[Study on the overall anatomical features and clinical value of lumbar nerve root, plexus and branches in CT reconstruction].

OBJECTIVE: To identify the overall anatomical characteristics and the clinical value of the lumbar nerves under CT multiplanar reconstruction. METHODS: Fifty normal subjects and 30 patients with LN diseases (51 sides) were selected, including 10 patients with lumber intervertebral disk hernia, eight patients with spinal stenosis, 5 patients with spondylolisthesis, 1 patient with tethered cord syndrome, 1 patient with lumbar scoliosis, and 5 patients with spinal trauma The 16-slice helical CT (Light Speed, GE Company) was used for scanning the lumbar vertebra with multiplanar reconstruction in Workstation (ADW4.1) with UNIX System in DICOM format. The image was set on the same slice for the overall anatomy and manifestations of the lesions. RESULTS: The same-slice imaging showed the strip-like LN slightly lower than the surrounding muscle in density. Each LN went out of the dural sac at an acute angle. The course of the lumbar plexus and its major branches, including the obturator nerve, femoral nerve and reproductive nerve, and their relations to the adjacent structures were clearly revealed. The percentage of the segments displayed was well associated with the reconstruction angle, with the order being oblique coronal > outward-rotated oblique coronal > oblique sagittal > coronal > sagittal section. The major manifestations of abnormal LN included compression and displacement (50 sides, 98.0%), morphological changes (49 sides, 96.1%), adhesion (41 sides, 80.4%). CONCLUSIONS: The CT multiplanar reconstruction is ideal for the imaging of the overall size, shape, running and tension of the LN root; it is valuable in clinical diagnosis.

[Features of obturator nerve by high-resolution CT at the same slice with multiplanar planar reconstruction techniques and clinic value thereof].

OBJECTIVE: To explore the features of obturator nerve (ON) by high-resolution CT (HRCT) at the same slice with multiplanar planar reconstruction techniques and clinic value thereof. METHODS: The normal lumbar vertebral bodies of 60 healthy adults and the abnormal lumbar vertebral bodies of 31 patients with ON disorders were scanned with 16-slice spiral CT, multiplanar reconstruction was conducted in the Workstation ADW4. 1, with UNIX system and DICOM form. The images at the same slice were studied. RESULTS: The shapes, thickness, direction, length, adjourning relationship, and tension could be shown at the same slice of oblique and coronal section or oblique and sagittal plane with rotation in external sides on the way from the starting point of dural sac to foramen obturatum in pelvis, meanwhile the manifestations of abnormal ON also could be shown. CONCLUSION: The anatomical features and abnormal manifestation of ON at the same slice with 16-slice spiral CT using the multiplanar reconstruction techniques can be fully shown from the starting point of dural sac to the foramen obturatum in pelvis. This technique is very important in diagnosis and treatment of diseases of obturator nerve.

[Value of multiplanar reconstruction of lumbar nerve roots on the same level by high resolution computed tomography in diagnosis of lumbar disc herniation and/or bulge].

OBJECTIVE: To explore value of multiplanar reconstruction of lumbar nerve roots on the same level by high resolution computed tomography (HRCT) in diagnosis of lumbar disc herniation and/or bulge (LDHB). METHODS: Thirty-one patients with manifestations of typical nerve root compression, such as lumbago and tenderness of percussion pain at the corresponding sites were scanned with 16-slice spiral CT and multiplanar reconstruction of lumbar nerve roots on the same level with the workshop ADW4.150, and were diagnosed as with LDHB with 50 segments. The diagnoses were confirmed by operation later. RESULTS: This technique showed not only the existence of LDHB but also the signs of nerve root compression, including the touch of nerve roots with the LDHB (100%), translocation of nerve roots (96%), morphological change (94%), changes of diameter (92%), changes of direction (88%), changes of density (80%), increase of the angle between the dural sac and nerve root (76%), etc. Along with the prolonging of time, the nerve roots became thinner in all segments. CONCLUSION: Multiplanar reconstruction of lumbar nerve roots on the same level by high resolution computed tomography is valuable in the diagnosis of lumbar disc herniation and/or bulge.

Overall anatomical features and clinical value of the sacral nerve in high resolution computed tomography reconstruction.

BACKGROUND: Sacral nerve injury is a common complication of pelvic or sacral fractures. As the sacral nerve courser within the sacrum and has a complex relationship with the surrounding tissues, different parts of the sacral plexus injury have similar clinical symptoms and signs. Since lack of specific imaging technique in the diagnosis of sacral nerve injury, especially on multi-segment, multi-site, how to determine the preoperative location and extent of the sacral nerve injury accurately becomes a concern of the general orthopaedic and images practitioners. This study was conducted to gain an insight into the overall anatomical features of the sacral nerve (SN) on the same slice in high resolution computed tomography (HRCT) reconstruction and to determine the value of this information for the clinical diagnosis of related diseases. METHODS: Fifty healthy volunteers and 30 patients (40 sides) with SN lesions confirmed by surgery were scanned using a 16-slice helical CT scanner (Light Speed, GE, USA). Among the patients, 6 with intervertebral disk hernia (6 sides), 8 with spinal stenosis (12 sides), 11 with pelvic trauma (14 sides), 4 with pelvic malignancies (6 sides), and 1 with sacral vertebral tuberculosis (2 sides). The SN multiplanar reconstruction was performed using a UNIX-based SCD4.1 workstation where the image was set on the same slice. All images were stored in the Digital Imaging and Communications in Medicine format. The display of nerves in different sections was analyzed using a five-graded scale with coordinate curves of each individual score. The overall anatomic features visible on the slice were analyzed and the abnormalities of the lesions were studied. RESULTS: The image of the same slice clearly revealed the shape, running direction, thickness, tension and adjacent anatomy of the S1-S4 nerves. The rank of display rates in different sections was: outward-rotated oblique sagittal > outward-rotated oblique coronal > oblique coronal plane > coronal > sagittal > transverse section. The S5 nerve was partially displayed from the starting point to the segment around the posterior sacral foramen. The overall anatomy of the triangular sacral plexus was only revealed in the oblique outward-rotated sagittal section, while 100% of its individual rami, as well as two or three of the adjacent rami, were displayed from their starting points to the anterior border of the piriformis. The abnormalities included 39 sides of morphological change (97.5%), 38 sides of compression (95.0%), 35 sides of adhesion (87.5%), 32 sides of displacement (80.0%), 34 sides of shrinkage (85.0%), 6 sides of thickening (15.0%), and 2 sides of abruption (5.0%). CONCLUSIONS: The 16-slice CT multiplanar reconstruction was able to reveal the overall anatomic features of the SN on the same slice. The section of reconstruction was a crucial factor in determining the display capability of various sacral nerves. This technology was valuable in the diagnosis and management of related diseases.