Intraosseous lipoma of the left frontoethmoidal sinuses and nasal cavity.

Intraosseous lipomas are very rare slow-growing benign tumors that may appear as congenital lesions or may be acquired (metaplasia from a pre-existing lipoma). Only a handful of head and neck cases have been reported in the literature. We present the first reported case of a solitary osteolipoma involving the sinonasal tract in a 66-year-old man with sinonasal symptoms. CT showed a lesion involving the left frontal sinus, extending into the ethmoid sinus with insinuation along the left middle turbinate. It appeared to be an atypical mass with areas of high attenuation (calcification) within.

Treatment of chronic rhinosinusitis with high-dose oral terbinafine: a double blind, placebo-controlled study.

OBJECTIVES: To evaluate antifungal terbinafine in patients with chronic rhinosinusitis. STUDY DESIGN: Randomized, double-blind, placebo-controlled multicenter pilot study. METHODS: Fifty-three adults with chronic rhinosinusitis received terbinafine 625 mg/day (n = 25) or placebo (n = 28) once daily for 6 weeks. Sinus secretions were collected at screening for mycology. Computed tomography was graded for extent of opacification at baseline and at week 6 using a modification of the Lund-Mackay scoring system. Patients recorded rhinosinusitis symptoms on a visual analogue scale and completed the Rhinosinusitis Disability Index. RESULTS: Positive fungal cultures were found in 41 of 53 patients (17 terbinafine, 24 placebo). (Two subjects from the Terbinafine group and one subject from the control group had no week 6 data). The mean opacification scores pre- and posttreatment for the entire study group improved from 24.2 to 22.5 in placebo (n = 26) and from 26.3 to 24.2 in terbinafine group (n = 23). The least squares means for percent change from baseline (SE) were -6.0 (8.7) for placebo compared with -7.2 (8.1) for terbinafine; 95% confidence interval for treatment difference (-18.9, 21.1); P = .91. Results were similar when only patients with positive fungal cultures were evaluated in the efficacy analysis. Investigator therapeutic evaluations and sinus symptom scores were not significantly different between the two groups at baseline or at treatment completion. CONCLUSION: Treatment with terbinafine failed to improve the symptoms or radiographic appearance of chronic rhinosinusitis even when nasal irrigation samples were positive for fungus on culture. One consideration is that the fungi isolated were not a major pathologic factor in this cohort. It is also possible that, even at high dose, terbinafine may not have maintained therapeutic levels in the nasal secretions.

Characterization of the basal temporal language area in patients with left temporal lobe epilepsy.

We evaluated 5 consecutive patients with subdural grid electrodes (including placement over the left basal temporal region) for focal resections for control of intractable epilepsy. All 5 had language dysfunction when we performed cortical stimulation over the basal temporal region (the inferior temporal gyrus, the parahippocampal gyrus) using a systematic battery of language tests. The area in which language interference could be produced began from at least 11 to 35 mm posterior to the temporal tip and ended at least 39 to 74 mm posterior to the temporal tip. The most consistently impaired language tasks were spontaneous speech and passage reading, but there was impairment of all language functions tested in some patients. Language deficits after dominant temporal lobectomy may result from resection of this area.

Ocular pseudomyasthenia or ocular myasthenia 'plus': a warning to clinicians.

Myasthenia gravis (MG) commonly presents with weakness and fatigability of the lids and extraocular muscles, which respond to treatment with anticholinesterase medication. However, certain intracranial mass lesions may mimic these features of MG; alternatively, MG may mask the signs of a coexistent intracranial mass. We describe 8 patients originally diagnosed as having MG by knowledgeable clinicians, in whom an intracranial lesion instead of, or in addition to, MG was later identified. The lesions included parasellar tumors and aneurysms. In patients presenting with clinical features of ocular MG, it is therefore essential to establish a definite diagnosis of MG, to exclude other possible causes of "pseudomyasthenia," and to exclude other diseases that might be masked by coexisting myasthenic weakness. We recommend that patients with clinical features of MG limited to the ocular or cranial musculature be thoroughly evaluated for intracranial mass lesions, using CT or MRI if warranted.

Computed tomographic three-dimensional localization and compositional evaluation of intraocular and orbital foreign bodies.

A software program designed for the Siemens Somatom DR3 computed tomographic (CT) scanner provides improved diagnosis, localization, and etiologic description of intraocular and orbital foreign bodies. The program allows information to be analyzed in two different display formats. One format is that of multiplanar reconstruction of the eye and orbit, including an "oblique CT cube" image. This format produces an accurate "three-dimensional" display of both in vitro and in vivo intraocular and orbital foreign bodies. The second display format is that of a histogram. Using this analytic mode, nonmetallic intraocular and intraorbital foreign bodies can be differentiated from each other and from metallic foreign bodies, although individual metallic foreign bodies cannot be identified with respect to specific composition. The information provided by these two display formats substantially aids the clinician in the diagnosis and management of foreign bodies located within the orbit, particularly those located within the eye.

Fine-needle aspiration cytology of monomorphic adenomas.

The diagnostic accuracy of fine-needle aspiration of salivary gland lesions is now widely accepted. The cytologic appearance of two rare monomorphic variants of pleomorphic adenomas is described. The trabecular-tubular adenoma consisted of a trabecular arrangement of uniform small cells with scant basophilic cytoplasm and round nuclei. No mucoid spheres were present. The canalicular adenoma also had a distinctive cytologic appearance consisting of papillae and interconnected canaliculi lined by a layer of columnar epithelium. Monomorphic adenomas have unique morphologic appearances that can be recognized in fine-needle aspiration cytology. Preoperative diagnosis can greatly aid the surgeon in the planning of definitive surgical excision of salivary gland neoplasms.

Relationship of the optic nerve to the posterior paranasal sinuses: a CT anatomic study.

PURPOSE: To delineate the relationship between the optic nerves and the posterior paranasal sinuses using CT data. METHODS: Direct coronal sinus CT scans of 150 consecutive patients with chronic inflammatory sinus disease were reviewed by two radiologists. Axial oblique reconstructions along the course of the optic nerve were obtained for the first 100 patients. The direct relationship between the optic nerve and the posterior ethmoid and sphenoidal sinuses was recorded, as were identations into the sinus wall, course of the nerve through the sinus region, pneumatization of the anterior clinoid process, and bone dehiscence. RESULTS: The relationship of the optic nerve to the posterior paranasal sinus fell into one of four discrete categories, type 1 through type 4. All 300 nerves were intimately related to the sphenoidal sinus. A small minority (3%) were in contact with the posterior ethmoidal sinus. Only type 4 nerves had contact with the posterior ethmoid air cell. Type 1 nerves course adjacent to the sphenoid sinus without indentation of the wall (228 nerves, 76%). Type 2 nerves course adjacent to the sphenoidal sinus, causing indentation of the sinus wall (44 nerves, 15%). Type 3 nerves course through the sphenoid sinus (19 nerves, 6%). Type 4 nerves course immediately adjacent to the sphenoidal sinus and the posterior ethmoidal air cell (9 nerves, 3%). Bone dehiscence over the optic nerve was found in 24% of the nerves; 4% of the optic nerves in our study had an associated pneumatized anterior clinoid process and 77% of these had an associated dehiscence over the optic canal. CONCLUSIONS: In all our cases the course of the optic nerve was adjacent to the sphenoidal sinus. Only 3% were in contact with the posterior ethmoidal sinus. Anatomic configurations that predispose the optic nerve to injury include type 2 or 3 optic nerves, bone dehiscence over the nerve, and pneumatization of the anterior clinoid process. These configurations are common and should be routinely sought out so that devastating complications from sinus surgery can be avoided.

The cerebral angiographic findings in Cogan syndrome.

SUMMARY: Cogan syndrome is an uncommon disorder of unknown etiology characterized by vestibuloauditory dysfunction and nonsyphilitic interstitial keratitis. To our knowledge, the case herein is the first report to demonstrate the cerebral angiographic findings of a patient with this syndrome.

Optimal CT evaluation for functional endoscopic sinus surgery.

PURPOSE: To evaluate the optimal parameters for the CT examination of patients who are having functional endoscopic sinus surgery. METHODS: CT scanning was performed on two fresh cadaveric heads in the direct coronal plane, varying the section thickness, intersection gap, scanner gantry angle, and amperage. The nasal cavity and paranasal sinuses were examined independently in a blinded fashion by four staff neuroradiologists and a staff otolaryngologist with special attention to 10 anatomic landmarks within the ostiomeatal unit that are considered important for preoperative planning. A score of 0 (nonvisualization/incomplete visualization) or 1 (clear/complete visualization) was assigned to each of these 10 landmarks. Analysis of variance was used in which reader, subject, and side were simultaneously controlled by "blocking." Multiple comparison methods (ie, Bonferroni) were used to compare the different protocols. RESULTS: We found a significant reduction in the delineation, and therefore the perception, of the ostiomeatal unit structures when the section thickness was greater than 5mm, any intersection gap was used, and the gantry angle was greater than 10 degrees from the plane perpendicular to the hard palate. However, a reduction in the radiation exposure from 200 mA to 80 mA did not affect the display of the anatomic landmarks. CONCLUSION: We found the optimal screening CT protocol for the paranasal sinuses to be a section thickness of 3 mm, no intersection gap, and a section angle within 10 degrees from the plane perpendicular to the palate. Also, owing to inherent contrast between air, soft tissue, and bone in the paranasal sinuses, a reduction in the radiation exposure parameter to 80 mA did not affect image quality.

T2 relaxation measurements in X-linked adrenoleukodystrophy performed using dual-echo fast fluid-attenuated inversion recovery MR imaging.

SUMMARY: The purpose of this study was to determine whether dual-echo fast fluid-attenuated inversion recovery MR imaging and corresponding T2 brain maps can show different zones in the affected white matter of patients with cerebral X-linked adrenoleukodystrophy. Ten male patients with cerebral X-linked adrenoleukodystrophy underwent imaging performed using dual-echo fast fluid-attenuated inversion recovery and dual-echo conventional spin-echo MR sequences. Corresponding T2 relaxation maps of the brain were generated. On the basis of dual-echo fast fluid-attenuated inversion recovery images and T2 maps, the affected white matter could be divided into two distinct zones in four patients with cerebral X-linked adrenoleukodystrophy.

In vitro evaluation of MR hypointensity in Aspergillus colonies.

PURPOSE: To demonstrate that paramagnetic elements in fungal colonies can cause hypointensity in MR images. METHODS: Aspergillus fumigatus grown in vitro was imaged with CT and MR at the time of initial inoculation and 5 days later. CT and MR images, T2 values, scanning electron microscopy, energy-dispersive analysis, and furnace atomic absorption spectrometry were performed. RESULTS: After 5 days of growth, MR images of A fumigatus revealed curvilinear hypointensities on T2-weighted images corresponding to the fungal growth. Gradient-echo images revealed two distinct components of hypointensity with different calculated T2 values. Phase-angle-difference images revealed a phase shift characteristic of magnetic-susceptibility paramagnetic effects, which corresponded to the hypointense regions on gradient-echo images. Energy-dispersive analysis and furnace atomic absorption spectrometry confirmed the presence of paramagnetic elements. CONCLUSION: It was shown that in vitro A fumigatus concentrates metal elements contained within the nutrient broth. These focal collections of calculated T2 values are caused at least partly by magnetic susceptibility effects.

Surgical resection of intrinsic brain stem lesions: an overview.

A major limitation to the effective treatment of intrinsic mass lesions of the brain stem has been the inability to clearly define the pathological anatomy radiographically. The improved soft tissue resolution offered by magnetic resonance imaging, as compared with axial computed tomography, now makes it possible not only to accurately distinguish anatomical relationships, but also to predict the pathological nature of the lesion. Accordingly, we have been encouraged to pursue a more aggressive approach to intrinsic lesions of the brain stem that appear well circumscribed on magnetic resonance imaging scan. The object of this paper is to report the successful treatment of four intrinsic lesions of the brain stem and to present an overview of the relevant published experience.

In vivo accuracy testing and clinical experience with the ISG Viewing Wand.

OBJECTIVE: A frameless stereotactic system (the Viewing Wand; Elekta Instruments, Atlanta, GA) has been developed for use with preoperative computed tomography, magnetic resonance imaging, and positron emission tomography as an adjunct for surgical planning and intraoperative navigation. This clinical study was designed to evaluate the safety, efficacy, and accuracy of the Viewing Wand in a variety of intracranial procedures. METHODS: We used this system in 250 patients undergoing a wide range of neurosurgical procedures from July 1990 to July 1994, to assess its clinical usefulness and safety. In a subset of 45 neurosurgical patients studied between March 1993 and March 1994, a battery of objective accuracy measurements was obtained before and during surgery. RESULTS: In this series, there were no instances of adverse outcomes attributable to the use of this system. A comparison of two alternative patient-image registration techniques established that the fiducial-fit method was slightly more accurate than the surface-fit method (geometric means = 2.51 and 3.03 mm, respectively). The clinical accuracy achieved with magnetic resonance imaging was nearly equivalent to that with computed tomography. CONCLUSIONS: On the basis of this clinical series, recommendations are made regarding preoperative scanning parameters, registration techniques, and methods for reestablishing registration if needed during the course of surgery. The primary clinical benefits of the wand in this series were improved intraoperative navigation and surgical safety. For most cases, the wand was also useful in planning the location and size of the scalp incision, craniotomy, or corticotomy, as well as the extent of surgical resection.

Nonlinear elastic registration of brain images with tumor pathology using a biomechanical model.

A biomechanical model of the brain is presented, using a finite-element formulation. Emphasis is given to the modeling of the soft-tissue deformations induced by the growth of tumors and its application to the registration of anatomical atlases, with images from patients presenting such pathologies. First, an estimate of the anatomy prior to the tumor growth is obtained through a simulated biomechanical contraction of the tumor region. Then a normal-to-normal atlas registration to this estimated pre-tumor anatomy is applied. Finally, the deformation from the tumor-growth model is applied to the resultant registered atlas, producing an atlas that has been deformed to fully register to the patient images. The process of tumor growth is simulated in a nonlinear optimization framework, which is driven by anatomical features such as boundaries of brain structures. The deformation of the surrounding tissue is estimated using a nonlinear elastic model of soft tissue under the boundary conditions imposed by the skull, ventricles, and the falx and tentorium. A preliminary two-dimensional (2-D) implementation is presented in this paper, and tested on both simulated and patient data. One of the long-term goals of this work is to use anatomical brain atlases to estimate the locations of important brain structures in the brain and to use these estimates in presurgical and radiosurgical planning systems.

Failed arthrodesis of the spine for severe spondylolisthesis. Salvage by interbody arthrodesis.

Four patients who had had grade-III or grade-IV symptomatic spondylolisthesis and a failed posterior or posterolateral arthrodesis were treated with transperitoneal anterior lumbosacral interbody arthrodesis and fixation with a fibular graft; the procedure was sometimes followed by posterolateral arthrodesis of the spine. The patients were examined ten to twenty-two years after the salvage operation. At follow-up, all had a solid fusion of the fifth lumbar to the first sacral vertebra. No neurological deficits had worsened and no iatrogenic neurological deficits had developed. The slip angle had improved by an average of 23.2 degrees (range, 12 to 35 degrees).

Endoscopic middle meatal antrostomy: theory, technique, and patency.

Ostial obstruction is a major factor in the pathogenesis of sinusitis. Detailed diagnostic evaluation in patients with maxillary sinusitis demonstrates the prominence of disease in the ethmoidal infundibulum and in adjacent ethmoid cells. Surgical procedures performed to improve maxillary sinusitis by inferior meatal antrostomy leave residual disease in the ostiomeatal area and may result in persistent mucociliary obstruction. Historically, the possibility of closure following ostial manipulation and the importance of dependent drainage of the maxillary sinus have been cited as arguments against the middle meatal approach. In this study of middle meatal antrostomies the patency rate was 98% between 4 and 32 months. The postoperative endoscopic findings and symptomatic improvement suggest that mucociliary clearance occurs through the surgically widened ostium. We conclude that endoscopic middle meatal antrostomy does not lead to ostial stenosis.

Coronal CT scan abnormalities in children with chronic sinusitis.

Coronal computed tomography (CT) scans are currently the optimal study to display the normal and abnormal anatomy in children with chronic and recurrent acute sinusitis after failure of medical therapy. To assess the extent and distribution of disease as well as associated anatomic abnormalities in this pediatric population, 74 coronal CT scans of children with continued symptoms of sinusitis after failure of extensive medical therapy were reviewed retrospectively. Twelve children with cystic fibrosis showed the characteristic features of medial displacement of the lateral nasal wall in the middle meatus and uncinate process demineralization, creating the appearance of a maxillary sinus mucocele. Nine of these 12 children had increased attenuation in the maxillary sinus on soft-tissue windows. In the remaining 62 children, a significantly greater frequency of disease, when compared with that reported for adults, was seen in the maxillary, anterior ethmoid, posterior ethmoid, and frontal sinuses. Children with asthma (n = 33) had more extensive disease. Bony anatomic abnormalities were similar to those reported for adults, except for a lower incidence of septal deformity.

Physiologic mucosal changes within the nose and ethmoid sinus: imaging of the nasal cycle by MRI.

Magnetic resonance studies frequently demonstrate increased T2-weighted signal in the nasal area. To further evaluate this phenomenon, several MRI examinations of the nasal cavity were performed within an 8- to 12-hour period. The study demonstrated that changes alternated from side to side and were interrupted by the administration of topical vasoconstriction, confirming imaging of the normal nasal cycle. Changes were also observed within the ethmoid sinuses. Signal intensity on T2-weighted images during the congested phase was similar to inflammatory mucosa. Occasionally, these changes make interpretation of the extent of pathology difficult in patients with sinus disease, and raise the possibility of inflammatory pathology in asymptomatic patients. Awareness of MRI imaging of nasal cycle should reduce the likelihood of diagnostic errors and provides another method for study of this physiologic phenomenon.

Three-dimensional reconstruction of the feline larynx with serial histologic sections.

This paper reviews a new technique to develop high-resolution three-dimensional (3-D) images of the larynx using histological sections. Three-dimensional computer-reconstructed histological sections of the cat are used in this study to evaluate the recurrent laryngeal nerve (RLN) in its true anatomic course, with emphasis on its relationship to surrounding structures (laryngeal framework). A cat model was used because of specimen availability and technical ease of tissue preparation. Computer-reconstructed serial histologic sections add a new dimension to the study of laryngeal anatomy, laryngeal trauma, and growth patterns of laryngeal cancer. The technical aspects of three-dimensional reconstruction and future applications are discussed.

Endoscopic sinus surgery for mucoceles: a viable alternative.

Functional endoscopic surgery affords the potential for dramatically reducing operative morbidity of surgery for paranasal sinus mucoceles by offering a minimally invasive approach under local anesthesia. Following surgery, direct endoscopic visualization of the area enables accurate follow-up. Unlike sinus obliteration, the ability to accurately image the sinus by CT is also preserved. This paper presents our preliminary experience with 18 mucoceles in which endoscopic sinus surgery was attempted. Five patients had preoperative proptosis and diplopia, three had Pott's puffy tumor and five had erosion of the posterior table of the frontal sinus. Fifteen patients were satisfactorily treated endoscopically, two lesions could not be satisfactorily approached and required external surgery, and one patient had persistent disease. No disease recurrence has been noted to date with endoscopic follow-up of up to 42 months.