High-Resolution Numerical Simulation of Respiration-Induced Dynamic B₀ Shift in the Head in High-Field MRI

PURPOSE: To demonstrate the high-resolution numerical simulation of the respiration-induced dynamic B0 shift in the head using generalized susceptibility voxel convolution (gSVC). MATERIALS AND METHODS: Previous dynamic B0 simulation research has been limited to low-resolution numerical models due to the large computational demands of conventional Fourier-based B0 calculation methods. Here, we show that a recently-proposed gSVC method can simulate dynamic B0 maps from a realistic breathing human body model with high spatiotemporal resolution in a time-efficient manner. For a human body model, we used the Extended Cardiac And Torso (XCAT) phantom originally developed for computed tomography. The spatial resolution (voxel size) was kept isotropic and varied from 1 to 10 mm. We calculated B0 maps in the brain of the model at 10 equally spaced points in a respiration cycle and analyzed the spatial gradients of each of them. The results were compared with experimental measurements in the literature. RESULTS: The simulation predicted a maximum temporal variation of the B0 shift in the brain of about 7 Hz at 7T. The magnitudes of the respiration-induced B0 gradient in the x (right/left), y (anterior/posterior), and z (head/feet) directions determined by volumetric linear fitting, were < 0.01 Hz/cm, 0.18 Hz/cm, and 0.26 Hz/cm, respectively. These compared favorably with previous reports. We found that simulation voxel sizes greater than 5 mm can produce unreliable results. CONCLUSION: We have presented an efficient simulation framework for respiration-induced B0 variation in the head. The method can be used to predict B0 shifts with high spatiotemporal resolution under different breathing conditions and aid in the design of dynamic B0 compensation strategies.

Efficient Experimental Design for Measuring Magnetic Susceptibility of Arbitrarily Shaped Materials by MRI

PURPOSE: The purpose of this study is to develop a simple method to measure magnetic susceptibility of arbitrarily shaped materials through MR imaging and numerical modeling. MATERIALS AND METHODS: Our 3D printed phantom consists of a lower compartment filled with a gel (gel part) and an upper compartment for placing a susceptibility object (object part). The B0 maps of the gel with and without the object were reconstructed from phase images obtained in a 3T MRI scanner. Then, their difference was compared with a numerically modeled B0 map based on the geometry of the object, obtained by a separate MRI scan of the object possibly immersed in an MR-visible liquid. The susceptibility of the object was determined by a least-squares fit. RESULTS: A total of 18 solid and liquid samples were tested, with measured susceptibility values in the range of −12.6 to 28.28 ppm. To confirm accuracy of the method, independently obtained reference values were compared with measured susceptibility when possible. The comparison revealed that our method can determine susceptibility within approximately 5%, likely limited by the object shape modeling error. CONCLUSION: The proposed gel-phantom-based susceptibility measurement may be used to effectively measure magnetic susceptibility of MR-compatible samples with an arbitrary shape, and can enable development of various MR engineering parts as well as test biological tissue specimens.

Correlation between Anterior Inferior Cerebellar Artery Loop and Otologic Symptoms / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: The correlation of anterior inferior cerebellar artery (AICA) vascular loop around cerebellopontine angle (CPA) and otologic symptoms remains controversial. The objective of this study was to evaluate the relationship of the anatomical type of AICA loop and otologic symptoms according to the findings of 3-dimensional Fourier transformation constructive interference in steady state (3DFT-CISS) MRI. SUBJECTS AND METHOD: 316 ears from 165 patients were included in this study. Otologic symptoms and the results of pure tone audiometry, auditory evoked potential, and electronystagmography were checked by retrospective chart review. AICA loops were classified by its configuration on 3DFT-CISS MRI. According to their extension depth in internal auditory canal (IAC), the loops were classified as type I (lying within CPA), type II (from porus acusticus to 50% of the length of IAC), and type III (extending beyond 50% of IAC). In addition, the loops were classified as S (small) and L (large) by comparing the thickness of the loop with adjacent facial nerve. RESULTS: The predominant type of AICA loop was type I (62.0%) and type S (72.8%). Ears with type III loop presented significantly higher rate of hearing impairment than those with type I or II. There were no significant differences in pure tone threshold, hearing loss in 3 consecutive frequencies, canal paresis, and AEP latencies among 3 AICA types classified with the depth of the loop. Ears with type S AICA loop showed significantly higher rate of hearing impairment, elevated threshold, hearing loss in 3 consecutive frequencies, and canal paresis than those with type L loop. CONCLUSION: The small diameter of AICA loop had significant association with hearing impairment and otologic test abnormalities. Impaired blood flow through the vascular loop and resultant hypoperfusion of inner ear may be the pathophysiologic mechanism of vestibulocochlear nerve compression syndrome.

Changes of Taste Function after Tonsillectomy / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: The objective of the study was to investigate changes in taste sensation after tonsillectomy by using filter paper discs (FPD )method and visual analogue scale (VAS ). MATERIALS AND METHOD: Thirty healthy adult patients who had undergone tonsillectomy were included in this study. A taste test using the FPD method and a subjective rating of taste function based on VAS were performed preoperatively and postoperatively on the 14th day. Serum zinc level was checked at the operation day. Operative findings regarding adhesion, size, and inflammation were recorded. RESULTS: Four patients (13.3%)showed 2 points above the elevated taste identification threshold (TIT). Nine patients (30%)felt their taste sensitivity decreased more than 2 points in the VAS system after the operation. At the postoperative 2 week period, there were significant decrease in sensitivity to sweet and salty TIT, tendency to decrease in sour TIT, and tendency to increase in bitter TIT. The mean VAS decreased significantly. The changes in TIT (dTIT )to each taste stimuli and the changes of VAS (dVAS) had no significant correlation. The degree of adhesion, size and inflammation of the tonsil and serum zinc level showed no significant correlation with dTIT to each taste stimuli and dVAS. CONCLUSION: At 2 weeks after tonsillectomy, the taste sensitivity generally increased except for bitter stimuli. But this changes were not correlated with subjective taste assessment, which may be due to various postoperative discomforts. Tonsil adhesion, size, inflammation and serum zinc level did not influence acute postoperative changes in taste function.

A Case of Taste Distortion and Phantogeusia after Tonsillectomy / 대한이비인후과학회지

Dysgeusia after tonsillectomy is a rare complication and there have been a few reports in the literature. The most possible cause of this complication is thought to be direct or indirect injury to the glossopharyngeal nerve or its lingual branch. Other suggested causes are lack of dietary zinc and habitual drug intake. We report a 51-year-old man, who presented severe parageusia and phantogeusia following tonsillectomy that was performed for chronic tonsillitis. The surgery was performed by electrocautery dissection without identifiable injury to the glossopharyngeal nerve. Dysgeusia developed 3 weeks after the operation and he complained loss of appetite and significant weight loss. He did not take any drug habitually that could affect his sense of taste. His serum zinc level (48 microgram/dl, normal range : 61-121 microgram/dl) was decreased. We prescribed a mineral supplement containing vitamin B complex and therapeutic dose of zinc. Eight months after the operation, his taste function was not recovered and he still retained problems related to diet. This case indicates that a patient should be informed of the risk of postoperative taste disturbance after tonsillectomy as being one of the rare complications.

Acoustic Rhinnometric Accessment of Nasal Cavity in Normal Neonates / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Acoustic rhinometry, introduced by Hilberg in 1989, is an important investigative tool in rhinology. It should be well suited for studies of the nasal cavities of infants and children in whom nasal airway is more important than in adults. The main objective of this study was to find normal data of nasal cavity dimension in Korean full-term normal neonates. SUBJECTS AND METHOD: Between March 2003 and November 2003, the nasal airways of 100 normal full-term neonates (56 males; 44 females) were examined by acoustic rhinometry (Rhinometrics) and miniprobe. MCA (minimal cross-sectional area), TMCA (total MCA), DMCA (distance from the nostril to the position of MCA) and TVOL40 (sum of volume of the anterior 40 mm of the nasal airway) were calculated. RESULTS: The mean values of TMCA, DMCA and TVOL40 were 0.220 cm2 0.944 cm, 1.716 cm3 respectively. CONCLUSION: Acoustic rhinometry is quick to perform, non-invasive, and it requires minimal co-operation and has no adverse effects. Nasal airway evaluation in neonates is significant in this age group, but limitations in equipment make this difficult. Further studies are required for more accurate evaluation of the nasal airway of neonates and infants.

The Effect of Superior Cervical Ganglionectomy on Recovery of Olfaction in Induced Anosmic Mice / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: This study was undertaken to evaluate the effect of superior cervical ganglionectomy (SCG) on anosmia, which is peripherally induced in the mice. MATERIALS AND METHOD: Three groups of mice (BCF1) were studied: normal control (nasal instillation of saline, n=6); zinc sulfate group (nasal instillation of 64 mM zinc sulfate, n=25); SCG group (superior cervical ganglionectomy after nasal instillation of 64 mM zinc sulfate, n=25). Tissues of olfactory mucosa were obtained at 1, 2, 3, 4 and 7 weeks after instillation of zinc sulfate, and processed for immunohistochemistry using antisera to olfactory marker protein (OMP) to evaluate the olfactory regeneration. RESULTS: No OMP-positive cells were observed in the first two weeks after the instillation of zinc sulfate in both zinc sulfate group and the SCG group. However, the OMP-positive cells appeared first at 3 weeks after the instillation in both groups, and gradually increased in number at 4 and 7 weeks. In the SCG group, the increase of OMP-positive cells was significantly greater than those of the zinc sulfate group. The number of OMP-positive cells in the SCG group at 7 weeks was almost similar to that of the normal control group. CONCLUSION: SCG enhances regeneration of olfactory receptor cells at 3 weeks after injury. It was inferred from the above results that SCG has a significant effect on the regeneration of olfactory receptor cells and we suggest that SCG could be an effective treatment modality for olfactory dysfunction.

Expression of Protease-activated Receptor 2 in Nasal Polyp: Immunohistochemical Study / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Protease-activated receptor 2 (PAR-2) has been known to play an important role in modulating homeostasis and inflammation in the airways. But only a little is known about the localization of PAR-2 in nasal mucosa and relationship between PAR-2 and nasal mucosal inflammation. In this study, we investigated the localization of PAR-2 in nasal polyp and turbinate mucosa and examined the relationship between the PAR-2 expression and eosinophil infiltration. MATERIALS AND METHOD: Nasal polyp tissues were obtained from 20 nasal polyposis patients and inferior turbinate tissues were taken from 12 nasal septal deviation patients as control. PAR-2 expression was assessed by immunohistochemical staining. We compared PAR-2 immunoreactivity between nasal polyp and turbinate mucosa. Infiltrated eosinophils were counted ands its correlation with the intensity of PAR-2 immunoreactivity in nasal polyp was determined. Also, we evaluated the PAR-2 expression in the presence of allergic rhinitis. RESULTS: PAR-2 immunoreactivity was detected in the nasal mucosal epithelium, endothelial cells, vascular myocytes, submucosal glands, fibroblasts and inflammatory cells. PAR-2 expression was similar between nasal polyp and turbinate mucosa, but inflammatory cells of nasal polyp showed stronger immunoreactivity than those of turbinate. Immunoreactivity in inflammatory cells showed correlation with eosinophil infiltration in nasal polyp. There were no differences in the PAR-2 expression between allergic rhinitis patients and non-allergic rhinitis patients. CONCLUSION: Increased expression of PAR-2 in inflammatory cells of nasal polyp and its correlation with eosinophil infiltration raise the possibility that PAR-2 may play a role in pathophysiology of nasal polyposis.

Comparison of Midazolam with and without Nalbuphine for Intravenous Sedation in Nasal Surgery / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Effective and safe premedication in nasal surgery is very important in nasal surgery under local anesthesia. We investigated the effects of preoperative administration of midazolam only and midazolam combined with nalbuphine HCl for nasal surgery under local anesthesia. SUBJECTS AND METHOD: A total of 30 patients presenting for nasal surgery under local anesthesia were randomly assigned. Patients in the midazolam group (n=15) received single administration of midazolam and subjects in the nalbuphine group (n=15) were injected nalbuphine in addition to midazolam. Cardiovascular and respiratory status were monitored continuously. Questionnaires were given to the operator and the patients, and the scores were compared statistically. RESULTS: Operator's assessment indicated better pain control gain in the nalbuphine group. The other parameters in the operator's assessment and the patient's assessments were not statistically significant between the two groups. No adverse cardiovascular and respiratory side effects were noted, but pruritus was observed more frequently in the nalbuphine group. CONCLUSION: Better pain control gain was indicated only by the surgeon for the nalbuphine group, but there was no additional advantage in other parameters of combining nalbuphine with midazolam. We concluded that a single preoperative administration of midazolam would be effective enough and serve as a safe method for simple nasal surgery.

Nasal Septal Deviation and Compensated Inferior Turbinate Hypertrophy / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Septoplasty with or without turbinate surgery is performed by many otorhinolaryngologists. However, the surgical methods largely rely on clinical judgement alone. The purpose of this study is to investigate the correlation between deviated nasal septum and inferior turbinate with compensatory hypertrophy on paranasal sinus computed tomography (CT) and to suggest a guideline for septal and turbinate surgery. SUBJECTS AND METHOD: Paranasal sinus CT scans of twenty patients with nasal septal deviation and compensatory hypertrophy of inferior turbinate were taken and reviewed. Measurements of thickness of mucosa and medial conchal bone, projection angle of inferior turbinate, distance between medial conchal bone and lateral nasal line, and interval between median line and conchal bone were obtained. Each measurement was compared with that of opposite side of nasal cavity and normal control subjects. RESULTS: The thickness of medial mucosa and conchal bone of inferior turbinate of concave side were more increased than those of the other side (p<0.05). The projection angles of conchal bone from lateral nasal wall in each side were different and the distances between medial conchal bone and lateral nasal line were more increased in concave side (p<0.05). CONCLUSION: Septoplasty and concomitant inferior turbinate surgery that manipulates conchal bone and soft tissue is necessary for the patients with a complaint of nasal obstruction. Reduction of medial mucosa and out-fracture of hypertrophied inferior turbinate are proper for the concomitant inferior turbinate surgery. The data gathered using CT images are important in making a decision regarding turbinate surgery in septoplasty.

Anatomic Variations of Sphenoid Sinus and Related Neurovascular Structures: A Study of CT Analysis / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Anatomic variations of the sphenoid sinus and the related neurovascular structures are common. Because it is a rule that may complicate surgery in such a place, these variations should be known preoperatively. The aim of this study was to delineate the relationship between the pneumatization of the sphenoid sinus and the related neurovascular structure variations including carotid artery and optic nerve. SUBJECTS AND METHOD: A review of 100 paranasal sinus tomographic scans was made to investigate the anatomic variations of the sphenoid sinus and the related structures. The analyzed items were the pneumatization of the sphenoid bone including anterior clinoid process (ACP) and pterygoid process (PP), the relationship between the pneumatization of the sphenoid sinus and the incidence of bulging of the internal carotid artery (ICA), optic nerve (ON), maxillary nerve and pterygoid nerve. The patterns of intersinus septum and accessory septum were also assessed. RESULTS: The most prevalent type of the pneumatization of the sphenoid sinus was the sellar type (90%). Midline location of the septum was found in 32 patients. Accessory septum was found in 52 patients. The bulging of ICA into the sphenoid sinus was found in 52 patients (retrosellar segment) and 67 patients (presellar segment). ON bulging was found in 52 patients. Patients showing pneumatization of ACP and PP were 20 and 34, respectively. There was a statistically significant relationship between the pneumatization of ACP, PP and the bulging in ICA and ON. Number of patients showing bulging of the maxillary nerve and pterygoid nerve was 36 and 49, respectively. CONCLUSION: Accurate evaluation of the pneumatization of the sphenoid sinus and the variations of the related neurovascular structures is possible with preoperative CT scans of the sinus. Numerous variations of the related neurovascular structures are related with degrees of pneumatization of the sphenoid sinus. For safe sphenoid sinus surgery, a thorough analysis of the preoperative CT scans as well as the precise anatomic knowledge is required.

Effect of Inhibitor of TNF-alpha and Oxatomide on Experimental Immune Mediated Otitis Media with Effusion / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Local immune response, one of the pathogenesis of middle ear effusion (MEE) is associated with the development and persistence of effusion in the middle ear cavity and inflammatory mediators play a major role in the production of MEE. The purpose of this study was to determine the effects of TNF-alpha antagonist and oxatomide on the outcome of immune mediated otitis media with effusion (OME) in rats. MATERIALS AND METHOD: Otitis media was induced by injecting KLH (Keyhole lympet hemocyanin) transtympanically 7 days after systemic immunization. Phosphate-buffered saline solution was used as control. Other groups were pretreated with TNF-alpha antagonist (soluble TNF receptor type I, sTNF RI) or oxatomide respectively before transtympanic injection of KLH. Seventy-two hours after the transtympanic injection, temporal bones in each group were examined histopathologically and vascular permeability of the middle ear mucosa was measured by the Evans blue vital dye technique. RESULTS: In the KLH, sTNF RI and oxatomide groups, MEE was developed in 83%, 0%, 66% of the ears, respectively. The oxatomide group and sTNF RI group showed significant decrease in inflammation, mucosal thickening and vascular permeability as compared with KLH group and those parameters of sTNF RI group showed lower values than those of oxatomide group. CONCLUSION: Transtympanic administration of sTNF RI and oxatomide appears to suppress the development of immune mediated OME. In terms of inhibiting MEE, sTNF RI was more effective than oxatomide. This study suggests that TNF-alpha antagonist and oxatomide may have a adjunctive role in the treatment and prevention of otitis media with effusion.

Effect of Rofecoxib on Pain and Hemorrhage after Tonsillectomy / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Nonsteroidal anti-inflammatory durgs (NSAIDs) are now widely accepted analgesics for posttonsillectomy patients, but their ability to inhibit platelet cyclooxygenase (COX) may be associated with a risk of increased bleeding after tonsillectomy. Rofecoxib, the recently introduced selective COX-2 inhibitor, may have advantages for analgesics in tonsillectomy in that they produce minimal effects on platelet aggregation. But the analgesic efficacy of rofecoxib in tonsillectomy has not been made known yet. The aim of our randomized prospective study was to compare the analgesic efficacy of rofecoxib, the selective COX-2 inhibitor, and ibuprofen, the classic NSAID, for the posttonsillectomy pain management. We also evaluated the influence of both drugs on the posttonsillectomy bleeding. SUBJECTS AND METHOD: Thirty-eight adult patients undergoing tonsillectomy were randomly divided into either ibuprofen or rofecoxib group. Patients received either oral ibuprofen (600 mg, three times a day) or oral rofecoxib (25 mg, twice a day). Patients recorded pain levels twice daily for 7 days using a visual analogue scale. Posttonsillectomy hemorrhage was recorded in each groups. RESULTS: Pain scores for the 7 days were not significantly different between two groups, but the rofecoxib group reported less pain. Rofecoxib group felt more satisfactorily about early control of postoperative pain. There was no significant difference in the incidence of postoperative hemorrhage between two groups. CONCLUSION: Rofecoxib is as effective as ibuprofen for postoperative pain control in adult tonsillectomy, which might be beneficial for avoiding the adverse effects of NSAIDs.

A Case of Parotid Abscess due to Candida Glabrata / 대한이비인후과학회지

The parotid gland is the most commonly infected salivary gland. Parotid abscess occurs mostly in elderly persons who are debilitated by systemic illness. Staphylococcus aureus and anaerobic bacteria are mostly cultured in aspirates of pus from parotid abscess. We report a case of a parotid abscess that grew Candida glabrata on culture after fine-needle aspiration biopsy. This organism has not been previously associated with this condition.

Expression of Inducible Nitric Oxide Synthase and Its Steroid Effect in TDI-Induced Nasal Hyperreactive Guinea Pigs / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Nitric oxide (NO) in exhaled air is elevated in allergy. Topical corticosteroid therapy which has been shown to reduce airway inflammation is associated with reduction in exhaled levels of NO in allergy. The aim of this study is to investigate the induction of inducible nitric oxide synthase (iNOS) and the effect of steroid on the expression of iNOS in the nasal mucosa of TDI (toluene diisecyanate)-induced nasal hyperreactive guinea pig. MATERIALS AND METHODS: We developed an allergy model in guinea pigs using the intranasal application of TDI, We evaluated the iNOS expression and in vivo effects of triamcinolone on the expression of iNOS and infiltration of eosinophil in TDI-sensitized guinea pigs by immunohistochemical stain. RESULTS: Nasal symptoms were significantly suppressed and the number of eosinophils in the nasal mucosa were significantly inhibited by the treatment of triamcinolone. Immunoreactivity to iNOS was localized to ciliated cells of epithelium, vascular endothelial cells, secretory cells of nasal glands and some inflammatory cells in the mucosa of the control group. High expression of iNOS in the nasal mucosa of the TDI-sensitized group was demonstrated, and it was suppressed by triamcinolone therapy. CONCLUSION: These results show that increased expression of iNOS may contribute to allergic inflammation and the antiinflammatory effect of steroid in allergy is partly mediated by the reduction of iNOS expression.

A Case of Fibrous Dysplasia of the Ethmoid Bone Forming Intracranial Cyst / 대한이비인후과학회지

Fibrous dysplasia is a benign bone lesion characterized by the replacement of the normal substances of the interior of the bone by fibroosseous connective tissue histologically exhibiting varying degrees of osseous metaplasia. Craniofacial dysplasia represents approximately 2.5% of all bone tumors and 7.5% of benign bone tumors. Craniofacial dysplasia frequently affects the maxilla and frontal bone and induces local facial swelling and exophthalmos. The dysplasia has predilection for membranous bone such as femur or tibia, so its origin in the ethmoid is very rare. Recently, we experienced a case of fibrous dysplasia originating in the ethmoid bone extending to intracranial region. Our case demonstrated a huge bony lesion involving right ethmoid, frontal and sphenoid bone and extending to the left frontal area extensively forming a large dumbbell shaped cyst with thin calcified wall. There are no reported cases of fibrous dysplasia forming huge cyst in the intracranial region internationally. Hence, we report a case of fibrous dysplasia of ethmoid sinus forming the intracranial huge cyst.

Three Dimensional Fourier Transformation Constructive Interferencein Steady State Magnetic Resonance Imaging (3DFT-CISS MRI) ofthe Inner Ear in Patients with Sensorineural Hearing Loss / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Three dimensional fourier transformation constructive interference in steady state magnetic resonance imaging (3DFT-CISS MRI) allows fast and precise imaging of the inner ear structures and provides excellent cerebrospinal fluid-nerve contrast within the internal auditory canal and cerebellopontine angle. This study was performed to delineate the inner ear structure in patients with sensorineural hearing loss (SNHL) using 3DFT-CISS MRI and to evaluate the correlation between structural abnormality and clinical symptoms of the affected ear. MATERIALS AND METHODS: Fourteen patients with sensorineural hearing loss were studied using 3DFT CISS axial and coronal MRI scans of both ears. We observed the visualization of the inner ear structures and measured them individually. The radiological measurements were analyzed to compare the findings in non-affected ears with those in affected ears of SNHL patients. In addition, the onset of symptoms was also evaluated for any relationship to their MR findings. RESULTS: The inner ear structures including cochlea, semicircular canal, vestibule, and cranial nerve VII, VIII were precisely visualized. There was statistically no difference in the measurements of the inner ear structures between affected and non-affected ears in patients with sudden SNHL. However, statistically significant differences in the width and height of the vestibule were observed in the affected ears between sudden SNHL and idiopathic chronic SNHL. CONCLUSION: 3DFT-CISS MRI allows detailed study of the normal and pathologic inner ears. Therefore, this MR technique can be a useful method as a routine protocol in the study of the inner ear diseases.

Hearing Loss in Patients with Chronic Renal Failure with Hemodialysis Treatment / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Hemodialysis (HD) is a valid treatment modality in patients with chronic renal failure, but it has been noted as a possible cause of hearing impairment. There have been many efforts to elucidate the etiologic factors of hearing impairment in patients with chronic renal failure (CRF) with HD. But, there were no identified causes of hearing impairment. This study was undertaken to determine the correlating factors and the degree and types of hearing impairment in patients with CRF with HD treatment. MATERIALS AND METHODS: We studied clinical status of 46 patients (92 ears) with CRF with HD treatment about hearing threshold, blood level of hemoglobin, blood urea nitrogen (BUN), parathyroid hormone (PTH), b2-microglobulin, duration of HD, and erythropoietin treatment between August, 1998 and October, 1998 at hemodialysis room, Uijongbu St. Mary's Hospital. RESULTS: The 33 patients (60 ears) had hearing loss, and 15 patients (22 ears) among them had clinically significant hearing loss. In hearing loss group, 31 patients showed the sensorineural type, one conductive type, and one mixed type. There was no significant correlation between the degree of hearing impairment and duration of HD, level of hemoglobin, BUN, PTH and beta2-microglobulin. The group of CRF with diabetes mellitus (DM) showed high incidence of clinically significant hearing impairment. Erythropoietin treatment was negatively correlated with hearing impairment. CONCLUSION: DM was a probable cause of hearing impairment and treatment of anemia with erythro-poietin administration seemed to be a possible preventing factor.

A Study for Causative Diseases of Globus Pharyngeus Patients Who Have NoPathologic Conditions in Laryngopharynx / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Globus pharyngeus is the feeling of a lump or foreign body in the throat. Otolaryngologists are often confronted with this condition, and some authors report that it represents 3 percent of all new clinic referrals. Unfortunately, we still do not completely understand the etiologies of globus pharyngeus, but there are recently increasing evidences to link the globus symptoms with various diseases. MATERIAL AND METHODS: We selected 32 globus patients, who exhibited no pathologic condition in physical examinations, and were analysed by general work up, barium esophagogram, 24 hour-ambulatory double-probe pH monitoring, esophageal manometry test, Fuchs' series, and MMPI. RESULTS: The results were as follows, gastroesophago-laryngopharyngeal reflux disease (n=15: 46.9%), various psychotic problems (n=11: 34.4%), esophageal motility disorders (n=7: 21.9%), duodenal ulcer (n=2: 6.3%), Eagle's syndrome (n=2: 6.3%), and hiatal hernia (n=1: 3.1%). In 5 cases, we couldn't find the etiology of globus pharyngeus. CONCLUSION: Globus pharyngeus patients, who had no pathologic findings in layrnx and pharynx, might have laryngopharyngeal-gastroesophageal reflux diseases and psychologic problems.

Histopathologic Distribution of Fibers and Glands in Nasal Polyps / 대한이비인후과학회지

The purpose of this study is to investigate the distribution and the direction of fibers in nasal polyps. The distribution of fibers is not well known about position and quantity. From June 1993 to April 1996, the authors obtained 232 nasal polyps from 191 patients. The polyps had been stained with H-E method. Authors observed the histopathologic type of polyps, and then the polyps have been stained with Weigert's method getting information about the fibers of polyps. In the polyps, the origin site of polyp showed dense collagen fibers of which direction resembled the movement of sand in hour-glass. In the submucosa, the direction of fibers is parallel to epithelium. Each gland or grouped glands in the polyps were circumscribed with collagen fibers. Our current study on the fibers and glands in nasal polyps is very fundamental, but we suggest that further investigation about the fibers and glands in polyps would enable to reveal pathogenesis of polyp investigated.