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Laryngoscopic images of the vocal tract are used for diagnostic purposes. Quantitative mea-surements like changes of the glottis size or the surface of the vocal cords during an image sequence can be helpful to describe the healing process or to compare the findings of diffe-rent patients. Typically the endoscopic images are circulary symmetric distorted (barrel di-stortion). Therefore measurements of geometric dimensions depend on the object´s position in the image. In this paper an algorithm is presented which allows the computation of the translational invariant "real" object size by correcting the image distortion without using additional calibration of the optical environment.
Background
Breast reconstruction is an important coping tool for patients undergoing a mastectomy. There are numerous surgical techniques in breast reconstruction surgery (BRS). Regardless of the technique used, creating a symmetric outcome is crucial for patients and plastic surgeons. Three-dimensional surface imaging enables surgeons and patients to assess the outcome’s symmetry in BRS. To discriminate between autologous and alloplastic techniques, we analyzed both techniques using objective optical computerized symmetry analysis. Software was developed that enables clinicians to assess optical breast symmetry using three-dimensional surface imaging.
Methods
Twenty-seven patients who had undergone autologous (n = 12) or alloplastic (n = 15) BRS received three-dimensional surface imaging. Anthropomorphic data were collected digitally using semiautomatic measurements and automatic measurements. Automatic measurements were taken using the newly developed software. To quantify symmetry, a Symmetry Index is proposed.
Results
Statistical analysis revealed that there is no dif- ference in the outcome symmetry between the two groups (t test for independent samples; p = 0.48, two-tailed).
Conclusion
This study’s findings provide a foundation for qualitative symmetry assessment in BRS using automatized digital anthropometry. In the present trial, no difference in the outcomes’ optical symmetry was detected between autologous and alloplastic approaches.
Objective:
Complex hue/saturation images as a new approach for color texture classification using Gabor filters are introduced and compared with common techniques.
Method:
The interpretation of hue and saturationas polar coordinates allows direct use of the HSV-colorspace for Fourier transform. This technique is applied for Gabor feature extraction of color textures. In contrast to other color features based on the RGB-colorspace [1] the combination of color bands is done previous to the filtering.
Results:
The performance of the new HS-featuresis compared with that of RGB based as well as grayscale Gabor features by evaluating the classifi-cation of 30 natural textures. The new HS-featuresshow same results like the best RGB features but allow a more compact representation. On the averagethe color features improve the results of grayscale features.
Conclusion:
The consideration of the color information enhances the classification of color texture. The choice of colorspace cannot be adjudged finally, but the introduced features suggest the use of the HSV-colorspace with less features than RGB.
Objectives
Tumor size is a well recognized prognostic factor in early stage cervical carcinoma (CX). However, limited knowledge exists about the value of tumor size in surgically treated CX with extrauterine extension.
Methods
245 cases of local advanced CX (FIGO stage IIA and IIB) who received upfront surgery were evaluated regarding tumor size, regarding the prediction of pelvic lymph node involvement and recurrence free and overall survival during a median follow-up time of 54 months (95% CI 45.4–62.6 months). Tumors larger than 4 cm were defined as bulky stage disease.
Results
Bulky disease was seen in 46.1% (113/245). 60.2% of these patients showed pelvic lymph node involvement, compared to 42.4% (56/132) in non-bulky tumors (p = 0.006; odds ratio: 2.2 [95% CI: 1.3–3.6]). Patients with bulky tumors showed an increase of recurrent disease (40.2% vs. 28.0%; p = 0.045). The relative risk for recurrent disease was 1.97 (95% CI: 1.3–3.0). The 5-year overall survival rate was significantly lower (67.7% [95% CI: 58.2–74.8] vs. 49.5% [95% CI: 36.8–59.1]; p = 0.0015). In multivariate analysis, tumor stage, pelvic lymph node involvement and maximal tumor size were independent prognostic factors.
Conclusions
The results suggest that tumor size, defining bulky disease as tumors larger than 4 cm, is of prognostic impact also in FIGO stage II cervical carcinomas. A revised FIGO/TNM classification system similar to the subgrouping of stage IB CX is recommended for stage II using a cut-off value of 4 cm as discriminator: stage IIA1 and stage IIB1 for tumors with ≤ 4 cm and IIA2 and IIB2 for tumors > 4 cm (i.e. bulky disease).
Objectives: Different patterns of invasion (representing different grades of tumor cell dissociation) are associated with prognostic outcome in cancer. We evaluated the prognostic value of different patterns of invasion (PI) in cervical carcinomas (CX).
Methods: Six hundred eleven surgically treated CX (FIGO IB to IIB) were re-evaluated histologically regarding the PI, using a three-level scoring system. Closed PI was defined as cohesive growth with well-delineated (pushing) borders. In finger-like PI the tumor grows in solid cords/trabecles. Highly dissociative growth in small groups or single cells was defined as spray-like PI. Types of PI were correlated to tumor stage, histo-morphologic factors and prognostic outcome.
Results: Sixty percent of the tumors showed a spray-like PI, 30% a finger-like PI and only 7.4% were of the closed type. Spray-like PI showed a significant correlation with advanced stage disease, lymphovascular space involvement, poorly differentiated tumors and pelvic lymph node metastases. Spray-like PI was accompanied by a reduced 5-year overall survival when compared to the finger-like and closed PI (68.7% vs. 80.9% vs. 88.5%; P=0.0004). The prognostic impact of the PI disappeared in node-positive patients (P=0.06) but persisted in patients without pelvic lymph node disease (P=0.03). In multivariate analysis, using COX regression model, the PI represented as independent prognostic factor.
Conclusions: Spray-like PI (i.e., highest degree of tumor cell dissociation) is associated with advanced tumor stages, increased rate of recurrency and a reduced overall survival. In separate analysis of patients with and without lymph node metastases, the impact of PI persisted only in node-negative cases as a prognostic factor.
Several kinds of cellular adhesion molecules, like different splicing variants of CD 44, have gained important as prognostic or markers for metastatic disease. Fresh frozen samples from 64 cervical carcinoma (CX) were stored in liquid nitrogen and examined using ELISA-technique, testing the prognostic impact. Normal cervical tissue served as control. CD 44-v6 concentration, was significant elevated in tumor tissue, when compared to the controls (P=0.04). There was no correlation to tumor stage (P=0.61), lymphovascular space involvement (P=0.075) or pelvic lymph node involvement (P=0.81). The CD 44-v6 concentration was not informative regarding recurrence-free and overall survival. Contrary to immunohistochemistry, the quantification of CD 44-v6 using ELISA-technique does not provide any further information.
Objective: To determine the utility of DNA content and DNA-related variables of proliferative activity regarding prognosis in cervical cancer.
Study design: DNA image (ICM) andflow cytometry (FCM) were performed to determine the DNA index (DI), 5c-exceeding rate (5c-ER), S-phase fraction (SPF) and proliferation index (PI) in 163 patients with surgically staged pT1b1-pT2b squamous cell cancer of the uterine cervix and treated with primary radical hysterectomy. ICM was performed on imprint cytology, obtained from fresh tumor tissue, which was also used for FCM. Results were analyzed using the chi2 test and Cox regression analysis for risk of pelvic lymph node involvement, tumor recurrence and recurrence-free survival (RFS).
Results: ICM was performed on all 163 and FCM on 133 samples. One-third of the tumors showed DNA aneuploidy. Analysis demonstrated prognostic significance of a DI > or = 1.70, with a (70:30) 2.3-fold risk of recurrence (P=.024) and reduced RFS of 10 months (P=.003) in cases of DI > or = 1.70. A high 5c-ER > 11% was associated with pelvic lymph node involvement and decreased RFS (P < or = .04). Significantly more relapses were found in tumors with SPF > 12% (70.8% vs. 29.2%, P=.007). RFS was markedly reduced in tumors with high SPF (52.3 vs. 61.1 months, P=.011). Low proliferative tumors (PI<25%) were associated with lower stage (P=.036) and increased RFS (61.2 vs. 47.1 months, P=.028). In multivariate analysis of clinicopathologic variables (pT category, nodal status, lymphovascular space involvement) and DNA related variables, pelvic lymph node involvement was the only significant predictor of RFS. In patients with nodal involvement, tumors with DI >1.70 were associated with lessfavorable outcomes.
Conclusion: DNA-related variables of cell cycle analysis were valuablefor predicting prognosis in cervical cancer patients. Tumors with DI>1.70, 5c-ER >11% and high proliferative activity (SPF>12%, PI>25%) represent a subgroup with a poor prognosis.
Recent developments in lasers have provided us the possibility of laser ocular surgery. The xenon, argon, neodymium:YAG and dye lasers have been successfully used in out-patient clinics. The excimer laser has been attracting researchers' interest in the new application of laser to cornea and lens. The erbium:YAG laser emits a 2.94-microns beam that can ablate the transparent ocular tissues such as lenses and corneas. The author has applied this laser to the cornea, lens, vitreous and other ocular tissues. The erbium:YAG laser beam was directed through a 1.5-meter-long, 200-microns-diameter fiberoptic guide. The radiant energy measured about 50 mJ at the end of the probe. The laser was emitted as a 400-microsecond pulse. Freshly enucleated rabbit eyes were used in this study. Laser burns were applied to the tissue surface at various energy settings. At minimal power, the tissues were coagulated by the erbium:YAG laser application. At a power of more than 636-954 mJ/mm2, tissue began to evaporate; the tissue loss was observed under a surgical light microscope. Corneal photoablation, lens ablation, iridotomy, trabeculotomy, cutting of the vitreous and retinal ablation were easily performed. Like the excimer laser, the erbium:YAG laser is a potential tool for ocular surgery.