Endoscopic approach for carotid artery surgery

Carotid Endarterectomy Surgical Simulation Model Using a Bovine Placenta Vessel

BACKGROUND:

Carotid endarterectomy (CEA) is a common, well-developed surgical procedure. Although surgical simulation is gaining in importance for residency training, CEA practice opportunities for surgical residents are limited.

OBJECTIVE:

To describe a new haptic CEA model.

METHODS:

Six bovine placentas were used to create the model. Each placenta provided about 6 large arterial and venous bifurcations. In total, 36 large-vessel bifurcations were dissected and prepared for the CEA simulation. Bovine placenta vessels were arranged to simulate the common carotid artery (CCA), internal carotid artery (ICA), and external carotid artery (ECA). The diameters and wall thicknesses were measured and compared with human CCA, ICA, and ECA parameters.

RESULTS:

All bovine placentas provided vessels suitable for modeling carotid artery bifurcations and CEA training. Mean ± SD diameters of simulated CCAs, ECAs, and ICAs were 11.2 ± 1.8, 4.3 ± 0.5, and 9.8 ± 3.0 mm, respectively, from nondilated veins and 8.7 ± 1.4, 4.4 ± 1.3, and 7.2 ± 1.7 mm, respectively, from nondilated arteries. Mean vessel wall thicknesses were 2.0 ± 0.6 mm for arteries and 1.4 ± 0.5 mm for veins. Placental vessel tissue had dimensions and handling characteristics similar to those of human carotid arteries. The CEA procedure and its subtasks, including vessel-tissue preparation and surgical skills performance, could be reproduced with high fidelity.

CONCLUSION:

A bovine placenta training model for CEA is inexpensive and readily available and closely resembles human carotid arteries. The model can provide a convenient and valuable simulation and practice addition for vascular surgery training.

Extracervical approaches to endoscopic thyroid surgery

There is increasing demand for surgical procedures which avoid visible scars while maintaining optimal functional and ideal cosmetic results, without compromising the safety or effectiveness of the procedure. Endoscopic techniques have been adapted to abdominal and pelvic surgery and increasingly employed over the past three decades. Although hampered by the absence of a natural cavity, endoscopic techniques have been adapted to surgery in the neck for the past 15 years, particularly for the thyroid gland. While earlier attempts at endoscopic thyroid surgery were performed through incisions in or near the midline of the neck, recent techniques have been developed to place the incisions and endoscopic ports extracervically, or at least away from the midline region of the neck, rendering the cosmetic result more acceptable. Most of these approaches are through the axilla, breast, chest wall or a combination of approaches. Visualization of the thyroid and rate of complications with these approaches are equal to those attained with older endoscopic approaches. Careful patient selection is important for endoscopic surgery. Complications unique to the endoscopic approach are mostly related to insufflation of cervical tissues with pressurized CO(2).

Transoral endoscopic neck surgery: feasibility and safety in a porcine model based on the example of thymectomy

BACKGROUND

In anatomical studies and cadaver dissections, we developed an endoscopic transoral access to the anterior neck region to reduce surgical access trauma. Through a sublingual trocar and two additional trocars in the vestibule of the oral cavity, the pretracheal and thyroid region was reached with standard laparoscopic instruments.

METHODS

We conducted an experimental trial in five pigs under general anesthesia to estimate the safety and feasibility of the method; via this approach, the thymus was partially resected. Perioperative antibiotics were administered but analgesics were not given in the postoperative course. Oral intake and behavior were observed during the following 2 days. After necropsy, examination of the access route took place by means of dissections. The tissue surrounding the working trocar was histologically examined.

RESULTS

The pretracheal region could be reached without a problem and the procedure was performed almost "bloodlessly" in an anatomically defined layer. The intervention time decreased successively. Postoperative awakening was uneventful. Regular oral food intake was observed after 2-3 h. Pain reactions were not registered during the entire postoperative phase. After dissection, all relations appeared inconspicuous (no infections, fresh/old hematoma). Two local encapsulated seromas were observed. Histologically, only a mild tissue reaction was noted.

CONCLUSION

In this study, the endoscopic transoral approach to minimally invasive neck surgery seemed safe and feasible. Minimally invasive endoscopic procedures in the anterior neck region could be a possible application of this new approach.

Macro Anatomical Investigations of the Cranial Cervical Ganglion in Domestic Pig (Sus scrofa domesticus)

In this study, the left and right cranial cervical ganglia (ganglion cervicale craniale) of eight young (four male, four female) domestic pigs weighing around 70-80 kg were inspected macro anatomically. The cranial cervical ganglion (CCG) was found cranio-ventrally of the distal ganglion of the vagus nerve, medial of the jugular process extremity, ventral of the atlas, dorsal of the epiglottis base and medial of the common root (CR) established by the internal carotid and occipital arteries. The internal carotid nerve and jugular nerve ramified from the cranial part of CCG. The jugular nerve gave branches that merged with the vagus and glossopharyngeal nerves. Other nerve branches originating from the cranial part of the ganglion reached to the external carotid artery and CR. The internal carotid nerve varied among cadavers in number of branches (two to four). These branches did not travel along the side of the internal carotid artery. The central part of CCG gave thin nerve branches that reached to various anatomical structures including the first and second cervical nerves, wall of the pharynx, accessory nerve, hypoglossal nerve, vagus nerve, external carotid artery and CR. The caudal part of CCG gave nerve branches that merged with the vagus, cranial laryngeal nerves, and common carotid artery. The external carotid nerves, which were two or three in number, also originated from the caudal part of CCG. In conclusion, the nerves ramifying from CCG of the pig varied in number among cadavers. Compared with literature raised in other species, there are also differences in number of nerve branches and course pattern of these nerves.

Endoscopic sentinel lymphadenectomy as a new diagnostic approach in the N0 neck

Sentinel lymphadenectomy was developed to reduce the extent of surgical interventions in cancer patients. The sentinel node (SN) concept was first established for melanoma and breast cancer; within some years, it also became increasingly popular for head and neck cancer. As soon as the required sensitivity of the method proves to be feasible in the daily clinical routine, the discussion about the best surgical approach to single or multiple SN(s) will arise. Different objectives may here compete with each other. The incision should render the best exposure of the operation site and should be expandable in case further lymph node regions have to be dissected. Finally, a good functional as well as a good cosmetic result is desirable. Endoscopic lymph node excisions were performed in patients suffering from squamous cell carcinoma of the upper aerodigestive tract located in different sites (1x uvula, 2x epiglottis, 1x glottis). In preoperatively performed ultrasonic imaging (B-mode-ultrasonography), N0 necks were assessed. In contrast to previously reported endoscopic techniques in humans, the presented method requires no insufflation of carbon dioxide or external retraction of the skin. Following laser surgical resection of the primary tumor, the SN and further lymph node(s) with accumulation of tracer substance were identified and resected endoscopically via an incision that was afterwards extended to a normal neck dissection incision. Reports of histopathologic examination of the sentinel node(s) were compared to the respective neck dissection specimens. The presented method may help to reduce the degree of invasiveness frequently attributed to sentinel lymphadenectomy once the method has been established for head and neck cancer.

The ZEUS robotic system: experimental and clinical applications

Laparoscopic procedures provide shorter hospitalization, less pain, better cosmetic results, and faster returns to normal than traditional surgery. Surgeons performing them, however, are hampered by lack of tridimensional view and haptic sense, and by remoteness; but this physical gap also allows robotic and computer interfaces. The computer digitizes surgical movements and images and modifies this information to filter out nonfinalized movements such as tremor, increasing dexterity and precision. Digitized information can also be transmitted to remote locations, allowing surgical care in remote or underserved areas, and enhancing surgical education. There are several robotic surgical systems available; this article reviews the experimental and clinical use of the ZEUS robotic system and discusses its possible role in the future operating room.