A Novel Silicone Simulation Model for Microvascular Anastomosis.

Purpose: Surgical simulation of microvascular anastomosis has become increasingly popular. There are several living and silicone models available. Current silicone models fail to accurately reproduce a vessel's loose adventitial layer, which may lead to the development of improper microsurgical technique. Our purpose is to create a realistic 3-dimensional microsurgical simulator that incorporates an adventitial vessel layer for higher fidelity manipulation of vessels. Methods: A microvascular anastomosis simulator was manufactured using metal moulds and inorganic materials. Synthetic tubing was created with a metal cylinder, 1.65 mm in diameter, painted with 2 sequential layers of silicon with a shore hardness of 2A. Silicone was allowed to fully cure in-between layers. Vessel adventitia was created with a 100-micron polyester mesh adhered to the silicone vessel exterior. Once dry, the synthetic tube is removed from the metal cylinder is then clipped to reveal the inner lumen. Both Resident and attending physicians evaluated the model with and without the adventitial layer and completed a questionnaire. Results: Grasping and manipulation of the vessel were scored on Average score 4.5 and 3 out of 5, with adventitia and without, respectively (P = .00906). Usefulness as a teaching tool was scored on average 4.9 and 4.2, with adventitia and without, respectively (P = .0232). The analysis included: simulation realism, educational utility, and overall satisfaction. Responses in all domains were favourable, suggesting the utility of this model. Conclusion: We created a realistic, high fidelity microvascular anastomosis simulator that is low cost and easily reproducible. Initial feedback is encouraging regarding realism, educational utility, and overall usefulness. Further validation is required to assess its effectiveness in resident education and skill transfer to the operating room.

Objectif: La simulation chirurgicale de l'anastomose microvasculaire gagne en popularité. Il existe plusieurs modèles de simulation vivants ou en silicone. Les modèles actuels en silicone ne réussissent pas à reproduire la couche adventitielle lâche, ce qui peut entraîner une technique microchirurgicale inappropriée. Les chercheurs voulaient créer un simulateur microchirurgical tridimensionnel réaliste doté d'une couche adventitielle pour manipuler les vaisseaux avec plus de fiabilité. Méthodologie: Les chercheurs ont fabriqué un simulateur d'anastomose microvasculaire au moyen de moules métalliques et de matières inorganiques. Ils ont créé des tubulures synthétiques à l'aide d'un cylindre métallique d'un diamètre de 1,65 mm, qu'ils ont peint de deux couches séquentielles de silicone d'une dureté Shore A de 2. Ils ont laissé le silicone durcir complètement entre les couches et ont créé la couche adventitielle à l'aide d'une maille de polyester de 100 microns fixée à l'extérieur du vaisseau de silicone. Une fois sèche, la tubulure synthétique est retirée du cylindre métallique, puis coupée pour révéler la lumière interne. Des résidents et des médecins traitants ont évalué le modèle avec et sans la couche adventitielle et rempli un questionnaire. Résultats: La saisie et la manipulation du vaisseau ont obtenu un score moyen de 4,5 et de 3 sur 5, avec et sans la couche adventitielle, respectivement (p = 0,00906). L'utilité de ce vaisseau comme outil d'enseignement a obtenu un score moyen de 4,9 et de 4,2, avec et sans la couche adventitielle, respectivement (p = 0,0232). L'analyse incluait le réalisme de la simulation, l'utilité pour l'enseignement et la satisfaction globale. Les réponses étaient favorables dans tous les domaines, ce qui laisse croire à l'utilité du modèle. Conclusion: Les chercheurs ont créé un simulateur d'anastomose microvasculaire haute-fidélité réaliste, à la fois peu coûteux et facile à reproduire. Les premiers commentaires sont encourageants pour ce qui est du réalisme, de l'utilité pour l'enseignement et de l'utilité globale. Son efficacité lors de l'enseignement aux résidents et du transfert du savoir en salle d'opération devra être validée davantage.

Surgeon-administered Ultrasound-guided Peripheral Nerve Blocks in Outpatient Procedures of the Upper Extremity.

Outpatient hand surgery is often performed in the operating room, which can result in prolonged waiting times for patients when operating room resources are limited. Few studies have explored the application of ultrasound-guided nerve blocks in the setting of outpatient hand surgery. Fifty patients were enrolled in this prospective study. Ultrasound-guided peripheral nerve blocks were performed at the level of the elbow and proximal forearm for outpatient hand surgeries. A timer was used to record the time to administer the block and time to affect. A post-procedure survey was administered, which included a numerical analogue scale (0-10) and Likert rating scale questions to characterize the patients' pain experience for receiving the block and pain during the procedure: pain experienced by patients receiving the ultrasound-guided nerve block(s) (0-10), mean: 1.84; pain experienced by patients during a procedure (0-10), mean: 0.56; surgeon satisfaction during the procedure (0-10), mean 9.78. Average time to perform the ultrasound-guided nerve block(s) was 4 minutes 58 seconds; average time from completion of the block to effect reported by patients, 5 minutes 42 seconds; the average time for performing the procedure, 21 minutes 30 seconds. Our study shows that the use of ultrasound to block peripheral nerves of the forearm is effective; <10% of patients required additional local anesthetic. The technique is safe; no complications were reported. The technique is efficient in an outpatient hand surgery setting.

Gouty Stenosing Tenosynovitis: Trigger Finger as a First Presentation of Tophaceous Gout.

Gout can lead to the deposition of tophi and chronic arthritis, for which surgical management is indicated when tophi interfere with the function of the finger. This case report discusses the management of a 37-year-old man with a past medical history of gout who presented with triggering of his small finger from gouty infiltration of his flexor digitorum profundus (FDP) tendon. An exploratory procedure that included tenolysis and release of the A1 pulley was performed. Gouty infiltration of the FDP tendon was noted intraoperatively and biopsied, which was later confirmed by histopathological analysis as being gouty tophus. The patient regained full function of the affected finger postoperatively and has since had no recurrence. Gouty tenosynovitis is a rare cause of trigger finger and should be considered as part of the differential diagnosis. Treatment for gouty tenosynovitis consists of A1 pulley release and careful excision of gouty tophus to restore tendon glide and hand function.

Validation of a novel strabismus surgery 3D-printed silicone eye model for simulation training.

PURPOSE: To demonstrate the validity of a new 3D-printed silicone model for practicing strabismus surgery, compared with the rabbit head, in terms of simulator fidelity. METHODS: In this multicenter study, a validated questionnaire was developed to assess fidelity of the model and rabbit head. Participants were asked to rate overall globe, conjunctiva, muscle, and scleral fidelity using a 5-point scale. The survey instrument was disseminated at three strabismus instruction courses: at two meetings, participants practiced on the model and rabbit head prior to completing the questionnaire; at the third, instructors demonstrated advanced surgical skills using only the model and then completed the questionnaire. Repeated measures analysis of variance compared ratings. Pearson's or Spearman's correlation evaluated correlation between years of experience to participants' responses. Qualitative data were coded into themes. RESULTS: A total of 47 participants completed the questionnaire. The model rated 18% higher than rabbit head for anatomical accuracy (mean difference, 0.667; P = 0.001) and 25% higher for position of eyes within the head (mean difference, 0.867; P = 0.006). More experienced participants were more likely to strongly agree that the silicone conjunctiva effectively mimics real conjunctiva (ρ = 0.337; P = 0.036) and that scleral tissue effectively mimics real sclera (ρ = 0.298, P = 0.042). Qualitative data supported the model. CONCLUSIONS: This study demonstrated the validity of the surgical model in terms of fidelity compared to the rabbit head.

Vascularized Pedicled Proximal Phalanx Flap for Spare Part for Reconstruction of Metacarpal Avulsion Injury.

Traumatic injuries to the hand with significant loss of bone or soft tissue can be quite difficult to reconstruct and often require an innovative and flexible surgical plan for reconstruction. We present a case of a young manual laborer with a significant crush avulsion injury involving his third and fourth metacarpals. We were able to preserve his fourth metacarpophalangeal joint by utilizing a pedicled vascularized proximal phalanx flap from the nonsalvageable third digit to reconstruct and provide osseous stability to the fourth metacarpal. The patient had excellent functional and aesthetic outcomes with full return to work at his farm by less than 12 months postoperatively.

The Canadian Model for Instituting Wide-Awake Hand Surgery in Our Hospitals.

Clinic-based hand surgery performed under local anesthetic has been steadily increasingly performed in Canada for 50 years. The drive for its development stems from the Canadian health care system's finite funding structure and resources. Benefits have extended far beyond cost and garbage reduction. It has resulted in greatly improving patient care by increasing comfort and safety with the elimination of sedation, the tourniquet, night surgery, and by improving access to care. This article details the rationale and development of clinic-based hand surgery from a Canadian perspective and provides tips and strategies for other centers looking to implement a similar clinic.

Three-dimensional Printed Surgical Simulator for Kirschner Wire Placement in Hand Fractures.

Closed reduction and percutaneous pinning (CRPP) of hand fractures can be a deceptively challenging procedure that requires significant hands-on time to teach and learn. We created a realistic three-dimensional simulator that can be used for teaching junior residents the CRPP. Computer-aided design and computer-aided manufacturing (CAD/CAM) software was used to create a three-dimensional hand model incorporating several common hand fractures: Bennett's fracture, transverse fifth metacarpal neck, and transverse second proximal phalanx. Three-dimensional printing was used to create molds in which the bones and soft tissue were poured. A polyurethane foam was utilized for the bones with iron incorporated to render them radiopaque, whereas silicone of varying viscosities was used for the soft tissues. Five plastic surgery residents and 5 consultants evaluated the model. Individuals then completed an anonymous 12-question survey evaluating the model based on realism, educational utility, and overall usefulness. Survey responses obtained from both residents and consultants were strongly in favor of the simulator. Average realism was graded as 4.48/5 by residents and 4.68/5 by consultants. Average educational utility was graded as 5/5 by residents and 4.95/5 by consultants. Average overall usefulness was graded as 5/5 by both groups. We created an anatomically accurate and realistic simulator for CRPP of hand fractures that was low cost and easily reproducible. Initial feedback was encouraging in regard to realism, educational utility, and overall usefulness.

Accuracy of medical models made by consumer-grade fused deposition modelling printers.

BACKGROUND: Additive manufacturing using fused deposition modelling (FDM) has become widely available with the development of consumer-grade three-dimensional printers. To be useful in maxillofacial surgery, models created by these printers must accurately reproduce the craniofacial skeleton. OBJECTIVE: To determine the accuracy of consumer-grade FDM printers in the production of medical models compared with industrial selective laser sintering (SLS) printers. METHODS: Computed tomography images of a dry skull were manipulated using OsiriX (OsiriX, Switzerland) and ZBrush (Pixologic, USA) software. Models were fabricated using a consumer-grade FDM printer at 100 µm, 250 µm and 500 µm layer heights and an industrial SLS printer. Seven linear measurements were made on the models and compared with the corresponding dry skull measurements using an electronic caliper. RESULTS: A dimensional error of 0.30% was observed for the SLS models and 0.44%, 0.52% and 1.1% for the 100 µm, 250 µm and 500 µm FDM models, respectively. CONCLUSION: Consumer-grade FDM printers can produce medical models with sufficient dimensional accuracy for use in maxillofacial surgery. With this technology, surgeons can independently produce low-cost maxillofacial models in an office setting.

HISTORIQUE: La fabrication additive faisant appel à la modélisation par dépôt de fil en fusion (FDM) s'est généralisée grâce au développement des imprimantes tridimensionnelles pour consommation courante. Pour être utiles en chirurgie maxillo-faciale, les modèles créés par ces imprimantes doivent reproduire le squelette craniofacial avec précision. OBJECTIF: Déterminer la précision d'imprimantes FDM pour consommation courante dans la production de modèles médicaux par rapport à des imprimantes industrielles faisant appel au frittage sélectif par laser (SLS). MÉTHODOLOGIE: Les chercheurs ont manipulé les images tomodensitométriques d'un crâne séché à l'aide des logiciels OsiriX (OsiriX, Suisse) et ZBrush (Pixologic, États-Unis). Ils ont fabriqué les modèles à l'aide d'une imprimante FDM pour consommation courante, à des épaisseurs de couche de 100 µm, 250 µm et 500 µm, ainsi qu'à l'aide d'une imprimante SLS industrielle. Au moyen d'un pied à coulisse électronique, ils ont effectué sept mesures linéaires sur les modèles, qu'ils ont comparées aux mesures du crâne séché. RÉSULTATS: Les chercheurs ont observé une erreur dimensionnelle de 0,30 % dans les modèles SLS et de 0,44 %, 0,52 % et 1,1 % dans les modèles FDM à 100 µm, 250 µm et 500 µm, respectivement. CONCLUSION: Les imprimantes FDM pour consommation courante produisent des modèles médicaux de précision dimensionnelle suffisante pour être utilisés en chirurgie maxillo-faciale. Grâce à cette technologie, les chirurgiens peuvent produire eux-mêmes des modèles maxillo-faciaux à faible coût en cabinet.

Abdominal compartment syndrome following abdominoplasty: A case report and review.

Abdominoplasty is among the most commonly performed aesthetic procedures in plastic surgery. Despite high complication rate, abdominal contouring procedures are expected to rise in popularity with the advent of bariatric surgery. Patients with a history of gastric bypass surgery have an elevated incidence of small bowel obstruction from internal herniation, which is associated with non-specific upper abdominal pain, nausea, and a decrease in appetite. Internal hernias, when subjected to elevated intra-abdominal pressures, have a high-risk of developing ischemic bowel. We present a case report of patient with previous laparoscopic Roux-en-y gastric bypass who developed acute ischemic bowel leading to abdominal compartment syndrome following abdominoplasty. To the best of our knowledge, this is the first reported case in the literature. We herein emphasise on the subtle symptoms and signs that warrant further investigations in prospective patients for an abdominal contouring procedure with a prior history of gastric bypass surgery.