Purpose: We retrospectively evaluated the technical success rate and long-term efficacy of fluoroscopy-guided synovial cyst rupture followed by an intra-articular steroid injection at the post-laminectomy lumbar facet. Materials and Methods: We selected subjects who had undergone a fluoroscopy-guided synovial cyst rupture with simultaneous intra-articular steroid injection within 6 months of MRI and demonstrated a symptomatic facet joint synovial cyst at the level of a previous lumbar laminectomy. Fourteen patients were enrolled, and we determined whether cyst rupture and symptom improvement were achieved after each procedure. The degrees of symptom improvement were categorized into 4: 1) symptoms improved (30% or more reduction, based on pre-procedural and post-procedural Numerical Pain Rating Scale scores), 2) symptoms not improved, 3) patient underwent surgery after injection, and 4) loss of follow-up. Results: The success rate of percutaneous synovial cyst rupture decreased with repeated procedures (62.5% for the first procedure and 0% to 33.3% for additional procedures). However, 80% of the patients had symptom improvement with the procedures, overall. The surgery rate was 14.3% in 14 patients. Conclusion For patients with post-laminectomy symptomatic lumbar facet joint synovial cysts, fluoroscopy-guided synovial cyst rupture with intra-articular steroid injection may be an effective and less invasive treatment before considering a surgical approach.

Purpose: To evaluate the ultrasonographic characteristics of steatocystomas focusing on the features that aid in differentiating them from epidermal inclusion cysts and lipomas. Materials and Methods: The ultrasonographic findings of 14 histologically proven steatocystomas in 10 patients were retrospectively reviewed. The following features were assessed: the layer of involvement, shape, margin, echogenicity, posterior acoustic features, and the presence of a visible wall or intralesional striations. The findings were compared with those of subcutaneous lipomas and epidermal inclusion cysts to identify those findings that aid in the differential diagnosis of steatocystomas. Results: The majority of steatocystomas appeared as a subcutaneous mass (n = 6, 42.9%) or a mass involving both the dermal and subcutaneous layers (n = 6, 42.9%). Steatocystomas exhibited a well-defined smooth margin (n = 12, 85.7%) and homogeneous echogenicity (n = 9, 64.3%), and showed no specific posterior acoustic features (n = 9, 64.3%). The most important features that differentiated steatocystomas from epidermal inclusion cysts were a homogeneous internal echotexture (p = 0.009) and absent or less prominent posterior acoustic enhancement (p < 0.001). The features that distinguished steatocystomas from lipomas were the margin (p < 0.001), echogenicity (p = 0.034), internal echotexture (p = 0.004), and the absence of intralesional striations (p < 0.001). Conclusion Steatocystomas appeared as well-defined homogeneous masses with mild or absent posterior acoustic enhancement.

Hemangioblastomas are low-grade, highly vascular tumors that are usually associated with von Hippel-Lindau syndrome. Hemangioblastomas most commonly occur in the cerebellum, and intradural extramedullary hemangioblastoma of the cauda equina is very rare, especially in patients without von Hippel-Lindau syndrome. Herein, we report a case of intradural extramedullary hemangioblastoma of the cauda equina that was not associated with von HippelLindau syndrome, with a focus on its imaging characteristics and differential diagnoses. We compared the clinical presentation and imaging features of our case with those of previously reported cases in the review of the literature.

Background/Aims: Sacroiliitis is a frequent extraintestinal manifestation of inflammatory bowel diseases (IBDs). This study aimed to assess the prevalence of sacroiliitis using a validated screening tool based on abdominopelvic computed tomography (APCT) in Korean patients with Crohn’s disease (CD) and examine potential associations between clinical characteristics and sacroiliitis. Methods: One hundred five patients with CD undergoing APCT for any indication at an IBD clinic were matched 1:1 for age and sex with 105 controls without underlying chronic illnesses. Using a validated APCT screening tool that defines sacroiliitis as either ankylosis or a total erosion score (TES) ≥ 3, all computed tomography scans were assessed by two independent, blinded radiologists. We compared the prevalence of sacroiliitis between CD patients and controls and clinical characteristics between CD patients with and without sacroiliitis. Results: The prevalence of sacroiliitis was significantly higher in CD patients than in controls (13.3% vs. 4.8%, p = 0.030). All subjects with sacroiliitis had a TES ≥ 3, but no ankylosis. The assessment of sacroiliitis in APCT showed excellent interreader reliability (Cohen’s kappa = 0.933 for presence of sacroiliitis). Sacroiliitis in CD patients was bilateral and asymptomatic. There were no significant associations between sacroiliitis and any demographic data or clinical characteristics in these patients. Conclusions The prevalence of APCT-detected sacroiliitis in CD patients was higher than that in controls, but the condition was asymptomatic. The clinical significance of asymptomatic sacroiliitis in Korean CD patients remains unclear.

Purpose: To evaluate the ultrasonographic characteristics of steatocystomas focusing on the features that aid in differentiating them from epidermal inclusion cysts and lipomas. Materials and Methods: The ultrasonographic findings of 14 histologically proven steatocystomas in 10 patients were retrospectively reviewed. The following features were assessed: the layer of involvement, shape, margin, echogenicity, posterior acoustic features, and the presence of a visible wall or intralesional striations. The findings were compared with those of subcutaneous lipomas and epidermal inclusion cysts to identify those findings that aid in the differential diagnosis of steatocystomas. Results: The majority of steatocystomas appeared as a subcutaneous mass (n = 6, 42.9%) or a mass involving both the dermal and subcutaneous layers (n = 6, 42.9%). Steatocystomas exhibited a well-defined smooth margin (n = 12, 85.7%) and homogeneous echogenicity (n = 9, 64.3%), and showed no specific posterior acoustic features (n = 9, 64.3%). The most important features that differentiated steatocystomas from epidermal inclusion cysts were a homogeneous internal echotexture (p = 0.009) and absent or less prominent posterior acoustic enhancement (p < 0.001). The features that distinguished steatocystomas from lipomas were the margin (p < 0.001), echogenicity (p = 0.034), internal echotexture (p = 0.004), and the absence of intralesional striations (p < 0.001). Conclusion Steatocystomas appeared as well-defined homogeneous masses with mild or absent posterior acoustic enhancement.

Hemangioblastomas are low-grade, highly vascular tumors that are usually associated with von Hippel-Lindau syndrome. Hemangioblastomas most commonly occur in the cerebellum, and intradural extramedullary hemangioblastoma of the cauda equina is very rare, especially in patients without von Hippel-Lindau syndrome. Herein, we report a case of intradural extramedullary hemangioblastoma of the cauda equina that was not associated with von HippelLindau syndrome, with a focus on its imaging characteristics and differential diagnoses. We compared the clinical presentation and imaging features of our case with those of previously reported cases in the review of the literature.

Background/Aims: Sacroiliitis is a frequent extraintestinal manifestation of inflammatory bowel diseases (IBDs). This study aimed to assess the prevalence of sacroiliitis using a validated screening tool based on abdominopelvic computed tomography (APCT) in Korean patients with Crohn’s disease (CD) and examine potential associations between clinical characteristics and sacroiliitis. Methods: One hundred five patients with CD undergoing APCT for any indication at an IBD clinic were matched 1:1 for age and sex with 105 controls without underlying chronic illnesses. Using a validated APCT screening tool that defines sacroiliitis as either ankylosis or a total erosion score (TES) ≥ 3, all computed tomography scans were assessed by two independent, blinded radiologists. We compared the prevalence of sacroiliitis between CD patients and controls and clinical characteristics between CD patients with and without sacroiliitis. Results: The prevalence of sacroiliitis was significantly higher in CD patients than in controls (13.3% vs. 4.8%, p = 0.030). All subjects with sacroiliitis had a TES ≥ 3, but no ankylosis. The assessment of sacroiliitis in APCT showed excellent interreader reliability (Cohen’s kappa = 0.933 for presence of sacroiliitis). Sacroiliitis in CD patients was bilateral and asymptomatic. There were no significant associations between sacroiliitis and any demographic data or clinical characteristics in these patients. Conclusions The prevalence of APCT-detected sacroiliitis in CD patients was higher than that in controls, but the condition was asymptomatic. The clinical significance of asymptomatic sacroiliitis in Korean CD patients remains unclear.

PURPOSE: To describe magnetic resonance imaging (MRI) findings in 10 cases of Toxocara canis myelitis and to analyze these findings to aid in the diagnosis of this condition. MATERIALS AND METHODS: From June 2015 to March 2018, we retrospectively analyzed the electronic medical records and MR images of patients who were diagnosed with Toxocara canis myelitis. The analysis of the MR images was based on a discussion between an experienced spinal radiologist and a radiology resident. RESULTS: This study classified MRI findings into the following two types. Type 1 was defined as central and diffuse T2 high signal intensity on the axial plane, which was observed in 50% of all cases. All lesions showed avid enhancement, mostly in the posterolateral or posterior region (4 cases, 80%). Type 2 was defined as wedge-shaped or focal T2 high signal intensity in the posterolateral or posterior region and corresponded to the remaining 50% of the cases. In this case, the extent of the lesion was relatively small and contrast enhancement was observed in only one case. CONCLUSION This study revealed that various imaging findings could be observed in cases of Toxocara canis myelitis, and the findings were classified into two types.

Hibernoma is a rare benign tumor that arises from vestiges of brown fat. Spinal intraosseous hibernoma has only recently been described in the literature, and only 12 cases have been reported to date due to its extreme rarity. Here, we report the case of a patient who was incidentally diagnosed with an intraosseous hibernoma in the thoracic spine, following a diverse imaging work-up and pathologic confirmation. We correlate the clinical presentation and imaging features of our case with those of previously reported cases during our review of the literature.

Objective: : To evaluate the effectiveness and long-term outcome predictors of percutaneous sacroplasty (PSP). Methods: : This single-center study assessed 40 patients with sacral insufficiency fractures using the short-axis technique under C-arm flat-panel detector computed tomography (CT). Two radiologists reviewed the patients’ magnetic resonance and CT images to obtain imaging findings before PSP and determine technical success, respectively. The short-term outcomes were visual analog scale score changes and opioid usage reductions. Long-term outcomes were determined using telephone interviews and the North American Spine Society (NASS) patient-satisfaction index at least one year after PSP. Results: : Technical success was achieved without any significant complications in 39 patients (97.5%). Telephone interviews were possible with 12 patients and failed in 10 patients; death was confirmed in 18 patients. Fifteen patients (50%) re-visited the hospital and received conservative treatment, including spinal injections. Nine patients reported positive satisfaction (NASS patient-satisfaction index 1 or 2), while the negative satisfaction group (NASS patient-satisfaction index 3 or 4, n=3) showed a higher incidence of compression fractures at the thoracolumbar spine level (66.7% vs. 22.2%) and previous spinal injection history (66.7% vs. 33.3%). The poor response group also showed higher incidences of facet joint arthrosis (100% vs. 55.6%), central canal stenosis (100% vs. 22.2%), neural foraminal stenosis (33.3% vs. 22.2%), scoliosis (100% vs. 33.3%), and sagittal malalignment (100% vs. 44.4%). Conclusion : PSP was effective for sacral insufficiency fractures and showed good long-term outcomes. Combined compression fractures in the thoracolumbar spine and degenerative lumbar pathologies could be possible poor outcome predictors.