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PubMed1998

Technique and outcome of combined phacoemulsification and trabeculectomy.

The efficacy of combined surgery for the treatment of concurrent glaucoma and cataract has long been under scrutiny. Comparisons between sequential surgery and combined procedures have shown mixed results, and current guidelines have been drawn for the indication of combined surgery. The evolution of combined triple surgery--cataract extraction, intraocular lens implantation, and filtering procedure--has evolved from planned extracapsular cataract extraction to small-incision phacoemulsification. The improvements of phacoemulsification over extracapsular surgery have naturally given rise to improvements in the results of combined procedures; good outcomes in both intraocular pressure control and visual acuity have been reported along with low complication rates. The techniques of combined phacoemulsification-trabeculectomy are under continual development as new sutureless incisions, filtration procedures, and antimetabolite use are studied. The results of numerous studies show that the combined procedure is an effective method of treatment of glaucoma and cataract. This review examines various recent aspects of the combined procedure, phacoemulsification-trabeculectomy, antimetabolites, results and complications, as well as current developments of new techniques. In addition, we review studies on combined cataract extraction and trabeculectomy, including older literature on planned extracapsular extraction plus trabeculectomy as well as newer studies on phacoemulsification-trabeculectomy.

Antimetabolites↗
PubMed1985

Factors affecting pseudophakic cystoid mascular edema: five randomized trials.

We summarize the findings of five randomized prospective, controlled studies that evaluated the following factors associated with the development of cystoid macular edema (CME) following cataract surgery: ultraviolet (UV) light from the operating microscope; postoperative UV light exposure; primary capsulotomy; retrobulbar hyaluronidase; and prostaglandin synthesis in the eye. The following were the major findings: (1) The presence of a UV-light filter on the operating microscope during cataract surgery made no statistically significant difference in the early postoperative (two to six months) angiographic incidence of CME or the visual outcome. (2) A UV-filtering posterior chamber intraocular lens (IOL) resulted in a statistically significant decrease in the early postoperative incidence of angiographic CME in postcataract-surgery patients but did not affect visual acuity. (3) Patients receiving primary capsulotomy during extracapsular cataract surgery showed a statistically significant higher incidence of early postoperative angiographic CME than did patients with an intact posterior capsule. Again there was no difference in visual acuity. (4) The addition of hyaluronidase to the retrobulbar anesthetic injection made no significant difference in the CME rate or postoperative visual results of patients undergoing extracapsular cataract surgery. (5) Patients undergoing IOL implant surgery who received topical indomethacin before surgery and for nine months postoperatively to inhibit prostaglandin synthesis in the eye showed a statistically significant lower incidence of early postoperative angiographic CME than did placebo-treated patients, but there was no significant difference between the two groups in postoperative visual acuity.

Cataract Extraction↗
PubMed1996

Slit-lamp needle revision of failed filtering blebs using mitomycin C.

PURPOSE: The purpose of the study is to determine the efficacy and safety of Mitomycin C (MMC) augmented slit-lamp needle revision of failed filtration surgery. METHODS: The authors retrospectively reviewed the charts of 62 patients (62 eyes) (age, 72 +/- 15 years) with failed filtration surgery who underwent needle revision using MMC. A mixture of 0.01 ml of MMC (0.4 mg/ml) and 0.02 ml of bupivacaine with epinephrine was injected subconjunctivally. Twenty to 30 minutes later, a 30-gauge needle was used to perforate the area of subconjunctival fibrosis and re-establish flow. RESULTS: Overall, 118 needing procedures (mean, 1.9 +/- 1.4 revisions per eye; range, 1-7) were performed on 62 eyes (mean follow-up, 9.9 +/- 3.7 months; range, 4.5-20.1 months). Thirty-six patients (58.1%) were needled once and 26 patients (41.9%) underwent more than 1 needling procedure. Intraocular pressure decreased from 24.1 +/- 6.4 mmHg (range, 18-44) before surgery to 11.5 +/- 4.8 mmHg (range, 1-26) at last follow-up (P = 5.51 x 10(-21)). Antiglaucoma medications decreased from 1.6 +/- 1.0 to 0.3 +/- 0.6 (P = 3.8 x 10(-14)). Successful single-needling procedure was highly correlated with race (white) and past conventional glaucoma filtration surgery of more than 4 years. Complications included serous choroidal detachment (10 eyes), suprachoroidal hemorrhage (1 eye), bleb leak (5 eyes), iris blocking sclerostomy (2 eyes), hyphema (2 eyes), corneal abrasion (2 eyes), and hypotony (1 eye). CONCLUSION: Mitomycin needle revision appears to be an extremely effective way to revive failed filtration surgery. The incidence of complications compares favorably to trabeculectomy with MMC.

Adult↗
PubMed2000

Detection of artifacts in monitored trends in intensive care.

In intensive care, decision-making is often based on trend analysis of physiological parameters. Artifact detection is a pre-requisite for interpretation of trends both for clinical and research purposes. In this study, we developed and tested three methods of artifact detection in physiological data (systolic, mean and diastolic artery and pulmonary artery pressures, central venous pressure, and peripheral temperature) using pre-filtered physiological signals (2-min median filtering) from 41 patients after cardiac surgery. These methods were: (1) the Rosner statistic; (2) slope detection with rules; and (3) comparison with a running median (median detection). After tuning the methods using data from 20 randomly chosen patients, the methods were tested using the data from the remaining patients. The results were compared with those obtained by manual identification of artifacts by three senior intensive care unit physicians. Out of an average of 22,480 data points for each variable, the three observers labelled 0.98% (220 data points) as artifacts. The inter-observer agreement was good. The average (range) sensitivity for artifact detection in all variables in the test database was 66% (33-92%) for the Rosner statistic, 64% (24-98%) for slope detection and 72% (41-98%) for median detection. All methods had a high specificity (> or = 94%). Slope detection had the highest mean positive prediction rate (53%; 21-85%). When the performance was measured by the cost function, slope detection and running median performed equally well and were superior to Rosner statistics for systemic arterial and central venous pressure and peripheral temperature. None of the methods produced acceptable results for pulmonary artery pressures. We conclude that median filtering of physiological variables is effective in removing artifacts. In post-operative cardiac surgery patients, the remaining artifacts are difficult to detect among physiological and pathophysiological changes. This makes large databases for tuning artifact algorithms mandatory. Despite these limitations, the performance of running median and slope detection were good in selected physiological variables.

Algorithms↗
PubMedDate not supplied

Activation of plasma components by leukocyte removal filters.

The technique of leukocyte filtration has been introduced into cardiac surgery to reduce leukocyte mediated reperfusion injury. When autologous whole blood (WB) is used as filtrate, it is more likely to be activated by the filter material than are banked red blood cell concentrates (RCC), because of its richness in plasma components. This study was designed to compare the activation of plasma components during leukocyte filtration from WB (n = 10) taken from the heart-lung machine, with RCC (n = 10) obtained from the blood bank. Leukocyte filters made from either cellulose acetate or polyester were used. Blood samples were taken simultaneously from the inlet and outlet of the filter after filtration of either 700 ml of WB or 350 ml of RCC. Results indicated that the complement cascade was activated, as reflected by the increase of C3a and C5a during filtration of WB by filters made from cellulose acetate. In contrast, there was no significant increase of C3a and C5a during filtration of RCC. The clotting system, indicated by fibrinopeptide A, and the fibrinolytic system, indicated by fibrinogen degradation products, were not activated during leukocyte filtration. These data suggest that it is the WB taken from the heart-lung machine rather than the RCC from the blood bank that is being activated during leukocyte filtration. Thus, careful selection of filter material is important for leukocyte filtration of autologous whole blood during cardiac surgery.

Cellulose↗
PubMed2005

[Surgical stratification of renal carcinoma with extension into inferior vena cava].

Renal cell carcinoma with inferior vena cava thrombus is relatively uncommon and complicates radical nefrectomy. During the past twenty years our hospital have substantially contributed to the surgical stratification of renal cell carcinoma with extension into inferior vena cava through different techniques. The reason for this article is to discuss the mote efficient and appropiate surgical technique for this pathology. We believe that the diagnosis of vena caval invasion and level of tumoral extension is based on radiological examinations and it is crucial for the success of the surgery. We consider that the use of vena caval filter applied preoperatively could prevent the risk of thromboembolism during and after the surgery. The use of prosthetic grafts is unusual, because the long standing obstruction caused by the tumor thrombus will develope extensive collateral circulation which works as a natural veno-venous bypass. Finally, we try to avoid the use of veno-venous and cardiopulmonar bypass with or without complete hypothermic circulatory arrest due to the high association with adverse outcomes and mortality.

Carcinoma, Renal Cell↗
PubMed1993

Ocular hypotony and choroidal effusion following bleb needling.

A choroidal effusion, hypotony, and a shallow anterior chamber developed in a patient following a transconjunctival needling revision of an encapsulated filtering bleb. While choroidal effusions occur frequently following filtration surgery, to our knowledge, this complication has not been previously reported following a filtering bleb needle revision.

Choroid Diseases↗
PubMed1988

The effect of arterial filtration on reduction of gaseous microemboli in the middle cerebral artery during cardiopulmonary bypass.

Noninvasive in vivo detection of gaseous microemboli in the middle cerebral artery, by transcranial Doppler ultrasound, was used to determine the effect of filtration in the arterial catheter using 25- and 40-microns filters and bubble oxygenators in patients undergoing cardiopulmonary bypass surgery. Eighteen patients undergoing coronary artery bypass surgery were studied using a closed cardiac (unvented heart) model. Group 1 patients (no filters) had the highest incidence of gaseous microemboli, as indicated by the ultrasound microemboli index, at both high and low oxygen flow rates. Group 2 patients (40-microns filters) had a significantly lower microemboli index, particularly at low oxygen flow rates (t = 4.9, p less than 0.001). The 25-microns group patients had the lowest values of all. No microemboli were detected at low oxygen flow rates, and microemboli were detected in only 0.1% of the samples at high oxygen flow rates. Additionally, observations on vented hearts in 3 patients undergoing cardiac valve surgery indicate that the origin of gaseous microemboli may be air trapped inside the heart.

Cardiopulmonary Bypass↗
PubMed1998

Development of a fluorescein operative microscope for use during malignant glioma surgery: a technical note and preliminary report.

BACKGROUND: Fluorescein has been used in the field of neurosurgery; however, fluorescein enhancement or contrast proved to be inadequate because of a lack of appropriate light sources or filters. A new operative microscope system, in which the microscope itself is equipped with excitation and barrier filters, and the application of this system to surgery for malignant glioma are reported. METHODS: BP 450-490, a glass interference filter used as the excitation filter for the light source optical system, and a Kodak Wratten No. 12 filter used as the barrier filter for the microscope optical system, were incorporated in the operative microscope. A switching apparatus was devised so that filters could be inserted instantly when fluorescence was to be observed. Ten cases in which the location of malignant glioma was enhanced by computed tomography (CT) or magnetic resonance imaging (MRI) were selected for this study. After incision of the dura mater, 8 mg/Kg body weight of fluorescein Na was injected intravenously. Tumor removal was begun some 20 min after the injection with the aid of this newly developed fluorescein operative microscope system. RESULTS: Fluorescence enhancement and contrast were remarkable when this system was used. It enabled surgical maneuvering while viewing the fluorescent image of objects. The boundaries between the tumor areas enhanced by CT or MRI and the surrounding brain could be clearly distinguished in the fluorescent image; the tumor was totally removed, except for deep lesions, without any neurological deterioration. When the tumor was relatively hard, the area surrounding the tumor was aspirated with a cavitron ultrasonic surgical aspirator; as a result, the tumor could be removed en bloc; otherwise, the fluorescent tumor was removed piece by piece. CONCLUSIONS: This system provides adequate fluorescent enhancement and contrast and is useful for observing intravenously injected fluorescein during an operation. Though long-term follow-up of such cases is needed, the conditions of our patients immediately after surgery for malignant glioma were satisfactory. These results suggest that our fluorescein operative microscope system is highly effective in surgery for malignant glioma.

Adult↗
PubMed1995

[Collagen synthetic activity following filtration surgery in rabbits].

We evaluated collagen synthetic activity, which plays an important role in wound healing, following experimental filtration surgery in rabbits. Collagen synthetic activity was measured by immunohistochemistry for prolyl 4-hydroxylase beta-subunit and type I procollagen. Trabeculectomy was performed on albino rabbit eyes, with the filtering site harvested on postoperative days 1, 4, 7, 14, and 28. Samples were fixed with 10% buffered formalin for 12 hours and prepared for paraffin section, and each antigen was detected in filtering site tissue using avidin-biotinylated peroxidase complex. Immunoreaction of prolyl 4-hydroxylase beta-subunit or type I procollagen increased from day 4 to 14 and markedly decreased at day 28. These findings show that prolyl 4-hydroxylase and type I procollagen are markedly produced almost simultaneously, and collagen synthetic activity following filtration surgery continues for over 14 days in the process of wound healing.

Animals↗
PubMed1994

Bubbles in the bleb--troubles in the bleb? Molteno implant and intraocular tamponade with silicone oil in an aphakic patient.

A 14-year-old aphakic girl who had had previous bilateral glaucoma surgery with a Molteno implant underwent pars plana vitrectomy and silicone-oil tamponade for proliferative-vitreoretinopathy retinal detachment in both eyes. The filtering bleb of the left eye was functional for 5 months before becoming available for histologic examination. We found numerous foreign-body granulomas coating the inner surface of the bleb, as well as intracellular and extracellular deposits of emulsified silicone oil in the wall of the bleb. In the fellow eye, the filtering bleb remained functional despite repeated vitreous surgery with silicone oil. Filtration in aphakic eyes with previous Molteno surgery and silicone-oil tamponade after vitrectomy may continue normally for a prolonged period of time, although emulsified oil droplets likely will have accumulated in the bleb and become incorporated in its fibrous capsule.

Adolescent↗
PubMed2003

Photodynamic modulation of wound healing in glaucoma filtration surgery.

AIM: To report a clinical pilot study investigating photodynamic therapy (PDT) in combination with glaucoma filtration surgery. BCECF-AM was used as the photosensitising substance. The clinical safety and tolerability of BCECF-AM, and its efficacy in controlling postoperative intraocular pressure (IOP) were assessed. METHODS: Before trabeculectomy (TE), 42 consecutive eyes of 36 glaucoma patients received one subconjunctival injection of 80 micro g BCECF-AM (2,7,-bis- (2-carboxyethyl) -5- (and-6) -carboxy-fluorescein, acetoxymethyl-ester) followed by an intraoperative illumination with blue light (lambda = 450-490 nm) for 8 minutes. Antifibrotic efficacy was established as postoperative IOP reduction of >20% and/or an IOP constantly < 21 mm Hg without antiglaucomatous medication. Follow up of the filtering bleb was documented by slit lamp examination. RESULTS: Eyes had mean 1.1 preoperative surgical interventions (filtration and non-filtration glaucoma surgery). Mean preoperative IOP was 31.6 (SD 9.7) mm Hg. Patients were followed for mean 496 days (range 3.5-31.8 months). Of the 42 eyes, 25 eyes had an IOP decreased to 15.8 (3.4) mm Hg without medication (complete success: 59.5%; p<0.001; t test). Seven eyes showed good IOP reduction < 21 mm Hg under topical antiglaucomatous medication (qualified success: 16.7%). 10 eyes failed because of scarring within 2-67 weeks (23.8%). Clinical follow up examinations revealed no local toxicity, no uveitis, and no endophthalmitis. CONCLUSIONS: This method is a new approach in modulating postoperative wound healing in human eyes undergoing glaucoma filtration surgery. The data of the first human eyes combining TE with PDT underline the clinical safety of this method and its possible potential to prolong bleb survival.

Adult↗
PubMed1996

The microbiologic effect of gas filtration.

BACKGROUND: Air and expansile gases commonly are injected into the eye in both vitreoretinal surgery and anterior segment surgery. Although the halogenated gases are filtered routinely before injection, air often is not prepared in this manner. This study was designed to investigate the effect of filtration on the microbiology of gas mixtures. METHODS: Two separate studies were conducted, one examining medical grade perfluoropropane gas (C3F8), and the other evaluating air collected from an ophthalmic operating room or emergency room. Aliquots of air or gas were collected through a 0.22-micron filter before and after filtration. The filter discs were cultured for bacterial and fungal organisms. RESULTS: Of 514 samples collected, none grew either bacterial or fungal organisms. There was no difference with regard to recovered microbes between filtered and unfiltered air or C3F8, nor was there a difference between operating room air and emergency room air. Positive controls using aerosolized microorganisms yielded heavy growth. CONCLUSION: Based on results obtained in this study and available information on the concentration of airborne microbes, the microbiologic effect of gas filtration is of little significance for volumes routinely injected in ophthalmic surgery.

Air↗
PubMed2004

Postoperative Level 1 anticoagulation therapy and spinal surgery: practical guidelines for management.

OBJECT: The authors conducted a review of the literature to establish reasonable practical guidelines for the management of complications in patients who have undergone recent spinal surgery and who require Level 1 anticoagulation therapy. METHODS: A MEDLINE (PubMed) literature search was performed using the key words "postoperative anticoagulation," "spinal surgery," and "postoperative epidural hematoma," for articles published between 1990 and 2004. The search yielded 148 articles, which were then further screened for relevance and classified according to level-of-evidence guidelines established by the American Association of Neurological Surgeons/Congress of Neurological Surgeons joint committee for spinal cord injury. A total of 12 relevant articles were reviewed. There were no relevant articles meeting Class 1 standards of evidence, two met Class 2 evidence standards (one was a nonrandomized cohort study, the other was case-controlled), and the remaining 10 articles contained Class 3 evidence. CONCLUSIONS: There are insufficient data to establish evidence-based guidelines for the use of Level 1 heparin or an equivalent anticoagulation protocol in patients who have recently undergone spinal surgery. Nevertheless, a search of the limited peer-reviewed literature on the subject indicates that there is an anecdotally high risk of complications in patients who have undergone spinal surgery and in whom a Level 1 or equivalent heparin protocol is administered. It therefore seems most prudent to arrange for placement of a vena cava filter in patients who have undergone spinal surgery and in whom a pulmonary embolus is found postoperatively. In patients who undergo spinal surgery and who require heparinization therapy for myocardial ischemia or infarction, the use of frequent neurological examinations in conjunction with anticoagulation therapy seems to be the only reasonable option.

Anticoagulants↗
PubMed2006

A prospective clinical study of cerebral microemboli and neuropsychological outcome comparing vent-line and auto-venting arterial line filters: both filters are equally safe.

INTRODUCTION: Microemboli are the main implicated cause of neuropsychological (NP) impairment after cardiac surgery. This prospective clinical trial compared the effect of an auto-venting arterial line filter on intraoperative cerebral microemboli and NP outcome compared to an arterial line filter with a vent line, in patients undergoing elective coronary artery bypass graft (CABG) surgery. METHODS: One hundred and ten patients received either an Avecor Affinity (n =73) or Pall AV-6 (n =37) control filter. Cerebral microemboli during cardiopulmonary bypass were recorded by transcranial Doppler monitoring of the right middle cerebral artery. Evidence of cerebral impairment was obtained by comparing patients' performance in a NP test battery (nine tests) administered 6-8 weeks postoperatively with their preoperative scores. RESULTS: During cardiopulmonary bypass, the median number and range of microemboli were 67 (5-846) and 55 (2-773) for the Avecor and AV-6 groups, respectively (p = 0.47). There was no difference in NP outcome. CONCLUSION: There is no difference in the filtering ability of vent-line and auto-vent filters as assessed by cerebral microemboli. This, together with the similar NP outcome, suggests that both types of filter are equally safe for clinical use.

Aged↗
PubMed2003

Septuagenarian's phenotype leads to ascertainment of familial MYOC gene mutation.

PURPOSE: To report a family with a myocilin (MYOC) gene mutation ascertained on the basis of the phenotype of the 71-year-old proband with juvenile-onset primary open-angle glaucoma (JOAG). PATIENTS AND METHODS: A thorough patient history of the proband and review of medical records revealed that a filtering procedure performed 50 years before had controlled the intraocular pressure (IOP) and prevented optic disc damage and visual field loss until the bleb failed after cataract surgery. Patient characteristics and history led to suspicion of a mutation in the MYOC gene. Mutation screening and clinical evaluation of the proband and family members were undertaken. RESULTS: A Val426Phe mutation was found in the JOAG proband and in 3 other blood relatives with glaucoma. The mutation was not present in unaffected relatives. CONCLUSIONS: A functioning filtering procedure performed 50 years before the current study was all that was needed to prevent glaucomatous damage and control IOP in the proband. Once the bleb failed, increased IOP led to damage in a relatively brief period of time. Although not every JOAG patient has the MYOC mutation, there is a somewhat typical MYOC phenotype that may predict an increased chance of harboring a MYOC mutation. Use of such phenotype information in evaluating whether to screen older patients can lead to identification of families at risk for open-angle glaucoma.

Adolescent↗
PubMed1996

The potential for reintroduction of tumor cells during intraoperative blood salvage: reduction of risk with use of the RC-400 leukocyte depletion filter.

OBJECTIVES: Intraoperative autotransfusion of shed blood is widely utilized in surgery. However, several studies have raised concern about the transmission of tumor cells during oncologic procedures. We compared the ability of a leukocyte depletion filter (RC-400; LDF) to a standard red blood cell filter (SBF) to remove tumor cells derived from urologic malignancies. METHODS: Cells were suspended in media and passed through a SBF or a LDF. The filtrate was evaluated for the presence of viable cells utilizing the trypan blue exclusion method as well as cell culture. In a second experiment, cells were suspended in fresh bovine blood and processed through a cell saver apparatus followed by filtration with either a SBF or a LDF. Aliquots were cultured after admixture with blood, after processing, and after filtration. RESULTS: The LDF was able to remove tumor cells completely, as demonstrated by both counting with the trypan blue exclusion test and by cell culture. In contrast, admixture with blood processing through the cell saver apparatus nor a standard red blood cell filter removed these cells. CONCLUSIONS: Tumor cells derived from urologic malignancies are easily removed with a LDF but not with a SBF. Filtration of blood salvaged at the time of uro-oncologic surgery with a LDF but not with a SBF reduces the potential for reinfusion of viable tumor cells.

Blood Transfusion, Autologous↗