Comparison of the diagnostic performance of the Swischuk line method and the anterior atlantodental interval method in atlantodental subluxation.

BACKGROUND: Atlantodental subluxation (ADS) is a serious condition that can result in sudden death. Measuring the anterior atlantodental interval (AADI method) is the gold standard for diagnosis but the complex anatomy of this region can make diagnosis difficult, especially for beginners. Therefore, we would like to use a simpler method, the Swischuk line method, to diagnose ADS. The purpose of our study was to evaluate the diagnostic performance of the Swischuk line method for ADS on lateral cervical spine radiographs compared to the AADI method. METHODS: A retrospective study was conducted with patients who presented with ADS (ADS group, n = 32, mean age 57.78 years, age range 34-82 years, 10 men, 21 women) and an age- and sex-matched control group (n = 32). The diagnostic performance of the AADI method and the Swischuk line method for ADS was assessed using lateral cervical radiographs in both flexion and neutral postures by an experienced musculoskeletal radiologist (reader 1), a senior resident (reader 2), and a junior resident (reader 3) in the radiologic department. RESULTS: In the flexion posture, the AADI method and the Swischuk line method showed excellent diagnostic performance with AUCs > 0.9 for readers 1 2 and reader 3. In a neutral posture, the diagnostic performance of the AADI and Swischuk line methods was decreased. With a 1 mm cut-off value using the Swischuk line method in flexion posture, the sensitivity was 75% or more, the specificity was 100%, and the accuracy was 87.50% or more 90.63% for all readers. With a 2 mm cut-off value, the sensitivity was low (37.50-46.88%) but the specificity was 100% for all three readers. In a neutral posture, the sensitivity for both methods decreased, though specificity remained high (> 80%). CONCLUSIONS: The Swischuk line method was found to be reliable and showed high sensitivity and specificity with a cut-off value of 1 mm for the diagnosis of ADS in cervical lateral radiographs in flexion posture. It can be used as a complement to the AADI method.

Increased external rotation of the osteoarthritic knee joint according to the genu varum deformity.

PURPOSE: To evaluate the rotational profile of the lower extremity using computed tomography (CT) in accordance with the degree of varus deformity in medial condyle-affected knee joint osteoarthritis (OA). METHODS: This retrospective study included 1036 patients (872 lower extremities) with end-stage knee OA. The coronal alignment of the lower extremity was measured using standing anteroposterior radiography. The CT parameters of femoral anteversion and tibial torsion were assessed in relation to the knee joint. The axes were the femoral neck axis; the distal femoral axis, which was composed of the anterior trochlear axis, the clinical transepicondylar axis, and the posterior condylar axis; the axis of the proximal tibial condyles; and the bimalleolar axis. RESULTS: There was a tendency for increased external rotation of the knee joint parameters in relation to the hip and ankle joints as varus deformity of the lower extremity increased. The relative external rotational deformity of the knee joint in relation to the hip joint had a positive value with a good correlation. The relative external rotational deformity of the knee joint in relation to the ankle joint also demonstrated a positive value with a good correlation. CONCLUSION: The distal femur and proximal tibia (knee joint) tended to rotate externally in relation to the hip and ankle joint, respectively, as the degree of varus deformity increased. This study identified the relationship between lower extremity varus deformity and rotational deformity of knee joints with OA. LEVEL OF EVIDENCE: III.

Preoperative Shoulder MRI Findings to Predict Subscapularis Tendon Tear Requiring Surgical Repair.

Purpose: This study aimed to investigate which indirect parameters on preoperative MRI were the principal predictors of subscapularis tendon tears (STTs) requiring surgical repair. Materials and Methods: Preoperative MRI scans of 86 patients were retrospectively reviewed for visual assessment of the STT, pathology of the long head of the biceps tendon (LHBT), posterior decentering (PD) of the humeral head, humeral rotation, fatty degeneration, and subscapularis muscle atrophy. To evaluate atrophy, visual grading using the anatomical line connecting the coracoid tip to the glenoid base, designated as the base-to-tip line (BTL), and thickness measurements were performed in the en-face view. Results: Arthroscopically, 31 patients (36%) exhibited Lafosse type III or IV STT and underwent surgical repair. LHBT pathology (p = 0.002), PD of the humeral head (p = 0.012), fatty degeneration (p < 0.001), and BTL grade (p = 0.003) significantly correlated with STT. In the multivariate analysis, PD of the humeral head (p = 0.011, odds ratio [OR] = 5.14) and fatty degeneration (p = 0.046, OR = 2.81) were independent predictors of STT. Conclusion: PD of the humeral head and fatty degeneration of the subscapularis can help to diagnose clinically significant STT. Interpretation of these findings may contribute to the planning of an optimal surgical strategy.

[Detection of Monosodium Urate Crystal of Hand and Wrist in Suspected Gouty Arthritis Patients on Dual-Energy CT and Relationship with Serum Urate Level]. / 손과 손목의 í†µí’ê´€ì ˆì—¼ì—ì„œ 이중에너지 CT를 이용한 요산나트륨 ê²°ì • 검출과 혈중 요산 농도와의 관계.

Purpose: We retrospectively investigated the characteristics of patients with monosodium urate (MSU) deposits of the hand and wrist on dual-energy CT (DECT) compared to those without. We also attempted to determine the pattern of MSU distribution in DECT. Materials and Methods: In total, 93 patients were included who had undergone DECT for evaluation of the hand or wrist pain under the clinical impression of gouty arthritis. The total volume of MSU deposits on DECT was calculated and the pattern of MSU distribution on DECT was analyzed. Also, the level of the serum urate at the time of DECT and the highest level of the serum urate of the patients were obtained from their records and the relationship between MSU and serum urate level was evaluated. Results: The range of the volume of MSU deposits on DECT was 0.01-16.11 cm3 (average: 1.07 cm3). The average level of serum urate was significantly higher in the MSU positive group than that in the MSU negative group. MSU deposits were most frequently observed in the wrists followed by fingers and digitorum tendons. Conclusion: On DECT, MSU deposits were most frequently detected in the wrist and related with high serum urate level.

Multiacquisition with variable resonance image combination T2 (MAVRIC SL T2) for postoperative cervical spine with artificial disc replacement.

Anterior cervical discectomy with artificial disc replacement (ADR) is an effective treatment of cervical degenerative disc disease. However, postoperative MRI due to recurrent neck/radicular pain is limited due to severe metallic artifacts of artificial disc instrument. Multiacquisition with variable resonance image combination selective T2 (MAVRIC SL T2) has been developed as an MRI technique for metal artifact reduction but has not been evaluated for the postoperative cervical spine with ADR. In our study, we compared MAVRIC SL T2 with the fast spin echo (FSE) T2-weighted sequence (T2WI), which was an essential MR sequence for evaluation of the cervical neural structure, for metallic artifact reduction in the post-operative cervical spine with ADR. Our study revealed MAVRIC SL T2 showed smaller signal void areas, less distortion and signal pile-up, and was more clinically useful than T2WI (p < 0.05). The spinal cord, vertebral bodies, both neural foramina, and anterior paravertebral soft tissue were significantly more visible with MAVRIC SL T2 than with T2WI (p < 0.05). MAVRIC SL T2 might be a useful technique for the evaluation of postoperative cervical spine with ADR and complements T2WI in the evaluation of the spinal cord and nerve roots which were important structures for post-operative recurrent neck/radicular pain.

[Pathophysiology and MRI Findings of Infectious Spondylitis and the Differential Diagnosis]. / 감염성 척추염과 감별질환의 병태생리와 MRI 소견.

On MRI, abnormal signals of the intervertebral disc, destruction of the upper and lower vertebral body endplate around the disc, and bone marrow edema around the endplate are considered typical findings of infectious spondylitis. These findings can also appear in various non-infectious spinal diseases, such as degenerative changes, acute Schmorl's node, spondyloarthropathy, synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO), chronic recurrent multifocal osteomyelitis, and calcium pyrophosphate dihydrate crystal deposition disease. The imaging findings of infectious spondylitis that can be differentiated from these non-infectious spinal diseases on MRI are high signal intensity and abscess of the disc space, an abscess in the paraspinal soft tissue, and the loss of the linear low signal intensity on T1-weighted images of the bony endplate. However, these differentiation points do not always apply since there are many similarities in the imaging findings of infectious and non-infectious diseases. Therefore, for an accurate diagnosis, it is important to know the imaging characteristics related to the pathophysiology of not only infectious spondylitis but also non-infectious spinal diseases, which requires differentiation from infection.

Imaging of the seminal vesicle and vas deferens.

The seminal vesicle (SV) and vas deferens (VD) are ancillary but essential urogenital organs. Understanding their embryologic features and anatomy can be helpful in evaluating various disorders of these organs. Recently, cross-sectional imaging modalities, including ultrasonography, computed tomography, and magnetic resonance (MR) imaging, have been increasingly used for evaluation of the SV and VD. The development of these organs is closely related to that of urinary organs, including the kidneys and ureters. Frequently, unilateral SV agenesis is associated with renal agenesis, and bilateral SV or VD agenesis is associated with mutations of the cystic fibrosis gene. Congenital SV cysts are commonly associated with ipsilateral renal agenesis or dysgenesis. These congenital anomalies can be well evaluated with MR imaging. Inflammation, post-radiation therapy changes, and amyloidosis of the SV appear as diffuse wall thickening and may mimic tumor invasion by prostate cancer. Primary neoplasms involving the SV and VD are extremely rare, whereas secondary neoplasms are much more common. Carcinoma from the prostate, bladder, or rectum can directly invade the SV and VD. Typical MR imaging findings of such invasion include a low-signal-intensity mass on T2-weighted images or soft-tissue thickening in the SV or VD along with loss of normal architecture.

Current status of musculoskeletal application of shear wave elastography.

Ultrasonography (US) is a very powerful diagnostic modality for the musculoskeletal system due to the ability to perform real-time dynamic high-resolution examinations with the Doppler technique. In addition to acquiring morphologic data, we can now obtain biomechanical information by quantifying the elasticity of the musculoskeletal structures with US elastography. The earlier diagnosis of degeneration and the ability to perform follow-up evaluations of healing and the effects of treatment are possible. US elastography enables a transition from US-based inspection to US-based palpation in order to diagnose the characteristics of tissue. Shear wave elastography is considered the most suitable type of US elastography for the musculoskeletal system. It is widely used for tendons, ligaments, and muscles. It is important to understand practice guidelines in order to enhance reproducibility. Incorporating viscoelasticity and overcoming inconsistencies among manufacturers are future tasks for improving the capabilities of US elastography.

Comparison of transvaginal ultrasonography with hysterosonography as a screening method in patients with abnormal uterine bleeding.

OBJECTIVE: To assess the utility of hysterosonography (HS) as a screening method in patients with abnormal uterine bleeding. MATERIALS AND METHODS: We retrospectively reviewed transvaginal ultrasonography (TVS) and HS for 105 patients whose diagnosis was confirmed pathologically. All 105 patients were initially evaluated on the same day with both TVS and HS. On TVS and HS examination, endometrial cavitary lesions were classified as diffuse hyperplasia, endometrial polyp, endometrial cancer, uterine synechia and submucosal leiomyoma. Hysteroscopy with biopsy (n=35), curettage (n=60) or hysterectomy (n=10) was performed, and the results of TVS and HS examination were correlated with the pathological findings. RESULTS: The sensitivity and specificity were 79.0% and 45.8% for TVS, and 95.1% and 83.3% for HS, respectively. The positive and negative predictive values were 83.0% and 39.3% for TVS, and 95.1% and 83.3% for HS, respectively. Twenty-seven showed a discrepancy between the TVS and HS, and eight cases showed a discrepancy between HS and the pathologic diagnosis. CONCLUSION: TVS is a sensitive method to evaluate the endometrial cavitary lesions, but it often does not provide the physician with sufficient diagnostic information. With its higher sensitivities, specificities and positive and negative predictive values, HS can be better used than TVS in evaluating those patients with abnormal uterine bleeding.

Ultrasound evaluation of normal and abnormal fetuses: comparison of conventional, tissue harmonic, and pulse-inversion harmonic imaging techniques.

OBJECTIVE: To determine the usefulness of tissue harmonic imaging (THI) and pulse-inversion harmonic imaging (PIHI) in the evaluation of normal and abnormal fetuses. MATERIALS AND METHODS: Forty-one pregnant women who bore a total of 31 normal and ten abnormal fetuses underwent conventional ultrasonography (CUS), and then THI and PIHI. US images of six organ systems, namely the brain, spine, heart, abdomen, extremities and face were compared between the three techniques in terms of overall conspicuity and the definition of borders and internal structures. RESULTS: For the brain, heart, abdomen and face, overall conspicuity at THI and PIHI was significantly better than at CUS (p < 0.05). There was, though, no significant difference between THI and PIHI. Affected organs in abnormal fetuses were more clearly depicted at THI and PIHI than at CUS. CONCLUSION: Both THI and PIHI appear to be superior to CUS for the evaluation of normal or abnormal structures, particularly the brain, heart, abdomen and face.

Radiofrequency ablation of rabbit liver in vivo: effect of the pringle maneuver on pathologic changes in liver surrounding the ablation zone.

OBJECTIVE: We wished to evaluate the effect of the Pringle maneuver (occlusion of both the hepatic artery and portal vein) on the pathologic changes in the hepatic vessels, bile ducts and liver parenchyma surrounding the ablation zone in rabbit livers. MATERIALS AND METHODS: Radiofrequency (RF) ablation zones were created in the livers of 24 rabbits in vivo by using a 50-W, 480-kHz monopolar RF generator and a 15-gauge expandable electrode with four sharp prongs for 7 mins. The tips of the electrodes were placed in the liver parenchyma near the porta hepatis with the distal 1 cm of their prongs deployed. Radiofrequency ablation was performed in the groups with (n=12 rabbits) and without (n=12 rabbits) the Pringle maneuver. Three animals of each group were sacrificed immediately, three days (the acute phase), seven days (the early subacute phase) and two weeks (the late subacute phase) after RF ablation. The ablation zones were excised and serial pathologic changes in the hepatic vessels, bile ducts and liver parenchyma surrounding the ablation zone were evaluated. RESULTS: With the Pringle maneuver, portal vein thrombosis was found in three cases (in the immediate [n=2] and acute phase [n=1]), bile duct dilatation adjacent to the ablation zone was found in one case (in the late subacute phase [n=1]), infarction adjacent to the ablation zone was found in three cases (in the early subacute [n=2] and late subacute [n=1] phases). None of the above changes was found in the livers ablated without the Pringle maneuver. On the microscopic findings, centrilobular congestion, sinusoidal congestion, sinusoidal platelet and neutrophilic adhesion, and hepatocyte vacuolar and ballooning changes in liver ablated with Pringle maneuver showed more significant changes than in those livers ablated without the Pringle maneuver (p < 0.05) CONCLUSION: Radiofrequency ablation with the Pringle maneuver created more severe pathologic changes in the portal vein, bile ducts and liver parenchyma surrounding the ablation zone compared with RF ablation without the Pringle maneuver. Therefore, we suggest that RF ablation with the Pringle maneuver should be performed with great caution in order to avoid unwanted thermal injury.

The effect of zoledronic acid on the volume of the fusion-mass in lumbar spinal fusion.

BACKGROUND: Few studies have explored the effects of bisphosphonates on bony healing in patients undergoing spinal fusion surgery. Most previous studies used animal models and found that bisphosphonate shows negative effects on spinal fusion consolidation. We intended to evaluate the effect of a single-dose of zoledronic acid on the volume of the fusion-mass in lumbar spinal fusion. METHODS: A retrospective review was carried out on 44 patients with symptomatic degenerative lumbar spinal stenosis who underwent one or two-level posterolateral fusion from January 2008 and January 2011. They were divided into 4 groups: group 1, autograft and zoledronic acid; group 2, allograft and zoledronic acid; group 3, autograft alone; and group 4, allograft alone. Functional radiography and three-dimensional computed tomography scans were used to evaluate and quantify the volume of the fusion-mass. The visual analog scale (VAS), the Oswestry disability index (ODI), and the short form 36 (SF-36) were used to evaluate the clinical outcomes. RESULTS: The mean volume of the fusion-mass per level was 8,814 mm(3), 8,035 mm(3), 8,383 mm(3), and 7,550 mm(3) in groups 1, 2, 3, and 4, respectively, but there were no significant differences between the groups (p = 0.829). There were no significant decreases in the volume of the fusion-mass (p = 0.533) in the zoledronic acid groups (groups 1 and 2). The VAS, the ODI, and the SF-36 at the 6-month follow-up after surgery were not significantly different (p > 0.05) among the 4 groups. The VAS, the ODI, and the SF-36 were not correlated with the volume of the fusion-mass (p = 0.120, 0.609, 0.642). CONCLUSIONS: A single dose of zoledronic acid does not decrease the volume of the fusion-mass in patients undergoing spinal fusion with osteoporosis. Therefore, we recommend that zoledronic acid may be used after spinal fusion in osteoporotic patients.

Testicular microlithiasis: clinical significance and review of the literature.

Testicular microlithiasis (TM) is an uncommon condition characterized by calcium deposits within the seminiferous tubules. On ultrasound (US), it is seen as multiple, uniform, nonshadowing echogenic foci in the testis. Although its true prevalence in the general population is still unknown, reported prevalences range from 0.6 to 9%. The TM is often associated with germ cell tumor (GCT) or intratubular germ cell neoplasia. The incidence of GCT in patients with TM was reported as 6-46%. There are several reports demonstrating interval development of GCT in patients with TM. These may suggest a premalignant nature of TM; however, more recent studies show a lower incidence of associated GCT and no interval development of tumor in relatively longer duration follow-up. Additionally, previously reported cases of interval tumor development had predisposing factors for testicular GCT. According to the recent literature, it is suggested that both TM and testicular GCT may be caused by a common defect, such as tubular degeneration, and TM may present as a marker for such abnormalities; however, because of a high incidence of association with GCT, it is prudent to follow up patients with TM with physical examination and US at least annually and to encourage self-examination. The routine use of biochemical tumor markers, abdominal and pelvic CT, or testicular biopsy does not seem to be justified.