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51.
Validating three-dimensional imaging of the breast   总被引:3,自引:0,他引:3  
Losken A  Seify H  Denson DD  Paredes AA  Carlson GW 《Annals of plastic surgery》2005,54(5):471-6; discussion 477-8
The potential to extrapolate accurate data from 3-dimensional (3D) images of the breast is enormous and will greatly improve our ability to qualitatively determine differences in shape, size, and contour. The validity of these calculated measurements is important and needs to be determined before any meaningful data can be evaluated. PART I: Premastectomy 3D images (3dMD patient) were obtained on 19 breasts (14 patients). The volume of the mastectomy specimen was determined intraoperatively using water displacement. Two independent raters then calculated breast volumes using the 3D images and software, and these were compared with the intraoperative volume. Inter- and intrarater reliability was determined. Part II: Surface measurements (nipple to notch) were then evaluated on 20 breasts (10 patients) by comparing the 3D image determined distance to the known measurements. PART I: The average breast volume was 500 mL, compared with 489 mL for rater 1 and 490 mL for rater 2. The relative difference between the measured volume and the calculated volume for rater 1 and rater 2 was about -2%, with a standard deviation of +/- 13% to 16%. The coefficient of reproducibility for each reader was excellent, at 0.80 for rater 1 and 0.92 for rater 2. The level of agreement between the readers was also high at 0.975. Part II: The average nipple to notch measurement for each patient was 27.1 cm, compared the calculated average of 25.1 cm for rater 1 and 26.1 cm for rater 2. The mean relative difference between the measured and calculated distances for raters 1 and 2 was about -6%, with a standard deviation of +/- 6% to 7%. The level of agreement between readers was high, at 0.975. The ability to objectively determine breast volume and surface measurements using 3D imaging technology is now available with consistent and reproducible accuracy. Measurements are typically underestimated, with more variability when calculating volumes. Although inherent subjectivity will always exist when evaluating breast measurements, 3D technology provides invaluable information, particularly in the longitudinal evaluation of results.  相似文献   
52.
Objective In spite of the recent interest in endoscopic third ventriculostomy, ventriculoperitoneal (VP) shunt is still the gold standard in treating non-obstructive hydrocephalus in children. The peritoneal cavity remains the optimal site for cerebrospinal fluid (CSF) diversion. Shunt insertion and re-interventions carry a high risk of inaesthetic abdominal scars and long-term morbidity. We report a technique of transumbilical shunt insertion, which provides better cosmetic results and without many more complications. This approach has been performed for a long period in a wide variety of intra-abdominal conditions by pediatric surgeons.Methods Between March and October 2003, we inserted 12 VP shunts in children. For eight consecutively treated children the follow-up is more than 3 months. All the shunts were inserted through the umbilicus. These eight children are the subjects of this study. Indications for shunting were: communicating hydrocephalus (6 cases), subdural hematoma (1 case), and hygroma associated with an arachnoid cyst (1 case). The population consisted of 7 boys and 1 girl, ranging in age between 6 weeks and 47 months (mean age: 15 months), and their body weights varied between 2,110 g and 18,000 g (mean weight: 8,470 g). All children were examined twice a day for 3 days, and wounds were examined daily to check for the absence of sepsis or dehiscence. Clinical controls were performed 1 month after discharge. The operating surgeon was invited to comment on any difficulties encountered in making or closing this incision afterwards.Results The average length of clinical follow-up was 6 months (range 4–7 months). One infection of the VP shunt occurred. It was treated with external drainage and antibiotics. After 1 week, a second VP shunt was inserted using the same technique without particular difficulty and with a nice cosmetic result. Concerning the seven other children, the cosmetic results were optimal, with no puckered abdominal scars or wound dehiscence, and with no perioperative or long-term complications related to the umbilical approach.Conclusion At this early follow-up, umbilical incision for shunt insertion is a safe and easy technique. It provides an optimal cosmetic result, even in cases of re-intervention. This minimally invasive surgery does not require long specialized training. We have not shown an increase in complications associated with a learning curve. Longer follow-up is needed to evaluate the risk of infection.  相似文献   
53.
Poroid hidradenoma is a recently described variant of eccrine poroma. This neoplasm presents structural findings of hidradenoma (solid and cystic areas) and cytological characteristics of poromas (poroid and cuticular cells, the latter showing ductal differentiation). We present a case of poroid hidradenoma in a 74-year-old woman, who consulted her physician because of a nodular lesion on the left buttock.  相似文献   
54.
HIV-1-infected patients with osteoporosis were randomly assigned to alendronate 70 mg once-weekly plus dietary counselling (n = 11) or diet counselling alone (n = 14). At week 96, 27% of patients on alendronate versus 96% of controls presented with osteoporosis. Spine bone mineral density (BMD) increases were detected at week 48, and progressed thereafter. Improvements in trochanter BMD were obtained after 2 years. Once-weekly oral alendronate may be an effective and safe treatment for HIV-1-associated osteoporosis.  相似文献   
55.
RATIONALE AND OBJECTIVES: To simplify the diagnostic features used by an artificial neural network compared with logistic regression (LR) in the diagnosis of calvarial metastasis with computed tomography and analyze their accuracy. MATERIALS AND METHODS: Twenty-one of 167 patients with calvarial lesions were found to have metastasis. Clinical and computed tomography data were used for LR and neural network models. Both models were tested with the leave-one-out method. The final results of each model were compared using the area under receiver operating characteristic curve (Az). RESULTS: The neural network identified metastasis significantly more successfully than LR with an Az of 0.9324 +/- 0.0386 versus 0.9192 +/- 0.0373, P = .01. The most important features selected by the LR and neural network were age and edge definition. CONCLUSION: Neural networks offer wide possibilities over statistics for the study of calvarial metastases other than their minimum clinical and radiologic features for diagnosis.  相似文献   
56.
A 56 year old man with fever and lumbar pain who underwent an abdominal CT scan that showed lumbar arthrosic changes, although it was not possible to rule out infectious disease in L5/S1. Bone scintigraphy was requested. It showed heterogeneous hyperuptake that did not make it possible to exclude a spondylodiscitis in this site. Scintigraphy with 67Ga-citrate excluded infectious diseases in the lumbar spine column. However, a pathological uptake was observed in the left iliac fossa suggestive of psoas abscess, which was confirmed by ultrasonography, isolating streptococcus viridans.  相似文献   
57.
58.
P-cadherin expression in breast carcinomas has been associated with tumors of high histologic grade and lacking estrogen receptor-alpha, suggesting a link between these proteins. In the MCF-7/AZ breast cancer cell line, blocking estrogen receptor-alpha signaling with the antiestrogen ICI 182,780 induced an increase of P-cadherin, which coincided with induction of in vitro invasion. Retroviral transduction of MCF-7/AZ cells, as well as HEK 293T cells, showed the proinvasive activity of P-cadherin, which requires the juxtamembrane domain of its cytoplasmic tail. This study establishes a direct link between P-cadherin expression and the lack of estrogen receptor-alpha signaling in breast cancer cells and suggests a role for P-cadherin in invasion, through its interaction with proteins bound to the juxtamembrane domain.  相似文献   
59.
OBJECTIVE: To compare the incidence of diplopia after topical or regional injection anesthesia in cataract surgery. STUDY DESIGN: Retrospective, noncomparative interventional case series. PARTICIPANTS AND METHODS: Three thousand five hundred forty-two consecutive cataract surgeries, performed from March 1998 to December 2001, were studied. MAIN OUTCOME MEASURES: Incidence and mechanisms of diplopia. RESULTS: Two thousand one hundred twenty-two patients were operated under regional and 1420 under topical anesthesia. Twenty-four cases of diplopia were observed, 21 (87.5%) in the regional group and 3 (12.5%) after topical anesthesia (P = 0.005). Eleven cases (45.8%) were secondary to motility problems, all in the regional anesthesia group (P = 0.006). Eight cases (33.3%) were secondary to refractive errors or intraocular lens luxation, 5 after regional and 3 after topical anesthesia (P = 0.88). Five cases (20.8%) were secondary to fusion loss, all in the regional anesthesia group (P = 0.06). CONCLUSIONS: In our study, topical anesthesia was associated with a lower incidence of diplopia relative to regional injection anesthesia. No cases of diplopia secondary to fusion loss or muscle damage were found after topical anesthesia surgery.  相似文献   
60.
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