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71.
72.
Multispectral analysis of magnetic resonance images 总被引:1,自引:0,他引:1
Magnetic resonance (MR) imaging systems produce spatial distribution estimates of proton density, relaxation time, and flow, in a two dimensional matrix form that is analogous to that of the image data obtained from multispectral imaging satellites. Advanced NASA satellite image processing offers sophisticated multispectral analysis of MR images. Spin echo and inversion recovery pulse sequence images were entered in a digital format compatible with satellite images and accurately registered pixel by pixel. Signatures of each tissue class were automatically determined using both supervised and unsupervised classification. Overall tissue classification was obtained in the form of a theme map. In MR images of the brain, for example, the classes included CSF, gray matter, white matter, subcutaneous fat, muscle, and bone. These methods provide an efficient means of identifying subtle relationships in a multi-image MR study. 相似文献
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A medical oncologist’s approach to immunotherapy for advanced renal tumors: Is nephrectomy indicated? 总被引:1,自引:0,他引:1
Metastatic renal cell carcinoma is highly resistant to systemic therapy. Although interleukin-2 and interferon remain the
most active agents for this disease, long-term survival rates remain poor. Two phase 3 trials, European Organization Research
and Treatment of Cancer 30947 and Southwest Oncology Group 8949, have demonstrated a survival benefit of nephrectomy followed
by interferon versus interferon alone in patients having an excellent performance status (PS 0 and 1). Removal of the primary
tumor followed by interferon is not recommended for patients with a moderate or poor PS (PS 2–4). Even with this aggressive
approach, most patients eventually will die from their kidney cancer; therefore, every patient with metastatic disease should
be considered for enrollment into clinical trials. 相似文献
76.
Gene expression profiling of renal medullary carcinoma: potential clinical relevance 总被引:1,自引:0,他引:1
Yang XJ Sugimura J Tretiakova MS Furge K Zagaja G Sokoloff M Pins M Bergan R Grignon DJ Stadler WM Vogelzang NJ Teh BT 《Cancer》2004,100(5):976-985
BACKGROUND: Renal medullary carcinoma is a rare kidney tumor with highly aggressive behavior. This tumor occurs exclusively in young patients with sickle cell trait or disease. To the authors' knowledge, very little is known to date regarding the underlying molecular genetics of this tumor, and no effective therapy has been established. METHODS: The authors analyzed the gene expression profiles of 2 renal medullary carcinomas from patients with sickle cell trait using microarrays containing 21,632 cyclic DNA (cDNA) clones and compared them with the gene expression profiles of 64 renal tumors. RESULTS: Based on global gene clustering with 3583 selected cDNAs, the authors found a distinct molecular signature of renal medullary carcinoma, which clustered closely with urothelial (transitional cell) carcinoma of the renal pelvis, rather than renal cell carcinoma (RCC). This finding of a significant difference in the gene expression patterns of renal medullary carcinoma compared with RCC suggests that this tumor should not be treated as a conventional RCC but, rather, as a special malignancy. This study also identified genes/proteins that may serve as biomarkers for renal medullary carcinoma or as potential targets of novel therapies. In addition, comparative genomic microarray analysis allowed the authors to predict the lack of chromosomal imbalances in this tumor. CONCLUSIONS: To the authors' knowledge, the current study is the first molecular profiling of renal medullary carcinoma, a rare but highly aggressive kidney carcinoma. The genes that are expressed specifically in this tumor may lead to not only a better understanding of its molecular pathways and discoveries of novel diagnostic markers but also, more important, to effective therapeutic interventions. 相似文献
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Ryu RK Omary RA Sichlau MJ Siddiqi A Chrisman HB Nemcek AA Vogelzang RL 《Cardiovascular and interventional radiology》2003,26(4):375-378
When compared in a uterine artery embolization
(UAE) animal model, Embospheres (ES) (Biosphere Medical, Rockland, MA)
were found to induce less uterine ischemia than polyvinyl alcohol (PVA)
particles. Given this finding, we aimed to test the hypothesis that ES
is associated with less pain after UAE than PVA in human patients. We
performed retrospective analysis on data from 72 consecutive UAE
patients, collected from a prospectively acquired database.
Patient-controlled analgesia (PCA) pump-delivered morphine sulfate (MS)
dosages were compared between patients who received ES versus PVA.
Subjective pain scores (SPS) were also compared between the two groups.
Secondary outcome measures, including embolic volume and clinical
outcome data, were also collected. Linear regression and t-test
statistical analyses were performed. Null hypotheses were rejected at
the p < 0.05 level. Mean follow-up period in the PVA
population was 178 days (range 28–426), versus 96 days (range 24–197)
in the ES population. The mean MS doses used by ES and PVA patients
were 37.2 (s.d. 23.5) versus 47.1 (s.d. 26.8), respectively. This
difference was not significant (p > 0.15).
Utilizing a standard 0–10 pain scale, the mean peak SPS for the ES and PVA groups were 5.58 (s.d. 2.77) and 5.07 (s.d. 2.99), respectively.
The difference was not significant. The mean amount of embolic material
used in each ES and PVA patient was 4.86 cc (s.d. 3.01) and 3.52 cc
(s.d. 1.63), respectively. The difference revealed a strong trend
toward statistical significance (p = 0.05). There was one treatment failure in each group of patients. Within both patient
samples, no significant correlation was found when comparing the volume
of embolic used and subsequent MS dose. Despite a strong trend toward a
significantly higher volume of ES used per patient, there is no
subjective or objective difference in pain after UAE with ES when
compared to PVA. 相似文献
80.
Miller DL Balter S Cole PE Lu HT Berenstein A Albert R Schueler BA Georgia JD Noonan PT Russell EJ Malisch TW Vogelzang RL Geisinger M Cardella JF George JS Miller GL Anderson J 《Journal of vascular and interventional radiology : JVIR》2003,14(8):977-990
PURPOSE: To determine peak skin dose (PSD), a measure of the likelihood of radiation-induced skin effects, for a variety of common interventional radiology and interventional neuroradiology procedures, and to identify procedures associated with a PSD greater than 2 Gy. MATERIALS AND METHODS: An observational study was conducted at seven academic medical centers in the United States. Sites prospectively contributed demographic and radiation dose data for subjects undergoing 21 specific procedures in a fluoroscopic suite equipped with built-in dosimetry capability. Comprehensive physics evaluations and periodic consistency checks were performed on each unit to verify the stability and consistency of the dosimeter. Seven of 12 fluoroscopic suites in the study were equipped with skin dose mapping software. RESULTS: Over a 3-year period, skin dose data were recorded for 800 instances of 21 interventional radiology procedures. Wide variation in PSD was observed for different instances of the same procedure. Some instances of each procedure we studied resulted in a PSD greater than 2 Gy, except for nephrostomy, pulmonary angiography, and inferior vena cava filter placement. Some instances of transjugular intrahepatic portosystemic shunt (TIPS) creation, renal/visceral angioplasty, and angiographic diagnosis and therapy of gastrointestinal hemorrhage produced PSDs greater than 3 Gy. Some instances of hepatic chemoembolization, other tumor embolization, and neuroembolization procedures in the head and spine produced PSDs greater than 5 Gy. In a subset of 709 instances of higher-dose procedures, there was good overall correlation between PSD and cumulative dose (r = 0.86; P <.000001) and between PSD and dose-area-product (r = 0.85, P <.000001), but there was wide variation in these relationships for individual instances. CONCLUSIONS: There are substantial variations in PSD among instances of the same procedure and among different procedure types. Most of the procedures observed may produce a PSD sufficient to cause deterministic effects in skin. It is suggested that dose data be recorded routinely for TIPS creation, angioplasty in the abdomen or pelvis, all embolization procedures, and especially for head and spine embolization procedures. Measurement or estimation of PSD is the best method for determining the likelihood of radiation-induced skin effects. Skin dose mapping is preferable to a single-point measurement of PSD. 相似文献