Multiplanar Computed Tomography Images Research Articles

Analysis of Cochlear Morphology for Cochlear Implantation Using Three-Dimensional Reconstruction of Computed Tomography Images

Plain Language SummarySubjects suffering from sensorineural deafness have been able to regain partial hearing and speech understanding using cochlear implants. The frequency mapping of the cochlea is important for postoperative success. However, the frequency distribution of the human cochlea varies among individuals due to variations in cochlear length. Accurate measures of cochlear duct length for preoperatively defining this length are needed to maximize the effect of frequency mapping. This study analyzed the length and shape of the cochlea using three-dimensional reconstructions of the temporal bone based on computed tomography scans. Eight angular points (P0–P7) every 90° were selected from 0° to 630° from the center of the round window using the reconstructed cochlear canal images. The radius (R) and thickness (T) of the cochlear canal at each point were measured. Each point was theoretically positioned 90° relative to the origin starting from the center of the round window. Therefore, P0 and P7 are the angular points at 0° and 630°, respectively. The coiling ratio of the cochlea was measured using the ratios R4/R0, R5/R1, R6/R2, and R7/R3. The cochlear canal length (CoCL) was estimated using an equation based on the radius at each point. The mean CoCL from 0° to 630° was 31.5 mm, and the cochlear volume was 55.9 mm3. Based on the Greenwood and Erixon equations, our CoCL 360° and 630° measurements corresponded to frequencies of 982 (759–1,405) Hz and 312 (158–499) Hz. These are comparable with previously reported values.

Sinonasal Anatomy

It is imperative for all imaging specialists to be familiar with detailed multiplanar computed tomography imaging anatomy of the paranasal sinuses and adjacent structures. This article reviews, in brief, the radiologically relevant embryology of the sinonasal region and discusses the imaging anatomy of the nasal cavity and paranasal sinuses. Radiologists should understand the importance and clinical implications of identifying the numerous anatomic variations encountered in this region and prepare a structured report that provides a surgical road map to the referring clinician.

Computed Tomographic Assessment of Age- and Gender-Specific Sagittal Lumbopelvic Alignment in a Japanese Population.

Introduction Previous studies have reported differences in lumbopelvic alignment between standing and supine positions. Computed tomography (CT) images taken in the supine position are often used for clinical studies in addition to standing radiographs, although not frequently. Our study aims to clarify normative values of CT-evaluated lumbopelvic parameters and the characteristics of age- and gender-related lumbopelvic alignment in the supine position. Methods Patients undergoing CT scans of abdominal or lumbar regions for reasons other than low back disorders were included (n=581). Sagittal multiplanar reconstruction CT images were obtained, and lumbar lordosis (LL), L5-S1 angle, and sacral slope (SS) were measured. Mean values of the parameters in patients aged 59 years and under, 60-69, 70-79, and 80 and over, and in males and females, were calculated. Age- and gender-related differences in these parameters were statistically analyzed. Results Among the four age groups, patients 80 years and over showed significantly lower LL and SS than patients aged 70-79. Females 80 years and over showed significantly lower LL and SS than all other age groups, but those in males did not. The comparison between males and females showed no significant differences in LL and SS; however, the L5-S1 angle was significantly higher in males than in females. In patients 80 years and over, females showed significantly lower LL and SS than in males. Conclusions This study provides normative CT-evaluated lumbopelvic parameters, such as LL, L5-S1 angle, and SS, which will be utilized for comparisons in future studies. The present study first revealed that pelvic retroversion and lumbar kyphosis occur in elderly females in the supine position, which raised a possibility that age-related decrease of LL and SS in females occurs at an older age in the supine position than in the standing position.

Use of tracheobronchial tree 3-dimensional printed model: does it improve trainees\u2019 understanding of segmentation anatomy? A prospective study

BackgroundThis prospective study investigated whether the use of 3D-printed model facilitates novice learning of radiology anatomy on multiplanar computed tomography (CT) when compared to traditional 2D-based learning tools. Specifically, whether the use of a 3D printed model improved interpretation of multiplanar CT tracheobronchial anatomy.MethodsThirty-one medical students (10F, 21 M) from years one to three were recruited, matched for gender and level of training and randomized to 2D or 3D group. Students underwent 20-min self-study session using 2D-printed image or 3D-printed model of the tracheobronchial tree. Immediately after, students answered 10 multiple-choice questions (Test 1) to identify tracheobronchial tree branches on multiplanar CT images. Two weeks later, identical test (Test 2) was used to assess retention of information. Mean scores of 2D and 3D groups were calculated. Student’s t test was used to compare mean differences in tests scores and analysis of variance (ANOVA) was used to assess the interaction of gender, CT imaging plane and time on test scores between the two groups.ResultsFor test 1, 2D group had higher mean score than 3D group although not statistically significant (7.69 and 7.43, p = 0.39). Mean scores for Test 2 were significantly lower than for Test 1 (7 and 7.57, p = 0.03) with mean score decline for 2D group (Test 1 = 7.69, Test 2 = 6.63, p = 0.03), and similar score for 3D group (Test 1 and 2 = 7.43). There was no statistically significant interaction of gender and test score over time. Significant interaction between group and time of test was found for axial CT images but not for coronal images.ConclusionsUse of a 3D-printed model of the tracheobronchial anatomy had no immediate advantage over traditional 2D-printed images for learning CT anatomy. However, use of a 3D model improved students’ ability to retain learned information, irrespective of gender.

Benefits of the multiplanar and volumetric analyses of pancreatic cancer using computed tomography.

Although pancreatic cancer tumors are irregularly shaped in terms of their three-dimensional (3D) structure, when T staging by imaging results, generally only the axial plane is used to measure the largest tumor diameter. We investigated the size of pancreatic cancer tumors using multi-plane and 3D reconstructed computed tomography (CT) images and investigated their clinical usefulness. Patients who underwent surgery for pancreatic adenocarcinoma were included. We measured the largest diameter of each pancreatic tumor in the axial, coronal, and sagittal planes of CT images. In addition, maximal diameter and cancer volume were measured from 3D images that were constructed using a semi-automated software system. Final data were compared with pathologic examination and the effect of each value on prognosis was analyzed. A total of 183 patients were analyzed. The maximal diameters measured on the axial, coronal, and sagittal planes were 2.9 ± 1.1, 3.2 ± 0.9, and 3.2 ± 1.0 cm, respectively, which were significantly smaller than pathologic results (3.4 ± 1.4 cm, all p<0.05 by paired t-test). The longest diameter among them (3.4 ± 1.1 cm) was nearly similar to the pathologic diameter. Cancer volume measured on 3D images demonstrated a higher area under the receptor operating characteristic curve [0.714, (95% confidence interval: 0.640–0.788)] for predicting early death compared to any unidimensional CT diameters measured. The longest pancreatic tumor diameter measured on multiplanar CT images was most accurate when compared to its corresponding pathologic diameter. Tumor volume had a stronger correlation with overall survival than tumor diameter.

Radiologic Characteristics of Anterior Transarticular Crossing Screw Placement for Atlantoaxial Joint Instability

The feasibility of anterior transarticular crossing screws (ATCS) was confirmed in cadaveric specimens and it has been used in clinic. However, no study has documented the morphometric characteristics of ATCS. This study seeks to determine the morphometric characteristics of ATCS in C1-C2 fixation. A total of 100 patients without abnormality of C1-2 were enrolled. The range of screw lateral angles (LAs) and the screw lengths of ATCS on coronal images were measured on multiplanar computed tomography images, as well as the screw incline angles (IAs) in the sagittal plane. The ideal trajectory was designed as toward to the posterosuperior points of the opposite C1 lateral mass, which had the longest screw. The LAs were relatively small in men (31.4°-45.3°) compared with women (32.6°-46.0°). In the sagittal plane, the IAs were ranged from 41.0° to 68.4° in men and from 44.4° to 68.1° in women. The overall screw lengths were longer in men (34.7-44.8 mm) than in women (32.2-39.6 mm). In the ideal path, the LA and IA were 38.4° and 41.0° in men and 39.6° and 44.4° in women, and the screw lengths were 44.8 mm in men and 39.6 mm in women. This study provides the range of screw angles and lengths of ATCS, which will help surgeons to perform ATCS safely and accurately.

Column specific fixation for complex tibial plateau fractures – Midterm prospective study in South - Indian population

BackgroundTibial plateau fractures involving two or more columns were routinely assessed by two-dimensional radiography in the past. This often misled surgeons and attention was given only to the medial and lateral column without consideration of the posterior column, especially the postero-medial corner. Luo in 2010 introduced the new three-column classification system based on multiplanar computed tomography images. This study was conducted to assess the outcome after internal fixation of tibial plateau fractures involving two or more columns in our centre based on the column specific approach. Materials and MethodsThis was a prospective study conducted at our institute, between 2011 and 2016. Total of 183 patients with tibial plateau fractures involving two or more columns were admitted during this study period of which 123 patients were satisfied our inclusion criteria. 8 patients were lost to follow up. Hence 115 patients with tibial plateau fractures involving two or more columns were classified based on the new three column classification system. Dual column fixation (Anterolateral +Anteromedial) was done in 76 patients, (Anterolateral+Posteromedial) fixation in 25 patients and triple column fixation (Anterolateral + Anteromedial + Posteromedial) in 14 patients. Post operatively patients were assessed by Modified Rasmussen functional and radiological scoring system. ResultsBased on Modified Rasmussen functional scoring system, 73 patients (63.5%) had excellent results, 37 patients (32.2%) had good results and 5 patients (4.3%) had fair results. Based on Modified Rasmussen radiological scoring system, 71 patients (61.7%) had excellent results, 38 patients (33.1%) had good results, 6 patients (5.2%) had fair results. 3 patients had deep infections. ConclusionBased on our study, we like to conclude that we had good outcomes utilizing this modern column specific approach to the treatment of these two or more column tibial plateau fracture injuries, which includes assessment of three columns.

Applicability of color-coded computed tomography images in lung volume reduction surgery planning.

Adequate patient selection is the key to successful lung volume reduction in patients with pulmonary emphysema. Computed tomography (CT) enables a reliable detection of pulmonary emphysema and allows an accurate quantification of the severity. Our goal was to investigate the usefulness and reliability of color-coded (CC) CT images in classification of emphysema and preoperative lung volume reduction planning. Fifty patients undergoing lung volume reduction surgery at our institution between September 2015 and February 2016 were retrospectively investigated. Three readers visually assessed the amount and distribution patterns of pulmonary emphysema on axial, multi-planar and CC CT images using the Goddard scoring system and a surgically oriented grading system (bilateral markedly heterogenous, bilateral intermediately heterogenous, bilateral homogenous and unilateral heterogenous emphysema). Observer dependency was investigated by using Fleiss' kappa (κ) and the intraclass correlation coefficient (ICC). Results were compared to quantitative results from densitometry measurements and lung perfusion scintigraphy by using Spearman correlation. Recommendations for lung volume reduction sites based on emphysema amount and distribution of all readers were compared to removal sites from the surgical reports. Inter-rater agreement for emphysema distribution rating was substantial for CC images (κ=0.70; 95% CI, 0.64-0.80) and significantly better compared to axial and multiplanar images (P≤0.001). The inter-rater agreement for recommended segment removal was moderate for CC images (κ=0.56; 95% CI, 0.49-0.63) and significantly better compared to axial and multiplanar images (P<0.001). Visual emphysema rating correlated significantly with measurements from densitometry and perfusion scintigraphy in the upper and lower lung zones in all image types. CC CT images allow a precise, less observer-dependent evaluation of distribution of pulmonary emphysema and resection recommendation compared to axial and multiplanar CT images and might therefore be useful in lung volume resection surgery planning.

Anatomical variations of anterior ethmoidal artery at the ethmoidal roof and anterior skull base in Asians.

The variations of the anterior ethmoidal artery (AEA) in different populations should be recognized by surgeons to prevent unwarranted complications during surgery. The aim of this study was to assess the anatomical variations of AEA in Asian population. A cross-sectional study of 252 AEA identified by computed tomography (CT) of the paranasal sinuses. The multiplanar CT images were acquired from SOMATOM® Definition AS+ and reconstructed to axial, coronal and sagittal view at 1mm slice thickness. 42.5% of AEA was within skull base (grade I), 20.2% at skull base (grade II) and 37.3% coursed freely below skull base (grade III). The prevalence of supraorbital ethmoid cell (SOEC) and suprabullar cell (SBC) was 29.8% and 48.0%. The position of AEA at skull base has significant association with SOEC (p < 0.001), but not with SBC (p = 0.268). Type I Keros was 42.1% and Type 11 Keros was 57.9%. When lateral lamella's height is longer, the probability increases for AEA to course freely within the ethmoid sinus (p = 0.016). The mean distance of AEA from skull base was 1.93 ± 2.03mm, orbital floor 21.91 ± 2.47mm and nasal floor 49.01 ± 3.53mm. The position of AEA at skull base depends on the presence of SOEC and length of lateral lamella, but not with SBC. When compared to European population, the mean distance between AEA and nasal floor is shorter in Asians.

Near miss for big red: a unique case of penetrating glass injury of the thoracic spine and posterior mediastinum.

A 42-year-old female with no significant comorbidities presented to our care with a penetrating glass injury to her mid-thoracic spine after falling backwards onto a table. A large fragment of glass was protruding from her spine, and multi-planar computed tomography imaging revealed protrusion through the thoracic spinal vertebrae with the glass shards located 2 mm from the aortic lumen. The management of this patient posed several challenges, including initial care of the patient, evaluation of potentially affected structures and the appropriate sequence of therapeutic interventions. After multidisciplinary discussion, our trauma, thoracic and neurosurgical teams formulated a diagnostic workup and two-step surgical approach to address her injuries. Here we present the approach used by our team to successfully manage this type of injury. We hope this case report represents a platform for future discussion on best management approaches in patients presenting with the low-velocity penetrating thoracic, spinal and posterior mediastinal trauma.

Multiplanar evaluation of radiological findings associated with acetabular dysplasia and investigation of its prevalence in an Asian population: a CT-based study

BackgroundAcetabular dysplasia (AD) is a well-known cause of osteoarthritis (OA) of the hip, with its prevalence previously determined on plain radiography. The prevalence of preexisting AD was reported as 7.3% in a patient-based Asian population. Although computed tomography (CT) could evaluate AD in multiple planes, its prevalence using multiplanar CT images has not been reported. We investigated its prevalence with CT on coronal, axial, and sagittal planes and then determined if adding the axial and sagittal planes enhanced the investigation.MethodsWe retrospectively examined 52 consecutive Japanese individuals (mean age 59.4 years) who had undergone CT for conditions unrelated to hip disorders. The inclusion criteria of CT images were (1) reconstructed axial slice thickness of ≤1 mm and (2) normal pelvic rotations and tilt. Exclusion criteria were (1) age <20 years, (2) neither hip center could be clearly detected, (3) evidence of hip OA. The parameters used to define AD on the coronal plane were the center–edge angle, Sharp angle, acetabular index, acetabular depth ratio, and acetabulum head index. The anterior and posterior acetabular sector angles were used as axial parameters and the vertical-center-anterior margin angle as the sagittal parameter. AD prevalence was calculated using multiplanar images and then compared with the previously reported Asian prevalence using 95% confidence intervals (CI). In this study, we defined “prevalence” as the proportion of subjects who had AD in at least one hip.ResultsThe mean prevalence of AD on coronal, axial, and sagittal planes was 16.9, 15.4, and 7.7%, respectively. The lowest prevalence found by combining the three planes was 25.0% (95% CI 15.2–38.2%). This prevalence was significantly higher than that in the previously reported Asian population (7.3%).ConclusionsAt the lowest estimate, the prevalence of AD evaluated in three planes was more than twice as high as the previously reported prevalence in Asians when we investigated its prevalence using multiplanar images. The prevalence of AD in the axial and sagittal planes was not negligible. We therefore suggest that it is important to add axial and sagittal planes’ data when investigating the prevalence of AD.

Vacuum Phenomenon of the Sacroiliac Joint: Correlation with Sacropelvic Morphology.

Study DesignA radiologic study of sacropelvic morphology and vacuum phenomenon of sacroiliac joint in subjects unrelated to low back pain.PurposeThe aim of this study is to describe the relationship between sacropelvic morphology and vacuum phenomenon of the sacroiliac joint.Overview of Literature Lumbopelvic alignment and sacropelvic morphology are associated with the pathomechanisms of various spinal disorders. The vacuum phenomena of the sacroiliac joint (SJVP) are often observed in clinical practice, but the relationships between these phenomena and sacropelvic morphology have not been investigated. This study examined the prevalence of SJVP in computed tomography (CT) images and the relationship between sacropelvic morphology and SJVP.MethodsWe analyzed multiplanar CT images of 93 subjects (59 men, 34 women). Pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), and lumbar lordosis (LL) were measured using the three-dimensional reconstruction method. The prevalence of SJVP in multiplanar CT images were reviewed. Roland-Morris Disability Questionnaire (RDQ) scores and the modified Japanese Orthopedic Association (JOA) score, which focuses on subjective symptoms and restriction of activities of daily living, were also obtained from all the subjects.Results Thirty-six of the 93 subjects had SJVP (39%), with marked female predominance (91% women, 8.5% men). Men with SJVP had significantly lower PI than men without SJVP (35.1° vs. 46.3°, p<0.05). There was no correlation between SJVP and the modified JOA or RDQ scores.ConclusionsThese data suggest that differences in sacropelvic morphology can influence the biomechanical environment and contribute to SJVP in men. Presence of SJVP did not affect JOA or RDQ scores.

Computed Tomographic Evaluation of Degenerative Spine Changes in Patients with Obstructive Sleep Apnea Syndrome: A Case Control Study

Objective: Recently few studies have described presence of cervical spine anomalies in obstructive sleep apnoea syndrome (OSAS) patients. It is also reported that some cases of cervical spine pathologies and osteophytes producing obstructive sleep apnea. We aim to investigate the prevalence of facet joint arthrosis and degenerative disc disease (DDD) in cervical spine using computed tomography (CT) in OSAS patients. Materials and Methods: We studied on thirty patients with OSAS who had cervical spine CT. Facet joints were evaluated in four grades and scored in 1-4 points by using multiplanar CT images. Disc levels was evaluated by using two-point subjective scale for loss of height, posterior osteophytes, endplate sclerosis, and spinal canal stenosis to determinate DDD. Degeneration of anterior atlanto-odontoid joint (AAOJ) were classified into four grades. Tomographic findings were compared with those for thirty control subjects. Results: The mean degeneration scores of C2-T1 facet joints and C2-C5, C7-T1 disc spaces were significantly higher in the cases of OSAS group than the cases of the control group. There were no significant differences in the mean degeneration scores for C5-6 and C6-7 cervical intervertebral disc levels between the groups. Degeneration scores of the facet and disc for whole cervical spine in the cases of the OSAS group was significantly higher than in cases of the control group (P<0.001 and P=0.002). AAOJ degeneration degrees showed differences between the groups. Statistically significant correlations were found between the OSAS degrees and the intervertebral disc degeneration (R=0.338, P=0.007) and facet joint degeneration (R=0.543, P=0.000) for all cervical vertebrae. Conclusions: The cervical spine of the OSAS patients has more severe disc degeneration and facet joint and AAOJ arthrosis, compared to subjects without OSAS. This findings may contribute to clinic evaluation of OSAS patients with servical pain and limited movement.

ETHMOID ROOF RADIOLOGY; AN ANALYSIS OF 110 PATIENTS

We evaluated the extent of asymmetry evident in paranasal sinus computed tomography (CT) scans of Turkish patients without sinusitis in the ethmoid roof. Our data contribute to the body of knowledge on the subject. We retrospectively studied multiplanar reformatted CT images of the paranasal sinus (1-mm sections) from 110 patients (50 male, 60 female). Ethmoid roof variations on either side were compared and the lateral lamellar length of the cribriform plate was measured. The results were scored using the Keros classification. The lateral lamella of the cribriform plate averaged 5.78 mm in height on the right side and 5.98 mm on the left. The most common Keros type was type 2 (67.72%), followed by type 3 (22.28%), and type 1 (10%). Keros asymmetry (≥ 0.01 mm, affecting either side) was apparent in all patients (48.2% right-sided and 51.8% left-sided). Preoperatively, paranasal sinus CT scans should be evaluated carefully to eliminate the possibility of life-threatening complications, including intracranial trauma, which may develop during endoscopic sinus surgery; the left and right sides of the ethmoid roof may differ in depth.

Impact of Starting Point and Bicortical Purchase of C1 Lateral Mass Screws on Atlantoaxial Fusion

Structured review of literature and application of meta-analysis statistical techniques. Review published series describing clinical and radiographic outcomes of patients treated with C1 lateral mass screws (C1LMS), specifically analyzing the impact of starting point and bicortical purchase on successful atlantoaxial arthrodesis. Biomechanical studies suggest posterior arch screws and C1LMS with bicortical purchase are stronger than screws placed within the center of the lateral mass or those with unicortical purchase. Online databases were searched for English-language articles between 1994 and 2012 describing posterior atlantal instrumentation with C1LMS. Thirty-four studies describing 1247 patients having posterior atlantoaxial fusion with C1LMS met inclusion criteria. All studies provided class III evidence. Arthrodesis was quite successful regardless of technique (99.0% overall). Meta-analysis and multivariate regression analyses showed that neither posterior arch starting point nor bicortical screw purchase translated into a higher rate of successful arthrodesis. There were no complications from bicortical screw purchase. The Goel-Harms technique is a very safe and successful technique for achieving atlantoaxial fusion, regardless of minor variations in C1LMS technique. Although biomechanical studies suggest markedly increased rigidity of bicortical and posterior arch C1LMS, the significance of these findings may be minimal in the clinical setting of atlantoaxial fixation and fusion with modern techniques. The decision to use either technique must be made after careful review of the preoperative multiplanar computed tomography imaging, assessment of the unique anatomy of each patient, and the demands of the clinical scenario such as bone quality.

Recent advances in imaging technologies in implant dentistry

Dental implants have become a part of routine treatment plans in oral rehabilitation. Diagnostic imaging is critical to presurgical treatment planning and the success of implants. Various imaging modalities may aid the placing of implants in an appropriate location with relative ease and also obtain a predictable outcome. Cross-sectional imaging techniques such as computed tomography (CT) and, more recently, cone beam-computed tomography (CBCT) are invaluable during preoperative planning for endosseous dental implantation procedures. An understanding of geometric and software parameters, and image formatting options to maximize image display is necessary to optimize diagnostic yield while maintaining minimal patient radiation dose. Multiplanar CT or CBCT images contain far more detailed information of the maxillofacial region than do panoramic or other bidimensional (2D) images and necessitate a thorough knowledge of the tridimensional (3D) anatomy of the region and considerations of variability in the range of the anatomically normal. This article provides: (1) an overview of the fundamental principles of operation of maxillofacial CT and CBCT; (2) an understanding of image processing and display protocols specific to pre-implant bone assessment; (3) the basics of qualitative and quantitative bone evaluation; and (4) an introduction to image-guided implant surgery using custom or computer-generated surgical guides.

Comparison of Axial and Anterior Interbody Fusions of the L5–S1 Segment

Retrospective, multicenter review of 96 patients who underwent L5-S1 interbody fusions through either a standard anterior retroperitoneal approach or using a novel device inserted through the presacral space (AxiaLIF) in conjunction with supplemental posterior fixation between 2002 and 2010. To compare the radiographic fusion rates and adverse events associated with anterior lumbar interbody fusion (ALIF) and AxiaLIF techniques. Interbody fusions of the lumbosacral spine are frequently performed to provide anterior column support, increase the amount of surface area for bone formation, and facilitate deformity reduction. A number of different surgical approaches have been developed for this purpose including minimally invasive techniques. Patient information and procedural data were obtained from hospital charts. Multiplanar computed tomography images were evaluated by 2 independent observers to assess fusion success at 24 months using a 4-point grading scale. In addition to reviewing the medical records to identify any complications, all of the sites were queried regarding any device-related adverse events that may have occurred. According to the radiographic analysis, the arthrodesis rates recorded for the ALIF and AxiaLIF cohorts were 79% and 85%, respectively (P>0.05). The numbers and types of adverse events recorded for these procedures appeared to be similar although there was 1 serious intraoperative complication (iliac artery laceration) noted in the ALIF group. The radiographic success and adverse events associated with AxiaLIF appear to be similar to that observed for ALIF, suggesting that this technique represents a safe and effective method for achieving an interbody fusion across the L5-S1 disk space when utilized in conjunction with posterior fixation.

Computed tomographic anatomy of the nasal cavity, paranasal sinuses and tympanic cavity of the koala

To use cross-sectional imaging (helical computed tomography (CT)) combined with conventional anatomical dissection to define the normal anatomy of the nasal cavity and bony cavitations of the koala skull. Helical CT scans of the heads of nine adult animals were obtained using a multislice scanner acquiring thin slices reconstructed in the transverse, sagittal and dorsal planes. Subsequent anatomical dissection permitted confirmation of correct identification and further delineation of bony and air-filled structures visible in axial and multiplanar reformatted CT images. The nasal cavity was relatively simple, with little scrolling of nasal conchae, but bony cavitations were complex and extensive. A rostral maxillary recess and ventral conchal, caudal maxillary, frontal and sphenoidal paranasal sinuses were identified and characterised. Extensive temporal bone cavitation was shown to be related to a large epitympanic recess. The detailed anatomical data provided are applicable to future functional and comparative anatomical studies, as well as providing a preliminary atlas for clinical investigation of conditions such as cryptococcal rhinosinusitis, a condition more common in the koala than in many other species.

Clinical anatomy of vertebrae in scoliosis: global analysis in four different diseases by multiplanar reconstructive computed tomography

Background contextFew accurate analyses of clinically useful vertebral anatomy have been conducted, and most have focused on thoracic idiopathic scoliosis. PurposeTo evaluate the different anatomic characteristics in scoliosis by disease type and level. Study designObservational cohort study. Patient sampleForty-eight patients with scoliosis were included in this study. Outcome measuresSubjects underwent computed tomography (CT) of the whole spine. MethodsForty-eight patients with scoliosis were included in this study: 15 adolescent idiopathic, 11 cerebral palsy (CP), 10 muscular dystrophy (MD), and 12 congenital (CG) scoliosis patients with similar demographics. Subjects underwent CT of the whole spine, preoperatively. Eight anatomic parameters were measured in multiplanar reconstructive CT images, and statistical analysis was performed to investigate differences. ResultsIn general, values in the anatomic parameters were similar for the four diseases. Each parameter showed the unique change pattern according to the spinal level regardless of curvature shape, direction, or magnitude. In particular, chord length (CL) in MD and CG scoliosis was lower than in adolescent idiopathic scoliosis (AIS) and CP, and pedicle rib unit length was lower in CG scoliosis than in the other diseases (p<.05). Comparisons of convex and concave anatomies in AIS showed that inner pedicle width (PWI) and outer pedicle width (PWO) were wider for convex side, CL, pedicle width, and transverse pedicle angle were greater for concave side (p<.05), and differences were more significant at apices. However, in CP, PWI and PWO were similar between convex and concaves sides (p>.05). Although PWI and PWO were wider for convex sides and CL and pedicle length were greater for concave sides in MD (p<.05), differences were less significant at apices. Particularly, CG scoliosis showed severely deformed anatomy, with differences of seven parameters at apical vertebrae (p<.05). ConclusionClinical anatomies of vertebrae in scoliosis were found to differ significantly at different levels and in terms of convexity and disease type.

MRI can assess glenoid bone loss after shoulder luxation: inter- and intra-individual comparison with CT

Computed tomography (CT) is the gold standard for evaluating glenoid bone loss in patients with glenohumeral dislocations. The aim of this study was to verify if magnetic resonance imaging (MRI) can quantify the area of bone loss without any significant difference from CT. Twenty-three patients, who had experienced one or more post-traumatic unilateral glenohumeral dislocations, underwent MRI and CT. MR and multiplanar reconstruction CT images were acquired in the sagittal plane: the glenoid area and the area of bone loss were calculated using the PICO method. Mean values, percentages, Cohen's kappa coefficients and Bland-Altman plots were all used to confirm the working hypothesis. The mean glenoid surface area was 575.29 mm(2) as measured by MRI, and 573.76 mm(2) as measured by CT; the calculated mean glenoid bone loss was respectively 4.38% and 4.34%. The interobserver agreement was good (k>0.81), and the coefficient of variance was 5% of the mean value using both methods. The two series of measurements were within two standard deviations of each other. MRI is a valid alternative to CT for measuring glenoid bone loss in patients with glenohumeral dislocation.