Cervical Spine CT Using Spectral Shaping: Can It Be a Solution to Overcome Artifacts in the Lower Cervical Spinal Region?

OBJECTIVE: To investigate the image quality, radiation dose, and intermodality agreement of cervical spine CT using spectral shaping at 140 kVp by a tin filter (Sn140-kVp) in comparison with those of conventional CT at 120 kVp. MATERIALS AND METHODS: Patients who had undergone cervical spine CT with Sn140-kVp (n = 58) and conventional 120 kVp (n = 49) were included. Qualitative image quality was analyzed using a 5-point Likert scale. Quantitative image quality was assessed by measuring the noise and attenuation within the central spinal canals at C3/4, C6/7, and C7/T1 levels. Radiation doses received by patients were estimated. The intermodality agreement for disc morphology between CT and MRI was assessed at C3/4, C5/6, C6/7, and C7/T1 levels in 75 patients who had undergone cervical spine MRI as well as CT. RESULTS: Qualitative image quality was significantly superior in Sn140-kVp scans than in the conventional scans (p < 0.001). At C7/T1 level, the noise was significantly lower and the decrease in attenuation was significantly less in Sn140-kVp scans, than in the conventional scans (p < 0.001). Radiation doses were significantly reduced in Sn140-kVp scans by 50% (effective dose: 1.0 ± 0.1 mSv vs. 2.0 ± 0.4 mSv; p < 0.001). Intermodality agreement in the lower cervical spine region tended to be better in Sn140-kVp acquisitions than in the conventional acquisitions. CONCLUSION: Cervical spine CT using Sn140-kVp improves image quality of the lower cervical region without increasing the radiation dose. Thus, this protocol can be helpful to overcome the artifacts in the lower cervical spine CT images.

Simultaneous Estimation of the Fat Fraction and R₂* Via T₂*-Corrected 6-Echo Dixon Volumetric Interpolated Breath-hold Examination Imaging for Osteopenia and Osteoporosis Detection: Correlations with Sex, Age, and Menopause

OBJECTIVE: To investigate the relationships of T2 *-corrected 6-echo Dixon volumetric interpolated breath-hold examination (VIBE) imaging-based fat fraction (FF) and R2 * values with bone mineral density (BMD); determine their associations with sex, age, and menopause; and evaluate the diagnostic performance of the FF and R2 * for predicting osteopenia and osteoporosis. MATERIALS AND METHODS: This study included 153 subjects who had undergone magnetic resonance (MR) imaging, including MR spectroscopy (MRS) and T2 *-corrected 6-echo Dixon VIBE imaging. The FF and R2 * were measured at the L4 vertebra. The male and female groups were divided into two subgroups according to age or menopause. Lin's concordance and Pearson's correlation coefficients, Bland-Altman 95% limits of agreement, and the area under the curve (AUC) were calculated. RESULTS: The correlation between the spectroscopic and 6-echo Dixon VIBE imaging-based FF values was statistically significant for both readers (pc = 0.940 [reader 1], 0.908 [reader 2]; both p < 0.001). A small measurement bias was observed for the MRS-based FF for both readers (mean difference = −0.3% [reader 1], 0.1% [reader 2]). We found a moderate negative correlation between BMD and the FF (r = −0.411 [reader 1], −0.436 [reader 2]; both p <0.001) with younger men and premenopausal women showing higher correlations. R2 * and BMD were more significantly correlated in women than in men, and the highest correlation was observed in postmenopausal women (r = 0.626 [reader 1], 0.644 [reader 2]; both p < 0.001). For predicting osteopenia and osteoporosis, the FF had a higher AUC in men and R2 * had a higher AUC in women. The AUC for predicting osteoporosis was highest with a combination of the FF and R2 * in postmenopausal women (AUC = 0.872 [reader 1], 0.867 [reader 2]; both p < 0.001). CONCLUSION: The FF and R2 * measured using T2 *-corrected 6-echo Dixon VIBE imaging can serve as predictors of osteopenia and osteoporosis. R2 * might be useful for predicting osteoporosis, especially in postmenopausal women.

Ultrasonographic Findings of Subcutaneous Angioleiomyomas in the Extremities Based on Pathologic Subtypes

OBJECTIVE: The purpose of this study was to describe the ultrasonographic findings of angioleiomyoma based on pathological subtypes. MATERIALS AND METHODS: Thirty-nine patients with subcutaneous angioleiomyomas in the extremities were retrospectively reviewed by two radiologists and a pathologist. Sonographic images were analyzed to evaluate each tumor's anatomic location, size, shape, margin, heterogeneity, echogenicity, associated findings, and vascularity. RESULTS: Angioleiomyomas were divided into 3 subtypes: capillary (n = 16), venous (n = 22), and cavernous (n = 1). The one cavernous angioleiomyoma was a hypoechoic mass with rich vascularity. Hypoechogenicity was more frequently observed for venous tumors (77.3%) than for capillary tumors (43.8%), and isoechogenicity was more frequently observed for capillary tumors (56.2%) than for venous tumors (22.7%). Moderate vascularity was more frequently observed for venous tumors (59.1%) than for capillary tumors (12.5%), and little vascularity was more frequently observed for capillary tumors (62.5%) than for venous tumors (13.6%). The aforementioned findings including echogenicity (p = 0.034) and vascularity (p = 0.003) were statistically significant. CONCLUSION: Awareness of sonographic findings of angioleiomyomas based on pathologic subtypes could be helpful for diagnosing angioleiomyoma and could increase diagnostic accuracy for superficial soft-tissue masses in our practice.

Ultrasonography of the ankle joint

Ankle disorders are a relatively common pathological condition, and ankle injuries account for approximately 14% of sports-related orthopedic emergency visits. Various imaging modalities can be used to make a diagnosis in cases of ankle pain; however, ultrasound (US) has several benefits for the evaluation of ankle pain, especially in the tendons, ligaments, and nerves of the ankle. The purpose of this article is to review the common causes of ankle pathology, with particular reference to US features. In addition, the importance of a dynamic evaluation and a stress test with US is emphasized.

Acute Upper Limb Ischemia due to Cardiac Origin Thromboembolism: the Usefulness of Percutaneous Aspiration Thromboembolectomy via a Transbrachial Approach

OBJECTIVE: To evaluate the usefulness of percutaneous aspiration thromboembolectomy (PAT) via a transbrachial approach in patients with acute upper limb ischemia. MATERIALS AND METHODS: From July 2004 to March 2008, eleven patients with acute upper limb ischemia were enrolled in this study. They were initially treated with thrombolysis (n = 1), PAT (n = 6), or both (n = 4) via a femoral artery approach. However, all of the patients had residual thrombus in the brachial artery, which was subsequently managed by PAT via the transbrachial approach for removal of residual emboli. RESULTS: Successful re-canalization after PAT via a transbrachial approach was achieved in all patients. Two patients experienced early complications: one experienced a massive hematoma of the upper arm due to incomplete compression and was treated by stent deployment. The other patient experienced a re-occlusion of the brachial artery the day after the procedure due to excessive manual compression of the puncture site, but did not show recurrence of ischemic symptoms in the artery of the upper arm. Clinical success with complete resolution of ischemic symptoms was achieved in all patients. CONCLUSION: PAT via a transbrachial approach is a safe and effective treatment for patients with acute upper limb ischemia.

Dementia Caused by Post-traumatic Hydrocephalus Showing Marked Improvement After a Shunt Operation

A few cases of dementia caused by posttraumatic hydrocephalus have been reported. A 75-year-old man was admitted to hospital for the evaluation of cognitive impairment and gait disturbance of 2 weeks duration. The patient had been involved in a car accident 50 days prior to his admission. A brain MRI revealed significant hydrocephalus. His score on the Korean version of the Mini Mental State Examination was 14/30, and a neuropsychological assessment revealed severe impairments in all domains. A lumboperitoneal shunt operation was performed. His global cognitive functions and daily activities were fully recovered after the procedure.

Severe Episodic Memory Impairment in a Patient With Clinical Features Compatible With Corticobasal Degeneration

Corticobasal degeneration (CBD) is a progressive neurodegenerative disorder characterized by asymmetric parkinsonism associated with apraxia, cortical sensory loss, and alien-limb phenomenon. Neuropsychological testing in patients with CBD typically shows deficits in executive functions, praxis, language, and visuospatial functioning, but not in memory. We report a CBD patient with severely impaired memory function but relatively mild motor symptoms. Detailed neuropsychological assessment showed significant verbal and visual memory deficits accompanied by frontal executive dysfunctions. Our observations indicate that CBD can in rare cases present with severe episodic memory impairment associated with frontal executive dysfunctions in the early stage of illness.