Glaucoma surgery experiments using digital microscope-integrated optical coherence tomography and OCT-compatible instruments

There is a certain failure rate in traditional glaucoma surgery because of the lack of depth information in microscope images.In this work,we present a digital microscope-integrated optical coherence tomography(MIOCT)system and several custom-made OCT-compatible instruments for glaucoma surgery.Sixteen ophthalmologists were asked to perform trabeculectomy and canaloplasty on live porcine eyes using the system and instruments.After surgery,a subjective feedback survey about the user experience was taken.The experiment results showed that our system can help surgeons easily locate important tissue structures during surgery.The custom-made instruments also solved the shadowing problem in OCT imaging.Surgeons preferred to use the system in their future practice.

Hyperglycemic Effects of a Periocular Dexamethasone Injection in Diabetic Patients after Vitreoretinal Surgery

Objective To examine the hyperglycemic effects of periocular dexamethasone injection in type 2 diabetic patients after vitreoretinal surgery （VRS）. Methods This was a retrospective non-randomized controlled trial. Twenty consecutive hospitalized patients with type 2 diabetes and ocular inflammatory reaction after VRS were enrolled in this study. Ten patients received 2.5 mg dexamethasone and 10 patients received 5 mg dexamethasone. Fourteen consecutive type 2 diabetic patients without ocular inflammatory reaction after VRS were used as control group. We measured fasting blood glucose （FBG） and at 2 h after each meal （post prandial glucose, PBG; 09：00, 13：00, and 19：00 h） after periocular dexamethasone injection. Differences among three groups were determined by q tests. Results The PBG levels in both dexamethasone-treated groups started to increase within 5 h after injection （i.e., PBG at 13：00 h）, and were significantly increased at 29：00 h after injection （P〈0.05）. BG levels were almost 2-fold higher than at baseline and compared with the control group. The BG values declined gradually by 24 h to 48 h after injection. There were no differences in BG levels between the two dexamethasone-treated groups （P〉0.05）, except for PBG at 19：00 h on day 2 after injection （P〈0.05）. Conclusion Periocular dexamethasone injection can cause transient hyperglycemia in diabetic patients after VRS. BG monitoring should be performed following such injection.

Perfluorocarbon in vitreoretinal surgery and preoperative bevacizumab in diabetic tractional retinal detachment

AIM: To describe the en bloc perfluorodissection(EBPD) technique and to demonstrate the applicabilityof using preoperative intravitreal bevacizumab duringsmall-gauge vitreoretinal surgery(23-gauge transconjunctival sutureless vitrectomy) in eyes with advancedproliferative diabetic retinopathy(PDR) with tractionalretinal detachment(TRD).METHODS: This is a prospective, interventional caseseries. Participants included 114(eyes) with advancedproliferative diabetic retinopathy and TRD. EBPD wasperformed in 114 eyes(consecutive patients) during23-gauge vitrectomy with the utilization of preoperativebevacizumab(1.25 mg/-0.05 mL). Patients mean age was 45 years(range, 21-85 years). Surgical time had a mean of 55 min(Range, 25-85 min). Mean follow up of this group of patients was 24 mo(range, 12-32 mo). Main outcome measures included best-corrected visual acuity(BCVA), retinal reattachment, and complications.RESULTS: Anatomic success occurred in 100%(114/-114) of eyes. Significant visual improvement [≥ 2 Early Treatment Diabetic Retinopathy Study(ETDRS) lines] was obtained in 69.2%(79/-114), in 26 eyes(22.8%) BCVA remained stable, and in 8 eyes(7%) BCVA decreased(≥ 2 ETDRS lines). Final BCVA was 20/-50 or better in 24% of eyes, between 20/-60 and 20/-400 in 46% of eyes, and worse than 20/-400 in 30% of eyes. Complications included cataract in 32(28%) eyes, iatrogenic retinal breaks in 9(7.8%) eyes, vitreous hemorrhage requiring another procedure in 7(6.1%) eyes, and phthisis bulbi in 1(0.9%) eye.CONCLUSION: This study demonstrates the usefulne-ss of using preoperative intravitreal bevacizumab and EBPD during smallgauge vitreoretinal surgery in eyes with TRD in PDR.

Primary 23-gauge vitreoretinal surgery for rhegmatogenous retinal detachment

AIM: To report the effectiveness and safety of primary 23-Gauge (G) vitreoretinal surgery for rhegmatogenous retinal detachment (RRD). · METHODS: In this retrospective study, 49 eyes of 49 consecutive patients who underwent primary 23-G transconjunctival sutureless vitrectomy (TSV) for RRD between January 2007 and July 2009 at our institution were evaluated. · RESULTS: Mean follow-up time was 8.9±7.7 months (1-28 months). Retinal reattachment was achieved with a single operation in 47(95.9%) of 49 eyes. In two eyes (4.1%), retinal redetachment due to new breaks was successfully treated with reoperation using the 23-G TSV system. Mean logMAR visual acuity was 2.01±0.47 preoperatively and 1.3±0.5 postoperatively (P <0.001, Paired t -test). Mean preoperative intraocular pressure (IOP) was 14.1±2.8mmHg. Mean postoperative IOP was 12.3±3.6mmHg at 1 day, 13.1±2.1mmHg at 1 week, 14.3±2.2mmHg at 1 month. Iatrogenic peripheral retinal break was observed in 1 eye(2.0%) intraoperatively. No sutures were required to close the scleral or conjunctival openings, and no eyes required convertion of surgery to 20-G vitrectomy. · CONCLUSION: Primary 23-G TSV system was observed to be effective and safe in the treatment of RRD.

Clinical observations of vitreoretinal surgery for four different phenotypes of X-linked congenital retinoschisis

AIM： To evaluate the outcomes of vitreoretinal surgery for four different phenotypes of X-linked retinoschisis （XLRS）. METHODS： This study included thirty-one eyes of 25 patients who developed XLRS with severe complications. Among the 31 eyes, there were 7 eyes with vitreous hemorrhage, 8 eyes with retinal detachment and vitreous hemorrhage, and 16 eyes with rhegmatogenous retinal detachment. All of the patients underwent standard three-port pars plana vitrectomy. All of the eyes were divided into 4 groups before surgery according to a modified classification scheme, with the first three groups as follows： group A, with foveal cystic schisis; group B with macular lamellar schisis; and group C with foveolamellar changes. Peripheral schisis was not present in these 3 groups; however, group D was a complex group with both macular and peripheral changes. One year after surgery, we analyzed the best corrected visual acuity and postoperative anatomical and functional outcomes of these 4 groups. RESULTS： There were 7 eyes in group A （22.6%）, 1 eye in group B （3.2%）, 15 eyes in group C （48.4%） and 8 eyes in group D （25.8%）. Postoperative anatomical and functional outcomes were satisfactory at the last visit, while the mean visual acuity was increased to 0.27±0.11, with a significant difference （t=-1.049, P=0.000） compared with the results before surgery （0.1±0.08）. Visual acuity was improved in 23 eyes （74.2%）. Complications were found in three eyes： two eyes with proliferative vitreoretinopathy and traction retinal detachment 10 and 12mo after surgery, respectively; and one eye with vitreous hemorrhage 15mo after surgery. These eyes were in groups C and D. The retinas remained attached in these 3 eyes after reoperation. CONCLUSION： We should pay greater attention to XLRS with foveolamellar changes because it is the most changeable phenotype. Once complications occur, vitreoretinal surgery can significantly improve visual acuity and restore the anatomic structure of the retina.

Combining robot-assisted surgical system and 3D visualization system for teaching minimally invasive vitreoretinal surgery

AIM:To investigate the feasibility of teaching minimally invasive vitreoretinal surgery with a robot-assisted surgical system and a three-dimensional(3D) visualization system.METHODS:Enucleated porcine eyes were established as an animal model for removing foreign bodies.Forty medical students were recruited to remove foreign bodies to compare the traditional microscope and the 3D system.One junior resident performed the surgical task with manual and robot-assisted operations on 20 porcine eyes for each group.One senior surgeon evaluated the retinal invasion by a graded injury degree.The learning curve for minimally invasive vitreoretinal surgery was described.RESULTS:Compared with the robot-assisted group,the injury degree was higher in the manual group.For the first ten surgeries,the manual and robot-assisted groups had injuries of 2.60±1.35(4 to 0) and 1.80±1.62(4 to 0),respectively.For the last ten surgeries,the injury degrees were 1.90±1.20(3 to 0) and 0.80±0.42(1 to 0).Considering the manual and robot-assisted groups together,95%,75% and 60% of the students considered surgical manipulation with the 3D visualization system to be more comfortable,easier and clearer,respectively.CONCLUSION:The robot-assisted surgical system and 3D visualization system may have value in teaching minimally invasive vitreoretinal surgery.

Corneal epithelial defects following vitreoretinal surgery:incidence and outcomes from the DISCOVER study

AIM:To investigate the incidence,risk factors,clinical course,and outcomes of corneal epithelial defects(CED)following vitreoretinal surgery in a prospective study setting.METHODS:This was a post-hoc analysis of all participants in DISCOVER intraoperative optical coherence tomography study.Subjects with CED 1 d after surgery without intraoperative corneal debridement was defined as the postoperative CED group.Subjects who underwent intraoperative debridement were defined as intraoperative debridement group.Eyes were matched 2:1 with controls(eyes without postoperative CED)for comparative assessment.The primary outcomes were the incidence of CED on postoperative day one and the incidence of required intraoperative debridement.Secondary outcomes included time to defect closure,delayed healing(>2 wk),visual acuity(VA)and presence of scarring at one year and cornea consult.RESULTS:This study included 856 eyes that underwent vitreoretinal surgery.Intraoperative corneal debridement was performed to 61(7.1%)subjects and postoperative CED developed spontaneously in 94(11.0%)subjects.Significant factors associated with postoperative CED included prolonged surgical duration(P=0.003),diabetes mellitus(P=0.04),postoperative ocular hypotension(P<0.001).Prolonged surgical duration was associated with intraoperative debridement.Delayed defect closure time(>2 wk)was associated with corneal scar formation at the end of the 1 y in all epithelial defect subjects(P<0.001).The overall rate of corneal scarring for all eyes undergoing vitrectomy was 1.8%.CONCLUSION:Prolonged duration of surgery is the strongest factor associated with both intraoperative debridement and spontaneous postoperative CED.Delayed defect closure is associated with a greater risk of corneal scarring at one year.The overall rate of corneal scarring following vitrectomy is low at<2%.

Surgical Management of Lumbar Spinal Canal Stenosis with Instrumentation at the Yaounde Central Hospital: Comparison of Unilateral versus Bilateral Pedicle Screw Fixation Combined with Transforaminal Lumbar Interbody Fusion

Introduction: The choice of adopting unilateral pedicle screw fixation or using bilateral pedicle screw fixation in lumbar spinal stenosis remains controversial. In our context, very few studies have been performed comparing the clinical effectiveness of unilateral versus bilateral fixation in the surgical management of lumbar spinal canal stenosis. Objective: Evaluate the impact on quality of life and clinical efficacy of unilateral spondylodesis compared to bilateral spondylodesis in the surgical management of lumbar spinal canal stenosis at the Yaounde Central Hospital. Methods: This was a retrospective descriptive cross-sectional study for a period of 4 years, from June 2015 to June 2019. It involved all patients operated for lumbar canal stenosis and who underwent spondylodesis or spinal fusion at the neurosurgery department of the Yaounde Central Hospital. Results: A total of 68 participants were recruited during our study period. 32 (47%) of the study population were in the 50 - 60 age group, with a mean age of 56.98 years ranging from 41 to 75 years. Females, housewives and farmers were the most affected. In our study, 72% of patients had unilateral spondylodesis and 28% had bilateral fusion. Preoperatively, 71% of patients had insurmountable pain, refractory to medical treatment. At 3 months postoperatively, 73.7% of patients with bilateral setup had moderate pain compared to 69% of those with unilateral setup. At 6 months postoperatively, 79% of patients with bilateral fusion had mild pain compared to 82% of patients with unilateral setup. At 1 year postoperatively, all patients had mild pain. Preoperatively, 66.2% of patients were unable to walk and 19.1% of patients were bedridden according to the Oswestry score. At 3 months postoperatively, 10.2% of patients with unilateral setup were unable to walk compared to 10.5% of patients with bilateral fixation, while 67.3% of patients with unilateral fixation had moderate disability compared to 52.6% of patients with bilateral fixation. At 6 months postoperatively, 51% of patients with unilateral setup had moderate disability compared to 47.4% of patients with bilateral fixation, while 42.9% of patients with unilateral fixation had mild disability compared to 42.1% of patients with bilateral fixation. At 1 year postoperatively, 81.6% of patients who underwent unilateral fixation had only mild disability compared to 73.7% of patients with bilateral fixation. Conclusion: The assessment of quality of life according to the set-up used shows similar results at 3 months, 6 months and 1 year, with no statistically significant differences. Single-sided pedicle screw fixation combined with transforaminal lumbar interbody fusion or mounting has the advantage of being faster, with less bleeding and is less expensive compared to bilateral fixation.

Outcome Values of Adding Sodium Bicarbonate, Dexamethasone and Fentanyl to Local Anesthetic in Peribulbar Block during Vitreoretinal Surgeries. A Randomized Prospective Study

Background and aims: we aimed to detect the outcome values of adding fentanyl, dexamethasone and sodium bicarbonate to mixture of local anesthetic in peribulbar block for vitreoretinal surgery. Methods: 120 adult ASA I & II patients, admitted for vitreoretinal surgery under peribulbar block were included in this comparative study. This study included 4 groups: Group I: (30) patients using a mixture of 1 ml normal saline, 4 ml lidocaine 2% plus 4 ml from bupivacaine 0.5% 20 ml vial containing hyaluronidase 1500 IU. Group II: (30) patients using a mixture of 1 ml of sodium bicarbonate (from 1 ml sodium bicarbonate 8.4% diluted in 10 ml normal saline), 4 ml lidocaine 2% plus 4 ml from bupivacaine 0.5% 20 ml vial containing hyaluronidase 1500 IU. Group III: (30) patients using a mixture of 1 ml fentanyl 20 μg (from a mixture of fentanyl 100 μg diluted in 5 ml normal saline), 4 ml lidocaine 2% plus 4 ml from bupivacaine 0.5% 20 ml vial containing hyaluronidase 1500 IU. Group IV: (30) patients using a mixture of 1 ml of 4 mg dexamethasone (1 ampoule = 8 mg/2 ml), 4 ml lidocaine 2% plus 4 ml from bupivacaine 0.5% 20 ml vial containing hyaluronidase 1500 IU. We measured the onset and duration of anesthesia, IOP, eyelid and global akinesia, postoperative pain by numerical pain rating scale, first analgesic requirement and postoperative side effects. Results: No significant differences were detected among the four groups as respect to age, sex and the intraocular pressure (IOP) before the anesthesia block. While the intraocular pressure (IOP) after the anesthesia block there was a significant difference, as IOP was markedly decreased postoperatively in group II compared with other groups. As regard to the onset & duration of anesthesia there was significant difference among all groups, there was rapid onset and prolonged duration of anesthesia in group III compared with other groups (1.77 ± 0.63 & 5.03 ± 0.89) respectively. As regard the onset of lid akinesia there was significant difference among the four groups with better outcome in group III, as in group III represented the most rapid onset of lid akinesia. As respecting to the onset of global akinesia there was significant difference among the four groups. There was better outcome in group III as it represented more rapid onset of global akinesia compared with other groups. There were significant differences among the four groups as regard postoperative pain all over 6 hours, better results were in group III (0.27 ± 0.69) compared with group I (2.23 ± 1.17), group II (2.00 ± 1.70), group IV (0.67 ± 0.71). As regarding to the first time for analgesic requirement there were significant differences among groups, there was no request for analgesia with better outcome in group III with increasing need to the analgesic medication in group I compared to group II and group IV. As regard side effects postoperatively there were few side effects in all groups with few numbers of cases in groups III only one patient. Although these differences in number of patients are not significant among the four groups. Conclusion: Addition of sodium bicarbonate to local anesthetic mixture was the best way in lowering the IOP other than other groups and addition of fentanyl to local anesthesia provided more rapid onset and duration of anesthesia, more rapid onset and duration for lid and global akinesia, less pain, less analgesic requirement and minimal side effects than the other groups.

A novel temporary keratoprosthesis technique for vitreoretinal surgery

AIM:To investigate the safety of vitreoretinal surgery when using a soft contact lens as a temporary keratoprosthesis(TKP)in patients with severe corneal opacifications.METHODS:Three patients with simultaneous corneal and vitreoretinal pathology were treated with a soft contact lens that was used as a TKP to facilitate vitreoretinal surgery.The soft contact lens was fixated with sutures onto the globe so that no leakage was possible.RESULTS:Vitreoretinal surgery with excellent fundus view was possible in all cases.The soft contact lens allowed safe central and peripheral vitrectomy.Surgery was successful in all cases.CONCLUSION:A soft contact lens properly fixated on the globe can successfully replace a TKP.This surgical procedure has several advantages like one size fits all,low costs,and easy access to the material.

Expandable pedicle screw instrumentation plus cement augmentation in surgery for severely osteoporotic spine

Objective To evaluate short-teerm clinical and radiographic results of a novel expandable pedicle screw instrumentation combined with cement augmentation in surgery for severely osteoporotic spine.Methods From October 2006 to October

Axial length,vitreoretinal pathology,and anterior chamber depth can predict postoperative refractive outcomes in phacovitrectomy/silicone oil removal

AIM:To evaluate the postoperative refractive prediction error(PE)and determine the factors that af fect the refractive outcomes of combined pars plana vitrectomy(PPV)or silicone oil removal(SOR)with cataract surgery.METHODS:The study is a retrospective,case-series study.Totally 301 eyes of 301 patients undergoing combined PPV/SOR with cataract surgery were enrolled.Eligible individuals were separated into four groups according to their preoperative diagnoses:silicone oil-filled eyes after PPV(group 1),epiretinal membrane(group 2),macular hole(group 3),and primary retinal detachment(RD;group 4).The variables af fecting postoperative refractive outcomes were analyzed,including age,gender,preoperative best-corrected visual acuity(BCVA),axial length(AL),keratometry average,anterior chamber depth(ACD),intraocular tamponade,and vitreoretinal pathology.The outcome measurements include the mean refractive PE and the proportions of eyes with a PE within±0.50 diopter(D)and±1.00 D.RESULTS:For all patients,the mean PE was-0.04±1.17 D,and 50.17%of patients(eyes)had a PE within±0.50 D.There was a significant difference in refractive outcomes among the four groups(P=0.028),with RD(group 4)showing the least favorable refractive outcome.In multivariate regression analysis,only AL,vitreoretinal pathology,and ACD were strongly associated with PE(all P<0.01).Univariate analysis revealed that longer eyes(AL>26 mm)and a deeper ACD were correlated with hyperopic PE,and shorter eyes(AL<26 mm)and a shallower ACD were correlated with myopic PE.CONCLUSION:RD patients have the least favorable refractive outcome.AL,vitreoretinal pathology,and ACD are strongly associated with PE in the combined surgery.These three factors affect refractive outcomes and thus can be used to predict a better postoperative refractive outcome in clinical practice.

Hand-Held Surgical Instrument with the Function of Self-Locking for Minimally Invasive Surgery

In order to improve the flexibility of the surgical instruments, a wire-driven wrist-like structure is proposed in this paper. The instrument has three degrees of freedom (DOFs) of rotation, yaw, opening and closing. Furthermore, we also acknowledge no coupling motion for each DOF. Moreover, the self-locking motion contributes to sustaining joint posture under external force. A static analysis for the end effector was conducted using the ANSYS software. At the end of this paper, a series of experiments for the prototype was performed. The results revealed that for the same surgical task, the proposed instrument had higher flexibility and the completion time of the operation tasks was obviously less than that of the traditional instrument. The results of the self-locking and operating force test showed that the surgical instruments perform well in maintaining joint posture under the force of 8.2N. The proposed surgical instrument meets the requirements of minimally invasive surgery (MIS).

Vitreoretinal surgical training-assessment of simulation,models,and rubrics-a narrative review

Background and Objective:Vitreoretinal surgery requires fine micro-surgical training and handling of delicate tissue.To aid in the training of residents and fellows,unique educational modalities exist to help facilitate the development of these microsurgical skills.From virtual simulators to artificial eye models,simulation of the posterior segment has gained an increased focus in vitreoretinal surgical training programs.Development of surgical curricula for vitreoretinal training and attainment of surgical milestones has been a key component in integrating these educational training modalities.We will explore various simulators,eye models,and potential rubrics and discuss unique ways each may help and complement one another to train future vitreoretinal surgeons.Methods:We conducted a systematic PubMed search of various review studies(from publications in English ranging from January 1978 to December 2020)discussing surgical simulators,eye models,and surgical rubrics for vitreoretinal surgery and their potential impacts upon training.Key Contents and Findings:Our review assesses the benefits and applicability of various simulators,eye models,and surgical rubrics upon training.Conclusions:Utilization of vitreoretinal surgical training tools may aid in complementing the hands-on surgical training experience for vitreoretinal surgical fellows.By using simulators and rubrics,we may better be able to standardize training for reaching vitreoretinal surgical milestones and providing adequate feedback to improve surgical competency and ultimately patient outcomes.

Change in Functional Status from Preoperative to One Year Postoperative in Patients Who Have Undergone Elective Open-Heart Surgery: A Repeated-Measures Study

Purpose: Although patient-related factors affect surgical outcomes, preoperative functional status is not measured by any cardiac risk score. Functional status can, however, be objectively measured using validated outcome tools such as the Late-Life Function and Disability Instrument (LLFDI). The purpose of this study was to determine 1) if there was a change over time in functional status, as measured by the LLFDI, in patients who underwent elective cardiac surgery, and if so, 2) what specific aspect(s) of functional status changed. Methods: A prospective longitudinal study of one year was conducted on elective cardiac surgery patients (n = 43) using the self-reported LLFDI, which measures Disability Frequency (frequency of participation in social tasks), Disability Limitation (ability to participate in social tasks) and Function Total (ease in performing routine activities). Higher scores indicate increased function and decreased disability. LLFDI scores were compared at three times (preoperative, six-week and one-year postoperative) using repeated measures ANOVA. Post hoc pairwise comparison was conducted for specific interactions. Results: Both Function Total and Disability Frequency significantly changed over time (p = 0.047 and p = 0.013, respectively). Specifically, patients’ function level was significantly higher one-year postoperative compared to preoperative (M difference = +3.48, SE = 1.48, p = 0.026). Likewise, Disability Frequency scores were significantly higher (i.e. more active) at one-year postoperative versus preoperative (M difference= +5.98, SE = 2.19, p = 0.033). Disability Limitation scores were not significantly different between any time points (p > 0.05). Conclusion: By one-year postoperative, patients demonstrated increased ease in their routine physical activities and were more participatory in social life tasks. Individuals who underwent elective cardiac surgery took more than six weeks to detect notable improvement in functional status, which was expected with a sternotomy approach. This study provides support for the use of the LLFDI as an effective tool to capture functional status in the cardiac population. These findings may assist cardiac patients in recovery timeline expectations.

夜间急诊腹腔镜手术器械的超声波清洗效果及影响因素研究

目的 探讨夜间急诊腹腔镜手术器械的超声波清洗效果及影响因素。方法 选取超声波清洗的698次夜间急诊腹腔镜手术器械作为研究对象,统计其超声波清洗质量不合格情况,对可能导致超声波清洗质量不合格的因素进行单因素和多因素二元Logistic回归方程分析。结果 夜间急诊腹腔镜手术器械的698次超声波清洗中,共有55次(7.88%)清洗质量不合格。单因素及多因素二元Logistic回归分析结果显示,清洗时距手术结束时间≥10 h、管腔类手术器械、预处理不规范、清洗水质不合格和清洗介质不合格是导致夜间急诊腹腔镜手术器械超声波清洗质量不合格发生的危险因素(OR>1,P<0.05),而手工+超声波清洗为避免夜间急诊腹腔镜手术器械超声波清洗质量不合格发生的保护性因素(OR<1,P<0.05)。结论 夜间急诊腹腔镜手术器械的超声波清洗质量不合格率较高,在手术结束后应尽早对其进行清洗,在超声波清洗前,尽量先进行手工清洗,尤其对于难清洗的管腔类手术器械,还应进行规范的预处理、选择合格的清洗水质和介质。

Characteristics of macular microvasculature before and after idiopathic macular hole surgery

AIM:To evaluate the macular microvasculature before and after surgery for idiopathic macular hole(MH)and the association of preoperative vascular parameters with postoperative recovery of visual acuity and configuration.METHODS:Twenty eyes from 20 patients with idiopathic MH were enrolled.Optical coherence tomography angiography(OCTA)images were obtained before,2 wk,1,and 3 mo after vitrectomy with internal limiting membrane peeling.Preoperative foveal avascular zone(FAZ)area and perimeter and regional vessel density(VD)in both layers were compared according to the 3-month best-corrected visual acuity(BCVA).RESULTS:The BCVA improved from 0.98±0.59(log MAR,Snellen 20/200)preoperatively to 0.30±0.25(Snellen 20/40)at 3 mo postoperatively.The preoperative deep VD was smaller and the FAZ perimeter was larger in the 3-month BCVA<20/32 group(all P<0.05).A significant reduction was observed in FAZ parameters and all VDs 2 wk postoperatively.Except for deep perifoveal VD,all VDs recovered only to their preoperative values.The postoperative FAZ parameters were lower during follow-up.Decreases in preoperative deep VDs were correlated with worse postoperative BCVA(Pearson’s r=-0.667 and-0.619,respectively).A larger FAZ perimeter(Spearman’s r=-0.524)and a lower deep perifoveal VD preoperatively(Pearson’s r=0.486)were associated with lower healing stage.CONCLUSION:The status of the deep vasculature may be an indicator of visual acuity in patients with a closed MH.Except for the deep perifoveal region,VD recovers only to preoperative levels.

Addressing the MSICS learning curve: identification of instrument-holding techniques used by experienced surgeons

AIM: To identify instrument holding archetypes used by experienced surgeons in order to develop a universal language and set of validated techniques that can be utilized in manual small incision cataract surgery(MSICS) curricula. METHODS: Experienced cataract surgeons performed five MSICS steps(scleral incision, scleral tunnel, side port, corneal tunnel, and capsulorhexis) in a wet lab to record surgeon hand positions. Images and videos were taken during each step to identify validated hand position archetypes.RESULTS: For each MSICS step, one or two major archetypes and key modifying variables were observed, including tripod for scleral incision, tripod-thumb bottom for scleral tunnel, underhand-index to thumb grip for side port, index-contact tripod for corneal entry, and tripodforceps for capsulorhexis. Key differences were noted in thumb placement and number of fingers supporting the instrument, and modifying variables included index finger curvature and amount of flexion.CONCLUSION: Identification of optimal hand positions and development of a formal nomenclature has the potential to help trainees adopt hand positions in an informed manner, influence instrument design, and improve surgical outcomes.

Ultrasonic piezotome surgery: is it a benefit for our patients and does it extend surgery time? A retrospective comparative study on the removal of 100 impacted mandibular 3rd molars

Aim of the study was to evaluate if there is a constant and significant reduction in traumaticity when mas- sively traumatic oral surgical procedures such as the removal of third molars are conducted with only ul- trasonic surgical devices (Piezotomes) expressed in a reduction of postsurgical pain and swelling on the patient’s side since such clinical experiences by the authors suggested this. Since oral surgeons criticize a higher time consumption for surgeries with Piezoto- mes also the objective time consumption was evalu- ated and compared to the traditional methods. Mate- rial and Methods: 56 female and male patients were selected that already underwent a removal of an im- pacted third mandibular molar on one side with rota- ry instruments by bone destructive burring with a still persisting comparable third mandibular molar on the contralateral side complaining about recur- rent pain episodes and were already documented for pain and swelling before. The ultrasonic surgical re- moval with the Piezotome was conducted with a buc- cal osteotomy of the compacta lateral to the impacted third molar, preservation of the resected compacta in saline solution, removal of the third molar by single or multiple dentotomy and full anatomical restitution of the surgical site with the preserved buccal com- pacta. The swelling was documented by kephalome- try 24/48/72 hours and 1 week post surgery, the pain index by the total consumption of ibuprofen-400 mg—tablets. Lesions of the mandible nerve were documented. Netto surgery time was taken from the first incision to the last suture of the procedure. Re-sults: 6 patients had to be excluded from evaluation due to incomplete post surgical follow up. A signify-cant (***, p > 0.999) decrease in pain and swelling of 50% was detected both for the parameters swelling and pain with Piezotome-surgery. No lesions of the mandible nerve were detected with Piezotome sur- gery whereas surgery with rotary instruments re- sulted in 16% hypesthesia at least up to one week. Although netto surgery time was approximately 50% longer when done with the Piezotome at the begin-ning the time consumption normalized with the growing experience of the surgeons back to the time schedule when surgery was performed with rotary instruments revealing no significant differences (-, p < 0.73). Conclusions: The results of this retrospective study suggest that Piezotome-surgery is superior in atraumaticity and soft-tissue safety compared to tra- ditional procedures with burs and grants the patients significantly less post surgical pain and swelling. Al- though—as it is with all new surgical tools and pro- tocols—surgery time is longer at the beginning when purely working with ultrasonic surgical devices time consumption reduces to normal values after a learn- ing curve.

Three-dimensional printing in paediatric orthopaedic surgery

Three-dimensional(3D)printing is a rapidly evolving and promising field to improve outcomes of orthopaedic surgery.The use of patient-specific 3D-printed models is specifically interesting in paediatric orthopaedic surgery,as limb deformity corrections often require an individual 3D treatment.In this editorial,various operative applications of 3D printing in paediatric orthopaedic surgery are discussed.The technical aspects and the imaging acquisition with computed tomography and magnetic resonance imaging are outlined.Next,there is a focus on the intraoperative applications of 3D printing during paediatric orthopaedic surgical procedures.An overview of various upper and lower limb deformities in paediatrics is given,in which 3D printing is already implemented,including posttraumatic forearm corrections and proximal femoral osteotomies.The use of patient-specific instrumentation(PSI)or guiding templates during the surgical procedure shows to be promising in reducing operation time,intraoperative haemorrhage and radiation exposure.Moreover,3D-printed models for the use of PSI or patient-specific navigation templates are promising in improving the accuracy of complex limb deformity surgery in children.Lastly,the future of 3D printing in paediatric orthopaedics extends beyond the intraoperative applications;various other medical applications include 3D casting and prosthetic limb replacement.In conclusion,3D printing opportunities are numerous,and the fast developments are exciting,but more evidence is required to prove its superiority over conventional paediatric orthopaedic surgery.