Alejandro Tello

Dr. Alejandro Tello


Research Focus & Metrics

Academic Career Length

20Years (2007-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 May 2015 in Eye
Verified
Journal Article
Closed access
ATAlejandro Tello
Alejandro Tello
TSTrevor Sherwin
Trevor Sherwin
ATAlejandro Tello
Alejandro Tello
JMJ Merayo
J Merayo
RBR Barrera
R Barrera
AAA Acera
A Acera

28 October 2019 in Graefe's Archive for Clinical and Experimental Ophthalmology
Verified
Journal Article
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ATAlejandro Tello
Alejandro Tello
JVJohn F. Villamil
John F. Villamil
MAMaría Fernanda Acuña
María Fernanda Acuña
PLPaul A Camacho Lopez
Paul A Camacho Lopez
JMJesús Merayo-Lloves
Jesús Merayo-Lloves
APAngélica María Prada
Angélica María Prada

1 December 2007 in Cornea
Verified
Journal Article
Closed access
ATAlejandro Tello
Alejandro Tello
ATAlejandro Tello
Alejandro Tello
JDJulián Delgado
Julián Delgado
FVFabián Valencia
Fabián Valencia
AGAugusto J Gómez
Augusto J Gómez
Luis DiazLuis Diaz
Luis Diaz
To report a case of late bacterial keratitis after intrastromal corneal ring segments (ICRSs; Ferrara ring; Ferrara Ophthalmics, Belo Horizonte, Brazil). Review the clinical findings in a 42-year-old woman with bilateral keratoconus who underwent implantation of Ferrara ring segments in her left eye and 4 months later presented with corneal infiltrates and hypopyon. Bacterial staining, culture, and antibiotic sensitivities were done. Medical treatment and rings explantation were performed. The cultures revealed growth of vancomycin-oxacillin sensible coagulase-positive Staphylococcus aureus. Treatment with topical moxifloxacin, topical imipenem, and systemic intravenous and topical vancomycin was kept for two weeks. Corneal inflammation and hypopyon resolved, leaving a minimal residual leucoma. Infectious keratitis is an uncommon complication of ICRS and it may be late in presentation, even months after implantation. Importance of patient education about alarm symptoms and the need for long-term close postoperative follow-up cannot be underestimated. If a change in surgical technique, i.e., suturing the incision, has an influence in this complication's incidence, it will require further studies.

9 February 2024 in Cornea
Verified
Journal Article
Open access
APAngelica M. Prada
Angelica M. Prada
FQFernando Beng Quintero
Fernando Beng Quintero
KMKevin Beng Mendoza
Kevin Beng Mendoza
ATAlejandro Tello
Alejandro Tello
ATAlejandro Tello
Alejandro Tello
Andres G. MarrugoAndres G. Marrugo
Andres G. Marrugo
Purpose: The aim of this study was to evaluate the efficacy of artificial intelligence–derived morphometric parameters in characterizing Fuchs corneal endothelial dystrophy (FECD) from specular microscopy images. Methods: This cross-sectional study recruited patients diagnosed with FECD, who underwent ophthalmologic evaluations, including slit-lamp examinations and corneal endothelial assessments using specular microscopy. The modified Krachmer grading scale was used for clinical FECD classification. The images were processed using a convolutional neural network for segmentation and morphometric parameter estimation, including effective endothelial cell density, guttae area ratio, coefficient of variation of size, and hexagonality. A mixed-effects model was used to assess relationships between the FECD clinical classification and measured parameters. Results: Of 52 patients (104 eyes) recruited, 76 eyes were analyzed because of the exclusion of 26 eyes for poor quality retroillumination photographs. The study revealed significant discrepancies between artificial intelligence–based and built-in microscope software cell density measurements (1322 ± 489 cells/mm2 vs. 2216 ± 509 cells/mm2, P < 0.001). In the central region, guttae area ratio showed the strongest correlation with modified Krachmer grades (0.60, P < 0.001). In peripheral areas, only guttae area ratio in the inferior region exhibited a marginally significant positive correlation (0.29, P < 0.05). Conclusions: This study confirms the utility of CNNs for precise FECD evaluation through specular microscopy. Guttae area ratio emerges as a compelling morphometric parameter aligning closely with modified Krachmer clinical grading. These findings set the stage for future large-scale studies, with potential applications in the assessment of irreversible corneal edema risk after phacoemulsification in FECD patients, as well as in monitoring novel FECD therapies.

1 December 2011 in Revista de Salud Pública
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ATAlejandro Tello
Alejandro Tello
ATAlejandro Tello
Alejandro Tello
LÁLeonardo Álvarez-Osorio
Leonardo Álvarez-Osorio
JRJuan J. Rey-Serrano
Juan J. Rey-Serrano
Determining Demodex folliculorum infection prevalence in patients attending general ophthalmological consultation and such infection's association with blepharitis. This was a descriptive study of such prevalence. 128 subjects who attended the Virgilio Galvis Eye Centre were randomly selected and the presence of D. folliculorum was determined in 4 eyelashes taken from each of them. D. folliculorum infection prevalence was 42.1% (n=54); blepharitis was diagnosed in 38.3% of the patients (n=49) and 63.2% of them (n=31) were positive for D. folliculorum. Only 29.2% of the individuals in the group without blepharitis (n=79) had mites (n=23) (p=0.0003). A higher number of parasites was found in patients with blepharitis (12.7 parasitic load index cf 5.1; p=0.0001); 25% (n=32) of the participants had scaling in the form of cylinders and 96.9% of these had the mites (n=31), whereas the mite was only present in 24% (n=23) of subjects who had no cylinder-type scaling (n=96). Demodex folliculorum is a parasite found in people without ocular lesions; however, it is more frequent and has a higher parasite burden in patients with blepharitis. Our results suggested the need for investigating the presence of D. folliculorum in all patients suffering from blepharitis, especially in cases where cylinder-type scaling has been observed in their eyelashes.

1 April 2014
Verified
Journal Article
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ATAlejandro Tello
Alejandro Tello
ATAlejandro Tello
Alejandro Tello
AGAlfredo Guerra
Alfredo Guerra
MAMaría Fernanda Acuña
María Fernanda Acuña
DVDonaldo Villarreal
Donaldo Villarreal
Bacterial resistance is critical for the selection of antibiotics in the treatment of infections, so it is vital to know its current status in our geographical area. To determine in vitro antibiotic susceptibility of bacterial isolates obtained from keratitis and intraocular infections. A retrospective study of microbiological tests in Fundación Oftalmológica de Santander (FOSCAL) was carried out between June, 2011, and January, 2012. A total of 92 samples were examined and 110 bacteria, 27 fungi and 12 free-living amoebae were identified. Polymicrobial infections constituted 50% of the total; 1.1%, 0%, 1.1%, 16.9%, 29.3% and 85% of Gram-positive bacteria were resistant to imipenem, moxifloxacin, gatifloxacin, levofloxacin, ciprofloxacin and tobramycin, respectively, while 0%, 8.3%, 0%, 0%, 18.2% and 27.3% of Gram-negative bacteria were resistant to imipenem, moxifloxacin, gatifloxacin, levofloxacin, ciprofloxacin and tobramycin, respectively. For methicillin-resistant coagulase-positive staphylococci, resistance percentages to imipenem, moxifloxacin, gatifloxacin, levofloxacin, ciprofloxacin and tobramycin were 0%, 0%, 0%, 7%, 17% and 100%, respectively. For methicillin-resistant coagulase-negative staphylococci, resistance percentages to imipenem, moxifloxacin, gatifloxacin, levofloxacin, ciprofloxacin and tobramycin were 3%, 0%, 0%, 24%, 44% and 100%, respectively. Overall bacterial resistance to imipenem, moxifloxacin, gatifloxacin, levofloxacin, ciprofloxacin and tobramycin, for both Gram-positive and Gram-negative, was 1%, 1%, 1%, 15.1%, 28% and 64.5%, respectively. The levels of bacterial resistance to imipenem, moxifloxacin and gatifloxacin were lower than for levofloxacin, ciprofloxacin and tobramycin. The levels of resistance to tobramycin were very high, which calls into question its usefulness in this region of our country.