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H R Harnsberger

Publications and source records attributed to H R Harnsberger.

At least 19 recordsLinked to original sources

Electronic submission of academic works: a survey of current editorial practices of radiologic journals.

Computers are nearly ubiquitous in academic medicine, and authors create and compile much of their work in the electronic environment, yet the process of manuscript submission often fails to utilize the advantages of electronic communication. The purpose of this report is to review the submission policies of major academic journals in the field of radiology and assess current editorial practices relating to electronic submission of academic works. The authors surveyed 16 radiologic journals that are indexed in the Index Medicus and available in our medical center library. They compared the manuscript submission policies of these journals as outlined in recent issues of the journals and the corresponding worldwide web sites. The authors compared the journals on the following criteria: web site access to instructions; electronic submission of text, both with regard to initial submission and final submission of the approved document; text hardcopy requirements; word processing software restrictions; electronic submission of figures, figure hardcopy requirements; figure file format restrictions; and electronic submission media. Although the trend seems to be toward electronic submission, there currently is no clear-cut standard of practice. Because all of the journals that accept electronic documents also require a hardcopy, many of the advantages gained through electronic submission are nullified. In addition, many publishers only utilize electronic documents after a manuscript has been accepted, thus utilizing the benefits of digital information in the printing process but not in the actual submission and peer-review process.

Humans↗

Digital processing of radiographic images from PACS to publishing.

Several studies have addressed the implications of filmless radiologic imaging on telemedicine, diagnostic ability, and electronic teaching files. However, many publishers still require authors to submit hard-copy images for publication of articles and textbooks. This study compares the quality digital images directly exported from picture archive and communications systems (PACS) to images digitized from radiographic film. The authors evaluated the quality of publication-grade glossy photographs produced from digital radiographic images using 3 different methods: (1) film images digitized using a desktop scanner and then printed, (2) digital images obtained directly from PACS then printed, and (3) digital images obtained from PACS and processed to improve sharpness prior to printing. Twenty images were printed using each of the 3 different methods and rated for quality by 7 radiologists. The results were analyzed for statistically significant differences among the image sets. Subjective evaluations of the filmless images found them to be of equal or better quality than the digitized images. Direct electronic transfer of PACS images reduces the number of steps involved in creating publication-quality images as well as providing the means to produce high-quality radiographic images in a digital environment.

Analysis of Variance↗

Comparison of radiographic image quality from four digitization devices as viewed on computer monitors.

The objective of this study was to compare the quality of radiographic images digitized from commercial-grade and consumer-grade digital cameras and scanners as viewed on computer monitor. Radiographic images were digitized from hardcopy film using a commercial-grade laser scanner, a consumer-grade desktop flatbed scanner, a commercial-grade digital camera, and a consumer-grade digital camera. The quality of images without and with grayscale histogram adjustment was evaluated subjectively by 10 board-certified radiologists. Optical density response was evaluated objectively using a grayscale test pattern. There was no significant difference in subjective quality among images digitized with the commercial scanner, consumer scanner, and commercial camera. The quality of images digitized with the consumer camera was lower than the other 3. Objective tests showed the commercial scanner to have the most linear optical density response. For the purpose of viewing images on a computer monitor, a consumer-grade desktop scanner can produce images of similar quality to those produced by more expensive laser commercial-grade scanners and digital cameras and provides cost-efficient means to digitize radiographic plain films. A consumer-grade camera may not be optimal for use in this setting.

Analysis of Variance↗

Accessory salivary tissue in the mylohyoid boutonnière: a clinical and radiologic pseudolesion of the oral cavity.

BACKGROUND AND PURPOSE: Though classically depicted as a continuous muscular barrier between the sublingual and submandibular spaces, the mylohyoid muscle is often discontinuous. These areas of discontinuity may contain fat, blood vessels, salivary tissue, or combinations thereof that may be mistaken both clinically and radiologically for pathologic abnormalities. We sought to demonstrate the prevalence and radiologic appearance of dehiscence of the mylohyoid muscle. METHODS: One hundred axial, contrast-enhanced CT studies of the neck, obtained over a 10-month period, were retrospectively reviewed. Inclusion criteria included 3-mm-thick slices and absence of pathologic abnormalities or surgical changes in the oral cavity. Scans were assessed for the presence and contents of mylohyoid defects such as accessory salivary tissue, defined as nonlymphoid tissue within defects in the mylohyoid, having attenuation and enhancement characteristics similar to those of orthotopic sublingual and submandibular salivary tissue. RESULTS: Mylohyoid defects were identified in 77 of 100 individuals. The deficiencies were bilateral in 67% and unilateral in 33%. Accessory salivary tissue was identified in 37 of 100. Fat and blood vessels were commonly identified within the mylohyoid defects. Sixty-one percent of the defects contained only fat. Thirty-five percent of the defects contained blood vessels. CONCLUSION: Deficiencies in the mylohyoid muscle were visible in 77% of individuals who underwent scanning. The defects may contain fat, blood vessels, salivary tissue, or all three characteristics. Accessory salivary tissue was identified in 37% of individuals who underwent scanning. Recognition of mylohyoid deficiencies and the typical appearance of accessory salivary tissue will allow accurate diagnosis of this benign, anatomic variant.

Adipose Tissue↗

Causes of unilateral sensorineural hearing loss screened by high-resolution fast spin echo magnetic resonance imaging: review of 1,070 consecutive cases.

OBJECTIVE: Evaluation of the ability of screening high-resolution, nonenhanced, fast spin echo (FSE) T2-weighted magnetic resonance imaging (MRI) of the internal auditory canal (IAC) and cerebellopontine angle (CPA) to detect nonacoustic schwannoma causes of unilateral sensorineural hearing loss (SNHL). FSE-MRI is equally sensitive in detecting acoustic (vestibular) schwannoma as gadolinium-enhanced MRI, but sensitivity to other causes of hearing loss is unknown. STUDY DESIGN: Retrospective review of screening FSE-MRI studies. SETTING: Academic otology/neurotology and neuroradiology practices. PATIENTS: There were 1,070 patients with unilateral SNHL who underwent radiologic screening for retrocochlear pathology. RESULTS: Normal findings were found in 944 cases. Typical (acoustic) vestibular schwannoma were found in 56 patients. Seventy additional lesions were identified: 27 CPA lesions, 29 inner ear lesions, and 12 intraaxial lesions including 9 infarctions, 1 multiple sclerosis case, 1 mesial temporal lobe sclerosis, and 1 colloid cyst. CONCLUSIONS: High-resolution T2 FSE-MRI of the IAC and CPA is a highly sensitive screening tool for unilateral SNHL, which can detect a variety of lesions in addition to vestibular schwannomas. To our knowledge in 2 years of follow-up in these patients screened for IAC/CPA lesions, no other lesions causing SNHL have been found. High-resolution FSE screening technique, used in conjunction with appropriate clinical prescreening and referral, can provide an equally sensitive method of evaluating unilateral SNHL compared to gadolinium-enhanced T1 MRI while reducing costs and providing distinct advantages in evaluating nonacoustic schwannoma causes of SNHL.

Adult↗

The CT and MR imaging features of carcinoma arising in thyroglossal duct remnants.

BACKGROUND AND PURPOSE: Carcinoma arising in thyroglossal duct remnants is a well-described entity in the pathology and surgery literature, but it has little recognition in the radiology literature. Preoperative diagnosis may alter surgical management, although this diagnosis is rarely made. This study was undertaken to determine the radiologic features that might differentiate carcinoma from benign thyroglossal duct cysts. METHODS: Twenty-one cases of nonpediatric thyroglossal duct anomalies imaged at our institution during a 15-year period were reviewed retrospectively. The images were assessed for lesion wall thickness, enhancement, soft-tissue component, calcification, and loculation of the cystic component. Three additional cases of thyroglossal duct carcinoma obtained from outside institutions were reviewed for these features also. RESULTS: Six cases of thyroglossal duct carcinoma were reviewed. All cases of carcinoma had solid soft-tissue elements visible on CT scans or MR images, compared with three of 18 cases of benign thyroglossal duct cysts. The malignant component was seen as a small peripherally based mass in relation to a cyst, a solid mass in the expected course of the thyroglossal duct, or a complex invasive mass also in the midline of the neck. CT only revealed calcification in cases of carcinoma, within either the primary carcinoma mass or a metastatic node. CONCLUSION: Thyroglossal duct carcinoma should be suspected in an adult patient in the presence of a solid nodule or invasive features in association with a thyroglossal duct lesion visible on CT scans or MR images. The presence of calcification, which is seen best on CT scans, may be a specific marker for carcinoma.

Adult↗

Preoperative cochlear implant imaging: is magnetic resonance imaging enough?

OBJECTIVE: To investigate the accuracy of magnetic resonance imaging (MRI) as a preoperative imaging technique for cochlear implant candidates. STUDY DESIGN: Retrospective, blinded. SETTING: Tertiary medical center. PATIENTS: 31 cochlear implant candidates with various causes of hearing loss. INTERVENTION: Cochlear implant patients received preoperative high-resolution temporal bone computed tomography (CT), and high-resolution T2-weighted fast spin echo MRI (FSE-MRI). The images were read independently of each other and in a blinded manner by two neuroradiologists. The imaging results were also correlated with intraoperative findings. MAIN OUTCOME MEASURES: Lack of agreement between the findings for either imaging technique; also, lack of agreement between imaging findings and intraoperative findings. RESULTS: FSE-MRI is equal to CT imaging in the detection of abnormalities of cochlear patency. It is better than CT imaging in detecting cochlear dysplasia and large vestibular aqueducts, and in determining the presence of the cochlear nerve. CONCLUSION: FSE-MRI is accurate in predicting inner ear anomalies and obstruction of the cochlear lumen. It also adds information not gathered from CT imaging, such as the presence and size of the cochlear nerve.

Cochlear Implantation↗

MR evaluation of vestibulocochlear anomalies associated with large endolymphatic duct and sac.

BACKGROUND AND PURPOSE: Large endolymphatic duct and sac (LEDS) is one of the most common anomalies seen in patients with congenital sensorineural hearing loss (SNHL), and is known to occur with other inner ear findings. Our purpose was to use high-resolution T2-weighted fast spin-echo (FSE) MR imaging to describe the features and prevalence of specific anomalies that occur in association with LEDS. METHODS: We retrospectively reviewed MR images of the inner ear obtained in 63 patients with LEDS and in 60 control subjects. We evaluated each image for features of cochlear and vestibular dysplasia, including deficiency of the cochlear modiolus, gross cochlear dysmorphism, asymmetry of the cochlear scalar chambers, enlargement of the membranous vestibule, gross vestibular dysmorphism, and abnormality of the semicircular canals (SCC). RESULTS: Cochlear anomalies were present in 76% of ears with LEDS. Modiolar deficiency, gross dysmorphism, and scalar asymmetry were seen in 94%, 71%, and 65% of abnormal cochleas, respectively. Vestibular abnormalities were present in 40% of ears with LEDS. Simple enlargement, gross dysmorphism, and distortion of the lateral SCC were seen in 84%, 16%, and 32% of abnormal vestibules, respectively. CONCLUSION: Coexistent cochlear anomalies, vestibular anomalies, or both are present in most ears with LEDS, and appear as a spectrum of lesions, ranging from subtle dymorphism to overt dysplasia. The presence of coexistent anomalies in LEDS affects treatment decisions and prognosis. Newer techniques of high-resolution FSE MR imaging provide a means of exquisite characterization of LEDS, as well as more sensitive detection of associated vestibulocochlear anomalies.

Cochlea↗

The temporal bone. Contemporary diagnostic dilemmas.

The entire topic of temporal bone imaging cannot be addressed in a single article. This article discusses the clinical areas in which there have been particularly important advances: inflammatory disease, sensorineural hearing deficit, pulsatile tinnitus, facial nerve dysfunction, and the postoperative temporal bone. The common thread linking those sections is an attempt to emphasize their pitfalls.

Bone Diseases↗

Ultra high resolution nonenhanced fast spin echo magnetic resonance imaging: cost-effective screening for acoustic neuroma in patients with sudden sensorineural hearing loss.

The financial burden for the evaluation of patients for acoustic neuroma in an otolaryngology practice is substantial. Patients with sudden sensorineural hearing loss represent a portion of that population seen with unilateral, asymmetric auditory symptoms who require investigation for acoustic neuroma. For these patients, gadolinium-enhanced magnetic resonance imaging is the diagnostic gold standard. Auditory brain stem response testing has been used in the past as a screening test for acoustic neuroma, but its apparent sensitivity has fallen as the ability to image smaller acoustic neuromas has improved. Fast spin echo magnetic resonance imaging techniques without gadolinium have been shown to be as effective in the detection of acoustic neuroma as contrast-enhanced magnetic resonance imaging. Limited nonenhanced fast spin echo magnetic resonance imaging now provides an inexpensive alternative for high-resolution imaging of the internal auditory canal and cerebellopontine angle. Fast spin echo magnetic resonance imaging can now be done at a cost approximating auditory brain stem response testing while providing the anatomic information of contrast-enhanced magnetic resonance imaging. Cost analysis was done in the cases of 58 patients with sudden sensorineural hearing loss by comparing the costs for routine workup and screening of acoustic neuroma with the cost of fast spin echo magnetic resonance imaging with the use of screening protocols based on literature review. The potential cost savings of evaluating patients with sudden sensorineural hearing loss with fast spin echo magnetic resonance imaging for acoustic neuroma was substantial, with a 54% reduction in screening costs. In an era of medical economic scrutiny, fast spin echo magnetic resonance imaging has become the most cost-effective method to screen suspected cases of acoustic tumors at our institution by improving existing technology while reducing the cost of providing that technology and eliminating charges for impedance audiometry, auditory brain stem response testing, and contrast-enhanced magnetic resonance imaging.

Acoustic Impedance Tests↗

'Leave me alone' lesions of the petrous apex.

PURPOSE: When troublesome MR imaging findings are noted in the petrous apex, the radiologist must determine if the area in question needs surgical therapy. Two nonsurgical entities, asymmetric fatty marrow and fluid-filled petrous air cells (trapped fluid), can be noted on conventional brain MR images and confused with pathologic lesions. Our observation that radiologists do not always confidently define the nonsurgical petrous apex lesions precipitated this investigation. METHODS: Twenty-three patients with either asymmetric fatty marrow (six) or unilateral effusion in a pneumatized petrous apex (17) on MR images were studied. Eighteen patients underwent high-resolution temporal bone CT. For all patients, the medical charts were reviewed retrospectively and/or the surgical and clinical follow-up findings were reviewed with the referring physician. RESULTS: In the patients with asymmetric fatty marrow, MR signal intensity followed fat on all sequences. The questioned apex in the patients with trapped fluid showed mixed MR signal characteristics (low to high T1 signal, high T2 signal). CT scans confirmed nonexpansile air-cell opacification. CONCLUSION: Asymmetric fatty marrow in the petrous apex and petrous air-cell effusions have characteristic MR and CT features that facilitate their correct diagnosis. Effusions with intermediate or high T1 signal are most frequently confused with cholesterol granulomas. In those patients, long-term CT follow-up may be helpful to confirm their stability.

Adipose Tissue↗

Terson syndrome: CT evaluation in 12 patients.

PURPOSE: Terson syndrome may be overlooked in the acute setting and often requires ophthalmologic intervention to prevent long-term visual loss. In this syndrome, vitreous or retinal hemorrhage results from an abrupt rise in intracranial pressure, leading to retinal venous hypertension and intraocular hemorrhage. Our objective was to determine whether imaging findings could be discovered that might facilitate an earlier diagnosis. METHODS: Our inpatient medical record data base for 1991-1996 listed 11 patients with Terson syndrome. The medical records of these 11 patients were reviewed retrospectively and compared with their noncontrast head CT scans and with scans of 10 control subjects. One additional case was discovered prospectively, for a total of 12 patients. Three radiologists unaware of the patients' history evaluated CT scans of the orbits for evidence of intraocular hemorrhage. RESULTS: CT findings in eight patients were suggestive of retinal hemorrhage manifested by a retinal crescent or nodule that was slightly hyperdense relative to the vitreous humor. There was a high degree of concordance between the retrospective and independent reviews. CONCLUSION: Retinal nodularity and crescentic hyperdensities are evident on CT scans in the majority of patients with Terson syndrome. Although findings are subtle and not present in all cases, in the setting of subarachnoid hemorrhage they suggest retinal hemorrhage and warrant detailed fundoscopic evaluation.

Adolescent↗

Surgical exposure of the petrous internal carotid artery: practical application for skull base surgery.

When exposing the horizontal petrous carotid artery in preparation for intrapetrous carotid bypass, the surgeon has no definite landmarks to localize the perimeter of the cochlea. The results of this study provide a practical, consistent, and safe method to maximize carotid artery exposure while minimizing cochlear injury. We measured the carotid-cochlea distance (mean, 4.3 mm) and the carotid-cochlear angle (mean, 10.8 degrees) in 33 temporal bones in which the extended middle fossa approach had been performed. We correlated this distance to the width of a Sheehy weapon knife, which can be easily measured intraoperatively. Twenty-five temporal bones were imaged prior to surgical exposure using a new computed tomography (CT) protocol that can be used for preoperative assessment of the carotid-cochlear anatomy. The carotid-cochlea distance and carotid-cochlear angle measured on CT are compared with postsurgical measurements.

Cadaver↗

Large vestibular aqueduct syndrome: a genetic disease?

OBJECTIVE: Our objective was to determine the familial incidence of large vestibular aqueduct syndrome (LVAS) detected by CT and MR imaging and to propose the genetic inheritance of LVAS. MATERIALS AND METHODS: We retrospectively reviewed cases of LVAS revealed by temporal-bone CT and MR imaging at the University of Utah Health Sciences Center. We interviewed 25 patients with LVAS regarding family history of hearing loss. Any family members with onset of hearing loss before 30 years old also underwent CT and MR imaging. The vestibular aqueduct (on CT scans) or the endolymphatic duct (on MR images) was measured at the midpoint of the distal limb. A measurement greater than 1.5 mm in diameter was considered abnormally large. Diagnosis of LVAS was made if the patient had hearing loss and positive imaging findings. RESULTS: Of the 25 patients, five were found to have familial involvement, resulting in subsequent study of eight additional symptomatic individuals. A total of 33 patients had positive CT or MR imaging findings. Twenty-nine underwent both studies, two underwent CT only, and two underwent MR imaging only. Among the 33 patients with LVAS, 39% familial occurrence was observed (13 patients). In four of the five different families, the involvement occurred among siblings in one generation. In one of the five families, the involvement occurred in two generations, affecting an uncle and a cousin of the patient. CONCLUSION: In patients with LVAS, a significant subgroup had familial involvement. Based on the pedigrees of the familial cases, the pattern was most consistent with autosomal recessive inheritance, although a smaller component of autosomal dominant or multifactorial inheritance may exist.

Deafness↗

Overlapping thin-section fast spin-echo MR of the large vestibular aqueduct syndrome.

PURPOSE: To evaluate a high-resolution, thin-section fast spin-echo MR imaging technique of the inner ear to identify the large vestibular aqueduct syndrome seen on temporal bone CT scans. METHODS: We retrospectively reviewed the temporal bone CT scans of 21 patients with hearing loss and enlarged bony vestibular aqueducts by CT criteria. High-resolution fast spin-echo MR imaging was then performed on these patients using dual 3-inch phased-array receiver coils fixed in a temporomandibular joint holder and centered over the temporal bones. MR imaging included axial and oblique sagittal fast spin-echo sequences. The diameter of the midvestibular aqueduct on CT scans and the signal at the level of the midaqueduct on MR images were measured on axial sequences, then compared. High-resolution MR imaging with the same protocol was performed in 44 control subjects with normal ears, and similar measurements were taken. RESULTS: The average size of the enlarged bony vestibular aqueduct on CT scans was 3.7 mm, and the average width of the signal from within the enlarged aqueduct on MR images was 3.8 mm. Statistical analysis showed excellent correlation. MR images alone displayed the enlarged extraosseous endolymphatic sac, which accompanies the enlarged aqueduct in this syndrome. Five ears in three patients with enlarged bony vestibular aqueducts on CT scans showed no evidence of an enlarged endolymphatic duct or sac on MR images. An enlarged endolymphatic sac was seen on MR images in one patient with a bony vestibular aqueduct, which had normal measurements on CT scans. MR imaging alone identified a single case of mild cochlear dysplasia (Mondini malformation). In the 88 normal ears studied, the average size of the endolymphatic sac at its midpoint between the common crus and the external aperture measured on MR images was 0.8 mm (range, 0.5 to 1.4 mm). In 25% of the normal ears, no signal was seen from within the vestibular aqueduct. CONCLUSION: Thin-section, high-resolution fast spin-echo MR imaging of the inner ear is complementary to CT in studying patients with the large vestibular aqueduct syndrome, as MR imaging better displays the soft tissue and fluid of the membranous labyrinth.

Adolescent↗

"Pneumofornix" (air under the eyelid): a normal finding.

Normal pockets of air under the eyelids have not been previously described in the literature. To assess the incidence and patterns of normal air bubbles in the region of the eyelid, computed tomography (CT) scans of 126 normal orbits and 36 orbits of patients with thyroid orbitopathy were assessed. Twenty-eight (22%) of the normal orbits and 14 (39%) of the thyroid orbits had a well-defined medial or lateral air bubble (or both) on axial views (.1 > P > .05). Oval central or paracentral air bubbles in sections through the superior or inferior fornix were seen in 19 (15%) of the normal orbits and 10 (28%) of the thyroid orbits (.1 > P > .05). It is important to be aware of the incidence and patterns of these normal air bubbles to ensure their accurate differentiation from pathologic air bubbles.

Adolescent↗