螺旋CT图像噪声的评价

目的 :评价螺旋CT中内插方式、螺距以及重建间隔对噪声的影响。方法 :采用SomatomPlus 4螺旋CT机。在相同条件下扫描直径为 2 0cm的水模 ,测得水模图像中心 40cm2 兴趣区的CT值标准差作为评价噪声水平的指标。结果 :3 60°线性内插的噪声减少 (t =3 4.87,P <0 .0 0 1) ,180°线性内插的噪声增加 (t =18.78,P <0 .0 0 1)。螺距大于 1.0或小于 1.0与螺距为 1.0时噪声水平的差异无显著性意义 (P >0 .0 5 )。随着重建间隔改变 ,相应噪声水平的差异无显著性意义 (P >0 .0 5 )。结论 :与常规扫描相比 ,螺旋CT内插方式对噪声有一定影响 ,而螺距与重建间隔对噪声水平影响不明显。     

Iopamidol arteriography: discomfort and pain

A double-blind, randomized study was performed to compare discomfort and pain associated with the use of iopamidol and Hypaque (diatrizoate sodium and diatrizoate meglumine) during iliofemoral runoff arteriography in 33 patients. Iopamidol caused substantially less discomfort and pain. The evaluation was helped by audiotaping the study and comparing patients' vocal responses to injections of these materials.     

BD focalpoint slide profiler performance with atypical glandular cells on SurePath Papanicolaou smears

BACKGROUND:

The FocalPoint Slide Profiler is an automated cervical cytology screening system that is approved for primary screening. It identifies up to 25% of slides as requiring No Further Review. However, few studies have evaluated FocalPoint performance with glandular abnormalities.

METHODS:

Sixty‐six SurePath Papanicolaou (Pap) tests with a diagnosis of atypical glandular cells were identified. A total of 172 Pap tests with a diagnosis of “endometrial cells present” were included as controls. Follow‐up histology was abnormal if diagnosed as high‐grade squamous intraepithelial lesions, adenocarcinoma in situ, carcinoma, or complex endometrial hyperplasia. The FocalPoint software ranked each case into 1 of 7 categories: quintiles 1 (high risk) through 5 (low risk), No Further Review, and Process Review.

RESULTS:

A total of 215 slides were qualified for review; 38 (57.6%) atypical glandular cells cases were abnormal on follow‐up biopsy, and 27 (71.1%) atypical glandular cells with abnormal follow‐up qualified for review; no cases were classified No Further Review, and 9 (33%) were ranked in quintile 1. Twenty‐three (82.1%) atypical glandular cells with benign follow‐up were qualified for review; 3 (11%) cases were classified No Further Review, and 4 (17%) were ranked in quintile 1. There was a statistically significant difference between the ranking of benign atypical glandular cells cases, abnormal atypical glandular cells cases, and control cases (P = .03). However, when collapsed into No Further Review versus all other quintiles, the differences were not significant (P = .20).

CONCLUSIONS:

The FocalPoint Slide Profiler did not classify glandular lesions with abnormal follow‐up in the No Further Review category. However, these cases were not preferentially ranked in quintile 1. FocalPoint‐screened slides need to be carefully reviewed for glandular abnormalities, regardless of the quintile ranking. Cancer (Cancer Cytopathol) 2010. © 2010 American Cancer Society.     

Porokeratosis Causing Change in Melanocytic Nevi

Large cell transformation of mycosis fungoides (MF) is an uncommon phenomenon. We present a case of CD30‐positive large cell transformation and discuss its possible pathophysiology. A 74 year‐old male with a 36‐year history of patch stage MF presented with a 3‐month history of right chest cellulitis that was refractory to IV antibiotic treatment. Skin biopsies from his thigh demonstrated a patchy dermal infiltrate of irregular and hyperchromatic lymphocytes and epidermotropism. The majority of the infiltrate was positive for CD4, CD3, CD2, and negative for CD7. Only 10% were positive for CD25 and CD8. Biopsies obtained from the ulcerated chest nodules showed a dermal infiltrate of large and pleomorphic lymphoid cells with prominent nucleoli. These large lymphoid cells were strongly positive for CD3, CD30, CD25, CD2 and UCHL‐1. Occasional cells were positive for CD4 and CD20. They were negative for ALK‐1, TIA‐1, CD7, CD8, and CD15. T‐gamma receptor gene rearrangement analyses by polymerase chain reaction demonstrated a clonal process with similar rearrangement patterns identified in the patch stage MF as well as in large cell transformation areas. Examinations of his peripheral blood and bone marrow were negative. The patient had tolerated one cycle of CHOP chemotherapy.     

Detection of mRNA encoding calcitonin, calcitonin gene related peptide and proopiomelanocortin in human tumors

Expression of the calcitonin (CT)/calcitonin gene related peptide (CGRP) gene and the proopiomelanocortin (POMC) gene has been demonstrated by Northern blot hybridization analysis of RNA extracted from human medullary thyroid carcinoma (MTC), pheochromocytoma and lung carcinoma. CT mRNA in these tumors could not be distinguished in size from CT mRNA isolated from normal human thyroid tissue. CGRP mRNA (previously demonstrated in 12 out of 12 lung tumor cell lines investigated) could not be detected in 13 primary lung tumors or 10 metastases thereof. The length of POMC mRNA in MTCs (present in all 4 metastases investigated but not in 7 primary tumors) and pheochromocytomas is about 100 nucleotides more than pituitary POMC RNA. In lung tumors 2 POMC RNA species can be detected, one of the same size as in pituitary tissue and one about 100 nucleotides larger.     

In vivo NMR diffusion spectroscopy: 31P application to phosphorus metabolites in muscle

Apparent diffusion coefficients (Da) of individual metabolites can be studied in vivo by diffusion NMR spectroscopy using an echo sequence sensitized to molecular motion. The methods are based on the echo attenuation due to phase dispersion resulting from incoherent displacement during the diffusion time. As the displacement of metabolites by diffusion in vivo can be affected by compartment size, temperature, adsorption processes, etc., the presented methods are potentially useful in studying such phenomena in vivo. Here, the methods are applied to phosphocreatine in the rat quadriceps muscle. It is demonstrated that the displacement of phosphocreatine resembles free diffusion for short diffusion times but becomes limited as a result of boundaries due to compartmentation for longer diffusion times. The limit of the displacement indicates an apparent average size of 44 microns of the compartment in the direction of the diffusion gradient. As the gradient was applied approximately parallel (angle less than 25 degrees) to the muscle fiber, this result indicates that phosphocreatine moves freely in the cytosol but is limited by the boundaries of the muscle cells. Error analyses are performed with regard to motion artifacts and gradient performance. The methods were tested extensively for distilled water and free metabolites.     

Improvement in the routine screening performance of cytotechnologists over time

BACKGROUND:

Documenting the performance of gynecologic screening in actual practice settings is difficult to achieve. In the current study, the screening performance of 11 individual cytotechnologists as well as that of the overall laboratory over 2 consecutive time periods was examined using the rapid prescreening (RPS) method.

METHODS:

RPS was performed by all cytotechnologists in a single laboratory over 2 separate 8‐month periods. The sensitivity of screening for individual and groups of cytotechnologists was examined. For purposes of comparison, cytotechnologists were divided into 2 groups: screeners with an overall routine sensitivity ≥95% and screeners with an overall sensitivity <95%.

RESULTS:

Atypical squamous cells (ASC) were used as a threshold, and routine screening sensitivity was found to vary from 68.3% to 96.8%. The overall sensitivity of the laboratory for RPS and routine screening was 43.6% and 88.4%, respectively. Over time, the overall laboratory sensitivity of routine screening improved from 85.3% to 91.3% (P = .01). During this same time frame, the sensitivity of the screeners with an overall sensitivity <95% improved from 79.3% to 91.2% (P < .001), whereas the sensitivity of screeners with an overall routine sensitivity ≥95% remained the same (96.1% to 96.4%; P = .6).

CONCLUSIONS:

In addition to improved overall performance of the laboratory by detecting and correcting errors, the results of the current study indicate that using RPS consistently over time might play a role leading to improved performance of cytotechnologists with an overall routine sensitivity <95% but not of cytotechnologists with an overall routine sensitivity ≥95%. Cancer (Cancer Cytopathol) 2009. © 2009 American Cancer Society.     

螺旋CT三维成像术-SSD的应用

目的：对三维成像技术SSD的临床应用进行探讨。材料与方法：开展SSD病人20例，其中男13例，女7例，年龄24－69岁，采用西门子Balance CT机，进行容积扫功，层厚2mm-4mm，螺距1－2，三维重建图像后处理采用SSD并采取多个角度观察，分析。结果：20例SSD检查成像良好。结论：SSD是非创伤性影像检查，具有安全、简便、价廉的优点，是一种适合临床广泛应用的影像检查方法。