Bilateral Optic Neuropathy Associated with Acute Inhaled Marijuana Use: Case Report and Review of the Literature.

Marijuana is the most commonly used federally illegal drug in the United States. Acute marijuana use is associated with several cardiovascular and neuropsychological adverse effects. Ocular complications of marijuana abuse are very rare. Herein, we present the first report of bilateral optic neuropathy following smoking marijuana. A 28-year-old man presented to the emergency room with sudden onset of bilateral blurring of the inferior visual field 8 h after smoking marijuana. His best-corrected visual acuity was 20/30 in the right eye and 20/20 in the left eye. Fundus examination revealed blurring of the optic disc margins in both eyes and a splinter haemorrhage in the right eye. Bilateral inferior visual field defects were detected with greater severity on the right side. Optical coherence tomography confirmed the diagnosis of bilateral optic neuropathy. A urine drug screen test was positive for tetrahydrocannabinol, which is the primary active ingredient in cannabinoids. The rest of the neurological examination and imaging were normal. The patient was treated with intravenous corticosteroids and an anti-platelet drug. His vision recovered to 20/20 in both eyes, with complete resolution of the field defect over a follow-up of 6 months. Optic neuropathy following marijuana abuse is unusual. The results of our report emphasise the need for awareness of marijuana-associated optic neuropathy as part of ocular adverse effects of marijuana intoxication.

Uric acid and glaucoma: a systematic review and meta-analysis.

Background: Glaucoma, the leading cause of irreversible blindness, is a common disorder that contributes to gradual optic nerve degeneration. The beneficial impacts of uric acid (UA) have been reported in some neurodegenerative conditions such as Parkinson's disease, Alzheimer's disease, and amyotrophic lateral sclerosis. But the results of current studies about the association between serum UA level and glaucoma are conflicting. The present meta-analysis was conducted to provide a better understanding of the association between serum UA level and glaucoma. Methods: We searched the databases of PubMed, Scopus, Web of Science, and Google Scholar systematically until November 20, 2022 to identify case-control studies, comparing the serum UA concentrations of the patients with glaucoma and controls. The mean ± standard division difference was used to assess the difference in serum UA concentrations between the glaucoma patients and controls. Results: Six studies involving 1,221 glaucoma patients and 1,342 control group were included in the present meta-analysis. This meta-analysis using a random effect model indicated that the mean UA level in glaucoma patients was 0.13 (I2 = 91.92%, 95% CI = -0.42 to 0.68) higher than the controls; however, it was not statistically significant. Conclusions: Our findings provide evidence that glaucoma patients have a higher serum UA level compared to the controls, but this difference is not statistically significant. Prospective studies are needed to determine the possible association between increased UA and glaucoma pathogenesis. Systematic review registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022364055, identifier: CRD42022364055.

Comparison of visual outcomes, keratometric parameters and biomechanical profiles between deep anterior lamellar keratoplasty with big-bubble technique vs. Melles technique for keratoconus: a retrospective study.

OBJECTIVE: Comparing results of two different DALK surgery techniques (big bubble vs. Melles) in patients with advanced keratoconus. DESIGN: a retrospective comparative clinical study. PARTICIPANTS: This study conducted on 72 eyes of 72 participants. INTRODUCTION: This study designed to compare the results of two different DALK surgery techniques (big bubble vs. Melles) in patients with advanced keratoconus. METHOD: Thirty-seven eyes were treated using the big bubble DALK method, while 35 eyes were treated using the Melles approach. Uncorrected visual acuity (UCVA), best corrected spectacle visual acuity (BCSVA), manifest refraction, keratometric characteristics, contrast sensitivity, corneal aberrations, corneal biomechanical characteristics, and endothelial cell profile are the outcome measurements. RESULTS: Mean UCVA in big bubble group was 0.61 ± 25 LogMAR and in Melles group was 0.89 ± 0.41 LogMAR (p-value 0.043). Mean BCSVA in big bubble group (0.18 ± 0.12 Log MAR) was significantly better than Melles group (0.35 ± 0.16 Log MAR). Mean of sphere and cylinder refraction showed no significant difference between two groups. Comparing the endothelial cell profile, corneal aberrations, corneal biomechanical properties and keratometry had no significantdifferences. Contrast sensitivity reported as modulation transfer function (MTF) showed higher values in big bubble group and differences with Melles group weresignificant. Results of point spread function (PSF) in big bubble group had superiority to Melles group with considerable statistical P value of 0.023. CONCLUSION: When opposed to the Melles approach, the big bubble technique generates a smooth interface with less stromal residue, which results in higher visual quality and contrast sensitivity.

The Diagnostic Value of Neutrophil to Lymphocyte Ratio as an Effective Biomarker for Eye Disorders: A Meta-Analysis.

The neutrophil to lymphocyte ratio (NLR) reflects a dynamic relationship between the innate (neutrophils) and adaptive (lymphocytes) cellular immune response. This systematic review and meta-analysis was conducted to critically evaluate the literature regarding the use of the NLR as a reliable means to detect several ocular disorders. Our study was registered with the PROSPERO (ID: CRD42022314850). Three databases, including PubMed, Embase, Scopus, and the Web of Science, were searched on September 9, 2022, with no restrictions on the article's language. Finally, 32 articles were recognized as eligible for our meta-analysis. We found that patients with eye diseases had significantly elevated levels of NLR in comparison to healthy controls (SMD =0.53, 95% CI =0.35-0.71, P < 0.001). In subgroup analysis, patients with keratoconus (SMD =0.69; 95% CI =0.33-1.05, P < 0.001), glaucoma (SMD =0.56, 95% CI =0.25-0.87, P < 0.001), pterygium (SMD =0.14; 95% CI =0.01-0.26, P < 0.001), and idiopathic epiretinal membrane (SMD =0.14; 95% CI =0.01-0.26, P < 0.001) had higher levels of NLR compared to healthy controls. However, NLR levels of patients with dry eye disease were similar to healthy controls (SMD =0.32, 95% CI = -0.49-1.13, P = 0.435). It can be said that NLR is a valuable marker of systemic inflammation, which is significantly increased in many eye disorders, suggesting that inflammation plays a key role in the pathophysiology of these diseases.

Optic Neuropathy following Botulinum Toxin Injection into the Medial Rectus Muscle for Diplopia.

Purpose: To report a case of optic neuropathy (ON) following botulinum toxin A (BTA) injection into the medial rectus muscle. Case Report: We describe a 37-year-old man with unilateral ON after a BTA injection into the left medial rectus for treatment of traumatic sixth nerve palsy. Oral prednisolone was prescribed for 14 days. After two weeks, his visual acuity returned to 20/20. Conclusion: Botulinum toxin-induced neuropathy is a rare and vision-threatening complication of BTA. In patients with recent injection of BTA who present with visual complaints, botulinum toxin-induced neuropathy should be considered.

The Role of Optical Coherence Tomography in Early Detection of Retinal Nerve Fiber Layer Damage in Pituitary Adenoma.

Background and objectives:This study aimed to evaluate the ability of optical coherence tomography (OCT) to differentiate eyes without obvious visual disturbances following pituitary adenomas (PAs) from normal eyes, in order to identify factors that could predict early diagnosis and timely treatment and prevent structural damage of visual pathway in patients with saddle area tumors. Material and methods:The present study was carried out between 2014-2018. Participants were divided into three groups: 23 subjects (44 eyes) in the PAs with visual field involvement (VFI) group, 10 (20 eyes) in the PAs with normal visual field (NVF) group and 22 subjects (44 eyes) in the control group. All patients received diagnostic magnetic resonance imaging (MRI), automated perimetry, visual acuity, OCT and ophthalmological assessments. Also, the degree of visual field (VF) deficit and thickness of peripapillary retinal nerve fiber layer (pRNFL) were measured by OCT and then considered for statistical analysis as predictors of early diagnostic visual involvement in the PAs. Results:All patients in the NVF and control groups (a total of 64 eyes) had normal VF. In the VFI group there were 16 eyes with complete hemianopia. Bitemporal hemianopia occurred in 20 eyes and eight eyes with concentric VF narrowing. Assessment of pRNFL thickness with OCT demonstrated the average and all quadrants of pRNFL thickness in the VFI group were significantly thinner than the pRNFL thickness in the other groups (P<0.001). The pRNFL thickness in the inferior and nasal quadrants and the average value in the NVF group were significantly thinner than the control group (P<0.05). Conclusion:If a patient has band atrophy, there is an irreversible damage and the main goal is to diagnose a nerve damage using OCT before band atrophy.

The relationship between personality dimensions with resiliency and sense of coherence with respect to the role of spiritual health in the patients' candidate for eye surgery.

Introduction: This research aimed to determine the relationship between personality dimensions with the rate of resiliency and internal cohesion regarding the intermediary role of spiritual health in candidate patients for eye surgery. Methods: The method used in this is of correlation type, and statistical population in this project included all eye patients chosen for eye surgery who were examined at technical eye clinics in Tehran. The statistical sample included 200 patients from the statistical population who were chosen through a targeted sampling method. The data collection tools were Conner and Davidson's tolerance questionnaire (2003), Maccary and Costa's personality questionnaire (1985), Antonowski's internal cohesion scale (1970), and Politzin and Elison's spiritual health questionnaire (1982). The research hypotheses were examined through regression analysis, Pearson's correlation, and path analysis. Results: The results showed that the calculated fit indices of the structural model of the research were correlated with the five dimensions of personality and internal cohesion of patients undergoing eye surgery with respect to the mediator role of spiritual health with 88% confidence. Investigation of path analysis coefficients showed a significant relationship between exogenous and intermediary variables on resiliency and internal cohesion (P value = 0.00). Conclusion: According to the results of the research, the spiritual health variable plays a significant mediating role for exogenous and endogenous variables in this model. Therefore, personality traits not only directly influence resilience and internal cohesion but also indirectly influence spiritual well-being.

Serosurvey of parvovirus B19 and cytomegalovirus infections among female university students in Shiraz, Southern Iran.

Infection with parvovirus B19 and cytomegalovirus (CMV) during pregnancy might lead to fetal infection, resulting in congenital abnormalities. This study aimed to investigate the frequency of IgM and IgG antibodies against parvovirus B19 and CMV in female university students in Shiraz, in Fars province, Southern Iran. In this cross-sectional study, 370 female university students were included. Blood samples were collected from each participant and tested for anti-parvovirus B19 and CMV IgG and IgM antibodies, using commercial ELISA kits. The mean age of the participants was 24 (±7)years. Out of 370 participants, 327 (88.4%) and 9 (2.4%) were positive for IgG and IgM antibodies against CMV. Moreover, 211 (57.0%) and 4 (1.1%) of the participants were respectively positive for IgG and IgM antibodies against parvovirus B19. The difference in CMV or parvovirus B19 seropositivity between different age groups was not statistically significant (P>0.05). The findings of our study showed that more than 50% of the female university students are seropositive to CMV and parvovirus B19 infections. It highlights the importance of health education and also the laboratory screening of females at childbearing age to reduce the risk of congenital infections resulting from these viral infections.

Endocapsular hematoma as an uncommon early postoperative complication of phacoemulsification with intraocular lens implantation surgery.

Herein we describe a 55-year-old woman presented with a chief complaint of visual loss in the right eye of 3 days duration. The patient underwent uncomplicated phacoemulsification cataract surgery on the right eye 1 week ago. Slit lamp examination revealed accumulation of blood in the capsular bag behind the intraocular lens with blood level. The patient was diagnosed as endocapsular hematoma. Neodymium-doped: yttrium-aluminum-garnet laser posterior capsulotomy was performed. The patient's vision improved completely.

Non-medial infectious orbital cellulitis: etiology, causative organisms, radiologic findings, management and complications.

BACKGROUND: Orbital cellulitis is an ophthalmic emergency, which is associated with vision-threatening adverse effects. The purpose of this study is investigating etiology, radiologic findings, management and complications of patients with non-medial orbital cellulitis. METHOD: A retrospective medical record and radiologic file review of patients with infectious orbital cellulitis was performed to detect all patients with non-medial orbital cellulitis who referred to Khalili hospital from 2016 to 2019. Age, sex, origin of infection, size of collection or abscess, medical or surgical management, microbiology, first and final best-corrected visual acuity, duration of admission, and complications was recorded. Patients divided into two groups; medical management and surgical management groups and all of data compared between in this groups. RESULTS: Of ninety-six patients with infectious orbital cellulitis, 23 cases (14 male, 9 female) were included. Five patients (21.7%) were managed medically and 18 patients (78.3%) were managed surgically. Patients' age range was 5-70 years old. Most common location for non-medial cellulitis was superior space (66.7% in surgical and 40% in medical group; p = 0.511). In 13 cases of surgical group (72.3%) were detected microorganisms. The mean ± SD of collection volume in medical group were 476.5 ± 290.93 mm3 and 2572.94 ± 1075.75 mm3 in surgical group (p < 0.001). Ten patients in surgical group had compressive optic neuropathy. The mean ± SD of collection volume was 3204.97 ± 879.88 mm3 in patient with compressive optic neuropathy and 1280.43 ± 880.68 mm3 in patient without compressive optic neuropathy (P < 0.001). One case complicated by subdural empyema and another case progressed to necrotizing fasciitis. CONCLUSION: Non-medial orbital cellulitis is an uncommon but sight-threatening and life-threatening condition. Timely diagnosis and accurate management reduce morbidity and mortality. Combined surgery for patients with superior or supra-temporal and large non-medial abscess is recommended.

Corneal Collagen Cross-Linking Using Epithelium Disruptor Instrument in Progressive Keratoconus.

PURPOSE: To compare the effects of accelerated corneal collagen cross-linking (CXL) in progressive keratoconus (KCN) patients via epithelium removal and transepithelial techniques, using Daya Disruptor (Duckworth and Kent, Hertfordshire, UK). METHODS: This study is a double-blinded, randomized clinical trial. Patients with documented bilateral progressive KCN were randomized into two groups: one eye underwent epithelium removal (Group 1), and the fellow eye underwent epithelium disruption (Group 2). The primary outcomes were best corrected visual acuity (BCVA) and uncorrected visual acuity (UCVA), Scheimpflug-extracted keratometric indices, and anterior segment-optical coherence tomography-derived epithelial thickness profiles. These parameters were evaluated before and 12 months after CXL. RESULTS: Sixty-four eyes from 34 patients with progressive KCN (34 eyes in the epithelium-removal group and 30 eyes in the epithelium-disruption group) were included. The mean ± standard deviation (SD) of age was 23.4 ± 3.8 years in the epithelium-removal group and 23.2 ± 3.5 years in the epithelium-disruption group. The mean ± SD of the preoperative spherical equivalent (SE), front maximum keratometry (K-max), back K-max, thickness of thinnest point, and corneal apex thickness were - 2.9 ± 3.0 diopter (D) and - 3.7 ± 3.1 D (P = 0.183), 53.8 ± 5.15 D and 54.4 ± 5.53 D (P = 0.653), -6.63 ± 2.40 D and - 6.68 ± 2.48 D (P = 0.131), 459.2 ± 37.4 µm and 460.8 ± 32.7 µm (P = 0.708), 470.5 ± 37.7 µm and 469.7 ± 33.1 µm (P = 0.679), and 55.4 ± 4.97 µm and 54.6 ± 7.16 µm (P = 0.767) in the epithelium-removal and epithelium-disruption groups, respectively. The mean ± SD changes of the UCVA and BCVA 12 months after CXL were - 0.1 ± 0.11 and - 0.02 ± 0.18 and - 0.04 ± 0.12 and - 0.02 ± 0.14 in the epithelium-removal and epithelium-disruption groups, respectively. No statistically significant improvement was observed in the UCVA and BCVA between the two groups (P = 0.868 and P = 0.937, respectively). The mean ± SD changes of the SE, superior epithelial thickness, corneal apex thickness, and thickness of thinnest point 12 months after CXL were - 0.21 ± 1.1 D and + 0.32 ± 1.6 D (P = 0.0001), -0.08 ± 0.26 µm and + 0.03 ± 0.33 µm (P = 0.028), -23 ± 11 µm and - 2 ± 6 µm (P = 0.0001), and - 25 ± 8 µm and - 3 ± 7 µm (P = 0.0001) in the epithelium-removal and epithelium-disruption groups, respectively. CONCLUSIONS: This study showed that the epithelium-disruption CXL using Daya has a similar potential for halting KCN progression as the epithelium-removal CXL. However, regarding the 12-month changes, the epithelium-disruption CXL is superior to the epithelium-removal CXL in the SE and corneal pachymetry.

Acute bilateral granulomatous anterior uveitis as an extra-hepatic manifestation of hepatitis A virus (HAV) infection: a case report.

Anterior uveitis (AU) is the most common form of uveitis. The differential diagnosis of AU is broad, ranging from infectious etiologies to autoimmune causes. However, approximately half remain idiopathic. Infections are the vision-threatening causes of AU which should be ruled out by history taking and detailed physical examination combined with guided work up. We report a rare case of bilateral granulomatous AU following hepatitis A virus (HAV) infection in an immunocompetent patient. A 35-year-old male presented to our center with a chief complaint of pain and redness in both eyes 3 days prior to the presentation. The patient's medical and drug history was unremarkable. He had a history of river water consumption 20 days prior to presentation. The patient was diagnosed with acute bilateral granulomatous AU. All routine work up to investigate the etiology of the disease was unremarkable, except for the serology of acute HAV infection, which was positive. The patient was managed with the topical steroid and cycloplegic for 2 weeks with no recurrence at one-year follow up. Extra-hepatic complications of HAV were reported in previous studies including arthritis, urticaria, myocarditis, nephritis, and myositis. The mechanism of extra-hepatic complication of hepatitis A is unknown; however, immune-complex deposition is most likely the etiological cause. Our report represents a rare case of sudden onset with limited duration granulomatous AU as a presenting manifestation of HAV infection. Previous studies do not provide a direct evidence of granulomatous AU associated with the HAV infection.

Fourier Analysis of Keratometric Data in Epithelium Removal versus Epithelial Disruption Corneal Cross-linking.

PURPOSE: To compare epithelium-removal and epithelium-disruption corneal crosslinking (CXL) methods in Fourier analysis of keratometric data and clinical outcomes. METHODS: In this double masked randomized clinical trial, each eye of 34 patients with bilateral keratoconus was randomly allocated to either the epithelium-removal or epithelium-disruption CXL treatment groups. Ocular examination, refraction, uncorrected and best spectacle-corrected visual acuity (UCVA and BSCVA, respectively) measurements, and Pentacam imaging (keratometry, pachymetry, and Fourier analysis) were performed at baseline and at six-month follow-up period. RESULTS: Patients' mean age was 23.3 ± 3.6 years. The preoperative thickness of the thinnest point was 459.20 ± 37.40 µm and 455.80 ± 32.70 µm in the epithelium-removal and epithelial-disruption CXL groups, respectively (P > 0.05). The corresponding figures were 433.50 ± 33.50 µm and 451.90 ± 39.70 µm, respectively, six months after the treatment (P = 0.0001). Irregularity component of the fourier analysis was 0.030 ± 0.016 µm in the epithelium-removal group and 0.028 ± 0.011 µm in the epithelium-disruption group preoperatively (P > 0.05). This measurement was 0.031 ± 0.016 µm and 0.024 ± 0.009 µm, respectively at month 6 (P = 0.04). The epithelium-disruption CXL group had better results in terms of the thickness of the thinnest point and the irregularity component as compared to the epithelium-removal group. The two study groups were comparable in spherical equivalent, mean keratometry, UCVA, BSCVA, or other Fourier analysis components (spherical R min, spherical eccentricity, central, peripheral regular astigmatism, and maximum decentration) (P > 0.05). CONCLUSION: This study shows that epithelium-disruption CXL is superior to epithelium-removal CXL regarding the short-term changes in pachymetry and corneal irregularity. Other evaluated parameters were comparable between the two techniques.

Comparison of the Effectiveness of Onion Extract, Topical Steroid, and Petrolatum Emollient in Cosmetic Appearance of Upper Blepharoplasty Scar.

PURPOSE: To compare the effectiveness of onion extract, topical steroid, and petrolatum emollient in the prevention of scars in cases who underwent bilateral upper eyelid blepharoplasty. METHODS: A prospective, interventional, comparative, double-blinded case series was designed on cases who underwent upper lid blepharoplasty. After suture removal (1 week following the surgery), the eyelids of participants were randomly allocated into the three groups: The first group used onion extract on the right eyelids (n = 18), and the second group used topical steroid on the right eyelids (n = 19). In the third group, the control group, petrolatum emollient was used on the left eyelids (n = 37) of the first and second group's cases. They used drugs for 2 months and were evaluated by the Manchester Scar Scale (MSS) objectively by two graders who were blinded to the type of medication. MSS evaluates five different characteristics of the scar in addition to the Visual Analog Scale (VAS). These characteristics include color, distortion, contour, texture, and transparency. VAS scores the overall scar appearance which ranged among 0-10. The sum of the scores for the five different parameters, and VAS was calculated, analyzed, and compared among the groups. RESULTS: A total of 37 cases (74 eyelids) who underwent bilateral upper blepharoplasty were included. The mean ± standard deviation (SD) of age was 51.94 ± 9.26 years, 49.40 ± 9.37 years, and 47.00 ± 9.06 years in the onion extract, topical steroid, and petrolatum emollient groups, respectively (P = 0.275). There were no statistically significant differences in the mean ± SD of the sum of the MSS scores among the three groups (P = 0.924) or between the onion extract and topical steroid groups (P = 0.951). Furthermore, the color, distortion, contour, texture, transparency, and VAS scores were not statistically significantly different among the three groups or between the onion extract and topical steroid groups (P > 0.05). CONCLUSION: There were no significant differences among these three groups of drugs regarding the appearance of the upper blepharoplasty scar.

Endogenous Candida Endophthalmitis as a Rare Complication of Trans-Urethral Lithotripsy in a Healthy Woman: A Case Report

Endogenous endophthalmitis is a serious sight-threatening ocular emergency that usually occurs in patients with serious underlying risk factors. In this report, we describe a case of endogenous Candida endophthalmitis following trans-urethral lithotripsy in an immunocompetent woman. In our case, the retinal lesion regressed completely and vision was restored. We discuss diagnostic procedures and management strategies in this article.

Corneal wasp sting: A case report and review of literature.

PURPOSE: To report severe immunologic and toxic reaction due to corneal wasp sting that may cause catastrophic sight-threatening outcomes. METHODS: A 45-year-old man referred to the emergency room with corneal wasp sting of Vespa Orientalis. The authors review previous Medline literature about this topic. RESULTS: In our case, the response to frequent topical corticosteroid was dramatic, and at the seventh day after injury, all inflammatory responses in the anterior segment of the eye had been resolved. CONCLUSION: Corneal wasp injury with Vespa Orientalis can cause severe inflammation of the cornea and the anterior segment. Topical corticosteroids are the mainstay of treatment.

Unilateral endogenous Candida endophthalmitis after extracorporeal shock wave lithotripsy for a renal stone in an immunocompetent woman: a case report.

PURPOSE: To report a case of endogenous Candida endophthalmitis that may cause catastrophic sight-threatening outcomes, after extracorporeal shock wave lithotripsy (ESWL) in a healthy woman. CASE PRESENTATION: A 32-year-old woman presented to the ophthalmology clinic with the symptom of blurred vision and floater in her right eye. She underwent ESWL for renal stone 1 week prior to her presentation. Fundus examination showed an elevated white lesion in para-fovea with fluffy border. Smear of diagnostic vitreous sampling showed pseudo-hypha and budding yeast. Systemic and immunologic and infectious workups were unremarkable. In our case, response to intravitreal and intravenous injection of amphotericin-B and oral fluconazole was dramatic. Six weeks after starting the treatment, infiltrative lesion completely disappeared. The authors review previous MEDLINE literature about this topic. CONCLUSION: Endogenous Candida endophthalmitis following renal stone lithotripsy is a serious and rare intraocular infection that may happen in healthy individuals without any risk factors.

Hemodynamic effect of intravenous lidocaine during aortic cannulation in cardiac surgery.

BACKGROUND: Dissection of aorta is a rare, but fatal complication of aortic cannulation in cardiac surgery can be caused by the sudden rise in blood pressure and hemodynamic variations. METHODS: In this study, 90 patients aged 18 years or older undergoing cardiac surgery were divided into two equal groups. Under similar conditions, trial group received 1.5 mg/kg of lidocaine for 90 s before cannulation and control group received normal saline. Hemodynamic parameters of patients including systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), heart rate (HR), and central venous pressure before cannulation and 1, 3, and 5 min after cannulation were recorded in a form. Consumed nitroglycerin (TNG) rate was also measured and recorded. RESULTS: In the lidocaine group, compared with the placebo group, mean SBP, DBP, and MAP significantly reduced after cannulation (P < 0.05). During the follow-up period, mean HR (P = 0.649) and TNG usage (P = 0.527) were similar in two groups. CONCLUSION: Intravenous lidocaine, 1.5 mg/kg, 90 s before cannulation leads to a reduction in SBP, DBP, and MAP, up to 5 min after cannulation, so it can decrease risk of aortic dissection.

The effect of nitroglycerin as an adjuvant to lidocaine in intravenous regional anesthesia.

PURPOSE: The disadvantages of intravenous regional anesthesia (IVRA) include slow onset, poor muscle relaxation, tourniquet pain, and rapid onset of pain after tourniquet deflation. In this randomized, double-blind study, we evaluated the effect of nitroglycerin (NTG) in quality improvement when added to lidocaine in IVRA. METHODS: Forty-six patients (20-50 yrs), were randomly allocated in two equal groups. Under identical condition, the control group received a total dose of 3 mg/kg of lidocaine 1% diluted with saline, and the study group received an additional 200 microg NTG. Vital signs and tourniquet pain, based on visual analog scale (VAS) score were measured and recorded before and 5, 10, 15, 20, and 30 min after anesthetic solution administration. The onset times of sensory and motor block were measured and recorded in all patients. After the tourniquet deflation, at 30 min and 2, 4, 6, 12 and 24 h, VAS score, time to first analgesic requirement, total analgesic consumption in the first 24 h after operation, and side effects were noted. RESULTS: The sensory and motor block onset time were shortened in study group (2.61 vs. 5.09 and 4.22 vs. 7.04 min, respectively) (p < 0.05). The recovery time of sensory and motor block and onset of tourniquet pain were also prolonged (7.26 vs. 3.43, 9.70 vs. 3.74 and 25 vs. 16.65 min., respectively) (p < 0.05). Analgesia time after tourniquet deflation was prolonged and tourniquet pain intensity was lowered in study group (p < 0.05). Intraoperative fentanyl and meperedine requirement during first postoperative day and pain intensity at 4, 6, 12 and 24 hr postoperatively were lower in the study group (p < 0.05). There were no significant side effects. CONCLUSION: The NTG adding to lidocaine in intravenous regional anesthesia shortens onset times of sensory and motor block and decreases the tourniquet and postoperative pain, without any side effect.