Biomedical subjects

V Lorencová

Publications and source records attributed to V Lorencová.

10 recordsLinked to original sources

PubMed2006

[Correction of the astigmatism with the Artisan phakic toric lens].

The implantation of the intraocular anterior chamber phakic toric lens (PTIOL) Artisan, a product of the Ophtec company, is one of the most up-to-date methods of the correction of higher degree of myopic as well as hyperopic astigmatism. The authors refer about the results of PTIOL Artisan implantation in 6 patients (10 eyes). The major indication was the hyperopic astigmatism--in 5 patients (8 eyes); in one patient the indication was myopic astigmatism. In the followed up group of patients, there is the preponderance of men (5), and one woman only. The patients were divided into two subgroups: one with myopic astigmatism (1 patient, 2 eyes) and other with hyperopic astigmatism (5 patients, 8 eyes). The average age of the whole group at the time of the surgery was 27.7 +/- 2.8 years (range 23-38 years) and the average follow up period was 13.0 +/- 6.9 months (range 6-22 months). In the group the patients with follow up period shorter than 6 months were not included. The average preoperative spherical refractive error was +4.8 +/- 2.25 dioptres (D) and the average astigmatic error was -5.15 +/- 2.82 cylinders (Dcyl). In one case of myopia, the preoperative refractive error in both eyes was -7.0 D and -3.5 Dcyl. The target refraction was emetropia +/- 1.0 D. The authors evaluate the final uncorrected and best-corrected visual acuity (UCVA, BCVA), final postoperative refractive error, presence of intra- as well as postoperative complications, and changes of endothelial cells' density over time. The average final postoperative error in patients with hyperopic astigmatism was +0.72 +/- 0.93 D and -1.08 +/- 0.60 Dcyl. In the only patient with myopic astigmatism the final postoperative error of both eyes was +0.5 D and -0.5 Dcyl. The advantage of the PTIOL implantation is fast visual recovery, potential reversibility of the procedure, maintaining of the accommodation, and stability of the postoperative refraction.

Adult↗

PubMed2006

[The use of accommodative lenses for surgical correction of the presbyopia using the Prelex method].

The authors refer about their experience with the surgical correction of the presbyopia by means of the Prelex (presbyopic lens exchange) method. Patients, who underwent this type of refractive surgery procedure to decrease their dependency on glasses correction for far as well as for near vision (12 patients, 23 eyes) and 1 young female patient (2 eyes) with juvenile cataract and high hyperopia, were included in the study. The average age at the time of the surgery was 51.0 +/- 5.5 years (range, 19-77 years). The average follow up period of the whole group of patients is 9.8 months (range, 1-13 months). Depending on the type of the lens implanted, the group was divided into subgroup A with the accommodative lens 1 CU produced by Human Optics Company implanted, and subgroup B with the accommodative lens Kellan TetraFlex KH 3500 produced by LensTec Company implanted. The subgroup A consists of 8 patients (15 eyes) with the average preoperative refractive error +2.35 +/- 3.45 diopters. The average uncorrected visual acuity of this group was 0.24 +/- 0.18, and the average best-corrected visual acuity was 0.77 +/- 0.22 at the time before the surgery. The average glasses correction for near was +4.1 dioptres, and the uncorrected vision for near was Jaeger's table Nr. (J) 13. The B subgroup consists of 5 patients (10 eyes). The average preoperative refractive error was +2.23 +/- 0.93 diopters. The average value of the uncorrected visual acuity before the surgery was 0.43 +/- 0.28, and the average corrected visual acuity was 0.82 +/- 0.25. The average value of the glasses correction for near was +5.25 and uncorrected vision for near J 13. The final average postoperative error at the time of the last visit was in the A subgroup +0.06 +/- 1.17 dioptres. The average uncorrected visual acuity was 0.69 +/- 0.24, and the average best-corrected visual acuity 0.96 +/- 0.12. The average vision of the patients of this subgroup for near was J 3. In the B subgroup we found at the last visit the average final value of the postoperative refractive error -0.2 +/- 0.72 dioptres. The average uncorrected visual acuity 0.57 +/- 0.22 and the average corrected visual acuity 0.95 +/- 0.12. Average uncorrected vision for near was J 5. We did not notice any serious per- or postoperative complication of this procedure.

Accommodation, Ocular↗

PubMed2004

[Implantation of multifocal intraocular lenses].

The authors refer to the first experience in implantation of multifocal intraocular lens (MIOL) AMO ARRAY (model SA 40 N) produced by Allergan to a group of 35 patients (69 eyes). The proportion of men in the group was 42.9%, women being 57.1%. The mean age of the group was 50.9 +/- 4.3 year, range 36-71 years. The implantation of this type of intraocular lens was made due to a refractory intervention on a clear lens in 84.0% eyes and operation on cataract in 16.0%. The study was aimed at evaluation of the results of visual acuity for short and long distances, resulting refraction after the operation, the occurrence of side visual phenomena and their tolerance by the patient, necessary supplementary eyeglass correction especially in patients after refraction lensectomy. Uncorrected visual acuity for long distances 0.7 or better was in 75.9% of patients. Sixty one % of patients with MIOL in both eyes do not require glasses for vision into short distances (No 1-3).

Adult↗

PubMed2004

[Photorefractive keratectomy in hypermetropia].

AIM: To evaluate the results in patients with hypermetropia having undergone photoreactive keratectomy (PRK). GROUP AND METHODS: The authors present a retrospective analysis of the results in 40 eyes operated on PRK in the period of September 1997 to November 2002 at the Eye Clinic of the Faculty Hospital in Hradec Králové. The mean preoperation spherical refraction was 2.90 +/- 0.98 dioptry (D), the mean astigmatism being -0.82 +/- 0.78 D, visual uncorrected visual acuity (NZO) 0.37 +/- 0.37, the mean corrected visual acuity (KZO) 1.28 +/- 0.27). RESULTS: One year after the operation on 31 eyes, the resulting mean spherical refraction was 0.76 +/- 1.10 D, the mean astigmatism being -1.01 +/- 0.80 D, NZO 0.77 +/- 0.18, KZO 0.99 +/- 0.21, NZO 6/12 and better was detected in 94% of surgically treated eyes. CONCLUSION: The PRK method has been found sufficiently effective for the correction of low and medium hypermetropia.

Female↗

PubMed2004

[Effect of adjustment of corneal running sutures on cylindrical refraction after perforating keratoplasty].

Authors refer about the effect of adjusting (adjustment of the suture tension) of the running corneal suture on the final cylindrical refraction in patients who underwent penetrating keratoplasty due to keratoconus. In our article we evaluate two groups of patients. The group I consists 76 patients (76 eyes) who regularly visited our department of ophthalmology. There were 52.6% of females and 47.4% of males. The average age at the time of surgery was 33.5 +/- 5.2 years (range, 18-52 years). In this group of patients, the adjusting was performed during the surgery. In the group II 35 patients (40 eyes) underwent the adjusting procedure of the running corneal suture in the early postoperative period. There were 19 (54.0%) women and 16 (46.0%) men. The average age of the whole group at the time of surgery was 34.6 +/- 3.8 years (range, 18-50 years). The indication to carry out the adjusting was topographically verified astigmatism of more then 3.5 cylindrical diopters (D cyl). The purpose of this study was to find the ultimate surgery technique to get not only the clearness and good healing of the corneal graft, but first of all to prevent extensive ametropia already during the surgery. In the early stage after the surgery we are trying to reduce emerged refractive error and to get faster recovery of good visual acuity of the operated eye. In the sense of the least final postoperative astigmatism, the best results we have reached in cases where the donor corneal graft was 0.25 mm larger in diameter and the suture was adjusted during the surgery using light circles according to Serdarevic. In this group of patients the average final cylindrical refractive error after the surgery was 2.00 +/- 0.81 D cyl. When adjusting the corneal suture in postoperative period, the mean final refractive error decreased of about 3.09 +/- 1.62 D cyl.

Adolescent↗

PubMed2003

[Corneal surface analysis].

Fourier analysis is a powerful method of evaluating the surface of the cornea. In 50 patients after photorefractive keratectomy included in our study we measured spherical equivalent, regular astigmatism, irregular astigmatism and decentration retrospectively acquired by Fourier series analysis of corneal topography data 1, 3, 6 and 12 months after operation. Postoperative decentration increased significantly from a mean preoperative value. The preoperative and postoperative values are not significantly different. The Fourier spherical equivalent and the values of keratometric spherical (equivalent) are highly correlated. Correlation among decentration, irregular astigmatism and best corrected visual acuity is important for clinical practice. Due to Fourier analysis we obtain information, which could explain worse results of some surgeries.

Astigmatism↗

PubMed2003

[Refractive surgery in myopia up to -6D].

OBJECTIVE: To evaluate the clinical results in patients with myopia up to -6 dioptres (D) after refraction surgery, evaluate their stability and compare photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK). MATERIAL AND METHODS: The authors evaluated before and after surgery the refraction values in patients with myopia up to -6 D operated in 1999 and 2000. The patients were subjected to standard examination before operation, one week, 1, 3, 6 and 12 months after operation. The group comprised a total of 542 eyes, 452 PRK eyes and 90 LASIK eyes. RESULTS: After PRK surgery the mean spherical refraction after one year was -0.35 +/- 0.71 D, the mean astigmatism -0.63 +/- 0.38 D, UCVA 0.90 +/- 0.19, BCVA 0.98 +/- 0.11. After LASIK surgery after one year the mean spherical refraction was -0.10 +/- 0.81. D, the mean astigmatism -1.05 +/- 0.65 D, UCVA 0.80 +/- 0.24, BCVA 0.86 +/- 0.21. CONCLUSION: Both methods proved effective and safe for correction of myopia up to -6 D. The results at our clinic are comparable with other departments and are stable in different years. PRK and LASIK achieve equal postoperative results after an interval of 3 to 6 months following surgery.

Astigmatism↗

PubMed2003

[Long-term results of photorefractive keratectomy in myopia up to -6 D].

OBJECTIVE: To present clinical results of patients with myopia up to -6 dioptres (D) after photorefractive keratectomy (PRK) and evaluate their stability during a 4-year period. MATERIAL AND METHODS: The authors evaluated retrospectively the refraction before and after surgery in patients with myopia up to -6 D during the period from September 1997 till December 2000. The group comprised a total of 847 eyes. The mean spherical refraction during the whole follow up period was before surgery -3.61 +/- 1.17 D, the mean astigmatism was -0.65 +/- 0.63 D, non-corrected visual acuity (UCVA) 0.09 +/- 0.09, the visual acuity with optimal correction (BCVA) 1.21 +/- 0.30. RESULTS: One year after PRK we achieved in our group a mean spherical refraction of -0.17 +/- 0.74 D, a mean astigmatism of -0.61 +/- 0.43 D, UCVA 0.92 +/- 0.25, BCVA 1.02 +/- 0.19. CONCLUSION: Photorefractive keratectomy is an effective and safe method for correction of myopia up to -6 D. The results as regards refraction were comparable with other departments and did not differ much during individual years. Stabilization occurs 3-6 months after the operation.

Follow-Up Studies↗

PubMed2003

[Stability of corneal optic power after photorefractive keratectomy].

Changes in the values of optical power of cornea in patients after photorefractive keratectomy (PRK) obtained by Fourier analysis of videotopographic picture of cornea were investigated. The authors compared changes of cornea surface (optical power) in patients with preoperation myopia up to 6 and more than 6 diopters. Moreover, the changes of absolute values of corneal optical power were compared with the development of refraction of the optical system as a whole. In patients with a lower degree of myopia the cornea optical power became stable up to 6 months after the operation. The cornea surface in patients with higher myopia was still changing one year after the operation. The changes of optical power of cornea in patients with a higher myopia were more marked, but the differences were not statistically significant (except for the period after cornea ablation). There was not any significant difference between the changes of objective refraction and the changes of cornea optical power. The main cause of fluctuating postoperative refraction is apparently the change of cornea surface associated with healing of cornea.

Adult↗

PubMed2001

[PRK and LASIK in patients with myopia ranging from -6 to -9 D] ].

OBJECTIVE: Observing of effectiveness, safety and short-term stability of patients with myopia ranging from -6.0 to -9.0 diopters (D) after surgery and their comparison. PARTICIPANTS AND METHOD: We were retrospectively analyzing pre- and postoperative outcomes of patients with myopia ranging from -6.0 to -9.0 D. 90 eyes were examined before laser in situ keratomileusis (LASIK) with mean spherical equivalent refraction -7.64 +/- 0.84 D and mean cylinder -1.23 +/- 1.1 D. 56 eyes were examined before photorefractive keratectomy (PRK) with mean spherical equivalent refraction -6.92 +/- 0.72 D and mean cylinder -0.60 +/- 0.55 D. Patients were examined before operation, one week, one month, three months, six months, nine months and one year after operation. Data were collected and analyzed by the computer programme. RESULTS: We observed the patients who underwent the operation and six months after surgery we received following results: After PRK mean spherical equivalent refraction was -0.23 +/- 1.24 D, mean cylinder -0.83 +/- 0.42 D, uncorrected visual acuity (UCVA) 0.86 +/- 0.35, best spectacle-corrected visual acuity (BCVA) 1.13 +/- 0.33. After LASIK mean spherical equivalent refraction was -0.29 +/- 1.19 D, mean cylinder -1.14 +/- 0.77 D, UCVA 0.65 +/- 0.25, BCVA 0.83 +/- 0.25. One year after PRK mean spherical equivalent refraction was -0.44 +/- 1.26 D, mean cylinder -0.80 +/- 0.57 D, UCVA 0.81 +/- 0.31, BCVA 0.97 +/- 0.21. After LASIK mean spherical equivalent refraction was -0.14 +/- 0.86 D, mean cylinder -1.26 +/- 0.89 D, UCVA 0.75 +/- 0.25, BCVA 0.89 +/- 0.20. CONCLUSIONS: Both methods are effective and their results after 3 to 6 months after laser treatment in patients with myopia ranging from -6.0 to -9.0 D were comparable. Based on the complex evaluation, we prefer LASIK nowadays.

Adult↗