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Dive into the research topics where George Alexandrakis is active.

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Featured researches published by George Alexandrakis.


Ophthalmology | 2000

Shifting trends in bacterial keratitis in South Florida and emerging resistance to fluoroquinolones

George Alexandrakis; Eduardo C. Alfonso; Darlene Miller

OBJECTIVE To study the distribution, current trends, and patterns of resistance to antimicrobial agents of bacterial keratitis isolates in South Florida. DESIGN Retrospective, observational, case series. PARTICIPANTS The microbiology records of all patients with bacterial keratitis seeking treatment at the Bascom Palmer Eye Institute from January 1, 1990 through December 31, 1998 were reviewed. MAIN OUTCOME MEASURES In vitro laboratory minimum inhibitory concentration testing of the corneal isolates to the fluoroquinolones (ofloxacin and ciprofloxacin) and to the aminoglycosides (tobramycin and gentamicin) was performed using the Vitek (Automatic Microbial System Biomerieux Vitek, Inc., Hazelwood, Missouri) method. RESULTS During this 9-year period, 2920 consecutive corneal cultures were obtained, and a pathogen was recovered in 1468 cultures (50%). The number of corneal ulcers scraped, positive cultures, recovered bacterial isolates, and ratio of gram-positive to gram-negative isolates per year remained approximately equal throughout the study period. Staphylococcus aureus and Pseudomonas aeruginosa represented 19.4% and 25.7%, respectively, of the total bacterial isolates during this period. However, we documented a gradual increase in the number of S. aureus keratitis isolates (29% of gram-positive organisms in 1990 versus 48% in 1998, P = 0.01) coupled with a decrease in the number of P. aeruginosa isolates (54% of gram-negative organisms in 1990 versus 46% in 1998). A decrease in the incidence of contact lens-associated keratitis and P. aeruginosa isolates in this group of patients was documented. Serratia marcescens and P. aeruginosa were most commonly isolated in contact lens-associated keratitis (18% each). There was increasing laboratory resistance of S. aureus keratitis isolates to the fluoroquinolones (11% in 1990 to 28% in 1998), but resistance patterns to the aminoglycosides remained unchanged. There was a three-fold increase in the percentage of resistant S. aureus isolates to fluoroquinolones between 1990 and 1994 and between 1995 and 1998. Both fluoroquinolones and aminoglycosides exhibited low in vitro effectiveness against P. aeruginosa throughout the study period. CONCLUSIONS The increased recovery of S. aureus keratitis isolates and decreased laboratory effectiveness against fluoroquinolones to these pathogens present an important therapeutic challenge.


American Journal of Ophthalmology | 2000

Combined pars plana vitrectomy and glaucoma drainage implant placement for refractory glaucoma

Ingrid U. Scott; George Alexandrakis; Harry W. Flynn; William E. Smiddy; Timothy G. Murray; Joyce C. Schiffman; Steven J. Gedde; Donald L. Budenz; Francisco Fantes; Richard K. Parrish

PURPOSE To report visual acuity and intraocular pressure outcomes among patients who have undergone combined pars plana vitrectomy and placement of a glaucoma drainage implant. METHODS The medical records of all patients who underwent combined pars plana vitrectomy and placement of a glaucoma drainage implant at the Bascom Palmer Eye Institute by one of the authors between January 1, 1990, and February 28, 1998, were reviewed. Forty patients (40 eyes) were identified, including 14 patients with neovascular glaucoma secondary to proliferative diabetic retinopathy or central retinal vein occlusion, 15 patients with other posterior segment disease, seven patients with secondary angle-closure glaucoma, and four patients with aphakia with ruptured anterior hyaloid face. Main outcome measures included visual acuity and intraocular pressure at 1 year postoperatively. RESULTS At 1 year postoperatively, 31 (77.5%) of 40 patients had stable or improved visual acuity; three eyes (7. 5%) had a final visual acuity of no light perception and three additional eyes (7.5%) were enucleated (because of chronic pain in two eyes and endophthalmitis in one eye). Mean preoperative intraocular pressure was 34 mm Hg and the median number of preoperative antiglaucoma medications was two. At 1 year postoperatively, mean intraocular pressure was 13 mm Hg and the median number of antiglaucoma medications was zero. Twenty-two patients (55.0%) achieved an intraocular pressure greater than 5 mm Hg and less than or equal to 21 mm Hg without antiglaucoma medication, and an additional seven patients (17.5%) achieved this level of intraocular pressure control with medication. Only one patient (2.5%) underwent further glaucoma surgery for uncontrolled intraocular pressure. CONCLUSIONS Although combined pars plana vitrectomy and placement of a glaucoma drainage implant is often a successful management option in selected patients with refractory glaucoma, visual outcome may be poor because of severe underlying ocular disease and postoperative complications.


American Journal of Ophthalmology | 2000

Corneal biopsy in the management of progressive microbial keratitis

George Alexandrakis; Robert Haimovici; Darlene Miller; Eduardo C. Alfonso

PURPOSE To study the indications and role of diagnostic corneal biopsy in the management of patients with progressive microbial keratitis. METHODS The records of 33 consecutive patients who underwent a diagnostic corneal biopsy from January 1, 1986, to December 31, 1998, were reviewed. The indication for corneal biopsy was progressive infectious keratitis despite intensive broad-spectrum topical antimicrobial therapy, or progressive stromal infiltration inaccessible to corneal scrapings. Microbiologic evaluation of all corneal biopsies was performed, and 11 of the 33 biopsies were also examined histopathologically. RESULTS A microorganism was isolated from 27 (82%) of the 33 corneal biopsies. Of the six patients with a negative biopsy, a penetrating keratoplasty was performed in five patients and the pathogen was identified by examination of the corneal button. In one patient no microorganism was identified; however, the infection resolved with topical antimicrobial therapy. The most common risk factor for keratitis was foreign body exposure or corneal abrasion (14 patients). A solid stromal infiltrate was the most common pattern of corneal involvement. Corneal biopsy revealed previously unidentified microorganisms that led to a change in antimicrobial therapy in 24 (89%) of the 27 patients and confirmed prior culture results in the remaining 3 patients. Microbiologic evaluation of the corneal biopsy was more sensitive than histopathologic examination. Acanthamoeba was the most commonly isolated pathogen (five cases), followed by Propionibacterium acnes and Fusarium (four cases each). Gram-positive organisms were isolated in 16 patients. Only five of the 27 patients with a positive corneal biopsy required a penetrating keratoplasty, in contrast to five of the six patients with a negative corneal biopsy (P =.005). During the 13-year period of the study, only three corneal biopsies were performed in the last 6 years. CONCLUSIONS Microbiologic evaluation of a diagnostic corneal biopsy contributed significantly to the diagnosis, treatment, and outcome of patients with progressive infectious keratitis.


Ophthalmology | 2000

Nasolacrimal duct obstruction secondary to ectopic teeth.

George Alexandrakis; Richard N. Hubbell; Phil A. Aitken

OBJECTIVE To describe two patients with nasolacrimal duct obstruction (NLDO) caused by ectopic eruption of teeth. The literature concerning nasal and other unusual ectopic sites of tooth eruption is reviewed. DESIGN Two interventional case reports and literature review. PARTICIPANTS A 3-year-old girl with epiphora and recurrent dacryocystitis of the right eye. Previous medical and surgical management was unsuccessful. A 32-year-old female with a long history of right eye discomfort and epiphora. Previous examinations and workup were negative. INTERVENTION A computed tomographic (CT) scan of the orbits and sinuses was performed in both patients. The ectopic teeth were surgically removed. MAIN OUTCOME MEASURES Nasolacrimal system function and response to treatment at the last follow-up were recorded. RESULTS In the first patient, CT imaging disclosed two teeth within the right inferior meatus compressing the nasolacrimal duct. In the second patient, CT revealed a large dental structure in the maxillary sinus compressing the nasolacrimal duct. Endoscopic tooth extraction and nasolacrimal duct probing in the first patient and surgical removal of the dental structure in the second patient effected complete resolution of symptoms. Both patients were symptom free at last follow-up. CONCLUSIONS These cases suggest that ectopic eruption of teeth should be added to the differential diagnosis of NLDO. Surgical removal of the ectopic teeth compressing the nasolacrimal duct results in resolution of the lacrimal drainage obstruction.


American Journal of Ophthalmology | 2009

Pathogenesis and outcome of Paecilomyces keratitis.

Xiaoyong Yuan; Kirk R. Wilhelmus; Alice Y. Matoba; George Alexandrakis; Darlene Miller; Andrew J.W. Huang

PURPOSE To examine the clinical pathology and management of Paecilomyces lilacinus keratitis. DESIGN Observational case series, literature review, and laboratory study. METHODS Characteristics and outcome of 17 patients with laboratory-confirmed Paecilomyces keratitis treated at 2 referral centers were combined with 25 previously reported cases. Experimental models were developed by topically inoculating a human corneal isolate of P. lilacinus onto murine eyes and onto human donor corneas. RESULTS Of 42 reported eyes with Paecilomyces keratitis, 13 (31%) were associated with chronic keratopathy or previous ocular surgery, 11 (26%) followed corneal trauma, and 10 (24%) occurred in soft contact lens wearers. Medical cure occurred in 13 (31%), including 9 of 31 eyes (29%) treated with natamycin or amphotericin B. Penetrating keratoplasty or other surgery was performed in 29 (69%). In vitro testing of P. lilacinus indicated resistance to natamycin and amphotericin B but susceptibility to ketoconazole and voriconazole. Experimental inoculation after superficial scarification established moderately severe corneal paecilomycosis by hyphae and conidia in immunosuppressed mice and in explanted donor corneas. CONCLUSIONS P. lilacinus is an emerging fungal pathogen that infects corneal tissue by filamentous invasion with occasional intrastromal sporulation. P. lilacinus keratitis does not reliably respond to natamycin or amphotericin B and has often required therapeutic keratoplasty, but topical azole antifungal agents such as voriconazole appear promising.


American Journal of Ophthalmology | 2000

Recurrent orbital solitary fibrous tumor in a 14-year-old girl

George Alexandrakis; Thomas E. Johnson

PURPOSE To report a case of orbital solitary fibrous tumor in a pediatric patient. METHODS Case report and review of the literature. RESULTS A 14-year-old girl presented with a 5-month history of painless proptosis of the left eye. Magnetic resonance imaging revealed a well-circumscribed mass in the anterior superomedial left orbit. The lesion was excised, and histopathologic examination revealed a solitary fibrous tumor. The lesion recurred in the orbit 4 months postoperatively, and histologic examination of the new lesion was consistent with solitary fibrous tumor. CONCLUSION Based on this case report of orbital solitary fibrous tumor in a pediatric patient, solitary fibrous tumor should be included in the differential diagnosis of pediatric orbital tumors.


Ophthalmology | 2000

Visual acuity outcomes with and without surgery in patients with persistent fetal vasculature.

George Alexandrakis; Ingrid U. Scott; Harry W. Flynn; Timothy G. Murray; William J. Feuer

PURPOSE To investigate visual acuity outcomes in patients with persistent fetal vasculature (PFV) left untreated or treated with vitreoretinal surgical techniques and to investigate clinical features associated with prognosis. DESIGN Retrospective, noncomparative case series. PARTICIPANTS All patients with PFV examined at the Bascom Palmer Eye Institute from January 1, 1983 through December 31, 1998. INTERVENTION All patients in the study had unilateral PFV. Of 42 PFV patients identified, 30 patients underwent vitreoretinal surgery. Indications for surgery included media opacity (e.g., cataract), vitreoretinal traction, and retinal detachment. MAIN OUTCOME MEASURES Final best postoperative visual acuity, prognostic ocular clinical features, and surgical complications. RESULTS In the surgical group of patients, median age at diagnosis was 8 weeks, and median length of follow-up was 32 months, with all patients having at least 1 year of follow-up. Two patients had clinical and echographic findings consistent with anterior PFV, 2 patients had strictly posterior PFV, and the remaining 26 patients had components of both anterior and posterior PFV. Fourteen eyes (47%) achieved a final visual acuity of 20/400 or better at last follow-up. Risk factors for a poor visual acuity outcome (<20/400) included microphthalmia (28% of patients with microphthalmia versus 67% of patients with normal axial length achieved a final vision of 20/400 or better; P = 0.061) and preoperative retinal detachment or retinal or optic nerve abnormalities, or both, such as hypoplasia, folds, or indistinct macula with hypopigmentation (25% of patients with any of these anomalies versus 61 % of patients without these findings achieved a final vision of 20/400 or better; P = 0.072). After surgery, retinal detachment developed in three eyes, chronic hypotony in two other eyes, and neovascular glaucoma in one eye. In the nonsurgical group there were 6 male and 6 female patients. Two patients with posterior PFV had minimal disease and were not considered surgical candidates, whereas 10 patients with combined anterior and posterior PFV had advanced pathologic features, and it was believed that surgery would not offer significant visual improvement; median age at diagnosis was 9.5 months, and median length of follow-up was 36 months, with all patients having at least 1 year of follow-up. At last follow-up, 3 eyes (25%) had a final visual acuity of 20/400 or better. During follow-up, retinal detachment developed in 2 eyes and chronic hypotony in an additional 2 eyes. CONCLUSIONS The current study indicates that approximately 50% of patients undergoing surgery for PFV will achieve useful vision. Visual acuity outcomes in patients with PFV are correlated with the nature and extent of ocular risk factors. Some patients may not be candidates for surgery because of either minimal changes or advanced disease that limit the potential of visual improvement.


American Journal of Ophthalmology | 1999

Purtscher-like retinopathy associated with pancreatic adenocarcinoma.

Homayoun Tabandeh; Philip J. Rosenfeld; George Alexandrakis; Jan P Kronish; Nauman A Chaudhry

PURPOSE To investigate a case of Purtscher-like retinopathy that occurred in association with pancreatic adenocarcinoma. METHOD Case report. RESULTS A 63-year-old woman presented with multiple gray patches in the central vision of both eyes. Visual acuity was 20/20 in both eyes. Funduscopy showed large peripapillary yellow-white patches within the superficial retina and small superficial retinal hemorrhages in both eyes. The patient subsequently had abdominal pain. Computed tomography of the abdomen demonstrated a large pancreatic mass with extension into the liver. Histologic examination of a percutaneous needle biopsy specimen showed mucinous pancreatic adenocarcinoma. CONCLUSION Pancreatic adenocarcinoma should be added to the list of systemic diseases that can be associated with Purtscher-like retinopathy.


Ophthalmic Surgery and Lasers | 1999

Combined Cataract Surgery, Intraocular Lens Insertion, and Vitrectomy in Eyes with Idiopathic Epiretinal Membrane

George Alexandrakis; Nauman A Chaudhry; Harry W. Flynn; Timothy G. Murray

To report the surgical outcomes of combined cataract surgery and pars plana vitrectomy in eyes with idiopathic epiretinal membrane. This is a retrospective review of 8 consecutive patients with concurrent cataract and idiopathic epiretinal membrane who underwent the combined procedure. At a mean follow-up of 22 months, the visual acuity improved by 2 or more Snellen lines in 7 patients (88%). Median preoperative and postoperative best-corrected visual acquities were 20/200 and 20/50 respectively. Simultaneous cataract surgery and vitrectomy for idiopathic epiretinal membrane removal resulted in visual improvement in the majority of patients.


Ophthalmic Surgery and Lasers | 2000

Intracranial penetrating orbital injury

George Alexandrakis; Janet L. Davis

The authors report a case of double-penetrating injury of the globe with intracranial involvement from a pellet gun. A 16-year-old boy had a visual acuity of bare light perception in the left eye after being hit by a pellet. There was an inferior limbal entry site, dense hyphema, and no view of the fundus. Computed tomographic scan showed the pellet intracranially close to the left cavernous sinus. After neurosurgical clearance, the patient underwent primary closure of the corneoscleral entry site followed 3 weeks later by pars plana vitrectomy, lensectomy, and repair of a rhegmatogenous retinal detachment. At 12 months postoperatively, visual acuity was 20/300 and the retina was attached. Our case demonstrates the potential for significant visual recovery in some patients with a penetrating orbital injury and intracranial involvement. Complete radiographic evaluation with neurosurgical consultation is important in the management of these patients prior to ophthalmologic intervention with possible foreign body removal. There is a need for more public awareness regarding the potentially harmful effects of pellet guns.

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Ingrid U. Scott

Pennsylvania State University

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Andrew J.W. Huang

Washington University in St. Louis

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