首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
The article deals with some methods of holography (holograms with inclined reference beam, in three-dimensional media after Yu. N. Denisiuk, holographic interferometry) as applied to studying anatomical objects. Approximate optical schemes and photographic copies of holograms of separate objects are presented. The comparative analysis of different methods enabled the authors to recommened for practical use the method of obtaining holograms in three-dimensional media for documentation of anatomical investigation and storage of information, holographic method of obtaining contour maps of the surface for quantitative characteristics of individual properties of the object and the method of double exposure for studying static and dynamic deformities.  相似文献   

2.
After reviewing the literature on the subject, the authors examine all the cases of aortic aneurysm referred to their attention. From the tests performed, they note that males are most often affected and the age group with the highest incidence is the seventh decade of life, in particular between 60-66 years old. After having observed a pulsing abdominal mass leading to a suspected diagnosis, the radiological methods recommended by the authors include echotomography or CT, or if required, magnetic resonance. Arteriography is less convincing than the previous tests for diagnostic purposes because, as well as providing a false image of the vessel lumen (owing to the overlay of stratified thrombi it can show a virtually normal lumen), it may cause a risk of embolism. The surgeon therefore prefers an intraoperative finding in the case of subrenal aneurysm. In conclusion, faced with a diagnosis of aneurysm of the abdominal aorta, in the majority of cases, having prepared the patient, it is necessary to perform aorto-bisiliac or bifemoral graft surgery depending on aneurysm size as soon as possible in order to avoid the fissuration or even the rupture of the aneurysm.  相似文献   

3.
This paper describes augmented reality visualization for the guidance of breast-conservative cancer surgery using ultrasonic images acquired in the operating room just before surgical resection. By combining an optical three-dimensional (3-D) position sensor, the position and orientation of each ultrasonic cross section are precisely measured to reconstruct geometrically accurate 3-D tumor models from the acquired ultrasonic images. Similarly, the 3-D position and orientation of a video camera are obtained to integrate video and ultrasonic images in a geometrically accurate manner. Superimposing the 3-D tumor models onto live video images of the patient's breast enables the surgeon to perceive the exact 3-D position of the tumor, including irregular cancer invasions which cannot be perceived by touch, as if it were visible through the breast skin. Using the resultant visualization, the surgeon can determine the region for surgical resection in a more objective and accurate manner, thereby minimizing the risk of a relapse and maximizing breast conservation. The system was shown to be effective in experiments using phantom and clinical data.  相似文献   

4.
PURPOSE: To evaluate the surgical experiences and patient preference with 3 local anesthesia techniques for small incision cataract surgery. SETTING: Department of Ophthalmology, Hj?rring Hospital, Denmark. METHODS: This prospective, randomized study included 66 patients having simultaneous bilateral cataract surgery. There were 3 test groups, each containing 2 of the following local anesthesia techniques: retro/peribulbar (RBA), sub-Tenon's (STA), or topical (TA). Each patient served as his or her own control. No medical sedation was used. Patient response to each anesthesia technique was evaluated by the surgeon based on surgical difficulties, a nurse using hand-holding tension and verbal interaction, and a visual analog pain score. Patients were also asked which of the 2 techniques they preferred and their reasons. RESULTS: No local anesthesia techniques interfered with surgery. The order of a positive pain/discomfort response during surgery was TA > STA > RBA. Significantly more pain occurred with application of RBA than with STA or TA. No postoperative pain was recorded with any method. Fifty-six percent of patients said they preferred 1 technique over the other; 16% of patients having STA would not do so again, 19% would not have TA again, and 40% would not have RBA again. The main reasons for preferring STA and TA were fear of or pain from a retrobulbar injection. The main reasons for preferring RBA were less awareness, anxiety, and surgical pain. Immediate visual recovery seemed to be of minor importance in patients' choice of an anesthesia technique. CONCLUSION: Although less discomfort/pain occurred during surgery with RBA, patients preferred STA and TA primarily because of the inconvenience or pain of the retrobulbar injection. Although medical sedation was not used in this study, the pain/discomfort ratio from surgery was not greater than in studies using intravenous sedation, indicating that the use of medical sedation should be re-evaluated.  相似文献   

5.
BACKGROUND: The qualities of visual perception and of motor reaction to the visual stimulus have never been studied in reference to the type of video-camera system (2-D vs 3-D) used during laparoscopy. METHODS: The study was designed in two parts. The first evaluated the ability of the eye to discriminate how objects are spaced relative to one another. The second investigated the motor reaction to the visual stimulus in an environment where depth was the preponderent cue. The tests were performed in a pelvi-trainer in which were inserted different modules built either for visual observation (Part 1) or for evaluation of motor ability (Part 2). Variables studied during Part 1 were the time required to do the test and the number of errors committed during its performance. The variable evaluated during Part 2 was the time needed to terminate the test. Each of these two parts of the study were completed alternating the 2-D and 3-D systems. A total of 304 observations were recorded. Statistics used were the paired t-test, the independent group t-test, and the Newman-Keuls multiple comparisons test. RESULTS: Results of Part 1 of the study confirm that visual perception varies significantly among individuals (n = 10) (p < 0.05) and that a true 3-D video-camera system facilitates visual perception when compared to a 2-D system (p < 0.001). Results of Part 2 of the study also show significant differences among participants (n = 9)(p < 0.05). The true 3-D system allowed significantly faster motor performances than the 2-D system (p < 0.001). CONCLUSION: Our experiment shows that the 3-D system allowed significant improvements in the execution of the evaluated parameters. Also noted were significant differences among participants in term of visual and motor skills.  相似文献   

6.
OBJECTIVE: This study aimed to assess patient satisfaction and change in functional status after surgery for epiretinal membrane (ERM), rhegmatogenous retinal detachment (RRD), and complex retinal detachment (CRD). This study also aimed to determine whether objective measures of vision are predictive of subjective improvement after surgery. DESIGN: The study design included patient interviews and retrospective chart review. PARTICIPANTS: Participants were those patients who underwent surgery for ERM, RRD, or CRD by one surgeon at the Bascom Palmer Eye Institute between January 1, 1993, and December 31, 1994. INTERVENTION: Patient satisfaction and patients' perceptions of the impact of surgery on their functional status were assessed by telephone interviews conducted by one interviewer at least 6 months after surgery. MAIN OUTCOME MEASURES: Responses to patient satisfaction survey and subjective change in patients' functional status were measured. RESULTS: Of 187 eligible patients, 146 (78.1%) could be contacted and all agreed to participate. Ninety patients (61.6%) reported improved functioning after surgery in 2 or more of the 5 activities investigated. Twenty-one patients (14.4%) reported worse postoperative vision than expected, but only 5 patients (3.4%) thought surgery had not been worthwhile. One hundred forty-three patients (97.9%) reported adequate explanation of surgery and its expected results. Patients with preoperative study eye visual acuity between 20/40 and 20/200 were most likely to improve in two or more activities. Lower preoperative worse eye vision and better final study eye vision were associated with a greater likelihood of satisfaction after surgery. Diagnostic category was not predictive of change in functional status or patient satisfaction. CONCLUSIONS: There is a high rate of patient satisfaction and improved functional status after surgery for ERM, RRD, and CRD, even among patients with good fellow eye vision.  相似文献   

7.
Notes that holographic reprocessing (HR) is a cognitive-experiential psychotherapy based on S. Epstein's theory of personality, cognitive experiential self-theory (CEST). CEST is an information processing theory that can provide an integrative framework for therapeutic reprocessing techniques. This article overviews HR and introduces the concept of "experiential holograms." An experiential hologram describes a theme of experiences that reemerges throughout a person's life in various contexts. In HR, the dynamics of experiential holograms and the characteristic responses to the holograms are accessed through associations in the experiential system. The holograms are then reprocessed by using cognitive and experiential techniques. Case examples are used to illustrate these concepts. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

8.
Modern cataract surgery is characterized by minimal invasive techniques that have been introduced during the past decade. These include phacoemulsification, capsulorhexis, foldable intraocular lenses and small tunnel incisions. High success rates coupled with low complication rates have resulted in a change in indications--cataract surgery is no longer performed merely to prevent blindness, but also to improve vision in patients whose professional or private visual demands are compromised by the onset of lens opacification. To ensure that their cooperation with the ophthalmic surgeon results in optimal benefit to the patient, it is important for general practitioners and internists to be conversant with the risk factors and contraindications for cataract surgery.  相似文献   

9.
The projection of 3-D objects to 2-D images necessitates a loss of information, thus the shape of volumetric objects depicted in images is inherently ambiguous. The results of 3 experiments suggest observers use mental models of the local visual environment to constrain image interpretation. These models change quickly and dramatically to accommodate implicitly acquired information. Observers viewed very high-contrast (2-tone) images of novel volumetric objects. Before priming, novel 2-tone images appeared 2-D. After incidental exposure to similar objects in grayscale or familiar objects in 2-tone, the test images appeared volumetric. Incidental learning appears to alter observers' mental models, thus causing an alteration in image interpretation in the absence of any image change. Highlights were interpreted more accurately than shadows, suggesting shadows play a secondary role in shape recovery. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

10.
Six patients with pulmonary emphysema scheduled to undergo thoracoscopic lung volume reduction surgery (TLVRS) were evaluated by three-dimensional (3-D) dynamic pulmonary xenon-133 SPECT. Serial 30-second dynamic SPECT data for equilibrium and washout (for 5 min) were acquired using a continuous repetitive rotating acquisition mode with a triple-detector SPECT system. SPECT data were reconstructed to 3-D images with a color, surface-rendering technique, and a 3-D fusion image of the 3-min washout image over the equilibrium image was obtained. Regional ventilation was visually assessed on the fusion 3-D images and quantified by xenon-133 half-washout time (T1/2) and mean transit time (MTT). The 3-D fusion image localized and lateralized the worst diseased sites with xenon-133 retention. Xenon-133 retention, T1/2 and MTT were reduced on these images in five patients with improved pulmonary function tests following TLVRS. However, xenon-133 retention was greater in one with asynchronous diaphragm movement after TLVRS. This modality will assist TLVRS in determining the lung resection target and in evaluating the treatment effect.  相似文献   

11.
JB Jonas  WM Budde  S Panda-Jonas 《Canadian Metallurgical Quarterly》1998,105(7):1234-7; discussion 1237-8
OBJECTIVE: The purpose of the study was to evaluate transpupillary removal of silicone oil combined with cataract surgery in patients after pars plana vitrectomy. DESIGN: A prospective case-control study. PARTICIPANTS: Fifty consecutive patients underwent cataract surgery combined with removal of silicone oil, which had served as intraocular tamponade after pars plana vitrectomy. In 28 patients, silicone oil was removed through a planned posterior capsulotomy, and in 22 patients, silicone oil was removed through pars plana sclerotomies. All patients were operated on by the same surgeon. INTERVENTIONS: Pars plana vitrectomy, cataract surgery, and silicone oil removal were performed. MAIN OUTCOME MEASURES: Frequencies of retinal redetachment, secondary cataract, cystoid macular edema, and vitreous hemorrhage; visual acuity; intraocular pressure; and duration of surgery and visual rehabilitation were measured. RESULTS: Frequencies of postoperative vitreous hemorrhage (1 of 28 [4%] vs. 10 of 22 [45%]) and secondary cataract (0 of 28 vs. 6 of 22 [27%]) were significantly lower (P < 0.05; chi-square test), and duration of surgery and visual rehabilitation were significantly shorter (P < 0.01) for patients with transpupillary silicone oil removal than for patients with drainage of silicone oil through pars plana sclerotomies. Rate of retinal redetachment (4 of 28 [14%] vs. 4 of 22 [18%]), time of retinal redetachment (36 +/- 32 postoperative days vs. 54 +/- 65 days), frequency of dislocated intraocular lenses (1 of 28 vs. 0 of 22), and postoperative visual acuity did not vary significantly between the two groups. Persisting comeal endothelial decompensation and clinically significant cystoid macular edema due to cataract surgery were not observed in any patient. CONCLUSIONS: Silicone oil removal can be combined with cataract surgery. In view of a decreased frequency of postoperative vitreous hemorrhage, reduced rate of secondary cataract, and shorter duration of surgery and visual rehabilitation, transpupillary drainage of silicone oil through a planned posterior capsulotomy compares favorably with removal of silicone oil through pars plana sclerotomies. Retinal redetachment usually occurs within the first 3 postoperative months.  相似文献   

12.
Clinical experiences of 35 cardiothoracic operations in Jehovah's Witness patients were presented with special reference to a method of taking informed consent for surgery. At first the surgeon explained the details of the proposed surgery including its risks and benefits. He should also express his confidence in accomplishing the operation without blood transfusion. Otherwise he should not dare to perform the operation. The surgeon asked the patient to talk about his or her religious belief in transfusion denial. Then the surgeon was allowed to talk about his professional duty and ethical belief in saving the patient at all costs. Finally, both the patient and the surgeon would sign the document of informed consent without fully determining whether or not the patient would undergo transfusion at an unexpected situation since the possibility of such unexpected necessity of blood transfusion was believed extremely low by both the surgeon and the patient. The trust of the patient in the technique of the surgeon was the key to this agreement.  相似文献   

13.
A recent theoretical investigation has demonstrated that three-dimensional (3-D) eye position dependencies in the geometry of retinal stimulation must be accounted for neurally (i.e., in a visuomotor reference frame transformation) if saccades are to be both accurate and obey Listing's law from all initial eye positions. Our goal was to determine whether the human saccade generator correctly implements this eye-to-head reference frame transformation (RFT), or if it approximates this function with a visuomotor look-up table (LT). Six head-fixed subjects participated in three experiments in complete darkness. We recorded 60 degrees horizontal saccades between five parallel pairs of lights, over a vertical range of +/-40 degrees (experiment 1), and 30 degrees radial saccades from a central target, with the head upright or tilted 45 degrees clockwise/counterclockwise to induce torsional ocular counterroll, under both binocular and monocular viewing conditions (experiments 2 and 3). 3-D eye orientation and oculocentric target direction (i.e., retinal error) were computed from search coil signals in the right eye. Experiment 1: as predicted, retinal error was a nontrivial function of both target displacement in space and 3-D eye orientation (e.g., horizontally displaced targets could induce horizontal or oblique retinal errors, depending on eye position). These data were input to a 3-D visuomotor LT model, which implemented Listing's law, but predicted position-dependent errors in final gaze direction of up to 19.8 degrees. Actual saccades obeyed Listing's law but did not show the predicted pattern of inaccuracies in final gaze direction, i.e., the slope of actual error, as a function of predicted error, was only -0. 01 +/- 0.14 (compared with 0 for RFT model and 1.0 for LT model), suggesting near-perfect compensation for eye position. Experiments 2 and 3: actual directional errors from initial torsional eye positions were only a fraction of those predicted by the LT model (e. g., 32% for clockwise and 33% for counterclockwise counterroll during binocular viewing). Furthermore, any residual errors were immediately reduced when visual feedback was provided during saccades. Thus, other than sporadic miscalibrations for torsion, saccades were accurate from all 3-D eye positions. We conclude that 1) the hypothesis of a visuomotor look-up table for saccades fails to account even for saccades made directly toward visual targets, but rather, 2) the oculomotor system takes 3-D eye orientation into account in a visuomotor reference frame transformation. This transformation is probably implemented physiologically between retinotopically organized saccade centers (in cortex and superior colliculus) and the brain stem burst generator.  相似文献   

14.
Results of treatment of 52 patients with amenorrhoea associated with hyperprolactinaemia are presented. All patients had a detailed radiological examination of the pituitary fossa, including lateral tomography in every patient and air encephalography in those in whom a pituitary tumour was suspected. There were 17 patients with untreated pituitary tumours, 5 patients with previously treated pituitary tumours and persisting hyperprolactinaemia, and 30 patients with normal pituitary radiology. Patients with pituitary tumours were treated either by transsphenoidal or transfrontal surgical extirpation of the tumour, followed, if necessary, by external irradiation and/or bromocriptine, Four patients were treated with external irradiation as primary therapy, and three patients who did not wish to conceive were treated with bromocriptine as primary therapy. Patients with normal radiological appearances were treated with bromocriptine as primary treatment. Ovulatory menstrual cycles developed in 42 patients and there were 19 pregnancies. Those ovulating but not conceiving had adequate nonendocrine factors to account for the disparity. Failure of response was seen in 10 patients and was due to inadequate fall of prolactin in response to surgery (2 patients), external irradiation (3 patients) and bromocriptine (1 patient), and gonadotrophin deficiency which developed after surgery in 3 patients but was present pre-operatively in 1. The relative merits of treatment by surgery, external irradiation and bromocriptine are discussed and a policy of treatment outlined.  相似文献   

15.
The purpose of this study was to evaluate the role of nasogastric (NG) decompression after laparotomy in pediatric surgical practice: 94 children who underwent abdominal surgery by a single surgeon were consecutively prospectively managed without postoperative NG tubes. Patients with either bowel obstruction or intra-abdominal infection were excluded from the study. These children were compared with 94 retrospective, matched controls who were routinely managed with postoperative NG decompression by the same surgeon. Data were analyzed with regard to patient, operative, and outcome variables. There was no difference in gender, age (3.8 +/- 0.5 vs 3.5 +/- 0.4 years, P > 0.7), or postoperative complications (P > 0.8) between the two groups. However, there was a higher incidence of postoperative vomiting (22% vs 11%, P > 0.05) in the children who did not have postoperative NG decompression. Nevertheless, a significant decrease in time to first feed, first stool, and discharge was noted in the group of patients managed without NG tubes (P < 0.05). NG decompression thus need not be routinely used in the pediatric patient undergoing abdominal surgery, as there is no difference in postoperative complications and the hospital stay is shortened.  相似文献   

16.
Massive stenosis of the larynx may present a potentially life-threatening situation for the patient, requiring immediate measures to ensure a patient's airway. The aim of this prospective study was to evaluate potential benefits of Superimposed High Frequency Jet Ventilation (SHFJV) in patients requiring microlaryngeal surgery due to massive stenosis of the larynx. Patients and methods: 23 patients (age range 1.5 to 90 years) with laryngeal stenosis grade 2 and 3 according to the Cotton scale were ventilated using SHFJV. The duration of the SHFJV was 12 to 116 minutes. SHFJV was performed using a Bronchotron Respirator via a jet-laryngoscope. Results: Arterial blood gases demonstrated paO2 between 71 and 295 mmHg and paCO2 of 28 to 81 mmHg. The mean FiO2 applied was 61.75 +/- 19.26. The airway pressure was measured at the tip of the jet-laryngoscope and was between 6 and 15 mmHg, and PEEP was 1 to 5 mmHg. In 13 patients a CO2 laser was utilised during surgery. Discussion: In all patients SHFJV was performed without problems. Since the ventilation is delivered above any possible stenosis the danger of barotrauma is minimised. The surgeon obtains optimal visibility of the larynx and is not obstructed in the surgical procedure. SHFJV enables both the surgeon and the anesthetist to perform their respective duties and therefore increases the safety of the patient in the management of such a difficult problem as massive stenosis of the larynx.  相似文献   

17.
OBJECTIVE: A retrospective study was undertaken to evaluate long-term anatomic and visual outcomes in eyes of children who underwent bilateral intraocular lens implantation. DESIGN: The study design was a review of medical records of 24 children operated on for bilateral cataracts and posterior chamber-intraocular lenses. PARTICIPANTS: Twenty-four children operated on for bilateral cataracts by 1 surgeon between February 1980 and February 1995 were studied. INTERVENTION: Cataract extraction with bilateral posterior chamber-intraocular lens implantation was performed. MAIN OUTCOME MEASURES: Best-corrected visual acuity, visual acuity without correction, intraocular pressure, manifest refraction, and any intraoperative or postoperative complications were measured. RESULTS: At last follow-up (mean follow-up, 50.8 months; range, 10-149 months), the intraocular lens was in good position and the intraocular pressure was normal without medication in all eyes. Four years after surgery, 79.2% (19 of 24) of first eyes achieved a best-corrected visual acuity of 20/40 or better compared to 66.7% (16 of 24) of second eyes. No eye had any loss in best-corrected visual acuity. In first eyes of 3- to 8-year olds at the time of surgery, 73.3% (11 of 15) achieved a spherical equivalent within 2 diopters of the intended at 4 years after surgery compared to 80% of second eyes. In the 9- to 18-year-old group, 88.9% (8 of 9) of first eyes and 100% of second eyes achieved a spherical equivalent within 2 diopters of the intended at 4 years after surgery. Intraoperative and postoperative complications were minimal. CONCLUSIONS: Long-term anatomic and visual results have been gratifying in this series of patients with bilateral implants.  相似文献   

18.
Helical computed tomography was performed with intravenous contrast material administration in ten patients with hepatic tumors (metastatic tumor, n = 6; hepatocellular carcinoma, n = 4). Maximum intensity projection (MIP) images of intrahepatic portal venous branches and hepatic veins, and shaded surface display (SSD) images of the hepatic tumors were reconstructed for each patient. The MIP image and SSD image were fitted to overlap on a single display to obtain three-dimensional (3-D) images showing both the hepatic vessels and hepatic tumors. Subsegmental localization of the tumors determined from the 3-D images proved to be correct in all of the six patients who received hepatic resection after examination. 3-D images seem to be useful for preoperative assessment of hepatic tumors.  相似文献   

19.
PURPOSE: We studied the degree of agreement between hypospadias patient and surgeon satisfaction with the cosmetic surgical result, and the relation between penile length, meatal position and patient satisfaction. MATERIALS AND METHODS: Cosmetic and functional results in 35 boys with hypospadias were assessed, and a standardized questionnaire was completed by patients and surgeon. RESULTS: There was hardly any agreement between patient and surgeon satisfaction with patient penile appearance. Patients were less satisfied than the surgeon. No significant correlation was noted between penile satisfaction and penile length. Patients with a retracted meatus were less satisfied with the meatal position than those with a glanular meatus. Of the 35 patients 4 underwent repeat surgery after our study. CONCLUSIONS: Hypospadias surgeons should explicitly asked if patients are satisfied and they should follow patients through adolescence.  相似文献   

20.
The objective of this study was to evaluate the efficacy of the local use of oxytocin as adjuvant treatment in conservative surgery for tubal pregnancy. The patients were 25 women with laparoscopic diagnosis of tubal pregnancy who were candidates for salpingotomy. Before salpingotomy, each patient was randomly allocated to intramesosalpingeal injection of 20 IU oxytocin diluted to 20 ml with saline solution or 20 ml saline solution. The surgeon then proceeded with salpingotomy and removal of the pregnancy according to the usual technique. The main outcome measures were bleeding during salpingotomy, ease of removal of the pregnancy, bleeding at the site of the pregnancy, and need for recourse to salpingectomy. Twelve women were randomized to the oxytocin group and 13 to the control group. Examination of the surgeons' assessments of the difficulties encountered at the different stages of surgery revealed statistically significant differences between the oxytocin group and controls in each variable. In particular, the amount of endosalpingeal bleeding after removal of the pregnancy was less in the oxytocin group. In one control patient, persistent bleeding due to incomplete trophoblast removal forced the surgeon to perform salpingectomy. Our results indicate that intramesosalpingeal injection of oxytocin facilitates the performance of conservative laparoscopic treatment for tubal pregnancy.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号