Head and neck surgical procedures are likely to be rapidly influenced by new developments created by the intersection of innovative practitioners and improving technology.
In a panel discussion at the Triological Society‘s 111th annual meeting during the Combined Otolaryngology Spring Meeting, researchers explained how some of those technologies are already affecting how patients are being treated today and the likelihood that those treatments will be expanded in the near future.
However, David J. Terris, MD, Porubsky Professor and Chairman of the Department of Otolaryngology at the Medical College of Georgia in Augusta, moderator of the panel, said that the use of these new technologies comes with a major caveat.
We have to hold ourselves accountable to demonstrate an advantage with these technologies, he said. These technologies must allow us to do our procedures better or safer or faster or less expensive-or preferably some combination of these.
The panel reviewed advances and techniques in:
- Endoscopic skull base surgery.
- Sentinel node biopsy in head and neck cancer.
- Endoscopic thyroid and parathyroid surgery.
- Applying robotics to laryngeal surgery.
This article will discuss the first topic; the rest will be covered in upcoming articles in ENT Today.
Advances in Endoscopic Procedures
The discussion of endoscopic resection of head and neck tumors dominated much of the conference, and the panel also looked at how the procedures are being carried out.
We see the endoscope as just one more tool to complement traditional approaches, said Ricardo Carrau, MD, Professor of Otolaryngology-Head and Neck Surgery, Director of the Maxillofacial Trauma Service, and a member of the Minimally Invasive Endoneurosurgical Center at the University of Pittsburgh Medical Center.
The same oncologic and microsurgical principles still apply, regardless of the approach, Dr. Carrau said. Since the 1960s, we have been using a variety of transfacial and transcranial procedures to take out tumors that arise in the skull base or invade the skull base.
We have achieved oncological, functional, and cosmetic goals. The transfacial procedures include incisions, osteotomies, and ostectomies. The transcranial approach involves incisions, craniotomies, and craniectomies. Our oncologic goals are local control or palliation; our functional goals are to preserve the function of the brain, the ocular system, and the cranial nerves; the cosmetic goals are to reduce scarring and loss of bone.
Dr. Carrau said that clinicians who venture into endoscopic procedures to prevent scarring and other morbidities involved in traditional surgery should gain experience slowly in developing their surgical skills with a variety of instruments. We use a bimanual technique, with two nostrils and two surgeons and four hands, he said. I advise you to have a lot of experience with both oncological principles and endoscopic techniques-and I really mean a lot of experience, because we are dealing with cancer, and the life of the patient will be at stake.
Endoscopic Surgery for Olfactory Neuroblastoma
In a series of video clips, Dr. Carrau described one such procedure-an olfactory neuroblastoma. We first debride the tumor to give us more space and better visualization. Our next step is to identify surgical landmarks. You are going to need two major landmarks for this tumor. One is the skull base, and we obtain that by performing a wide sphenoidotomy. The other is the lamina papyracea, which is identified by creating a wide nasomaxillary window. The lamina papyracea is removed on both sides to gain vascular control of the skull base. We usually will put a clip on an artery supplying the tumor and cauterize it at the same time. Septal incisions are similar as in the open approach.
The surgery can be done as sort of an en bloc procedure, but I have to tell you we have changed that technique to one that goes in layers. We remove the tumor, the mucosa, the bone, and then the dura. We think that is a safer way of removing the tumor, and it really doesn’t make any difference for the oncology margins as long as it is completely removed. We are going to treat the tumor in the same way we would with the traditional approach.
In the operation he described, Dr. Carrau noted that the tumor invaded a larger area than expected, requiring the removal of the olfactory nerves and the dura. This is because when we opened the dura, a portion of the tumor that was not visible from the nasal side had invaded the other side of the dura. If we had stopped our procedure at the dura, we would have left tumor with perineural invasion.
The tumor has to be followed and olfactory tract removed until we obtain negative margins. We are going to have the same defect as if we used the traditional approach.
Dr. Carrau said the advantage of the endoscopic approach, aside from the obvious of not having any facial incisions or scalp incisions and avoiding craniotomy, is that you have much less brain manipulation. This is almost a ‘no touch’ technique regarding the brain that allows us to include patients that before were not surgical candidates.
That is not to say that we tackle all our tumors with an endoscopic approach. You have to understand that at least 50 percent of sinonasal track tumors at our institution are managed with open approaches. If you have tumors that invade the skin, the soft tissues of the orbit, or the frontal sinus, it doesn’t make sense to do it completely with an endoscopic approach, although endoscopic techniques can really be complementary.
Although we have two camps-the traditional camp of ‘we can do it larger’ and the endoscopic camp of ‘we can do it smaller’-we really have to be able to move from one camp to the other, according to the needs of the patient, he said.
Dr. Carrau said that the development of the nasoseptal flap has become a major innovation in endoscopic reconstruction. We preserve the upper portion of the mucosa and we can move the margin of this flap according to the oncologic needs by extending the flap into the floor of the nose and then having a margin at the top. The flap has to be raised early in the surgery and can cause a problem during the surgery, but we just store it in the nasopharynx until it is time to use it. The flap is big and supple. It can reach the anterior of the skull base and the lateral skull base.
When Dr. Carrau and researchers at the University of Pittsburgh began performing the endoscopic procedures, cerebrospinal fluid leaks occurred in about one in four patients. The use of the flap immediately decreased the leak rate to 6 percent, and now it is down to 4 percent.
Of the 39 patients treated by his team, 11 operations involved esthesioneuroblastomas. The rest of the procedures included neuroendocrine tumors, adenocarcinomas, melanomas, and various other tumor types. The follow-up ranged from six to 61 months. Currently, 36 of 39 patients have no evidence of disease; three patients died of disease, at six months, 10 months, and 18 months following surgery.
Combining his data with those from the University of Miami, we have 22 esthesionseuroblastoma patients with a mean follow-up of 31 months. We had one conversion to an open approach and two positive margins. All the patients in the series, ranging from nine to 104 months postsurgery, have no evidence of disease. Three patients experienced cerebrospinal fluid leaks, Dr. Carrau said.
Endoscopy Pros and Cons
Dr. Carrau said that another advantage of the endoscopic approach is that the surgeon has better visualization of the surgical field. With microsurgery, it doesn’t matter how big you magnify it-you will get the same structure, he argued. With the endoscope, you can look around the corners.
In performing endoscopic oral cancer procedures, Dr. Carrau noted jokingly, Our philosophy is that you take bone out until you think it is too much, and then you take some more. It isn’t enough to be able to see; you have to work in the area.
He said that the disadvantages of endoscopic surgery include the fact that there is a steep learning curve, the procedures are instrumentation- and technology-dependent, it has a two-dimensional field of view, and there are some reimbursement issues that need to be solved.
Dr. Carrau said that some people might consider the necessity of requiring two surgeons as another disadvantage. However, I see that as an advantage, not really a disadvantage, he said.
The take-home message is that these cases should be handled as a team surgery; surgeons should be trained in both open and endoscopic techniques. Incremental learning is really a key to this type of procedure, he said.
He advised clinicians interested in performing the procedure using endoscopic approaches to go to courses, do various dissections, and work slowly. Keep yourself within the capabilities of your team, he said. When you move into the lateral skull base, you have to have a lot of experience on your team to handle vascular complications so you don’t have a catastrophe on your hands. Institutional support is also key. You need adjunctive, complementary specialists around you, such as interventional radiologists, who can get you out of trouble.
Dr. Carrau disclosed that he consults for Stryker Navigation and Storz Endoscopy.
©2008 The Triological Society