Ancillary Imaging Research Articles

Enhanced Cortical Excitability in Grapheme-Color Synesthesia and Its Modulation

SummarySynesthesia is an unusual condition characterized by the over-binding of two or more features and the concomitant automatic and conscious experience of atypical, ancillary images or perceptions [1–3]. Previous research suggests that synesthetes display enhanced modality-specific perceptual processing [4–7], but it remains unclear whether enhanced processing contributes to conscious awareness of color photisms. In three experiments, we investigated whether grapheme-color synesthesia is characterized by enhanced cortical excitability in primary visual cortex and the role played by this hyperexcitability in the expression of synesthesia. Using transcranial magnetic stimulation, we show that synesthetes display 3-fold lower phosphene thresholds than controls during stimulation of the primary visual cortex. We next used transcranial direct current stimulation to discriminate between two competing hypotheses of the role of hyperexcitability in the expression of synesthesia. We demonstrate that synesthesia can be selectively augmented with cathodal stimulation and attenuated with anodal stimulation of primary visual cortex. A control task revealed that the effect of the brain stimulation was specific to the experience of synesthesia. These results indicate that hyperexcitability acts as a source of noise in visual cortex that influences the availability of the neuronal signals underlying conscious awareness of synesthetic photisms.

Spontaneous Coronary Artery Dissection: A Disease-Specific, Social Networking Community-Initiated Study

To develop and assess the feasibility of a novel method for identification, recruitment, and retrospective and prospective evaluation of patients with rare conditions. This pilot study is a novel example of "patient-initiated research." After being approached by several members of an international disease-specific support group on a social networking site, we used it to identify patients who had been diagnosed as having at least 1 episode of spontaneous coronary artery dissection and recruited them to participate in a clinical investigation of their condition. Medical records were collected and reviewed, the original diagnosis was independently confirmed by review of imaging studies, and health status (both interval and current) was assessed via specially designed questionnaires and validated assessment tools. Recruitment of all 12 participants was complete within 1 week of institutional review board approval (March 18, 2010). Data collection was completed November 18, 2010. All participants completed the study questionnaires and provided the required medical records and coronary angiograms and ancillary imaging data. This study involving patients with spontaneous coronary artery dissection demonstrates the feasibility of and is a successful model for developing a "virtual" multicenter disease registry through disease-specific social media networks to better characterize an uncommon condition. This study is a prime example of patient-initiated research that could be used by other health care professionals and institutions.

Conservative management of laryngeal perforation in a rural setting: case report and review of the literature on penetrating neck injuries

Penetrating neck injuries (PNIs) are infrequent but can result in significant morbidity and mortality. Although surgical management of unstable patients with penetrating neck trauma is the standard of care, management of stable patients remains controversial owing to the possibility of occult injuries. Recent studies suggest that physical examination and ancillary imaging may be sufficiently accurate to diagnose or rule out surgically significant injuries in PNI. We report a patient with a laryngeal perforation who was managed conservatively in a rural hospital without complications and review the literature pertinent to cases of this nature.

Pigmented Villonodular Synovitis of the Ankle—Radiation Therapy as a Primary Treatment to Reduce Recurrence: A Case Report with 8-year Follow-up

Pigmented villonodular synovitis (PVNS) is a rare, benign, idiopathic proliferative disorder of the synovium that results in villous and or nodular formations that have been reported to manifest within joints, tendon sheaths, and bursae. The overall incidence includes 2% to 10% that occur within the foot and ankle joints. PVNS has a high rate of recurrence and up to a 45% recurrence rate has been reported despite surgical intervention. Although traditional treatment for PVNS includes synovectomy with arthroplasty of the affected joint, radiation therapy is now suggested as an adjunctive therapy that is believed to reduce recurrence of the disease. We present a case of PVNS where the patient was treated in 2 stages: surgical resection of the tumor with arthroplasty of the ankle joint followed by radiation therapy. A retrospective review of the chart, radiographs, and MRIs was conducted for a 36-year-old, African American female who had been treated and followed for 8 years. Pathologic examination of the tumor confirmed the diagnosis of PVNS. No evidence of recurrent PVNS was identified in the long-term postoperative MRI examination. The fact that ancillary imaging examinations failed to reveal evidence of recurrence and that the patient expresses a very high patient satisfaction supports the potential benefit of adjunctive radiation therapy for this condition.

Outpatient Vascular and Interventional Radiology Practice from 2001–2008

To describe experience with an outpatient vascular interventional radiology (IR) practice with respect to number of patients seen, number of procedures performed, and number of imaging studies ordered in follow-up. The outpatient vascular IR practice at the authors' institution was established in 2001 with two physicians spending one half-day per week; a third physician joined in 2004. A retrospective review was done of all patients seen by an interventional radiologist from 2001 to July 2008. The following data were collected for each physician per year: the number of new and established patients seen, the number and type of procedures performed, and the number and type of imaging studies ordered. Data are presented as mean ± standard deviation per physician per year and total number. In 2001, the average number of new patients seen was 61 ± 11 (total number = 122), which peaked in 2006 at 127 ± 28 (total number = 380). A similar trend occurred with the established patients. In 2001, the procedure performed with the greatest frequency was abdominal aortogram with stent placement, which started at 18 ± 2 (total number = 35) and peaked by 2006 at 37 ± 23 (total number = 122). The number of ancillary imaging studies ordered by each physician increased each year and by 2006 was nearly 93 ± 77 (total number = 278). A robust outpatient IR practice in vascular disease can be developed in 3-5 years with downstream imaging studies being ordered for the radiology department.

Abstract No. 352: The outpatient vascular and interventional radiology practice from 2001-2008

To describe our experience with our outpatient vascular interventional radiology (IR) practice with respect to number of patients seen, number of procedures performed, and number of imaging studies ordered in follow-up. Our outpatient vascular IR practice was established in 2001 with two physicians spending 0.1 FTE per year with a third physician joined in 2004. We retrospectively reviewed from all patients seen by an interventional radiologist 2001 to July 2008. The following data were collected for each IR physician per year: the number of new and established patients seen, the number and type of procedures performed, and the number and type of imaging studies ordered. Data are presented as mean ± standard deviation/IR physician/year. In 2001, the average number of new patients seen was 61 ± 11 which peaked by 2006 at 127 ± 28. A similar trend occurred with the established patients. In 2001, the procedure performed with the greatest frequency was abdominal aortogram with stent placement, which started at 18 ± 2 and peaked by 2006 at 37 ± 23. In addition, the number of ancillary imaging ordered by each physician grew each year and by 2006–2007 it was nearly 93 ± 77. A robust outpatient IR practice in vascular disease can be developed in 3–5 years. The interventional radiologist can successfully consult on vascular patients and gradually grow a practice in procedural volume along with downstream imaging studies being ordered for the diagnostic radiology department.

Ultrasonographic-Assisted Ganglion Impar Neurolysis

To the Editor: We applaud the description by Gupta et al.1 of ultrasound-assisted block of the ganlion impar. However, because others may wish to perform this block, additional information, including description of the probe and the angle of insonation, should be included. Also, because some subjects will have a substantial concavity of the sacrum-coccyx, which will make accessing the ganglion using a straight needle difficult, regardless of the ancillary imaging technique, the shape and length of the needle and the type of contrast should be provided. I am especially pleased that, almost two decades after our original description with a specific technique,2 the gate remains open and others have endeavored to improve it. Finally, what is most important is that this tiny structure has been acknowledged as having a pivotal role in pain of sympathetic origin in the perineal pelvic region. Before that description, no clinician had suggested it as a target for the management of severe perineal pain.3 Ricardo Plancarte, MD Instituto Nacional de Cancerología Mexico City, D.F. Mexico [email protected] Julio-César González-Ortiz Instituto Nacional de Cancerología Mexico City, Mexico Jorge Guajardo-Rosas Instituto Nacional de Cancerología Mexico City, Mexico Angel Lee Instituto Nacional de la Nutrición Mexico City, Mexico

Downscaling Cokriging for Super-Resolution Mapping of Continua in Remotely Sensed Images

The main aim of this paper is to show the implementation and application of downscaling cokriging for super-resolution image mapping. By super-resolution, we mean increasing the spatial resolution of satellite sensor images where the pixel size to be predicted is smaller than the pixel size of the empirical image with the finest spatial resolution. It is assumed that coregistered images with different spatial and spectral resolutions of the same scene are available. The main advantages of cokriging are that it takes into account the correlation and cross correlation of images, it accounts for the different supports (i.e., pixel sizes), it can explicitly take into account the point spread function of the sensor, and it has the property of prediction coherence. In addition, ancillary images (topographic maps, thematic maps, etc.) as well as sparse experimental data could be included in the process. The main problem is that super-resolution cokriging requires several covariances and cross covariances, some of which are not empirically accessible (i.e., from the pixel values of the images). In the adopted solution, the fundamental concept is that of covariances and cross-covariance models with point support. Once the set of point-support models is estimated using linear systems theory, any pixel-support covariance and cross covariance can be easily obtained by regularization. We show the performance of the method using Landsat Enhanced Thematic Mapper Plus images.

Occult cholecystitis presenting as PUO demonstrated on Gallium

Gallium-67 scintigraphy is commonly performed to investigate Pyrexia of Unknown Origin (PUO) due to its affinity for infection or inflammation. The dissemination of hybrid SPECT CT imaging allows improved identification and localisation of causes of PUO. A 74 year old male was referred for investigation of pyrexia of unknown origin. Gallium SPECT CT was performed and demonstrated increased Gallium uptake in the gallbladder wall with features of cholelithiasis and collection on the corresponding CT images. At operation the gallbladder revealed areas of chronic cholecystitis and xanthogranulomatous inflammation. Figure 1 Figure 1: A 74 year old male was referred for investigation of pyrexia of unknown origin. A Gallium scan was performed and a whole body planar and SPECT/CT were acquired up to 48 hours following the administration of 300 MBq of Ga-citrate. Gallium SPECT (Top Row) and SPECT/CT fused (Middle Row) images demonstrated increased Gallium uptake in the gallbladder wall (solid arrow). CT (Bottom Row)) images also revealed pericholecystic fat stranding (arrowhead) and a small collection at the interface between the gallbladder and the liver (solid arrow). Occult cholecystitis presenting as PUO demonstrated on Gallium 2 of 3 Figure 2 Figure 2: An ultrasound was performed for further evaluation. The US demonstrated a non-mobile calculus (solid arrow) in the gallbladder neck (Top image) and confirmed cholecystitis (Lower image) with a pericholecystic collection (solid arrow). The patient subsequently underwent laparotomy and cholecystectomy. A 39mm diameter gallstone and a haemorrhagic inflamed gallbladder were removed. Histologic examination revealed organising chronic cholecystitis and areas of xanthogranulomatous inflammation. There are number of causes of PUO including pyogenic infection (soft tissue abscess, pneumonitis, musculoskeletal), non-pyogenic infection (mycobacterial, viral, chronic bacterial, fungal/rickettsial), non-infective inflammation (sarcoidosis, inflammatory bowel disease, vasculitis, “collagen” disease, organ rejection), and neoplasia (haemoproliferative, renal cell carcinoma, melanoma). 1,2 There are a number of proposed mechanisms of 67 Ga uptake into pathologic sites including increased vascular permeability to 67 Ga-transferrin complex, radiotracer accumulation in expanded regional vascular and interstitial fluid spaces, and binding of the metal-protein complex to extravascular transferrin receptors. 3,4,5 Cholecystitis is a relatively common condition usually diagnosed clinically and confirmed by ancillary laboratory investigations and imaging with ultrasound and hepatobiliary scintigraphy. 6,7,8 The addition of Hybrid SPECT CT to 67 Ga scintigraphy improves the sensitivity and specificity of the modality in investigating PUO.

Ablação da fibrilação atrial no Brasil: resultados do registro da Sociedade Brasileira de Arritmias Cardíacas

Aiming to define the profile of curative atrial fibrillation (AF) ablation in Brazil, the Brazilian Cardiac Arrhythmia Society [Sociedade Brasileira de Arritmias Cardíacas] (SOBRAC) created the Brazilian Registry of AF Ablation [Registro Brasileiro de Ablação da FA].To describe the results of this registry.A questionnaire was sent to SOBRAC members asking about data on patients submitted to AF ablation between September 2005 and November, 2006.A total of 29 groups from 13 states completed the forms. Of these, 22 (76%) had performed AF ablations. Between 1998 and 2001, 7 groups (32%) initiated AF ablations and between 2002 and 2006, 15 groups began to perform them (68%). From 1998 to 2006, 2,374 patients were submitted to ablation, 755 (32%) of them during the registry period. Most (70%) were males and 89% presented with paroxysmal or persistent AF. Ancillary imaging methods (intracardiac echocardiography and electroanatomic mapping) were used by 9 groups (41%). During an average five-month follow-up period, total success was 82% and success without use of antiarrhythmic agents was 57%. Nevertheless, 35% of the patients required two or more procedures. There were 111 complications (14.7%) and 2 deaths (0.26%).Curative AF ablation has been increasing significantly in our country, with success rates comparable to international indexes, but often more than one procedure is necessary. Despite promising results, AF ablation still results in significant morbidity. Supplementary imaging methods have been used more and more in an effort to increase efficacy and safety of the procedure. These findings should be considered by public and private funding agencies.

7525 POSTER Treatment of malignant sacral tumors except chordoma

Pigmented villonodular synovitis (PVNS) is a rare, benign, idiopathic proliferative disorder of the synovium that results in villous and or nodular formations that have been reported to manifest within joints, tendon sheaths, and bursae. The overall incidence includes 2% to 10% that occur within the foot and ankle joints. PVNS has a high rate of recurrence and up to a 45% recurrence rate has been reported despite surgical intervention. Although traditional treatment for PVNS includes synovectomy with arthroplasty of the affected joint, radiation therapy is now suggested as an adjunctive therapy that is believed to reduce recurrence of the disease. We present a case of PVNS where the patient was treated in 2 stages: surgical resection of the tumor with arthroplasty of the ankle joint followed by radiation therapy. A retrospective review of the chart, radiographs, and MRIs was conducted for a 36-year-old, African American female who had been treated and followed for 8 years. Pathologic examination of the tumor confirmed the diagnosis of PVNS. No evidence of recurrent PVNS was identified in the long-term postoperative MRI examination. The fact that ancillary imaging examinations failed to reveal evidence of recurrence and that the patient expresses a very high patient satisfaction supports the potential benefit of adjunctive radiation therapy for this condition.

Syphilitic Scleritis and Choroidal Malignant Melanoma of the Same Eye

A 42-year-old Italian homosexual presented with a red painful eye associated with exudative retinal detachment that was subsequently attributed to syphilitic posterior scleritis. These findings all resolved with intravenous penicillin therapy. However, choroidal mass lesion persisted and subsequent ancillary imaging including B scan and ultrasonography confirmed the presence of a choroidal melanoma, which was treated with radioactive plaque therapy. This case report will describe the interesting findings of this unique presentation.

Downscaling cokriging for image sharpening

The main aim of this paper is to show the utility of cokriging for image fusion (i.e. increasing the spatial resolution of satellite sensor images). It is assumed that co-registered images with different spatial and spectral resolutions of the same scene are available and the task is to generate new remote sensing images at the finer spatial resolution for the spectral bands available only at the coarser spatial resolution. The main advantages of cokriging are that it takes into account the correlation and cross-correlation of images, it accounts for the different supports (i.e. pixel sizes), it can take into account explicitly the point spread function of the sensor and has the property of prediction coherence. In addition, ancillary images (topographic maps, thematic maps, etc.) as well as sparse experimental data could be included in the process. The main drawback of cokriging in the previous context is that it requires several covariances and cross-covariances some of which are not accessible empirically (i.e. from the pixel values of the images). The solution adopted in this paper was to use linear systems theory to obtain the required covariances from the ones that were estimated empirically. Cokriging was compared with a benchmark image fusion approach (the high pass filter method) to assess performance against a standard. In fact, cokriging may be seen as a generalization of the high pass filter method where the low pass filter and high pass filter are estimated by fitting parameters to data. The present paper discusses the downscaling cokriging method, shows its implementation and illustrates the process in the case of sharpening several remotely sensed images. The desired target image was known so that the performance of the method could be evaluated realistically. Different statistics were used to show that the cokriged predictions were more precise than the HPF predictions. Downscaling cokriging is a new method of great potential in remote sensing that should be incorporated to the toolkit of the remote sensing researcher.

Imaging Patients with Heart Failure: Expectations of the Clinician

Obviously the clinical evaluation of a patient who is known to have, or suspected of having, heart failure is extraordinarily important. All of the world’s major societies with guidelines for diagnosing and managing patients who have heart failure have emphasized the importance of a complete evaluation [1–4]. Diagnostic tools are essential to help the skilled clinician define the illness and manage these individuals to achieve optimal outcomes. A variety of tests assist with the clinical evaluation of patients during the initial presentation as well as at long-term follow-up points. Specifically, the clinician is challenged when choosing from the wide spectrum of noninvasive imaging techniques that is available to assist with the task. The clinician’s expectations that the results of these tests will be helpful should be high, because individualized care of patients who have heart failure is critically important and is based largely on results that emerge from imaging evaluations. The complete evaluation of an individual who has heart failure demands synthesizing and integrating clinical data that are obtained during history taking and physical examination as well as studying ancillary laboratory test results, physiologic performance, and imaging modalities. Although no one test should be used to diagnose heart failure, determine prognosis, or guide therapy and interventions, imaging procedures dominate these decisions. Therefore,

Masses and pseudomasses of the kidney: imaging spectrum on MR.

MR imaging is useful in differentiating and characterizing renal masses. A careful evaluation of the signal characteristics and morphology of a renal mass combined with the ancillary imaging findings and patient history should assist the radiologist in making the proper diagnosis or recommending the appropriate treatment in most cases. This pictorial essay demonstrates the typical MR imaging features of common renal masses including renal cell carcinoma (RCC), oncocytoma, angiomyolipoma, metastases, transitional cell carcinoma (TCC), lymphoma, and arteriovenous malformation (AVM), and highlights several potential diagnostic pitfalls in making the proper diagnosis.

An integrative classification of vegetation in China based on NOAA AVHRR and vegetation-climate indices of the Holdridge life zone

We developed a method for integrated analysis of multi-source data for vegetation classification at the continental scale, and applied it to China. Multi-temporal 1 km NOAA Advanced Very High Resolution Radiometer (AVHRR) Holdridge's life zone system and its vegetation-climate classification indices such as bio-temperature (BT), potential evapotranspiration rate (PER) and precipitation ( P ) correspond better with undisturbed vegetation types all over the world. We generated 1 km images of BT, PER and P using the quantitative model of Holdridge's life zone system with climate data of China. They were processed with principal component analysis (PCA) to produce an ancillary image. This image and 12 monthly images of maximum Normalized Difference Vegetation Index (NDVI) values at 1 km resolution were input into an ISODATA clustering algorithm to carry out a vegetation classification. As a result, 47 information classes were obtained. Seasonal NDVI parameters derived through time series analysis (TSA) of the NDVI temporal profile and a set of quantitative vegetation-climate parameters of Holdrige's life zone model were synthetically utilized to label information classes. In this method, climate, terrain and spectral data were integrated; separability between vegetation types and classification accuracy were improved. A total of 47 land cover classes were obtained. Validation data collected in the field using GPS indicated that an overall classification accuracy of 71.4% was reached, an 8.1% improvement to the map derived only from multi-temporal NDVI images. To compare our results with the International Geosphere-Biosphere Programme (IGBP) DISCover land cover dataset, we aggregated our land cover classes according to the IGBP classification system. The overall classification accuracy for the aggregated vegetation map from our classification results improved IGBP land cover map from 75.5% to 86.3%.

Fractures of the carpal bones excluding the scaphoid

Carpal fractures excluding the scaphoid can cause morbidity that is disproportionate to their incidence because they are easily overlooked and are often harbingers of a wider wrist injury. Failure to recognize a more global injury pattern can result in undertreatment and permanent wrist dysfunction. Diagnosis requires a high index of suspicion, familiarity with carpal topography to guide the physical examination, and judicious use of specialized radiographic views and ancillary imaging techniques. Copyright © 2002 by the American Society for Surgery of the Hand

Estimation and mapping of forest stand density, volume, and cover type using the k-nearest neighbors method

Mapping forest variables and associated characteristics is fundamental for forest planning and management. Considerable effort has been made in Northern Europe to develop techniques for wall-to-wall mapping of forest variables. Following that work, we describe the k-nearest neighbors (kNN) method for improving estimation and to produce wall-to-wall basal area, volume, and cover type maps, in the context of the USDA Forest Service's Forest Inventory and Analysis (FIA) monitoring system. Several variations within the kNN were tested, including: distance metric, weighting function, feature weighting parameters, and number of neighbors. Specific procedures to incorporate ancillary information and image enhancement techniques were also tested. Using the nearest neighbor ( k=1), Euclidean distance, a three date 18-band composite image, and feature weighting parameters, maps were constructed for basal area, volume, and cover type. The empirical, bootstrap based, 95% confidence interval for the basal area root mean square error (MSE) is (8.21, 9.02) m 2/ha and for volume (48.68, 54.58) m 3/ha. For the 13 FIA forest cover type classes, results indicated useful map accuracy and the choice of k=1 retained the full range of forest types present in the region. The 95% confidence interval, obtained using the bootstrap 0.632+ technique, for the overall accuracy (OA) in the 13 cover type classification was (0.4952, 0.5459). Recommendations for applying the kNN method for mapping and regional estimation are provided.

Role of immunocytochemistry and DNA flow cytometry in the fine-needle aspiration diagnosis of malignant small round-cell tumors.

In the present study, DNA flow cytometry (FCM) and immunocytochemistry (ICC) with a selected panel of antibodies were performed on 51 cases of malignant tumors which were referred for fine-needle aspiration biopsy (FNAB) to our Department of Cytology for the last 2 yr. Twelve cases were diagnosed as neuroblastoma, 16 as Ewing's sarcoma, 2 as retinoblastoma, 5 as non-Hodgkin's lymphoma (NHL), 5 as rhabdomyosarcoma, 2 as peripheral neuroectodermal tumors (PNETs), and 8 as Wilms' tumor. Eleven of 12 neuroblastomas were diploid by FCM, and 1 was aneuploid, with an S-phase fraction (SPF) of 8.3%. Neuron-specific enolase (NSE) was negative in 3 and positive in 8 cases of neuroblastoma, whereas neuroblastoma marker was positive in 3/11. Sixteen of 17 Ewing's sarcomas were diploid, and 1 showed tetraploid aneuploidy, with an SPF of 10.06%. Eight of 13 Ewing's sarcomas were positive for Mic-2 gene product (Ewing's marker). All 5 NHL were positive for leukocyte-common antigen (LCA). Three of 5 rhabdomyosarcomas were diploid, and 2 cases showed aneuploidy. Rhabdomyosarcoma showed muscle-specific actin positivity in 4 and desmin positivity in 3 cases. All 3 cases of PNET were diploid and positive for the Mic-2 gene product, whereas NSE and vimentin were positive in 2 cases. Both cases of retinoblastoma were diploid. Immunostaining was noncontributory in 1 case, and the other showed positivity for the retinoblastoma gene product, NSE, and chromogranin. Seven of 8 Wilms' tumors were diploid, and 1 showed aneuploid, with an SPF of 11.13%. Seven of 8 Wilms' tumors were positive for cytokeratin (CK), 5 were positive for NSE, 6 were positive for epithelial membrane antigen (EMA), and 5 were positive for vimentin. FNAB diagnosis of malignant round-cell tumors is difficult only by light microscopy. Due to the availability of specific markers for subgrouping tumors, ICC has proved to be more useful these days, while DNA FCM has little diagnostic value, as most of them are diploid. Further ancillary studies, e.g., electron microscopy, image analysis, and other molecular investigations, are required to further categorize these tumors more precisely for better clinical management of these cases.

The limping child

The limping child often presents to the emergency department with a nonspecific history and physical examination. The components of gait, the pathophysiology of specific abnormalities, and the conditions that may produce long-term morbidity must be identified expeditiously to assure return to normal function. Ancillary data and imaging may be essential for appropriate management.