Two novel parameters to evaluate the influence of the age and gender on the anatomic relationship of the atlas and axis in children no more than 8 years old: imaging study.

PURPOSE: Because of the complex cervical vertebral embryology and some normal variations, the atlantoadental interval (ADI) was not suitable for the evaluation of the anatomic relationship between the atlas and axial in children less than 2 years old. And the influence of the age and gender on the anatomic relationship between atlas and axial in children was still unclear. Two novel parameters, atlas-axis anteroposterior distance (AAAD) and atlas-axis lateral distance (AALD), were invented to evaluate the anatomic relationship between the atlas and axis in the children no more than 8 years old with different age and gender. METHODS: Cross-sectional computed tomography (CT) scans of the atlantoaxial joint for 140 randomly selected pediatric patients no more than 8 years old were analyzed. On the ideal CT reconstruction images, AAAD, AALD, atlantoaxial lateral bending angle (AALB), and atlantoaxial rotation angle (AARA) were measured. RESULTS: There was no statistically significant difference between the mean AAAD in different age and gender groups. The 99% confidence interval for AAAD was 7.12-7.82 mm. There was no significant correlation between AAAD and AALB/AARA and AALD and AALB/AARA. CONCLUSION: The AAAD was less than 7.12 mm or much than 7.82 mm that suggested a possible instability in the atlantoaxial joint and could help the diagnosis of the atlantoaxial instability in children no more than 8 years old. There was no difference between the mean AAAD of pediatric patients no more than 8 years old in different age and gender groups.

L5-S1 disc degeneration and the anatomic parameters of the iliac crest: imaging study.

PURPOSE: To evaluate the relationship between height ratio of the iliac crest to L4 (HR), width ratio of the iliac crest to L4 (WR) and L5-S1 disc degeneration. METHODS: On T2-weighted sagittal images of the 50 randomly selected patients, two observers graded L5-S1 discs and some other parameters were measured. Then, relative signal intensity (RSI) of the L5-S1 nucleus pulposus was calculated. On anteroposterior and lateral radiographs of the same 50 patients' lumbar spine, the parameters such as the height of the iliac crest were measured and then HR and WR were calculated. Finally, HR, WR and the percentage of the sROM of L5-S1 in L1-S1 segments of the other 51 randomly selected patients were calculated. RESULTS: Positive correlations were found between HR, WR and RSI of the L5-S1 disc. Negative correlations were found between HR, WR and modified Pfirrmann scores of L5-S1 nucleus pulposus. A statistically significant negative correlation was found between HR and the percentage of sROM of L5-S1 in L1-S1 segments. CONCLUSIONS: Low HR and (or) WR were the risk factors for L5-S1 disc degeneration. High HR could reduce the percentage of sROM of L5-S1 in L1-S1 segments and high HR and (or) WR could reduce the incidence of L5-S1 disc degeneration.

[Diagnostic value of magnetic resonance imaging in special-site ectopic pregnancy].

OBJECTIVE: To explore the magnetic resonance imaging (MRI) features and diagnostic value of special-site ectopic pregnancy. METHODS: The MRI features of special-site ectopic pregnancy on 39 pathologically confirmed cases were retrospectively analyzed. All cases received ultrasonic inspection, MRI plain scan and 11 cases underwent enhanced scan. RESULTS: In 39 cases, there were 3 cases of interstitial tubal pregnancy (n = 3), cornual pregnancy (n = 8) and uterine scar pregnancy (n = 28). The accuracy rates of location and diagnosis were 94.9% and 82.1% respectively. And they were both higher than the rates of ultrasound. They were classified into two groups by clinical outcomes:pregnancy and miscarriage. In 22 cases of pregnancy, there were sac in sac (n = 9) and complete fertilized egg (n = 13). In 17 cases of miscarriage, there were irregular honeycomb (n = 7), ring (n = 6) and mass (n = 4). Among 11 enhanced cases, there were significant enhancement (n = 4), flake or cord-like enhancement (n = 5), a little strengthen on edge (n = 1) and no enhancement (n = 1). The group had intrauterine decidual tissue hyperplasia (n = 22), ovarian cyst (n = 8), pelvic fluid (n = 6), adenomyosis (n = 3), fibroid (n = 2), endometriosis in pelvic and abdominal wall scar area (n = 1) and mild hydrops in right kidney and ureter (n = 1). CONCLUSION: The MRI features of special-site ectopic pregnancy are characteristic and important for clinical treatment.

The influence of cervical spine position on the three anterior endoscopic approaches to the craniovertebral junction: an imaging study.

BACKGROUND CONTEXT: Three endoscopic anterior approaches, the transnasal, transoral, and transcervical approaches, are used for ventral lesions of the craniovertebral junction and have been compared regarding surgical working distances and approach angles. However, how the position of the cervical spine influences the depths of surgical corridors and approach angles for the three approaches has not been evaluated. PURPOSE: To evaluate the depths of surgical corridors and the approach angles for the three endoscopic approaches, taking the influence of cervical spine position into account. STUDY DESIGN: A radiographic study comparing three anterior endoscopic approaches to the craniovertebral junction. PATIENT SAMPLE: Cervical extension and flexion radiographs for 34 patients and cross-sectional computed tomography scans for 30 additional patients were assessed. OUTCOME MEASURES: The depths of the surgical corridors and the approach angles for the three endoscopic approaches in the midsagittal planes. METHODS: We determined the mean angles of the surgical trajectories for the endoscopic transoral and transcervical approaches on cervical extension and flexion radiographs. In addition, we measured the depths of the surgical corridors and the approach angles for the three approaches in the midsagittal plane. RESULTS: The average depths of surgical corridors were as follows: endonasal, 93.65 mm; transoral, 85.27 mm; transcervical, 62.97 mm (in extension). The average approach angles were as follows: endonasal, 31.22°; transoral, 30.87°; transcervical, 36.58° (in extension). CONCLUSIONS: The position of the cervical spine does not influence the surgical convenience of the endoscopic transnasal approach, but it can influence the endoscopic transoral and transcervical approaches, especially the latter. The endoscopic transcervical approach offers several advantages over the endoscopic transoral and endonasal approaches.

The diagnostic value of multislice computed tomography in children with congenital lobar emphysema.

OBJECTIVE: To investigate the diagnostic value of multislice computed tomography (MSCT) in children with congenital lobar emphysema (CLE). MATERIALS & METHODS: Seven children with CLE diagnosed by surgery pathology had undergone thin-slice scanning of MSCT, multiplanar reconstruction and volume rendering technique. The diagnostic value of MSCT in children with CLE was evaluated. RESULTS: Among seven patients with CLE, three cases were located in the left upper lobe, two cases in the right upper lobe and two cases in the right middle-upper lobe. All cases were manifested by variable degrees of bronchus stenosis in the corresponding lung segment or lobe, increased lung radiolucence and volume, and reduced lung markings. In this group, there was one case, respectively, associated with left posterior mediastinal bronchogenic cyst, bronchiectasis in the right lung, a lung cyst in the right upper lobe, angiodysplasia in the right upper lung and congenital funnel chest; two cases of multiple lung bullae in the right lung, three cases of infection in both lungs and four cases of mediastinal hernia. CONCLUSION: MSCT and multidimensional reconstruction is a noninvasive diagnostic method that displays the location, degree and accompanying anomalies of CLE in three dimensions. It has significance for clinicians in that it reduces both misdiagnosis and the time taken to receive treatment.

[Study on the diagnostic value of imageology of giant cell tumour of tendon sheath].

OBJECTIVE: To investigate the diagnostic value of imageology of giant cell tumour of tendon sheath (GCTS) including X-ray, CT and MRI. METHODS: Thirty-five patients with GCTTS confirmed by operation and pathology were retrospectively analyzed. There were 16 males and 19 females. The average age was 39.4 years, ranged from 7 to 66 years. All the patients underwent X-ray examination, 8 patients underwent CT examination, and 16 patients underwent MRI examination. RESULTS: There were 2 patients in knee joint, 6 patients in ankle joint, 1 patient in capitulum radius, 2 patients in wrist joint, 14 patients in hand and 10 patients in foot. Ten cases were the diffuse form, and 25 cases were the focal form. The X-ray results: the slightly high density soft tissue mass surrounding the bone were shown in 32 cases, 3 cases were normal. The bone erosion were shown in 9 cases, the obvious destruction of bone were shown in 5 cases. CT results: The soft tissue mass and the destruction of bone were shown clearly. MRI results: On T1WI, the signal intensity of GCTTS almost was similar to those of skeletal muscle in 9 cases and was slightly lower than those of skeletal muscle in 7 cases. On T2WI, the signal intensity presented mainly hypointensity with patchy isointensity or hyperintensity signal. A little of fluid was shown in 6 cases. CONCLUSION: X-ray can demonstrate the lesion and erosion of bone, destruction of bone can clearly be shown on CT. The low intensity signal on MRI T1WI and T2WI is the characteristic appearance of GCTTS. And it can clearly show the lesion range and type of GCTTS.