Cervical spine surgery performed for the correct indications yields good results. However, surgeons need to be mindful of the many possible pitfalls. Complications may occur starting from the anaesthestic procedure and patient positioning to dura exposure and instrumentation. This review examines specific complications related to anterior and posterior cervical spine surgery, discusses their causes and considers methods to prevent or treat them. In general, avoiding complications is best achieved with meticulous preoperative analysis of the pathology, good patient selection for a specific procedure and careful execution of the surgery. Cervical spine surgery is usually effective in treating most pathologies and only a reasonable complication rate exists.
Pathology ; Patient Positioning ; Patient Selection ; Spine*

The posterolateral approaches to the spine is an effective method for the neural decompression and the spinal stabilization. This procedure has an advantages of an one-stage posterolateral decompression-stabilization. We have experienced 8 patients with burst fracture in the thoracolumbar junction. A three-quater prone position was used for patient positioning. No patient showed neurologic deterioration after surgery. Patient positioning and the operative approach are described and illustrated.
Decompression* ; Humans ; Patient Positioning ; Prone Position ; Spine*

To generate on-board digital tomosynthesis (DTS) for three-dimensionalimage-guided radiation therapy (IGRT) as an alternative to conventional portal imaging or on-board cone-beam computed tomography (CBCT), two clinical cases (liver and bladder) were selected to illustrate the capabilities of on-board DTS for IGRT. DTS images were generated from subsets of CBCT projection data (45, 162 projections) using half-fan mode scanning with a Feldkamp-type reconstruction algorithm. Digital tomosynthesis slices appeared similar to coincident CBCT planes and yielded substantially more anatomic information. Improved bony and soft-tissue visibility in DTS images is likely to improve target localization compared with radiographic verification techniques and might allow for daily localization of a soft-tissue target. Digital tomosynthesis might allow targeting of the treatment volume on the basis of daily localization.
Cone-Beam Computed Tomography ; Humans ; Patient Positioning

PURPOSE: To evaluate and analyse the operative results of percutaneous iliosacral screw fixation in displaced posterior pelvic ring injuries. MATERIALS AND METHODS: Fourteen consecutive patients with displaced posterior pelvic ring injuries (August 1995-June 1998) treated by percutaneous iliosacral screw fixation were reviewed. We analysed the pattern of fracture, associated injury and method of operation including patient's position, complication and functional result. RESULTS: Seventeen iliosacral screws under fluoroscopic guidance were applied in fourteen patients. During the operations various positions of patients were possible, and all cases were treated with closed reduction and percutaneous iliosacral screw fixation except in one case (open reduction and percutaneous screw fixation). Fixation of associated anterior pelvic ring injury was undertakes in eight cases. Screw-related neurovascular injury and other complications such as breakage, loosening, misplacement and redisplacement, nonunion and screw site infection during follow-up period were not found. Satisfactory clinical and radiologic results were achieved during follow-up period except in one case (limping due to leg length discrepancy, malreduction) in this study. CONCLUSION: Precise understanding of iliosacral anatomy and its variants, proper patient positioning and appropriate intraoperative interpretation of fluoroscopic iliosacral image are mandatory. We believe percutaneous iliosacral screw fixation is a useful addition to treatment options for unstable posterior pelvic ring injury.
Follow-Up Studies ; Humans ; Leg ; Patient Positioning

PURPOSE: Conventional radiation therapy portal images gives low contrast images. The purpose of this study was to enhance image contrast of a linacgram by developing a low-cost image processing method. MATERIALS AND METHODS: Chest linacgram was obtained by irradiating humanoid phantom and scanned using Diagnostic-Pro scanner for image processing. Several types of scan method were used in scanning. These include optical density scan, histogram equalized scan, linear histogram based scan, linear histogram independent scan, linear optical density scan, logarithmic scan, and power square root scan. The histogram distribution of the scanned images were plotted and the ranges of the gray scale were compared among various scan types. The scanned images were then transformed to the gray window by pallette fitting method and the contrast of the reprocessed portal images were evaluated for image improvement. Portal images of patients were also taken at various anatomic sites and the images were processed by Gray Scale Expansion (GSE) method. The patient images were analyzed to examine the feasibility of using the GSE technique in clinic. RESULTS: The histogram distribution showed that minimum and maximum gray scale ranges of 3192 and 21940 were obtained when the image was scanned using logarithmic method and square root method, respectively. Out of 256 gray scale, only 7 to 30% of the steps were used. After expanding the gray scale to full range, contrast of the portal images were improved. Experiment performed with patient image showed that improved identification of organs were achieved by GSE in portal images of knee joint, head and neck, lung, and pelvis. CONCLUSION: Phantom study demonstrated that the GSE technique improved image contrast of a linacgram. This indicates that the decrease in image quality resulting from the dual exposure, could be improved by expanding the gray scale. As a result, the improved technique will make it possible to compare the digitally reconstructed radiographs (DRR) and simulation image for evaluating the patient positioning error.
Head ; Humans ; Knee Joint ; Lung ; Neck ; Patient Positioning ; Pelvis ; Thorax

PURPOSE: This study was performed to evaluate the general anatomy and morphology of the nasopalatine canal using cone-beam computed tomography (CBCT) and to determine the human anatomic variability of the nasopalatine canal in relation to age and gender. MATERIALS AND METHODS: The study included 100 subjects aged between 20 and 86 years who were divided into the following 3 groups: 1) 20-34 years old; 2) 35-49 years old; 3) > or =50 years old. The subjects were equally distributed between the genders. CBCT was performed using a standard exposure and patient positioning protocol. The data of the CBCT images were sliced in three dimensions. Image planes on the three axes (X, Y, and Z) were sequentially analyzed for the location, morphology and dimensions of the nasopalatine canal by two independent observers. The correlation of age and gender with all the variables was evaluated. RESULTS: The present study did not reveal statistically significant differences in the number of openings at the nasal fossa; diameter of the nasal fossa openings; diameter of the incisive fossa; shape, curvature, and angulation of the canal as viewed in the sagittal sections; antero-posterior dimensions and length of the canal in the sagittal sections; or the level of division of the canal in the coronal plane by age. However, males and females showed significant differences in the length of the canal in the sagittal sections and level of the division of the canal in the coronal plane. CONCLUSION: The present study highlighted important variability observed in the anatomy and morphology of the nasopalatine canal.
Cone-Beam Computed Tomography* ; Female ; Humans ; Male ; Patient Positioning

PURPOSE: The altered gantry angle during scanning for some multiplanar reconstruction CT program (CT/MPR) may cause distortion of the image. The aim of this study was to ascertain whether there is a image distortion in a reformatted image when the gantry and the object are equally inclined using ToothPix and DentaScan program. MATERIALS AND METHODS: A resin block model with four cylindrical holes and a human dry mandible were used. Two MPR software packages, ToothPix and DentaScan program, were used for reformatted panoramic images. The block and the gantry were equally inclined at 0degree, 15degrees, and 30degrees. RESULTS: With ToothPix program, a resin block model with empty holes and a dry mandible showed inclined images in the reformatted panoramic image. Increasing the gantry angle, the depth and inclination of the holes were increased in the reformatted central panoramic images. However, a resin block model with gutta percha in its holes and a dry mandible with a wire in its mandibular canal didn't show image distortion. With DentaScan program, image distortion was not seen in any situation. CONCLUSION: ToothPix program may distort the reformatted image when the gantry angle is not at zero degrees. However, with DentaScan program, the patient may be positioned comfortably and the gantry can be adjusted to the patient positioning.
Dental Implants ; Gutta-Percha ; Humans ; Mandible ; Patient Positioning

We have treated thirteen complex plateau fractures involving both condyles with one of the following conditions with the use of the combined anterior and posterior approaches in a modified supine position. Associated PCL avulsion fracture, displacement of major fracture plane dominantly at the back, large coronal fracture fragment involving medial or lateral condyles. A patient is placed on an operation table in supine position with a bump under the contralateral buttock. The well leg is placed in a lithotomy position and the injured leg is placed over a sterilized Mayo stand separately. For the posterior approach the table was tilt toward the injured side with the hip abducted and rotated externally. With a modified patient's positioning we were able to use combined anterior and posterior approaches simultaneously for the management of certain complex plateau fractures without changing the draping.
Buttocks ; Hip ; Humans ; Leg ; Operating Tables ; Patient Positioning* ; Supine Position

Gastric emptying scintigraphy has long been the standard method for measuring gastric motility. Various methodologies for this study have been used including meal composition, patient positioning, instrumentation, frequency of data acquisition, study length and quantitative method. For accurate quantification, it is not important which method is in use, except that the methodology should always be the same and normal values need to be derived and validated for that methodology.
Gastric Emptying ; Meals ; Patient Positioning ; Reference Values ; Stomach

Humans ; COVID-19 ; Prone Position ; SARS-CoV-2 ; Patient Positioning