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Reyes S, Viswanathan A, Godin O, Dufouil C, Benisty S, Hernandez K, Kurtz A, Jouvent E, O'Sullivan M, Czernecki V, Bousser MG, Dichgans M, Chabriat H. Apathy: A major symptom in CADASIL. Neurology 2009; 72:905-10. [DOI: 10.1212/01.wnl.0000344166.03470.f8] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Viswanathan A, Raj S, Greenberg SM, Stampfer M, Campbell S, Hyman BT, Irizarry MC. Plasma Abeta, homocysteine, and cognition: the Vitamin Intervention for Stroke Prevention (VISP) trial. Neurology 2009; 72:268-72. [PMID: 19153374 DOI: 10.1212/01.wnl.0000339486.63862.db] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Amyloid-beta protein (Abeta) plays a key role in Alzheimer disease (AD) and is also implicated in cerebral small vessel disease. Serum total homocysteine (tHcy) is a risk factor for small vessel disease and cognitive impairment and correlates with plasma Abeta levels. To determine whether this association results from a common pathophysiologic mechanism, we investigated whether vitamin supplementation-induced reduction of tHcy influences plasma Abeta levels in the Vitamin Intervention in Stroke Prevention (VISP) study. METHODS Two groups of 150 patients treated with either the high-dose or low-dose formulation of pyridoxine, cobalamin, and folic acid in a randomized, double-blind fashion were selected among the participants in the VISP study without recurrent stroke during follow-up and in the highest 10% of the distribution for baseline tHcy levels. Concentrations of plasma Abeta with 40 (Abeta40) and 42 (Abeta42) amino acids were measured at baseline and at the 2-year visit. RESULTS tHcy levels significantly decreased with vitamin supplementation in both groups. tHcy were strongly correlated with Abeta40 but not Abeta42 concentrations. There was no difference in the change in Abeta40, Abeta42 (p = 0.40, p = 0.35), or the Abeta42/Abeta40 ratio over time (p = 0.86) between treatment groups. Abeta measures were not associated with cognitive change. CONCLUSIONS This double-blind randomized controlled trial of vitamin therapy demonstrates a strong correlation between serum tHcy and plasma Abeta40 concentrations in subjects with ischemic stroke. Treatment with high dose vitamins does not, however, influence plasma levels of Abeta, despite their effect on lowering tHcy. Our results suggest that although tHcy is associated with plasma Abeta40, they may be regulated by independent mechanisms.
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Viswanathan A, Relyea K, Whitehead WE, Curry DJ, Luerssen TG, Jea A. Pneumothorax complicating "in-out-in" thoracic pedicle screw placement for kyphotic deformity correction in a child. J Neurosurg Pediatr 2008; 2:379-84. [PMID: 19035680 DOI: 10.3171/ped.2008.2.12.379] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The authors describe a rare case of pneumothorax as a complication of thoracic pedicle screw placement in an 11-year-old girl undergoing posterior segmental instrumentation for a kyphotic deformity. Spontaneous pneumothorax after posterior fusion for adolescent idiopathic scoliosis has been reported in the orthopedic literature; however, to the best of the authors' knowledge, pneumothorax directly related to pedicle screw placement for spinal deformity has not been previously described. The authors discuss the anatomical and technical aspects leading to this complication and the lessons learned from it.
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Nandigam RNK, Viswanathan A, Delgado P, Skehan ME, Smith EE, Rosand J, Greenberg SM, Dickerson BC. MR imaging detection of cerebral microbleeds: effect of susceptibility-weighted imaging, section thickness, and field strength. AJNR Am J Neuroradiol 2008; 30:338-43. [PMID: 19001544 DOI: 10.3174/ajnr.a1355] [Citation(s) in RCA: 290] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
BACKGROUND AND PURPOSE The emergence of cerebral microbleeds (CMB) as common MR imaging findings raises the question of how MR imaging parameters influence CMB detection. To evaluate the effects of modified gradient recalled-echo (GRE) MR imaging methods, we performed an analysis of sequence, section thickness, and field strength on CMB imaging properties and detection in subjects with cerebral amyloid angiopathy (CAA), a condition associated with microhemorrhage. MATERIALS AND METHODS Multiple MR images were obtained from subjects with probable CAA, with varying sequences (GRE versus susceptibility-weighted imaging [SWI]), section thicknesses (1.2-1.5 versus 5 mm), and magnetic field strengths (1.5T versus 3T). Individual CMB were manually identified and analyzed for contrast index (lesion intensity normalized to normal-appearing white matter signal intensity) and diameter. CMB counts were compared between 1.5T thick-section GRE and thin-section SWI for 3 subjects who underwent both protocols in the same scanning session. RESULTS With other parameters constant, use of SWI, thinner sections, and a higher field strength yielded medium-to-large gains in CMB contrast index (CI; Cohen d 0.71-1.87). SWI was also associated with small increases in CMB diameter (Cohen d <0.3). Conventional thick-section GRE identified only 33% of CMB (103 of 310) seen on thin-section SWI. Lesions prospectively identified on GRE had significantly greater CI and diameter measured on the GRE image than those not prospectively identified. CONCLUSIONS The examined alternatives to conventional GRE MR imaging yield substantially improved CMB contrast and sensitivity for detection. Future studies based on these techniques will most likely yield even higher prevalence estimates for CMB.
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Viswanathan A, Gschwendtner A, Guichard JP, Buffon F, Cumurciuc R, O'Sullivan M, Holtmannspötter M, Pachai C, Bousser MG, Dichgans M, Chabriat H. Lacunar lesions are independently associated with disability and cognitive impairment in CADASIL. Neurology 2007; 69:172-9. [PMID: 17620550 DOI: 10.1212/01.wnl.0000265221.05610.70] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a hereditary arteriopathy caused by mutations of the Notch3 gene. The disease is characterized by T2-hyperintense lesions (subcortical white matter lesions), T1-hypointense lesions (lacunar lesions), and T2*-weighted gradient-echo (GE) lesions (cerebral microhemorrhages [CMs]) visualized on clinical MRI sequences and is considered as a model of "pure" subcortical ischemic vascular dementia. Although numerous studies have investigated the impact of white matter lesions in patients with CADASIL, the clinical importance of lacunar lesions remains unknown. Our purpose was to examine the influence of the visible MRI markers in the disease, including the load of lacunar lesions on cognitive impairment and disability in CADASIL. METHODS We collected clinical data from 147 consecutive patients enrolled in an ongoing two-center prospective cohort study. Degree of disability was assessed by modified Rankin scale and Barthel index. Degree of cognitive impairment was assessed by Mattis Dementia Rating Scale and Mini-Mental Status Examination. T1-weighted, fluid-attenuated inversion recovery, and GE images were obtained on a 1.5-T MRI. Volume and location of lacunar lesions, white matter hyperintensities (WMHs), and CMs were assessed. RESULTS There was a significant independent association between age, volume of lacunar lesions, and global cognitive function scales when analyzed in a multivariable model. In contrast, WMHs and CMs had no independent influence on cognitive function. Disability in this cohort was associated with volume of lacunar lesions, CMs, systolic blood pressure, and age but not with WMHs. CONCLUSIONS Among the lesions observed on conventional MRI in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), the overall lacunar lesion burden seems to have the most important impact on cognitive function and disability. These findings suggest that preventive strategies to decrease the risk of lacunar lesions as observed on MRI may reduce disease-related impairment in CADASIL. These results suggest that lacunar lesions may also play a key role in disability and cognitive impairment in more common forms of small-vessel disease.
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Viswanathan A, Horick N, Tanaka C, Campos S, Matulonis U, Berkowitz R. Chemotherapy and radiation therapy in UPSC. J Clin Oncol 2007. [DOI: 10.1200/jco.2007.25.18_suppl.5535] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
5535 Purpose: To analyze the impact of chemotherapy (Ch) and radiation therapy (RT) on relapse rates in patients with uterine papillary serous carcinoma (UPSC). Materials and Methods: The outcomes of 160 women with UPSC seen between 1980–2005 at the BW/DFCC were analyzed. Exclusion criteria included stage IVB disease, no hysterectomy, unknown stage, or unknown type of RT. Results: The median age was 67 years (range 31–90). FIGO Stage was IA (21), IB (28), IC (13), IIA (7), IIB (10), IIIA (42), IIIB (2), IIIC (21), and IVA (16). Treatment included none (40), Ch alone (20), Ch and whole abdominal radiation (WA) (11), Ch and pelvic radiation (P) (30), Ch and vaginal brachytherapy (VB) (2), WA alone (24), P alone (19), and VB alone (14). The median dose of RT was WA 30 Gy and P 45 Gy. Ch was given to 63 patients; the median number of cycles of Carboplatin, Adriamycin and Paclitaxel was 3. Overall survival (OS) and disease-free survival (DFS) for the entire group were 67% and 57% at 2 years, 62% and 51% at 3 years and 51% and 38% at 5 years. A total of 58 patients relapsed. Among those who received no RT or Ch, 48% (19/40) relapsed; among those treated with Ch only, 50% (10/20) relapsed; in the group treated with RT only, 26% (15/57) relapsed; and, in those treated with Ch and RT, 33% (14/43) relapsed. A significant difference in recurrence rate was seen in patients treated with RT compared to those who received no treatment (OR 0.40, p=0.03). This difference persisted after controlling for Stage, which did significantly affect the relationship between RT treatment and recurrence. Local recurrence (in an RT field) was a component of failure for 14% (14/100) treated with RT, versus 42% (25/59) that received no RT (OR 0.22, p=0.0001). Distant metastases were a component of first failure in 15% (9/61) that received Ch versus 11% (11/97) that did not; there was no significant difference in distant recurrence rate for patients treated with Ch (OR 1.35, p=0.53). Conclusion: This single-institution study represents the largest series of UPSC to date. The use of RT significantly decreases the overall recurrence rate of UPSC in this series and should be considered in patients with stages I-IVA UPSC. Future studies looking at the optimal type, dose and duration of chemotherapy, as well as the use of novel agents, are needed to improve outcomes in this population. No significant financial relationships to disclose.
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Lim WT, Zhang WH, Miller CR, Watters JW, Gao F, Viswanathan A, Govindan R, McLeod HL. PTEN and phosphorylated AKT expression and prognosis in early- and late-stage non-small cell lung cancer. Oncol Rep 2007. [PMID: 17342327 DOI: 10.3892/or.17.4.853] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Non-small cell lung cancer (NSCLC) is the commonest cause of cancer mortality worldwide. Growth factor receptor signalling pathways constitute an important mediator for tumor growth and proliferation. PTEN and pAKT play important roles in regulating signal transduction along this pathway. Separate cohorts of stage I (n=25) and stage IV (n=34) NSCLC were examined by immunohistochemistry for PTEN and pAKT expression. There was no correlation between PTEN expression and pAKT expression and neither were associated with age, sex or smoking status. Patients with stage IV disease who overexpressed pAKT (at least 2+) or were PTEN-null had poorer overall survival and progression-free survival. This suggests that PTEN-null or pAKT-positive tumors constitute more aggressive tumors whose clinical course is not altered by therapy. There was no difference in the clinical outcome for stage I disease by PTEN or pAKT expression. A greater proportion of the stage IV patients had PTEN-null disease compared to the stage I cohort, suggesting that loss of PTEN is important in the tumor biology of advanced disease. Loss of PTEN or overexpression of pAKT predicts for an aggressive subset of lung tumors that have a poor prognosis. This will allow identification of a poor prognosis subset that can be targeted with novel treatments that either restore PTEN function or target activated AKT, mTOR and other downstream signal transduction molecules.
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Lim WT, Zhang WH, Miller CR, Watters JW, Gao F, Viswanathan A, Govindan R, McLeod HL. PTEN and phosphorylated AKT expression and prognosis in early- and late-stage non-small cell lung cancer. Oncol Rep 2007; 17:853-7. [PMID: 17342327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/14/2023] Open
Abstract
Non-small cell lung cancer (NSCLC) is the commonest cause of cancer mortality worldwide. Growth factor receptor signalling pathways constitute an important mediator for tumor growth and proliferation. PTEN and pAKT play important roles in regulating signal transduction along this pathway. Separate cohorts of stage I (n=25) and stage IV (n=34) NSCLC were examined by immunohistochemistry for PTEN and pAKT expression. There was no correlation between PTEN expression and pAKT expression and neither were associated with age, sex or smoking status. Patients with stage IV disease who overexpressed pAKT (at least 2+) or were PTEN-null had poorer overall survival and progression-free survival. This suggests that PTEN-null or pAKT-positive tumors constitute more aggressive tumors whose clinical course is not altered by therapy. There was no difference in the clinical outcome for stage I disease by PTEN or pAKT expression. A greater proportion of the stage IV patients had PTEN-null disease compared to the stage I cohort, suggesting that loss of PTEN is important in the tumor biology of advanced disease. Loss of PTEN or overexpression of pAKT predicts for an aggressive subset of lung tumors that have a poor prognosis. This will allow identification of a poor prognosis subset that can be targeted with novel treatments that either restore PTEN function or target activated AKT, mTOR and other downstream signal transduction molecules.
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Sullivan M, Ngo E, Viswanathan A, Jouvent E, Gschwendtner A, Saemann P, Duering M, Pachai C, Bousser M, Chabriat H, Dichgans M. Hippocampal volume is an independent predictor of global cognitive performance in pure cerebral small vessel disease. AKTUELLE NEUROLOGIE 2007. [DOI: 10.1055/s-2007-988009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Borgert J, Krüger S, Timinger H, Krücker J, Glossop N, Durrani A, Viswanathan A, Wood BJ. Respiratory motion compensation with tracked internal and external sensors during CT-guided procedures. ACTA ACUST UNITED AC 2006; 11:119-25. [PMID: 16829505 PMCID: PMC2386886 DOI: 10.3109/10929080600740871] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
This paper investigates the possibility of using the motion of a patient's anterior surface in combination with a motion model to compensate for internal respiratory motion during tracked biopsies. Position data from two electromagnetically tracked sensors, one placed on the patient's sternum, the other incorporated into a biopsy needle, were acquired during a liver biopsy. The data were used to evaluate the correlation between the position measurements of the two sensors and to derive an affine motion model to assess respiratory motion compensation for image-guided interventional procedures. The correlation reached up to 94% for ranges of steady respiration. The residual motion of the internal sensor after compensation is reduced by a factor of approximately four.
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Borgert J, Krüger S, Timinger H, Krücker J, Glossop N, Durrani A, Viswanathan A, Wood BJ. Respiratory motion compensation with tracked internal and external sensors during CT-guided procedures. COMPUTER AIDED SURGERY : OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY FOR COMPUTER AIDED SURGERY 2006. [PMID: 16829505 DOI: 10.1080/10929080600740871] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 09/30/2022]
Abstract
This paper investigates the possibility of using the motion of a patient's anterior surface in combination with a motion model to compensate for internal respiratory motion during tracked biopsies. Position data from two electromagnetically tracked sensors, one placed on the patient's sternum, the other incorporated into a biopsy needle, were acquired during a liver biopsy. The data were used to evaluate the correlation between the position measurements of the two sensors and to derive an affine motion model to assess respiratory motion compensation for image-guided interventional procedures. The correlation reached up to 94% for ranges of steady respiration. The residual motion of the internal sensor after compensation is reduced by a factor of approximately four.
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Chen YW, Gurol ME, Rosand J, Viswanathan A, Rakich SM, Groover TR, Greenberg SM, Smith EE. Progression of white matter lesions and hemorrhages in cerebral amyloid angiopathy. Neurology 2006; 67:83-7. [PMID: 16832082 PMCID: PMC1502246 DOI: 10.1212/01.wnl.0000223613.57229.24] [Citation(s) in RCA: 128] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To determine the rate of progression of white matter lesions and hemorrhages in a cohort with cerebral amyloid angiopathy (CAA). METHODS The authors analyzed data from 26 patients with possible (3) or probable (23) CAA, diagnosed by the Boston Criteria. Brain maps of white matter hyperintensities, normalized to head size (nWMH), were created by blinded computer-assisted segmentation of MRI images obtained at baseline and after a median follow-up interval of 1.1 year. RESULTS There was a substantial nWMH volume increase over the interscan interval (median 0.5 mL/year, interquartile range 0.1 to 2.8, p < 0.001). The median yearly increase, expressed as a percentage of the baseline WMH volume, was 18%. The characteristic most strongly associated with nWMH volume increase was the baseline nWMH volume (r = 0.57, p = 0.002). The volume of nWMH progression was also associated with history of cognitive impairment (median 5.0 mL/year in cognitively impaired subjects vs 0.3 mL/year in cognitively unimpaired, p = 0.02) but not age or hypertension. This association remained present in an analysis stratified by baseline WMH volume. New hemorrhages, including asymptomatic microbleeds, were seen in 46% of subjects. The number of new MRI hemorrhages correlated strongly with baseline nWMH (r = 0.53, p = 0.005) but not with nWMH progression (r = 0.22, p = 0.28). CONCLUSIONS There is a progressive increase in white matter lesions in subjects with cerebral amyloid angiopathy. The association of white matter lesions with incident lobar hemorrhages suggests that white matter damage may reflect a progressive microangiopathy due to cerebral amyloid angiopathy.
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Velcheti V, Viswanathan A, Sainani N, Grove L, Suresh R, Baggstrom MQ, Govindan R. Presentation of non-small cell lung cancer (NSCLC) in octogenarians. J Clin Oncol 2006. [DOI: 10.1200/jco.2006.24.18_suppl.18555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
18555 Background: Lung cancer is the most common cause of cancer related death in the United States. Non-small cell lung cancer (NSCLC) accounts for over 80% of all new cases of lung cancer. Lung cancer is a disease of the elderly. There are only limited data available on NSCLC in octogenarians. Methods: From our institutional tumor registry, we identified all patients with NSCLC from 1995 to 2002 who were 80 years or older at the time of initial presentation. Data regarding overall stage, histology, date and extent of surgery, and co-morbidities were analyzed. Co-morbidity determination was based on the Adult Co-morbidity Evaluation (ACE-27) test, which ranges from 0 to 3 depending on severity of co-existing conditions. Results: At the time of initial presentation with NSCLC, 236 pts were 80 years or older. The distribution of stages were: stage I in 93 pts (39.5%), stage II in 15 pts (6.5%), stage III in 66 pts (28%) and stage IV in 62 pts (26%). Of the 236 patients the co-morbidity score was known for 223 pts. The distribution of the known scores was: 0, 39 pts (17.5%); 1, 79 pts (35%); 2, 68 pts (30.5%); and 3, 37 pts (17%). Only 35 patients in this cohort underwent surgery. Conclusions: 1. Despite a high proportion (46%) of early stage NSCLC, only a few elderly patients 80 years or older undergo surgical resection, likely because of co-morbid conditions. 2. Innovative non-surgical local modalities of therapy need to be studied in this population. No significant financial relationships to disclose.
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Baggstrom MQ, Gilstrap E, Skelton A, Viswanathan A, Morgensztern D, Nations PA, Foersterling D, Govindan R. Barriers for accrual to clinical trials in adult patients (pts) with thoracic malignancies. J Clin Oncol 2006. [DOI: 10.1200/jco.2006.24.18_suppl.6058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
6058 Background: Despite recent advances in the treatment of pts with thoracic malignancies, the outcome continues to be poor. Only about 3% of all adult oncology pts enroll in clinical trials compared to approximately 50% of pediatric pts. The proportion of adult pts enrolled in clinical trials is low, even in tertiary cancer centers. It is critical to understand the barriers for accrual to clinical trials. Methods: We reviewed the outpatient charts of all pts with thoracic malignancies (non-small cell lung cancer [NSCLC], small cell lung cancer, and esophageal cancer) referred to the thoracic medical oncology group at our institution from 11/1/2004 to 10/31/2005. Available and appropriate clinical trials are presented to the pts routinely and reasons for non-enrollment are documented. We collected information on histology, stage, performance status (PS) and co-morbid conditions. Appropriate studies at the time of initial consultation were noted from database. Results: Of 284 consecutive patient charts reviewed, 13 pts (4.6%) did not require therapy, 6 pts (2.1%) were deemed to have a non-thoracic primary on review, and 15 pts (5.3%) had already initiated therapy at the time of consultation. Of the remaining 250 evaluable pts, 88 pts (35.2%) were not enrolled because of lack of available appropriate clinical trials at the time of initial consultation. The most common categories were adjuvant therapy for early stage NSCLC and advanced esophageal cancer. Twenty-one pts (8.4%) enrolled onto a clinical trial. The most common reasons for not participating in a clinical trial include: ineligibility due to PS (28 pts, 11.2%), geographic issues (23 pts, 9.2%), patient refusal (16 pts, 6.4%) and co-morbid conditions (9 pts, 3.6%). Ten pts (4.0%) were lost to follow up. Conclusions: 1. Lack of appropriate and available clinical trials and poor PS are the two most common reasons for lack of patient enrollment in clinical trials at our institution. 2. It is critical to develop innovative clinical trials for pts with advanced esophageal cancer, adjuvant therapy in early stage NSCLC, and poor PS. 3. More work is needed to understand patient perception about clinical trials. [Table: see text]
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Banes MJ, Culham LE, Bunce C, Xing W, Viswanathan A, Garway-Heath D. Agreement between optometrists and ophthalmologists on clinical management decisions for patients with glaucoma. Br J Ophthalmol 2006; 90:579-85. [PMID: 16622087 PMCID: PMC1857057 DOI: 10.1136/bjo.2005.082388] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BACKGROUND/AIMS Although optometrists have become an accepted part of the team in many hospital glaucoma clinics, their decision making ability has not been assessed formally. This study aims to document the accuracy and safety of clinical work undertaken by optometrists in the hospital setting by investigating their management decisions on follow up of patients with glaucoma. METHODS Four optometrists and three medical clinicians examined 50 patients each. Clinical findings were recorded as usual in the hospital records but management decisions were documented separately on a specially designed data collection form. Subsequently, the patient records and clinical findings were reviewed retrospectively and independently by two consultant ophthalmologists, who were masked to the management decisions of the optometrists and medical clinicians. The consultants' management decisions were then compared with those made by the optometrists and medical clinicians. Percentage agreements were computed together with kappa (kappa), or weighted kappa, statistics where appropriate. RESULTS Agreement between consultants and optometrists was 55% (kappa = 0.33) for evaluation of visual field status, 79% (kappa = 0.67) for medical management, 72-98% for other aspects of patient management, and 78% (weighted kappa = 0.35) for scheduling of next clinic appointment. Very similar levels of agreement were found between consultants and medical clinicians. CONCLUSION Agreement between optometrists and consultants, in glaucoma clinical decision making, was at least as good as that between medical clinicians and consultants. Within an appropriate environment, optometrists can safely work as part of the hospital glaucoma team in outpatient clinics.
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Xiong L, Viswanathan A, Stewart A, Cormack R. SU-FF-T-111: Bladder Dose Distribution in Cylindrical Brachytherapy Treatment. Med Phys 2006. [DOI: 10.1118/1.2241036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Viswanathan A, Rakich SM, Engel C, Snider R, Rosand J, Greenberg SM, Smith EE. Antiplatelet use after intracerebral hemorrhage. Neurology 2006; 66:206-9. [PMID: 16434655 DOI: 10.1212/01.wnl.0000194267.09060.77] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Survivors of intracerebral hemorrhage are at risk for recurrent intracerebral hemorrhage and ischemic cardiovascular and cerebrovascular disease. OBJECTIVE To determine whether antiplatelet therapy increases the risk of recurrent intracerebral hemorrhage. METHODS The authors reviewed data from consecutive survivors of primary intracerebral hemorrhage enrolled in a single-center prospective cohort study. Survivors were followed by telephone interview; recurrent intracerebral hemorrhage and post-index antiplatelet agent use and duration were recorded. Cox proportional hazards models was used with antiplatelet agent exposure as a time-dependent variable to assess the effect of antiplatelet agent use on recurrent intracerebral hemorrhage, stratified by lobar and deep hemispheric location. RESULTS Recurrent intracerebral hemorrhage was more common in survivors of lobar hemorrhage compared with survivors of deep hemorrhage (cumulative 2-year rate 22% vs 4%; p = 0.007). Antiplatelet agents were prescribed in 22% of intracerebral hemorrhage survivors (27/127 lobar, 19/80 deep hemispheric), most commonly for prevention of ischemic heart disease. Antiplatelet agent use was not associated with intracerebral hemorrhage recurrence in survivors of either lobar hemorrhage (hazard ratio [HR] 0.8, 95% CI 0.3 to 2.3, p = 0.73) or of deep hemorrhage (HR 1.2, 95% CI 0.1 to 14.3, p = 0.88). CONCLUSION Antiplatelet agent use is relatively common following intracerebral hemorrhage but did not appear to be associated with a large increased risk of intracerebral hemorrhage recurrence in this observational study.
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Xiong L, Viswanathan A, Stewart A, Haker S, Tempany C, Cormack R. SU-FF-J-98: Feasibility of Deformable Structure Registration Towards Calculation of Cumulative Dose Distributions. Med Phys 2005. [DOI: 10.1118/1.1997644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Morgensztern D, Lim WT, Subramanian J, Viswanathan A, Govindan R. Third-line chemotherapy with gemcitabine or docetaxel in patients with advanced non-small cell lung cancer (NSCLC). J Clin Oncol 2005. [DOI: 10.1200/jco.2005.23.16_suppl.7298] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Goodgame B, Viswanathan A, Pillot G, Gao F, Morgensztern D, Bradley J, Guthrie T, Battafarano R, Govindan R. Outcomes in 708 resected stage I non-small cell lung cancer (NSCLC) subjects and a prognostic index for relapse. J Clin Oncol 2005. [DOI: 10.1200/jco.2005.23.16_suppl.7198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Viswanathan A, Jhingran A, Deavers M, Ramirez P, Eifel P. Patterns of failure in small cell carcinoma of the cervix. Int J Radiat Oncol Biol Phys 2002. [DOI: 10.1016/s0360-3016(02)03126-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Viswanathan A, Rao KM, Palaniappan M, Muralidharan S. Complete transection of cervical trachea following blunt trauma — A case report. Indian J Thorac Cardiovasc Surg 2001. [DOI: 10.1007/s12055-001-0024-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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Cutler C, Giri S, Jeyapalan S, Paniagua D, Viswanathan A, Antin JH. Acute and chronic graft-versus-host disease after allogeneic peripheral-blood stem-cell and bone marrow transplantation: a meta-analysis. J Clin Oncol 2001; 19:3685-91. [PMID: 11504750 DOI: 10.1200/jco.2001.19.16.3685] [Citation(s) in RCA: 298] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
PURPOSE Controversy exists as to whether the incidence of graft-versus-host disease (GVHD) is increased after peripheral-blood stem-cell transplantation (PBSCT) when compared with bone marrow transplantation (BMT). We performed a meta-analysis of all trials comparing the incidence of acute and chronic GVHD after PBSCT and BMT reported as of June, 2000. Secondary analyses examined relapse rates after the two procedures. METHODS An extensive MEDLINE search of the literature was undertaken. Primary authors were contacted for clarification and completion of missing information. A review of cited references was also undertaken. Sixteen studies (five randomized controlled trials and 11 cohort studies) were included in this analysis. Data was extracted by two pairs of reviewers and analyzed for the outcomes of interest. Meta-analyses, regression analyses, and assessments of publication bias were performed. RESULTS Using a random effects model, the pooled relative risk (RR) for acute GVHD after PBSCT was 1.16 (95% confidence interval [CI], 1.04 to 1.28; P=.006) when compared with traditional BMT. The pooled RR for chronic GVHD after PBSCT was 1.53 (95% CI, 1.25 to 1.88; P <.001) when compared with BMT. The RR of developing clinically extensive chronic GVHD was 1.66 (95% CI, 1.35 to 2.05; P <.001). The excess risk of chronic GVHD was explained by differences in the T-cell dose delivered with the graft in a meta-regression model that did not reach statistical significance. There was a trend towards a decrease in the rate of relapse after PBSCT (RR = 0.81; 95% CI, 0.62 to 1.05). CONCLUSION Both acute and chronic GVHD are more common after PBSCT than BMT, and this may be associated with lower rates of malignant relapse. The magnitude of the transfused T-cell load may explain the differences in chronic GVHD risk.
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Abstract
When an elongating RNA polymerase encounters DNA damage on the template strand of a transcribed gene it can either be arrested by or be transcribed through the lesion. Lesions that arrest RNA polymerases are thought to be subject to transcription-coupled repair, whereas that damage that is bypassed can cause miscoding, resulting in "mutations" in the transcript (transcriptional mutagenesis). We have developed a technique using a plasmid-based luciferase reporter assay to determine the extent to which a particular type of DNA base modification is capable of causing transcriptional mutagenesis in vivo. The system uses Escherichia coli strains with different DNA repair backgrounds and is designed to detect phenotypic changes caused by transcriptional mutagenesis under nongrowth conditions. In addition, this method is capable of indicating the extent to which a particular DNA repair enzyme (or pathway) suppresses the occurrence of transcriptional mutagenesis. Thus, this technique provides a tool with which the effects of various genes on non-replication-dependent pathways resulting in the generation of mutant proteins can be gauged.
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