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No-stitch, small incision cataract surgery with flexible intraocular lens implantation.

Small incision cataract surgery has several advantages over conventional surgery, including faster postoperative visual rehabilitation. We evaluated 100 consecutive cases of no-stitch, small incision surgery with a square sclerocorneal tunnel and a flexible intraocular lens. Permanent self-sealing of the wound seemed to increase intraoperative safety considerably. With the specific incision used, corneal trauma and irrigation fluid outflow were minimal. Refraction and K-readings stabilized within the first postoperative week, which is when most eyes attained best final visual acuity. No early peak or protracted drift of astigmatism occurred. Minimally leaking wounds in three eyes were left unsutured; a transient filtering bleb was observed in two of these eyes after resorption of an intracameral air bubble. Our results support the theoretical concept and justify the use of no-stitch, small incision surgery.

Cataract Extraction↗

Embol-X intra-aortic filtration system: capturing particulate emboli in the cardiac surgery patient.

We sought to evaluate the effectiveness of using an intra-aortic filtration system for the prevention of particulate emboli transport and the minimization of significant postoperative complications associated with particulate emboli. Between October of 2000 and October 2001, a total of 146 patients were enrolled at Advocate Christ Medical Center as part of the multi-institutional randomized trial (1289 patients at 22 centers). A total of 74 patients (51%) received the Embol-X intra-aortic filter and 72 patients (49%) were enrolled in the control group. Patients were evaluated for neurological deficit, myocardial infarction, renal insufficiency/failure, limb ischemia, and death at 12-hour, 24-hour, 72-hour, 7-day, and 30-day postoperative intervals. All filters received histological examination for particulate matter. Particulate matter was isolated in 70 (94.5%) of the filters successfully deployed. There was no statistically significant difference in the device related events between the filter and conventional cannulation groups (9/74 = 12.1% vs. 7/72 = 9.7%). Although not clinically evident, the primary event for both groups was ascending aortic intimal tears. There was one death in each of the groups not related to the filter or cannula used. The use of the Embol-X intra-aortic filter system has proven to be a safe and effective means to reduce the introduction of particulate emboli into the systemic circulation. Clearly, the reduction of particulate matter by as much as 95% justifies its use in cardiac surgery patients identified with an increased pre-operative embolic risk.

Aorta↗

Managing the evidence flood.

The problem of lack of transfer of knowledge in surgery is well illustrated by the variations in surgical practice across areas and countries. Surgery is not unique in this respect, and such variations have been documented in virtually all specialties and in primary care. The first issue is recognition that there is an inescapable and growing information problem. Unless we focus some of our research and practice effort on better organizing, filtering, and using the research that we have, the gap between what we know and what we do will continue to grow.

Evidence-Based Medicine↗

Optical coherence tomographic findings of the anterior segment after nonpenetrating deep sclerectomy.

PURPOSE: To evaluate the efficacy of optical coherence tomography for the analysis of anterior segment after glaucoma surgery. DESIGN: Interventional case report. METHODS: In a 79-year-old man with primary open-angle glaucoma, optical coherence tomography was performed on the left eye after nonpenetrating deep sclerectomy. RESULTS: Optical coherence tomography showed thinning of the conjunctiva over the filtering bleb, presence of a space under the scleral flap that is considered as a lake, and presence of fibrous tissue in the bleb. CONCLUSION: This case indicates that optical coherence tomography, a noninvasive, noncontact optical imaging modality, may be useful for analysis of the anterior segment after glaucoma surgery.

Aged↗

Histopathological features of vitreous removed at macular hole surgery.

OBJECTIVE: To describe the histopathological features of the vitreous removed at surgery for macular holes in 200 consecutive cases. METHODS: The complete vitrectomy specimen in each case was concentrated by means of cellulose membrane filters and stained for light microscopy. The cases were organized into 5 categories: (1) all cases (N = 200), (2) eyes without previous vitrectomy (n = 174), (3) eyes with previous vitrectomy (n = 26), (4) idiopathic cases (n = 143), and (5) traumatic (accidental or surgical) cases (n = 31). The type and frequency of tissue fragments present in the vitreous were determined for each case. RESULTS: Fibrocellular and cellular membrane fragments were found in a minority of cases in all categories. Retinal fragments were a rare finding, present in only 4 cases. Inflammation was present in 57 (28.5%) of all cases. CONCLUSIONS: The absence of fibrocellular and cellular membrane fragments in the majority of cases suggests that mechanisms other than cellular proliferation are important in the pathogenesis of macular holes. These fragments are, however, the likely histopathological correlate of the opercula that are often observed clinically in patients with macular hole. Opercula rarely if ever contain retinal fragments, and thus are better termed pseudo-opercula, as has been previously suggested. The cellular proliferation and inflammation that are observed in some of the cases are likely a secondary or reactive process.

Aged↗

Meta-analysis of randomized controlled trials investigating the risk of postoperative infection in association with white blood cell-containing allogeneic blood transfusion: the effects of the type of transfused red blood cell product and surgical setting.

Previous meta-analyses of the randomized controlled trials (RCTs) investigating the association of perioperative allogeneic blood transfusion (ABT) with postoperative bacterial infection included studies transfusing either autologous or white blood cell (WBC)-reduced allogeneic red blood cells (RBCs) or whole blood to the control arm, and they were unable to investigate the type of RBC product administered as an explanation for the disagreements among the studies. The availability of additional RCTs has permitted investigation of this hypothesis in a meta-analysis restricted to RCTs transfusing WBC-reduced allogeneic RBCs or whole blood to the control arm. In this analysis, across 5 RCTs comparing recipients of non-WBC-reduced versus WBC-reduced allogeneic RBCs, there was no difference (P > .25) in the risk of postoperative infection between recipients of buffy-coat-reduced versus WBC-reduced allogeneic RBCs filtered before storage (summary odds ratio [OR] = 1.19; 95% confidence interval [CI], 0.87-1.63). In contrast, across 3 RCTs, there was an increased (P < .05) risk of postoperative infection in recipients of non-buffy-coat-reduced allogeneic RBCs, or whole blood, as compared with recipients of WBC-reduced allogeneic RBCs, or whole blood, filtered before or after storage (summary OR = 1.77; 95% CI, 1.02-3.09). Moreover, across 3 RCTs that enrolled patients undergoing open-heart surgery, there was an increased (P < .05) risk of postoperative infection in recipients of buffy-coat-reduced (compared with WBC-reduced) allogeneic RBCs (summary OR = 1.39; 95% CI, 1.08-1.80), but the findings of 5 RCTs that enrolled patients having abdominal surgery could not be combined because of extreme variation in the results of the studies. RCTs conducted in the setting of open-heart surgery or transfusing non-buffy-coat-reduced RBCs or whole blood to the treatment arm had administered various RBC products to the control arm, however, and thus the medical heterogeneity of the studies precludes any conclusion about an immunomodulatory (TRIM) effect of ABT mediated by non-buffy-coat-reduced RBC products. To determine whether such a deleterious immunomodulatory effect of ABT exists, additional RCTs transfusing non-buffy-coat-reduced RBCs to the treatment arm should be conducted.

Blood Transfusion↗

Leucocyte depletion during cardiac surgery: a comparison of different filtration strategies.

The results of leucocyte filtration during cardiac surgery are conflicting. This may be due to timing and duration of the filtration procedure, and to flow and pressure conditions in the filter. Therefore, we prospectively compared three major leucocyte filtration strategies in cardiac surgical patients. Forty patients were randomly divided into four groups. Group I: leucofiltration of arterial blood throughout cardiopulmonary bypass (CPB) (associated with high-flow and pressure gradients), Group II: leucofiltration of a part of the venous return blood in the rewarming phase during CPB (associated with intermediate flow, but high pressure), Group III: leucofiltration of residual heart-lung machine blood during transfusion into the patient after CPB (associated with low flow and low pressure), Group IV: control group without leucofiltration. We measured circulating leucocyte counts, plasma elastase levels and arterial blood oxygenation. Filters were postoperatively examined using scanning electronmicroscopy (SEM). Leucocyte counts increased over time and oxygenation decreased in all groups, without significant differences between the groups. SEM demonstrated extensive protein deposits and damaged leucocytes in the deeper layers of the filters from Group I. This was not observed in the filters from Group III. The postoperative plasma elastase levels increased in Groups II and IV and decreased in Groups I and III. In conclusion, we could not demonstrate a clinical difference among the three leucocyte depletion strategies. However, our laboratory results suggest that leucocyte filtration at low flow and pressure conditions is associated with less leucocyte damage and less release of elastase.

Aged↗

[Subareolar injection of 99m-Tc sulfur colloid for sentinel nodes identification in multifocal invasive breast cancer].

The objective were to study the relevance of the subareolar injection for sentinel node [SN] detection in multiple foci breast cancer. Seventy-nine patients with infiltrative breast carcinoma (diagnosed pre-operatively by core biopsy) and a mean age of 55 (31-78) years were enrolled. All patients were free of previous homolateral surgery, chemotherapy, locoregional radiotherapy or prevalent axillary lymph node. Using four 0.1 ml injections of 1.8 MBq, the technetium-99m 100 nm filtered sulfur colloid was injected by subareolar way (group I) in 16 cases of radiologically cancer with multiple invasive foci and 31 cases of radiologically unifocal cancer, and by peritumoral way (group II) in 32 cases of radiologically unifocal cancer. Scintigrams were obtained 2 to 4 hours after the injections and radioactive nodes were detected peroperatively 18 hours after the injection by intraoperative detection probe. Individual removal of all radioactive nodes was followed by axillary dissection at levels I and II of Berg including Rotter area control. All sentinel nodes were submitted to standard histopathological analysis on serial sections at 500 mu intervals completed by immunohistochemistry for cytokeratin on negative SN. SN were detected by scintigrams in 85% and 88% of the cases of group I and group II respectively, but in 98% and 97% of the cases of respectively both groups by intraoperative probe. Group I was composed of 69% ductal, 22% lobular and 9% tubular carcinomas, and group II of 87% ductal, 10% lobular and 3% tubular carcinomas. Seven and 5 radiologically unifocal tumors were in fact with multiple invasive foci at histology in groups I and II respectively. The complete scintigraphic procedure permitted the detection of a mean number of 2.7 (1-7) SN in group I and 2.3 (1-4) in group II (NS). In group I, the SN were metastatic in 22 patients (48%), 15 of them with the metastases being restricted to the SN, whereas in group II, the SN were metastatic in 9 patients (28%), 5 of them with the positivity restricted to the SN. No false negative result (SN negative and other axillary nodes positive) was observed in group I and only one false negative result in group II which was related to a cancer with histological multiple invasive foci. Sensitivities were 100% and 90%, and negative predictive values were 100% and 95%, for groups I and II respectively. Subareolar injection of radiocolloid allows identification of SN in cases of unifocal and multiple cancer. The mean number of SN detected by the subareolar method is not significantly different, although higher, to that detected by peritumoral injection.

Adenocarcinoma↗

The risk profile of glaucoma filtration surgery.

Glaucoma surgery has evolved over the past 30 years from the full-thickness procedure to the guarded filtration procedure. However, many of the risks and complications attendant with the full-thickness procedure, including endophthalmitis, hypotony, cataract progression, and filtration failure, continue to plague the glaucoma surgeon performing the guarded filtration procedure, although at lower incidences. With proper modification of technique, such as with postoperative bleb titration and use of adjunctive antifibrotic therapy based on prognosticators for failure, the success rates of trabeculectomy reoperations can approach those of primary trabeculectomy. Such risk factors for failure include African-American race, higher preoperative intraocular pressures, previously failed filters, younger age, and uveitic and neovascular glaucomas. In this paper, we review a number of studies that analyze the risks, complications, and long-term results of glaucoma filtration surgery and discuss different surgical recommendations based on risk factors for failure as well as for performing concomitant cataract and glaucoma surgery.

Glaucoma↗

Musculoskeletal and adipose tissue hydatidosis based on the iatrogenic spreading of cystic fluid during surgery: report of a case.

Hydatidosis or echinococcosis is a parasitic disease caused by Echinococcus granulosus or E. multilocularis, which forms cysts in the liver and lung after penetrating the duodenal mucosa and entering the portal circulation. The liver and lung act as a filter but some embryos enter the general circulation and disseminate throughout the body. Musculoskeletal involvement is a rare manifestation of hydatidosis, which is usually reported to affect a single muscle. We report here a rare case of a 68-year-old man with widespread hydatidosis of the retroperitoneum and the subcutaneous adipose tissue, and with multiple muscle involvement in the absence of liver, lung, and spleen involvement. The patient underwent surgical excision of a subcutaneous hydatid cyst 7 years earlier. It is likely that the large dissemination of parasites resulted from accidental rupture of the primary focus during surgery with consequent release and spreading of scolices via lymphatics.

Adipose Tissue↗

Radiation dose vs. image quality for low-dose CT protocols of the head for maxillofacial surgery and oral implant planning.

The goal of this study was to determine the acquisition parameters for a low-dose multi-slice CT protocol and to compare the effective dose and the image quality of this low-dose protocol with the image quality of a clinical multi-slice CT protocol, routinely used for visualisation of the head. The low-dose protocol was derived from a clinical multi-slice CT protocol by lowering mA s and kV and increasing the pitch. The low-dose protocol yielded a dose reduction from 1.5 to 0.18 mSv for a multi-slice CT scan of the whole head, whereas noise in the low-dose CT images was increased. For bone segmentation, noise could be reduced by use of a non-linear edge preserving smoothing filter. Tests on ESP and skull phantom indicated that the accuracy of the measurements on low-dose CT is acceptable for image-based planning of maxillofacial and oral implant surgery, reducing the dose by a factor of 8.

Humans↗

Does leukodepletion during elective cardiac surgery really influence the overall clinical outcome?

AIM: We examined the impact of leukocyte filtration during the entire bypass time on postoperative leukocytosis, perioperative hemorrhage and overall clinical outcome in patients undergoing elective cardiac surgery. METHODS: Eighty patients who electively underwent cardiac surgery were randomly allocated to a leukocyte depletion group (n=40) or a control group (n=40). In patients of the leukocyte depletion group an arterial line filter with leukocyte depleting capacity (Pall LG6) was applied instead of a standard arterial line filter. White blood cells and platelet count were estimated preoperatively and at various times postoperatively. Postoperative clinical outcomes were also recorded. RESULTS: Repeated measure analysis of variance between groups showed that leukocyte counts were significantly lower in the depletion group postoperatively (p=0.005) whereas no difference was found in the platelet counts (p=0.37). The catecholamine dose required at the time of weaning from cardiopulmonary bypass and during the first 12 postoperative hours was found to be lower in the leukodepletion group (p=0.027 and p=0.021, respectively). Furthermore leukodepleted patients showed a transient improvement in the oxygenation index (p=0.029) and a shorter period of mechanical ventilation (p<0.001). The incidences of postoperative complications were similar between the groups. No difference was observed in regard to postoperative blood loss (p=0.821) and amount of packed red blood cells required for transfusion during the first 24 hours (p=0.846). The duration of intensive care unit stay and of hospitalization were similar between the groups. CONCLUSION: Leukocyte depletion contributes to early postoperative improvement in heart and lung function but does not influence significantly the overall clinical outcome of patients undergoing elective cardiac surgery.

Cardiac Surgical Procedures↗

Light energy, cataract surgery, and progression of age-related macular degeneration.

PURPOSE OF REVIEW: Some studies suggest an association between light exposure and increased risk of advanced age-related macular degeneration. The natural lens serves as a barrier to some of the higher energy light rays. There is some concern that cataract surgery may be contributing to the increase in prevalence of age-related macular degeneration. RECENT FINDINGS: It has been shown that blue light absorption by retinal pigment epithelium results in free radical formation, leading to cellular injury, and that blue filters can reduce this rate of cell death. Other studies have shown a tendency for pseudophakic eyes to progress to the wet form of age-related macular degeneration more so than their fellow eyes. SUMMARY: Currently there is no conclusive evidence to support a relation between progression of age-related macular degeneration and cataract surgery. Given that nearly two million cataract extractions are performed yearly, a large randomized controlled study is required to prove or disprove the ability of tinted intraocular lenses to aid in preventing the progression of age-related macular degeneration.

Cataract Extraction↗

EEG changes during cardiopulmonary bypass surgery and postoperative neuropsychological deficit: the effect of bubble and membrane oxygenators.

OBJECTIVE: Quantitative electroencephalography was used during cardiopulmonary bypass surgery to determine the point in time of most neuronal functional change which may result in postoperative neuropsychological deficit. It was also used to determine any relationship between quantitative electroencephalography changes and type of oxygenator used in surgery. METHODS: We studied 61 coronary artery bypass graft patients. Anaesthesia included thiopental, fentanyl and N2O. Surgery was performed with hypothermic bypass (28 degrees C), arterial pressure of 50-70 mmHg, and alpha-stat, using bubble (Harvey 1700), or membrane (Cobe CML) oxygenators, both with arterial line filters (Pall 40 microns). RESULTS: The main finding was a significant increase in delta power at the end of perfusion (P < 0.01), which showed a positive association with delta power before the start of perfusion. Marked quantitative electroencephalography change at the end of perfusion was not related to systemic hypotension, temperature, type of oxygenator, bypass time, or patient age. Intraoperative quantitative electroencephalography changes found in most patients were transient and could not be related to postoperative cerebral function. However, 16 of the 18 patients who had neuropsychological deficit 2 months after surgery, also had a significant quantitative electroencephalography change at the end of perfusion. CONCLUSIONS: While no difference in anaesthetic technique was found between patients, the variation in quantitative electroencephalography power before perfusion may indicate a difference in individual response to anaesthetic. Usefulness of quantitative electroencephalography to predict postoperative cerebral functional deficit remains doubtful.

Aged↗

A mathematical analysis of haemorheologic factors during cardiopulmonary bypass for congenital heart disease.

Rheologic properties of blood are impaired by cardiac surgery using cardiopulmonary bypass. This study was set out to establish a mathematical model in order to assess seven known haemorheologic factors and evaluate their degrees of influence on blood rheology in cardiopulmonary bypass. Sixteen patients undergoing elective congenital cardiac surgery were studied. High shear blood viscosity, low shear blood viscosity, haematocrit, red blood cell filtration rate, red blood cell electrophoresis time, plasma viscosity and fibrinogen were monitored. The method for mathematical calculation was the stepwise regression analysis. The results showed that both high shear and low shear blood viscosity were mainly influenced by haematocrit and plasma viscosity. Red blood cell filterability contributed more than red blood cell electrophoresis time for low shear blood viscosity. The mathematical model was re-tested statistically and demonstrated that the selected factors in the model represented approximately 75% of rheologic changes during the surgery. Therefore, this mathematical analysis can be used to estimate the role of various possible haemorheologic factors and evaluate cardiopulmonary bypass techniques and therapeutic interventions.

Adolescent↗

[Economical analyses in interventional radiology].

Considerations about the relation between benefit and expenses are also gaining increasing importance in interventional radiology. This review aims at providing a survey about the published data concerning economical analyses of some of the more frequently employed interventions in radiology excluding neuroradiological and coronary interventions. Because of the relative scarcity of literature in this field, all identified articles (n = 46) were included without selection for methodological quality. For a number of radiological interventions the cost-effectiveness has already been demonstrated, e. g., PTA of femoropopliteal and iliac artery stenoses, stenting of renal artery stenoses, placement of vena-cava filters, as well as metal stents in malignant biliary and esophageal obstructions. Conflicting data exist for the treatment of abdominal aortic aneurysms. So far, no analysis could be found that directly compares bypass surgery versus PTA + stent in iliac arteries.

Angioplasty, Balloon↗

Surgical wound leaks associated with sodium hyaluronate (Healon).

Sodium hyaluronate (Healon) is an ideal material for protecting the cornea during intraocular lens implantation and protecting donor corneal material during corneal transplantation. Although it has been advocated for maintaining filtering blebs during trabeculectomy and as a vitreous replacement, its main benefit to ophthalmic surgeons is its protection of the cornea during anterior segment surgery.

Adult↗

Local delivery of chemotherapy: a supplement to existing cancer treatments. A case for surgical pastes and coated stents.

Local application or direct tumor injection of chemotherapeutic drugs has been proposed as a method by which local drug concentrations can be maximized in the immediate tumor environment while systemic exposure and non-target organ toxicity is minimized. Multiple opportunities are available to combine local drug delivery with widely practised, existing medical and surgical therapies. Surgical interventions, including both open and laparoscopic procedures, allow the physician to directly visualize and manipulate pathological tissues. Intraoperative placement of implantable therapeutic compounds (barriers to prevent adhesions, sustained-release antibiotics, tissue 'glues' and hemostatic agents) at or near the disease site is increasingly common in surgical practice. Less invasive therapies assisted by diagnostic imaging (fluoroscopy, ultrasound, CT and MRI scanning) have made accurate needle or catheter placement for drainage (abscesses, cysts, obstructions), injection (contrast media, pharmacological agents, embolic agents) and therapeutic purposes (endoluminal stents, venous filters) widely practised interventional medical procedures. This article describes a chemotherapeutic polymer-based paste we have developed for application at the time of surgery to reduce local recurrence of disease at tumor resection sites and a chemotherapeutic polymer-coated stent for use in the palliative management of malignant obstruction to improve the effective lifespan of the device (e.g., esophageal, biliary, prostate, and pulmonary disease). Despite the growth of local therapy in other disease states, regional cytotoxic drug therapy has not been widely deployed in the management of malignancy due to a clinical bias that local therapy will have limited utility in what is considered to be a systemic disease. In the above manner, local drug delivery could be incorporated into therapeutic protocols designed to enhance, not replace, the efficacy of existing treatment options.

Journal Article↗