No abstract

Surgery in the distal carotid sheath is challenging because access is difficult and injury to the seventh, ninth, tenth and twelfth cranial nerves may result in considerable morbidity. A number of techniques have been described to facilitate exposure of the upper reaches of the internal carotid artery or para-arterial structures, including division of the digastric muscle, resection of the styloid process, temporomandibular joint subluxation, mandibular osteotomy, partial rnastoidectomy and opening of the bony carotid canal'-4. In this report the use of a laparoscope to visualize carotid dissection at the base of the skull through a standard neck incision is described. Surgical techniqueA 56-year-old woman with a history of hypertension and persistent tachycardia was found to have a markedly raised concentration of urinary free catecholamines in association with a lump in the right side of the neck. Investigations revealed a neuroectodermal turnour within the carotid sheath, involving the vagus nerve and extending into the jugular foramen (Fig. I ) .Through a routine exposure the proximal tumour was dissected from the carotid bifurcation. A 10-rnm diameter laparoscope and camera (Dyonics; Smith and Nephew, Cambridge, UK) attached to a light source and video monitor Fig. 1 Sagittal magnetic resonance image showing a large rightsided mass in the neck with a dumbell-shaped extension into the bony jugular foramen on the base of the skull Paper accepted 15 October 1996 1010 Fig. 2 View of the proximal extent of the tumour, internal carotid artery and glossopharyngeal nerve as seen through the laparoscope during dissection was then inserted into the open wound to visualize the distal internal carotid artery, the ninth and twelfth nerves, the tumour mass entering the base of the skull and the tips of the dissecting instruments working beyond the upper margin of the wound (Fig. 2), allowing safe completion of the excision. Histological and biochemical assessment demonstrated complete resection of the phaeochromocytoma and the patient made a good recovery. Initial difficulties with swallowing resolved spontaneously. DiscussionAdequate visualization of the contents of the carotid sheath is essential during surgery on the distal internal carotid artery and associated structures. The use of a laparoscope to guide distal dissection allowed successful resection of a malignant tumour extending into the jugular foramen through a standard incision. The method provides clear, magnified images of the operation site and requires little expertise in addition to that required for conventional surgery on the distal carotid artery, other than the ability to operate while observing the procedure on a nearby monitor.Video assistance may be valuable during difficult carotid surgery, such as high aneurysm repair, to allow precise dissection of the artery distal to the lesion, preservation of the cranial nerves (particularly the glossopharyngeal) and clamp placement near the skull base. ReferencesSandrnann W, Hennerici M, Aulich A, Kniemeyer...