Use of the Smith’s Spreader as a Self-Retaining Retractor in the Direct Approach to Clival Tumours – A Technical Note

Abstract

The traditional Le Fort level 1 osteotomy has proven to be an effective in approaching central skull base lesions. The challenge being - stabilization of the down-fractured maxilla in an amenable position for tumour resection. The authors describe a simple technique to overcome the task of stabilizing the down-fractured maxilla.

Introduction

Cranial base surgery is challenging and technique sensitive owing to its anatomy and the structures surrounding it that are vital for normal function. Due to limited access and exposure, resection of extensive central skull base lesions and obtaining disease-free margins without causing significant morbidity is often a difficult task [1]. Access to the clival-skull base region can be gained through multiple approaches, viz., transcranial, transfacial, transbasal, transnasal. Although in recent years skull base surgery has seen remarkable advances, such as minimally invasive approaches using endoscopic technologies, central skull base lesions still pose a technical challenge [2].

The transmaxillary approach, provided through Le Fort 1 level osteotomy, dates back to 1859 when von Langenbeck described the horizontal maxillary osteotomy. The technique was then used by Cheever in 1867 for removal of a tumour from the nasopharyngeal region [3]. Rene LeFort, later in 1901, described the classic lines of midface fractures, eventually giving these controlled surgical procedures their nomenclature [4]. The Le Fort 1 level access osteotomy and its variations have proven to afford wide exposure to the clival-skull base region, and towards the end of the twentieth century were considered the procedure of choice for access to tumours of the skull base. This approach provides an appropriate angle of view for large clival lesions extending superiorly beyond the sella turcica [5]. However, stabilization of the down-fractured maxilla while performing tumour resection remains a challenge. In this technical note, we describe a simple method to stabilize the down-fractured maxilla during access surgery to the skull base.

Technique

A 22-year-old female presented with a recurrent aneurysmal bone cyst involving the clival-sphenoid sinus region. Previously she underwent tumour resection via transnasal approach with endoscope assistance. A recent contrast-enhanced computed tomography revealed a lesion involving the clivus that extended into the nasal cavity and nasopharynx, and this time a Le Fort 1 level access osteotomy was planned to gain direct access to the tumour. A transfacial Le Fort 1 level access osteotomy was performed, the maxilla was then down-fractured, and tumour resection was carried out under microscope assistance and navigation guidance. In traditional Le Fort 1 osteotomy procedures, the Smith Spreader is used to complete the osteotomy and facilitate down-fracture of the maxilla. In our case, we further utilized this instrument as a self-retaining retractor by placing the beaks of the instrument between the osteotomized bone structures, thereby helping to focus the microscope and achieve proper instrumentation in the surgical field. As the Smith Spreader is a non-ratcheted instrument, a cut glove ring was applied to compress it to the desired extent and hence stabilize it in the given position (Fig. 1).

Fig. 1.

Left side: Down-fractured maxilla maintained in position with the help of a Smith’s spreader. Right side: Smith spreader stabilized with cut glove ring

Discussion

Traditional Le Fort level 1 osteotomies, as stated earlier, have proven to provide wide exposure to the clival-skull base region. Self-retaining retractors are generally used for the purpose of stabilizing the maxilla. These however would be cumbersome, especially during microscope-assisted procedures. Other methods such as use of Rowe forceps, Tessier blunt zygomatic hook, J stripper, Volkmann 1-pronged retractor to pull down the Le Fort 1 segment during instrumentation have been documented in literature. Some surgeons manually hold the Le Fort 1 segment with their fingers – however, manual retraction runs the risk of obliterating the view of the cavity. Hook-like instruments apply undue pressure on the lower lip and are difficult to stabilize by the assistant [6]. A Smith Spreader, on the other hand, is comparatively less bulky, atraumatic to surrounding tissues during use, and is a part of the maxillofacial surgeon’s armamentarium. One can also quickly increase or decrease the extent of exposure with ease and as per operator convenience.

In conclusion, the described technique can be performed with ease, requires no extra surgical instruments, thereby providing the surgeon with a simple solution to overcome the challenge of stabilizing the down-fractured maxilla.

Declarations

The authors would like to declare that there are no potential conflicts of interest, and received no funding to assist preparation of this manuscript. Informed consent was taken from the patient and patient attendants prior to the procedure.