Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Filtering Surgery”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,297 records · Page 72Linked to original sources

[Tissue micro-diastasis and closed micro-cavities of the surgical zone in glaucoma surgery].

Investigation of methods of antiglaucoma surgery in order to control the cicatrization of filtration routes of intraocular fluid discharge is carried out at the Vladivostok Medical Institute since 1989. A total of 662 operations are analyzed, which were carried out using an original method with "inverted trapezium"-shaped dissection of the deep tissues of the sclera. A microsurgical knife designed by the authors and patented was used. The results of operations indicate their sufficiently high hypotensive effect and a low incidence of complications. The authors claim that several filtering components are advisable in antiglaucoma surgery. Simplification of the technique of antiglaucoma operation, based on the concept of micro-diastasis and micro-cavities, deserves to be further researched.

Female↗

The effect of cataract extraction with implant in glaucomatous eyes.

The effect of cataract surgery in patients with glaucoma controlled by either topical medication or surgery was assessed in 64 patients. At one year there was a small significant fall in intraocular pressure (IOP) for eyes without previous surgery (preoperative IOP 18.9 +/- 4.7, range 12 to 35 mmHg; postoperative IOP 16.3 +/- 3.4, range 10 to 26 mmHg; P < 0.01) and also for those with previous surgery (preoperative IOP 15.0 +/- 4.3, range 3 to 22 mmHg; postoperative IOP 14.2 +/- 3.7, range 6 to 22 mmHg, P < 0.05). There was a significantly greater incidence of high rise in IOP to 30 mmHg or more immediately after operation in patients without (32%) than those with previous surgery (13%) (chi 2 = 3.9; P < 0.05). Complications were minimal in each group. Iridotomy to deliver the nucleus was necessary in nine eyes without and 21 with previous surgery. Cataract extraction usually causes only a small fall in IOP in glaucomatous patients. If a separate corneal section is used there is no loss of function of the filtering bleb in patients with previous glaucoma surgery.

Aged↗

Reliability of assessing interproximal bone loss by digital radiography: intrabony defects.

AIM: The aim of the present study was to assess the reproducibility and validity of linear measurements of interproximal bone loss in intrabony defects on digitized radiographic images after application of different filters and magnifications. METHODS: Immediately before surgery 50 radiographs of 50 periodontally diseased teeth exhibiting interproximal intrabony defects were obtained by a standardized technique in 50 patients. Intrasurgically the distances from the cementoenamel-junction (CEJ) to the alveolar crest (AC) and from the CEJ to the deepest extension of the bony defect (BD) were assessed. All radiographs were digitized by a flatbed scanner (resolution: 600x1200 dpi). Using the FRIACOM-soft ware, the linear distances CEJ to AC and CEJ to BD were measured at 50 intrabony defects on digitized but unchanged radiographic images and also after use of 2 different basic image processing modes (filters: enhancement of grey level differences, spreading of grey values) with 7-fold and 14-fold magnification by 2 different examiners. RESULTS: Repeated measures MANOVA revealed reproducibility of the measurement of the distance CEJ to AC to be significantly influenced by examiner (p=0.027) and filter in combination with the height of 2 wall component of the intrabony defect (p=0.066). For the distance CEJ to BD filters had significant influence on reproducibility in correlation with vertical angulation difference (p=0.001). On the average in this study radiographic measurements tended to overestimate the amount of bone loss as assessed by intrasurgical measurements (CEJ-AC: 0.74-1.91 mm; CEJ-DB: -0.04-0.77 mm). Validity of measurement of the distance CEJ-AC was shown to be significantly influenced by the depth of the intrabony defect (p<0.003). Validity of the distance CEJ-BD was significantly influenced by intrasurgically assessed bone loss (p=0.029), horizontal angulation (p=0.066). Filters influenced the validity only in combination with examiner (p<0.001). CONCLUSIONS: In this study, the chosen digital manipulations (filters: spreading, structure) of radiographic images failed to result in statistically significantly more reproducible or valid measurements of interproximal bone loss within intrabony defects when compared to the digitized but unchanged images. All radiographic assessments on the digitized images except for use of enhancement of grey level differences (structure) came close to the intrasurgical gold standard.

Adult↗

Albumin priming does not prolong hemofilter life.

The hypothesis was tested that prepriming a hemofilter and lines with heparinized human albumin (NSA) instead of heparinized saline (NS) increases filter survival time. In a university affiliated intensive care unit, all patients were eligible who required continuous venovenous hemodiafiltration and who did not have pre-existing coagulopathy or contraindications to heparin. New hemofilters were randomized to priming with 2 liters NS or 1 liter NS followed by 500ml NSA. The prime was recirculated for at least 30 minutes before connection to the patient. Anticoagulation was tightly controlled, aiming for a patient activated partial thromboplastin time (APTT) of 60 seconds. Survival analysis was used to compare filter life. Elective discontinuation (e.g., for surgery) were treated as censored data. A total of 91 hemofilters were used in 40 patients during 9 months: 45 randomized to NS, and 46 to NSA. Of these, 57 hemofilters were used until spontaneous failure, 28 NS and 29 NSA; 34 hemofilters were electively discontinued, 17 in each group. Anticoagulation was identical in both groups; the mean APTT value (+/- SE) was 58.2 seconds (+/- 3.1) for NS and 58.0 seconds (+/- 2.8) for NSA (p > 0.9 unpaired t-test). Platelet counts were very similar at 170 x 10(9) (+/- 21.8) for NS and 181 x 10(9) (+/- 23.7) for NSA (p = 0.74 unpaired t-test). There was no significant difference in the filter life between the two groups. For NS, median filter life was 37.8 hours (range 0.6-120); for NSA, median filter life was 45.4 hours (range 2.5-109; p = 0.998 log rank). The power to detect a 50% improvement in filter life was > 90%. Based on this data, the use of albumin priming as an aid to increased hemofilter life can not be recommended.

Acute Kidney Injury↗

Blood-retinal barrier and autofluorescence of the posterior polar retina in long-standing pseudophakia.

PURPOSE: To study the physiological state of the retina in long-standing pseudophakic eyes using blood-retinal barrier (BRB) disruption and autofluorescence as parameters. SETTING: Miyake Eye Hospital, Nagoya, Japan. METHOD: This retrospective, case-controlled study sought to determine whether ultraviolet (UV)-light-filtering and blue-light-filtering intraocular lenses (IOLs) had different outcomes in severity of BRB disruption and autofluorescence of the posterior polar retina than clear (untreated) IOLs. RESULTS: Mean sodium fluorescein transmittance in eyes with untreated IOLs was 3.7 ng/mL +/- 2.2 (SD) 3 years after surgery (n = 40) and 3.5 +/- 1.8 ng/mL 8 years after surgery (n = 18). In eyes with a UV-filtering IOL, the values were 2.4 +/- 1.5 ng/mL (n = 39) and 2.6 +/- 2.0 ng/mL (n = 14), respectively. Eyes with a UV-filtering IOL had significantly lower transmittance (P < .01-< .05). Mean transmittance 5 years after surgery was 4.2 +/- 1.9 ng/mL in eyes with an untreated IOL (n = 31), 3.2 +/- 2.1 ng/mL in eyes with a UV-filtering IOL (n = 30), 2.8 +/- 1.9 ng/mL in eyes with a Menicon blue-light-filtering IOL (n = 20), and 2.6 +/- 1.8 ng/mL in eyes with a Hoya blue-light-filtering IOL (n = 21). The eyes with a UV-filtering and the blue-light-filtering IOLs had significantly lower transmittance than those with an untreated IOL (P < .01-< .05); the eyes with a Hoya IOL had a statistically lower mean than those with the UV-filtering IOL (P < .05). Mean autofluorescence was 44.9 +/- 6.8 (n = 14), 49.5 +/- 6.1 (n = 6), 53.0 +/- 11.9 (n = 15), and 64.5 +/- 13.2 (n = 7) at 1, 4, 9, and 14 years after surgery, respectively; there was a significant difference between 1 and 9 years and between 1 and 14 years (P < .05). CONCLUSION: Eyes with a UV-filtering or blue-light-filtering IOL had a lower incidence of BRB disruption than eyes with an untreated IOL. Autofluorescence increased with age, even in eyes with UV-filtering IOLs.

Aged↗

Robot-assisted surgery: the future is here.

According to L. Wiley Nifong, director of robotic surgery at East Carolina University's Brody School of Medicine, "Nationally, only one-fourth of the 15 million surgeries performed each year are done with small incisions or what doctors call 'minimally invasive surgery'." Robots could raise that number substantially (Stark 2002). Currently, healthcare organizations use robot technology for thoracic, abdominal, pelvic, and neurological surgical procedures. Minimally invasive surgery reduces the amount of inpatient hospital days, and the computer in the system filters any hand tremors a physician may have during the surgery. The use of robot-assisted surgery improves quality of care because the patient experiences less pain after the surgery. Robot-assisted surgery demonstrates definite advantages for the patient, physician, and hospital; however, healthcare organizations in the United States have yet to acquire the technology because of implementation costs and the lack of FDA (Food and Drug Administration) approval for using the technology for certain types of heart procedures. This article focuses on robot-assisted surgery advantages to patients, physicians, and hospitals as well as on the disadvantages to physicians. In addition, the article addresses implementation costs, which creates financial hurdles for most healthcare organizations; offers recommendations for administrators to embrace this technology for strategic positioning; and enumerates possible roles for robots in medicine.

Device Approval↗

Intra-aortic filtration: capturing particulate emboli during aortic cross-clamping.

Particulate emboli are an important factor in the development of complications after cardiac surgery. The use of an intra-aortic filter during aortic declamping has proved safe and effective in reducing the incidence of embolic complications. Because aortic cross-clamping is also associated with the risk of embolism, we measured the release of particulate emboli at the time of aortic cross-clamping and at declamping. We deployed intra-aortic filters (Edwards EMBOL-X Slim Protection System) at 2 different times during 15 consecutive cardiac procedures with cardiopulmonary bypass. Filter A was inserted before aortic cross-clamping and left in place for a mean time of 3 minutes, and Filter B was inserted before aortic declamping for a mean of 17 minutes. An independent institution performed histopathologic examination. All filters captured particulate emboli, independent of the patients' degree of proximal aortic atherosclerotic disease. Macroscopy showed that Filter A captured more particles (mean, 70 +/- 2.6) in 7 of 15 patients (46.7%), Filter B captured more particles (mean, 6.7 +/- 2.6) in 5 of 15 patients (33.3%), and the filters captured the same number in 3 of 15 patients (20%). Microscopy showed that both filters captured fibrous atheroma or fibrous cap in 10 of 15 patients. We observed no complications related to the use of the filters. Aortic cross-clamping is associated with a high risk of embolism. We suggest that optimal protection against embolism during cardiac surgery can be achieved by applying intra-aortic filtration not only before aortic declamping but also before aortic cross-clamping.

Aged↗

Atrial fibrillation after coronary artery bypass surgery: P wave signal averaged ECG, clinical and angiographic variables in risk assessment.

BACKGROUND: Atrial fibrillation (AF) is a commonly encountered arrhythmia and occurs in up to 40% of patients after coronary artery bypass surgery (CABG). The preoperative signal averaged ECG (SAECG) P wave may be useful indicator of AF after CABG. We prospectively analyzed the predictive value of SAECG P wave compared to clinical variables. METHODS: Fifty-three patients with coronary artery disease undergoing first elective CABG were enrolled. All patients had P wave specific SAECG, standard 12 lead ECG, ejection fraction and left atrial posteroanterior diameter from the echocardiogram within the 24 h before surgery. From the SAECG P wave, filtered P wave duration was measured. Lead II P wave duration, left atrial enlargement and left ventricular hypertrophy were determined from standard ECG. Patients were continuously monitored during their postoperative period and serial ECGs were taken. RESULTS: During an observation period of up to 16 days, 19 (35.8%) patients developed AF 2.8+/-1.3 days after CABG. Patients with AF more often had left atrial enlargement (LAE) on ECG (P = 0.041) and right coronary artery (RCA) lesion (P = 0.0034). The filtered P wave duration on the SAECG was significantly longer in the AF patients than those without AF (129.7+/-13.2 ms versus 113.9+/-9.0 ms, P = 0.001). Logistic regression analysis identified independent predictors, estimated adjusted relative risk (95% confidence interval) of AF: with LAE, the relative risk was 2.72 (1.13-5.82), RCA lesion, the relative risk was 3.06 (1.45-6.45) and SAECG P wave duration >122.3 ms, the relative risk was 4.58 (2.11-9.97). The occurrence of AF was predicted by electrocardiographically determined left atrial enlargement with a sensitivity of 36%, specificity of 88%, positive predictive accuracy of 63%, negative predictive accuracy of 71%. If presence of right coronary artery lesion was evaluated these values were 63%, 79%, 63%, 79% subsequently. P wave duration >122.3 ms had a sensitivity of 68%, specificity of 88%, positive predictive accuracy of 76%, negative predictive accuracy of 83%. If both P wave >122.3 ms and presence of right coronary artery lesion were combined, these values were 47%, 94%, 81%, 76% subsequently. CONCLUSION: The predictors of AF after CABG were left atrial enlargement on standard 12 lead ECG, RCA lesion and SAECG P wave duration. Among these predictors, SAECG P wave duration was the best predictor of AF after CABG.

Aged↗

Deep venous thrombosis revealed during ultrasound-guided femoral nerve block.

Ultrasound imaging used to facilitate performance of a femoral nerve block also affords imaging of adjacent anatomical structures. Following a fracture of the femur, an ultrasound guided femoral nerve block (UGFNB) was performed to provide analgesia; this led to the incidental finding of a previously undiagnosed femoral vein thrombosis (DVT), resulting in a change in patient management before surgery. An inferior vena cava (IVC) filter was placed before intramedullary nailing of the fracture.

Adult↗

In vivo confocal microscopy of failing and functioning filtering blebs: Results and clinical correlations.

PURPOSE: To correlate clinical filtering bleb function with characteristics as detected by in vivo confocal microscopy. METHODS: In a case-matched cross-sectional study, 52 eyes of 48 patients were examined 1 day to 12.8 years after primary trabeculectomy (mean 375 d). The patients were examined clinically and by in vivo confocal microscopy (Rostock Cornea Module/Heidelberg Retina Tomograph II, Heidelberg Engineering, Inc, Heidelberg, Germany). Nine early and 17 late functioning blebs were pair-matched with malfunctioning blebs. Stromal fiber patterns, the number of intraepithelial and stromal cystic spaces, and the amount of cellular infiltrates were evaluated. RESULTS: Four stromal patterns (trabecular, reticular, corrugated, compacted) invisible to slit-lamp biomicroscopy could be distinguished by in vivo confocal microscopy. The trabecular pattern occurred only in functioning blebs, particularly early postoperatively. Intraepithelial cystic spaces were associated with functioning late blebs, whereas they were equally distributed in early blebs. In contrast, stromal cystic spaces indicate function in early blebs, whereas in late blebs the number of these cavities was similar in both groups. The density of intraepithelial and stromal round cells was higher in functioning late blebs compared with malfunctioning late blebs. CONCLUSIONS: In vivo confocal microscopy allows to assess filtering bleb structures that are invisible biomicroscopically. Some morphologic features detected by this technique seem to indicate filtering bleb function and time after surgery. The predictive value of these features deserves further clarification in a prospective longitudinal study.

Aged↗

3-D snake for US in margin evaluation for malignant breast tumor excision using Mammotome.

The goal of this paper is to use the three-dimensional (3-D) snake technique in 3-D ultrasound to obtain the tumor contour for the pre- and the post-operative malignant breast excision by the vacuum assisted biopsy instrument Mammotome. This technique of assessing the margin of two can help the physician to evaluate the effect of the surgery. By using the anisotropic diffusion filter, the noise and speckles can be reduced. Then the stick detection is adopted for enhancing the edge. Finally, the gradient vector flow (GVF) snake is used to obtain the tumor contour. These techniques are extended to the 3-D techniques to increase the accuracy and robust of segmentation results. We hope that this study can help physicians to improve the minimal invasive operation for a breast tumor.

Anatomy, Cross-Sectional↗

Sentinel lymph node mapping for breast cancer: analysis in a diverse patient group.

PURPOSE: To evaluate sentinel lymph node mapping in patients with breast cancer. MATERIALS AND METHODS: Sixty-two patients with breast cancer scheduled to undergo axillary nodal dissection underwent scintigraphic localization of sentinel lymph nodes with filtered technetium 99m sulfur colloid. At surgery, isosulfan blue was injected. Sentinel nodes were identifiable by blue color and by radioactivity with hand-held gamma probe. Results were analyzed statistically. RESULTS: A sentinel lymph node was identified in 49 patients (79%). Lymph nodes were positive for metastatic disease in 26 patients (42%). The mapping success rate was 78% (n = 21) in the 27 patients with no prior surgery, 78% (n = 18) in the 23 patients with prior surgery, and 86% (n = 12) in the 14 patients with prior chemotherapy. Axillary nodes were positive in 11 (41%) of the 27 patients with no prior intervention, six (26%) of the 23 patients with prior surgery, and 10 (71%) of the 14 patients with prior chemotherapy. There were no false-negative findings in patients without prior intervention. Four patients with positive nodes had false-negative sentinel nodes. CONCLUSION: Sentinel lymph node mapping and biopsy without axillary dissection is appropriate in patients with breast cancer who have not undergone prior intervention. Further study is necessary to ascertain the accuracy of the procedure for patients who have undergone presurgical chemotherapy or previous excisional biopsy.

Adult↗

[Ilio femoral thrombosis: an infrequent complication of an aortic and iliac aneurysm. Report of two cases].

Death due to rupture of and abdominal aortic or iliac aneurysm, is their most frequent complication. We report two male patients, both over seventy years old, who presented with unexplained unilateral ilio-femoral deep vein thrombosis. During diagnostic work up an aortic and iliac aneurysm, compressing the deep venous system with secondary thrombosis, was found. In both patients a prophylactic inferior vena caval filter was inserted and standard elective surgery was then performed. No perioperative complications occurred and both patients remain asymptomatic during follow up. Deep vein thrombosis due to compression by an abdominal aortic and iliac aneurysm is infrequent. It must be ruled out together with intrabdominal cancer, in the elderly patient presenting with unexplained deep vein thrombosis.

Aged↗

[The eye department at Copenhagen municipal hospital: part 2: Holm's epoch, 1929-57].

Ejler Holm (1887-1966) was the chief at the eye department, the Municipal Hospital in Copenhagen in the period 1929-57. He got the longest period in the history of the department, 28 years. Holms qualification to get the appointment are described, especially in his medical thesis concerning the yellow pigment in the central part of the retina (bleaching opsin). Never the less he got an unjustified attack from the opponent professor Marius Tscherning (1854-1939) including the theory of duplicity (day function and night function of the human eye), and the German ophthalmic science. The struggle to become professor ophthalmologiae at the University of Copenhagen in 1925 is mentioned. The eye diseases and their therapy in the period are exemplified from original patient records from 1930 (tuberculosis, venerea, dry eye, morsum hirudin etc.), 1940 (chemotherapeutica, trachoma, glaucoma etc.) and 1949 (penicillin, injections of milk i.m., cauterisation, trachoma etc.), supplemented by Holms records from own practic in 1934, surgery protocols and statistical material from the period. The number of cataract extractions (extracapsular) increased considerable with more liberal indication and regime. Also the number of squint operations are increasing, where sutures are more often used. Glaucoma-surgery increased only slightly with more filtering operations (Elliots trepanation, Holth-iridencleise) instead of simple iridectomy. Eye pathological examinations become more qualified. Psychiatric, simulating and troublesome patients are described. There are very great difference between diagnosis and treatment at that time, compared with today.

Denmark↗

Blood-retinal barrier dysfunction at the pigment epithelium induced by blue light.

Exposure to low-intensity white light can induce dysfunction of the blood-retinal barrier (BRB) at the retinal pigment epithelium (RPE). To determine whether the shorter wavelengths white light are responsible for this dysfunction, rabbit retinas were exposed to blue light (400-520 nm) or yellow light (510-740 nm). The permeability of the BRB, a parameter for the integrity of the barrier, was quantified with vitreous fluorophotometry. Morphologically, the barrier at the RPE was visualized on light and electron microscopy using horseradish peroxidase (HRP) as a tracer. Seventeen pigmented rabbits were exposed to blue light and 11 were exposed to yellow light. Vitreous fluorescein leakage increased with the exposure energy according to a power function (correlation coefficient > 0.79). The threshold energy for an increase in BRB permeability was 50 J/cm2 (0.014 W/cm2 for 1 hr) after blue and 1600 J/cm2 after yellow light. HRP tracing demonstrated that after blue light exposure, a significant fluorescein leakage on fluorophotometry corresponded to the presence of HRP in the RPE cells and in the subretinal space. After yellow light exposures of < 3700 J/cm2 and in rabbits with no significant fluorescein leakage, the HRP was limited to the choroidal capillaries and Bruch's membrane. These results demonstrate that the blue component of white light causes dysfunction of the BRB at the RPE 30 times more effectively than the longer wavelength fraction of white light. As a result, a blue light blocking filter should be used in ocular surgery on humans when an operating microscope is being used (light power 0.1-0.9 W/cm2).

Animals↗

Effects of a heat and moisture exchanger on carbon dioxide equilibrium during mechanical ventilation with the Bain circuit.

The introduction of a heat and moisture exchanger (HME) into the anaesthetic circuit may cause a rise in carbon dioxide (CO2) tension through an increase in dead space. We studied the effects of the Ultipor Pall BB50 filter included 'in series' in the Bain circuit on CO2 equilibrium. Arterial carbon dioxide tension (PaCO2) was measured in 81 patients scheduled for elective surgery before and after the insertion of the filter. Results showed that: females were always more hyperventilated than males when fresh gas flow was set at 70 ml kg-1 ideal body weight; the inclusion of the filter increased the PaCO2 in the group as a whole (the difference was statistically, but not clinically, significant); PaCO2 increased after the application of the filter only in females; the effects of the filter were completely independent of the patient's age. It is concluded that the use of the Ultipor Pall BB50 filter is a safe procedure during mechanical ventilation with the Bain breathing system and there is no need to modify ventilation.

Adult↗