Schiotz Tonometer Research Articles

Agreement of intraocular pressure measurement by scleral Schiotz and Goldmann applanation tonometer.

In this cross-sectional observational study, IOP was measured by GAT on the cornea and Schiotz tonometer on the temporal sclera. Axial length and central corneal thickness (CCT) were noted. IOP was then estimated from SS IOP as eGAT using a predictive formula. Agreement of IOP corrected for CCT (cGAT) with eGAT and SS IOP were assessed. The effects of age, axial length, refraction, CCT, gender, and ocular and systemic comorbidity on measured IOP were also assessed. The study included 155 patients with a mean age of 54.27 ± 10.02 years. Mean IOP measured by GAT and scleral Schiotz were 16.58 ± 2.76mm Hg and 16.10 ± 2.96mm Hg, respectively. The mean IOP by cGAT and eGAT were 16.70 ± 2.80mm Hg and 17.07 ± 3.10mm Hg, respectively. Both eGAT & SS IOP had good agreement with cGAT on the Bland-Altmann plot (p = 0.96 & 0.51, respectively). Further, SS IOP showed good agreement even with GAT IOP (p = 0.78). Age, axial length, refraction, central corneal thickness, gender, and ocular and systemic comorbidity did not show significant correlation with IOP measurement. Estimated GAT IOP showed good agreement with measured GAT values. SS IOP also agreed well with GAT IOP. Clinical significance IOP measurement on the sclera using Schiotz can be used as an alternative to GAT.

ACCURACY OF MEASUREMENT RESULTS ON SCHIOTZ TONOMETER TOWARDS GOLDMANN APPLANATION TONOMETER IN TYPE II DIABETES MELLITUS PATIENTS IN MOHAMMAD HOESIN HOSPITAL, PALEMBANG

Introduction & ObjectivesThe Goldmann Applanation Tonometer is now the most accurate gold standard compared to othertonometers. IOP measurement errors using the Schiotz Tonometer can be caused by ocular rigidity,where the IOP is read higher in eyes with higher ocular rigidity and vice versa. Type II DiabetesMellitus (DM) patients are at risk for increased ocular rigidity
 MethodsThis research is a cross-sectional study with a diagnostic test design regarding the accuracy ofintraocular pressure results on the Schiotz Tonometer against the Goldmann Applanation Tonometerin type II Diabetes Mellitus patients with 35 research samples. The research was conducted at theMohammad Hoesin Hospital in Palembang from April 2022 – September 2022 until the sample sizewas met
 ResultsIntraocular pressure (IOP) as measured by The average Goldmann Applanation Tonometer was 15.5± 2.4 mmHg, with a Schiotz load of 7.5 grams the average was 16.2 ± 2.3 mmHg. Ocular rigidityhad a median of 0.0242 (0.0176 – 0.0341) From the results of this study the IOP examination withthe Schiotz Tonometer had a sensitivity of 92.9%, a specificity of 80.9%, a positive predictive valueof 76.5%, a negative predictive value of 94.4% and an accuracy value of 92.3% indicating astatistically strong level of accuracy
 ConclusionThe Schiotz tonometer has an accuracy rate of 92.3% in examining intraocular pressure using a loadof 7.5 type II diabetes patients which can replace the Goldmann Applanation Tonometer as the goldstandard if normal ocular rigidity is found

Severe Case Of Delayed Diagnosed Of >10 Years Untreated Newborn Congenital Glaucoma

Introduction : Though cases of newborn primary congenital glaucoma (PCG) had poor prognosis, we couldn’t simply ignore that early proper diagnostic and treatment can still improves quality of one’s sight, which’s absent in this case. Presented with delayed diagnosed highly suspected case of newborn PCG, physician was compelled to make the best in condition of the already given poor prognosis to begin with.
 Case Illustration : A 13 years old female patient came to eye clinic with a very disturbing chronic condition of visual loss. Accompanied by her family, who also claimed had witnessed both the patient’s eyes appeared whitish since birth. Eye examination revealed visual acuity of 1/~ for right eye and no light perception for left eye, along with significant signs of buphthalmos, epiphora, nystagmus, megalocornea (diameter of 9x14mm right eye and 9x13.3mm left eye), cloudy cornea, leukocoria, and Schiotz tonometry of 60-100mmHg in both eyes. Patient then received oral Acetazolamide, Levofloxacin eye drop, and Timolol Maleate 0,5% eye drop; then advised to return for one week evaluation also to bring her siblings to be subjected to glaucoma screening.
 Discussion : The decision to perform surgical intervention in cases of newborn PCG commonly require further thoughts. This case immediately shifted our focus towards palliative care of the patient whilst continuing monitoring IOP, as glaucoma surgery possessed a more menacing risk to be performed this patient.
 Conclusion : All cases of pediatric glaucoma require a life time of comprehensive management that requires heedfulness especially from caregivers as it is a very challenging disease.

A Comparative Study of Intraocular Pressure Measurements by Goldmann Applanation Tonometer and Schiotztonometer and the Study of Schiotz Tonometer a Screening Tool in North Karnataka Population

Background: Glaucoma is a multifactorial disease with common end point characteristics affecting the optic nerve.It is defined as an optic neuropathy characterised by specific structural findings in the optic disc (increased VerticalCup Disc Ratio (VCDR) or VCDR asymmetry >97.5 percentile) and particular functional deficits in automatedvisual field testing. It consists of three components: the optic nerve head, the visualfield, and intraocular pressure.Detecting the intraocular pressure is essential in not only initiating treatment, but also in monitoring the responseto treatment.Method: 210 purposively selected patients were subjected to three methods of tonometry – Goldmannapplanationtonometry, Schiotz indentation tonometry (with the 5.5g, 7.5g and 10 g weights). Three recordings were obtainedwith each method and the arithmetic mean taken as the intraocular pressure. The data was statistically analyzedusing the intra-class correlation coefficient. Sensitivity and specificity were also calculated for the Schiotz tonometer.Results: The Schiotz tonometer showed fair agreement with the Gold mannapplanationtonometer. The Schiotztonometer scored low as an effective screening tool.Conclusion: The current study shows that the Schiotz tonometer compares favourably with theGoldmannapplanation tonometer showing fair agreement with it. It showed good specificity and was reliable indetection of positives, excluding false positives.

Management of aphakia with low corneal endothelial cell count after complicated cataract surgery in a middle-age patient

Background: secondary intraocular lens implantation becomes more challenging due to pre-existing conditions. Objective: To report the outcome of retropubic iris-claw intraocular lens (RP-ICIOL) to corrects aphakia with low corneal endothelial cell count following previous complicated cataract surgery. Case: A 32-year-old male was referred to Undaan Eye Hospital with a chief complaint of blurred vision in his left eye (LE). Previously, the patient was diagnosed with a mature subluxated cataract and has undergone cataract extraction on the LE. Visual acuity of LE was 1/60 with raised intraocular pressure (31,8 mmHg with Schiotz Tonometry). On anterior segment examination, there was a clear cornea with an oval pupil and aphakia. The examination of the posterior segment was within normal limits. Specular microscopy of LE was 1140 cells/mm2. After IOP was controlled by medication, the patient then underwent retropubic iris-claw intraocular lens implantation. Post-operatively, the visual acuity of the LE was 2/10 and the IOP was 11 mmHg using non-contact tonometry. Six weeks post-op, the best visual acuity (BCVA) was 9/10 and the IOP was 15 mmHg and the CECD was 1110 cells/mm2 on the LE. Discussion: The RP-ICIOL was maintaining the physiological condition of the IOL location posteriorly, thus minimizing the risk of corneal decompensation and increased postoperative intraocular pressure, while at the same time trying to achieve a good refractive outcome. Conclusion: The implantation of RP-ICIOL is safe and effective management of aphakia with a low corneal endothelial cell coun secondary intraocular lens implantation becomes more challenging.

EFFECT OF INHALED TIOTROPIUM ON INTRAOCULAR PRESSURE IN PATIENTS OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE

Introduction: Chronic Obstructive Pulmonary Disease is one of the leading causes of morbidity and mortality with increasing prevalence worldwide. Tiotropium bromide a long acting antimuscarinic agent used in management. In the eye it causes pupil dilation, leading to closure of anterior chamber angles, consequently leading to increased intra ocular pressure. Objectives: To study the effect of inhaled tiotropium on intraocular pressure in patients of Chronic Obstructive Pulmonary Disease. Methods: This is a prospective observational study done over a period of one year on 100 patients of Chronic Obstructive Pulmonary Disease using tiotropium inhaler and fulfilling the inclusion and exclusion criteria. Clinical details and other essential information had been collected using a proforma that was filled by the investigator. During study period tiotropium is administered at a dose of 18mcg/day. The Schiotz tonometer is used to assess intraocular pressure at baseline, at the end of 1 month and 3 month follow up period. The results were organized and analyzed statistically. Results: A total of 100 patients recruited for study which included 88 males and 12 females. Intra ocular pressure (IOP) of both eyes were compared in our study using Schiotz tonometer at baseline, one month and at end of follow up period of three months. We found a statistically significant difference in mean IOP by paired t-test at baseline and 3rd month, one month as well as three months, but changes in IOP was not significant between baseline and one month. Conclusion: We found a statistically significant difference in mean IOP by paired t-test at baseline and third month.

CLINICAL EVALUATION OF INTRAOCULAR PRESSURE MEASUREMENTS USING DIFFERENT TONOMETERS IN PATIENTS OF VARIOUS REFRACTIVE ERRORS

Background: Intraocular pressure (IOP)is an important rst indicator of probability and suspicion of Glaucoma. The virtual IOP status is grossly inuenced by multiple factors including Refractive errors, corneal biomechanics ,central corneal thickness(CCT) and Scleral rigidity. Aim: To compare relative IOP measurements and its variability in Emmetropes, myopic and hypermetropic patients using Schiotz, Goldmann Applanation(GAT)and I-Care Rebound tonometer to establish an equation between virtual and real time IOP. Materials and Methods: This observational prospective study comprised of 100 subjects above the age of 18 years inclusive37 Emmetropes , 31 Hypermetropes and remaining 32 belonged to myopia . Statistical Analysis : Descriptive statistics were performed using SPSS for Windows version 17.0 to calculate the demographic characteristics of the study cohort. The data were expressed as mean values including the standard deviation (SD) and the 95% condence interval (CI). Mean IOP measurements between Schiotz, I-Care and GAT were compared by One way ANOVA along with Individual pair wise comparison by applying Post Hoc Tukey Test for comparison of IOP measurements using a particular method of Tonometry in individuals of myopia, hypermetropia and emmetropia. Results: The highest mean value of CCT 536.667 mum was in Hypermetropes whereas the lowest CCT value of 507.031mum was in myopic eyes with statistically signicant (P<0.05). The mean value for IOP in Emmetropes was16.665 mm Hg for Schiotz , 15.027 Hg for GAT and 15.081 mm Hg for I –Care .Whereas Hypermetropes revealed mean value of 15.055 mm Hg for Schiotz , 14.323 mm Hg for GAT and 14.065 mm Hg for I –Care . The mean value for IOP in Myopic eyes was 16.875 mm Hg for Schiotz , 14.375 mm Hg for GAT and 14.688 mm Hg for I –Care . Conclusion : The study had revealed higher mean value of IOP in Myopic eyes as compare to Emetropic and Hypermetropic subjects. IOP measurements by the Schiotz tonometer were signicantly higher as compare to GAT and I-Care tonometer. Whereas recordings by GAT and I Care tonometers were almost in agreement .Denitive correlation could not be established between pachymetry readings and adjusted IOP following GAT and I –Care tonometry .

Outcomes of Paediatric Cataract Surgery in Southern Jordan

Background: Congenital cataract is the leading global cause of preventable childhood blindness, and the onset of infantile and congenital cataracts is rare. Managing congenital cataracts is still challenging due to associated complications. Objective: This study aimed to assess the outcomes of congenital cataract surgery with intraocular lens implantation in southern Jordan. Methods: A retrospective case series included 20 children with congenital cataracts who underwent lensectomy, aged between 1 to 5 years, recruited using a purposive sampling technique. The mean age was 2.9 years ± 1.4. Intraocular pressure was measured preoperatively at baseline and then every three months, followed up postoperatively until one year. Schiotz tonometer is used to measure intraocular pressure. Results: The distribution of IOP and change in IOP values at baseline and post-operative follow-ups showed statistically significantly higher IOP values at three months of follow-up (P=0.03) and the last follow-up visit at 12 months (P=0.001). The results showed a statistically significant increase from baseline in the IOP of the unilateral cataract eye compared to its normal fellow eye (P=0.028). The post-operative evaluation showed that 14 patients demonstrated twenty-seven post-operative complications. Four eyes (14.2%) with posterior synechiae, 2 (7.1%) with anterior synechiae, 3 (10.7%) with decentration of IOL, 8 (28.6%) with pigment on IOL, 3 (10.7%) with transient corneal oedema and 7 (25%) developed post-operative glaucoma. Conclusion: We concluded that post-operative follow-up of one year in pediatric patients treated with congenital cataract surgery showed a significant increase in intraocular pressure.

Tono-pen and Schiotz tonometer measurements in gas-filled eyes

This study aims to assess the difference between Tono-Pen and Schiotz tonometer measurements in gas-filled eyes and to create a nomogram and equation which can be used to estimate actual intraocular pressure in order to provide a safe IOP level at the end of the surgery. Twenty-two eyes that underwent pars plana vitrectomy were included in the study. Perioperative Tono-Pen and Schiotz tonometer measurements were performed when the eyes were filled with air in the setting of certain vitrectomy infusion pressure levels. Measurements were performed when the eyes were filled with fluid to test the accuracy of the systems. The mean value of the Tono-Pen and Schiotz readings in air-filled eyes corresponding to certain actual intraocular pressure levels were analyzed to create nomograms. Both Tono-Pen and Schiotz tonometers underestimated the actual intraocular pressure set on the screen of the vitrectomy system in the air-filled eyes. The Tono-Pen deviation was 4.5mmHg at a level of 15mmHg actual intraocular pressure, and 16.9mmHg at a level of 55mmHg actual intraocular pressure. The Schiotz tonometer deviation was 10mmHg at a level of 15mmHg actual intraocular pressure, and 8.9mmHg at a level of 55mmHg actual intraocular pressure. All the mean differences between tonometer readings and actual intraocular pressure were statistically significant. (P<0.001) CONCLUSION: To achieve an adequate and safe tamponade at an actual IOP range of 20 - 25mmHg, one should adjust the IOP with Schiotz readings to a level of 9-12mmHg, or Tono-Pen readings to 12-18mmHg.

A PROSPECTIVE STUDY OF MULTINATIONAL COMPANY WORKERS’ INTRAOCULAR PRESSURE

Objectives: The objective of this study were to find out differences in intraocular pressure (IOP) before and after computer usage and to find out differences in IOP in males and females. Computers have become such a vital part of our daily lives that it is often difficult for us to eliminate our use. The present age is regarded as the computer age. Most of our time goes looking at screens of different forms in laptops, desktop computers, tablets, and mobile phones. Computers use has become a necessity of the present-day world in various professions and it may sometimes require prolonged sessions which can produce strain on the eyes, liable to affect IOP. Methods: The present study includes 100 subjects between 20 and 40 years of age who works continuously for at least 4 h a day on computer screens and individuals without ophthalmological disorders. Schiotz tonometer was used to measure IOP by an ophthalmologist. Results: Our study sample contains 80% males and 20% females, with a manage of 29.29 and 27.55 years, respectively. The increase in IOP value of the left eye after exposure is comparatively more significant in the 6–10 years exposure group (p=0.0000). This finding is similar to the one obtained for the right eye. There is a significant increase in mean IOP values after computer exposure in both males and females. However, the increase is comparatively more significant in males compared to females. Conclusion: There will be a significant increase in IOP after Computer exposure in both genders with a comparatively greater rise of IOP in males than those in females.

Comparative study between schiotz tonometer and goldmann applanation tonometer in glaucomatous and normal individuals

Checking of intraocular pressure (IOP) is one of the basic investigations in a general ophthalmology work up. In this study we attempted to compare the IOP readings obtained by Goldmann applanation tonometer and Schiotz indentation tonometer in glaucomatous and normal individuals attending general ophthalmology OPD in a tertiary care centre in Central Rajasthan. It is a case series study in which IOP was checked in patients using two tonometers. Statistical analysis was done to evaluate the agreement between instruments.: In this study, when measured with Goldmann applanation tonometer (GAT), it was found that the mean IOP of both right and left eye in group A (Glaucomatous subjects) (24.19±12.94 and 23.34±13.73 respectively) was significantly higher than mean IOP of both right and left eye in group B(non glaucomatous subjects) (15.06±2.49 and 15.12±2.38 respectively). Likewise, when measured with Shiotz tonometer (ST), mean IOP of both right and left eye in group A (26.05±11.93 and 24.65±12.28 respectively) were very significantly higher in comparison to group B (16.79±2.64 and 16.85±2.47 respectively).The mean pressures obtained by the Schiotz tonometer were higher than the mean Goldmann pressures which indicate that the Schiotz tonometer tends to read higher than the Goldmann tonometer.

Trypsin dose optimization for glaucoma induction in rabbit model

Glaucoma is a neurodegenerative disease identified by optic nerve damage and loss of retinal ganglionic cells. The aim of the study was to test the precise dose of trypsin to induce glaucoma in a rabbit model. Nine White New Zealand rabbits were randomly divided into three groups: Group one (G1) normal animals as control, group two (G2) the animals were injected with 0.2 ml of 0.04% trypsin and group three (G3) injected with 0.2 ml of 0.05% trypsin into posterior chamber of eye. A schiotz tonometer was used to measure intraocular pressure (IOP) before the injection, two days after injection and once a week until the end of the second week. At the end of the second week, the histology of the retina and optic nerve was studied. G3's intraocular pressure increased by 43.7%, while G2's intraocular pressure increased by 0.7% compared to G1. Retinal ganglionic cells (RGCs) decreased in G3 by 91.5% and G2 by 43.8% in comparison with G1. Optic nerve histology in G3 displayed decreased Schwann cell quantity with vacuolation and low orientation of nerve fibers compared with G1 and G2. Group three had the highest increase in IOP due to obstruction of drainage canal and preventing outflow of aqueous humor. This resulted in mechanical compression on the retina, ending with loss of RGC and degeneration of the optic nerve. The conclusion is that 0.2ml of 0.05% trypsin is the proper dose for the induction of glaucoma.

A study to compare intraocular pressure using Perkins and Schiotz tonometer with respect to Goldmann applanation tonometer as a gold standard in a tertiary health care centre, Navi Mumbai

To compare IOP measurement of Perkin’s tonometer and Schiotz tonometer with respect to Goldmann applanation tonometer (GAT).100 eyes of 50 patients aged 18 to 65 years presenting to Ophthalmology OPD were selected by randomization and detailed general and ophthalmic examination was done. IOP was measured using applanation tonometers (Perkin’s and GAT) and indentation tonometer (Schiotz tonometer) in that order. The study population included 38 male eyes and 62 female eyes; 50 right eyes and 50 left eyes. There was a statistically highly significant difference seen for the values between the groups (p&amp;#60;0.01) with higher values in IOP measured by GAT followed by IOP measured by Perkin’s tonometer and least in IOP measured by Schiotz tonometer.There was a statistically non significant difference seen for the values between Perkin’s tonometer and GAT (p&amp;#62;0.05). While there was a statistically highly significant difference seen for the values between GAT and Schiotz tonometer (p&amp;#60;0.01).There was a statistically non significant difference seen for the IOP values between right eye and left eye. There was a statistically non significant difference seen for the IOP values between males and females. Measurement of IOP with Perkin’s was closer to the values obtained by GAT. Perkin’s being portable, easy to use and precise tonometer than Schiotz tonometer, can be considered as an excellent substitute to GAT, for large scale examination, if cost is not a concern.

Study of Occurrence of Cataract and their Surgical Management in Dogs

Background: Present study investigated the occurrence of cataract in dogs presented to the Teaching Veterinary Clinical Complex (TVCC) and Department of Veterinary Surgery and Radiology under Odisha University of Agriculture and Technology, Bhubaneswar during a period of four months. During the study period, a total number of 3847 canine cases were registered at TVCC, out of which 23 cases registered under the RKVY project for different types of ophthalmic affections. There were only eight canine cataract cases with overall prevalence of 0.2% among total canines presented to TVCC and 34.78% of total canines presented with some sorts of ophthalmic affections. Methods: Menace reflex, pupillary light reflex, maze test, obstacle test, catoptrics test, Schirmer’s tear test (STT), Schiotz tonometry, Slit lamp bio microscopy and fundus examination -using indirect ophthalmoscope (IO) and fundus camera, were carried out in all the cases studied. Result: Occurrence of cataract was higher in Spitz (50%). Males had more incidences (62.5%) of cataract. The ages of the dogs were less than 10 years. B mode ultra-sonographic (USG) examination revealed increased echogenecity of lens in all cataract affected dogs while corneal opacification was found in two cases. Cataract was extracted by phaco-emulsification in three dogs and by small incision cataract surgery (SICS) technique in one dog.

The effect of corneal crosslinking on the rigidity of the cornea estimated using a modified algorithm for the Schiøtz tonometer.

Purpose:The aim of this study was to test a method for estimating corneal rigidity before and after cross-linking (CXL) using a Schiøtz tonometer.Methods:The study was performed in the Kyiv City Clinical Ophthalmological Hospital “Eye Microsurgical Center”, Ukraine. This was a prospective, consecutive, randomized, masked, case-by-case, clinical study. Corneal rigidity, indicated by the gradient (G) between lg applied weight and corresponding lg scale reading during Schiøtz tonometry, were obtained by increasing (A-mode) then reducing (D-mode) weights by two operators [A] in keratoconus, post-CXL and control subjects for estimation of (i) interoperator and (ii) intersessional errors, (iii) intergroup differences; [B] before and after CXL. Central corneal thickness CCT was measured by scanning slit pachymetry. ANOVA, t tests, linear regression were the statistical tools used.Results:Average interoperator difference (ΔG) was –0.120 (SD = ±0.294, 95%CI = –0.175 to –0.066). A significant correlation between ΔG and the mean of each pair of G values was found (r = –0.196, n = 112, P = 0.038). Intersessional differences in mean G values were insignificant (P > 0.05). There was a significant correlation between G at first session (X1) and difference between sessions (ΔG) [Operator 1, ΔG = 0.598x1–0.461, r = 0.601, n = 27, P = 0.009]. Significant intergroup differences in G were found (Operator 1, one-way ANOVA, F = 4.489, P = 0.014). The difference (Δ) between the pre-(X2) and post-CXL treatment G values was significantly associated with the pre-CXL treatment value (Operator 1, Δ = 1.970x2-1.622, r = 0.642, n = 18, P = <.001). G values were correlated with CCT in keratoconus and post-CXL.Conclusion:Corneal rigidity (G) estimated using the Schiøtz tonometer can be useful for detecting changes after CXL. However, G values are linked to CCT, can vary from time-to-time and the procedure is operator dependent.

Chemical disinfectants in ophthalmic practice.

The instrumentation used in ophthalmic clinics can be a source of epidemics in health care set up. Contact tonometry with Schiotz or Applanation tonometer is associated with nosocomial epidemic keratoconjunctivitis outbreaks. Recently identified SARS-CoV-2 (COVID -19) spreads mainly via the respiratory route and fomites and can transmit through other body fluids, including tear film. Various ophthalmic instruments can become a common source of spreading cross infections. Chemical disinfection is one of the most common methods employed to decontaminate instruments and environmental surfaces and prevent transmission of infectious pathogens to patients through medical and surgical instruments. Various chemical disinfectants are available with a varied spectrum to work on a different group of organisms. In this article, we briefly cover commonly used chemical disinfectants in ophthalmic practice like Alcohol (Ethyl Alcohol, Isopropyl Alcohol), Chlorine-based solution (mainly Sodium Hypochlorite), Glutaraldehyde, Hydrogen Peroxide, Formaldehyde, Iodophors, and Quaternary Ammonium Compounds

Efficacy of dexmedetomidine premedication on attenuation of intraocular pressure changes after succinylcholine and endotracheal intubation

Introduction: Succinylcholine, is one of the most commonly used muscle relaxant for rapid sequence airway management. It increases the Intraocular pressure (IOP) which is deleterious in open globe injuries. We studied the effects of Inj. dexmedetomidine, a highly selective ?2-adrenoceptor agonist, on IOP and hemodynamic responses to succinylcholine and tracheal intubation. Materials and Methods: Sixty ASA I–II patients, scheduled for elective non-ophthalmic surgeries requiring general anesthesia were randomly premedicated by intravenous Inj. dexmedetomidine 0.4 µg/kg (Group-D) or saline (Group-S) (30 patients each group). Heart rate (HR), mean arterial pressure (MAP), and IOP (using Schiotz tonometer) were measured 10 minutes before and after the premedication, 30 seconds after succinylcholine and at 1, 5 and 10 minutes after intubation. Results: Ten minutes after Inj. dexmedetomidine administration, there was marked decrease in IOP. After intubation there was a rise in IOP, however it remained below baseline IOP (p=0.315) and remained low at 10th minute after intubation (p

A Novel and Simple Method to Assess Corneal Biomechanics Using Schiotz Tonometer

Background: The present study introduces a novel method to evaluate corneal biomechanics, which has a key role in diagnosing keratoconus (KC) or keratectasia (KE). Methods: In this multicentre, prospective, single-blind study, patients with myopia, cataracts, or KC underwent corneal biomechanics evaluation with a Schiotz tonometer, before and after corneal crosslinking (CXL) or Femtosecond assisted laser in situ keratomileusis (FS-LASIK). The corneal biomechanics metric (Mulee factor, MF) was calculated from the data obtained with the tonometer. Clinical significance was verified by analysis of the correlation of MF and ocular morphology metrics and efficiency of MF in predicting the occurrence of KC or KE. Findings: A negative relation was found between the MF and Young’s modulus (P<0·001) and MF and maximal stress (P<0·001) in an in vitro study on rabbit eyeballs. MF in normal eyes (myopia and cataract eyes) was 2·890·43. MF before FS-LASIK was 2·940·35, increasing to 3·710·42 one month after FS-LASIK (P<0·001). In the normal population, pre-operative MF was negatively correlated with age (P<0·001), positively correlated with central corneal thickness (P=0·03), but not related to anterior chamber depth, ocular axis length, intraocular pressure, cornea diameter, and cornea curvature. MF was 4·090·56, decreasing to 2·140·55 one month after CXL. MF was 3·360·51 in eyes with forme fruste keratoconus (FFKC). There were 3, 6, and 10 cases of KC or KE after FS-LASIK, CXL, or FFKC, respectively. The cut-off points for predicting KC or KE with MFs were 4·67, 2·67, and 3·5 in patients with FS-LASIK, KC, and FFKC (P<0·01, P<0·01, and P<0·01, respectively). Interpretation: The MF can sensitively reflect corneal biomechanics and is not influenced by ocular metrics. The MF predicts KC and KE with high specificity and sensitivity. Funding Statement: This study was supported by the Natural Science Foundation of Shandong Province (2009GQ10002037). Declaration of Interests: There are no conflicts of interest to declare. Ethics Approval Statement: Animals used in this study were treated in accordance with Shandong Provincial Hospital affiliated to Shandong University Animal Experimentation Ethic Committee (AEEC) guidelines, and were approved by the AEEC.

Acute angle closure glaucoma: management in acute attack setting

Introduction: Acute angle closure glaucoma is an emergency ophthalmic condition that occurs due to a sudden closure of the angle in the anterior chamber of the eye, causing an abrupt intraocular pressure (IOP) increase. The purpose of writing this case is to present clinical findings in acute glaucoma and the initial managements taken in reducing IOP.Case: A 45-year-old gentleman presented with 24-hour history of sudden severe left-sided headache associated with reduced vision on his left eye. Examination on the left eye revealed mixed conjunctival and ciliary injection, with visual acuity of 4/60 and raised intraocular pressure with the value of 40.2 on Schiotz tonometry. The anterior chamber was shallow, cornea was edematous, pupil was mid-dilated with diameter of 4 mm and unresponsive to light, iris crypt unclear, and hazed lens. The contralateral eye had a deep anterior chamber with normal pressure and a clear lens. He was treated initially by oral acetazolamide 250 mg two times a day, oral analgesic, a topical beta blocker 0,5% two times a day, and a topical steroid six times a day.Conclusion: A prompt and appropriate management in cases of acute glaucoma can prevent further complications and permanent blindness.

Quantitative rise in intraocular pressure in patients undergoing robotic surgery in steep Trendelenburg position: A prospective observational study.

Background and Aims:Raised intraocular pressure (IOP) is one of the known causes of anterior ischemic optic neuropathy. In the case of robotic urological-gynecological surgeries, patient is kept in steep Trendelenburg supine-lithotomy position. Aim of this study was to observe the quantitative rise in IOP in steep Trendelenburg position (>45°) in robotic-assisted prostatectomy and hysterectomy.Material and Methods:After institutional ethical clearance and written informed consent, 100 patients undergoing robotic surgeries in steep Trendelenburg position were recruited for the study. IOP was measured at different time intervals in steep Trendelenburg position using Schiotz tonometer: Post intubation (T1), post pneumoperitoneum (T2), post steep Trendelenburg (T3), and rest readings were taken 30 min apart. T9 was taken 10 min after patient is made supine and parallel to the ground. Mean arterial pressure (MAP), positive inspiratory pressure (PIP), and end-tidal carbon dioxide (EtCO2) values were recorded at different time points. Descriptive analysis, linear regression analysis, and Freidman's nonparametric tests were used to analyze the results.Results:Ninety-five patients were included for statistical analysis as five patients were excluded due to intraoperative interventions leading to alteration of results. Mean IOP at T1 was 19.181/18.462 mmHg in L/R eye. A gradual rise in IOP was observed with every time point while patient was in steep Trendelenburg position which reverts back to near normal values once the patient is changed to normal position 21.419/20.671: Left/right eye in mm of Hg. Uni and multiple regression analysis showed insignificant P value, thus no correlation between MAP, PIP, and EtCO2 with IOP.Conclusion:Steep Trendelenburg position for prolong duration leads to significant rise in intraocular pressure.