Amino-acid levels in subretinal and vitreous fluid of patients with retinal detachment.

PURPOSE: To compare the concentration of amino acids in subretinal and vitreous fluid of patients with primary rhegmatogenous retinal detachment to that of control vitreous. METHODS: This prospective, observational study measured amino-acid levels in subretinal fluid of patients undergoing scleral buckle placement (n=20) and vitreous fluid in patients undergoing pars plana vitrectomy (n=5) for primary retinal detachment. Vitreous fluid from patients undergoing vitrectomy for macular hole (n=7) or epiretinal membrane (n=3) served as a control. Subretinal fluid and control vitreous were analysed using high-pressure liquid chromatography. Retinal detachment vitreous was analysed using capillary electrophoresis-laser-induced fluorescence. RESULTS: Mean levels of glutamate (27.0+/-1.7 microM), aspartate (4.1+/-4.0 microM), and glycine (44.1+/-31.0 microM) in subretinal fluid and glutamate (13.4+/-11.9 microM) in the vitreous were significantly elevated in retinal detachment compared to control vitreous. A significant, positive association was observed between levels of aspartate and glutamate in subretinal fluid (Spearman's correlation coefficient: 0.74, P<0.01). Mean arginine levels did not differ significantly between subretinal fluid and control vitreous. Levels of alanine, tyrosine, valine, isoleucine, leucine, and phenylalanine were significantly lower in subretinal fluid compared to control vitreous (all P<0.01). CONCLUSIONS: Glutamate levels in subretinal fluid and vitreous of patients with primary retinal detachment is significantly elevated in comparison to control vitreous. This finding lends further support to the hypothesis that elevated glutamate levels may result from ischaemia of the outer retina secondary to retinal detachment.

[Is it necessary to always treat the relapses of superficial bladder tumour at the moment of diagnosis? Preliminary communication]. / Es necesario resecar siempre las recidivas de los tumores vesicales superficiales en el momento del diagnostico? Comunicación preliminar.

OBJECTIVE: To assess the expectant management superficial recurrent bladder tumours. MATERIAL AND METHODS: Between Jan 1998 and Dec 2003, 112 patients were diagnosed of superficial bladder tumour. 13 patients were observed after the diagnosis of tumour relapse until the decision to perform a transurethral resection. We analysed the clinical and pathological features. The patients were controlled with flexible cystoscopy every 3 months approximately. Of the 13 patients we count 15 observation events, (2 times in 2 patients). The decision between to treat or continue with observation was based in changes of appearance, size or number of tumours and presence of hematuria. RESULTS: With a mean age of 74.6 years (47-91). The mean observation time was 5.76 months (3-71). In the group of tumours previous to the observation period, in 12 events (10 patients) that means 80% any progression in grade or stage was observed. In the other 3 events we observed progression in grade and stage in 2 and only stage in 1. In any case we observed progression to invasive bladder tumour neither upper urinary tract tumour. CONCLUSIONS: Due to the low risk of progression, we believe that immediate eradication is not always necessary, thus reducing the adverse impact of repeat resections.

A matched study of primary scleral buckle placement during repair of posterior segment open globe injuries.

AIMS: To compare the visual and anatomical outcomes of patients who underwent primary scleral buckle (SB) placement during posterior segment open globe repair with matched control patients who did not undergo primary SB placement. METHODS: Patients who underwent open globe repair alone or with SB placement at Duke University Eye Center (November 1994-September 1997) and the Massachusetts Eye and Ear Infirmary (July 1993-July 1997) were identified. 19 open globe patients who received primary SB placement were matched with control patients who did not receive a primary SB based on three important prognostic factors: (1) visual grade; (2) zone of injury; and (3) mechanism of injury. The outcomes of interest were: (1) visual outcome; (2) anatomical outcome; (3) subsequent retinal detachment (RD); and (4) number of subsequent surgeries. RESULTS: Baseline characteristics between the groups were similar. Patients who received primary SB placement had a better final visual grade (p = 0.02), logMAR vision (p = 0.007), and anatomical grade (p = 0.01) compared with control patients. Primary SB patients had an average final vision of 20/270, whereas control patients had an average final vision of hand movement. Primary SB placement also resulted in fewer subsequent RDs (26% versus 53%), but this difference did not reach statistical significance (p = 0.10). There were no complications associated with primary SB placement. CONCLUSION: Primary SB placement during posterior segment open globe repair may decrease the risk of subsequent RD and improve final visual and anatomical outcome.

Illuminated lens fixator for bimanual pars plana lensectomy.

Pars plana vitrectomy and lensectomy are effective methods for removing posteriorly dislocated lens material. We describe an illuminated nucleus fixator that assists in the removal of posteriorly dislocated lens fragments. We tested the efficacy of the illuminated nucleus fixator compared to a standard endoilluminator in removing lens nuclei from the vitreous cavity of a cadaveric eye model. Use of the illuminated nucleus fixator as compared to a standard endoilluminator significantly reduced the time needed to remove lens nuclei from the vitreous cavity. This instrument could penetrate and fixate lens nuclei and could safely stabilize small and intermediate-sized lens fragments against the activated fragmatome. Bimanual lensectomy using the illuminated nucleus fixator significantly shortens the surgical time needed to remove posteriorly dislocated lens fragments. Shortening the surgical time for lensectomy may minimize such complications as retinal tears, trauma, and phototoxicity.

Antithrombotic effect of ticlopidine in an experimental model of retinal vein occlusion.

PURPOSE: Ticlopidine inhibits adenosine diphosphate (ADP)-induced platelet aggregation and may be effective in patients with retinal vein occlusions (RVO). This study tests the efficacy of ticlopidine in an animal model of RVO. METHODS: Rose bengal-mediated argon laser photothrombosis of retinal veins was created in rabbits pretreated with oral ticlopidine, aspirin, or saline. The number of laser spots necessary to produce a partial or complete RVO was recorded and tabulated. RESULTS: Pretreatment with ticlopidine significantly increased the number of laser spots needed to produce a partial (P =.02), or a complete (P =.002) RVO as compared to the control group. Pretreatment with ticlopidine significantly increased the number of laser spots needed to produce a partial RVO (P =.02). Pretreatment with aspirin significantly increased the number of laser spots needed to produce a complete RVO (P =.002). CONCLUSION: Ticlopidine may be a useful antiplatelet agent for the treatment of patients with RVO. Patients treated with ticlopidine should be monitored for the possible development of hematologic disorders.

Primary scleral buckling in open-globe injury involving the posterior segment.

PURPOSE: To determine whether scleral buckle placement at the time of primary repair of open-globe injury of the posterior segment is beneficial. DESIGN: Retrospective, comparative, nonrandomized interventional study. PARTICIPANTS: One hundred twenty-five open-globe injuries treated at the Duke University Medical Center from June 1980 to May 1997. METHODS: Open-globe injuries were classified with the Open-globe Injury Classification. Eyes that had zone 2 and 3 injuries that had a primary buckle placed were compared with those that did not. MAIN OUTCOME MEASURES: Subsequent retinal detachment, visual outcome, and need for subsequent scleral buckling. RESULTS: The rate of retinal detachment and the visual outcome were similar in the two groups. More than half of those who did not have a primary buckle placed had subsequent scleral buckling surgery. CONCLUSIONS: Many open-globe injuries of the posterior segment require eventual scleral buckle. There may be a role for placement of a scleral buckle at the time of primary repair.

Postoperative complications of scleral buckling surgery.

The postoperative course of scleral buckling surgery can witness a host of untoward events, which may undo the anatomical success of retinal reattachment. Diligent preoperative identification of all retinal breaks and meticulous intraoperative technique will enhance the likelihood of a tranquil postoperative course.

Recurrent mixed germ cell-sex cord-stromal tumor of the ovary in an adult.

A 32-year-old woman underwent laparotomy and right salpingo-oophorectomy for a right adnexal mass. Examination of the specimen revealed a 77 g well-encapsulated tumor that was diagnosed as a mixed germ cell-sex cord-stromal tumor with annular tubules. Sixty-seven months after an uneventful recovery, a large recurrence was treated by total abdominal hysterectomy, left salpingo-oophorectomy, removal of peritoneal implants, lymphadenectomy, omentectomy, and chemotherapy. Histologically, the neoplasm was identical to the one found in the right ovary. To our knowledge, no similar case has been previously reported.

Regulation of the O-acetyl-L-serine(thiol)lyase activity in Monoraphidium braunii.

Total level of O-acetyl-L-serine(thiol)lyase (OASTL) activity observed in Monoraphidium braunii fed-repleted cells decreases up to 40% after 24 h the carbon source was removed from the culture; however, no significant change in the activity is observed in N-starved cells. On the other hand, sulfur starvation induces OASTL activity in M. braunii, which may increase 2.5-fold after 36 h. Normal intracellular level of the activity is restored when a sulfur source, such as sulfate, sulfite, L-cysteine, L-methionine or glutathione is added to the culture. The induction of the OASTL activity requires de novo synthesis of protein, and thus the presence in the culture of adequate carbon and nitrogen sources. The OASTL isoenzymes from M. braunii cells are differently affected by S-starvation.

In vivo photoactivation of caged-thrombin.

Aberrant ocular neovascularization is a major cause of blindness in the world. Abnormal blood vessels in the eye may produce corneal opacification, corneal transplant rejection, neovascular glaucoma, vitreous hemorrhage, traction retinal detachment, and subretinal scars from choroidal neovascular membranes (1-5). Light-induced clotting of blood within these abnormal vessels could provide a novel method for the ablation of deleterious neovascularization. Thrombin is a serine proteinase that participates in the final stages of the coagulation cascade. An inhibitor of thrombin, p-Amidinophenyl-(E)-4-diethylamino-2-hydroxy-alpha-methylcinnamate hydrochloride, MeCINN (1), covalently attaches to the active site serine hydroxyl, inhibiting or caging, the enzyme. Photolysis of the caged-thrombin in vitro causes a trans-cis isomerization of MeCINN which leads to regeneration of active enzyme and cleaving of fibrinogen into fibrin (6). Using a rabbit model of corneal neovascularization, we found that light at 366 nm safely and effectively photoactivates intravenous caged-thrombin and produces localized thrombosis in vivo. These results suggest that intravascular photoactivation of caged-thrombin could be used to occlude abnormal blood vessels in the human eye.

An immunocytochemical study of isolated human retinal Müller cells in culture.

BACKGROUND: We report a modified method for the isolation and propagation of adult human Müller cells in culture. METHODS: The retina of postmortem human eyes was mechanically dissociated and cultured. Using immunocytochemical techniques, these cells were stained with monoclonal antibodies specific for Müller cells, glial fibrillary acidic protein (GFAP), vimentin, glutamine synthetase (GS) and keratin. Transmission electron microscopy (TEM) was also performed. RESULTS: The dissociated and cultured cells expressed vimentin and GS, but not GFAP. At least 85% of these cells stained with a Müller cell-specific monoclonal antibody. Using TEM, flat cells containing 13-nm intermediate filaments and glycogen were identified. CONCLUSION: Human retinal Müller cells can be isolated and propagated in culture. Purified cell cultures are required for controlled studies of the normal physiology and pathologic responses of Müller cells.

Indocyanine green videoangiography after acute retinal pigment epithelial tears in age-related macular degeneration.

PURPOSE: To determine the features of combined fluorescein and indocyanine green videoangiography after acute retinal pigment epithelial tears associated with age-related macular degeneration. METHODS: We performed combined fluorescein and indocyanine green videoangiography in three eyes of three patients 2 days to 2 months after the development of tears of the retinal pigment epithelium. RESULTS: The area of exposed choroid in a retinal pigment epithelial tear shows intense hyperfluorescence in fluorescein videoangiography; in contrast, this area demonstrates near-normal choroidal fluorescence on an indocyanine green videoangiogram. The folded and retracted flap of retinal pigment epithelium in a retinal pigment epithelial tear discloses marked hypofluorescence on the fluorescein videoangiogram; in contrast, this flap of retinal pigment epithelium displays varying degrees of hyperfluorescence on the indocyanine green videoangiogram. CONCLUSIONS: The angiographic differences between fluorescein and indocyanine green result from the distinct biophysical properties of these two dyes as well as from the differential penetration of their fluorescence through such pigmented structures as retinal pigment epithelium. Compared with fluorescein videoangiography, indocyanine green videoangiography allows better visualization of choroidal neovascular membranes within the rolled-up and retracted flap of the retinal pigment epithelial tear.

Retinal distortion and cotton-wool spots associated with epiretinal membrane contraction.

PURPOSE AND BACKGROUND: Several articles on surgery for macular pucker have noted the presence of intraretinal white spots, presumably cotton-wool spots, associated with epiretinal membranes. It was proposed that membrane contraction and resultant nerve fiber layer distortion might lead to blockage of axoplasmic flow and thus a cotton-wool spot. To see whether the observations supported this concept, the authors studied patients with epiretinal membranes associated with intraretinal white spots involving the center of the fovea, where there are normally no retinal vessels and the only axons are in Henle fiber layer. METHODS: Four patients with epiretinal membranes associated with prominent areas of intraretinal whitening involving the center of the fovea were examined before and after surgery. Observations and measurements were made from projected fundus photographs. RESULTS: The intraretinal white spots, which appeared preoperatively to lie in the center of the fovea, proved to have been pulled in from more peripheral retina by the epiretinal membrane. These white areas were associated with surprisingly great distortion of the inner retina. Stretching of the inner retina seemed to play a larger role in the retinal distortion than full-thickness retinal folding. CONCLUSION: The appearance and time course of these intraretinal white lesions were consistent with cotton-wool spots caused by mechanical disruption of axonal flow. The marked retinal stretching and distortion of the innermost layers of the retina were the most striking findings in this study and also seemed consistent with the concept that membrane contraction and resultant nerve fiber layer distortion might lead to blockage of axoplasmic flow and thus a cotton-wool spot.

Steroid-induced visual recovery in fibrous dysplasia.

Fibrous dysplasia is a rare disorder of bone that may be associated with acute loss of vision. Surgical intervention is generally advocated and sometimes restores vision in these patients. We report a case of a patient with unilateral optic neuropathy from fibrous dysplasia who suffered two acute episodes of visual impairment. The first episode of vision loss was reversed by surgery and the second by corticosteroid treatment. A trial of corticosteroid therapy may be beneficial in cases of acute vision loss due to fibrous dysplasia.

Assessment of results of estrogen and progesterone receptor assays performed in a community hospital.

Approximately 1,000 assays for estrogen receptor (ER) in primary human breast tumors have been performed at St. Joseph's Hospital over a period of seven years; 700 of these included assays for progesterone receptor (PR). Based on the method of analysis (dextran-coated charcoal) and criteria for a positive result used for this survey, 80 percent of the primary tumors were ER-positive and 56 percent were PR-positive. In those cases where both assays were performed, 47.4 percent were ER-positive, PR-positive; 19.8 percent were ER-positive, PR-negative; 6.2 percent were ER-negative, PR-positive; and 26.6 percent were ER-negative, PR-negative. The mean concentration of ER increased with the advancing age of the patient; essentially the same relationship was observed for PR. The concentration of ER and PR was not directly dependent upon the degree of cellularity of the tumor. Lobular carcinoma and the mixed types containing ductal and lobular elements had the highest frequency of being positive for both steroid receptors, while medullary and papillary carcinomas were lowest. Three hundred and twenty-two cases had follow-up studies and were examined on the basis of the available information in the files of St. Joseph's Hospital Tumor Registry. A higher survival rate in patients with both ER and PR positivity became evident. In a community hospital setting, our data confirm the usefulness of estrogen and progesterone receptor assays in decisions of clinical management and considerations of prognosis in patients with mammary carcinoma.

Inverted papilloma of the renal pelvis. Cytologic features of ureteral washings.

A case of rare inverted papilloma of the renal pelvis with cytologic study of ureteral washings is described. Cytologic findings included increased numbers of urothelial cell clusters with mild degenerative changes. Although cytology was helpful in establishing the presence of a papillary transitional-cell lesion, histologic analysis following resection was required to distinguish between the possibilities of transitional-cell carcinoma and inverted papilloma.