Rhazes' (865-925 CE) contribution to surgery in Liber Almansoris.

BACKGROUND: Surgery has deep historical roots. Rhazes (865-925 CE), a Persian physician, made a significant contribution to the development of medical sciences in the medieval era. Liber Almansoris is one of his significant works on medicine. This book is a medical textbook for medical students. It covers every aspect of the medical sciences. This article discusses Rhazes' contribution to surgery, based on Liber Almansoris. METHOD: This study examines Rhazes' contribution to surgery, based on his book, Liber Almansoris. RESULTS: Rhazes's Liber Almansoris contains a chapter (seventh chapter) on orthopedics, which includes surgical approaches. This chapter also describes surgical procedures for traumas and skull fractures. In other chapters, he also recommends surgical options for treating certain complications when discussing different treatment methods. DISCUSSION: Although Rhazes mentioned surgical procedures as a medical treatment method, he did not include a separate chapter on surgery. This strategy can be found in his other medical works, such as Liber Continens or Al-Hawi. It appears that Rhazes adheres to the Galenic (Greek) perspective on surgery. In this context, surgery is not an independent major but a method that a physician can employ as needed. It differs from an alternative approach in that era that adheres to ancient Persian perspectives, which identified surgery as a major like other medical sciences disciplines.

Medical ethics considerations on artificial intelligence.

Artificial intelligence (AI) is currently one of the mostly controversial matters of the world. This article discusses AI in terms of the medical ethics issues involved, both existing and potential. Once artificial intelligence is fully developed within electronic systems, it will afford many useful applications in many sectors ranging from banking, agriculture, medical procedures to military operations, especially by decreasing the involvement of humans in critically dangerous activities. Robots as well as computers themselves are embodiments of values inasmuch as they entail actions and choices, but their practical applications are modelled or programmed by the engineers building the systems. AI will need algorithmic procedures to ensure safety in the implementation of such systems. The AI algorithms written could naturally contain errors that may result in unforeseen consequences and unfair outcomes along economic and racial class lines. It is crucial that measures be taken to monitor technological developments ensuring preventative and precautionary safeguards are in place to safeguard the rights of those involved against direct or indirect coercion. While it is the responsibility of AI researchers to ensure that the future impact is more positive than negative, ethicists and philosophers need to be deeply involved in the development of such technologies from the beginning.

YKL-40 is a local marker for inflammation in patients with pseudoexfoliation syndrome.

PURPOSE: To investigate the YKL-40, as a marker of inflammation, in aqueous humor and serum of cataract patients with and without pseudoexfoliation syndrome (PEX). METHODS: Aqueous humor and serum samples were obtained from 44 patients who underwent phacoemulsification surgery. All patients were divided into two groups: PEX (n = 24) and control (n = 20). YKL-40 levels were measured with enzyme-linked immunosorbent assay (ELISA). The differences between the groups were assessed by using Chi-square and independent sample t-tests. The Pearson correlation coefficient was used to evaluate the correlation between variables. RESULTS: There was a significant difference between the mean YKL-40 levels in the aqueous humor of PEX group (112.0 ± 35.8 ng/mL) and control subjects (88.2 ± 30.6 ng/mL) (P = 0.025). However, the difference between the mean YKL-40 levels in the serum of PEX group (53.5 ± 29.1 ng/mL) and control subjects (44.6 ± 30.2 ng/mL) was non-significant (P = 0.326). The correlation between aqueous humor and serum YKL-40 concentrations was significant in both the groups (r = 0.833, P < 0.001; r = 0.840, P < 0.001, respectively). CONCLUSIONS: Increased aqueous humor levels of YKL-40 demonstrate that it is local, but not a systemic marker for inflammation in patients with PEX.

Ethical considerations on novel neuronal interfaces.

Wireless powered implants, each smaller than a grain of rice, have the potential to scan and stimulate brain cells. Further research may lead to next-generation brain-machine interfaces for controlling prosthetics, exoskeletons, and robots, as well as "electroceuticals" to treat disorders of the brain and body. In conditions that can be particularly alleviated with brain stimulation, the use of such mini devices may pose certain challenges. Health professionals are becoming increasingly more accountable in decision-making processes that have impacts on the life quality of individuals. It is possible to transmit such stimulation using remote control principles. Perhaps, the most important concern regarding the use of these devices termed as "neural dust" is represented by the possibility of controlling affection and other mental functions via waves reaching the brain using more advanced versions of such devices. This will not only violate the respect for authority principle of ethics, but also medical ethics, and may potentially lead to certain incidents of varying vehemence that may be considered illegal. Therefore, a sound knowledge and implementation of ethical principles is becoming a more important issue on the part of healthcare professionals. In both the ethical decision-making process and in ethical conflicts, it may be useful to re-appraise the principles of medical ethics. In this article, the ethical considerations of these devices are discussed.

Tear osmolarity and ocular surface changes in patient with polycystic ovary syndrome.

PURPOSE: To evaluate the tear osmolarity and ocular surface changes in patients with polycystic ovary syndrome (PCOS). MATERIALS AND METHODS: Forty-eight patients with recently diagnosed PCOS and thirty-three control volunteers were enrolled in this prospective, observational study. Ocular surface disease index (OSDI) score was calculated. Tear osmolarity was measured using the TearLab Osmolarity System (Tearlab, San Diego, CA, USA). All subjects also underwent the following ophthalmologic evaluation: Schirmer I test, tear-film breakup time (TBUT), ocular surface flourescein staining, and conjunctival impression cytology. RESULTS: Mean OSDI score was significantly higher in patients with PCOS than control subjects (P = 0.001). Tear osmolarity was similar in both groups (P = 0.404). There were no significant differences between groups in Schirmer I test results, TBUT, and ocular surface flourescein staining scores (P > 0.05). Compared to control group, a statistically significant squamous metaplasia was observed in temporal bulbar conjunctival impression cytology specimens in PCOS group (P = 0.032). CONCLUSIONS: In patients with recently diagnosed PCOS, tear volume and osmolarity are not affected but, conjunctival morphology may be affected, though on a limited scale.

Endothelial cell loss: Biaxial small-incision torsional phacoemulsification versus biaxial small-incision longitudinal phacoemulsification.

PURPOSE: To compare clinical results of biaxial small-incision torsional phacoemulsification and biaxial small-incision longitudinal phacoemulsification. SETTING: Department of Ophthalmology, School of Medicine, Namik Kemal University, Tekirdag, Turkey. DESIGN: Randomized controlled clinical trial. METHODS: Eyes with high-density nuclear cataract were assigned to have biaxial longitudinal (microburst mode) or biaxial torsional phacoemulsification. The main outcomes included corrected distance visual acuity (CDVA), central corneal thickness (CCT), central endothelial cell density (ECD), total ultrasound time (UST), cumulative dissipated energy (CDE), percentage total equivalent power in position 3, and balanced salt solution volume. Postoperative follow-up was at 1 day, 1 week, and 1 and 3 months. RESULTS: Each group comprised 35 patients (35 eyes). Three months postoperatively, the mean CDVA for each group was 0.02 logMAR and the mean CCT returned to the preoperative level (P=.589 and P=.554, respectively). During the postoperative follow-up, the percentage of mean endothelial cell loss in both groups was between 35.4% and 39.1%; there was no statistically significant difference between the groups (P>.05). The mean CDE, UST, percentage total equivalent power in position 3, and balanced salt solution volume values were similar in the 2 groups (P>.05). CONCLUSION: The risk for high endothelial cell loss should be considered when the phacoemulsification of high-density nuclear cataracts is performed using either method. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

Comparison of keratometric data obtained by automated keratometer, Dicon CT 200, Allegro Topolyzer, and Pentacam.

PURPOSE: To compare the keratometric values measured by the automated keratometer, two Placido-based computerized topography systems (Dicon CT 200 [Vismed Inc] and Allegro Topolyzer [WaveLight Inc]), and Scheimpflug analysis (Pentacam [Oculus Optikgeräte GmbH]). METHODS: The keratometric data of 200 eyes from 200 patients evaluated for refractive surgery were reviewed retrospectively. Mean simulated keratometry (Sim K) and mean corneal astigmatism measured by the four devices were compared using repeated measures analysis of variance with Bonferroni correction. The analysis of agreement between two measurements was assessed using the method of Bland and Altman. RESULTS: Mean Sim K as measured by the automated keratometer, Dicon CT 200, Allegro Topolyzer, and Pentacam was 43.39±1.50 diopters (D), 43.55±1.50 D, 43.45±1.50 D, and 43.43±1.45 D, respectively. The Dicon CT 200 measured the mean Sim K to be steeper and the automated keratometer measured the mean Sim K to be flatter than the other devices. Significant differences in corneal astigmatism were noted among the four devices except Dicon CT 200 versus Allegro Topolyzer and Allegro Topolyzer versus Pentacam comparisons (P<.013). For mean Sim K, the 95% limits of agreement between the Pentacam and other three devices were significantly wider than the other comparisons. In Bland-Altman plots comparing the Pentacam to the other devices, extreme outliers were present in 11 (5.5%) eyes. CONCLUSIONS: Because of the wide distribution range and presence of extreme outliers, Pentacam data should be used cautiously in IOL power calculation and astigmatic keratotomy procedures.

Intravitreal tigecycline treatment in experimental Acinetobacter baumannii endophthalmitis.

PURPOSE: To investigate the clinical and microbiological effectivity of intravitreal tigecycline in an experimental rabbit endophthalmitis model caused by imipenem resistant Acinetobacter baumannii. MATERIALS AND METHODS: Forty-eight eyes of 24 New Zealand white albino rabbits were divided into six groups (n=8 in each). The right eyes were divided into three groups and defined as infected group; left eyes were divided into three groups and defined as uninfected group. Infected group received 0.1 ml intravitreal A. baumannii suspension. Twenty-four hours after bacterial inoculation, group 1 received 1 mg/0.1 ml tigecycline and group 2 received 0.5 mg/0.1 ml tigecycline. Group 3 eyes received no treatment. In group 4, 0.1 ml of saline solution was injected. Groups 5 and 6 were received intravitreal tigecycline injection of 1 mg/0.1 ml and 0.5 mg/0.1 ml respectively. The eyes were enucleated for histopathological evaluation on the sixth day. Clinical and histological scoring systems were used to evaluate clinical and histological severity of the intraocular infection. RESULTS: The mean clinical scores of the six groups at the sixth day were 11±1.92, 12.4±6.2, 8.5±2.7, 0, 3±1.3, and 3±1.4 respectively. Mean histopathological scores were 7.8±2.8, 7.0±1.5, 5.6±1.4, 0, 0, and 0 respectively. There was no significant difference in mean clinical and histopathological scores of infected group (groups 1, 2 and 3). There was significant difference in mean clinical scores of groups 5 and 6 compared with group 4. Groups 4, 5 and 6 showed normal histological structure in histopathological evaluation and showed no significant difference. Microbiological cure was achieved in all infected eyes. CONCLUSIONS: Experimental rabbit endophthalmitis model caused by imipenem resistant A. baumannii was microbiologically cured by intravitreal tigecycline injection. However, a hypersensitivity-like reaction due to intravitreal application of tigecycline limits the use of this antimicrobial agent in A. baumannii endophthalmitis.

23-Gauge transconjunctival sutureless vitrectomy for retained lens fragments after complicated cataract surgery.

PURPOSE: The purpose of this study was to evaluate the effectiveness and safety of 23-gauge (23-G) transconjunctival sutureless vitrectomy in patients with retained lens fragments after complicated cataract surgery. METHODS: In this retrospective consecutive case series, 17 eyes of 17 patients with retained lens fragments after complicated cataract surgery and managed by using 23-G transconjunctival sutureless vitrectomy were evaluated between January 2007 and March 2009 at our institution. RESULTS: Mean follow-up time was 8.5 ± 3.00 months. Nine patients (53%) were pseudophakic, and 8 (47%) were aphakic. A foldable acrylic intraocular lens was implanted in eight eyes with aphakia. In 2 eyes (11.8%), one of 23-G sclerotomy port was enlarged and intravitreal phacoemulsification was performed with 20-gauge phacofragmatome to remove hard nucleus. Visual acuity improved in 100% of eyes and was 20/40 or better in 70.6% of eyes. Postoperative complications were transient elevation of intraocular pressure (29.4%), decentralization of the intraocular lens (5.9%), fibrin reaction (5.9%), mild vitreous hemorrhage (5.9%), and macular retinal pigment epithelial changes (5.9%). CONCLUSION: Twenty-three-gauge transconjunctival sutureless vitrectomy was observed to be effective and safe in patients with retained lens fragments after complicated cataract surgery. In cases with hard nucleus, 23-G vitrectomy probe may not be adequate to remove the lens fragments.

Outcome of surgery in long-standing infantile esotropia with cross fixation.

BACKGROUND: This is a retrospective study to determine the outcomes of the surgical correction in long-standing infantile esotropia with cross fixation. METHODS: Medical charts of a group of patients with esotropia who had cross fixation and underwent surgery for strabismus between January 1991 and December 2004 were reviewed. The mean follow-up time was 4.7 years. Binocularity was measured by the Worth 4-dot test and Titmus stereo test. Twenty-six patients underwent surgery for strabismus. Twenty-one patients aged 8 to 26 years with a minimum 3-year postoperative follow-up were included. Five patients were excluded because they were lost to follow-up after surgery. RESULTS: Bimedial recession and resection of one lateral rectus muscle were performed in all patients. Recession of the inferior oblique muscle with anteriorization was performed in patients who had inferior oblique overaction. Orthotropia was attained in 14 patients, whereas residual esotropia was diagnosed in 5 patients. Two patients were diagnosed as having exotropia. Two patients required a second surgery for dissociated vertical deviation. Overall, 9 of the 21 patients had indications of binocular function and 12 remained the same in their stereoacuity. CONCLUSION: Surgical correction of long-standing infantile esotropia with cross fixation in young adults may improve binocular function and allow long-term alignment stability.

Macular thickness changes after phacoemulsification in previously vitrectomized eyes for diabetic macular edema.

PURPOSE: To report visual results and anatomical outcome after uncomplicated phacoemulsification in eyes that previously underwent pars plana vitrectomy for diabetic macular edema. METHODS: This retrospective noncomparative study included 22 eyes of 19 diabetic patients who underwent uncomplicated cataract surgery with phacoemulsification and intraocular lens implantation after pars plana vitrectomy with internal limiting membrane removal for diabetic macular edema. Main outcome measures included visual acuity and foveal thickness (FT) changes as assessed by optical coherence tomography. Wilcoxon test was used for statistical analysis. RESULTS: Mean follow-up time was 11.9 ± 8.75 months. Mean FT increased by 20.5 ± 67.6 µm (8.4%), with a mean preoperative FT of 237 ± 69 µm compared with a mean postoperative FT of 257.6 ± 89.8 µm (P = 0.236). Foveal thickness increased by at least 20% in 6 eyes (27.3%), remained within 20% in 14 eyes (63.6%), and decreased by 20% in 2 eyes (9.1%). Visual acuity improved by ≥2 lines in 16 eyes (72.7%) and remained stable in 6 eyes (27.3%). Visual acuity was 20/40 or better in 11 eyes (50%). CONCLUSION: Moderate but insignificant increase in FT was observed after phacoemulsification in eyes that previously underwent pars plana vitrectomy for diabetic macular edema. Prospective studies with a large number of patients are warranted for a more reliable conclusion.

Anterior transposition of the inferior oblique muscle in the treatment of unilateral superior oblique palsy.

PURPOSE: To determine whether unilateral inferior oblique anterior transposition alone could be an effective procedure for treating superior oblique palsy with inferior oblique overaction. METHODS: The records of 38 patients who underwent unilateral inferior oblique anterior transposition for unilateral superior oblique palsy with inferior oblique overaction were evaluated. A comprehensive ocular examination including best-corrected visual acuity measurements, ductions, versions, and deviations at near and distance, head tilt test, abnormal head position, dilated fundus examination, and Titmus test was performed prior to and after surgery. RESULTS: The mean patient age was 29 years, the mean follow-up was 32 months, the mean preoperative hypertropia in primary position was 14.29 ± 7.7 prism diopters (PD), and the mean inferior oblique overaction was 3.63 ± 0.67. Anterior transposition of the inferior oblique muscle was effective across a wide range of preoperative primary position hypertropia (4 to 35 PD) with a mean reduction in postoperative hypertropia of 12 PD. Inferior oblique overaction was reduced in all patients. No patient demonstrated postoperative primary position hypotropia. Surgery improved stereoacuity nearly two units using the Titmus stereoacuity scale. CONCLUSION: Anterior transposition of the inferior oblique muscle is effective in correcting inferior oblique overaction and primary position hypertropia in the treatment of unilateral superior oblique palsy.

Long-term outcome of a silicone expander for Brown's syndrome.

PURPOSE: Assessment of the long-term outcome of a silicone tendon expander for Brown's syndrome. PATIENTS AND METHODS: Records of 22 eyes of 16 patients with the diagnosis of Brown's syndrome were reviewed. Patients who had previous superior oblique (SO) muscle surgery or previous or concurrent surgery on another muscle were not included. The average follow-up period was 58.4 months. The SO tendon was cut approximately 5 mm away from the nasal border of the superior rectus muscle. The expander, which varied from 5 to 7 mm in length, was placed in the tenotomized SO muscle tendon. RESULTS: Elevation in adduction was obtained in all patients who underwent surgery. One eye had undercorrection, one eye had limitation in downgaze, and three eyes had overcorrection postoperatively. Six eyes had a severe postoperative inflammatory reaction that was successfully treated with topical corticosteroids and oral nonsteroidal anti-inflammatory drugs. Six eyes had foreign body sensation that resolved in time. In two eyes, consecutive SO palsy developed. One eye was reoperated for extrusion and the silicone bands were removed from two eyes; these eyes improved in 2 to 4 months. CONCLUSION: Silicone expander surgery is a challenging procedure used to treat Brown's syndrome. No cyclotorsion occurred after this surgery. This procedure is reversible and repeatable. A learning period is required to obtain the skill needed to avoid entering the sub-Tenon space.

Long-term results of bilateral medial rectus recession for congenital esotropia.

PURPOSE: This study assessed the long-term results of orthophoria obtained with bilateral medial rectus recession for congenital esotropia. PATIENTS AND METHODS: The medical records of 214 patients who underwent bilateral medial rectus muscle recession between January 1995 and January 2000 were reviewed. Patients were excluded if neurological abnormalities or developmental delays were documented and if structural eye abnormalities were present. Mean follow up was 54.2 months (range, 36 to 96 months). Rates of reoperation for residual esotropia, consecutive exotropia, oblique muscle overaction, or dissociated vertical deviation were determined. RESULTS: Forty-five (21%) patients underwent surgery for residual esotropia, 32 (15%) underwent surgery for consecutive exotropia or dissociated horizontal deviation, and 39 (18%) underwent surgery for oblique muscle overaction and dissociated vertical deviation. CONCLUSION: To maintain long-term alignment of congenital esotropia, additional surgical procedures may be required. The success rate of bilateral medial rectus recession for ocular realignment with one operation is approximately 50%. This method is quicker, simpler, and less traumatic than three or four muscle operations. In addition, the lateral rectus and oblique muscle are left unoperated for future surgeries if necessary.