Development of a Machine Learning Algorithm to Correlate Lumbar Disc Height on X-rays with Disc Bulging or Herniation.

Lumbar disc bulging or herniation (LDBH) is one of the major causes of spinal stenosis and related nerve compression, and its severity is the major determinant for spine surgery. MRI of the spine is the most important diagnostic tool for evaluating the need for surgical intervention in patients with LDBH. However, MRI utilization is limited by its low accessibility. Spinal X-rays can rapidly provide information on the bony structure of the patient. Our study aimed to identify the factors associated with LDBH, including disc height, and establish a clinical diagnostic tool to support its diagnosis based on lumbar X-ray findings. In this study, a total of 458 patients were used for analysis and 13 clinical and imaging variables were collected. Five machine-learning (ML) methods, including LASSO regression, MARS, decision tree, random forest, and extreme gradient boosting, were applied and integrated to identify important variables for predicting LDBH from lumbar spine X-rays. The results showed L4-5 posterior disc height, age, and L1-2 anterior disc height to be the top predictors, and a decision tree algorithm was constructed to support clinical decision-making. Our study highlights the potential of ML-based decision tools for surgeons and emphasizes the importance of L1-2 disc height in relation to LDBH. Future research will expand on these findings to develop a more comprehensive decision-supporting model.

Update on cerebral hyperperfusion syndrome.

Cerebral hyperperfusion syndrome (CHS) is a clinical syndrome following a revascularization procedure. In the past decade, neurointerventional surgery has become a standard procedure to treat stenotic or occluded cerebral vessels in both acute and chronic settings, as well as endovascular thrombectomy in acute ischemic stroke. This review aims to summarize relevant recent studies regarding the epidemiology, diagnosis, and management of CHS as well as to highlight areas of uncertainty. Extracranial and intracranial cerebrovascular diseases in acute and chronic conditions are considered. The definition and diagnostic criteria of CHS are diverse. Although impaired cerebrovascular autoregulation plays a major role in the pathophysiology of CHS, the underlying mechanism is still not fully understood. Its clinical characteristics vary in different patients. The current findings on clinical and radiological presentation, pathophysiology, incidence, and risk factors are based predominantly on carotid angioplasty and stenting studies. Hemodynamic assessment using imaging modalities is the main form of diagnosis although the criteria are distinct, but it is helpful for patient selection before an elective revascularization procedure is conducted. After endovascular thrombectomy, a diagnosis of CHS is even more complex, and physicians should consider concomitant reperfusion injury. Management and preventative measures, including intensive blood pressure control before, during, and after revascularization procedures and staged angioplasty, are discussed in detail.

A Case of Occlusive Radiation Vasculopathy Presenting as Bilateral Internal Carotid Artery, Left Middle Cerebral Artery Occlusion and Literature Review.

Radiation vasculopathy is one of the rare causes of ischemic stroke. Carotid stenosis with large volume infarction may occur years after radiation therapy for head or neck cancer. We report a case of a patient with bilateral internal carotid artery occlusion presenting with left middle cerebral artery infarct 10 years after receiving treatment for tongue cancer. A literature review and discussion of treatment for such patients are presented.

Volume Visualization for Improving CT Lung Nodule Detection.

Inspired by the outstanding performance of deep convolutional neural networks (CNNs), nowadays modern computer-aided detection (CAD) systems for CT lung nodules generally delve into 2D or 3D CNNs directly without considering traditional image preprocessing techniques. However, detection of large pulmonary nodules and masses are computationally challenging, especially for 3D CNNs. In this paper, we examine the possibility of using volume visualized CT thin-slab images with 2D CNNs to reduce computation complexity and improve CAD performance. We tested 4 types of images: original 2D CT, 2D projection of thin slabs, mixture by arranging original and projection in different color channels, and mixture by the pixelwise maximum intensity of original CT and projection. We evaluated these images on a dataset of 30 CT scans with 30 different-sized nodules and masses on GoogLeNet via a transfer learning and cross validation paradigm. We found that projection visualization alone had a better or equal area-under curve score for all the different-sized nodules and masses. However, mixture by the maximum of CT and projection demonstrated a preferred performance with a true positive rate of 0.8 and a false positive rate of 0.046 in detecting large nodules and masses.

Greater ultrasonographic changes in pediatric moyamoya patients compared with adults after indirect revascularization surgeries.

OBJECTIVEPediatric and adult patients with moyamoya disease experience similar clinical benefits from indirect revascularization surgeries, but there are still debates about age-related angiographic differences of the collaterals established after surgery. The goal of this study was to assess age-related differences on ultrasonography before and after indirect revascularization surgeries in moyamoya patients, focusing on some ultrasonographic parameters known to be correlated with the collaterals supplied by the external carotid artery (ECA).METHODSThe authors prospectively included moyamoya patients (50 and 26 hemispheres in pediatric and adult patients, respectively) who would undergo indirect revascularization surgery. Before surgery and at 1, 3, and 6 months after surgery, the patients underwent ultrasonographic examinations. The ultrasonographic parameters included peak-systolic velocity (PSV), end-diastolic velocity (EDV), resistance index (RI), and flow volume (FV) measured in the ECA, superficial temporal artery (STA), and internal carotid artery on the operated side. The mean values, absolute changes, and percentage changes of these parameters were compared between the pediatric and adult patients. Logistic regression analysis was used to clarify the determinants affecting postoperative EDV changes in the STA.RESULTSBefore surgery, the adult patients had mean higher EDV and lower RI in the STA and ECA than the pediatric group (all p < 0.05). After surgery, the pediatric patients had greater changes (absolute and percentage changes) in the PSV, EDV, RI, and FV in the STA and ECA (all p < 0.05). The factors affecting postoperative EDV changes in the STA at 6 months were age (p = 0.006) and size of the revascularization area (i.e., revascularization in more than the temporal region vs within the temporal region; p = 0.009). Pediatric patients who received revascularization procedures in more than the temporal region had higher velocities (PSV and EDV) in the STA than those who received revascularization within the temporal region (p < 0.05 at 1-6 months), but such differences were not observed in the adult group.CONCLUSIONSThe greater changes of these parameters in the STA and ECA in pediatric patients than in adults after indirect revascularization surgeries indicated that pediatric patients might have a greater increase of collaterals postoperatively than adults. Pediatric patients who undergo revascularization in more than the temporal region might have more collaterals than those who undergo revascularization within the temporal region.

Improving Indirect Revascularization for Effective Treatment of Adult Moyamoya Disease: A Prospective Clinical, Cerebral Angiographic, and Perfusion Study.

BACKGROUND: Indirect revascularization is simple and safe, but it is not commonly used in adult moyamoya disease owing to its unreliable effect. This prospective study aimed to evaluate the effectiveness of indirect revascularization in treating adult moyamoya disease after refinement of the surgical technique and perioperative care. METHODS: Adult patients who underwent indirect revascularization as the primary treatment for moyamoya disease between November 2013 and January 2017 were studied. The indirect revascularization procedures included encephalo-duro-arterio-synangiosis and encephalo-myo-synangiosis in the temporal region and encephalo-pericranio-synangiosis in other hypoperfusion areas. The preoperative and postoperative clinical conditions, cerebral angiography findings, and time-to-peak prolongation areas on magnetic resonance perfusion studies were assessed to evaluate the revascularization effect. Refinements of the surgical technique included the selection of surgical area based on perfusion imaging, craniotomy size, and number of affected hemispheres, along with the inclusion of a dural flap in every procedure. RESULTS: Nineteen patients (17 females and 2 males), and a total of 31 cerebral hemispheres, were included. The mean patient age was 32.7 ± 11.4 years. After a mean follow-up of 38.6 ± 11.5 months, all patients showed clinical improvement or stabilization. Available postoperative angiography demonstrated Matsushima grade A or B in 19 of 21 hemispheres. The mean time-to-peak prolongation index of all 31 hemispheres improved from 24.09 ± 9.83% preoperatively to 12.82 ± 6.75% at 3-6 months after surgery (P < 0.001). The complication rate was 12.9%, and all complications were transient. CONCLUSIONS: With refinements of surgical techniques and perioperative care, indirect revascularization is more reliable and can be a viable alternative treatment for adult moyamoya disease. In our cohort, outcomes were satisfactory, with mean 38.6-month follow-up.

Engorged medullary vein on CT angiography in patients with dural arteriovenous fistula: prevalence, types, and comparison between regional and extensive types.

BACKGROUND AND PURPOSE: Engorged medullary vein (EMV) in patients with intracranial dural arteriovenous fistula (DAVF) suggests venous congestion. The aim of this study is to investigate its prevalence, pattern, and correlation with clinical findings. MATERIALS AND METHODS: CT angiography (CTA) raw data of DAVF were used for multiplanar reconstruction and then analyzed for the presence and pattern of EMV, which is defined as a dilated vein in the cerebral white matter. Patients with EMV were divided into two groups: regional and extensive. Regional type is defined as EMV limited to one cerebral hemisphere or cerebellum without evidence of subcortical calcification. Extensive type is defined as EMV involvement of more than one cerebral hemisphere or both the cerebrum and cerebellum. Descriptive analysis of clinical information, DAVF characteristics, and other imaging findings was conducted. Clinical information, including demographic data, clinical presentation, and hemorrhage, were correlated with both types of EMV. RESULTS: Among 192 eligible patients with DAVF, 71 (37%) had EMV. Patients with EMV were older (63 years vs 56 years, P=0.02), with DAVF more often at the transverse and sigmoid sinus (P<0.001), and more often presented with aggressive symptoms (59% vs 34%, P=0.02) than non-EMV patients, but there was no difference in the presentation of hemorrhage (15% vs 16%, P=0.99). Patients with regional EMV had a higher proportion of hemorrhage than those with the extensive type (24% vs 0%, P=0.006). CONCLUSIONS: EMV in patients with DAVF is associated with an aggressive manifestation. Regional type EMV is associated with a higher risk of a hemorrhagic presentation.

Organic anion-transporting polypeptide 1B3 as a dual reporter gene for fluorescence and magnetic resonance imaging.

Reporter proteins have broad applications in visualizing molecular events at the cellular, tissue and whole-body levels. Transmembrane transporters recognizing specific molecular domains are of particular interest because they enable the migration of signal-source molecules from the extracellular space to the cytoplasm for subsequent application in multimodality imaging. Organic anion-transporting polypeptides (OATPs) have demonstrated their MRI reporter efficacy. We further expanded their use as a dual-modality reporter in MRI and noninvasive in vivo imaging system (IVIS). We overexpressed OATP1B3 in the HT-1080 sarcoma cell line. Both Gd-EOB-DTPA, an MRI contrast agent, and indocyanine green (ICG), a near-infrared fluorescent dye that provides better deep-tissue detection because of its long wavelength, could be delivered to the intracellular space and imaged in a tumor-bearing nude mouse model. Our in vivo dual-imaging reporter system achieved high sensitivity in MRI and observation periods lasting as long as 96 h in IVIS. Because of the superior temporal and spatial resolutions and the clinical availability of both ICG and Gd-EOB-DTPA, this dual-imaging OATP1B3 system will find biomedical use in tumor biology, stem cell trafficking, and tissue engineering.-Wu, M.-R., Liu, H.-M., Lu, C.-W., Shen, W.-H., Lin, I.-J., Liao, L.-W., Huang, Y.-Y., Shieh, M.-J., Hsiao, J.-K. Organic anion-transporting polypeptide 1B3 as a dual reporter gene for fluorescence and magnetic resonance imaging.

Color Doppler ultrasonography as an alternative tool for postoperative evaluation of collaterals after indirect revascularization surgery in Moyamoya disease.

The cerebral hypoperfusion caused by chronic progressive stenosis or occlusion of intracranial arteries in moyamoya disease can be treated by direct bypass or indirect revascularization procedures. The extent of collaterals from the external carotid artery (ECA) after indirect revascularization surgery is the key point of angiographic follow-up, and the invasiveness of angiography impelled us to investigate the role of ultrasonography in the evaluation of collaterals. We hypothesized that the collaterals shown on angiography might produce corresponding hemodynamic changes in color Doppler ultrasonography. We prospectively recruited moyamoya patients who underwent indirect revascularization surgery and received both preoperative and postoperative angiography and color Doppler ultrasound studies. The collaterals on angiography were graded according to Matsushima method. A total of 21 patients (age, 17 ± 10.2 years) with 24 operated hemispheres were enrolled. Patients who showed better collateral establishment by angiography had higher end-diastolic velocity (EDV), lower resistance index (RI), and larger flow volume in the superficial temporal artery (STA) and ECA (all p < 0.05). In STA, increase of EDV greater than 13.5 cm/sec or reduction of RI greater than 0.19 after operation corresponded to 94% of Matsushima grade A+B. In ECA, post-operative EDV greater than 22 cm/sec or increase of EDV greater than 6.4 cm/sec also corresponded to 94% of Matsushima grade A+B. Our findings revealed potential roles of color Doppler ultrasonography in identifying patients with poor collaterals after indirect revascularization procedures.

Characterization of an iron oxide nanoparticle labelling and MRI-based protocol for inducing human mesenchymal stem cells into neural-like cells.

The aim of the current study was to develop an iron oxide nanoparticle (ION) labelling and magnetic resonance imaging (MRI)-based protocol to allow visualization of the differentiation process of mesenchymal stem cells (MSCs) into neural-like cells (NCs) in vitro. Ferucarbotran, a clinically available ION, which can be visualized under MRI, is used for tracking cells implanted in vivo. The NCs were verified morphologically and histologically by light microscopy, and their functions were verified by measuring their action potentials. Conformational conversion of axon-like structures was observed under light microscopy. These NCs exhibited frequent, active action potentials compared with cells that did not undergo neural differentiation. The labelling of ION had no influence on the morphological and functional differentiation capacity of the MSCs. We conclude that the MSCs that were differentiated into NCs exhibited in vitro activity potential firing and may be used to replace damaged neurons.

Ultrasonographic Changes after Indirect Revascularization Surgery in Pediatric Patients with Moyamoya Disease.

The marked cerebral hypoperfusion of moyamoya disease (MMD) can be treated with encephaloduroarteriosynangiosis (EDAS), an indirect revascularization surgery. Collateral establishment after the surgery is a gradual process; thus, easy access to serial assessment is of great importance. We prospectively recruited 15 pediatric moyamoya patients who underwent EDAS surgeries on a total of 19 hemispheres. Ultrasonography of extracranial and intracranial arteries was performed pre-operatively and post-operatively at 1, 3 and 6 mo. Among the extracranial arteries, the superficial temporal artery had the most pronounced increase in flow velocity and decrease in flow resistance from 1 mo post-surgery (p < 0.01). Among the large intracranial arteries, a significant increase in peak systolic velocity was observed in the anterior cerebral artery from 3 mo post-surgery (p < 0.05). These findings indicate significant hemodynamic changes on ultrasonography in pediatric moyamoya patients after indirect revascularization surgery.

Diagnosis and management of intracranial dural arteriovenous fistulas.

Dural arteriovenous fistula (DAVF) is a rare type of acquired intracranial vascular malformation. Recent progress in neuroimaging technology, such as advanced MRI and CT, provides non-invasive methods to accurately diagnose DAVF, including evaluation of the hemodynamics of the drainage veins. The clinical manifestations of DAVFs vary widely and depend on the location and venous drainage pattern of arteriovenous shunting. Patients with high grade DAVFs having cortical venous reflux should receive aggressive treatment to prevent the occurrence of intracranial hemorrhage and other neurological deficits related to venous congestion. Intra-arterial or intravenous endovascular embolization remains the primary therapy for high grade DAVF, while open surgery and stereotactic radiosurgery can serve as alternative treatment options. Early and accurate diagnosis with appropriate treatment is the goal for clinical management of DAVFs to reduce symptoms and prevent the development of venous congestion and stroke.

Validity of Carotid Duplex Sonography in Screening for Intracranial Dural Arteriovenous Fistula among Patients with Pulsatile Tinnitus.

Pulsatile tinnitus may result from intracranial dural arteriovenous fistula (DAVF), which requires early diagnosis and management. This study validated the role of carotid duplex sonography in screening for DAVF in patients with pulsatile tinnitus. The criteria used for DAVF screening were low resistance index of the external carotid artery or occipital artery (OA). Patients then underwent head magnetic resonance imaging to confirm the diagnosis. Of the 155 patients with pulsatile tinnitus who were prospectively screened, 25 (16.1%) had a low resistance index in either the external carotid artery or occipital artery. All were proven to have DAVF. The diagnostic sensitivity, specificity, positive predictive value and negative predictive value were 96%, 100%, 100% and 98%, respectively. Thus, carotid duplex sonography focusing on low resistance indexes of the external carotid and occipital arteries may be a valuable tool in screening for DAVF in patients with pulsatile tinnitus.

Prioritized Venous Coiling Facilitating Endovascular Treatment of Brain Arteriovenous Malformations with a Fistulous Component.

BACKGROUND: Brain arteriovenous malformation (AVM) with a fistulous component presents a treatment challenge. The presence of the fistulous component may be related to either a complication from endovascular treatment, perioperative hemorrhagic events during surgical resection, or incomplete obliteration after radiosurgery. CASE DESCRIPTION: From December 2010 to May 2014, 7 consecutive patients (3 men, 4 women, average age, 28.7 years; age range, 11 months to 67 years) with AVMs with a high-flow fistulous component were treated at our institute with venous coiling before transarterial liquid embolization. One AVM was grade I based on the Spetzler-Martin grading system, 1 was grade II, 3 were grade III, and 2 were grade IV. The nidus size ranged from 1.7 to 6.0 cm. Four patients had pure fistulous-type lesions, and 3 had lesions of the mixed fistulous-plexiform type. All AVMs shared a common feature of a high-flow fistulous component with a large venous pouch emerging from the nidus. After endovascular embolization of the AVMs, 3 patients had complete occlusion, 3 patients had near-complete occlusion, and 1 patient had significant reduction in volume. There was no immediate complication after embolization, but 1 patient experienced delayed hemorrhage 3 days after the procedure. CONCLUSIONS: Prioritized transarterial venous coiling is feasible for the embolization of AVMs with a high-flow fistulous component and the procedure had an acceptable complication rate.

A multifunctional peptide for targeted imaging and chemotherapy for nasopharyngeal and breast cancers.

The L-peptide plays a role as a universal ligand binding specifically to nasopharyngeal carcinoma (NPC) and other cancers but not normal cells. It was used to link iron oxide nanoparticles, and injected intravenously to SCID mice bearing NPC and breast cancer xenografts for MR analysis, and showed significant change of MR signal intensity in the xenograft regions. Using this conjugate as a ligand to localize the L-peptide targeted protein in the cancer surgical specimens, a clear reaction product was identified in the tumor cells of both cancer types. If the L-peptide-linked-liposomal doxorubicin was used to treat the SCID mice bearing other NPC or breast cancer xenograft, a high efficacy of chemotherapy with minimal adverse effect was observed. In conclusion, the L-peptide has a considerable potential for clinical usage for targeted imaging, peptide histochemical localization of targeted protein, and targeted chemotherapy for different cancer types. FROM THE CLINICAL EDITOR: Targeted chemotherapy to cancer cells will enable maximum drug delivery but minimal systemic side effects. In this article, the authors identified a protein, L-peptide, on tumor cells. They also subsequently confirmed the specificity of this protein in animal experiments using iron oxide nanoparticles. The discovery of this marker could lead to future development of better chemotherapy.

Magnetic resonance imaging following endoscopic nasopharyngectomy with a potassium-titanyl-phosphate (KTP) laser for early locally recurrent nasopharyngeal carcinoma.

INTRODUCTION: This study aims to investigate the spectrum of magnetic resonance imaging (MRI) features following endoscopic potassium-titanyl-phosphate (KTP) laser nasopharyngectomy. METHODS: From January 2005 to December 2010, a total of 35 patients underwent KTP laser nasopharyngectomy for early recurrent NPC (rT1 or rT2) at our institute. Those who were lost to follow-up (N = 2) were excluded. Among the remaining patients, ten were proved to have locally recurrent disease and the other 23 not locally recurrent within 2 years of postoperative follow-up. Their serial MRIs were evaluated. RESULTS: Postoperative nasopharyngeal mucosal changes were present in all of the subjects on first follow-up MRI, ranged from focal mucosal thinning (19/33, 57.6 %), focal mucosal thickening (8/33, 24.2 %) to mixed thinning and thickening (6/33, 18.2 %). Nasopharyngeal submucosal soft tissue volume loss was found in 23 (23/33, 69.7 %), and parapharyngeal soft tissue necrosis was found in 3 (3/33, 9.1 %). Postoperative bone marrow change involved the clivus in 31 (31/33, 93.9 %) and the petrous or pterygoid in 17 (17/33, 51.5 %). There were no significant differences between the two groups in the changes of mucosa, adjacent soft tissue, and skull base on the first MRI. The evaluation of serial MRIs disclosed that the patients in the recurrent group were more likely to develop new or enlarging mucosal masses (p = 0.01) and enlarging skull base changes (p = 0.0001). CONCLUSIONS: KTP laser nasopharyngectomy induces mucosal and skull base changes that could be misinterpreted as tumor progression on early postoperative MRI scans. Sequential imaging is required to distinguish between postoperative changes and progressive disease.

Clinical characteristics of central diabetes insipidus in Taiwanese children.

BACKGROUND/PURPOSE: Data on the clinical features of children with central diabetes insipidus (CDI) are lacking in Taiwan. This study investigated the clinical manifestations and etiology of CDI in Taiwanese children. METHODS: From 1983 to 2012, 62 children with permanent diabetes insipidus were enrolled in the study. They were diagnosed at the Department of Pediatrics of National Taiwan University Hospital. Their medical records were thoroughly reviewed and their clinical symptoms and signs, laboratory data, and etiologies were analyzed. RESULTS: The patients' median age at diagnosis was 10 years and the median interval between initial manifestations and diagnosis was 0.5 years. The most common symptoms and signs were polyuria, polydipsia, nocturia, and growth retardation. Most patients had low urine osmolality and elevated plasma osmolality on diagnosis. Absence of a posterior pituitary hyperintense signal and thickening of the pituitary stalk were common findings on magnetic resonance imaging. Approximately 80% of the patients had anterior pituitary hormone deficiency and all patients had growth hormone deficiency. Approximately 60% of patients had intracranial lesions, the most common causes of which were germ cell tumor and Langerhans cell histiocytosis. Two patients were initially believed to have idiopathic CDI but intracranial lesions were detected during the follow-up period. CONCLUSION: Because a delayed diagnosis of CDI is common in Taiwanese children, a high index of suspicion is important. The underlying etiology of CDI in children may not initially be obvious. Long-term surveillance is therefore necessary, especially for the early detection of evolving treatable intracranial lesions.

Rapid, sequential bilateral acute carotid blowout syndrome.

INTRODUCTION: This study aims to report the treatment and outcome of sequential bilateral acute carotid artery blowout syndrome. METHODS: From 2004 to 2010, we treated seven male patients with sequential bilateral blowout syndrome long after irradiation treatment for head and neck cancer. After first common carotid artery (CCA)-internal carotid artery (ICA) rupture, six were treated with CCA-ICA occlusion and one with graft stenting. The contralateral ICAs were normal or stenotic on angiography in all patients. After the contralateral CCA-ICA rupture, five patients received CCA-ICA occlusion, one received graft stent treatment, and one received no treatment. RESULTS: Five of the seven patients died soon after the final treatment. Two patients developed cerebral infarctions (one treated with bilateral stenting, one treated with occlusion), one died from extensive local infection, one died soon after a third treatment, one died of progression of the disease, and one refused a second treatment and died soon after the diagnostic angiography. Two patients survived with follow-up periods of 1 and 5 years. In all seven patients, the contralateral CCA-ICA blowout occurred within 3 months after the first ICA occlusion. CONCLUSION: Bilateral ICA occlusion is an alternative management for sequential carotid artery blowout, but the mortality is high and outcome is poor. A normal angiogram cannot exclude the possibility of rapid development of a contralateral carotid artery blowout shortly after a first episode in patients who have received radiotherapy for head and neck cancer.

Osteoradionecrosis of the upper cervical spine after radiation therapy for head and neck cancer: differentiation from recurrent or metastatic disease with MR imaging.

PURPOSE: To compare the magnetic resonance (MR) imaging features of upper cervical spine osteoradionecrosis (ORN) with those of recurrent or metastatic disease after the treatment of head and neck malignancies. MATERIALS AND METHODS: This retrospective study was approved by the hospital institutional review board, and the requirement to obtain informed consent was waived. From January 2005 to December 2010, 35 patients who had undergone irradiation of head and neck cancer and who had subsequent C1 or C2 lesions at MR imaging were enrolled. Pathology reports, clinical records, and follow-up MR images were reviewed to classify patients into one of two groups-those with ORN or those with recurrence. The MR imaging characteristics in these patients were evaluated. Statistical significance of intergroup differences was assessed by means of the Pearson χ2 or Fisher exact test for categorical variables and the two-sample t test for continuous variables. RESULTS: ORN was diagnosed in 20 of the 35 patients (57%), and recurrent or metastatic disease was diagnosed in 15 (43%). Ten of the 35 patients (29%) had undergone biopsy of the cervical spine or paraspinal soft tissue. The MR images in the ORN group showed significantly more contiguous involvement of the atlantoaxial or atlanto-occipital bones with intervening joint change (P<.001), more cases of vertebral body collapse (P<.01), more bilateral symmetric involvement of the vertebral body (P<.01), and continuation of vertebral body changes with posterior pharyngeal wall ulceration (P<.01). Posterior arch or other cervical level involvement, paraspinal solid mass, epidural involvement, lateral border cortical destruction, and cervical lymphadenopathy were noted more frequently in the recurrence group than in the ORN group (P=.03, P<.001, P=.02, P<.001, and P<.01, respectively). CONCLUSION: Various MR imaging characteristics can be used to help differentiate between cervical ORN and recurrent disease.

Aggressive revascularization of acute internal carotid artery occlusion in patients with NIHSS>20 and poor collateral circulation: preliminary report.

BACKGROUND: Acute occlusion of internal carotid artery (ICA) is a clinical catastrophic entity with mortality as high as 50%. With innovative devices and technology, we want to clarify the benefit and risk of interventional treatment for those patients. METHODS AND RESULTS: From 2005 to 2009, 62 patients were enrolled and 7 patients were diagnosed as total ICA occlusion with severe neurological deficit and poor collateral circulation received endovascular interventions. Intra-arterial thrombolysis was performed in all the 7 patients. Besides, angioplasty was done in 2 patients, stenting in 3, and thrombosuction in 1. The average NIHSS was 23.3 (standard deviation=3.6) before revascularization, was 14.2(standard deviation=6.8) on day 7. Three patients had symptomatically hemorrhagic transformation and one developed severe brain edema after procedure. Decompressive craniotomy has been conducted in 3, who survived thereafter. One patient died for refusal of decompressive craniotomy. The 30-day modified Rankin scale was 1 in 1, 2 in 1, 3 in 1, and 4 in 3. All of our patients had distal residual lesions at anterior or middle cerebral artery area, and delayed recanalization was noted in 4. CONCLUSIONS: Endovascular therapy was promising as a hyperacute management for patients of ICA total occlusion leading to survival rate more than 80% and significant neurological recovery in 50% of our patients. Distal residual lesions were common in patients of total carotid occlusion after aggressive revascularization. Although the mechanism was not clear, delayed re-canalization was common in such patients.