Tail Sign Research Articles

MR imaging of myxofibrosarcoma and undifferentiated sarcoma with emphasis on tail sign; diagnostic and prognostic value.

To assess the prevalence of the tail sign in soft tissue sarcomas and determine whether the local recurrence rate differed based on the presence of the tail sign. In our retrospective study, myxofibrosarcoma (MFS, n = 25) and undifferentiated sarcoma (US, n = 38) comprised group 1, and the remaining tumours (n = 115) were assigned to group 2. Location, size, and imaging features of the tumours were assessed on MRI. The radiological-pathological correlation of the tail sign was analysed. The tail sign, thick fascial enhancement extending from the tumour margin, was more common and significantly thicker in group 1. In the subgroup analysis between MFS and US, there was no significant difference in the presence of a tail sign. Histological examination revealed extensive tumour cell infiltrations along the deep fascia from the main mass. Patients with a tail sign had a worse local recurrence-free survival than patients without it, not only in all tumours (p < 0.01), but also in group 1 (p = 0.019) CONCLUSIONS: The tail sign was a common MRI feature of both MFS and US, and was also associated with worse local recurrence-free survival. Radiologists should be aware of these MRI findings and inform the surgeon preoperatively in order to obtain a sufficient surgical margin to minimise the risk of local tumour recurrence. • The tail sign was a common MRI feature of myxofibrosarcoma and undifferentiated sarcoma. • The tail sign may be associated with worse local recurrence-free survival • Radiologists should be aware of this MRI finding and inform the surgeon.

Large capillary hemangioma of the temporal bone with a dural tail sign: A case report.

The present study reports a rare case of large capillary hemangioma of the temporal bone with a dural tail sign. A 57-year-old female presented with pulsatile tinnitus and episodic vertigo associated with a ten-year history of an intermittent faint headache. Magnetic resonance imaging revealed a mass in the right petrous bone, which was hypointense on T1-weighted images and heterogeneously hyperintense on T2-weighted images, and showed a dural tail sign following gadolinium administration. Pre-operatively, this tumor was believed to be a meningioma. During surgery, the vascular tumor was removed by a modified pterional approach. A histopathological examination indicated that the tumor was a capillary hemangioma. Although intraosseous capillary hemangiomas are rare, they most frequently affect the temporal bone. Hemangiomas of the temporal bone may mimic other more common basal tumors. The diagnosis is most often made during surgical resection. The dural tail sign is not specific for meningioma, as it also occurs in other intracranial or extracranial tumors. The treatment of intratemporal hemangiomas is complete surgical excision, with radiotherapy used for unresectable lesions. To the best of our knowledge, the present study is the fourth case of intraosseous intracranial capillary hemangioma, but the largest intratemporal hemangioma to be reported in the literature to date.

Magnetic resonance imaging findings of intracranial papillary meningioma: a study on eight cases

ObjectivesTo increase the awareness on intracranial papillary meningiomas (PMs) by presenting magnetic resonance imaging (MRI) findings on this disease. Materials and methodsThe MRI findings and clinical presentations of nine discrete lesions in eight patients with pathologically documented PMs were retrospectively analyzed. ResultsMost tumors occurred in young adults. The tumors originated from the convexity meninges in five cases and from the parasagittal regions in four cases. The tumor shape was irregular in six cases, lobulated in two cases, and round in one case. By MRI, nine masses were primarily isointense (n=5) or mildly hypointense (n=4) to gray matter on T1-weighted images and inhomogeneous hyperintense (n=3) or isointense (n=6) to the cortex on T2-weighted and fluid-attenuated inversion recovery images. On diffusion-weighted imaging, the signal intensity of the tumor was increased in all lesions compared with the adjacent parenchyma. Tumor and brain interfaces were unclear in seven cases, cyst formation was observed in eight tumors, scattered hemorrhage was observed in three tumors, signal voids due to vessels were visible in four cases, and eight tumors had moderate or marked irregular peritumoral edema. Enhancement was homogeneous (n=2) or heterogeneous (n=7), an area of focal nodular enhancement was observed in three lesions, and the dural tail sign was visible in seven cases. ConclusionAlthough PM is rare, it should be considered in the differential diagnosis when evaluating intracranial neoplasms. Younger patient age, as well as imaging features such as unclear tumor–brain interface, internal heterogeneity including cyst formation, irregular enhancement, signal voids of vessels, and marked peritumoral edema can help distinguish PM from typical benign meningiomas.

Primary extramedullary spinal melanoma mimicking spinal meningioma: A case report and literature review.

Primary spinal melanoma is a rare lesion, which occurs throughout the cranial and spinal regions, however, is primarily observed in the middle or lower thoracic spine. The clinical features of primary spinal melanoma are complex and unspecific, resulting in a high misdiagnosis rate. In the present case report, a rare case of spinal melanoma exhibiting the dural tail sign and mimicking spinal meningioma is reported. The initial diagnosis, using magnetic resonance imaging (MRI), was unclear. Thus, melanin-containing tumors and spinal meningioma should have been considered in the differential diagnosis. The tumor was completely resected using a standard posterior midline approach, which was followed by chemotherapy. Subsequent to the surgery, the patient was discharged with improved motor capacity and a follow-up MRI scan showed no recurrence after six months. The present study demonstrates that it is critical for neurosurgeons to focus on increasing the accuracy of initial diagnoses in order to make informed decisions regarding the requirement for surgical resection. The present case report presents the clinical, radiological and pathological features of primary extramedullary spinal melanoma mimicking spinal meningioma to emphasize the importance of early identification and diagnosis.

Comparison of a new, modified lung ultrasonography technique with high-resolution CT in the diagnosis of the alveolo-interstitial syndrome of systemic scleroderma

Pulmonary fibrosis is the main cause of mortality in patients with Systemic Scleroderma (SSc). This study was performed to investigate the utility of modified trans-thoracic ultrasound (TTUS) scoring system according to the comet tail sign (B-line artifacts) and to compare it with high-resolution computed tomography (HRCT) findings in patients with SSc and pulmonary involvement. Seventy subjects with SSc diagnosed according to the American College of Rheumatology criteria were enrolled. All subjects underwent HRCT followed by TTUS for comet tail sign detection in order to predict the degree of lung fibrosis. The modified TTUS assessment was performed at 10 intercostals spaces level. A significantly positive correlation between TTUS and the severity of pulmonary involvement (Spearman's correlation coefficient= 0.695, P < 0.001), (LR=74.36, P<0.001) was found. When compared with HRCT as the gold standard method, the sensitivity, specificity, positive and negative predictive value of TTUS was 73.58%, 88.23%, 95.12% and 51.72% respectively. Kappa values for the intra-observer modified TTUS assessment was 0.838. Our study showed that the modified TTUS comet tails scoring system could be useful in the assessment of the pulmonary involvement in patients with SSc.

Atoll sign in posterior lenticonus: A case report of bilateral posterior lenticonus with review of literature

Posterior lenticonus is a rare progressive disease characterized by protrusion of posterior lens capsule along with lens cortex into the vitreous cavity. Posterior lenticonus is more common but present unilaterally unlike anterior lenticonus, which presents bilaterally. Posterior lenticonus is a common cause of unilateral infantile cataract but is a very rare cause of bilateral cataract. Diagnosis is mainly clinical but can be difficult in asymptomatic patients; oil drop sign (in mild posterior lenticonus) and fish tail sign (lenticular cortex hanging in vitreous cavity after posterior capsular dehiscence) are described in posterior lenticonus. We are proposing an atoll sign in advanced case of posterior lenticonus with intact posterior capsule on slit lamp examination. The positive atoll sign will have more favorable prognosis since posterior capsule is intact, hence posterior chamber intraocular lens implantation will be more feasible with better visual prognosis as was the case with our patient.

Clinical Features and Surgical Treatment of Aggressive Meningiomas.

To explore the clinical features and surgical treatment of aggressive meningiomas (AMs). Samples from 55 patients with AMs were analyzed, and their clinical characteristics, molecular biological mechanism, and surgical treatment were studied in combination with the literature. The main clinical and imaging features of AMs included manifestations of local structures invaded by tumors, frequently irregular or flat tumors in shape, more obvious cerebral edema surrounding the tumors, seldom calcification of tumor, more frequent and typical dural tail sign, often absent white or black ring sign, partial or complete occlusion of venous sinus and hyperplasia and destruction of local skull. Simpson I resection was achieved in 31 cases, II in 13, III-IV in 11. No severe complications and death occurred after operation. AMs have prominent clinical features. Appropriate surgery can provide a good therapeutic effect.

Factors associated with recurrence of postoperative meningioma: a clinical study of 138 patients

Abstract Background and purpose: As the postoperative recurrence of meningioma can have devastating effects, it is important to identify factors that can be used to predict this type of tumor recurrence. Material and methods: We have performed a retrospective study involving 138 patients who were surgically treated for intracranial meningioma between 2005 and 2010. The patient population consisted of 80 females and 58 males, with an age range of 23 to 77 years old (mean age = 52 years). We measured associations between meningioma recurrence and clinical features (age, sex, extent of resection, histological type), or radiological features (tumor size, location, shape, calcification, bone changes, brain tumor interface, tumor necrosis, and MRI enhancement). Results: We found statistically higher levels of postoperative meningioma recurrence in patients with high Simpson grade resections, high histological types, tumor diameters &gt; 5 cm, tumors located in the base of the skull or the parasagittal sinus, tumors with unclear border, irregular enhancements on MRI, edema around the tumor, bleeding and necrosis within the tumor, and irregularly shaped tumors (e.g., lobulated or mushroom-shaped). In addition, calcification, age, sex, bone change, and dural tail sign provided no predictive value. C onclusions: We have shown that histological type, degree of resection, bleeding, necrosis, edema, irregular enhancement, location, shape, size, and margin serve as strong predictors for the postoperative recurrence of meningioma tumors.

Magnetic Resonance Image Manifestations of the Atypical Meningioma

Through retrospective analysis of 13 cases of magnetic resonance image (MRI) manifestations of atypical meningiomas confirmed by operation and pathology in the First Affiliated Hospital of Xinxiang Medical University, the objective of this study was to evaluate the diagnostic value of MRI in order to improve the accuracy rate of preoperative diagnosis. In this retrospective analysis of MRI findings for atypical meningiomas in First Affiliated Hospital of Xinxiang Medical University from January to July in 2012, the location, morphology and tumor signals and other tumor imaging characteristics were covered. In 13 cases of atypical meningioma patients of this group, most tumors were located at typical sites (10/13), mainly the falx cerebri, parasagittal, convexity, saddle area. Only two cases were at atypical locations, 1 in the cerebellar hemisphere and 1 in a lateral ventricle. Most of the tumors showed T1 and T2 isointensity signals, and necrosis, calcification, and peritumoral edema were always featured. DWI showed isointensity in 11 cases (11/13), and hyperintensity in 2. Some 9 cases had dural tail signs, 12 had accurate positioning (12/13), and 2 were postoperative recurrences. MRI has high value in the diagnosis of atypical meningiomas, with important roles in early clinical diagnosis, treatment and prognosis evaluation.

High frequency ultrasound scan of lower uterine segment during the third trimester of scar uterus pregnancy: imaging features and implications

Objective To use high frequency ultrasound for scanning the lower uterine segment during the third trimester of scar uterus pregnancy,so as to provide reference for selecting the way of delivery.MethodsTotally 118 scar uterus pregnancy cases were selected.Transabdominal ultrasound scan was done for the fetus between 36th and 40th week of pregnancy,and then the transducer was switched to a high frequency of 7.5-12 MHz to observe the lower uterine segment.The scan results were compared with the observations of incomplete rupture of lower uterine segment and defective scars in the repeated caesarean section.ResultsThree types of high frequency ultrasound images were found for the lower uterine segment during the third trimester of scar uterus pregnancy: truncation sign(6.8%,8/118),rat tail sign(44.1%,52/118),and homogeneous echoes(49.1%,58/118). The diagnosis efficacies of truncation sign for incomplete rupture of uterus,rat tail sign for defective scars,and homogeneous echoes for intact caesarean scars were significantly higher than those of the other two types(χ 2 valued 20.42,19.03,and 33.08,respectively,P 0.001).The diagnostic sensitivity,specificity,positive predictive value and negative predictive value of the truncation sign were 80.0%,96.5%,50.0%,and 99.0%;those of the rat tail sign were 70.0%,73.8%,67.3%,and 76.2%;and those of homogeneous echoes were 72.9%,74.6%,74.1%,and 73.3%,respectively.ConclusionHigh frequency ultrasound scan can display the changes of the scars on the lower uterine segment,and may serve as an effective method to diagnose incomplete rupture of uterus,defective and intact scars in the third trimester pregnancy of a caesarean-scarred uterus.To avoid uterine rupture,vaginal trial of labor should be carefully chosen for patients showing truncation sign or rat tail sign.

Achalasia and the rat's tail sign

A 15-year-old young male presented with a progressive of dysphagia for solid and liquid food over a period of 6 months. He denied any drug, foreign body or corrosive ingestion. Physical examination showed non-remarkable findings. Chest radiograph revealed a convex radiopacity overlapped the right heart border …

Multiple cavernous hemangiomas of the skull with dural tail sign: a case report and literature review

BackgroundPrimary intraosseous cavernous hemangioma is a rare bony tumor. To date, only 9 cases of multiple lesions and 2 cases with a dural tail sign have been reported.Case presentationHere, we present a case of multiple cavernous hemangiomas of the skull with dural tail sign in a 24-year-old man. No abnormalities were observed in the right orbit by craniography, but frontal bone destruction was unintentionally discovered. Computed tomography and magnetic resonance imaging demonstrated multiple intraosseous lesions that destroyed the surrounding bone and intracranial extension. Total resection of the two lesions and cranioplasty were performed. Histological examination confirmed the lesions as a cavernous hemangioma.ConclusionCavernous hemangioma is a rare bony tumor that should be considered in the differential diagnosis of skull tumors. Resection of all lesions should be performed on patients with multiple cavernous hemangiomas, and these patients should have regular follow-up examinations. Based on this case, and our literature review, we found that outcomes are usually very good.

Unenhanced CT in the evaluation of renal/ureteric colic

Unenhanced CT of kidneys, ureters and bladder (CTKUB) is now the recommended imaging modality in the investigation of patients with acute renal or ureteric colic. This review aims to illustrate the normal urinary tract anatomy to assist imaging interpretation, outline the CTKUB imaging technique and image review at the Picture Archiving and Communication System workstation, discuss the pertinent imaging findings such as the direct signs, for example, soft tissue rim sign and comet tail sign, as well as secondary indirect signs such as pale kidney sign, nephromegaly, hydronephrosis, hydroureter and perinephric stranding or edema on the CTKUB for the diagnosis. Imaging pitfalls in the interpretation will be illustrated and discussed, for example in the presence of a ureteral stent and optimal image interpretation with wide windowing on CT. In addition, the discussion will also include the use of scout radiograph, the importance of detecting extraurinary pathology during CTKUB examination and explore Randall...

The radiological and histopathological differential diagnosis of chordoid neoplasms in skull base

Background Chordoid neoplasms refer to tumors appearing to have histological features of embryonic notochord, which is characterized by cords and lobules of neoplastic cells arranged within myxoid matrix. Because of radiological and histological similarities with myxoid matrix and overlapping immunohistochemical profile, chordoma, chordoid meningioma, chordoid glioma, and rare extraskeletal myxoid chondrosarcoma enter in the radiological and histological differential diagnosis at the site of skull base. However, there is always a great challenge for histopathologists to make an accurate diagnosis when encountering a chordoid neoplasm within or near the central nervous system. The aim of this study is to investigate and summarize the radiological, histological features and immunohistochemical profiles of chordoid neoplasms in skull base, and to find a judicious panel of immunostains to unquestionably help in diagnostically challenging cases. Methods A total of 23 cases of chordoid neoplasms in skull base, including 10 chordomas, 5 chordoid meningiomas, 3 chordoid gliomas and 5 extraskeletal myxoid chondrosarcomas, were collected from the First Affiliated Hospital, Sun Yat-sen University and Guangdong Tongjiang Hospital. MRI examination was performed on the patients before surgical treatment. Microscopical examination and immunohistochemical staining study using vimentin (Vim), pan-cytokeratin (PCK), epithelial membrane antigen (EMA), S-100 protein (S-100), glial fibrillary acidic protein (GFAP), D2-40, Galectin-3, CD3, CD20, Ki-67 were performed on the samples of cases. The clinicopathological data of the patients was also analyzed retrospectively. Results Most of chordomas were localized in the clivus with heterogeneous hyperintensity on T2WI scanning. The breakage of clivus was observed in most cases. Histologically, the tumor cells of chordoma exhibited bland nuclear features and some contained abundant vacuolated cytoplasm (the so-called physaliferous cells) within myxoid matrix. Areas of cartilage presented in individual cases. The tumor cells of chordoma were diffusely immuno-positive for PCK and EMA. Chordoid meningioma is characterized by a homogeneous contrast-enhancing mass with dural tail sign. The epithelioid cells were arranged in cords and clusters within a myxoid matrix, which was highly reminiscent of chordoma. The ratio of myxoid component and conventional meningioma was different in tumors. EMA was detectable in all chordoid meningiomas, and 4/5 cases were positive for D2-40. That was a finding which was helpful in distinguishing chordoid meningioma from chordoma. Chordoid gliomas were localized in the third ventricle with homogeneous enhancement on MRI examination. The tumors were composed of clusters and cords of epithelioid tumor cells within a variably mucinous stroma containing lymphoplasmacytic infiltratation. The most distinctive immunohistochemical feature of chordoid gliomas is their strong diffuse reactivity for GFAP. EMA and PCK positive expression can also be seen focally in individual cases. Although extraskeletal myxoid chondrosarcomas share the similar radiological and histological appearance with chordoma, all chondrosarcomas in the present study are completely negative for epithelial markers except for immuno-positivity of S-100 focally. In addition, Galectin-3 can be detected in most of chordoid neoplasms in skull base. Conclusion The specific localization and MRI features of tumors are useful diagnostic clues for the differential diagnosis of chordoid neoplasms in skull base. However, combining with histological features, a panel of selected immunostains, including PCK, EMA, GFAP, S-100 and D2-40, is helpful in making an accurate diagnosis for those diagnostically challenging cases which usually appear to have atypical radiological features or in an unusual site. Ki-67 index and Galectin⁃3 are not recommended to use as diagnostic markers for chordoid neoplasms of skull base because of their less neoplastic specificity.

Interobserver agreement and diagnostic accuracy of brain magnetic resonance imaging in dogs

To evaluate interobserver agreement and diagnostic accuracy of brain MRI in dogs. Evaluation study. 44 dogs. 5 board-certified veterinary radiologists with variable MRI experience interpreted transverse T2-weighted (T2w), T2w fluid-attenuated inversion recovery (FLAIR), and T1-weighted-FLAIR; transverse, sagittal, and dorsal T2w; and T1-weighted-FLAIR postcontrast brain sequences (1.5 T). Several imaging parameters were scored, including the following: lesion (present or absent), lesion characteristics (axial localization, mass effect, edema, hemorrhage, and cavitation), contrast enhancement characteristics, and most likely diagnosis (normal, neoplastic, inflammatory, vascular, metabolic or toxic, or other). Magnetic resonance imaging diagnoses were determined initially without patient information and then repeated, providing history and signalment. For all cases and readers, MRI diagnoses were compared with final diagnoses established with results from histologic examination (when available) or with other pertinent clinical data (CSF analysis, clinical response to treatment, or MRI follow-up). Magnetic resonance scores were compared between examiners with κ statistics. Reading agreement was substantial to almost perfect (0.64 < κ < 0.86) when identifying a brain lesion on MRI; fair to moderate (0.14 < κ < 0.60) when interpreting hemorrhage, edema, and pattern of contrast enhancement; fair to substantial (0.22 < κ < 0.74) for dural tail sign and categorization of margins of enhancement; and moderate to substantial (0.40 < κ < 0.78) for axial localization, presence of mass effect, cavitation, intensity, and distribution of enhancement. Interobserver agreement was moderate to substantial for categories of diagnosis (0.56 < κ < 0.69), and agreement with the final diagnosis was substantial regardless of whether patient information was (0.65 < κ < 0.76) or was not (0.65 < κ < 0.68) provided. The present study found that whereas some MRI features such as edema and hemorrhage were interpreted less consistently, radiologists were reasonably constant and accurate when providing diagnoses.

The Striate Artery, Hematoma, and Spot Sign on Coronal Images of Computed Tomography Angiography in Putaminal Intracerebral Hemorrhage

A spot sign is a bright spot on computed tomography angiography source images, which is predictive of hematoma growth in spontaneous intracerebral hemorrhage, although the cause of the spot sign is unclear. Our aim was to investigate the spot sign seen on computed tomography angiography and a striate artery, which is a presumed site of intracerebral hemorrhage bleeding origin in the putamen. In consecutive cases of spontaneous intracerebral hemorrhage in the putamen, spot signs and striate arteries were evaluated. Coronal reformat images of computed tomography angiography were created to visualize the striate arteries. Acute deterioration, defined as hematoma enlargement, emergency hematoma removal, or death within the day of admission, was reviewed. Of the 141 patients undergoing computed tomography angiography, 15 of the 30 patients (50%) who had spot signs showed an intrahematoma striate artery (termed spot and tail sign), which was a linear density extending from the middle cerebral artery toward the spot sign. Acute deterioration occurred more frequently in patients who had a spot and tail sign compared with patients who had spot signs without intrahematoma striate arteries (P<0.05). Multivariate analysis revealed that hematoma volume, spot signs, and intrahematoma striate arteries were independent predictors of acute deterioration (P<0.05). The presence of a spot and tail sign, assumed to indicate active bleeding from the striate artery, could be a more sensitive predictor of acute deterioration than the presence of a simple spot sign.

Achalasia Cardia: Short-term Results of 40 Iraqi Patients

Background: Achalasia is an uncommon but not a rare a malady. In Iraq, we lack true statistics about this condition.&#x0D; Objective: is to review the experience with trans-thoracic modified Heller operation for achalasia cardia in a major thoracic surgical centre in Iraq over a 4-year period.&#x0D; Study design: a combined retrospective and prospective study.&#x0D; Setting: Department of Thoracic Surgery in Baghdad Medical City/Baghdad/Iraq. &#x0D; Methods: This study is both retrospective (20 cases) and prospective (20 cases); the information is collected from either patients, case sheets or obtained directly from patients, interviews. In both situations, relevant demographic and clinical information is obtained. The patients then are subjected to a standard diagnostic workup followed by preparation of patients for surgery. A trans-thoracic modified Heller's operation: esophagocardiomyotomy) is done following a standard technique. No anti-reflux procedure is added. Follow up is done to evaluate results of surgery.Patients: 40 patients (26 males and 14 females) with achalasia cardia who were admitted to the Department of Thoracic Surgery in Baghdad Medical City over a period of 4 years (2008 to 2012).&#x0D; Results: 26 males (65%) and 14 females (35%) with a mean age of 26.6 year. Patients aged 20 -40 years constituted the majority (47.5%). The commonest presenting symptom was dysphagia reported in 39 patients (75%). Cucumber dilated esophagus (rat tail sign) was the commonest appearance on contrast study found in 84% of studied patients. Ten patients (7 females and 3 males) had dilation therapy initially which failed to improve their symptoms thus scheduled for surgery. The remaining 30 patients were offered surgical treatment from the start; thus ultimately, operation was done to all 40 patients. Good to excellent results after surgery were obtained in 35 patients (87.5%).&#x0D; Conclusions: though good and excellent results followed Heller’s operation for achalasia cardia versus multiple forceful dilatations, laparoscopic Heller oesophageal myotomy reverses the symptoms of achalasia with minimal morbidity. It is recommended to learn and practice this minimal invasive procedure rather than to continue doing an old operation.

Study of characteristic differences in CTs and MRIs for intracranial hemangiopericytoma and meningioma to enable better and accurate diagnosis

Objective To study the characteristic differences in CTs and MRIs between intracranial hemangiopericytoma (HPC) and meningioma.Methods 16 cases of HPC and 45 cases of meningioma approved by pathology were selected.All cases underwent MRIs,MR enhancements,DWIs,and CT scans before operation.The MRI and CT finding indexes of tumors between the two groups were analyzed statistically with the x2 test.Results Tumors with lobulated shape (x2 =22.895),necrotic or cystic changes (x2 =15.959),blood vessel flow void phenomenon (x2 =8.058),and obvious enhancements (x2 =7.942) showed remarkably significant statistical differences (P ＜ 0.01) between HPC and meningioma.The skull had no hyperplasia near the tumor (x2 =4.821)and isointense and hypointense signal on DWI (x2 =5.272)showed statistically significant differences (P ＜ 0.05).Dural tail sign (x2 =3.816) and tumor calcification (x2 =0.499) showed no statistically significant differences (P ＞ 0.05).Conclusion There were differences between the CT and MRI findings of HPC and meningioma.It is helpful to improve the level of both CT and MRI diagnosis and clinical diagnosis and treatment through comparative analysis of the findings. Key words: Hemangiopericytoma; Meningioma; CT; MRI; Differential diagnosis

Myxofibrosarcoma: prevalence and diagnostic value of the “tail sign” on magnetic resonance imaging

Myxofibrosarcoma frequently shows curvilinear extensions of high T2 signal that also enhance on magnetic resonance imaging; these "tails" represent fascial extension of tumor at histopathological examination. This study was performed to determine whether the tail sign is helpful in distinguishing myxofibrosarcoma from other myxoid-containing neoplasms. The study group consisted of 44 patients with pathologically proven myxofibrosarcoma; the control group consisted of 52 patients with a variety of other myxoid-predominant tumors. Three musculoskeletal radiologists independently evaluated T2-weighted (and/or short-tau inversion recovery) and post-contrast MR images for the presence of one or more enhancing, high-signal intensity, curvilinear projections from the primary mass. Sensitivity and specificity for the diagnosis of myxofibrosarcoma were calculated for each reader. Interobserver variability was assessed with kappa statistic and percentage agreement. A tail sign was deemed present in 28, 30, and 34 cases of myxofibrosarcoma and in 11, 9, and 5 of the controls for the three readers respectively, yielding a sensitivity of 64-77 % and a specificity of 79-90 %. The interobserver agreement was moderate-to-substantial (kappa=0.626). The tail sign at MRI is a moderately specific and sensitive sign for the diagnosis of myxofibrosarcoma relative to other myxoid-containing tumors.

Ossified thoracic spinal meningioma with hematopoiesis: A case report and review of the literature

Meningiomas account for 25% of spinal tumors, and they are often located in the thoracic spine. The ossified subtype is even rarer, and those with hematopoiesis are rarely described. The mechanism of bone formation has not yet been clarified. A case of ossified spinal meningioma with hematopoiesis occurring in a 78-year-old woman is described. Magnetic resonance imaging revealed a lesion with a dural tail sign at the T9 level located dorsal to the spinal cord. Computerized tomography revealed a high density lesion, as high as the bone signal. Total resection was performed, and the symptoms improved. Pathological findings revealed many psammoma bodies (PBs), bone formation, and bone marrow with hematopoiesis. Both PBs and bone seemed to be based on the same background of calcified structures. This report is the second dealing with ossified spinal meningioma with hematopoiesis. The hardness of the tumor can make the operation more difficult, so that the operation should be performed carefully to avoid injuring the spinal cord.