Endothelial cell loss and surgically induced astigmatism after sutureless large-incision manual cataract extraction (SLIMCE).

OBJECTIVES:

To describe a modified manual cataract extraction technique, sutureless large-incision manual cataract extraction (SLIMCE), and to report its clinical outcomes.

METHODS:

Case notes of 50 consecutive patients with cataract surgery performed using the SLIMCE technique were retrospectively reviewed. Clinical outcomes 3 months after surgery were analyzed, including postoperative uncorrected visual acuity, best-corrected visual acuity, intraoperative and postoperative complications, endothelial cell loss, and surgically induced astigmatism using the vector analysis method.

RESULTS:

At the 3-month follow-up, all 50 patients had postoperative best-corrected visual acuity of at least 20/60, and 37 patients (74%) had visual acuity of at least 20/30. Uncorrected visual acuity was at least 20/68 in 28 patients (56%) and was between 20/80 and 20/200 in 22 patients (44%). No significant intraoperative complications were encountered, and sutureless wounds were achieved in all but 2 patients. At the 3-month follow-up, endothelial cell loss was 3.9%, and the mean surgically induced astigmatism was 0.69 diopter.

CONCLUSIONS:

SLIMCE is a safe and effective manual cataract extraction technique with low rates of surgically induced astigmatism and endothelial cell loss. In view of its low cost, SLIMCE may have a potential role in reducing cataract blindness in developing countries.

Fertility of rat epididymal sperm after chemically and surgically induced sympathectomy

Guanethidine, a chemical that selectively blocks sympathetic noradrenergic neurons, was used to investigate the role of sympathetic innervation in the fertility of rat epididymal sperm, using both natural mating and in utero insemination protocols. This animal model correlates, at least in part, with spinal cord injury (SCI) in men. Adult male rats were treated daily by i.p. injections, for 21 or 42 days, with 0 or 6.25 mg/kg guanethidine. To compare the effects of guanethidine-induced sympathectomy with those following surgically induced sympathectomy, the inferior mesenteric ganglion and the proximal hypogastric nerves were removed in another group of rats. Both chemically and surgically induced sympathectomy increased the weight of the epididymis and seminal vesicles/coagulating glands as well as the number and the transit time of cauda epididymal sperm. Neither serum testosterone levels nor LH was affected by treatment with guanethidine. Using natural mating, no litters were produced by guanethidine-treated rats. Chemically denervated rats failed to produce copulatory plugs or ejaculate into the uterus. However, distal cauda epididymal sperm from chemically or surgically denervated rats displayed normal fertilization ability (80%) using in utero inseminations. In addition, the sperm of denervated rats did not show abnormal sperm chromatin structure using an assay that detects DNA damage. We conclude that sympathectomy delays the transit of sperm through the cauda epididymidis and produces ejaculatory dysfunction but does not compromise sperm quality in the distal cauda epididymidis. Moreover, these data provide compelling evidence that there is no association between the prolonged transit time of sperm within the epididymis, i.e., pre-ejaculatory sperm aging, and the fertility of those sperm, which has important implications for artificial insemination using sperm from men with SCI.

The Effects of a 785-nm AlGaInP Laser on the Regeneration of Rat Anterior Tibialis Muscle After Surgically-Induced Injury

Objective: This study aims to investigate the effects of low-level laser therapy (LLLT) on muscle regeneration. For this purpose, the anterior tibialis muscle of 48 male Wistar rats received AlGaInP laser treatment (785 nm) after surgically-induced injury.Background Data: Few studies have been conducted on the effects of LLLT on muscle regeneration at different irradiation doses.Materials and Methods: The animals were randomized into four groups: uninjured rats (UN); uninjured and laser-irradiated rats (ULI); injured rats (IN); and injured and laser-irradiated rats (ILI). The direct contact laser treatment was started 24 h after surgery. An AlGaInP diode laser emitting 75 mW of continuous power at 785 nm was used for irradiation. The laser probe was placed at three treatment points to deliver 0.9 J per point, for a total dose of 2.7 J per treatment session. The animals were euthanized after treatment sessions 1, 2, and 4. Mounted sections were stained with hematoxylin and eosin and used for quantitative morphological analysis, in which the number of leukocytes and fibroblasts were counted over an area of 4480 mu m(2). The data were statistically analyzed by analysis of variance (ANOVA) and the Bonferroni t-test.Results: Quantitative data showed that the number of both polymorphonuclear and mononuclear leukocytes in the inflammatory infiltrate at the injury site was smaller in the ILI(1), ILI(2), and ILI(4) subgroups compared with their respective control subgroups (IN(1), IN(2), and IN(4)) for sessions 1, 2, and 4, respectively (p < 0.05). on the other hand, the number of fibroblasts increased after the fourth treatment session (p < 0.05). With regard to the regeneration of muscle fibers following injury, only after the fourth treatment session was it possible to find muscle precursor cells such as myoblasts and some myotubes in the ILI(4) subgroup.Conclusion: During the acute inflammatory phase, the AlGaInP laser treatment was found to have anti-inflammatory effects, reducing the number of leukocytes at the injury site and accelerating the regeneration of connective tissue.

Murine model of surgically induced acute aortic dissection type A

This study aimed at developing a murine model of surgically induced acute aortic dissection type A for investigation of the formation and progression of acute aortic dissection and to test whether this system could be used for biomarker discovery.

Toric implantable collamer lens for moderate to high myopic astigmatism: 3-year follow-up

Background To evaluate the 3-year clinical outcomes after toric implantable collamer lens (ICL) implantation for the management of moderate to high myopic astigmatism. Methods Thirty-four eyes of 20 patients who underwent toric ICL implantation were reviewed. All eyes completed 3-year follow-up. Uncorrected (UDVA) and corrected (CDVA) distance LogMAR visual acuities, refraction, endothelial cell density (ECD), and surgical complications were evaluated. Vectorial analysis of astigmatic correction was also done. Results A significant improvement in UDVA, CDVA, manifest spherical and cylindrical refraction was observed at 1 week and remained stable after 3 years. Twenty-six eyes (76.5 %) gained lines of CDVA, and two eyes (5.9 %) showed a loss of 1 line of CDVA. The spherical equivalent (SE) was within ±0.50 D of emmetropia in 18 eyes (52.9 %) and within ±1.00 D in 28 eyes (82.4 %). Differences between target-induced astigmatism (TIA) and surgically-induced astigmatism (SIA) were statistically significant (p < 0.01), and a trend to undercorrection of the refractive astigmatism was present after 3 years. The magnitude of flattening effect (FE) was found to be significantly lower than the magnitude of TIA (p < 0.01). The magnitude of the torque vector was always positive, with a value below 0.50 D in all cases. No vision-threatening complications were observed during the follow-up. Conclusion Toric ICL implantation is an effective and safe surgical option that provides a relatively predictable and stable refractive correction of myopic astigmatism. Further improvements are needed to minimize the degree of undercorrection.

Clinical evaluation of three incision size-dependent phacoemulsification systems.

PURPOSE:

To compare the outcomes of cataract surgery performed with 3 incision size-dependent phacoemulsification groups (1.8, 2.2, and 3.0 mm).

DESIGN:

Prospective randomized comparative study.

METHODS:

One hundred twenty eyes of 120 patients with age-related cataract (grades 2 to 4) were categorized according to the Lens Opacities Classification System III. Eligible subjects were randomly assigned to 3 surgical groups using coaxial phacoemulsification through 3 clear corneal incision sizes (1.8, 2.2, and 3.0 mm). Different intraoperative and postoperative outcome measures were obtained, with corneal incision size and surgically induced astigmatism as the main clinical outcomes.

RESULTS:

There were no statistically significant differences in most of the intraoperative and postoperative outcome measures among the 3 groups. However, the mean cord length of the clear corneal incision was increased in each group after surgery. The mean maximal clear corneal incision thickness in the 1.8-mm group was significantly greater than for the other groups at 1 month. The mean surgically induced astigmatism in the 1.8- and 2.2-mm groups was significantly less than that in the 3.0-mm group after 1 month, without significant difference between the 1.8- and 2.2-mm groups.

CONCLUSIONS:

With appropriate equipment, smaller incisions may result in less astigmatism, but the particular system used will influence incision stress and wound integrity, and may thus limit the reduction in incision size and astigmatism that is achievable.

Facoemulsificação por córnea clara no meridiano mais curvo

OBJETIVOS: Avaliar o efeito da facoemulsificação com incisão em córnea clara no meridiano mais curvo sobre a magnitude do astigmatismo ceratométrico pré-operatório. Mapear a magnitude do astigmatismo cirurgicamente induzido por incisões nas posições nasal (N), temporal (T), temporal superior (TS) e temporal inferior (TI). MÉTODOS: Foi realizado estudo ceratométrico prospectivo em 48 olhos de 48 pacientes, submetidos a facoemulsificação com incisão do meridiano mais curvo. As medidas ceratométricas foram realizadas no pré-operatório e um mês após a realização da cirurgia. O astigmatismo cirurgicamente induzido foi determinado pelo método das coordenadas retangulares em 10 passos, modificado. RESULTADOS: Foram operados 21 olhos direitos e 27 olhos esquerdos e, de acordo com a posição das incisões em córnea clara, foram divididos em: 16 olhos N, 4 olhos T, 22 olhos TS, 6 olhos TI. A média da ametropia cilíndrica pré-operatória foi de 1,06D ± 0,65 e a pós-operatória de 0,89D ± 0,80. Houve diminuição estatisticamente significativa no astigmatismo corneal preexistente (p=0,016). A média total de astigmatismo cirurgicamente induzido foi de 0,94D ± 0,56. em relação aos grupos o astigmatismo cirurgicamente induzido foi de 1,06D ± 0,66 em N, 0,87D ± 0,20 em T, 0,95D ± 0,55 em TS e 0,61D ± 0,25 em TI. Não houve diferença estatística com relação ao astigmatismo cirurgicamente induzido nos grupos N, T, TS e TI (p=0,426). CONCLUSÃO: A técnica se mostrou efetiva na redução do astigmatismo ceratométrico pré-operatório. A média do astigmatismo cirurgicamente induzido foi de 1,06D ± 0,66 em N, 0,95D ± 0,55 em TS, 0,61D ± 0,25 em T e 0,87D ± 0,20 em TI.

Retinoscopia com luz em faixa em cães fácicos, afácicos e pseudofácicos

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Avaliação do erro refracional por retinoscopia com luz em faixa em cães fácicos, afácicos e pseudofácicos

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Body contouring surgery following bariatric surgery and dietetically induced massive weight reduction: a risk analysis

BACKGROUND: This study analyzed the impact of weight reduction method, preoperative, and intraoperative variables on the outcome of reconstructive body contouring surgery following massive weight reduction. METHODS: All patients presenting with a maximal BMI >/=35 kg/m(2) before weight reduction who underwent body contouring surgery of the trunk following massive weight loss (excess body mass index loss (EBMIL) >/= 30%) between January 2002 and June 2007 were retrospectively analyzed. Incomplete records or follow-up led to exclusion. Statistical analysis focused on weight reduction method and pre-, intra-, and postoperative risk factors. The outcome was compared to current literature results. RESULTS: A total of 104 patients were included (87 female and 17 male; mean age 47.9 years). Massive weight reduction was achieved through bariatric surgery in 62 patients (59.6%) and dietetically in 42 patients (40.4%). Dietetically achieved excess body mass index loss (EBMIL) was 94.20% and in this cohort higher than surgically induced reduction EBMIL 80.80% (p < 0.01). Bariatric surgery did not present increased risks for complications for the secondary body contouring procedures. The observed complications (26.9%) were analyzed for risk factors. Total tissue resection weight was a significant risk factor (p < 0.05). Preoperative BMI had an impact on infections (p < 0.05). No impact on the postoperative outcome was detected in EBMIL, maximal BMI, smoking, hemoglobin, blood loss, body contouring technique or operation time. Corrective procedures were performed in 11 patients (10.6%). The results were compared to recent data. CONCLUSION: Bariatric surgery does not increase risks for complications in subsequent body contouring procedures when compared to massive dietetic weight reduction.

Surgically created neural pathways mediate visual pattern discrimination

Combined lesions of retinal targets and ascending auditory pathways can induce, in developing animals, permanent retinal projections to auditory thalamic nuclei and to visual thalamic nuclei that normally receive little direct retinal input. Neurons in the auditory cortex of such animals have visual response properties that resemble those of neurons in the primary visual cortex of normal animals. Therefore, we investigated the behavioral function of the surgically induced retino-thalamo-cortical pathways. We showed that both surgically induced pathways can mediate visually guided behaviors whose normal substrate, the pathway from the retina to the primary visual cortex via the primary thalamic visual nucleus, is missing.

The effect of simulated astigmatic refractive error on reading performance

Background: Few studies have specifically investigated the functional effects of uncorrected astigmatism on measures of reading fluency. This information is important to provide evidence for the development of clinical guidelines for the correction of astigmatism. Methods: Participants included 30 visually normal, young adults (mean age 21.7 ± 3.4 years). Distance and near visual acuity and reading fluency were assessed with optimal spectacle correction (baseline) and for two levels of astigmatism, 1.00DC and 2.00DC, at two axes (90° and 180°) to induce both against-the-rule (ATR) and with-the-rule (WTR) astigmatism. Reading and eye movement fluency were assessed using standardized clinical measures including the test of Discrete Reading Rate (DRR), the Developmental Eye Movement (DEM) test and by recording eye movement patterns with the Visagraph (III) during reading for comprehension. Results: Both distance and near acuity were significantly decreased compared to baseline for all of the astigmatic lens conditions (p < 0.001). Reading speed with the DRR for N16 print size was significantly reduced for the 2.00DC ATR condition (a reduction of 10%), while for smaller text sizes reading speed was reduced by up to 24% for the 1.00DC ATR and 2.00DC condition in both axis directions (p<0.05). For the DEM, sub-test completion speeds were significantly impaired, with the 2.00DC condition affecting both vertical and horizontal times and the 1.00DC ATR condition affecting only horizontal times (p<0.05). Visagraph reading eye movements were not significantly affected by the induced astigmatism. Conclusions: Induced astigmatism impaired performance on selected tests of reading fluency, with ATR astigmatism having significantly greater effects on performance than did WTR, even for relatively small amounts of astigmatic blur of 1.00DC. These findings have implications for the minimal prescribing criteria for astigmatic refractive errors.

In vivo confocal microscopy of the ocular surface : from bench to bedside

In vivo confocal microscopy (IVCM) is an emerging technology that provides minimally invasive, high resolution, steady-state assessment of the ocular surface at the cellular level. Several challenges still remain but, at present, IVCM may be considered a promising technique for clinical diagnosis and management. This mini-review summarizes some key findings in IVCM of the ocular surface, focusing on recent and promising attempts to move “from bench to bedside”. IVCM allows prompt diagnosis, disease course follow-up, and management of potentially blinding atypical forms of infectious processes, such as acanthamoeba and fungal keratitis. This technology has improved our knowledge of corneal alterations and some of the processes that affect the visual outcome after lamellar keratoplasty and excimer keratorefractive surgery. In dry eye disease, IVCM has provided new information on the whole-ocular surface morphofunctional unit. It has also improved understanding of pathophysiologic mechanisms and helped in the assessment of prognosis and treatment. IVCM is particularly useful in the study of corneal nerves, enabling description of the morphology, density, and disease- or surgically induced alterations of nerves, particularly the subbasal nerve plexus. In glaucoma, IVCM constitutes an important aid to evaluate filtering blebs, to better understand the conjunctival wound healing process, and to assess corneal changes induced by topical antiglaucoma medications and their preservatives. IVCM has significantly enhanced our understanding of the ocular response to contact lens wear. It has provided new perspectives at a cellular level on a wide range of contact lens complications, revealing findings that were not previously possible to image in the living human eye. The final section of this mini-review provides a focus on advances in confocal microscopy imaging. These include 2D wide-field mapping, 3D reconstruction of the cornea and automated image analysis.

Matrix metalloproteinase 13-deficient mice are resistant to osteoarthritic cartilage erosion but not chondrocyte hypertrophy or osteophyte development

Objective To investigate the role of matrix metalloproteinase 13 (MMP-13; collagenase 3) in osteoarthritis (OA). Methods OA was surgically induced in the knees of MMP-13-knockout mice and wild-type mice, and mice were compared. Histologic scoring of femoral and tibial cartilage aggrecan loss (0-3 scale), erosion (0-7 scale), and chondrocyte hypertrophy (0-1 scale), as well as osteophyte size (0-3 scale) and maturity (0-3 scale) was performed. Serial sections were stained for type X collagen and the MMP-generated aggrecan neoepitope DIPEN. Results Following surgery, aggrecan loss and cartilage erosion were more severe in the tibia than femur (P < 0.01) and tibial cartilage erosion increased with time (P < 0.05) in wild-type mice. Cartilaginous osteophytes were present at 4 weeks and underwent ossification, with size and maturity increasing by 8 weeks (P < 0.01). There was no difference between genotypes in aggrecan loss or cartilage erosion at 4 weeks. There was less tibial cartilage erosion in knockout mice than in wild-type mice at 8 weeks (P < 0.02). Cartilaginous osteophytes were larger in knockout mice at 4 weeks (P < 0.01), but by 8 weeks osteophyte maturity and size were no different from those in wild-type mice. Articular chondrocyte hypertrophy with positive type X collagen and DIPEN staining occurred in both wild-type and knockout mouse joints. Conclusion Our findings indicate that structural cartilage damage in a mouse model of OA is dependent on MMP-13 activity. Chondrocyte hypertrophy is not regulated by MMP-13 activity in this model and does not in itself lead to cartilage erosion. MMP-13 deficiency can inhibit cartilage erosion in the presence of aggrecan depletion, supporting the potential for therapeutic intervention in established OA with MMP-13 inhibitors.

Visual no-man’s land

Professor Nathan Efron recounts his experience in ‘visual no-man’s land’ – a particularly stressful phase of his ophthalmic journey of retinopexy, cryopexy, vitrectomy and IOL surgery attributed to extreme surgically-induced anisometropia.