Can Loupe magnification be a viable alternative to Operative Microscope magnification for vascular anastomosis in reconstructive surgery? A systematic review and meta-analysis

PURPOSE

The aim of this study is to compare the outcomes of vascular anastomosis using loupes magnification versus operative microscope magnification in reconstructive surgery.

METHODS

We performed a systematic review of MEDLINE (via PubMed), Scopus and Cochrane Library database according to the PRISMA guidelines. Comparative studies between the two techniques and single arm studies reporting on loupes reconstruction were included. Random-effects model meta-analyses were performed.

RESULTS

Twelve studies, reporting a total of 3908 of flaps, 3409 of which were performed under loupes magnification and 499 under the operative microscope magnification were selected for analysis. No statistically significant differences were observed regarding total flap loss and vascular complication between the two arms. In the Loupes group the rate of total flap loss was 2.65% (95% CI: 1.15-4.63) and the rate of vascular complications 4.49% (95% CI: 2.58-6.84).

CONCLUSION

Loupes magnification under circumstances can provide a safe and effective alternative to microvascular reconstruction in reconstructive surgery. With respect to flap failure and vascular complication rates, there appear to be no statistically significant differences between the anastomoses conducted under Loupes magnification and the standard operative microscope.

Role of Loupes Magnification in Tracheal Resection and Anastomosis

Tracheal resection and anastomosis is characterized in the last years by significant innovations which are well codified and standardized. Although the mortality rate is markedly reduced, the operation is still not free from risk of complications such as recurrent laryngeal nerve injury, anastomosis dehiscence, granulation tissue formation and restenosis. Pearson FG, Cooper ID, Nelems JL (1975) Primary tracheal anastomosis after resection of the cricoide cartilage with preservation of the recurrent laryngeal nerves. J Thorac Cardiovasc Surg 70:806-16.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12070-023-04115-3.

Comparing Thyroidectomy Techniques, Surgical Loupe and Neuromonitoring Between ENT and Endocrine Surgeons-an Observational Study

Thyroid surgery is performed by ENT head and neck (ENT-HNS), endocrine (ES) and general surgeons (GS). Each modality adopts different surgical techniques causing difference in outcome, operative time and postoperative complication. A retrospective chart review of thyroid surgeries performed by two ENT-HNS, three ES of a single tertiary center was conducted. We compared the use of neuromonitoring and surgical loupe and subsequent patient outcomes between surgeries performed by ENT-HNS versus ES, focusing on parathyroid gland identification, operative duration, vocal cord paralysis and length of hospital stay. A total of 167 patients underwent thyroid surgery. Surgical loupes were used in all the surgeries performed by ENT-HNS vs. 85% by the ES. Parathyroid glands were identified in all the surgeries performed by ENT-HNS versus 95% by ES. Neuromonitoring was used in all the surgeries performed by ENT-HNS, and none by the ES. Vocal cord paralysis developed in two patients of ES versus none in the ENT-HNS. Mean operative duration for total thyroidectomy in ENT-HN surgeries, 183.7 min vs. 151 min in the ES. The mean hospital stay of patients was 3.6 ± 1.6 days for ENT-HNS, and 5.45 ± 3 days for ES. Identification of parathyroid gland and recurrent laryngeal nerve by neuromonitoring and surgical loupes may increase operative time but decrease the rate of vocal cord paralysis and increases the chance of parathyroid gland identification.

Surgeon's Eyes on the Relevant Surgical Target

The resolution of the naked eye has been a challenge for the neurosurgical endeavor since the very first attempts of cranial surgery, and advances have been achieved over the centuries, driven by a synergism between the application of emerging technology into the surgical environment and the expansion of the capabilities of neurosurgery. The understanding of the principles of the optical properties of lenses by Abbè (1840-1905) led to the introduction of loupes in the surgical practice, increasing the visual performance during macroscopic procedures. Modern neurosurgery began with the possibility of illumination and magnification of the surgical field as provided by the microscope. Pioneering contributions from Donaghy and Yasargil opened the way to the era of minimalism with reduction of operative corridors and surgical trauma through the adoption of the microsurgical technique. Almost at the same time, engineering mirabilia of Hopkins in terms of optics and lenses allowed for introduction of rigid and flexible endoscopes as a viable tool in neurosurgery. Nowadays, neurosurgeons are aware of and confident using effective and modern tools of visualization in their armamentarium. Herein we present a cogent review of the evolution of visualization tools in neurosurgery, with a special glimpse into the current development and future achievements.

External validation of a low fidelity dry-lab platform to enhance loupes surgical skills techniques for hypospadias repair

INTRODUCTION

Hypospadias repair is an index pediatric urology procedure that requires trainee familiarity with surgical loupes. A previous low-fidelity, 6-step curriculum was proposed that deconstructed the most important steps of loupe surgery. We expanded on this curriculum with an intermediate-fidelity silicone hypospadias model and designed an abbreviated version of the 6-step curriculum to precede the hypospadias repair simulation.

OBJECTIVE

To assess the validity of our prior, low-fidelity conceptual model using the metric of improved performance on the intermediate-fidelity silicone hypospadias model.

STUDY DESIGN

A silicone model was first prototyped with the design software Solidworks™, and then fabricated using a cast made of a mixture of silicone rubbers designed to function like skin and soft tissue (Mold Star 20T, Dragon skin FX-pro and Slacker). Casts were used to create the penile shaft model and the dorsal hooded foreskin model. The urethral plate was cast separately on a flat surface. The model was then assembled by hand. The model used for simulation included the penile shaft and urethral plate, while the dorsal-hooded foreskin was prepared to simulate the penile anatomy separately. Trainees were then divided into two groups. Group 1 practiced the low-fidelity curriculum (3 tasks) and then performed dissection of the urethral plate and suturing using the intermediate-fidelity hypospadias model. Group 2 practiced hypospadias repair prior to the low-fidelity curriculum. Both groups' models were scored by 3 blinded urologists. Trainees were then asked to complete a post simulation satisfaction survey. Data analysis was performed in IBM SPSS Statistics for Macintosh (Version 28.0 Armonk, NY: IBM Corp).

RESULTS

Twenty-two candidates across Wisconsin, USA, and Dublin, Ireland participated in the study. This included 7 s-year residents, 9 third-year residents, 2 fourth-year residents, and 3 fifth-year residents. Both Groups 1 and 2 had a similar distribution of trainees (p = 0.60). Group 1 outperformed group 2 in all tasks (p < 0.05, Table 1). Trainees reported that the platform was very useful (91%).

DISCUSSION

Our curriculum showed improvement in trainee ability and comfort to perform hypospadias repair. Advantages of such a simulated curriculum include improving current resident training in microsurgery, improving surgical ergonomics for trainees prior to real-time experience, and decreasing the learning curve for trainees pursuing pediatric urology.

CONCLUSION

An intermediate-fidelity hypospadias platform externally validates the conceptual model implemented in the low-fidelity loupes curriculum. This appears to lead to improvement in loupe surgical skills regardless of trainee level.

Characteristics and attitudes of general and pediatric dentists who use loupes

BACKGROUND

Dental loupes are used by dental professionals to improve visual performance, reduce eye strain and prevent musculoskeletal disorders. Data on their usage in pediatric dentistry are scarce.

STUDY DESIGN

We performed a cross-sectional survey to evaluate the approach, knowledge, and frequency of using loupes among 100 general and pediatric dentists.

RESULTS

showed that the use of loupes is significantly more prevalent among general dentists (64.3%) compared to pediatric specialists and residents (35.7%). Among dentists who reported that they do not use loupes, 63.6% were pediatric dentists and residents, and 82.5% were dentists working with children. A significantly higher percentage of dentists who self-reported as loupes users perceived that the loupes afford comfortable and stable posture, confidence while working, and contribute to the detection of tooth decay. A significantly higher percentage of dentists who self-reported as non-users of loupes (compared to loupes users), claimed that they weaken the eyes, require long adjustment, and cause discomfort.

CONCLUSION

Although the use of loupes in general dentistry is becoming more prevalent, there is still a need to raise awareness for this vision aid among pediatric dentists while promoting its advantages, to reap benefits associated with their usage.

Intraoperative posture and workload assessment in vascular surgery

Quantifying the workload and postural demand on vascular surgeons provides valuable information on the physical and cognitive factors that predispose vascular surgeons to musculoskeletal pain and disorders. The aim of this study was to quantify the postural demand, workload, and discomfort experienced by vascular surgeons and to identify procedural factors that influence surgical workload. Both objective (wearable posture sensors) and subjective (surveys) assessment tools were used to evaluate intraoperative workload during 47 vascular surgery procedures. Results demonstrate unfavorable neck and low back postures as well as high pain scores for those body segments. Additionally, workload from subjective surveys increased significantly as a function of operative duration, and mental workload was high across all procedure types. Neck postural risk exposure and physical demand were among the variables that increased with surgical duration, procedure type, and loupes used by the surgeons. Correlations among postural angles and pain scores showed consistency between the objective assessment and the subjective surveys for neck and trunk. The authors believe that the results of this study highlight the need for developing mitigating measures such as ergonomic interventions for vascular surgery.

Hand replantation using loupe magnification in a resource constrained environment: Case report

Hand replantation is a common surgical procedure worldwide. However, this practice is underdeveloped in many resource-constrained countries in part due to a lack of surgical microscopes. We present a patient successfully managed using loupe magnification.

A 17-year-old patient presented with an amputated right hand secondary to a chaff cutter. After an 8-hour surgical procedure, the amputated hand was successfully re-attached to the stump using loupes. The patient's functional recovery was satisfactory after two years of follow-up.

In conclusion, replantation of extremities can be successfully achieved using loupe magnification. Loupes should be considered an alternative to operating microscopes for replantation of extremities especially in resource-constrained countries.

[Effects of loupes and microscope on the prosthodontist's posture from ergonomic aspects]

OBJECTIVE

To assess the effects of loupes and microscope on the posture of prosthodontists when preparing the laminate veneer, and to assess the clinical value of loupes and microscope from the ergonomic aspects.

METHODS

Twenty young prosthodontists from Department of Prosthodontics, Peking University School and Hospital of Stomatology were recruited into this study, which was a prospective, single blind, self-control trials. The research hypothesis was concealed and the participants were deceived about the precise purpose of the study to counterbalance the lack of direct blinding. The prosthodontists prepared laminate veneers of open window type in the artificial dental model, under routine visual field (control group), 2.5× headwear loupes (loupes group), and 8× operating microscope (microscopic group) by turning. The participants were photographed from profile view and front view. Thereafter, the subjective assessment was performed by themselves using the visual analogue score (VAS). The expert assessment was performed by two professors using modified-dental operator posture assessment instrument on the basis of photographs of the profile view and front view.

RESULTS

The subjective assessment scores for the control group, loupes group and microscopic group were 4.55±1.96, 7.90±1.12, and 9.00±0.92, respectively. There was significant difference between the three groups' subjective scores (P < 0.05). The expert assessment scores for the control group, loupes group and microscopic group were 16.38±1.52, 15.15±1.30, and 13.60±0.88, respectively. There was significant difference between the three groups' expert assessment scores (P < 0.05). Specifically, the three groups' expert assessment scores were significantly different (P < 0.05) in trunk position (front to back) (1.33±0.41, 1.03±0.11, 1.00±0.00), head and neck position (front to back) (2.75±0.38, 2.13±0.36, 1.23±0.38), elbows level (1.38±0.43, 1.40±0.45, 1.13±0.22), and shoulders level (1.43±0.41, 1.23±0.34, 1.13±0.28). Thereinto, the microscopic group was better than loupes group in head and neck position (front to back) and elbows level (P < 0.05).

CONCLUSION

Loupes and microscope improve the posture of the prosthodontist when preparing the laminate veneer, in which the microscope is better than loupes. Therefore, the magnification devices have clinical value from the ergonomic aspects.

Microvascular anastomosis using loupes and smartphone magnification: Experimental study for application to limited-resource environments

Finger revascularization has been performed without a microscope in limited-resource environments only when absolutely necessary. This experimental study sought to assess the feasibility of microvascular anastomosis in rats performed using loupes or smartphone magnification. Thirty rats were divided into three groups of 10 individuals according to the magnification method used: operating microscope (control group M), surgical loupes (group L) and smartphone (group S). The infrarenal aorta was dissected under a microscope, then anastomosed by interrupted sutures using the group-specific magnifying device. The main analytical criteria were vessel diameter, anastomosis duration, immediate flow patency (T0), patency after one hour (T1) and anastomosis quality. Anastomosis duration was comparable between groups M and L, but was twice as long in group S. The number of leaks at clamp removal was higher in group S. Patency rates at T0 and T1 were 100% in groups M and L, but were significantly lower in group S. The anastomosis quality was low in group L and poor in group S. Anastomosis of digital arteries using loupes is possible, but the resulting quality is lower than with a microscope. Current smartphones are not adequate for performslt ing microvascular repairs in a living model.

Line production system for multiple lymphaticovenular anastomoses

BACKGROUND

A drawback of multiple lymphaticovenular anastomoses (LVAs) is the need for at least two microsurgeons and the same number of microscopes. In practice, many hospitals find it difficult to access such resources. We have developed a novel line production system (LPS) to address this problem. We assessed whether or not the LPS is better than the conventional dual microscope (DM) system when performing multiple LVAs.

METHODS

An LPS group, wherein a novice microsurgeon used loupes to dissect lymphatics and an expert microsurgeon used a microscope to perform the LVAs, and a DM (control) group, wherein the surgeons used microscopes to perform the LVAs. We recorded the lymphatic detection rate through the loupes and the diameter of the detected lymphatics. We also investigated the impact of using the LPS by comparing the number and quality of LVAs and improvement in lymphedema between the study groups.

RESULTS

The mean lymphatic detection rate was 81%±15.60%, and the mean size of lymphatics was 0.44 ± 0.12 mm in the LPS. The number of LVAs/h in LPS was significantly higher than that in DM (2.15 ± 0.20 vs. 1.38 ± 0.17; p < 0.01). The number of successful LVAs/h in LPS was significantly higher than that in the DM (2.08 ± 0.22 vs. 0.84 ± 0.14; P < 0.01). Mean rate of improvement in LEL index was significantly higher than that in DM (9.36 ± 1.85 vs. 6.93 ± 1.73; P < 0.01).

DISCUSSION

The number and quality of the LVAs increase using the LPS, which leads to further improvement in lymphedema, with fewer microscopes and microsurgeons and a shorter operating time.

Visual Perception and Acuity of Hand Surgeons Using Loupes

PURPOSE

To assess the visual performance of Swiss hand surgeons in an environment similar to their workplace. The influence of Galilean (lenses only) and Keplerian loupes (lenses and prisms), the surgeon's age, and the credibility of a self-assessment of his or her own optical performance were evaluated.

METHODS

Sixty-three hand surgeons between 29 and 68 years of age with 70 loupes were included in the study (Galilean n = 35, Keplerian n = 35). The visual performance as surgeons was self-assessed on a modified visual analog scale and objectively measured with miniaturized visual tests in a simulated clinical setting. We evaluated the influence of the optical device by comparing Galilean and Keplerian loupes and the influence of the surgeon's age by comparing 2 subgroups: < 40 years and ≥ 40 years.

RESULTS

The correlation between self-assessment and objective visual performance was weak, with a Spearman rank correlation coefficient of 0.25. The near visual acuity with habitual optical aids showed considerable variability, with a range of 300% in the dimension of the smallest detected structure. The near visual acuity was significantly lower in the older group ≥ 40 years than in the younger group < 40 years with both Galilean and Keplerian loupes. Keplerian loupes allowed a significantly higher visual performance than Galilean loupes. Surgeons 40 years or older using Keplerian loupes had a similar visual acuity to surgeons younger than 40 years with Galilean loupes.

CONCLUSIONS

The magnified near vision of hand surgeons showed an important individual variability. Self-assessment was not a valuable instrument for surgeons to estimate their own near vision. Hand surgeons older than 40 years should use higher magnification loupes.

TYPE OF STUDY/LEVEL OF EVIDENCE

Diagnostic III.