Intraoperative Quality Control Research Articles

Evidence-based Guidelines for Keratorefractive Lenticule Extraction Surgery

Development of evidence-based guidelines for keratorefractive lenticule extraction (KLEx). KLEx refers to various corneal refractive procedures involving removal of refractive lenticules of intrastromal corneal tissue, typically through a small incision, thereby eliminating creation of a corneal flap. This technique has rapidly gained popularity as a possible alternative to flap-based procedures; however, no clinical practice guidelines exist for KLEx. These evidence-based guidelines were developed following the WHO guidebook, utilizing the AGREE II tool, and adhering to the RIGHT statement. The body of evidence was drawn from eight literature databases, five clinical guideline databases, and two academic organizations. Recommendations were developed via a Delphi consensus of 44 global experts in refractive surgery, corneal diseases, retinal diseases, glaucoma, and optometry. The certainty of evidence, balance of benefits and harms, patient preferences and values, and economic evaluations were fully considered. The GRADE approach was employed to assess evidence quality and recommendation strengths. From 385 initial clinical questions, 15 were identified, prompting a review of 250,717 studies, with 609 included for conducting and updating 26 and 2 systematic reviews, respectively. Subsequently, consensus was reached on 38 recommendations for preoperative screening, candidate selection, intraoperative quality control, operating principles, postoperative monitoring, and complication management. For KLEx, an effective and accurate refractive correction is attributed to various factors such as corneal thickness, degree of myopia, treatment nomogram, and optical zone. For KLEx-related complications that could affect vision, comprehensive and effective management strategies were proposed, particularly for wrong-plane dissection and difficult lenticule removal, suction loss, and perioperative infection. Customized surgical planning protocols and operative techniques were analyzed. Among all recommendations, 29 (76%) were labelled as "strong", each externally reviewed. The assessment of corneal biomechanical properties may help improve safety and predictability, though needing further validation. The development process also revealed several research gaps for enhancing KLEx safety. These guidelines provide evidence-based recommendations for KLEx in clinical practice, such as on preoperative screening for keratoconus, surgical planning, managements and prevention of complications and infection. The guidelines are expected to improve the safe and effective application of KLEx procedures and achieve more satisfactory visual correction.

Three-Dimensional Heart Modeling of Hypertrophic Obstructive Cardiomyopathy for In Situ Patient-Specific Simulation to Optimize Septal Myectomy.

Hypertrophic obstructive cardiomyopathy (HOCM) develops in at least 1 out of 715 young adults. Patients who are refractory to medical therapy qualify for septal myectomy. Due to anatomy, serious complications such as ventricular septal defect and heart block may occur. Establishing cardiovascular magnetic resonance (CMR)-based 3-dimensional (3D) models as part of preoperative planning and training has the potential to decrease procedure-related complications and improve results. CMR images were used to segment cardiac structures. Left ventricular wall thickness was calculated and projected on top of the in silico model. A 3D model was printed with a red layer indicating a wall thickness exceeding 15 mm and used for preoperative resection planning and patient counseling. To provide preoperative patient-specific in situ simulation, the planned resection volume was replaced with silicone in a second model. For perioperative quality control, resected silicone was compared with resected myocardial tissue. The impact of the models was evaluated descriptively through consultation of both the cardiothoracic surgeon and patients and through patient outcomes. Three-dimensional in silico and 3D-printed heart models of 5 patients were established preoperatively. Since the introduction of the models in October 2020, the surgeon feels better prepared, more confident, and less difficulty with making decisions. In addition, patients feel better informed preoperatively. Using 3D heart models optimized preoperative planning and training, intraoperative quality control, and patient consultation. Reduction of procedure-related complications and clinical outcome should be studied in larger cohorts.

Detection of wound healing disorders after major amputations by measurements of the microcirculation: A prospective single-center study.

Although major amputations can often be avoided due to evolving methods of endovascular and surgical revascularizations techniques, in patients with chronic limb-threatening ischemia, it is still necessary in some cases. Aim of this study was the detection of wound healing disorders through intraoperative microcirculation measurements in major limb amputations. In this single-center clinical study, patients with an indication for major amputation were enrolled prospectively. Cause of amputation, patients' comorbidities including cardiovascular risk profile were assessed. Macrocirculation, as well as microcirculation were assessed. Microcirculation measurements were performed by fluorescence angiography with the administration of indocyanine green. A preoperative measurement was obtained at the amputation level, followed by three additional measurements of the amputation stump postoperatively. Wound healing was monitored and correlated with the microcirculatory findings, based on the perfusion parameters ingress and ingress rate, calculated in the indocyanine green fluorescence video sequences of the amputation stumps. Forty-five patients were enrolled, including 19 (42%) below-the-knee amputations and 26 (58%) above-the-knee amputations. When considering the need for revision, a change in the microperfusion parameters was observed postoperatively. The mean value for ingress was significantly lower directly postoperatively in stumps requiring revisions (5 ± 0 A.U. versus 40.5 ± 42.5 A.U., p < 0.001). The mean value of ingress rate behaved similarly (0.15 ± 0.07 A.U./s versus 2.8 ± 5.0 A.U./s, p = 0.005). The evaluation of indocyanine green measurements when wound healing disorders occurred also showed nonsignificant differences in the mean values. Fluorescence angiography after major lower limb amputations appears to be an option of depicting microperfusion. Especially, the early postoperative detection of reduced perfusion can indicate a subsequent need for revision. Therefore, this method could possibly serve as a tool for intraoperative quality control after major limb amputation.

Sutures positioning technique enhances the predictability and concordance between preoperative simulation and actual outcomes in rhinoplasty

The predictability and concordance between simulated and actual outcomes in rhinoplasty are uncertain. Here, we introduce a suture positioning technique (SPT), a simple and low-cost method to minimize the gap between the simulated and actual outcomes of rhinoplasty. Seventy patients were enrolled in this study between January 2018 and January 2021. Preoperative simulations were performed using Adobe Photoshop. The control group underwent surgery using simulation and intuition. In the SPT group, sutures were used to assist in the preoperative identification of the ideal nasal tip position. The SPT effectiveness was tested by measuring the nasal parameters and using the patient's subjective satisfaction questionnaire at T1 (Time 1, immediately postoperatively) and T2 (Time 2, at least 1 year postoperatively). The intraclass correlation coefficient test showed a satisfactory correlation between simulation and postoperative outcomes in both groups. However, the SPT group had a higher correlation than the control group, especially for the nasal length (16% higher at T1 and 15% higher at T2). The mean absolute difference (MAD) between the outcomes and simulation indicated that the MAD of nasal tip projection between T2 and simulation and MAD of nasal length between T1 (or T2) and simulation were statistically significant between groups. Additionally, the SPT group was more satisfied with the postoperative outcomes and were consistent with the preoperative simulation. This study demonstrated the effectiveness of SPT in intraoperative quality control. This technique may be adopted by surgeons to achieve good concordance between simulated and actual surgical outcomes.

Impact of acute coronary graft failure and subsequent urgent endovascular revascularization after planned coronary artery bypass grafting on hospital outcome

Highlights The authors conducted a comparative analysis of early postoperative complications, mortality and economic costs in patients who underwent additional urgent endovascular revascularization and patients with standard postoperative period.There are statistically significant differences between the groups in terms of the number of resternotomies performed, the need for transfusable blood components and economic costs.It is necessary to introduce routine intraoperative quality control of the intervention, and a set of measures aimed at early detection of coronary graft failure in real clinical practice. Abstract Aim. To assess the impact of coronary graft failure and subsequent urgent endovascular revascularization in the early postoperative period after elective coronary artery bypass grafting on hospital outcome.Materials and methods. 8801 patients underwent isolated coronary artery bypass grafting at the Federal State Budgetary Institution “Federal Center for Cardiovascular Surgery” of the Ministry of Health of the Russian Federation in Chelyabinsk from 2011 to 2020. Inclusion criteria were as follows: patients with stable coronary heart disease, patients undergoing elective coronary artery bypass grafting. Exclusion criteria were as follows: patients with unstable angina and acute myocardial infarction who underwent urgent revascularization. The primary endpoint was hospital mortality, secondary endpoints are bleeding requiring resternotomy, acute abdominal and infectious complications, and multiple organ failure. Due to suspected acute myocardial injury, 196 (2.23%) patients underwent urgent coronary angiography, and according to angiogram, additional endovascular correction was performed in 60 (0.68%) patients (the group I). To assess the impact of coronary graft failure and subsequent revascularization on hospital outcome we have analyzed: hospital mortality, complications in the early postoperative period, financial costs. Moreover, we have formed the group II of 60 people with uncomplicated postoperative period for comparative analysis.Results. Of 196 (2.23%) patients who underwent urgent angiography 60 (0.68%) patients required stenting of native coronary arteries or conduits due to coronary graft failure. Hospital mortality in the group with complicated postoperative period was 10 % (6 cases), hemorrhagic complications occurred in 13 (21.7%) patients, acute abdomen was noted in 4 patients, and sternal wound infection was noted in 5 patients, hemodialysis due to multiple organ failure was performed in 5 patients. An intergroup comparative analysis revealed a clear trend towards an increase in deaths in the group I (n = 6/10%) compared to the group II (n = 1/1.7%), however, there were no significant differences (p = 0.11F). Hemorrhagic complications occurred significantly higher in group I (13/21.7% versus 1/1.7%, p = 0.001F); there were no statistically significant differences associated with the other complications. The number of bed-days spent in the hospital and in the intensive care unit was statistically significantly higher in the group I, financial costs per patient were also significantly higher in the group I.Conclusion. Coronary bypass graft failure in the early postoperative period leads to an increase in hospital mortality, in the frequency of multiple organ failure and hemorrhagic complications, and significantly increases the amount of needed economic resources.

Locoregional Anaesthesia and Intra-Operative Angiography in Carotid Endarterectomy: 16 Year Results of a Consecutive Single Centre Series

The benefit of local (LA) over general (GA) anaesthesia and the rationale of intra-operative imaging strategies during carotid endarterectomy (CEA) is debated. This study analysed the associations between patient characteristics, LA, and intra-operative imaging strategies and the in hospital stroke and death rates in elective CEA over a 16 year period. All consecutive patients treated by elective CEA between January 2004 and December 2019 (n= 1 872; median age 71 years, 70% male, 37% symptomatic) were included. All patients were assessed neurologically before and within 48 hours after CEA. The primary outcome event was the combined rate of any in hospital stroke or death. Secondary outcome events were the combined rates of any in hospital major stroke (modified Rankin scale [mRS] 3 - 5) or death, stroke, minor stroke (mRS 0 - 2), major stroke, and death alone. To detect changes over time, four quartiles (2004 - 2007, 2008 - 2011, 2012 - 2015, and 2016 - 2019) of this cohort were analysed. Statistical analysis comprised trend tests, and uni- and multivariable logistic regression. Median patient age increased from 68 to 73 years (p < .001). Over time, LA (from 28% to 91%) and intra-operative imaging (angiography 2.8 - 98.1%, duplex ultrasound 0 - 78.2%) was applied more frequently. Surgical techniques did not change. The in hospital stroke or death and major stroke or death rates decreased from 3.7% to 1.5% (p= .041) and from 2.8% to 0.9% (p= .014), respectively, corresponding to a relative risk of decline of 7% and 12% annually. Multivariable analysis revealed that LA (odds ratio [OR] 0.25, 95% confidence interval [CI] 0.1 - 0.62) and intra-operative angiography (OR 0.09, 95% CI 0.10 - 0.81) were associated with lower in hospital major stroke and death rates. These data demonstrate a decline in the combined rates of any in hospital major stroke or death after non-emergency CEA over time. Locoregional anaesthesia and intra-operative quality control were associated with these improvements and might be worthwhile in elective CEA.

Effect of routine intracerebral completion angiography on outcomes after transcarotid artery revascularization

ObjectiveCompletion cerebral angiography (CCA) after transcarotid artery revascularization (TCAR) has been used to identify distal embolization after stenting and serve as a measure of intraoperative quality control. Nevertheless, no general evidence has been reported regarding the benefit of performing routine CCA. The aim of the present study was to evaluate the potential risks and benefits of routine CCA. MethodsWe retrospectively reviewed the Vascular Quality Initiative database for TCAR from 2016 to 2021. The patients were divided into two groups: those with no CCA performed and those with CCA performed. The primary outcome was in-hospital stroke or death. The secondary outcomes included stroke, death, myocardial infarction, and a return to the operating room (RTOR). Clinically relevant and statistically significantly variables on univariable analysis were added to a logistic regression model clustered by center identifier. ResultsA total of 18,155 patients who had undergone TCAR were identified, of whom 11,607 (63.7%) had undergone routine CCA. The patients with routine CCA were more likely to have contralateral carotid occlusion and to have received general anesthesia. After adjusting for potential confounders, we found no differences in the risk of stroke/death (adjusted odds ratio [aOR], 1.03; 95% confidence interval [CI], 0.8-1.3; P = .820), stroke/transient ischemic attack (TIA; aOR, 1.00; 95% CI, 0.8-1.3; P = .998), stroke (aOR, 1.1; 95% CI, 0.8-1.4; P = .452), death (aOR, 0.98; 95% CI, 0.6-1.6; P = .953), myocardial infarction (aOR, 0.78; 95% CI, 0.5-1.2; P = .240), or RTOR (aOR, 1.5; 95% CI, 0.6-3.8; P = .412) between patients who had undergone CCA and those who had not. A subanalysis of the patients with new occlusions detected by CCA (69 patients [0.6%]; 19 not treated and 50 treated) indicated a higher risk of stroke/death for the patients with treated new occlusions (aOR, 7.1; 95% CI, 2.9-17.3; P < .001) and stroke/TIA (aOR, 5.8; 95% CI, 2.3-14.7; P < .001) than for the patients who had not undergone CCA. However, no differences were found in stroke/death (aOR, 3.3; 95% CI, 0.37-29.5; P = .283) or stroke/TIA (aOR, 3.1; 95% CI, 0.3-29.4; P = .327) for patients with nontreated new occlusions compared with patients who had not undergone CCA. ConclusionsIn the present retrospective study, routine performance of CCA was not beneficial, with no significant differences in in-hospital stroke or death detected. The detection of new lesions on CCA was rare. Moreover, identifying new occlusions using CCA was associated with higher odds of stroke or death when these new lesions were treated. Further studies are needed to define the etiology of the worse outcomes for patients undergoing intervention for lesions discovered using CCA and delineate the optimal timing for further imaging and intervention.

Stimulated Raman histology in the neurosurgical workflow of a major European neurosurgical center \u2014 part A

Histopathological diagnosis is the current standard for the classification of brain and spine tumors. Raman spectroscopy has been reported to allow fast and easy intraoperative tissue analysis. Here, we report data on the intraoperative implementation of a stimulated Raman histology (SRH) as an innovative strategy offering intraoperative near real-time histopathological analysis. A total of 429 SRH images from 108 patients were generated and analyzed by using a Raman imaging system (Invenio Imaging Inc.). We aimed at establishing a dedicated workflow for SRH serving as an intraoperative diagnostic, research, and quality control tool in the neurosurgical operating room (OR). First experiences with this novel imaging modality were reported and analyzed suggesting process optimization regarding tissue collection, preparation, and imaging. The Raman imaging system was rapidly integrated into the surgical workflow of a large neurosurgical center. Within a few minutes of connecting the device, the first high-quality images could be acquired in a “plug-and-play” manner. We did not encounter relevant obstacles and the learning curve was steep. However, certain prerequisites regarding quality and acquisition of tissue samples, data processing and interpretation, and high throughput adaptions must be considered. Intraoperative SRH can easily be integrated into the workflow of neurosurgical tumor resection. Considering few process optimizations that can be implemented rapidly, high-quality images can be obtained near real time. Hence, we propose SRH as a complementary tool for the diagnosis of tumor entity, analysis of tumor infiltration zones, online quality and safety control and as a research tool in the neurosurgical OR.

Effect of Routine Completion Angiography on Outcomes After Transcarotid Artery Revascularization

Completion angiography after transcarotid artery revascularization (TCAR) is performed to achieve intraoperative quality control by identifying distal embolization after stenting. Nonetheless, no general evidence is available regarding the benefit of performing routine completion angiography. The aim of the present study was to evaluate the potential risks and benefits of routine intracranial completion angiography.

Tracking heart surface features to determine myocardial contrast agent enrichment

Abstract Fluorescent cardiac imaging can be applied for intraoperative quality control after a coronary bypass grafting surgery to ensure the myocardial perfusion by evaluating the increasing contrast agent enrichment in the heart. The motion due to the beating heart impedes the interpretation of the contrast agent enrichment in the vessels and leads to noisy enrichment curves. We propose tracking of the heart surface features to compensate for the motion of the beating heart and thereby improve the analysis of the contrast agent enrichment. Furthermore, we propose a vessel segmentation pipeline for a local evaluation of contrast agent enrichment directly in the vessels.

Self-centering second-generation patient-specific functionalized implants for deep orbital reconstruction

Deep and complete reconstruction of the orbital cavity has been shown to be essential for preventing enophthalmos and hypoglobus in patients with orbital defects or deformities. Additively manufactured patient-specific titanium implants provide unlimited options in design. However, implant malpositioning can still occur, even when intraoperative imaging and navigation are used. In this study, we investigated novel orbital implants containing features facilitating self-centering.Accuracy of implant placement and reconstruction of the orbital dimensions were compared retrospectively between self-centering second-generation patient-specific functionalized orbital implants (study group) and CAD-based individualized implants (control group). Design features of implants in the study group included functionalization with navigation tracks, a preventive design, and flanges - so called stabilizers - towards opposite orbital walls. Implant position was evaluated by fusion of preoperative virtual plans and the post-therapeutic imaging. Aberrances were quantified by 3D heatmap analysis.31 patients were assigned to the study group and 50 to the control group, respectively. In the study group, most implants were designed with either one (n = 18, 58.06%) or two (n = 10, 32.26%) stabilizers. Twice (6.45%), one stabilizer had to be shortened intraoperatively. Implant fit analysis revealed a significantly more precise (p < 0.001) positioning in the study group (n = 22/31) than in the control group (n = 42/50).Self-centering second-generation patient-specific functionalized orbital implants showed significantly more accurate implant positioning, facilitating the transformation of virtual plans into patient’s anatomy. The presented design provides an additional instrument for intraoperative quality control besides intraoperative imaging and navigation.

Patient and haemodynamic factors affecting intraoperative graft flow during coronary artery bypass grafting: an observational pilot study

Transit-time flow measurement (TTFM) is frequently used to evaluate intraoperative quality control during coronary artery bypass grafting (CABG) and has the ability to assess graft failure intraoperatively. However, perioperative factors affecting TTFM during CABG remain poorly understood. Patients who underwent CABG at a single institution between July 2016 and May 2018 were prospectively evaluated. TTFM and blood viscosity were measured haemodynamically, while mean flow (mL/min), pulsatility index, and diastolic filling were recorded. Arterial blood gas was analysed immediately after left internal mammary artery to left descending artery anastomosis and before sternal closure. Factors associated with TTFM were assessed using multiple linear regression analysis. We evaluated 57 of the 62 patients who underwent CABG during the study period, including 49 who underwent off-pump and 8 who underwent on-pump surgeries. Blood viscosity was not significantly associated with TTFM (p > 0.05). However, TTFM was significantly associated with body mass index, systolic blood pressure, and cardiac index (p < 0.05 each). In conclusion, maintaining the SBP in the perioperative period and maintaining the CI with inotropic support or fluid resuscitation can be important in improving blood flow of graft vessels after surgery.

Completion imaging techniques and their clinical role after carotid endarterectomy: Systematic review of the literature.

Completion imaging has been suggested for the intraoperative quality control assessment of the carotid endarterectomy technical success, in order to immediately resolve pathologic findings and accordingly improve patients' outcome. The aim of this study was to present existing evidence of different completion imaging techniques after carotid endarterectomy and their role on clinical outcome. A systematic review was performed searching in MEDLINE, CENTRAL, and Cochrane databases including studies reporting on completion imaging techniques after carotid endarterectomy. A total of 12,378 patients in 35 studies (20 retrospective and 15 prospective) underwent a completion imaging technique after carotid endarterectomy: in 19 studies, 5340 patients underwent arteriography; in 5 studies, 2095 angioscopy; in 21 studies, 5722 DUS; and in 2 studies, 150 patients underwent transcranial Doppler. Ten studies assessed > 1 imaging technique. The mean age was 67 ± 7 years old (69% males) with common co-morbidities to be hypertension (74%), smoking (64%), and hyperlipidemia (54%). Almost half of the patients (4949; 44%) were treated for symptomatic disease. In 1104 (9.7%) patients, a major defect was identified intra-operatively, while in 329 patients (2.9%), a minor defect. Common pathological findings were the presence of mural thrombus, carotid dissection, residual stenosis, and intimal flaps. An immediate re-intervention was undertaken in 75% (790/1053) of the patients to treat a major intra-operative imaging finding. In patients with re-intervention, only 2.3% (14/609) had an intra-operative stroke and 0.8% (5/609), a transient ischemic attack, while only 1.4% (8/575) had a stroke and 0.2% a transient ischemic attack (1/575) during 30-day post-operative period. No intra-operative death was reported. In the same period, the restenosis rate of internal and common carotid artery was 0.5% (3/575) and 0.2% (1/575), respectively. Completion imaging techniques can detect defects in almost 10% of patients that may lead to immediate intra-operative surgical revision with low intra-operative stroke/transient ischemic attack rate and low early carotid restenosis. During the 30-day follow-up period, in those patients, the incidence of stroke/transient ischemic attack may be low but present. This review cannot provide any evidence on which completion imaging technique is better, and the clinical impact conferred by each technique in the absence of a randomized control studies.

Онкологическая безопасность нервосберегающей техники радикальной простатэктомии: оценка патоморфологических результатов и безрецидивной выживаемости

To evaluate histopathological outcomes and biochemical recurrence (BCR) free survival in patients after nerve-sparing radical prostatectomy (nsRP). Prospective study group comprised 313 patients who underwent uni- or bilateral nsRP from 2014 to 2018; control group included 592 patients with clinically localized prostate cancer who underwent non-nsRP from 2014 to 2018. Mann-Whitney U-test was performed to assess continuous variables; chi-squared test was used for comparative analysis of categorical data. BCR free survival was evaluated with Kaplan-Meier method, log-rank test was used to compare survival outcomes. Adverse histopathological findings were lower in the study group: extracapsular extension was found in 9,4% and 18,75% (p<0,001), grade group upgrade in 23% and 29,3% (p=0,04), positive surgical margins (PSM) in 15% and 22,1% (p=0,01). Subanalysis according to cancer risk groups showed lower PSM rates in high-risk patients (15,6% and 30,3%, p=0,017) and tendency for higher PSM rates in low-risk patients in the study group with no significant difference (12,6% and 7%, p=0,16). BCR free survival after 12 months was 100% and 88,2%, after 20 months - 92,3% and 86,4%, p=0,04. PSM ratesin the study group were notsignificantly different depending on the type of surgery: 13,9% in robotic-assisted approach and 15,4% in retropubic approach, p=0,75. Relatively favorable histopathological outcomes and BCR free survival can be achieved after nsRP. However, obtained results could not be considered optimal and clearly indicate the need for further improvement of preoperative planning and intraoperative quality control of surgical treatment.

Changes in Carotid Surgery Over One Decade: Lower Mortality and Morbidity Associated with Intra Operative Quality Control and Refinement of Technique Despite Increased Octogenarian Operations

Changes in Carotid Surgery Over One Decade: Lower Mortality and Morbidity Associated with Intra Operative Quality Control and Refinement of Technique Despite Increased Octogenarian Operations

Do Not Forget to Pull the Graft!

A 71 year old woman presented with a two month history of left lower limb claudication. Her history included an above knee femoropopliteal bypass using a 7 mm heparin bonded expanded polytetrafluoroethylene graft (Propaten, WL Gore & Associates, Flagstaff, USA) six months previously for critical limb ischaemia (rest pain). Computed tomography angiography revealed a thrombosed graft, severely kinked where it lay beneath sartorius (A and B). Lack of appropriate intra-operative graft pulling and straightening probably caused the problem. This case illustrates the importance of intraoperative quality control after bypass surgery to prevent kinks or other problems that might hinder flow and predispose to occlusion.Image 1

Invited commentary

With 827 consecutive post-carotid endarterectomy completion arteriograms, Dr Wieker and colleagues detected 57 (6.9%) defects requiring immediate surgical revision. One in 14 of their cases required reopening of the artery! Despite their significant incidence of defects requiring immediate revision, the authors' overall results are superb (0.2%, 0.5%, and 0.6% 30-day mortality, stroke, and transient ischemic attack rates, respectively), and immediate revision was not associated with worse outcomes. Should we adopt the authors' recommendation to perform completion arteriography after all carotid endarterectomies? Before adopting routine completion angiography in our practices, we should answer three questions. First, can we standardize criteria for arterial re-exploration? The authors' figures demonstrate egregious findings clearly requiring re-exploration, but what about more subtle findings? Second, are there less invasive, less time-consuming, and equally accurate methods for assessing the adequacy of reconstruction? Continuous-wave Doppler interrogation, duplex ultrasound, prearterial closure angioscopy, and electromagnetic flow measurements have all been reported to be effective in detecting thrombus, flaps, and other defects requiring revision. There are no data consistently demonstrating the superiority of routine completion angiography over these methods. Third, does every patient need the same completion study? Does the “easy” endarterectomy (thin mobile neck, low bifurcation, focal plaque, easily visualized perfect end point) require the same completion study as the difficult endarterectomy? Perhaps we can use one modality, such as continuous-wave Doppler, for the straightforward cases and reserve arteriography or duplex ultrasound for the more difficult cases and for those with less than perfect Doppler findings. Because so many surgeons have reported excellent results (comparable to the authors') without performing routine completion arteriography, I find it hard to accept the authors' recommendation. There are, however, a few essential routines. The first is obsessive attention to detail in the performance of carotid endarterectomy, both in creation of the endarterectomy end point and in optimizing flow across the fresh, thrombogenic endarterectomy surface. This requires excellent exposure with clear visualization of the arterial intima distal to the plaque and occasional use of tacking sutures or plication techniques. In addition, any anatomic feature that results in damped flow or high resistance to flow, such as proximal common carotid lesions or distal internal carotid kinks, must be treated. Similarly, obsessive attention to perioperative and intraoperative medical management (aspirin, statins, appropriate heparin dosing, tight blood pressure control) is a prerequisite for superior outcomes. Finally, as alarmingly demonstrated in this study, even when experienced surgeons employ standardized, state-of-the-art techniques, anatomic outcomes can be poor. For this reason, routine intraoperative completion studies are essential. For the authors, routine completion arteriography has proven safe and effective. However, there are many other options for intraoperative quality control. In the absence of compelling data supporting the superiority of any one technique, each surgeon should continue to use what works best for her or him while carefully monitoring outcomes and exploring every opportunity for improvement. Impact of routine completion angiography on outcome after carotid endarterectomyJournal of Vascular SurgeryVol. 69Issue 3PreviewThe objective of this study was to analyze the impact of completion digital subtraction angiography (cDSA) after carotid endarterectomy (CEA) on technical and early clinical results. Full-Text PDF Open Archive

Implementation of Intraoperative Computed Tomography for Deep Brain Stimulation: Pitfalls and Optimization of Workflow, Accuracy, and Radiation Exposure

Deep brain stimulation (DBS) is an effective treatment for movement disorders. Stereotactic electrode placement can be guided by intraoperative imaging, which also allows for immediate intraoperative quality control. This article is about implementation and refining a workflow applying intraoperative computed tomography (iCT) for DBS. Eighteen patients underwent DBS with bilateral implantation of directional electrodes applying a 32-slice movable computed tomography scanner in combination with microelectrode recording. iCT led to a significant decrease in overall procedural time, despite performing multiple scans. In 3 of the initial 5 cases, iCT caused an adjustment of the final electrodes demonstrating the learning curve and the necessity to integrate road mapping for the exchange of microelectrode to final electrode. Implementation of low-dose computed tomography protocols added microelectrode iCT to the refined workflow, resulting in an intraoperative adjustment of a trajectory in 1 patient. Low-dose protocols lowered the total effective dose to 1.15 mSv, that is, a reduction by a factor of 3.5 compared to a standard non-iCT DBS procedure, despite repeated iCTs. Intraoperative lead detection based on final iCT revealed a radial error of 1.04 ± 0.58 mm and a vector error of 2.28 ± 0.97 mm compared to the preoperative planning, adjusted by the findings of microelectrode recording. iCT can be easily integrated into the surgical workflow resulting in an overall efficient time-saving procedure. Repeated intraoperative scanning ensures reliable electrode placement, although low-dose scanning protocols prevent extensive radiation exposure. iCT of microelectrodes is feasible and led to the adjustment of 1 electrode.

Intraoperative quality control with transit time flow measurement

Vascular reconstructions carry a high risk of early and late failure, leading potentially to major problems. Therefore, it is crucial to ensure the quality of reconstructions at the end of every operation. No method has been shown to be superior to others and it is beneficial for the vascular surgeons to master many techniques. Transit time flow measurement (TTFM) is a fast and easy way to directly evaluate the desired end result; blood flow to the end organ. It is not problem-free nor totally reliable. In addition to TTFM different quality control methods including their pros and cons are discussed.

A Cadaveric Comparative Study on the Surgical Accuracy of Freehand, Computer Navigation, and Patient-Specific Instruments in Joint-Preserving Bone Tumor Resections.

Orthopedic oncologic surgery requires preservation of a functioning limb at the essence of achieving safe margins. With most bone sarcomas arising from the metaphyseal region, in close proximity to joints, joint-salvage surgery can be challenging. Intraoperative guidance techniques like computer-assisted surgery (CAS) and patient-specific instrumentation (PSI) could assist in achieving higher surgical accuracy. This study investigates the surgical accuracy of freehand, CAS- and PSI-assisted joint-preserving tumor resections and tests whether integration of CAS with PSI (CAS + PSI) can further improve accuracy. CT scans of 16 simulated tumors around the knee in four human cadavers were performed and imported into engineering software (MIMICS) for 3D planning of multiplanar joint-preserving resections. The planned resections were transferred to the navigation system and/or used for PSI design. Location accuracy (LA), entry and exit points of all 56 planes, and resection time were measured by postprocedural CT. Both CAS + PSI- and PSI-assisted techniques could reproduce planned resections with a mean LA of less than 2 mm. There was no statistical difference in LA between CAS + PSI and PSI resections (p=0.92), but both CAS + PSI and PSI showed a significantly higher LA compared to CAS (p=0.042 and p=0.034, respectively). PSI-assisted resections were faster compared to CAS + PSI (p < 0.001) and CAS (p < 0.001). Adding CAS to PSI did improve the exit points, however not significantly. In conclusion, PSI showed the best overall surgical accuracy and is fastest and easy to use. CAS could be used as an intraoperative quality control tool for PSI, and integration of CAS with PSI is possible but did not improve surgical accuracy. Both CAS and PSI seem complementary in improving surgical accuracy and are not mutually exclusive. Image-based techniques like CAS and PSI are superior over freehand resection. Surgeons should choose the technique most suitable based on the patient and tumor specifics.