 cases), S2 (14 cases), S3 (3 cases), and S4 (2 cases). Nerve injury confirmed by operation were S1 (17 cases), S2 (14 cases), S3 (7 cases), and S4 (1 case). Obl ique coronal MRI of sacrum showed the whole length of sacral nerve and its adjacent relationship, detecting bone fragment compression and route alteration of never were evident in 5 cases, the fat disappearance around the site of nerve root injury in 19 cases, narrowness of sacral nerve canal in 17 cases and the abnormally enlarged sacral nerve in 11 cases. Conclusion Obl ique coronal MRI of sacrum is of great value in the local ization and the qual itative diagnosis of sacral neurological damage.