Alexander Shpak

Prof. Dr. Alexander Shpak

orcid

Research Focus & Metrics

Academic Career Length

32Years (1995-Present)

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

Representative Publications

View All Publications
1 December 2010 in Epilepsy Research
Verified
Journal Article
Closed access
AGAlla Guekht
Alla Guekht
WHW. Allen Hauser
W. Allen Hauser
LMLarissa Milchakova
Larissa Milchakova
YCYury Churillin
Yury Churillin
ASAlexander Shpak
Alexander Shpak
EGEugene Gusev
Eugene Gusev

9 November 2017 in Current Eye Research
Verified
Journal Article
Closed access
ASAlexander Shpak
Alexander Shpak
AGAlla B Guekht
Alla B Guekht
TDTatiana A Druzhkova
Tatiana A Druzhkova
KKKsenia I Kozlova
Ksenia I Kozlova
NGNatalia V Gulyaeva
Natalia V Gulyaeva
To study brain-derived neurotrophic factor (BDNF) content in aqueous humor (AH), lacrimal fluid (LF), and blood serum (BS) in patients with age-related cataract and primary open-angle glaucoma (POAG). BDNF was studied in 57 patients with age-related cataract, 55 patients with POAG combined with cataract, and 29 healthy controls (one eye in each person). AH was sampled during cataract surgery. The levels of BDNF in LF and BS did not differ in cataract patients and controls. The concentration of BDNF (pg/mL) in patients with POAG and cataract was lower than in cataract patients in AH (35.2 ± 14.2 vs. 54.6 ± 29.6, P < 0.001), LF (78.0 ± 25.1 vs. 116.2 ± 43.1, P < 0.001), and BS (19230 ± 5960 vs. 22440 ± 7580, P < 0.02), while the AH/LF ratio was similar (0.46 ± 0.18 vs. 0.48 ± 0.19). The AH level of BDNF declined in early POAG and relatively increased in the next stages of the disease, inversely correlating with visual field index (Pearson's correlation coefficient r = -0.404, P = 0.002) and average retinal nerve fiber layer thickness (r = -0.322, P = 0.018). BDNF contents in LF and BS were also the lowest in early POAG. BDNF in AH strongly correlated with its content in LF (r = 0.66, P < 0.000). A formula was suggested to calculate the AH concentration of BDNF basing on its content in LF. BDNF contents are decreased in AH, LF, and BS of patients with POAG demonstrating a significant decrease in the early POAG and relative increase in the next stages of the disease. A strong correlation exists between BDNF contents in AH and LF.

1 August 2012 in Journal of Cataract & Refractive Surgery
Verified
Journal Article
Closed access
Boris E. MalyuginBoris E. Malyugin
Boris E. Malyugin
ASAlexander Shpak
Alexander Shpak
DPDmitry F. Pokrovskiy
Dmitry F. Pokrovskiy
To study the accommodative changes in the central anterior chamber depth (ACD) in patients with high myopia using anterior segment optical coherence tomography (AS-OCT). Cataract Surgery Department and Clinical & Functional Diagnostics Department, S. Fyodorov Eye Microsurgery Complex-Federal State Institution, Moscow, Russian Federation. Prospective case-control study. The ACD measurements were obtained in the nonaccommodative state (baseline) and during accommodation using the Visante AS-OCT device. Thirty-six myopic eyes (36 patients; mean age 27 years; mean spherical equivalent (SE) -12.52 diopters [D]) and 31 emmetropic eyes (31 subjects; mean age 26 years; mean SE -0.39 D) were examined. At baseline, the mean ACD in both groups was similar. During accommodation, the mean maximum changes in the ACD were significantly less pronounced in the myopia group (-0.14 mm ± 0.07 [SD]; range -0.03 to -0.29 mm) than in the emmetropia group (-0.22 ± 0.08 mm; range -0.04 to -0.35 mm) (P<.0001). Ten patients in the myopia group had a critically shallow anterior chamber (ACD <2.8 mm) in the state of accommodation. Accommodative changes in the ACD were significantly less pronounced in eyes with high myopia than in emmetropic eyes. Still, the anterior chamber might become critically shallow during accommodation in some myopic eyes, and this should be taken into account when planning phakic intraocular lens implantation to correct high myopia. No author has a financial or proprietary interest in any material or method mentioned.

1 May 2017 in Epilepsy & Behavior
Verified
Journal Article
Closed access
AGAlla Guekht
Alla Guekht
AGAnna Gersamiya
Anna Gersamiya
IKIgor Kaimovskiy
Igor Kaimovskiy
MMMaria Mizinova
Maria Mizinova
AYAlexander Yakovlev
Alexander Yakovlev
ASAlexander Shpak
Alexander Shpak

1 August 2015 in Journal of Cataract & Refractive Surgery
Verified
Journal Article
Closed access
Boris E. MalyuginBoris E. Malyugin
Boris E. Malyugin
ASAlexander Shpak
Alexander Shpak
DPDmitry F. Pokrovskiy
Dmitry F. Pokrovskiy
To use anterior segment optical coherence tomography (AS-OCT) to evaluate the clinical effectiveness of Implantable Collamer Lens posterior chamber phakic intraocular lens (PC pIOL) sizing based on measurement of the distance from the iris pigment end to the iris pigment end. S. Fyodorov Eye Microsurgery Federal State Institution, Moscow, Russia. Evaluation of diagnostic test or technology. Stage 1 was a prospective study. The sulcus-to-sulcus (STS) distance was measured using ultrasound biomicroscopy (UBM) (Vumax 2), and the distance from iris pigment end to iris pigment end was assessed using a proposed AS-OCT algorithm. Part 2 used retrospective data from patients after implantation of a PC pIOL with the size selected according to AS-OCT (Visante) measurements of the distance from iris pigment end to iris pigment end. The PC pIOL vault was measured by AS-OCT, and adverse events were assessed. Stage 1 comprised 32 eyes of 32 myopic patients (mean age 28.4 years ± 6.3 [SD]; mean spherical equivalent [SE] -13.11 ± 4.28 diopters [D]). Stage 2 comprised 29 eyes of 16 patients (mean age 27.7 ± 4.7 years; mean SE -16.55 ± 3.65 D). The mean STS distance (12.35 ± 0.47 mm) was similar to the mean distance from iris pigment end to iris pigment end distance (examiner 1: 12.36 ± 0.51 mm; examiner 2: 12.37 ± 0.53 mm). The PC pIOL sized using the new AS-OCT algorithm had a mean vault of 0.53 ± 0.18 mm and did not produce adverse events during the 12-month follow-up. In 16 of 29 eyes, the PC pIOL vault was within an optimum interval (0.35 to 0.70 mm). The new measurement algorithm can be effectively used for PC pIOL sizing. No author has a financial or proprietary interest in any material or method mentioned.

28 January 2017 in Epilepsy & Behavior
Verified
Journal Article
Closed access
PDF file
AGAlla Guekht
Alla Guekht
NZNazira нет Zharkinbekova
Nazira нет Zharkinbekova
ASAlexander Shpak
Alexander Shpak
AHAllen Hauser
Allen Hauser