Imaging features of rhinoplasty.

SUMMARY: Cosmetic rhinoplasty encompasses a diverse group of procedures, including alteration of the radix, nasal dorsum, nasal tip, and nasal base; premaxillary augmentation; septoplasty; and combinations thereof. Similarly, many different types of grafts and alloplastic materials can be used in cosmetic rhinoplasty, such as cartilage, bone, silicone, porous polyethylene, expanded polytetrafluoroethylene, and calcium hydroxylapatite. Complications of rhinoplasty that can be observed on imaging include retained metallic surgical instrument fragments, infection, implant extrusion, nerve impingement by implants, nasal valve collapse, and implant deformity. Knowledge of the basic surgical procedures and potential complications of cosmetic rhinoplasty is important for adequately interpreting postoperative radiologic imaging studies.

Imaging of cosmetic facial implants and grafts.

SUMMARY: A wide variety of implants and grafts have been used for cosmetic facial surgery, including forehead, nose, cheek, lip, and chin augmentation. Some of the implant materials include silicone, expanded polytetrafluoroethylene (Gore-Tex), hydroxylapatite, and porous polyethylene (Medpor). Grafts include bone and cartilage, which can be prepared as "Turkish Delight" for rhinoplasty. Imaged facial implants and grafts can be encountered incidentally or purposely to evaluate complications. Many of these materials have distinct radiologic imaging features and should not be misinterpreted as pathology. Conversely, implant complications should be appropriately recognized by using a focused imaging approach. The purpose of this article was to review the different types of cosmetic facial implants and grafts with an emphasis on their expected and complicated radiologic imaging appearances.

Imaging features of midface injectable fillers and associated complications.

Injectable fillers are increasingly used for midface augmentation, which can be performed for facial rejuvenation and treatment of HIV facial lipoatrophy. A variety of temporary and permanent filler agents has been developed, including calcium hydroxylapatite, collagen, liquid silicone, polytetrafluoroethylene, hyaluronic acid, poly-l-lactic acid, and polyacrylamide gel. Facial fillers are sometimes encountered on radiologic imaging incidentally and should not be mistaken for pathology. Alternatively, patients with facial fillers may undergo imaging specifically to evaluate associated complications, such as infection, overfilling, migration, foreign-body reaction, and scarring. Therefore, it is important to be familiar with the imaging appearances of the various filler materials and their complications.

Increased corneal temperature caused by MR imaging of the eye with a dedicated local coil.

To determine the existence of tissue heating-associated risks to the eye with magnetic resonance (MR) imaging performed at high specific absorption rates (SARs), corneal temperature was measured in 14 patients immediately before and after MR imaging performed with a 1.5-T, 64-MHz unit and a quadrature-driven body coil for radio-frequency transmission and a receive-only local coil designed for eye imaging. Fast spin-echo pulse sequences were used predominantly. Estimated peak SARs ranged from 3.3 to 8.4 W/kg. A statistically significant (P < .001) increase in average corneal temperature (32.2 degrees C +/- 0.7 before imaging, 33.1 degrees C +/- 0.6 after) was associated with MR imaging of the eye. The changes in corneal temperature ranged from 0.2 degrees to 1.8 degrees C (average, 0.9 degrees C). The highest corneal temperature measured after MR imaging was 35.1 degrees C. MR imaging performed with a dedicated local coil at the SARs studied produced elevations in corneal temperature that were physiologically inconsequential and below the temperature threshold (41 degrees to 55 degrees C) for radio-frequency radiation-induced cataractogenesis.

Occlusion and narrowing of the pharyngeal airway in obstructive sleep apnea: evaluation by ultrafast spoiled GRASS MR imaging.

Morphologic abnormalities of the pharyngeal airway are frequently found in patients with obstructive sleep apnea. These structural alterations in the pharyngeal airway can be detected in awake patients by using rapid imaging techniques. Ten patients with clinically proved obstructive sleep apnea had ultrafast spoiled gradient-recalled acquisition in the steady state (GRASS) MR imaging of the pharyngeal airway to determine the presence of occlusions and/or narrowings. Twelve sequential images were obtained at one midsagittal plane and at eight transverse planes through the pharyngeal airway. The scans were obtained at the rate of one image per 1.04 sec while the patient was breathing quietly. Occlusions or narrowings of the pharyngeal airways were detected on MR images in all patients. The site(s) of the occlusions and the site(s) and extent of the narrowings varied. Six patients had occlusions and four had narrowings of one or more sites. This study shows that ultrafast spoiled GRASS MR imaging can be used to evaluate patients with obstructive sleep apnea during tidal breathing and is useful for determining the presence of occlusions and narrowings of the pharyngeal airway.

Beneficial effect of indapamide in experimental myocardial ischemia.

Indapamide, a nonthiazide chlorosulfamoyl diuretic, which possesses well-known antihypertensive properties, is able to scavenge free radical intermediates involved in lipid peroxidation. In this respect, it has almost the same level of action as alpha-tocopherol. Using an isolated working rat heart preparation, we investigated the effect of indapamide on the myocardial resistance to global total normothermic ischemia followed by reperfusion. The heart, isolated at the end of chronic oral pretreatment (7 day at 3 mg/kg body weight/day), was submitted to ischemia for 15 min and then reperfused. The main results were as follows: in the indapamide-treated group, 1) postischemic recovery of cardiac function was significantly better as compared to the untreated control group; 2) lactate dehydrogenase (LDH) release measured after 15 min of reperfusion was significantly reduced; 3) the myocardial content of organic hydroperoxides (HPO), taken as an index of lipid peroxidation, was significantly lowered, whereas the activity of superoxide dismutase (SOD) and glutathione peroxidase (GPx) remained unchanged; and 4) electron spin resonance (ESR) analysis of coronary effluents, collected during the first minutes of reperfusion in the presence of the spin-trap 5,5-dimethyl-1-pyrroline N-oxide (DMPO), revealed a significant modification in the treated group. These findings suggest that indapamide treatment is able to afford some protective effect to cardiac tissue during the early stage of postischemic reperfusion, and that this effect might be related to the antioxidant properties of inadapamide.

Dynamic study of the upper airway with ultrafast spoiled GRASS MR imaging.

Dynamic magnetic resonance (MR) imaging of the upper airway was not possible previously because of poor temporal resolution. Recently, a rapid technique has been developed that provides the means to obtain multiple images at different section locations with sufficient image quality and temporal resolution to allow a comprehensive, dynamic study of the upper airway. The authors describe an ultrafast spoiled GRASS (gradient-recalled acquisition in the steady state) pulse sequence for dynamic studies of the upper airway. The authors believe that this procedure has potential for identifying and characterizing upper airway abnormalities such as nonfixed occlusions and/or narrowings that may exist in patients with obstructive sleep apnea.

Aneurysmal bone cyst of the paranasal sinuses associated with fibrous dysplasia: CT and MR findings.

An aneurysmal bone cyst (ABC) in the paranasal sinuses is rare with only four previous cases having been described in the sphenoid and ethmoid sinuses. This report describes a case of an ABC involving the sphenoid and ethmoid sinuses as well as the upper nasal fossae. It is currently believed that a preexisting primary bone lesion, such as fibrous dysplasia, initiates an osseous arteriovenous fistula, which creates a secondary reactive lesion of bone, the ABC. These lesions, which are comprised of multiple cysts containing liquid blood and serous fluid, are optimally studied by a combination of CT and MR scans.

Metallic otologic implants: in vitro assessment of ferromagnetism at 1.5 T.

MR imaging is contraindicated for patients with certain ferromagnetic implants because of potential risks related to movement or dislodgement. This is especially true for metallic implants located in sensitive areas of the body, such as those placed in and around the ear. Therefore, the ferromagnetic qualities of 35 different metallic otologic implants were assessed by placing them individually on a millimeter scale in a plastic petri dish that was slowly moved into the center of a 1.5-T MR imaging system. None of the metallic otologic implants moved during this procedure. The results demonstrate that each of these implants are made from nonferromagnetic materials and do not pose a risk to patients undergoing high-field-strength MR imaging. These data effectively expand the list of metallic implants that appear to be safe for MR imaging.

Normal CT anatomy of the paranasal sinuses.

The role and technique of CT in the evaluation of the paranasal sinuses are discussed. CT scans of normal patients in axial and coronal planes are presented. A brief discussion of the normal morphology and development of the paranasal sinuses is included.

Dysphagia and Forestier disease.

Forestier disease (ankylosing hyperostosis) is a well-recognized and common disease entity. Although these patients rarely have complaints related to their spine, they are seen by the otorhinolaryngologist because of dysphagia, since the osteophytic spurs may impinge on the posterior pharyngeal wall. Since the plain roentgenogram and barium swallow is so specific, biopsy examination of the pharyngeal mass is not necessary.

Acupuncture needles: a "new" foreign body in the ear.

With the recent popularity of acupuncture therapy and anesthesia in the United States, patients are having temporary needles placed in the external ear. These matallic radiopaque needles appear on routine skull and mastoid examinations. This article is written to familiarize radiologists with this ""new'' iatrogenic foreign body.

The inclined lateral projection: a new view in temporal bone tomography.

Radiographic findings in the inclined lateral projection are presented. This view provides detail of the malleus and incus which is not provided on any other view and also preserves the visualization of temporal bone anatomy seen by routine lateral projection. The frequent occurrence of ossicular pathology in inflammatory and traumatic diseases of the ear requires the meticulous radiographic examination of the ossicles provided by this projection. Patient positioning is uncomplicated and comfortable.