Intraoperative Changes Research Articles

Intraoperative Observation of a Macular Holes Using Optical Coherence Tomography.

PurposeThis study aimed to observe intraoperative changes in macular hole (MH) form using intraoperative optical coherence tomography (iOCT).MethodsA total of 10 eyes from 10 patients with MH who underwent vitrectomy using iOCT from May 2015 to October 2015 at the Yamagata University Hospital were retrospectively evaluated. Accordingly, 25-gauge pars plana vitrectomy using iOCT with internal limiting membrane (ILM) peeling and sulfur hexafluoride gas tamponade was performed on each patient. During surgery, MHs were observed using iOCT over four points, namely, before posterior vitreous detachment (PVD) formation, after PVD formation, after ILM peeling, and after fluid–gas exchange. Thereafter, basal MH diameter and minimum aperture MH diameter were postoperatively analyzed.ResultsBefore PVD formation, after PVD formation, after ILM peeling, and after fluid–gas exchange, the mean basal MH diameters were 690.7 ± 268.4, 683.3 ± 274.2, 683.7 ± 269.5, and 668.3 ± 261.4 μm, while the mean minimum aperture MH diameters were 278.3 ± 165.2, 283.0 ± 170.2, 257.0 ± 127.8, and 188.0 ± 105.0 μm, respectively. The mean minimum aperture MH diameter decreased significantly after fluid–gas exchange (one-way repeated measures ANOVA, p < 0.05). None of the patients exhibited intraoperative closure of the MHs. However, MH closure was confirmed in all patients after the surgery.ConclusionNone of the patients demonstrated intraoperative MHs closure. Accordingly, the minimum aperture MH diameter was the first change formation to close after fluid–gas exchange.

Spinal Anesthesia Versus General Anesthesia for Elective Lumbar Spine Surgery: A Randomized Clinical Trial

Either general or regional anesthesia can be used for lumbar disk surgery. The common anesthetic technique is general anesthesia (GA). The aim of this study was to compare the intra and postoperative outcomes of spinal anesthesia (SA) with GA in these patients.Seventy-two patients were enrolled in the study. They were randomized into two groups with 37 patients in GA Group and 35 ones in SA Group. The heart rate (HR), mean arterial pressure (MAP), blood loss, surgeons satisfaction with the operating conditions, the severity of postoperative pain based on visual analogue scale (VAS) and analgesic use were recorded.The mean blood loss was significantly less in the SA Group compared to GA Group (p < 0.05). Intraoperative maximum blood pressure and heart rate changes were significantly less in SA Group (p < 0.05). The surgeons satisfaction was significantly more in the SA Group (p < 0.05). The number of patients who used postoperative analgesic as well as postoperative mean VAS was significantly less in SA Group in comparison with GA group (p < 0.05 for both).Our study showed that SA was superior to GA in providing postoperative analgesia and decreasing blood loss while maintained better perioperative hemodynamic stability without increasing adverse side effects.

Electrocochleography in cochlear implantation: Development, applications, and future directions.

Electrocochleography (ECochG) is an electrophysiological technique that records electrical potentials generated by different components of the inner ear and peripheral cochlear nerve in response to acoustic stimulation. ECochG responses can be analyzed into (1) cochlear microphonics (CM), (2) auditory nerve neurophonics, (3) summating potential, and (4) compound action potential. Over the past few decades, there have been ongoing refinements in technique and updates in the understanding of recorded potentials. Historically, ECochG found its main application in the diagnostic evaluation of Meniere's disease (MD). However, in the last decade, the focus has shifted towards cochlear implantation (CI). In patients with residual hearing after CI, combined electric and acoustic stimulation has resulted in improved hearing and speech outcomes. Despite efforts to mitigate trauma during electrode insertion, hearing preservation rates vary after surgery. During implantation, real‐time ECochG offers an opportunity to measure frequency specific CMs elicited from a localized region in the cochlea as the surgeon inserts the electrode array. In extracochlear ECochG recordings, the recording electrode can be placed on the promontory, the stapes, or the tympanic membrane. Intracochlear ECochG can be performed by inserting a recording electrode into the cochlea or by using one of the CI electrodes as the recording electrode. The loss of intraoperative ECochG signal may indicate cochlear trauma from electrode insertion, but the association between intraoperative ECochG changes and cochlear trauma remains controversial. The ability to monitor cochlear trauma during CI electrode placement holds promise to improve hearing preservation outcomes, modify surgical techniques, and change electrode design. The goal of this review is to provide a comprehensive overview of the electrophysiology and history of ECochG, discuss its recent applications in CI, and explore the ongoing research in this expanding field.

Early postoperative clinical recovery of robotic arm-assisted vs. image-based navigated Total hip Arthroplasty

BackgroundThis study compared the early clinical recovery of total hip arthroplasty (THA) using computer navigation systems (nTHA) and robotic arm-assisted THA (rTHA).MethodsThirty prospective subjects who underwent rTHA were clinically compared to 30 subjects who underwent nTHA. Clinical data (surgical time, intraoperative blood loss, pain severity, number of days to independent walking, and Harris Hip Score (HHS) at discharge), and radiographic parameters (inclination and anteversion angles) were statistically compared between the two groups.ResultsFollow-up times were 24.3 ± 6.0 and 27.0 ± 7.0 days in the rTHA and nTHA groups, respectively. The surgical time (135.1 ± 13.9 min vs. 146.2 ± 12.8 min, p = 0.002), number of days to independent walking (7.2 ± 2.0 vs. 11.5 ± 3.0 days, p < 0.001), and postoperative pain using a numeric rating scale on postoperative days 7, 10,, and 14 (1.4 ± 0.9 vs. 2.2 ± 1.2, p = 0.005; 1.0 ± 0.8 vs. 1.8 ± 1.1, p = 0.002; 0.3 ± 0.5 vs. 1.1 ± 0.9, p < 0.001; respectively) were significantly reduced in the rTHA group compared to the nTHA group. The rTHA group showed a significantly higher postoperative HHS compared to the nTHA group (85.3 ± .3.2 vs. 81.0 ± 8.5, p = 0.014). No statistically significant difference was observed in radiographic parameters between the groups; however, the incidence of intraoperative target angle changes was significantly lower in the rTHA group than in the nTHA group (0/30 subjects [0%] vs. 11/30 subjects [36.7%], p < 0.001).ConclusionThe surgical time, postoperative pain, and number of days to independent walking were significantly shorter, and the HHS at discharge was significantly higher in the rTHA group than in the nTHA group. Thus, compared to the nTHA group, the rTHA group showed improved early clinical recovery.

Comparison of Combined Forced-Air Warming and Circulating-Water-Mattress and Forced-Air Warming Alone in Patients Undergoing Open Abdominal Surgery in Lithotomy Position: a Randomized Controlled Trial

The objective of this study was to evaluate the efficacy of warming devices in patients undergoing open abdominal surgery in lithotomy position. This randomized, controlled trial was designed to compare body temperatures of patients undergoing open abdominal surgery in lithotomy position between February and May 2019. After prewarming for 30 min with forced-air using a full-body blanket, patients were randomized to receive intraoperative warming either with forced-air using a blanket covering the upper torso and upper extremities in combination with circulating-water-mattress warming the back (Group I) or with only forced-air using blanket covering the upper torso and upper extremities (Group II). Primary outcome measure was the intraoperative change in core-body temperature using oesophageal temperature probe. A total of 28 patients were randomized. The mean core-body temperatures (Group I: 36.1 SD0.41 vs Group II: 35.9 SD0.53 °C; p=0.139) and intraoperative changes (Group I: 0.41% vs Group II: − 0.001%; p=0.306) were similar. The core-body temperature at the end of the operation correlated with the operating room temperature in Group II (r=0.862, p<0.001), but not in Group I (r=0.323, p=0.259). The combination of forced-air warming and circulating-water-mattress for open abdominal surgery in the lithotomy position may be more beneficial than forced-air warming alone, due to maintenance of the intraoperative mean core-body temperature ≥36°C, despite variations in operating room temperature. Trial Registry Number: ClinicalTrials.gov Identifier: NCT03824262 (Date of registry: 29 January 2019)

Gluteal Blood Flow Monitoring in Endovascular Aneurysm Repair With Internal Iliac Artery Embolization.

When an internal iliac artery (IIA) has to be embolized during endovascular aneurysm repair (EVAR), buttock claudication sometimes poses problems. However, there is no established method to evaluate intraoperative blood flow to the gluteal muscles.Methods and Results:Gluteal regional oxygen saturation (rSO2) was monitored using near-infrared spectroscopy (NIRS) during surgery, and changes in rSO2were compared with treatment results. Twenty-seven patients who underwent EVAR and IIA embolization at our institution between April 2019 and May 2020 were included in this study. The association between intraoperative changes in rSO2and postoperative incidence of buttock claudication was analyzed. Furthermore, the presence or absence of communication between the superior and inferior gluteal arteries and the intraoperative changes in rSO2were compared to ascertain whether rSO2reflects blood flow change. Postoperative buttock claudication occurred in 4 of 19 patients (21%) with unilateral occlusion of IIA and in 4 of 8 patients (50%) with bilateral occlusion of IIAs. rSO2was found to decrease significantly further in patients with buttock claudication than in patients without buttock claudication (-15±12% vs. -4±16%, P<0.05). In addition, rSO2was predominantly lower in patients without the communication between the superior and inferior gluteal arteries than in those with the communication. Gluteal rSO2is useful as an indicator of intraoperative gluteal blood flow.

Accuracy of a portable accelerometer-based navigation system for cup placement and intraoperative leg length measurement in total hip arthroplasty: a cross-sectional study

BackgroundComplications after total hip arthroplasty (THA) are frequently the consequence of malpositioned components or leg length discrepancy after surgery. Recently, a new version of a portable, accelerometer-based hip navigation system (New HipAlign) was made available with a change in the method of measuring cup abduction and the addition of a leg length measurement function. The purposes of this study were to investigate cup positioning and to examine the accuracy of leg length measurement with New HipAlign.MethodsCups were implanted and intraoperative leg length change was measured using New HipAlign in 60 THAs through a posterior approach in the lateral decubitus position. The cup position and radiographic leg length change were determined postoperatively on pelvic radiograph and computed tomography scans. We previously compared cup positioning with a previous version of a portable, accelerometer-based hip navigation system (Previous HipAlign) and conventional surgical techniques. Cup positioning in this study was compared with the results of out previous study using Previous HipAlign.ResultsThe mean cup abduction of 40.3° ± 4.9° (range, 26° to 53°) and the mean cup anteversion of 15.8° ± 5.6° (range, 6.7° to 29.5°) were found. The deviation of the postoperative measured angles from the target cup position was 3.7° ± 3.3° for cup abduction and 5.9° ± 3.6° for cup anteversion. 56/60 of the cups were inside the Lewinnek safe zone. Compared with our previous study using Previous HipAlign, there were no significant differences with regard to cup abduction, cup anteversion, the deviation from the target cup position for cup abduction, the value of deviation for cup anteversion, and the number of cups inside the Lewinnek safe zone (P = 0.218, 0.334, 0.651, 0.797, 0.592). The mean difference between the intraoperative and radiographic leg length changes was + 0.8 ± 3.4 mm. There was significant correlation between the intraoperative and radiographic leg length changes (r = 0.804, P = 0.000).ConclusionsUse of New HipAlign allowed for accurate cup placement and reliable leg length measurement during THA.Trial registrationClinical trial is defined as ‘any research study that prospectively assigns human participants or groups of humans to one or more health-related interventions to evaluate the effects on health outcome’ by the World Health Organization (WHO). Because this study is not a clinical trial, trial registration is not needed.

Effects of body mass index and range of motion on intraoperative change in pelvic tilt during total hip arthroplasty using the direct anterior approach

BackgroundIntraoperative pelvic tilt changes that occurs during total hip arthroplasty (THA) in the supine position affects cup placement and sometimes causes malalignment. The relationship between body mass index (BMI) and pelvic movement has been reported for some procedures, but not the direct anterior approach (DAA). The purpose of this study was to investigate intraoperative pelvic tilt changes that occurs during DAA.MethodsIn this single-center, retrospective study, we reviewed 200 hips that underwent primary THA via DAA in the supine position using an accelerometer-based navigation system. Intraoperative changes in pelvic tilt and axial rotation from the start of surgery to cup placement were assessed using the navigation system. Preoperative clinical factors that increased pelvic tilt and axial rotation toward the surgical side by > 10° were analyzed via univariate and multiple logistic regression analyses.ResultsThe mean pelvic tilt value increased by 7.6° ± 3.8° (95% confidence interval [CI], 7.1–8.2; range, − 5.0–19.0) intraoperatively, and the axial rotation increased by 3.2° ± 2.7° (95% CI, 2.7–3.7; range, − 13.0–12.0). Univariate analysis revealed that the group with increased pelvic tilt showed significantly greater range of abduction and internal rotation, and significantly lower BMI than the group with no increased tilt. Pre-incisional pelvic tilt was significantly greater in the group with increased axial rotation than in the group with no increased rotation. On logistic regression analysis, BMI (odds ratio [OR], 0.889; 95% CI, 0.809–0.977; p = 0.014) and the range of internal rotation (OR, 1.310; 95% CI, 1.002–1.061; p = 0.038) were predictors of large increases in pelvic tilt. No predictors of large increases in axial rotation were identified.ConclusionSignificant forward pelvic tilt was observed in patients with a low BMI values and high ranges of internal rotation via THA using the DAA. Findings indicated that surgeons should pay attention to intraoperative pelvic movements, which may help identify patients with significant pelvic tilt changes.

Intraoperative surgical strategy changes in patients with chronic and end-stage renal disease undergoing coronary artery bypass grafting

Factors such as more diffuse atherosclerosis, plaque instability and accelerated vascular calcification in patients with chronic and end-stage renal disease (ESRD) can potentially present intraoperative challenges in coronary artery bypass grafting (CABG) procedures. We evaluated whether patients with chronic and ESRD experienced more surgical strategy changes and/or graft revisions than patients with normal renal function when undergoing CABG procedures according to a protocol for intraoperative high-frequency ultrasound and transit-time flow measurement (TTFM). Outcomes of CABG for patients with chronic and ESRD and patients with normal renal function enrolled in the multicentre prospective REQUEST (REgistry for QUality assESsmenT with Ultrasound Imaging and TTFM in Cardiac Bypass Surgery) study were compared retrospectively. The primary end point was frequency of intraoperative surgical strategy changes. The secondary end point was post-protamine TTFM parameters. There were 95 patients with chronic and ESRD and 921 patients with normal renal function. Patients with chronic and ESRD undergoing CABG according to a protocol for intraoperative high-frequency ultrasound and TTFM had a higher rate of strategy changes overall [33.7% vs 24.3%; odds ratio (OR) = 1.58; 95% confidence interval (CI) = 1.01-2.48; P = 0.047] and greater revisions per graft (7.0% vs 3.4%; odds ratio = 2.14; 95% CI = 1.17-3.71; P = 0.008) compared to patients with normal renal function. Final post-protamine graft TTFM parameters were comparable between cohorts. Patients with chronic and ESRD undergoing CABG procedures with high-frequency ultrasound and TTFM experience more surgical strategy changes than patients with normal renal function while achieving comparable graft flow. ClinicalTrials.gov NCT02385344.

The rule of brain hematoma pressure gradient and its influence on hypertensive cerebral hemorrhage operation

To comparatively study the size of and variation in the ‘brain-haematoma’ pressure gradient for different surgical methods for hypertensive intracerebral haemorrhage (HICH) and analyse the gradient’s influence on surgical procedures and effects of the haemorrhage. Seventy-two patients with HICH treated from 1/2019 to 12/2019 were randomly divided into two groups, namely, the keyhole endoscopy and large trauma craniotomy groups, according to different operative methods. Intraoperative changes in intracranial pressure (ICP) were monitored to calculate intraoperative alterations in the ‘brain-haematoma’ pressure gradient. Intraoperative characteristics (operative time, bleeding volume, volume of blood transfusion, and haematoma clearance rate) and postoperative characteristics (oedema, postoperative activities of daily living (ADL) scores, mortality rate and rebleeding rate) were compared between the two groups. In the keyhole endoscopy group, ICP decreased slowly; the ‘brain-haematoma’ pressure gradient was large, averaging 251.1 ± 20.6 mmH2O, and slowly decreased. The mean operative time was 83.6 ± 4.3 min, the mean bleeding volume was 181.2 ± 13.6 ml, no blood transfusions were given, the average postoperative haematoma clearance rate was 95.6%, the rate of severe oedema was 10.9%, and the average postoperative ADL score was 85.2%. In the large trauma craniotomy group, ICP rapidly decreased after craniotomy. When the haematoma was removed, the ‘brain-haematoma’ pressure gradient was small, averaging 132.3 ± 10.5 mmH2O, and slowly decreased. The mean operative time was 232 ± 26.1 min, the mean bleeding volume was 412.6 ± 35.2 ml, the average volume of blood transfusion was 281.3 ± 13.6 ml, and the average postoperative haematoma clearance rate was 82.3%; moreover, the rate of severe oedema was 72.1%, and the average postoperative ADL score was 39.0%. These differences were statistically significant (P < 0.05). Neither the death rate (P > 0.05, 2.7% VS 2.8%) nor rebleeding rate (P > 0.05, 2.7% VS 2.8%) showed any obvious changes. The magnitude and variation in the ‘brain-haematoma’ pressure gradient for different surgical methods significantly influence surgical procedures and effects of HICH. During keyhole endoscopy surgery, this gradient was relatively large and slowly decreased; the haematoma was therefore easier to remove. Advantages of this approach include a high haematoma clearance rate, decreased bleeding volume, decreased operative time, reduced trauma, decreased postoperative brain oedema and improved postoperative recovery of neurological function.Chinese Clinical Trial Register: ChiCTR1900020655 registration in 12/01/02,019 registration in 28/02/02,020 Number: NCOMMS-20–08,091.

Intraoperative Retinal Changes May Predict Surgical Outcomes After Epiretinal Membrane Peeling.

PurposeTo investigate whether intraoperative retinal changes during epiretinal membrane (ERM) peeling affect anatomic or functional outcomes after surgery.MethodsWe measured retinal thickness using an intraoperative optical coherence tomography (iOCT) device in patients undergoing pars plana vitrectomy with membrane peeling for idiopathic ERM. Changes in intraoperative central macular thickness (iCMT) were compared with postoperative improvements in CMT and best-corrected visual acuity (VA).ResultsTwenty-seven eyes from 27 patients (mean age 68 years) underwent iOCT-assisted ERM peeling surgery. Before surgery, mean VA was logMAR 0.50 ± 0.36 (Snellen 20/63), and mean baseline CMT was 489 ± 82 µm. Mean iCMT before peeling was 477 ± 87 µm, which correlated well with preoperative CMT (P < 0.001). Mean change in iCMT was −39.6 ± 37 µm (range −116 to +77 µm). After surgery, VA improved to logMAR 0.40 ± 0.38 (Snellen 20/50) at month 1 and logMAR 0.27 ± 0.23 (Snellen 20/37) at month 3, whereas CMT decreased to 397 ± 44 µm and 396 ± 51 µm at months 1 and 3. Eyes that underwent greater amount of iCMT change (absolute value of iCMT change) were associated with greater CMT reduction at month 1 (P < 0.001) and month 3 (P = 0.010), whereas those with greater intraoperative thinning (actual iCMT change) showed a trend toward better VA outcomes at months 1 (P = 0.054) and 3 (P = 0.036).ConclusionsIntraoperative changes in retinal thickness may predict anatomic and visual outcomes after idiopathic ERM peeling surgery.Translational RelevanceOur study suggests that intraoperative retinal tissue response to ERM peeling surgery measured by iOCT may be a prognostic indicator for restoration of retinal architecture and for visual acuity outcomes.

Factors affecting intraoperative changes in regional cerebral tissue oxygen saturation in elderly patients undergoing laparoscopic hysterectomy

Objective: To explore the factors that affect the fluctuation of intraoperative regional cerebral oxygen saturation (rSctO2) in elderly patients undergoing laparoscopic hysterectomy. Methods: A retrospective analysis of 39 elderly patients undergoing elective laparoscopic hysterectomy in Yale New Haven Hospital from October 2016 to February 2017 was performed. Factors including patients' demographic data, past medical history, intraoperative monitoring index and rSctO2 index (baseline, maximum, minimum, maximum-baseline, baseline-minimum) were recorded. Pearson correlation analysis was used to analyze the correlation between rSctO2 indexes and preoperative and intraoperative factors. Independent sample t-test was used to compare the differences of rSctO2 indexes between hypertension group and the group without hypertension, as well as diabetes group and the group without diabetes. Taking diabetes as the stratification factor, the relationship between rSctO2and factors including age, body mass index, hypertension were analyzed using multivariate analysis. Results: The age of the patients was (67.6±5.6) years old. The baseline value of rSctO2 was (71.2±3.9)% in the left frontal lobe and (70.8±4.1)% in the right frontal lobe. Results from univariate analysis showed that the left and right maximum-baseline value of rSctO2 were (12.9±4.5)% and (12.8±4.4)%, which were significantly lower than (16.3±4.2)% and (16.2±4.9)% in the group without hypertension (t=2.329, 2.266, all P<0.05). The right baseline-minimum in the group with hypertension was (5.3±3.7)%, which was significantly higher than (2.7±4.2)% in the group without hypertension (t=-2.061, P<0.05). The left minimum value of rSctO2 in diabetic group was (64.4±4.2)%, and the maximum value of rSctO2on the left and right sides were (81.7±4.0)% and (81.9±4.5)%, which were lower than (68.4±4.1)%, (86.7±4.2)% and (86.0±3.7)% in the group without diabetes (t=2.623, 3.297, 2.850, all P<0.05). The results of multivariate analysis showed the influence of age (t=2.866, P<0.05) and hypertension on left maximum-baseline (t=-4.530, P<0.01) was statistically significant. The influence of hypertension on right maximum-baseline was statistically significant (t=-4.629,P<0.01). Conclusion: Preoperative diabetes and hypertension are factors significantly affecting the intraoperative rSctO2 of elderly patients with laparoscopic hysterectomy.

Intraoperative Auditory Brainstem Response Results Predict Delayed Sensorineural Hearing Loss After Middle Cranial Fossa Resection of Vestibular Schwannoma.

To identify intraoperative neurophysiologic measures predictive of delayed progressive sensorineural hearing loss in the operative ear after a middle fossa approach (MCF) for resection of vestibular schwannoma (VS). Retrospective review. Academic, tertiary referral center. Subjects with vestibular schwannoma who underwent a MCF microsurgical resection of VS were analyzed for individuals whose hearing was initially preserved but subsequently developed progressive sensorineural hearing loss in the operative ear. Thirty-seven patients were identified for whom audiologic and neurophysiologic data was available. Intraoperative neurophysiologic changes will correlate with delayed sensorineural hearing loss in the operative ear. Audiometric evaluations, intraoperative electrocochleography (ECoG), and auditory brainstem response (ABR) measures. Twenty-five subjects experienced stable hearing or hearing loss in the operative ear comparable to the contralateral ear. Twelve subjects suffered a significant increase in the hearing asymmetry between ears. Deterioration in the amplitude of wave V of the ABR persisting at the close of tumor resection correlated with delayed sensorineural hearing loss in the operative ear (p 0.02, 5% mean improvement in the stable hearing group, versus a 14% decline with progressive asymmetry), but changes in ECoG or other auditory brainstem response parameters (p > 0.05) were not predictive. Persisting amplitude reduction of wave V of the intraoperative ABR best correlates with delayed progressive sensorineural hearing loss in the operative ear. Neither persistent changes in ECoG, other ABR parameters, nor transient changes, correlated with delayed progressive sensorineural hearing loss in the operative ear.

Association between neutrophil\u2013lymphocyte ratio change during living donor liver transplantation and graft survival

Preoperative neutrophil–lymphocyte ratio (NLR), has shown a predictive value in living donor liver transplantation (LDLT). However, the change in the NLR during LDLT has not been fully investigated. We aimed to compare graft survival between the NLR increase and decrease during LDLT. From June 1997 to April 2019, we identified 1292 adult LDLT recipients with intraoperative NLR change. The recipients were divided according to NLR change: 103 (8.0%) in the decrease group and 1189 (92.0%) in the increase group. The primary outcome was graft failure in the first year. In addition, variables associated with NLR change during LDLT were evaluated. During 1-year follow-up, graft failure was significantly higher in the decrease group (22.3% vs. 9.1%; hazard ratio 1.87; 95% confidence interval 1.10–3.18; p = 0.02), but postoperative complications did not differ between two groups. This finding was consistent for the overall follow-up. Variables associated with NLR decrease included preoperative NLR > 4, model for end-stage liver disease score, intraoperative inotropic infusion and red blood cell transfusion, and operative duration. The least absolute shrinkage and selection operator model yielded similar results. NLR decrease during LDLT appeared to be independently associated with graft survival. Further studies are needed to confirm our findings.

A Novel Hyperspectral Imaging System for Intraoperative Prediction of Cerebral Hyperperfusion Syndrome after Superficial Temporal Artery-Middle Cerebral Artery Anastomosis in Patients with Moyamoya Disease

Background: Postoperative cerebral hyperperfusion syndrome (CHS) may occur after superficial temporal artery (STA)-middle cerebral artery (MCA) bypass for moyamoya disease (MMD). Predicting postoperative CHS is challenging; however, we previously reported the feasibility of using a hyperspectral camera (HSC) for monitoring intraoperative changes in brain surface hemodynamics during STA-MCA bypass. Objective: To investigate the utility of HSC to predict postoperative CHS during STA-MCA bypass for patients with MMD. Methods: Hyperspectral images of the cerebral cortex of 29 patients with MMD who underwent STA-MCA bypass were acquired by using an HSC before and after anastomosis. We then analyzed the changes in oxygen saturation after anastomosis and assessed its correlation with CHS. Results: Five patients experienced transient neurological deterioration several days after surgery. ¹²³I-N-Isopropyl-iodoamphetamine single-photon emission computed tomography scan results revealed an intense, focal increase in cerebral blood flow at the site of anastomosis without any cerebral infarction. Patients with CHS showed significantly increased oxygen saturation (SO₂) in the cerebral cortex after anastomosis relative to those without CHS (33 ± 28 vs. 8 ± 14%, p < 0.0001). Receiver operating characteristic analysis results show that postoperative CHS likely occurs when the increase rate of cortical SO₂ value is >15% (sensitivity, 85.0%; specificity, 81.3%; area under curve, 0.871). Conclusions: This study indicates that hyperspectral imaging of the cerebral cortex may be used to predict postoperative CHS in patients with MMD undergoing STA-MCA bypass.

Second generation laryngeal mask airway during laparoscopic living liver donor hepatectomy: a randomized controlled trial

The second-generation laryngeal mask airway (LMA) provides a higher sealing pressure than classical LMA and can insert the gastric drainage tube. We investigated the difference in respiratory variables according to the use of second-generation LMA and endotracheal tube (ETT) in laparoscopic living liver donor hepatectomy (LLDH). In this single-blind randomized controlled trial, intraoperative arterial carbon dioxide partial pressure at 2 h after the airway devices insertion (PaCO2_2h) was compared as a primary outcome. Participants were randomly assigned to the following groups: Group LMA (n = 45, used Protector LMA), or Group ETT (n = 43, used cuffed ETT). Intraoperative hemodynamic and respiratory variables including mean blood pressure (MBP), heart rate (HR), and peak inspiratory pressure (PIP) were compared. Postoperative sore throat, hoarseness, postoperative nausea and vomiting (PONV), and pulmonary aspiration were recorded. The PaCO2_2h were equally effective between two groups (mean difference: 0.99 mmHg, P = 0.003; 90% confidence limits: − 0.22, 2.19). The intraoperative change in MBP, HR, and PIP were differed over time between two groups (P < 0.001, P = 0.015, and P = 0.039, respectively). There were no differences of the incidence of postoperative complications at 24 h following LLDH (sore throat and hoarseness: P > 0.99, PONV: P > 0.99, and P = 0.65, respectively). No case showed pulmonary aspiration in both groups. Compared with endotracheal tube, second-generation LMA is equally efficient during LLDH. The second-generation LMA can be considered as the effective airway devices for securing airway in patients undergoing prolonged laparoscopic surgery.Trial Registration This study was registered at the Clinical Trial Registry of Korea (https://cris.nih.go.kr. CRiS No. KCT0003711).

Patient-specific instruments do not show advantage over conventional instruments in unicompartmental knee arthroplasty at 2year follow-up: a prospective, two-centre, randomised, double-blind, controlled trial.

The aim of this two-centre RCT was to compare pre- and post-operative radiological, clinical and functional outcomes between patient-specific instrumentation (PSI) and conventional instrumented (CI) unicompartmental knee arthroplasty (UKA). It was hypothesised that both alignment methods would have comparable post-operative radiological, clinical and functional outcomes. One hundred and twenty patients were included, and randomly allocated to the PSI or the CI group. Outcome measures were peri-operative outcomes (operation time, length of hospital stay and intra-operative changes of implant size) and post-operative radiological outcomes including the alignment of the tibial and femoral component in the sagittal and frontal plane and the hip-knee-ankle-axis (HKA-axis), rate of adverse events (AEs) and patient-reported outcome measures (PROMs) pre-operatively and at 3, 12 and 24months post-operatively. There was a statistically significant difference (p < 0.05) in alignment of the femoral component in the frontal plane in favour of the CI method. No statistically significant differences were found for the peri-operative data or in the functional outcome at 2-year follow-up. In the PSI group, the approved implant size of the femoral component was correct in 98.2% of the cases and the tibial component was correct in 60.7% of the cases. There was a comparable rate of AEs: 5.1% in the CI and 5.4% in the PSI group. The PSI method did not show an advantage over CI in regard of positioning of the components, nor did it show an improvement in clinical or functional outcome. We conclude that the possible advantages of PSI do not outweigh the costs of the MRI scan and the manufacturing of the PSI. Randomised controlled trial, level I.

A novel posterior multiple screws distraction reducer system versus anterior release, posterior internal distraction, and subsequent spinal fusion for severe scoliosis

PurposeWe previously reported anterior release, posterior internal distraction, and subsequent spinal fusion (ARPIDF) for the correction of severe scoliosis with a satisfactory correction rate. However, surgical procedures were completed in 2–3 stages. Here we compare Cobb angle of ≥90° in scoliosis correction between a novel posterior multiple screws distraction reducer (MSDR) system and ARPIDF.MethodsThirty-six patients with severe scoliosis treated by MSDR or ARPIDF (n = 18 in both groups). We retrospectively analyzed and compared outcome measures between the two groups over a minimum follow-up duration of 2 years. The following variables were compared between the two groups: age at surgery, sex, etiology, flexibility of the main thoracic curve, number of fused segments and screws, operation time, estimated blood loss, hospitalization time, follow-up duration, various radiological parameters, complication rate, and Scoliosis Research Society-30 score.ResultsThere were no significant between-group differences with respect to age, sex, etiology, flexibility of the main thoracic curve, number of fused segments and screws, and follow-up duration. Further, there was no significant difference in terms of preoperative, postoperative, and final follow-up findings of the radiographic data. However, the ARPIDF group had longer operation and hospitalization times and greater blood loss. In the ARPIDF group, 4 patient developed complications (infection, intraoperative neuromonitoring changes, transient dyspnea); none of these events occurred in the MSDR group.ConclusionThe use of MSDR helped achieve greater scoliosis correction with a shorter operation time, lower blood loss, and lower complication rate than the use of ARPIDF. MSDR facilitates safer and easier correction of severe scoliosis without increasing surgical risk.

Maximal surgical resection and adjuvant surgical technique to prolong the survival of adult patients with thalamic glioblastoma

The importance of maximal resection in the treatment of glioblastoma (GBM) has been reported in many studies, but maximal resection of thalamic GBM is rarely attempted due to high rate of morbidity and mortality. The purpose of this study was to investigate the role of surgical resection in adult thalamic glioblastoma (GBM) treatment and to identify the surgical technique of maximal safety resection. In case of suspected thalamic GBM, surgical resection is the treatment of choice in our hospital. Biopsy was considered when there was ventricle wall enhancement or multiple enhancement lesion in a distant location. Navigation magnetic resonance imaging, diffuse tensor tractography imaging, tailed bullets, and intraoperative computed tomography and neurophysiologic monitoring (transcranial motor evoked potential and direct subcortical stimulation) were used in all surgical resection cases. The surgical approach was selected on the basis of the location of the tumor epicenter and the adjacent corticospinal tract. Among the 42 patients, 19 and 23 patients underwent surgical resection and biopsy, respectively, according to treatment strategy criteria. As a result, the surgical resection group exhibited a good response with overall survival (OS) (median: 676 days, p < 0.001) and progression-free survival (PFS) (median: 328 days, p < 0.001) compared with each biopsy groups (doctor selecting biopsy group, median OS: 240 days and median PFS: 134 days; patient selecting biopsy group, median OS: 212 days and median PFS: 118 days). The surgical resection groups displayed a better prognosis compared to that of the biopsy groups for both the O6-methylguanine-DNA methyltransferase unmethylated (log-rank p = 0.0035) or methylated groups (log-rank p = 0.021). Surgical resection was significantly associated with better prognosis (hazard ratio: 0.214, p = 0.006). In case of thalamic GBM without ventricle wall-enhancing lesion or multiple lesions, maximal surgical resection above 80% showed good clinical outcomes with prolonged the overall survival compared to biopsy. It is helpful to use adjuvant surgical techniques of checking intraoperative changes and select the appropriate surgical approach for reducing the surgical morbidity.

Comparison of Intraoperative Neuromonitoring Outcome in Treating Thoracic Ossification of the Ligamentum Flavum Through En Bloc Versus Piecemeal Laminectomy.

A retrospective cohort analysis. The aim of this study was to investigate the impact of piecemeal versus en bloc laminectomies on spinal cord in thoracic ossification of ligamentum flavum (TOLF) through intraoperative changes of motor-evoked potentials (MEPs) and somatosensory-evoked potentials (SEPs). Surgical treatment is indicated for symptomatic TOLF, and both piecemeal and en bloc laminectomies are commonly used methods. However, few studies compared both intraoperative interference and prognostic impact of these two laminectomies on spinal cord in TOLF patients. MEPs were recorded from abductor hallucis (AH) and tibialis anterior, and SEPs were performed on tibial nerve in 55 TOLF patients (piecemeal vs. en bloc: 23 vs. 32). Patients were categorized based on MEP/SEP improvement, deterioration, and no change, and MEP/SEP improvement rates were measured in the improvement group. Additionally, all patients were assessed by American Spinal Injury Association (ASIA) scores, Ashworth scores, and modified Japanese Orthopedic association (mJOA) scores before and after operation. The incidences of both MEP/SEP improvement and deterioration were similar between the two laminectomy groups (P > 0.05), and no significant difference is noted in both MEP and SEP amplitudes between the baseline and different critical manipulations in both laminectomy groups (P > 0.05). In the improvement group, patients receiving en bloc laminectomy exhibited increased improvement rates of both MEPs in bilateral AH and left-side SEPs compared to piecemeal laminectomy (P < 0.05). Clinically, all functional scales clearly improved in both laminectomy groups after operation (P < 0.05), and postoperative 1-year mJOA improvement rates were highly correlated with MEP improvement rates (P < 0.05). Intraoperative changes of MEPs and SEPs potentially provide a valid method for quantitatively evaluating the safety of different intraoperative manipulations and their prognostic impacts on spinal cord. Both laminectomies are safe and effective methods to treat TOLF, and en bloc laminectomy may cause relatively better spinal cord functional recovery.Level of Evidence: 3.