Oblique Sagittal Images Research Articles

Utility of Oblique Sagittal Reformatted and Three-dimensional Surface Reconstruction Computed Tomography in Foraminal Stenosis Decompression

Determining the responsible level of cervical radiculopathy can be difficult. Because asymptomatic findings are common in cervical radiculopathy, diagnoses based on imaging studies can be inaccurate. Therefore, we investigated whether the application of oblique sagittal reformatted computed tomography (oblique sagittal CT) and three-dimensional surface reconstruction CT (3DCT) affects surgical plans for patients with cervical foraminal stenosis and whether it assists diagnosis of foraminal stenosis. Accordingly, four reviewers, with office notes, observed the CT and magnetic resonance imaging (MRI) images of 18 patients undergoing surgical treatment for cervical radiculopathy. After reviewing the MRI and sagittal, coronal, and axial CT images, the reviewers recorded the operation to be performed; they examined oblique sagittal CT and 3DCT images of the same patients and noted any differences from their surgical plans. Consequently, we analyzed these changes in the decompressed foramina in the surgical plan; mean percent change in the plan was 18.1%. Inter-rater reliability improved from κ - 0.194 to κ - 0.240. Therefore, the addition of oblique and 3DCT images improves inter-rater reliability owing to changes in a part of decompressed foramina. The addition of oblique sagittal CT and 3DCT is helpful in evaluating the foramen and planning surgical treatment of cervical radiculopathy.

Oblique Sagittal Images Prevent Underestimation of the Neuroforaminal Stenosis Grade Caused by Disc Herniation in CervicalSpine MRI.

Purpose To identify whether standard sagittal MRI images result in underestimation of the neuroforaminal stenosis grade compared to oblique sagittal MRI images in patients with cervical spine disc herniation. Materials and Methods 74 patients with a total of 104 cervical disc herniations compromising the corresponding nerve root were evaluated. Neuroforaminal stenosis grades were evaluated in standard and oblique sagittal images by one senior and one resident radiologist experienced in musculoskeletal imaging. Oblique images were angled 30° towards the standard sagittal plane. Neuroforaminal stenosis grades were classified from 0 (no stenosis) to 3 (high grade stenosis). Results Average neuroforaminal stenosis grades of both readers were significantly lower in standard compared to oblique sagittal images (p Conclusion Standard sagittal images tend to underestimate neuroforaminal stenosis grades compared to oblique sagittal images and are less reliable in the evaluation of disc herniations within the cervical spine MRI. In order to assess the potential therapeutic consequence, oblique images should therefore be considered as a valuable adjunct to the standard MRI protocol for patients with a radiculopathy. Key Points Citation Format

Quantification of shoulder muscle intramuscular fatty infiltration on T1-weighted MRI: a viable alternative to the Goutallier classification system.

Quantification of rotator cuff intramuscular fatty infiltration is important for clinical decision-making in patients with rotator cuff tear. The semi-quantitative Goutallier classification system is the most commonly used method, but has limited reliability. Therefore, we sought to test a freely available fuzzy C-means segmentation software program for reliability of the quantification of shoulder intramuscular fatty infiltration on T1-weighted MR images and for correlation with fat fraction by six-point Dixon MRI. We performed a prospective cross-sectional study to measure visible intramuscular fat area percentage on oblique sagittal T1 MR images by fuzzy C-means segmentation and fat fraction maps by six-point Dixon MRI for 42 shoulder muscles. Intra- and inter-observer reliability were determined. Correlative analysis for fuzzy C-means and six-point Dixon intramuscular fatty infiltration measures was also performed. We found that inter-observer reliability for the quantification of visible intramuscular fat area percentage by fuzzy C-means segmentation and fat fraction by six-point Dixon MRI was 0.947 and 0.951 respectively. The intra-observer reliability for the quantification of visible intramuscular fat area percentage by fuzzy C-means segmentation and fat fraction by six-point Dixon MRI was 0.871 and 0.979 respectively. We found a strong correlation between fuzzy C-means segmentation and six-point Dixon techniques; r = 0.850, p < 0.001 by individual muscle; and r = 0.977, p < 0.002 by study subject. Quantification of intramuscular fatty infiltration by fuzzy C-means segmentation on T1-weighted sequences demonstrates excellent reliability and strong correlation with fat fraction by six-point Dixon MRI. Quantitative fuzzy C-means segmentation is a viable alternative to the semi-quantitative Goutallier classification system.

Application of technique of HRCT and multipliate plane reconstruction in analysis of image features of superior semicircular canal dehiscence

Objective: Application of technique of high resolution CT (HRCT) and multipliate plane reconstruction, analyzed the image features of suspicious superior semicircular canal dehiscence (SSCD) to improve the understanding of the SSCD.Method:From January 2016 to April 2017, a total of 230 adult patients who checked temporal bone HRCT were collected in this retrospective study, of which 160 cases (320 ears) of the non-SSCD, 73 cases were male (146 ears), 87 cases were female (174 ears), aged 18 to 70 years old; 70 cases (113 ears) were suspicious diagnosed with SSCD, 33 cases were male (55 ears), 37 cases were female (58 ears), and 18 to 71 years old. The thin section CT scan of the temporal bone translocation was performed on all subjects, then the CT post processing workstation was used for multipliate plane reconstruction (MPR), and the main rows of coronal and oblique sagittal image reconstruction was performed. To observe, measure and record the HRCT features and datas of the suspicious SSCD and non-SSCD, then analyze the collected data.Result:There were 160 cases (320 ears) in non-SSCD group, and the height of the superior semicircular canal was (6.43±0.51)mm, the outer tube diameter was (0.83±0.13)mm, the thickness of the tympanic cavity was (2.19±0.62)mm, the anteroposterior diameter of mastoid was (14.55±1.98)mm; There were 70 cases (113 ears) in the suspicious SSCD group, the above results were (6.42±0.60)mm, (0.85±0.16)mm, (1.62±0.55)mm, (13.24±1.97)mm, respectively. Statistical analysis showed that there were no significant difference in the height of the superior semicircular canal (P=0.94) and the outer tube diameter (P=0.64), There were significant differences in the thickness of the tympanic cavity (P=0.002) and the anteroposterior diameter of mastoid (P=0.004). There were 70 cases (113 ears) in group suspicious SSCD, the unilateral defect had 27 cases (27 ears), and bilateral defect had 43 cases (86 ears). The defect was located in the middle of the parietal wall in 48 ears, located in the anterior wall of 20 ears, located in the posterior wall of 32 ears, more than two defects in 13 ears; 7 ears were mastoid pneumatic type, 90 ears were mastoid sclerotic type, 16 ears were mastoid mixed type.Conclusion:The SSCD was more common in the sclerotic mastoid. The bilateral defect was common, mostly located in the middle of the parietal wall. The occurrence of the lesion is not related to the height and diameter of the superior semicircular canal, but may be related to the thinning of the whole temporal bone.

An MRI evaluation of the effects of qat chewing habit on the temporomandibular joint

The aim of this study was to investigate the effects of the qat chewing habit on the temporomandibular joint by using magnetic resonance imaging. Sixty patients were included: a study group (40 qat chewers) and a control group (20 nonchewers). On the basis of qat chewing habit duration, the study group was subdivided into 3 further subgroups: subgroup I (5-10 years), subgroup II (11-15 years), and subgroup III (>15 years). Data on qat chewing habit were recorded, and a standardized clinical examination was performed. Bilateral oblique sagittal magnetic resonance imaging sections were obtained to evaluate disk displacement, osteoarthritis, and joint effusion. Clicking and pain were diagnosed in 72.5% and 65% of study group patients, respectively. Significant differences were discovered between the study group and the control group in osteoarthritis and joint effusion (P= .003 and .002, respectively). With regard to qat chewing habit duration, there were differences between study subgroup II and subgroup III versus control group in osteoarthritis (P= .040 and .001, respectively) and the 3 study subgroups versus control group in joint effusion (P= .026, .004, and .001, respectively). Significant correlations were found between osteoarthritis and clicking (P= .006) and muscle pain (P ≤ .044), and between joint effusion and temporomandibular joint pain (P = .006) and muscle pain (P ≤ .014). Qat chewing habit may be a risk factor for temporomandibular joint disorders with high percentages of osteoarthritis and joint effusion.

Diagnostic Value of Oblique Coronal and Oblique Sagittal Magnetic Resonance Imaging (MRI) in Diagnosis of Anterior Cruciate Ligament (ACL) Tears.

Introduction: Tears of the anterior cruciate ligament (ACL) are common among young athletes and diagnosis may be difficult especially in the young population. Therefore, finding a new method to increase the correct diagnosis is necessary.Materials and Methods: This double-blind prospective observational study was conducted on 51 patients with suspected ACL rupture. In this study, in addition to the standard protocols, the oblique-sagittal and oblique-coronal MRI were assessed and used in three different methods, including A method (orthogonal MRI protocol), B method (orthogonal MRI protocol and oblique-sagittal MRI), and C method (orthogonal MRI protocol and oblique-coronal MRI).Results: In detecting both complete and partial rupture of ACL, B method had highest diagnostic accuracy (kappa = 0.338, P=0.001), and after that, C method had acceptable accuracy (kappa = 0.292, P=0.011). In addition, in detecting a partial rupture of ACL, B method (kappa = 0.5, P<0.001), and C method had acceptable accuracy (kappa = 0.361, P=0.006). Meanwhile, in detecting a complete rupture of ACL, B method had the highest diagnostic accuracy (kappa = 0.898, P<0.001), and subsequently A method had significant accuracy (kappa = 0.812, P<0.001).Conclusions: Our results showed that the evaluation of ACL rupture by oblique-sagittal MRI in addition to orthogonal MRI protocol is accurate and with high sensitivity and specificity values. It allows to find abnormal images immediately with higher accuracy in the emergency department and more critically ill patients may benefit from the advantages of this imaging protocol.

Can a Single Sagittal Magnetic Resonance Imaging Slice Represent Whole Fatty Infiltration in Chronic Rotator Cuff Tears at the Supraspinatus?

BackgroundThis study aimed to investigate whether fatty infiltration (FI) measured on a single sagittal magnetic resonance imaging (MRI) slice can represent FI of the whole supraspinatus muscle.MethodsThis study retrospectively reviewed the MRIs of 106 patients (age 50–79 years) divided into three rotator cuff tear-size groups: medium, large, and massive. Fat mass and muscle mass on all T1-weighted sagittal MRI scans (FA and MA) were measured. Of the total MRI scans, the Y-view was defined as the most lateral image of the junction of the scapular spine with the scapular body on the oblique sagittal T1-weighted image. Fat mass and muscle mass seen on this Y-view single slice were recorded as F1 and M1, respectively. Fat mass and muscle mass were also assessed on MRI scans lateral and medial to the Y-view. The means of fat mass and muscle mass on these three slices were recorded as F3 and M3, respectively. Average FI ratios (fat mass/muscle mass) of the three assessment methods (F1/M1, FA/MA, and F3/M3) were compared. Intraclass correlation coefficients (ICCs) were calculated for inter- and intraobserver reliability.ResultsICCs showed higher reliability (> 0.8) for all measurements. F1/M1 values were not statistically different from FA/MA and F3/M3 values (p > 0.05), except in males with medium and large tears. F3/M3 and FA/MA were not statistically different. The difference between F1/M1 and FA/MA did not exceed 2%.ConclusionsA single sagittal MRI slice can represent the whole FI in chronic rotator cuff tears, except in some patient groups. We recommend measurement of FI using a single sagittal MRI slice, given the effort required for repeated measurements.

Relationship between the Axillary Nerve and Accompanying Vessels and Proximal Humeral Locking Plates in Japanese: An MRI Study.

We investigated the anatomical features of the axillary nerve and its accompanying vessels with respect to the lateral wall of the greater tuberosity, focusing on the relationship between the neurovascular bundle and the proximal humeral locking plates. Magnetic resonance images of 30 Japanese patients' shoulders were examined. Oblique sagittal images across the greater tuberosity and the neurovascular bundle, which contain the axillary nerve and posterior circumflex humeral artery and vein, were obtained. The distance between the superior aspect of the greater tuberosity and the superior and inferior borders of the neurovascular bundles was measured at the anterior, middle, and posterior edges of the greater tuberosity. The neurovascular bundle was 28.5-36.7 mm, 32.6-41.3 mm, and 38.1-47.5 mm distal to the superior aspect of the greater tuberosity at the anterior, middle, and posterior edges, respectively. We evaluated the relationship between the neurovascular bundle and 3 different locking plates, which were placed at the lateral aspect of the greater tuberosity. Only 3 or four locking screws at the most proximal part could be safely inserted without axillary nerve interference.

Narrowed coraco-humeral distance on MRI: Association with subscapularis tendon tear

PurposeTo highlight the relationship between coraco-humeral distance and subscapularis tendon tear. Material and methodsSixty-two shoulder MRI studies were examined. Twenty-two patients had partial or complete tear of subscapularis tendon and forty shoulder as a control group. Axial and oblique sagittal MR images were examined to measure the coraco-humeral distance followed by statistical analysis to correlate the distance with tendon tear. ResultsA cut-off value of 8.25 mm for the coraco-humeral distance gave a sensitivity of 77.5% and specificity of 72.7% for subscapularis tendon tear. ConclusionThere is a well-known relationship between the coraco-humeral distance and the subscapularis tendon tear and its meticulous assessment in subjects with pain in the anterior shoulder region increases the diagnosis of subcoracoid impingement.

Interreader Reliability and Clinical Validity of a Magnetic Resonance Imaging Grading System for Cervical Foraminal Stenosis

Park system is a magnetic resonance imaging (MRI) grading system for cervical neural foraminal stenosis (CNFS) and consists of 4 grades (0-3) based on the foraminal shape of 45-degree T2-weighted oblique sagittal images. The objective of this study was to evaluate the interreader reliability of the Park system among radiologists, residents, and clinicians. This study also assessed the correlations between radiologic and clinical findings. A total of 289 patients (men:women = 155:134, mean age = 50 years) who underwent oblique sagittal MRI of the cervical spine at our hospital were included. According to the MR grading system suggested by Park et al (Br J Radiol 2013;86:20120515), 2 radiologists, 2 trainees, and 2 clinicians measured CNFS grade at the most narrow point. A neurosurgeon assessed the associated clinical manifestations. κ statistics were used to analyze the interreader agreement among the radiologists and clinicians. The clinical correlations between grade and positive clinical manifestations were assessed with R using nonparametric correlation analysis (Spearman correlation). The overall interreader agreements between radiologists, between trainees, between clinicians, and between radiologists and clinicians were almost perfect (κ = 0.80-0.96). There were moderate correlations between grade and clinical manifestations in each group (R = 0.562-0.669). There were moderate to relatively high correlations between grade and neurologic manifestations based on cervical level (R = 0.570-0.715) (all P < 0.05). Regardless of reader experience, there was substantial to almost perfect interreader reliability with the Park system for CNFS based on oblique sagittal MRI.

Correlation between direction and severity of temporomandibular joint disc displacement and reduction ability during mouth opening.

The most common temporomandibular joint (TMJ) internal derangement is an abnormal relationship of the disc with respect to the mandibular condyle, articular eminence and glenoid fossa-disc displacement. The aim of our study was to analyse the correlation between partial/complete disc displacement in the intercuspal position (IP) and its reduction in the open-mouth position (OMP) in both oblique sagittal and coronal planes on magnetic resonance imaging (MRI) in patients with temporomandibular disorders. Multisection MRI analysis of 382 TMJs was conducted in 191 patients with disc displacement according to the RDC/TMD criteria (148 women, 43 men; aged 14-60years). The disc position was evaluated on all oblique sagittal and coronal images in the IP and the OMP. Univariate logistic regression analysis showed that the severity of disc displacement in the sagittal plane is a statistically significant predictor of reduction ability during mouth opening (B=3.118; P<.001). Moreover, the severity of disc displacement in both planes is also a significant predictor of disc reduction in OMP (B=2.200; P<.05). In conclusion, reduction ability during mouth opening is associated with the severity of disc displacement in IP, in both sagittal and coronal planes. Multisection analysis of all MR images allows distinguishing the correct disc position from disc displacement and can improve the ability to distinguish between various stages of TMJ internal derangement.

Modified Oblique Sagittal Magnetic Resonance Imaging of Rotator Cuff Tears : Comparison with Standard Oblique Sagittal Images

Rotator cuff disease occurs in adults is very common cause of shoulder pain causes is known as one of the. Combined oblique coronal and oblique sagittal standard magnetic resonance (MR) imaging is highly accurate for detecting full-thickness rotator cuff tears. However, the accuracy of standard MR imaging is lower for partial- thickness tears. Small rotator cuff tears can be obscured by partial volume effect if the imaging planes are not orthogonal to the surface of the cuff. Angling the oblique sagittal images perpendicular to the lateral 2 or 3 cm of the supraspinatus tendon would reduce the partial volume effect, and might make tears in this region more conspicuous. The purpose of our study was to compare the accuracy for diagnosing rotator cuff tears of oblique coronal images supplemented with standard oblique sagittal images versus thinner-section modified oblique sagittal fat suppressed fast spin-echo T2-weighted images. For full-thickness supraspinatus tendon tears, our study confirms that oblique coronal and standard oblique sagittal images are very accurate for diagnosing tears, and that supplementing oblique coronal images with thinner-section angled oblique sagittal images does not improve diagnostic accuracy for those few full-thickness tears that are missed on standard MR images. In conclusion, there was a slight improvement in accuracy for diagnosing rotator cuff tears, particularly partial-thickness tears, for the staff radiologist using the thinner-section angled oblique sagittal images.

Instability of the long head of the biceps tendon in patients with rotator cuff tear: evaluation on magnetic resonance arthrography of the shoulder with arthroscopic correlation.

To evaluate the diagnostic value of MR arthrography (MRA) in diagnosing instability of the LHBT in patients with rotator cuff tendon tear. The MR arthrograms of 101 patients were retrospectively reviewed and correlated with arthroscopic findings as the standard reference. Images were evaluated for (1) the integrity of the LHBT, (2) the position of the LHBT (subluxation/dislocation on axial images, inferior displacement on oblique sagittal image) and (3) the integrity of the biceps pulley (SGHL, supraspinatus and subscapularis tendon adjacent to the rotator interval). The integrity of the LHBT was correctly classified in 74.3% (75/101) and 66.3% (67/101) by readers 1 and 2, respectively. The diagnosis of LHBT instability could be made on axial images with a sensitivity of 82.6% and 73.9% and specificity of 69.9% and 87.7%, whereas the displacement sign on sagittal images had a sensitivity of 73.9% and 78.3% and a specificity of 64.4% and 61.6%, respectively. Assessing the integrity of the SGHL had a sensitivity of 60.9 and 93.3% and a specificity of 70.4 and 75.0%, respectively. By combining the different image findings, the accuracy in assessing LHBT instability was 80.9 and 90.5% with a sensitivity of 60.9 and 86.7% and specificity of 83.1 and 91.8%, respectively. Individual image findings may have a limited role in diagnosing LHBT instability in patients with rotator cuff tendon tear. The accuracy of MRA may be improved by assessing the integrity of the biceps pulley structures along with the position of the LHBT on both axial and sagittal images.

A novel diagnostic parameter, foraminal stenotic ratio using three-dimensional magnetic resonance imaging, as a discriminator for surgery in symptomatic lumbar foraminal stenosis

Background ContextNo previous studies have reported the radiological features of patients requiring surgery in symptomatic lumbar foraminal stenosis (LFS). PurposeThis study aims to investigate the diagnostic accuracy of a novel technique, foraminal stenotic ratio (FSR), using three-dimensional magnetic resonance imaging for LFS at L5–S by comparing patients requiring surgery, patients with successful conservative treatment, and asymptomatic patients. Study DesignThis is a retrospective radiological comparative study. Patient SampleWe assessed the magnetic resonance imaging (MRI) results of 84 patients (168 L5–S foramina) aged ≥40 years without L4–L5 lumbar spinal stenosis. The foramina were divided into three groups following standardized treatment: stenosis requiring surgery (20 foramina), stenosis with successful conservative treatment (26 foramina), and asymptomatic stenotic foramen (122 foramina). Outcome MeasuresForaminal stenotic ratio was defined as the ratio of the length of the stenosis to the length of the foramen on the reconstructed oblique coronal image, referring to perineural fat obliterations in whole oblique sagittal images. We also evaluated the foraminal nerve angle and the minimum nerve diameter on reconstructed images, and the Lee classification on conventional T1 images. Materials and MethodsThe differences in each MRI parameter between the groups were investigated. To predict which patients require surgery, receiver operating characteristic (ROC) curves were plotted after calculating the area under the ROC curve. ResultsThe FSR showed a stepwise increase when comparing asymptomatic, conservative, and surgical groups (mean, 8.6%, 38.5%, 54.9%, respectively). Only FSR was significantly different between the surgical and conservative groups (p=.002), whereas all parameters were significantly different comparing the symptomatic and asymptomatic groups. The ROC curve showed that the area under the curve for FSR was 0.742, and the optimal cutoff value for FSR for predicting a surgical requirement in symptomatic patients was 50% (sensitivity, 75%; specificity, 80.7%). ConclusionsThe FSR determined LFS requiring surgery among symptomatic patients, with moderate accuracy. Foramina occupied ≥50% by fat obliteration were likely to fail conservative treatment, with a positive predictive value of 75%.

Comparison of MRI grading for cervical neural foraminal stenosis based on axial and oblique sagittal images: Concordance and reliability study

The aim of this study was to assess the concordance between magnetic resonance imaging (MRI) grading for cervical neural foraminal stenosis (CNFS) based on axial and oblique sagittal images and evaluate the reliability of each grading plane. CNFS was graded at C2–3 to C7–T1 levels based on axial and oblique sagittal images separately by three radiologists. The concordance between CNFS grading based on axial and oblique sagittal images was strong for all three observers (Kendall's W=0.80, 0.79, and 0.82), despite the tendency of higher grading with oblique sagittal images. Both imaging planes supported strong interobserver reliability.

Aortic length measurements for pulse wave velocity calculation: manual 2D vs automated 3D centreline extraction

BackgroundPulse wave velocity (PWV) is a biomarker for the intrinsic stiffness of the aortic wall, and has been shown to be predictive for cardiovascular events. It can be assessed using cardiovascular magnetic resonance (CMR) from the delay between phase-contrast flow waveforms at two or more locations in the aorta, and the distance on CMR images between those locations. This study aimed to investigate the impact of different distance measurement methods on PWV. We present and evaluate an algorithm for automated centreline tracking in 3D images, and compare PWV calculations using distances derived from 3D images to those obtained from a conventional 2D oblique-sagittal image of the aorta.MethodsWe included 35 patients from a twin cohort, and 20 post-coarctation repair patients. Phase-contrast flow was acquired in the ascending, descending and diaphragmatic aorta. A 3D centreline tracking algorithm is presented and evaluated on a subset of 30 subjects, on three CMR sequences: balanced steady-state free precession (SSFP), black-blood double inversion recovery turbo spin echo, and contrast-enhanced CMR angiography. Aortic lengths are subsequently compared between measurements from a 2D oblique-sagittal plane, and a 3D geometry.ResultsThe error in length of automated 3D centreline tracking compared with manual annotations ranged from 2.4 [1.8-4.3] mm (mean [IQR], black-blood) to 6.4 [4.7-8.9] mm (SSFP). The impact on PWV was below 0.5m/s (<5%). Differences between 2D and 3D centreline length were significant for the majority of our experiments (p < 0.05). Individual differences in PWV were larger than 0.5m/s in 15% of all cases (thoracic aorta) and 37% when studying the aortic arch only. Finally, the difference between end-diastolic and end-systolic 2D centreline lengths was statistically significant (p < 0.01), but resulted in small differences in PWV (0.08 [0.04 - 0.10]m/s).ConclusionsAutomatic aortic centreline tracking in three commonly used CMR sequences is possible with good accuracy. The 3D length obtained from such sequences can differ considerably from lengths obtained from a 2D oblique-sagittal plane, depending on aortic curvature, adequate planning of the oblique-sagittal plane, and patient motion between acquisitions. For accurate PWV measurements we recommend using 3D centrelines.

Paper #27 - Correlation of clinical outcomes of retear and tear progression after arthroscopic rotator cuff repair

Background: Rotator cuff retear rate after arthroscopic cuff repair is still high despite advanced arthroscopic techniques and instrument evolution. Even if a retear occurs after rotator cuff repair, improvement in shoulder function is generally maintained, and it is known that rotator cuff integrity does not correlate with clinical outcomes. However, recent studies reported that clinical results of patients with a cuff retear are worse than those with a healed cuff. Therefore, functional outcomes of patients with rotator cuff retear are still on debate. This study evaluated factors related to clinical outcomes of rotator cuff retear after arthroscopic rotator cuff repair focusing on the importance of preoperative and postoperative changes of tear size. Materials and Methods: Four hundred and forty-two patients with full-thickness rotator cuff tear who underwent arthroscopic rotator cuff repair were included in this study. Patients who were possible to cover footprint completely, able to follow up over 2 years, and conducted postoperative MRI at 6 months for tendon integrity were included. The size of tear was measured on the oblique coronal and sagittal images of both preoperative and postoperative MRI. Intact tendon was defined as sufficient thickness of the repaired tendon showing continuity and a homogeneous low-intensity signal in the substance of cuff. Retear was defined as the repaired tendon showing complete discontinuity from footprint. Pain was measured by using VAS score, range of motion was recorded and functional outcomes were measured with ASES and Constant scores. Clinical outcomes were compared between patients with retears and intact cuff. Factors may affect clinical outcome such as preoperative tear size, changes of tear size and retear patterns were evaluated. Results: There were 233 males and 209 females with a mean age of 55 years (range; 46-75 years). Average follow-up period was 33 months (range 24-43 months). Fifty-eight patients (13.1%) had a retear confirmed by postoperative MRI. Patients with a healed cuff showed better shoulder functions than the patients with a retorn cuff (ASES; healed patients, 92.6 ± 9.5 and retear patients, 87.6 ± 12.4, P = .008). 1). Effect of preoperative rotator cuff tear size: In the patients with a preoperative large to massive size, patients with retear showed significant difference in functional outcomes (ASES: 86.5 ± 12.4 and Constant score: 88.7 ± 8.0) when compared with patients with a healed rotator cuff (ASES: 76.9 ± 9.7, P = .02 and 76.9 ± 11.7, P = .001). However, in patients with preoperative small and medium-sized tears, clinical outcomes were not significantly different irrespective of the status of healing of the cuff (ASES: healed cuff, 93.9 ± 7.8 and cuff retear, 93.8 ± 9.2 (P = .37), Constant score: healed cuff, 90.0 ± 11.7 and cuff retear, 91.5 ± 8.5 (P = .47)). 2). Comparative size of retear: Patients with smaller size of retear than the preoperative tear size (n = 28) showed significantly better functional outcomes and muscle strength recovery (Constant score: 90.5 ± 8.8) than those with equal or larger size of retear after surgery (n = 30) (Constant score: 83.7 ± 11.7, P = .025). 3). Retear pattern: Postoperative tear either at the footprint or at the musculotendinous junction did not influence the functional outcomes. 4). Risk factors for retear: Fatty degeneration more than grade 3 (odds ratio = 2.74, (CI: 1.19-6.36), P = .018) and preoperative large to massive rotator cuff tears (odds ratio = 2.2 (CI: 1.17-4.15), P = .015) were preoperatively affecting factors which were significant related to retear after surgery. Age at surgery, sex, symptom duration, arm dominance and associated pathology had no significant effect on the outcome of surgery. Conclusion: Preoperative large to massive rotator cuff tears, and fatty degeneration more than grade 3 are important contributing factors for retear after arthroscopic rotator cuff repair. Patients with preoperative small to medium sized tears had satisfactory clinical outcomes regardless of postoperative tendon integrity. However, in patients with a preoperative large to massive tear who develop retear, the functional outcomes are poorer than patients with a healed cuff. The patients with an equal or larger retorn tendon than preoperative size showed poorer Constant score and muscle strength regardless of preoperative sizes of tear. Therefore, surgeons should take more efforts and employ techniques to reduce the size of retear even if retear occurs.

A 46-Year-Old Woman with Unilateral Hearing Loss: A Recent Diagnosis of a Birth Condition.

Cochlear nerve (CN) aplasia refers to the absence of a visible CN on oblique sagittal magnetic resonance images of the lateral aspect of the inner auditory canal (IAC). Magnetic resonance (MR) is the preferred technique in patients with sensorineural hearing loss and/or vertigo; however, computed tomography (CT) is used to evaluate the IAC or facial nerve canal. Three types of aplasia or hypoplasia can be distinguished (Table 1). A 46-year-old woman came to our ENT consult after being referred for right hearing loss since childhood. There was neither a history of infections nor tinnitus. Otoscopy was normal. Audiometry showed left normoacusia and right profound sensorineural hearing loss. CT scan showed left middle ear normal, with a focal dehiscence in the tympanic portion of the facial nerve, a right middle ear with the ossicles normal, a focal dehiscence in the tympanic portion of the facial nerve and a reduction in the width of the internal auditory canal with normal anterior and posterior labyrinth (Fig. 1). MR was performed to thoroughly evaluate the right inner ear, which confirmed hypoplasia of the cochlear nerve (Figs. 2,3). Cochlear nerve aplasia/hypoplasia can be suspected by CT finding of an internal auditory canal less than 1.5 mm in width because the presence of normal cranial nerves is required for the formation of the IAC and therefore, congenital deficiency of CN VIII (or CN VII) also results in a small or stenotic IAC. It has been reported that IAC stenosis can occur without cochlear nerve hypoplasia; therefore, MR should be performed to detect nerve aplasia or hypoplasia, a challenging diagnosis for the radiologist. In most of the cases, it is associated with profound hearing loss. Nearly all inner ear malformations can be detected on thin-section T2-weighted gradient-echo images or comparable fast spin-echo images. Casselman reported that the cerebellopontine angle should be used as a reference to check the facial and cochlear nerve because he found that the latter was nearly 1 ½-2 times longer than the facial nerve and was never smaller. The nerves are best evaluated and compared on images made perpendicular to the nerves and IAC. This is a case of an adult patient referring to the clinic for right hearing loss since childhood, without ENT evaluation until now. It is important to assess every patient with verified sensorineural hearing loss and no medical history, with radiology tests (CT and MR).

Correlation between the lateral pterygoid muscle attachment type and temporomandibular joint disc position in magnetic resonance imaging.

The aim of this study was to investigate the correlation between the lateral pterygoid muscle (LPM) attachment type and temporomandibular joint (TMJ) disc position on sagittal and coronal MR scans. 191 patients (148 females, 43 males), aged 14-60 years, underwent MR investigations of the TMJs in the intercuspal position (IP) and open-mouth position (OMP). The disc position was evaluated on oblique sagittal and coronal images in the IP and OMP on many MRI sections showing all portions of the joint. Relationships between the LPM attachment patterns and articular disc positions were evaluated by z and χ2 tests. Three types of the LPM attachment were found. There was a statistically significant correlation between the LPM attachment type and the disc position in IP (χ2 = 24.29; p < 0.01). The type of muscle attachment did not determine the prevalence of normal, lateral and medial disc positions. There were differences between the muscle attachment types in the anterior, anteromedial and anterolateral disc positions. There was a statistically significant association between TMJ disc position in OMP and particular attachment types in the sagittal plane (χ2 = 9.702; p < 0.01). Certain types of the LPM insertion are correlated with TMJ disc position.

Efficacy of periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) for shoulder magnetic resonance (MR) imaging

ObjectivesTo elucidate the utility of PROPELLER for motion artefact reduction on shoulder MRI and to examine the influence of streak artefacts on diagnosis of clinical images. Methods15 healthy volunteers and 48 patients underwent shoulder MRI with/without PROPELLER (coronal oblique proton density-fast spin echo [PD-FSE], sagittal oblique T2-FSE). In a volunteer study, all sequences were performed in both static and exercise-loaded conditions. Two radiologists graded artefacts and delineation of various anatomical structures in the volunteer study and motion and streak artefacts in the clinical study. Mean scores were compared between sequences with/without PROPELLER. In the clinical study, mean scores of motion artefacts were compared with mean scores of streak artefacts. Wilcoxon signed-rank test was used for all comparisons. ResultsIn both studies, PROPELLER significantly reduced motion artefacts (P<0.05). In the volunteer study, it significantly improved delineations in sagittal oblique images in the exercise-loaded condition (P<0.05). In the clinical study, streak artefacts appeared dominantly on images with PROPELLER (P<0.05), but influenced diagnosis to a lesser extent than motion artefacts. ConclusionPROPELLER can reduce motion artefacts in shoulder MRI. While it does cause streak artefacts, it affects diagnosis to a lesser extent.