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AIM: To investigate whether narrow band imaging (NBI) is a useful tool for the in vivo detection of angiogenesis in inflammatory bowel disease (IBD) patients. METHODS: Conventional and NBI colonoscopy was performed in 14 patients with colonic inflammation (8 ulcerative colitis and 6 Crohn’s disease). Biopsy samples were taken and CD31 expression was assayed immuno- histochemically; microvascular density was assessed by vessel count. RESULTS: In areas that were endoscopically normal but positive on NBI, ther...  相似文献   
23.
The present investigation evaluates the effectiveness of NaF treatment in modifying the natural course of subclinical otosclerosis, as monitored by the stapedius reflex. The study was carried out on 128 relatives of patients suffering from surgically confirmed footplate otosclerosis. The diagnosis of subclinical otosclerosis was made on the basis of presence of the on-off effect. One group of subjects was treated with NaF in doses ranging from 6 to 16 mg according to age. The treatment lasted 2 years. A second group served as a control. Changes in stapedius reflex morphology were evaluated at 1, 2, and 5 years from the onset of treatment. The investigation demonstrated that NaF has a stabilizing effect on early otosclerosis. This drug, in fact, arrests the disease process in more than 60 percent of ears at the 2-year follow-up and in more than 50 percent at 5 years. A program of secondary prevention of otosclerosis by NaF is suggested.  相似文献   
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Skin-sparing benefits derived from the use of megavoltage photon beams can be strongly reduced when filters are inserted between the source and the patient. The use of plastic masks for immobilizing the patient is the most important cause of this reduction in head and neck treatments. The influence of thermoplastics, commercially available for patient immobilization systems (Orfit Raycast (Luxilon Ind. Co.), Posicast (Sinmed bv) and Optimold (WFR Aquaplast Corp.)), on the patient skin dose value has been investigated by using an NE2534 ‘Markus’ chamber. Indicative measurements with moulded masks (carried out with 2-mm Orfit and3.2-mm Optimold layers) show significant differences between masks moulded with the two thermoplastics.  相似文献   
25.
PURPOSE: Investigating the correlation between dosimetric/clinical parameters and late rectal bleeding in patients treated with adjuvant or salvage radiotherapy after radical prostatectomy. METHODS AND MATERIALS: Data of 154 consecutive patients, including three-dimensional treatment planning and dose-volume histograms (DVHs) of the rectum (including filling), were retrospectively analyzed. Twenty-six of 154 patients presenting a (full) rectal volume >100 cc were excluded from the analysis. All patients considered for the analysis (n = 128) were treated at a nominal dose equal to 66.6-70.2 Gy (ICRU dose 68-72.5 Gy; median 70 Gy) with conformal (n = 76) or conventional (n = 52) four-field technique (1.8 Gy/fr). Clinical parameters such as diabetes mellitus, acute rectal bleeding, hypertension, age, and hormonal therapy were considered. Late rectal bleeding was scored using a modified Radiation Therapy Oncology Group scale, and patients experiencing >or=Grade 2 were considered bleeders. Median follow-up was 36 months (range 12-72). Mean and median rectal dose were considered, together with rectal volume and the % fraction of rectum receiving more than 50, 55, 60, and 65 Gy (V50, V55, V60, V65, respectively). Median and quartile values of all parameters were taken as cutoff for statistical analysis. Univariate (log-rank) and multivariate (Cox hazard model) analyses were performed. RESULTS: Fourteen of 128 patients experienced >or=Grade 2 late bleeding (3-year actuarial incidence 10.5%). A significant correlation between a number of cutoff values and late rectal bleeding was found. In particular, a mean dose >or=54 Gy, V50 >or=63%, V55 >or=57%, and V60 >or=50% was highly predictive of late bleeding (p or=63% and those with V50 <63% (DVH grouping), data were fitted with a Cox regression hazard model using DVH grouping, rectal volume, and the main clinical parameters as independent variables. Results of the analysis showed that DVH grouping (relative risk 3.3; p = 0.04) and acute bleeding (relative risk 7.1; p = 0.001) are independently predictive of late bleeding. CONCLUSIONS: DVHs of the rectum are significantly correlated with late bleeding for patients irradiated at 66.6-70.2 Gy after radical prostatectomy.  相似文献   
26.
PURPOSE: To investigate the relationship between rectal bleeding and dosimetric-clinical parameters in patients receiving three-dimensional conformal radiotherapy (3D-CRT) for localized prostate cancer. METHODS: In a retrospective national study (AIROPROS01-01, AIRO: Associazione Italiana Radioterapia Oncologica), planning/clinical data for 245 consecutive patients with stage T1-4N0-x prostate carcinoma who underwent 3D-CRT to 70-78 Gy (ICRU point) were pooled from four Italian institutions. The correlation between late rectal bleeding and rectal dose-volume data (the percentage of rectum receiving more than 50, 55, 60, 65, 70, and 75 Gy [V(50-70)]) and other dosimetric and clinical parameters were investigated in univariate (log-rank) and multivariate (Cox regression model) analyses. Median follow-up was 2 years. RESULTS: Twenty-three patients were scored as late bleeders according to a modified RTOG definition (Grade 2: 16; Grade 3: 7); the actuarial 2-year rate was 9.2%. Excepting V75, all median and third quartile V(50-70) values were found to be significantly correlated with late bleeding at univariate analysis. The smallest p value was seen for V(50) below/above the third quartile value (66%). The V70 (cut-off value: 30%) was found to be also predictive for late bleeding. In the high-dose subgroup (74-78 Gy), Grade 3 bleeding was highly correlated with this constraint. The predictive value of both V(50) and V(70) was confirmed by multivariate analyses. CONCLUSIONS: The present article provides evidence for correlation between rectal DVH parameters and late rectal bleeding in patients treated with curative intent with 3D-CRT. To keep the rate of moderate/severe rectal bleeding below 5-10%, it seems advisable to limit V(50) to 60-65%, V(60) to 45-50%, and V70 to 25-30%.  相似文献   
27.
OBJECTIVE: To describe our experience with the retrosigmoid-transmeatal (RS-TM) approach in auditory brainstem implantation (ABI) as well as the anatomosurgical guidelines for this route. STUDY DESIGN: Retrospective case review. SETTING: Ear, Nose, and Throat Department of the University of Verona. PATIENTS: Five patients with neurofibromatosis type 2 (NF2) were operated on for vestibular schwannoma removal with ABI implantation from April 1997 to June 1999. The patients were four men and one woman, whose ages ranged from 22 to 37 years. The tumor sizes ranged from 12 to 30 mm. The records of a total of 179 patients operated on for vestibular schwannoma (VS) removal via the RS-TM approach from January 1990 to June 1999 were also evaluated. Their ages ranged from 18 to 88 years (average 54 years). The tumor sizes ranged from 4 to 50 mm. Five patients had a solitary VS in the only hearing ear. INTERVENTION: The classic RS-TM approach was used in all patients. After tumor excision, for ABI implantation, the landmarks (seventh, eighth, and ninth cranial nerves, choroid plexus) for the foramen of Luschka were carefully identified. The choroid plexus was then partially removed, and the tela choroidea was divided and bent back. The floor of the lateral recess of the fourth ventricle and the convolution of the dorsal cochlear nucleus became visible. The electrode array was then inserted into the lateral recess and correctly positioned with the aid of electrically evoked auditory brainstem responses (EABRs). MAIN OUTCOME MEASURES: Intraoperative EABR and postoperative speech perception evaluation. RESULTS: Auditory sensations were induced in all patients with various numbers of electrodes. Different pitch sensations could be identified with different electrode stimulation. CONCLUSIONS: In the authors' experience, the RS-TM approach is the route of choice for patients who are candidates for ABI when there is a chance of hearing preservation during surgery. If auditory function is lost during surgery, anatomical preservation of the cochlear nerve may allow hearing restoration with a cochlear implant. Direct intraoperative recording of cochlear nerve action potentials (CNAPs) and round window electrical stimulation are mandatory for these purposes. In addition, decompression of the intrameatal portion of the vestibular schwannoma and planned partial tumor resection with hearing preservation are also possible with the RS-TM approach.  相似文献   
28.
Thirteen individuals with unilateral Menière's disease were chosen for experimental chemical labyrinthectomy. All subjects suffered from frequent attacks of disabling vertigo and had mean pure-tone thresholds greater than 50 dB in the affected ear. The surgical procedure was similar to stapedectomy; after removal of the stapes, several crystals of NaCl were placed in the vestibule which was then covered with a vein graft. Postoperative recovery was rapid, allowing patients to be discharged 4-6 days after surgery. Of the 13 subjects, all reported complete relief from vertigo. Tinnitus was cured in 7 subjects, greatly improved in 4 and unchanged in 2. Most patients complaining of aural fullness preoperatively reported relief from this symptom following surgery. To date (up to 4 years post-surgery) none of the subjects has shown any significant alteration in audiologic or vestibular function in the contralateral ear. The ease and safety of this procedure make it an attractive method when cochleovestibular deafferentation is indicated.  相似文献   
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Background

Salvage radiation therapy (SRT) is a recommended treatment option for biochemical recurrence after radical prostatectomy (RP). However, its effectiveness may be limited to specific categories of patients.

Objective

We aimed to identify the optimal candidates for early SRT after RP.

Design, setting, and participants

The study included 925 node-negative patients treated with SRT after RP at seven institutions. Patients received SRT for either prostate-specific antigen (PSA) rising, or PSA persistence after RP that was defined as PSA level ≥0.1 ng/ml at 1 mo after surgery. All patients received local radiation to the prostate and seminal vesicle bed.

Outcome measurements and statistical analysis

The primary outcome measured was distant metastasis after SRT. Regression tree analysis was used to develop a risk-stratification tool. Multivariable Cox regression analysis and nonparametric curve fitting methods were used to explore the relationship between PSA level at SRT and the probability of metastasis-free survival at 8 yr.

Results and limitations

At a median follow-up of 8.0 yr, 130 patients developed distant metastasis. At multivariable analysis, pre-SRT PSA level was significantly associated with distant metastasis (hazard ratio: 1.06, p < 0.0001). However, when patients were stratified into five risk groups using regression tree analysis (area under the curve: 85%), early SRT administration provided better metastasis-free survival in three groups only: (1) low risk: undetectable PSA after RP, Gleason score ≤7, and tumour stage ≥pT3b, (2) intermediate risk: undetectable PSA after RP with Gleason score ≥8, (3) high risk: PSA persistence after RP with Gleason score ≤7.

Conclusions

We developed an accurate risk stratification tool to facilitate the individualised recommendation for early SRT based on prostate cancer characteristics. Early SRT proved to be beneficial only in selected groups of patients who are more likely to be affected by clinically significant but not yet systemic recurrence at the time of salvage treatment administration.

Patient summary

In patients affected by prostate cancer recurrence after radical prostatectomy, the early administration of salvage radiation therapy is beneficial only for selected subgroups of patients. In this study, these groups of patients were identified.  相似文献   
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