A study on the predictive indicators for the recovery of spontaneous circulation in the early arterial blood gas analysis of cardiac arrest in the elderly

Objective@#The number of elderly patients in Korea has been on the rise recently, and hence the number of out-of-hospital cardiac arrest (OHCA) elderly patients is also rising. The causes of cardiac arrest for the elderly vary, and, it is difficult to predict the recovery of spontaneous circulation (ROSC) in OHCA patients. Therefore, the purpose of this study was to ascertain the predictive value of arterial blood gas analysis (ABGA) results in achieving ROSC in the elderly. @*Methods@#A retrospective analysis of emergency department patients with OHCA was performed at the Kangwon National University Hospital, Korea from 1 January 2016 to 31 December 2019. The initial ABGA results were compared between two patient groups, those who had achieved a return of spontaneous circulation and those who had not. Univariate and multivariable analyses were performed to elucidate the factors associated with ROSC. @*Results@#Overall, 229 OHCA patients were included in the final analysis. The lactate level was independently related to ROSC. A receiver operating characteristics (ROC) curve was plotted to obtain the best cutoff value. The lactate level <9.85 mmol/L showed the largest area under the ROC curve (AUC) to predict ROSC (AUC, 0.666; 95% confidence interval, 0.588-0.743). Multiple regression analysis was performed using the cutoff value, which was a lactate level of 9.85 (odds ratio, 2.907; 95% confidence interval, 1.432-5.902; P=0.003). @*Conclusion@#The ABGA results during the cardiopulmonary resuscitation of OHCA patients, showed that the lactate level was an independent factor associated with ROSC. The lactate cutoff value was 9.85 mmol/L.

A study on the predictive indicators for the recovery of spontaneous circulation in the early arterial blood gas analysis of cardiac arrest in the elderly

Objective@#The number of elderly patients in Korea has been on the rise recently, and hence the number of out-of-hospital cardiac arrest (OHCA) elderly patients is also rising. The causes of cardiac arrest for the elderly vary, and, it is difficult to predict the recovery of spontaneous circulation (ROSC) in OHCA patients. Therefore, the purpose of this study was to ascertain the predictive value of arterial blood gas analysis (ABGA) results in achieving ROSC in the elderly. @*Methods@#A retrospective analysis of emergency department patients with OHCA was performed at the Kangwon National University Hospital, Korea from 1 January 2016 to 31 December 2019. The initial ABGA results were compared between two patient groups, those who had achieved a return of spontaneous circulation and those who had not. Univariate and multivariable analyses were performed to elucidate the factors associated with ROSC. @*Results@#Overall, 229 OHCA patients were included in the final analysis. The lactate level was independently related to ROSC. A receiver operating characteristics (ROC) curve was plotted to obtain the best cutoff value. The lactate level <9.85 mmol/L showed the largest area under the ROC curve (AUC) to predict ROSC (AUC, 0.666; 95% confidence interval, 0.588-0.743). Multiple regression analysis was performed using the cutoff value, which was a lactate level of 9.85 (odds ratio, 2.907; 95% confidence interval, 1.432-5.902; P=0.003). @*Conclusion@#The ABGA results during the cardiopulmonary resuscitation of OHCA patients, showed that the lactate level was an independent factor associated with ROSC. The lactate cutoff value was 9.85 mmol/L.

Immunohistochemical Study of Collagenase-3(Matrix Metalloproteinase-13) in Squamous Cell Carcinomas of the Head and Neck / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Squamous cell carcinomas (SCCs) of the head and neck are known for their aggresive growth and propensity to metastasize, which often results in poor prognosis. Tumor cell interaction with the basement membrane has historically been viewed as the crucial step in tumor invasion and future metastasis. The invasive and metastatic process of malignant tumors requires the expression and activation of proteolytic enzymes which facilitate the progression of tumor cells in different ways. Among these proteolytic enzymes, collagenase-3 (matrix metalloproteinase-13) is a recently identified member of the MMP family, and is expressed in breast carcinomas and in articular cartilage from arthritic patients. The substrate specificity of MMP-13 is exceptionally wide as compared to other MMPs. MATERIALS AND METHODS: We performed immunohistochemical stains on 10 normal mucosas and 35 SCCs of the head and neck with anticollagenase-3 antibody and analysed the staining patterns. RESULTS: As a result, the expression of the MMP-13 were detected in 23 of the 35 SCCs (66%), but no expression was detected in any of the 10 normal mucosa. The expression of MMP-13 in most tumors was localized predominantly in neoplastic cells at the invading periphery of the tumor (74%;17/23). A significant correlation was found between MMP-13 expression and local tumor invasion but no correlation was observed between expression and the age, sex of the patients, histological grade, lymph node metastases, recurrence, or the stage of the tumors. CONCLUSION: These findings suggest that MMP-13 expression may contribute to the progression of a significant subset in SCCs of the head and neck. In the future, it is likely that elucidation of the regulatory mechanisms of the MMP-13 in SCCs may prove to be beneficial in developing novel therapeutic modalities for preventing invasion of these neoplastic cells.

Expression of Maspin in Squamous Cell Carcinoma of the Head and Neck / 대한이비인후과학회지

Squamous cell carcinomas (SCCs) of the head and neck are malignant tumors with their ability to invade and metastasis, which can affect the prognosis. The molecular pathogenesis of SCC of the head and neck is still not clear. Further understanding of the molecular alteration in SCC of the head and neck will be enable to provide more accurate and useful prognostic markers and more effective treatments. Maspin, a member of the serpin family of protease inhibitors, is known to have tumor-suppressor functions. However, association between its expression level and survival has not been demonstrated in Head and Neck cancer. Using the immunohistochemical technique to examine the expression levels of maspin in 30 cases of SCC in head and neck, the results showed that 73.3% of the cases expressed low to intermediate levels of maspin and 26.6% of the cases expressed high levels of maspin. The clinicopathological features of the SCC cases were also compared with the maspin expression level, and the results were that high maspin expression was significantly associated with the absence of lymph node metastasis. More importantly, higher maspin expression was significantly associated with better results of disease free survival time period, so it is suggested that high maspin expression may be a favorable prognostic marker for SCC of the head and neck.

Expresion of Collagenase-3 (Matrix Metalloproteinase-13) in human middle ear cholesteatoma and granulation / 대한이비인후과학회지

INTRODUCTION: Middle ear cholesteatoma is notorious for its capacity to absorb surrounding bone, but the exact mechanism of bone destruction is not fully understood until now. Recently, a group of matrix metalloproteinases (MMPs) were found to dissolve extracellular matrices. Among them, collagenase-3 (MMP-13), a newly found collagenase, is thought to be a strong enzyme to dissolve bone and cartilage. So we tried to find out whether Collagenase-3 is found in cholesteatoma and plays some role in bone destruction by cholesteatoma. MATERIALS AND METHOD: We performed immunohistochemical stains on 5 cholesteatomas, 5 middle ear granulations, 5 normal middle ear mucosa and 5 deep meatal skin specimens with anticollagenase-3 antibody and analysed the staining patterns. RESULTS: All the cholesteatomas showed strong immunoreactivity with collagenase-3. Two out of 5 granulations showed somewhat weaker and more disseminated patterns of immunoreactivity, but the rest 3 granulations showed no immunoreactivity. Normal middle ear mucosa and deep meatal skin specimens showed no immunoreactivity at all. CONCLUSIONS: Collagenase-3 may play an active role in the process of bone destruction by cholesteatoma; however, a further study using zymography or blotting method is needed to make this clear.

The value of salvage operation for recurrent head and neck cancer after surgery alone or surgery with radiotherapy / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Recurrent squamous carcinoma of head and neck carcinoma is not encountered infrequently. Surgical salvage is the most reasonable treatment for recurrence. The aim of the present review is to provide more information on the results and prognosis of surgical salvage after surgery alone or surgery with combined radiotherapy. MATERIALS AND METHODS: The operative salvage of recurrent head and neck carcinoma after surgery alone or surgery with combined radiotherapy was retrospectively studied in 18 patients treated between 1994 and 1999. Of the 18 patients in this retrospective review, there were 6 with local recurrence, 8 with regional recurrence, and 4 with stomal recurrence. RESULTS: The operative mortality was 16.6% and 72% of patients had one or more surgical complications. The 2-year crude survival rate in this series was 30% and the mean period of survival was 11.4 months. The 2-year survival rate were 33.3% for local recurrence and 50% for regional recurrence, and 0% for stomal recurrence. CONCLUSION: We concluded that surgical salvage had unsatisfactory results for patients with recurrent head and neck carcinoma after surgery alone or surgery with combined radiotherapy. Because of this low salvage rate, we should regard salvage surgery as palliative rather than therapeutic.

Effects of Platelet Activating Factor (PAF) on Cochlear Blood Flow in Guinea Pigs / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Platelet-activating factor (PAF) has been reported to be an active mediator of inflammation and ischemic damage in many organs. It plays a significant role in the pathogenesis of middle ear effusion. However, there have been few reports concerning the effects of PAF on inner ear and inner ear blood flow. This study determined the effects of PAF on the relation of cochlear blood flow (CBF) in guinea pigs. MATERIALS AND METHODS: The round window membrane (RWM) in each of 26 guinea pigs was exposed by dorsal approach and PAF was applied on it by Gelfoam pledgets. CBF of the basal turn was monitored using a laser Doppler flowmetry with the systemic blood pressure and changes in CBF being monitored, recorded and analysed. Epinephrine and normal saline were applied in the same manner as positive and negative controls, respectively. RESULTS: CBF was significantly reduced by the epinephrine application as a positive control. PAF applied at a concentration of 10 microgram/ml significantly increased CBF, while PAF applied at a concentration of 200 microgram/ml significantly reduced CBF. CONCLUSION: PAF did not induce ischemic damages when applied in the same concentration as the middle ear effusion fluid. However, when PAF was applied in excess, cochlear ischemia might be one of the mechanisms of inner ear damage it causes.

The Effects of Steroid and Steroid Receptor Blocker in Initial Polyp Formation / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: The epithelial rupture theory for the polyp formation has been well approved. According to Norlander et al., the polyp formation initiated by multifactorial pathophysiological events (infection/inflammation) appears to be a series of the consecutive events involving the rupture of epithelium, prolapse of lamina propria, epithelial ingrowth, microcavity formation, and finally the polyp formation. The purpose of this study is to determine the effects of steroid and steroid receptor blocker at the early stage of the polyp formation in a rabbit model. MATERIALS AND METHODS: In 20 New Zealand white rabbits, polyps were induced by epithelial damage with ostial occlusion. The mometasone and RU 486, given by the biodegradable film (polylactic acid), were used to investigate the possible effects of steroid and steroid receptor blockers. After one and three weeks, macroscopic polyps were counted postmortem and on histological slides after serial sectioning. RESULT: The polyp formation was significantly increased in the RU 486-treated group, whereas it was reduced in the mometasone-treated group. According to the alpha-actin immunohistochemistry, neovascularization at the margin of the initial polyp in the RU 486-treated group markedly increased compared with the mometasone-treated group. CONCLUSION: Steroid is thought to inhibit the initial polyp formation by reducing neovascularization particularly at the margin of initial polyp.

The Changes of the Generation of Superoxide Free Radical and the Activity of Antioxidant Enzymes after Streroid Therapy in Nasal Polyps / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: An intranasal topical and a systemic steroid therapy produce clinical improvement in patients with nasal polyps, but the mechanisms of their action are not clear. Recently, reactive oxygen species such as oxygen free radicals were identified as the potent toxic agents in various pathologic conditions including nasal polyps. The purposes of this study were to reveal the steroid effect on the generation of oxygen free radicals and exmaine the activities of various antioxidant enzymes in human nasal polyps. MATERIALS AND METHODS: Forty patients who received endoscopic sinus surgery due to chronic paranasal sinusitis with nasal polyps were classified into four groups; Group I included 10 specimens with no medication, group II included 10 specimens with oral steroid medication, Group III included 10 specimens with intranasal topical steroid therapy, group IV included 10 specimens with both oral and intranasal topical steroid therapy. We measured the generation of oxygen free radicals and activity of antioxidant enzymes, (SOD, GSH-Px, and CAT) and compared each group using electrophotometric analysis. RESULTS: The generation of oxygen free radicals were lowered in group II, III, and IV, compared to group I. Group IV showed the lowest level in the generation of oxygen free radicals. The activities of SOD, GSH-Px, and CAT, which are specific scavengers of oxygen free radicals, increased significantly in groups II, III, and IV (p<0.05). CONCLUSION: These results suggest that oxygen free radicals may play an important roles in the formation of nasal polyps. The mechanism of steroid action in the treatment of polyps may be explained in the decreased generation of oxygen free radicals and the increased activity of antioxidant enzymes in some ways.

Histologic Study on the Development of Olfactory Mucosa in Rats

BACKGROUND AND OBJECTIVES: There is evidence which suggests that mammals have functional olfactory systems at birth or shortly before birth. This study was performed to investigate perinatal development of the olfactory mucosa. MATERIALS AND METHODS: Sprague-Dawley rats at the 19th gestational day, and of the 1st, 3rd, 7th, 14th, 21st, and 28th postnatal day were sacrificed. The light microscopic investigation of the olfactory mucosa was conducted with hematoxylineosin stain, immunohistochemical stain for proliferating cell nuclear antigen (PCNA) and protein gene product (PGP) 9.5. RESULTS: Number of the cell layers, epithelial thickness, and density of the olfactory receptor cell peaked at the postnatal 14th day. The cells of the basal layer changed from globose cells to basal cell proper with age. The number of the basal cells to the receptor cells decreased with age. PCNA was positive both in the supporting and basal layers. PCNA positivity decreased with age in the supporting layer but stayed stationary in the basal layer. PGP 9.5 was strongly positive in the olfactory receptor cells, dendrites, and the nerve bundles but negative in the supporting and basal layers. CONCLUSION: The olfactory epithelium proliferated maximally at postnatal 14 day, and afterwards the olfactory mucosa tended to show their characteristic maturation with slowed neurogenesis.

Development of a Device Equipped with a Thermocouple for Measuring Nasal Airflow

BACKGROUND AND OBJECTIVES: To measure nasal cavity function as an airway, rhinomanometry and acoustic rhinometry are currently being used in clinical settings. However, these methods are not helpful for continuously measuring the aerodynamic status of both nasal cavities simultaneously. Therefore, a new instrument to evaluate the nasal flow is required. MATERIALS AND METHODS: To measure the airflow of bilateral nasal cavity simultaneously, two thermocouples are held in the headset, with the tips of thermocouples positioned below nostrils. The thermocouples are connected to the analog-digital converter and the digitized data is transferred to a notebook computer, in which a graphical programming language software is installed. Eighteen adults were recruited for this study who had no structural abnormality in their nasal cavities. For every subject, measurements from acoustic rhinometry, the thermocouple device, and rhinomanometry were taken in succession. The data from the thermocouple device was compared with those taken from the acoustic rhinometry and rhinomanometry. RESULTS: A negative correlation was noted between the minimum cross-sectional area by acoustic rhinometry and the inspiratory slope by thermocouple. No correlation was noted between the results for rhinomanometry and the thermocouple device. CONCLUSION: The thermocouple device has some advantages over other devices for its non-invasive, continuous, and real-time measurements and its ability to measure bilateral nasal cavity simultaneously.

Measurement of Nasal Trigeminal Pungency Threshold: Comparison between Normals and Patients with Decreased Sense of Smell

BACKGROUND AND OBJECTIVES: In order to measure the level of nasal trigeminal pungency threshold and to evaluate the interaction between olfactory and trigeminal nerves, we measured olfactory thresholds and trigeminal pungency thresholds using 1-butanol in 40 normal people and in 46 patients with decreased sense of smell by non-sinonasal origin. MATERIALS AND METHODS: Two-alternative forced-choice modified ascending method of limit (CCCRC test) was used for the measurement of olfactory and pungency thresholds, using 1-butanol plastic squeezable bottles successively threefold diluted by distilled water as stimulus, while distilled water as blank. RESULTS: There was a statistically significant difference in pungency threshold between normals (2.18+/-1.5 dilution step) and patients (1.11+/-1.0 dilution step)(p<0.001). CONCLUSION: The pungency thresholds of hyposmics and anosmics are higher than those of normals, which suggests that a loss or decrease of olfactory sensation is accompanied by a simultaneous decrease of trigeminal chemosensitivity.

Clinical Significance of Expression of Plasminogen Activatiors in Aural Cholesteatoma / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Bone destruction is characteristic of aural cholesteatoma. Plasminogen activator (PA), one of serine proteases, acts as the specific trigger in a proteolytic cascade, which may play a certain role in cholesteatomatous destruction. We investigated the relationship between the degree of PA expression and clinical severity of cholesteatoma. MAERIALS AND METHODS: Twenty six gerbilline cholesteatomas and 22 human cholesteatoma tissues were used. Immunohistochemical stainings were performed using antibodies against urokinase type-PA (u-PA) and tissue type-PA (t-PA), respectively. The degrees of expressions of both PAs were scored by a pathologist using a four step grading system of one negative to three positives, and were also objectively measured by an image analysis program using the black and white densitometry. Clinical stages in animal cholesteatoma and the presence of preoperative otorrhea, ossicular destruction, bone destroying complications, type and extent of cholesteatoma in a human group were used as clinical parameters in determing the disease severity. RESULTS: PA immunoexpressions were more intense in cholesteatoma than in normal skin, especially in suprabasal layer of the epithelium. The intensities of PA expression also increased as the stage of cholesteatoma became more advanced in an animal model. However, in human cholesteatoma, they didn't show any differences between the groups according to disease severity, although there was a difference of PA expression between the pars tensa and flaccida type cholesteatomas. CONCLUSION: PA may play a role in the pathogenesis, and possibly progression, of aural cholesteatoma.

Reconstruction after Mandibular Resection in Head and Neck Tumor / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Mandible resection for head and neck tumors causes disturbance of mastication, deglutition, articulation, and cosmesis. Therefore, proper mandibular reconstruction is very important for physiologic and esthetic restoration. The purpose of this study is to compare the various methods of mandibular reconstruction. MATERIALS AND METHOD: This study was comprised of 13 cases of mandibular reconstruction at Kangdong Sacred Heart Hospital, from March 1991 to December 1994. All cases were analyzed according to the causes, size and sites of mandibular resection, timing of mandibular reconstruction and the methods of mandibular reconstruction. RESULTS: The majority of patients (11 cases) in this series underwent primary reconstruction. Eight patients underwent free tissue transfer for reconstruction, with special 4 cases of iliac free flap and 3 cases of fibular free flap. CONCLUSION: Even though there are many methods of mandibular reconstruction, primary reconstruction with free flaps using fibular and iliac bone, in particular, are suited for oromandibular defect.

Prognostic Significance of Ki-67 Index and Expression of Cyclin D1 in Squamous Cell Carcinoma of the Larynx and Hypopharynx / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Various host and tumor parameters, particularly by the tumor size and lymph node metastasis have been studied in an attempt to evaluate and decide the optimal treatment of the patients with head and neck squamous cell carcinoma. However, it has been necessary that the prognostic parameters can be useful to evaluate the biological behaviors of the malignancy. The Ki-67 is a proliferative marker of tumor cells and cyclin D1 is a cell cycle regulator essential for G1 phase progression. Loss of regulation of cyclin D1 is likely to contribute to tumor development. The author evaluated the prognostic significance of cyclin D1 and Ki-67 in the carcinoma of larynx and hypopharynx to determine the relationship with the various clinicopathological parameters. MATERIALS AND METHODS: Paraffin embedded tissue specimens from 40 cases of squamous cell carcinoma of the larynx and hypopharynx were studied by immunohistochemical method using the Ki-67 and cyclin D1 antibody. K1-67 index and expression of cyclin D1 were compared with the recurrence, survival rate, disease free time and other clinicopathological parameters such as, primary site, pathologic differentiation, tumor stage and lymph node metastasis. RESULTS: The higher Ki-67 index was significantly correlated with poorer pathologic differentiation, and shorter disease free time. But there was no significant correlation between over expression of cyclin D1 and any factor for the head and neck cancer. However, the expression of cyclin D1 had a significant positive relationship with Ki-67 index (p<0.05). CONCLUSION: Ki-67 index is a good prognostic factors and cyclin D1 may be important in tumorigenesis for squamous cell cancer of the larynx and hypopharynx.

A Case of Jugular Bulb Injury by the External Ear Foreign Body / 대한이비인후과학회지

Foreign bodies of the external ear have been frequently encountered in the otolaryngological field. Recently, we experienced an interesting case of jugular bulb injury penetrating through the external auditory canal by an ear foreign body (woodswab), which was removed via mastoidectomy and facial recess approach. Immediately after removal of the foreign body, massive bleeding was followed and was controlled by SurgicelR packing and compression. Reporting this case, we suggest that special attention should be paid if the ear foreign body is associated with massive bleeding.

The Prevalence of Nasal Septal Deformities among Children in Kindergarten and First Grade in Anyang and Kunpo Cities

Nasal septal deformity (NSD) is a common nasal disorder, but its prevalence among children has not been reported in Korea. The aim of this work was to study the prevalence of NSD among children in kindergarten and first grade in Anyang and Kunpo cities and to evaluate whether the occurrence of NSD in children was affected by school activity or correlated with sex. We examined 1,646 nasal septa of 1,491 students (average age : 7.5 years ; range : 6.3-8.9 years) at three elementary schools and 155 children (average age : 6.5 years ; range : 5.9-7.1 years) at two public kindergartens. The overall prevalence of NSD was 13.6%. A significant difference in prevalence was found between male and female children and between male and female firstgraders. No difference was found between the children in kindergarten and the children attending first grade and between male and female children in kindergarten. The most common type of NSD, based on the Mladina's classification, was type 1, followed by types 2 and 5.

Selection of Olfactory Identification Items for Koreans / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: The olfactory identification test has been used in clinical assessment of olfactory ability for the following reasons: it is fast, it yields results compatible to a threshold test, and it gives a picture of how well the patient can deal with odors of everyday life. However, items in UPSIT (University of Pennsylvania Smell Identification Test)and CCCRC (Connecticut Chemosensory Clinical Research Center)identification test which are widely used in the world are selected for western people. Accordingly, these items in the tests are not appropriate for Koreans of different cultural background. MATERIALS AND METHODS: For the selection of proper items for the olfactory identification test, 42 natural odors familiar to Koreans were applied to 40 normal subjects and 40 patients with decreased sense of smell without sinonasal diseases. Among 42 items, 16 items with high identifiability and familiarity were chosen according to the results of test-retest in normal subjects. RESULTS: The results of olfactory identification test using 16 selected items showed high correlation with olfactory threshold. CONCLUSION: These 16 items can be used for an olfactory identification test for Koreans.

Anatomical Study of the Artery and the Nerve of the Thyroid Gland / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: An awareness of the surgical anatomy and the possible dispositions of the superior, recurrent laryngeal nerve and the thyroid arteries are very helpful in avoiding injury during thyroidectomy. MATERIALS AND METHODS: The relationship of the superior and recurrent laryngeal nerve to the superior and inferior thyroid artery and the incidence of the thyroid ima artery were studied in 43 adult cadavers. RESULTS: The superior thyroid artery (STA) arose commonly from the external carotid artery (59.3%). And the superior laryngeal nerve (SLN) was closely related to the STA. The inferior thyroid artery (ITA) arose commonly from the thyrocervical artery (81.4%) and eight different types of relationship between the ITA and the recurrent laryngeal nerve (RLN) were found. Among them, the most common type was the RLN which passed in front of the ITA (39.5%). And the incidence of the thyroid ima artery was 9.3%. CONCLUSION: The course and anatomic relationship of laryngeal nerve to the thyroid arteries is not constant, therefore careful identification of these structures should be performed during operation to decrease the surgical complications, such as vocal cord paralysis or hemorrhage.

The Factors Contributing to Hearing Gains after Chronic Ear Surgery: A Report from a Computerized Database / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: A computerized database system could provide benefit to reducing the variability of reporting results of chronic ear surgery, where a variety of factors may influence the outcomes. In the present study, the factors contributing to hearing gains after chronic ear surgery were investigated using a computerized database. MATERIALS AND METHODS: Audiometric data were easily drawn from the database log of 622 surgical cases of chronic otitis media done by one surgeon from 1989 to 1996. Of these, 309 were collected with the inclusion criteria being the period of no shorter than 3 months following tympanoplasty procedures. Post-operative hearing gains were compared according to the patient factor (sex, age), disease factors (unilateral vs bilateral disease, existence of cholesteatoma, preoperative otorrhea), surgery factor (primary versus revision operation, types of mastoidectomy, ossiculoplasty, hearing status of the operated ear), and the surgeon's experience. RESULTS: Pre- and post-operative air-bone gaps of the pure tone averages for the 309 cases studied were 34.6+/-13.4 dBHL and 24.9+/-13.8 dBHL, respectively. The post-operative hearing gains were 9.6+/-13.6 dBHL. The hearing gains did not differ significantly beween the groups when it is compared with regards to the factors, such as sex and age of patients, revision operation, hearing status, surgeon's experience. But the hearing gains differed with regards to the other factors, such as cholesteatoma, otorrhea, mastoidectomy and ossiculoplasty (p<0.05). CONCLUSION: This kind of computerized database is very useful to assess the effect of factors on the hearing gains following chronic ear surgery.