Subconjunctival Group Research Articles

Intrastromal versus subconjunctival injection of mesenchymal stem/stromal cells for promoting corneal repair

PurposeDifferent approaches to delivery of mesenchymal stem/stromal cells (MSCs) for ameliorating corneal injuries have been investigated. This study was aimed to compare the efficacy of intrastromal and subconjunctival injection of human bone marrow-derived MSCs (hBM-MSCs) in a corneal epithelial injury model. MethodsTwenty-four C57BL/6J mice underwent total corneal and limbal epithelial debridement. Then, the mice were divided into three different groups: (1) intrastromal hBM-MSCs injection, (2) subconjunctival hBM-MSCs injection, and (3) injection of frozen medium as a control. Mice were monitored by slit lamp and underwent anterior segment optical coherence tomography (ASOCT). Following euthanasia, the corneas were further evaluated by histology and immunostaining. ResultshBM-MSC injection successfully healed epithelial defects regardless of the delivery route (P < 0.001). However, intrastromal injection was superior to subconjunctival injection in reducing defect area (P = 0.001). Intrastromal injection of hBM-MSCs also significantly reduced corneal opacity and neovascularization and improved ASOCT parameters compared to subconjunctival injection or no treatment (P < 0.001, P = 0.003, and P < 0.001, respectively). Although both of the treatment groups were positive for CK12 and had reduced levels of MUC5AC compared to the control, CK12 staining was stronger in the intrastromal group compared to the subconjunctival group. Also, persistency of MSCs was confirmed by in vivo (up to 2 weeks) and in vitro assessments (up to 4 weeks). ConclusionsAlthough the injection of hBM-MSC using both intrastromal and subconjunctival methods improve wound healing and reduce neovascularization and opacity, the intrastromal approach is superior in terms of corneal healing.

Sub-tenon Versus Sub-conjunctiva Anaesthesia for Intraocular Surgery.

To compare the pain relief achieved using sub-Tenon anesthesia with that of sub-conjunctival anesthesia technique in intraocular surgery at the Guinness Eye Centre Onitsha Nigeria. Consecutive adult patients who had intraocular surgery under local anesthesia were randomized into having sub-Tenon (3 mL) or sub-conjunctival (0.5 mL) injections using xylocaine ± adrenaline. The manual suture-less surgery technique was used for cataract surgery alone and cataract surgery with pterygium excision; the extra-capsular cataract extraction technique was adopted for combined trabeculectomy and cataract surgery. Surgery duration was recorded. Patient's pain perception graded as none, mild, moderate or severe. 100 patients made up 51 (51.0%) males and 49 (49.0%) females, age range was 31-88 years, median - 68 years, participated. Sub-Tenon anesthetic technique was used in 52 (52.0%) and sub-conjunctival in 48 (48.0%) participants. Seventy-eight (78.0%) patients had cataract surgery; 10 (10.0%) had trabeculectomy; 7 (7.0%) had combined trabeculectomy and cataract surgery and 5 (5.0%) had pterygium excision with cataract surgery. The mean surgery duration in the sub-Tenon anesthesia group was 31.8 ± 8.5 minutes and 30.2 ± 9.8 minutes in the sub-conjunctival group (P > 0.05). Fifty (96.2%) patients in the sub-Tenon group and 38 (79.2%) in the sub-conjunctival group experienced mild or no pains; 2 (4.2%) patients in the sub-Tenon group and 10 (20.8%) in the sub-conjunctival group experienced moderate to severe pains (P < 0.05). Both sub-conjunctival and sub-Tenon anesthetic achieved effective analgesia in intraocular surgery. But sub-Tenon anesthesia is significantly associated with lower incidence of severe pains.

Effect of Topical Versus Sub-conjunctival Anaesthesia during Administration of Intravitreal Bevacizumab Injection

Purpose: To compare the anesthetic effect of topical proparacaine hydrochloride 0.5% with sub-conjunctival lidocaine 2% for intravitreal injection of Bevacizumab.&#x0D; Study Design: Quasi experimental study.&#x0D; Place and Duration of Study: Department of Ophthalmology Fauji Foundation Hospital, Rawalpindi, from July 2017 to January 2018.&#x0D; Methods: Sixty 60 patients who needed intravitreal Bevacizumab were included in the study after approval from the ethical review board. Exclusion criteria were patients with conditions that could affect pain sensation, acute ocular inflammation, history of intravitreal injection, using systemic analgesic/sedatives, uncooperative patients and unable to understand the pain scale. Written informed consent was taken. Name, age, gender, diagnosis, previous intravitreal injection, hospital registration number, address and contact numbers were noted. Patients were briefed about the visual analogue scale. Patients were divided into two groups. Group A received proparacaine drops and group B was given subconjunctival lidocaine injections before intravitreal bevacizumab.&#x0D; Results: The mean age of patients in this study was 60.38 ± 10.55 years. There were 03 (5.0%) males and 57 (95.0%) females. Majority of the patients (30%) presented with choroidal neovascularization followed by diabetic maculopathy, vitreous hemorrhage, central retinal vein occlusion and proliferative diabetic retinopathy. Mean pain score among both the groups was 3.67 ± 1.97 (topical group) and 1.70 ± 1.51 (sub-conjunctival group) respectively which was statistically significant (p-value 0.000). Among age, diabetes, duration of diabetes and hypertension, only hypertension had moderate correlation with the pain score (correlation coefficient = 0.316, p values = 0.017).&#x0D; Conclusion: Sub-conjunctival anaesthesia results in less pain during intravitreal drug administration as compared to the topical anaesthesia.&#x0D; Key Words: Intravitreal injections, Bevacizumab, Intravitreal Anti-VEGF, Anesthesia.

Effects of VEGF Inhibitor Conbercept on Corneal Neovascularization Following Penetrating Keratoplasty in Rabbit Model.

PurposeTo evaluate the effects of the vascular endothelial growth factor inhibitor conbercept (KH902) on corneal neovascularization and wound healing following penetrating keratoplasty in rabbits.MethodsConbercept was administered to New Zealand white rabbits through topical and subconjunctival routes. Corneal neovascularization and wound healing were examined by slit-lamp photography and histological analyses. The expressions of vascular endothelial growth factor inhibitor, α-smooth muscle actin, and keratocan in the corneal grafts were measured by real-time quantitative polymerase chain reaction (RT-qPCR).ResultsThe anterior segment photographs demonstrated that corneal neovascularization started in the 2nd week. In the 4th week, histologically, the superficial corneal stroma layer showed disordered arrangement, and there were large numbers of dense inflammatory cells and blood vessels in the stroma layer. Vascular endothelial growth factor in the experimental groups was significantly decreased at all time points compared with the control group (both P = 0.001). Expression of α-smooth muscle actin in corneal grafts demonstrated an increase in time even it was lower in experimental groups, but the difference was not statistically significant (P equaled to 0.507 and 0.723, respectively). There were no significant differences with the expression of keratocan in all groups except that it significantly declined at the 4th week as to the second week in all groups and P values were 0.022, 0.020 and 0.014 in control (C), topical (E1), and subconjunctival (E2) group, respectively.ConclusionThe study found that conbercept inhibited the formation of corneal neovascularization without affecting keratocan-mediated corneal wound healing and there were no significant differences between topical administration of different doses of conbercept on the rabbit corneal neovascularization after penetrating keratoplasty in this study.

Preliminary study of a controllable device for subtenon drug infusion in a rabbit model.

Conventional methods to treat intraocular diseases are invasive or associated with adverse effects. A minimally invasive means of sustained-release drug delivery to the vitreous is required. This study evaluated a novel device for subtenon drug delivery to the vitreous, relative to a single subconjunctival injection. Sixty adult New Zealand White rabbits were randomly assigned to receive demethylvancomycin (DMV) by continuous subtenon delivery with the flow rate of 0.1ml/hr for 24hr, or as a single 0.3ml subconjunctival injection in the right eyes. Rabbits were killed in subgroups of six at 1, 3, 6, 12 and 24hr. The DMV concentration of the vitreous humour of the right eye was analysed by high-performance liquid chromatography. Overall, the vitreous DMV concentration of the subtenon group was significantly higher than that of the subconjunctival group (F=25.928, p=0.001). The DMV concentration of the subtenon group was also significantly higher than that of the subconjunctival group at 3, 6, 12 and 24hr (t=2.457, 5.064, 3.085, 4.207; p=0.04, 0.01, 0.018, 0.004, respectively). In the subtenon group, the DMV concentration reached maximum (2.41±0.67μg/ml) at 6hr, and at 24hr was 2.37±1.23μg/ml. In the subconjunctival group, the DMV concentration reached maximum (0.48±0.27μg/ml) at 1hr and declined to 0.09±0.05μg/ml at 24hr. Subtenon application with this novel minimally invasive design is an effective method for delivering an appropriate drug to the vitreous in a sustained and controllable amount.

One-Year Outcomes of the SAVE Study: Sirolimus as a Therapeutic Approach for UVEitis.

To determine the efficacy and safety of repeated intravitreal and subconjunctival administrations of sirolimus in patients with noninfectious uveitis at 1 year in the Sirolimus as a Therapeutic Approach UVEitis (SAVE) Study. Open-label, prospective, and randomized interventional clinical trial in which 30 patients with noninfectious intermediate, posterior, or panuveitis were randomized 1:1 to receive sirolimus 352-μg intravitreal or 1320-μg subconjunctival. Sirolimus was administered at days 0, 60, and 120. At month 6, all subjects were allowed to receive sirolimus at intervals greater than or equal to 2 months and until month 12. Changes in vitreous haze (VH), visual acuity (VA), and retinal thickness at month 12 were compared with baseline. Of patients with active uveitis at baseline (n = 20), 70% showed greater than or equal to 2 steps reduction of VH at month 12 (P < 0.05), 88% (n = 7) of patients with inactive uveitis at baseline showed either no change or reduction of VH to no haze, 36% (n = 10) of all patients (n = 28) gained greater than or equal to one line of VA, 21% (n = 6) lost greater than or equal to 1 line, and 43% (n = 12) showed no change. At the end of 1 year, no statistical differences in efficacy were found between intravitreal and subconjunctival groups. No serious adverse events were determined to be secondary to sirolimus. Repeated subconjunctival/intravitreal injections of sirolimus appear to be tolerated by patients with noninfectious uveitis over 12 months. Results from the index study suggest that sirolimus may provide benefits to patients with uveitis. Both intravitreal and subconjunctival routes demonstrate similar bioactivity/efficacy. The intravitreal route, however, was better tolerated. The SAVE Study illustrates for the first time the application of local formulations of sirolimus in non-infectious intermediate, posterior, and pan-uveitis. Subconjunctival/Intravitreal sirolimus may help to control inflammation while offering better tolerability/safety profiles than systemic therapies, including immunosuppressants and corticosteroids.

Direct Comparison of Administration Routes for AAV8-mediated Ocular Gene Therapy

Purpose: We recently demonstrated that direct subretinal (SR) injection of adeno-associated virus (AAV) type 8 (AAV8) into photoreceptor cells and retinal pigment epithelium (RPE) is a highly efficient model of gene delivery. The current study compared transduction efficiency and expression patterns associated with various routes of vector administration.Method: The efficacy of intravitreal (VT), SR and subconjunctival (SC) injections for delivery of AAV8-derived vectors, i.e. those expressing luciferase (Luc) and enhanced green fluorescent protein (GFP) – AAV8/Luc and AAV8/GFP, respectively – were compared in an animal (mouse) model (n = 8 mice/group). Transduction efficiency and expression patterns were examined at post-injection weeks 1 and 2, and months 1, 3, 6 and 12 via in vivo imaging.Results: One year after AAV injection, AAV8/Luc-treated mice exhibited stable and sustained high expression of vector in the VT and SR groups, but not in the SC group (VT:SR:SC = 3,218:2,923:115; 1 × 105 photons/s). Histological analysis showed that GFP expression was observed in the inner retina of VT group mice, and in photoreceptor cells and RPE of SR group mice, whereas no GFP expression was noted in the SC group. Electroretinography (ERG) revealed adverse effects following SR delivery.Conclusions: Results suggest that both SR and VT injections of AAV8 vectors are useful routes for administering ocular gene therapy, and stress the importance of selecting an appropriate administration route, i.e. one that targets specific cells, for treating ocular disorders.

Superior subconjunctival anesthesia versus retrobulbar anesthesia for manual small-incision cataract surgery in a residency training program: a randomized controlled trial

PurposeTo evaluate the effectiveness of subconjunctival anesthesia as compared to retrobulbar anesthesia for pain control during manual small-incision cataract surgery (MSICS) performed by third-year residents.DesignA randomized, controlled trial.Patients and methodsA total of 150 patients undergoing routine cataract surgery were randomly assigned to receive either subconjunctival anesthesia (group 1, n = 75) or retrobulbar anesthesia (group 2, n = 75). Third-year residents performed MSICS using the modified Blumenthal technique. Subconjunctival anesthesia was administered by injecting 2% xylocaine with adrenalin into the superior conjunctiva, and retrobulbar anesthesia by injecting 2 mL of 2% xylocaine with adrenalin into the retrobulbar space. We studied the following variables: intraoperative pain score rated on a 100-point visual analog scale (VAS), operative time, and injection and operative complications.ResultsA mean age of 69 vs 70 years, an operative time of 47.1 (SD, 9.9) min vs 47.7 (10.9) min, and a median (interquartile range) pain score of 40 (range, 20–70) vs 40 (range, 20–50) were observed in the subconjunctival and the retrobulbar groups, respectively. The injection complication of subconjunctival hemorrhage was significantly higher in the subconjunctival group (25.3%) compared to the retrobulbar group (1.3%). The operative complication rate between groups was not different (P > 0.05).ConclusionBoth, superior subconjunctival anesthesia and retrobulbar anesthesia were effective during MSICS when used in a residency training program.

Retrobulbar versus subconjunctival anesthesia for cataract surgery

To compare the effectiveness, in terms of pain relief and akinesia of retrobulbar and subconjunctival an aesthesia during cataract surgery and also to compare the degree of postoperative ptosis associated with each technique. Consecutive adult patients undergoing cataract surgery between March and June 2008 at the Guinness Eye Center Onitsha, were randomized into retrobulbar and subconjunctival an aesthesia by simple random sampling. Patients' subjective perception of pain was graded into none, mild, moderate and severe; eyeball movement during surgery was graded into none, slight, moderate excessive. Two weeks after surgery, the palpebral fissure width was measured with the metre rule to determine the degree of post-operative ptosis. Of the 90 patients studied, 55 (61.1%) patients had subconjunctival an anesthesia while 35(38.9%) had retrobulbar injection. In the retrobulbar injection group 25 (71.4%) patients had none or mild pains compared to 44 (80.0%) in the subconjunctival injection group; while 10 (28.6%) patients in the retrobulbar group experienced moderate to severe pains, 11 (20%) patients in the subconjunctival group had moderate pains and none experienced severe pains. But the difference in the degree of pain perception between the 2 groups is not statistically significant (χ2 = 0.01; df - 1; P>0.05 ). In the retrobulbar injection group, there was none or slight movement of the globe in 30 (85.7%) patients compared to 49 (89.1%) patients in the subconjunctival group. While 5 (14.3%) patients in the retrobulbar injection group had moderate globe movement, no patient in this group had excessive movement. In the subconjunctival injection group, 5 (9.1%) patients had moderate movement and 1 (1.8%) patient had excessive eyeball movement. The difference in the movement of the eyeball between the retrobulbar and the subconjunctival injections group was not significant (χ2 = 0.004; df - 1; P>0.05 ). In the retrobulbar injection group, the palpebral fissure width was within ≥ 10mm in 18 (51.0%) patients compared with 29 (53.0%) patients in the subconjunctival group. This difference was not statistically significant (χ2 = 0.0006; df - 1; P>0.05 ). Both retrobulbar and subconjunctival an aesthetic techniques are effective and safe for cataract surgery although the pain experience may be slightly more for patients being operated upon under retrobulbar anaesthesia.

Comparision of the effects of subtenon’s and subconjunctival anesthesia on retroorbital hemodynamics

Abstract The aim of the study was to compare retroorbital blood flow hemodynamics between subconjunctival and sub-Tenon’s anesthesia. This was a prospective, blinded study and included 80 cases. Patients were monitored and treated in the First Ophthalmology Clinic, Ataturk Training and Research Hospital, Turkey. Sub-Tenon’s anesthesia was performed in 42 cases, and subconjunctival anesthesia was performed in 38 cases. Color Doppler imaging to measure ocular blood flow parameters was performed preoperatively and 21 days after cataract operation in each case. Preoperative and postoperative values of resistivity and pulsatility indices in the ophthalmic, central retinal, and short posterior ciliary arteries were compared. Postoperative mean blood flow velocity measurements of ophthalmic artery were not statistically different between the subconjunctival anesthesia group and the sub-Tenon’s anesthesia group (49.63 ± 14.00 vs. 45.85 ± 13.41; P=0.389). Postoperative RI values were higher in the Subtenon’s anesthesia group than in the subconjunctival anesthesia group, but the difference between two groups was not statistically significant (0.81 ± 0.14 vs. 0.74 ± 0.08; P=0.079). The postoperative pulsatility index of the ophthalmic artery, RI of ophthalmic artery, pulsatility index of the central retinal artery, RI of the central retinal artery, and pulsatility index of the posterior ciliary arteries were not significantly different between the subconjunctival and sub-Tenon’s anesthesia groups. In conclusion, the study suggests that postoperative retroorbital blood flow hemodynamics are the same following sub-Tenon’s and subconjunctival anesthesia.

Comparative Study of Analgesic Effectiveness Using Three Different Anesthetic Techniques for Intravitreal Injection of Bevacizumab

To compare the analgesic effectiveness and aesthetic appearance associated with topical, subconjunctival, and peribulbar anesthesia for intravitreal bevacizumab injection. Sixty consecutive patients undergoing their first intravitreal bevacizumab injection were randomized to receive one of three forms of anesthesia: proxymetacaine eye drops, subconjunctival injection of 2% xylocaine, and peribulbar injection of 2% xylocaine. Pain associated with the intravitreal injection and with the entire procedure (including anesthesia administration) was recorded using a Visual Analog Scale 15 minutes after intravitreal injection. Anterior segment evaluation was performed 24 hours after injection to measure the number of clock hours of subconjunctival hemorrhage. Median injection-related pain score was significantly lower in the peribulbar group compared with the topical and subconjunctival groups (P < .05). Median entire procedure pain score was significantly higher in the peribulbar group compared with the topical and subconjunctival groups (P < .05). The median extent of subconjunctival hemorrhage was significantly lower in the topical group compared with the other groups (P < .05). Among the three anesthetic techniques, peribulbar anesthesia was associated with greater effectiveness in controlling injection-related pain but was least effective in controlling entire procedure pain. There was no significant difference in pain scores between the topical and subconjunctival groups, and topical anesthesia was associated with less subconjunctival hemorrhage.

Topical and subconjunctival bevacizumab in corneal neovascularization in keratoplasty patients

Abstract Purpose To report the clinical use of topical and subconjunctival bevacizumab (Avastin) in keratoplasty patients with corneal neovascularization (NV). Methods Retrospective case series: nine eyes of nine patients with corneal transplant and corneal NV were studied. NV was graded for depth (superficial, deep), extent (clock hours), centricity and intensity. Three patients received subconjunctival bevacizumab 2.5mg/0.1ml. Five patients were treated with topical bevacizumab 5mg/ml 4 times daily for 1 month. One patient first received injection, followed by topical bevacizumab. Follow up was up to 6 months. Results Corneal NV partially regressed in 8 out of 9 patients. The extent decreased from 7.4±3.8 to 5.6±3.4 and from 8.7±5.8 to 5.3±4.5 clock hours after treatment in patients that received topical and subconjunctival bevacizumab respectively. The centricity changed only in one patient with eye drops. The greatest effect was seen in intensity with decrease from 2.6±0.5 to 1.4±0.9 and from 2.3±0.6 to 1±0.0 in topical and subconjunctival group respectively. One patient who received both subconjunctival and topical bevacizumab only showed response to topical treatment(decrease in intensity). NV regression was noticed 2 days after injection, response was maximal after 1 week, however NV regrowth started at 1 month follow up in all patients. Decrease in NV in topical group was seen after 1 week with maximum response after 1 month. One patient developed persistent epithelial defect 1 month after injection, no other adverse effects were noted. Conclusion Topical and subconjunctival bevacizumab may be effective in inducing regression of corneal NV in keratoplasty patients. Further studies are needed to prove the effect and its duration.

Anestesia tópica más subconjuntival versus retrobulbar en la esclerectomía profunda no penetrante

To compare the safety and efficacy of topical plus subconjunctival versus retrobulbar anesthesia for primary non-penetrating sclerectomy supplemented with adjuntive 5-FU. A prospective study of 30 consecutive patients who were randomized to receive subconjunctival (n = 14) or retrobulbar (n = 16) anesthesia was performed. Operating conditions, patient comfort, postoperative pain, total pain and surgical outcomes were evaluated. There were no differences in the operating conditions. The retrobulbar group reported significantly more pain during administration of the anesthetic agent than the subconjunctival group (P= 0.00). The subconjunctival group reported more discomfort during surgery than the retrobulbar group (P= 0.00); however, this feature was not a problem for the surgeon. No statistically significant differences were found in regard to the total pain experienced, the postoperative pain, nor the success rates of the operative procedure in either group. Topical/subconjunctival anesthesia is a safe and effective alternative to retrobulbar anesthesia for non penetrating sclerectomy supplemented with 5-FU.

Comparison of Topical and Subconjunctival Anesthesia in Intravitreal Injection Administrations

To compare the effectiveness of topical and subconjunctival anesthesia in intravitreal injection administrations. Twenty-eight patients from a university clinic with bilateral diabetic macular edema were prospectively randomized to receive intravitreal injection of 4 mg triamcinolone under topical anesthesia for one eye and subconjunctival anesthesia for the other eye by using lidocaine 4%. Patients were asked to grade the pain they experienced during administration of both anesthesia and intravitreal injection by using a 4-point pain scale: from 0=no pain to 3=severe pain. Complications that developed during both procedures were recorded. The mean pain score experienced during subconjunctival injections was 0.78+/-0.62, whereas no anesthesia-related pain was reported in the topical group. The mean pain score experienced during intravitreal injection was 1.64+/-0.67 in the topical and 0.85+/-0.52 in the subconjunctival group (p<0.001). The mean total pain scores of both procedures were 0.82+/-0.34 in the topical and 0.82+/-0.51 in the subconjunctival group (p>0.05). Nine eyes (32%) developed subconjunctival haemorrhage after subconjunctival injection, whereas no anesthesia-related complication developed in the topical group. Subconjunctival haemorrhage was also observed in 5 eyes (18%) in the topical group and in 11 eyes (40%) in the subconjunctival group (p>0.05) after intravitreal injection. Although subconjunctival anesthesia provides better pain control during intravitreal injections, its application is more painful and leads to subconjunctival haemorrhage. Moreover, the mean total pain scores are similar in both methods. Therefore, topical anesthesia may be more suitable for daily practice.

Functional Health Status of Patients at Initial Visit in Primary Eye Clinic Assessed Using the Japanese Versions of the COOP Charts

Patient health status was evaluated using Japanese versions of COOP charts. The subconjunctival hemorrhage group scored 3.6 in overall health and 3.7 in change in health. The painful outer eye disease group scored higher than 3.0 in feeling, pain, change in health, and quality of life. The seeing floaters group scored higher than 3.0 in feeling, overall health, change in health, and quality of life.

Effect of mitomycin C on ciliary body and intraocular pressure with various application depths: an experimental study

To evaluate the effects of mitomycin C (MMC) on intraocular pressure (IOP) and ciliary body via transmission electron microscopy when applied under conjunctiva or different depths of sclera, without performing any filtering surgery. Thirty-six eyes of 36 New Zealand albino rabbits were used in this study. MMC was prepared in a concentration of 0.4 mg/mL and 0.05 cc (20 microg) was soaked in preprepared sterile surgical sponges. Six groups each consisting of six eyes were formed and IOP was measured preoperatively. Group 1 was the control group: the superior conjunctiva was opened and only irrigated with balanced salt solution (BSS). In group 2, MMC soaked sponges were applied under the conjunctiva. In groups 3 and 4, a scleral flap of approximately 1/3 scleral thickness was prepared and in groups 5 and 6, and a scleral flap of approximately 2/3 scleral thickness was prepared, all with a standard size of 4 x 4 mm. MMC soaked sponges were applied under these areas for 5 min in eyes in groups 3 and 5 followed by an irrigation of the relevant areas with 10 cc BSS, whereas only irrigation with BSS was done in groups 4 and 6 as control groups. No filtering procedure was performed in any of the eyes. Eyes were enucleated on the 30th day following measurement of IOP and the ciliary body regions were evaluated using transmission electron microscopy. Kruskal-Wallis test was used for the statistical assessment of IOP between groups. The deep scleral flap group (group 5) showed statistically significantly more IOP reduction than both the superficial scleral flap group (group 3; P = 0.004) and the subconjunctival group (group 2; P = 0.002) on postoperative day 30. Electron microscopic evaluation of the surgical groups revealed a wide range of different histopathological effects due to different MMC application methods. The histopathological changes were more evident in the group 5, where MMC was applied under deep scleral flap. Subscleral application of MMC seems to provide greater IOP decrease than subconjunctival application, possibly caused by a more significant ciliary body toxicity. This may be the beginning of a non-penetrating, easy to perform and safe method to decrease IOP in glaucoma patients, which the authors call 'toxic ciliary ablation surgery'. However, the long-term results and complications must be assessed with further studies.

Subconjunctival Versus Peribulbar Anesthesia in Trabeculectomy: A Prospective, Randomized Study

To compare the use of subconjunctival and peribulbar anesthesia for trabeculectomy. Sixty patients undergoing trabeculectomy were prospectively randomized to receive either peribulbar or subconjunctival anesthesia. Peribulbar anesthesia consisted of a 3-ml inferior and a 1-ml superior injection of a 1:1 mixture of 2% mepivacaine, 0.75% bupivacaine, and hyaluronidase. Subconjunctival anesthesia consisted of a 1- to 2-ml injection of the same mixture without hyaluronidase in the superotemporal quadrant. Intraoperative pain, presence of eye movements, and complications during surgery were evaluated. The frequency and intensity of pain was statistically similar between the two groups. All episodes of pain (20% in the subconjunctival group and 6.6% in the peribulbar group) were rated as mild. Eye movement was more common in the subconjunctival group than in the peribulbar group, but it was controlled by verbal command and did not interfere with the procedure. No clinically significant complications occurred during surgery. Subconjunctival anesthesia is an effective alternative to peribulbar anesthesia for trabeculectomy.