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The field of skull base surgery has expanded dramatically the surgical horizons in the treatment of skull base neoplasms, which, previously, were considered inoperable because of their locations and relation to vital structures. This article aims to offer improved understanding of surgical indications and appreciation for some of the details of surgical techniques involved.

EDITOR'S NOTE: The best surgical approaches for the treatment of chronic inflammatory frontal sinus disease have been hot ly d e b a t e d ove r the las t 100 years. The pendulum has been swinging back and forth between i n t r anasa l and e x t e r n a l approaches. This "Di f f icul t Decisions" article is dedicated to this topic. Four cases have been presented to two authorities in this field, Dr. Jonas Johnson and Dr. Steven Schaefer. The following issues are discussed: radiologic findings; pathophysiology; medical and surgical treatment; advantages and disadvantages of techniques; complications; and followup. Representative CT images are presented; however, not all the images provided to the authors are i nc l uded . We hope the reader will f ind the discussion stimulating and educational. Note: The following abbreviations are used in the illustrations accompanying the CT scans: FS, frontal sinus; C, crista galli; MT, middle turbinate; NS, nasal sinus; MS, maxillary sinus; LP, lamina papyracea; IT, inferior turbinate.

In this article, case studies from four separate clinicians are presented along with comments. These cases offer unusual examples of problems that occur with endoscopic sinus surgery.

An update regarding the selective application of CT scanning in acute laryngeal trauma is presented for a period encompassing 9 years. A study group of 16 patients from a larger population of 52 patients was identified as having undergone CT scanning as part of their clinical management. A rationale is presented for the use of scanning in certain injuries, and the outcome of medical and surgical treatment is discussed.

Cortical function was evaluated in 26 subjects with spasmodic dysphonia. Quantitative topographic electrophysiologic mapping (QTE) was employed to provide quantitative analyses of EEG spectra and auditory and visual long-latency evoked potentials. Single-photon emission computed tomography (SPECT) of the cerebral transit of Xenon-133 was used to evaluate regional cerebral blood flow. Left hemispheric abnormalities in cortical function were found by both techniques in 10 subjects and by at least one technique in 18 subjects. Right hemispheric abnormalities were observed by both techniques in 8 subjects and by at least one technique in 18 subjects. Most patients with cortical dysfunction in one hemisphere had cortical dysfunction in the other, while only 4 subjects had unilateral lesions as found by one of the two techniques. Eight subjects were normal by all measurements. Underlying structural abnormalities were detected by magnetic resonance imaging in 5/24 subjects. However, functional abnormalities (SPECT or QTE) were not observed at sites of structural abnormalities. SPECT and QTE were significantly related in identification of left hemispheric dysfunction (p = .037) with a trend in the right hemisphere (p = .070), and a significant congruence of SPECT and QTE findings occurred in the left anterior cortical quadrant (p = .011). These findings indicate that dysfunction of cortical perfusion and/or cortical electrophysiology is associated with spasmodic dysphonia in the majority of subjects studied.

The posterior approach to sphenoethmoidectomy represents an alternative to the better known modifications of endoscopic paranasal sinus surgery. We present our modifications and experience with this technique over the last 4 years, and explain our rationale for selection of patients to be managed by this approach. This operation has proven useful in patients with extensive sinus disease, and/or previous surgery that has resulted in loss of normal anatomic landmarks to the sinuses.

The acute surgical management of the severely injured larynx is among the more demanding problems in laryngology, with early treatment decisions determining the outcome of both the airway and voice. To assist the physician with such decision-making, we report the rationale and operative techniques used at our institution to surgically manage 62 of 120 patients with acute laryngeal injuries for more than two decades. Such experience hopefully will also serve to help resolve several of the prevailing controversies over the care of such patients.

For 11 years, we primarily relied on frontal sinus oblit­ eration with fat via an osteoplastic flap approach to treat the majority of patients with medically refractive, chronic frontal sinusitis. For the past 4 years, we have primarily used an endoscopic, intranasal approach for initial surgi­ cal management of patients with disease similar to those treated in the earlier ll-year period. We made this tran­ sition to endoscopic frontal sinusotomy because of the following: 1. The advent of rigid fiberoptic endoscopes provides excellent visualization of the frontal recess and medial frontal sinus. 2. Recognition of the role of the anterior ethmoids in recurrent frontal sinusitis and the ability afforded to op­ erate at this site by endoscopes. 3. Knowledge of such surgery being used in Europe. 4. Our desire to minimize the surgical technique for the initial treatment of medically refractive disease.l" Last year, we reported our initial experience with en­ doscopic frontal sinusotomy. This article updates that experience and better describes our surgical technique. 1

BACKGROUND Lateral approaches have traditionally been used to gain access to lesions of the infratemporal fossa (ITF). However, dysfunction of the facial nerve secondary to its translocation, conductive hearing loss, and dental malocclusion because of mandibular head resection or dislocation are significant limitations associated with some of these approaches. Although facial nerve translocation and extended maxillotomy approaches avoid some of these drawbacks, they are invasive and require extensive osteotomies and facial incisions. To avoid these potential complications and maintain an extranasal/extraoral exposure, we studied the use of a lateral and posterior extension of an anterior transmaxillary approach to the cavernous sinus. METHODS The study was performed on 12 cadaver specimens and two dry skulls. An initial nasolabial fold incision, followed by an en bloc osteotomy of the anterior and lateral maxilla provides a window into the medial ITF. After osteotomy of the pterygoid plate and the posterior maxillary wall, the floor of the middle fossa is exposed to reveal the mandibular and maxillary divisions of the trigeminal nerve exiting their respective foramina. The floor of the middle fossa is then drilled postero-medial to the foramen ovale to gain access to the course of the C3-C4 portion of the petrous carotid artery and the eustachian tube. The upper two-thirds of the clivus and the pituitary gland are accessed after drilling of the floor of the sella turcica and form the posterior limit of this exposure. RESULTS The technique offers a trajectory to the medial ITF and skull base that does not necessitate palatal splitting or opening of the nasopharynx. The anterior route avoids temporomandibular joint disruption, and spares the lacrimal apparatus and all branches of the facial nerve. In addition, the reflected pterygoid muscle can be used as a vascularized flap for closure of the skull base defect. CONCLUSION The approach may be an alternative less invasive approach to the ITF and may be suitable for ITF lesions that have minimal lateral or intracranial extension.

Temporal bones were acquired four hours post mortem from a 67-year-old cancer patient. During dissection of the left vestibular labyrinth, a glistening white, spherical concretion was found in the posterlor semicircular duct near the ampulla. The object was subsequently studied by light and scanning electron microscopy, x-ray diffraction, and x-ray energy dispersive elemental analysis. It was composed of four concentric layers: an outer zone of tabular vaterite crystals, a colorless intermediate zone of spherulitic octacalcium phosphate (OCP), and a cloudy core with inner and outer zones both composed of OCP. Examination of the vestibular receptor organs revealed severe loss of hair cells on all three cristae. Very few otoconia were present in the utricle, although the gelationous layer of the otoconial membrane was intact on the macular surface. During the year preceding his death, the patient had received 800 mg of the potentially ototoxic drug cis-platinum. The concretion described in this report was, however, probably connected with age-related degeneration rather than with any effect of the drug.

Endoscopic total sphenoethmoidectomy is a procedure reserved for the patient with extensive paranasal sinus disease. Candidates for this operation should have radiographic evidence of pansinusitis and be refractory to medical and lesser surgical management. Given these criteria, total sphenoethmoidectomy with frontal sinusotomy and antrostomy offers an excellent treatment for this patient population.