• KIPS Transactions on Software and Data Engineering
• /
• v.1 no.2
• /
• pp.109-114
• /
• 2012

Honeycombs are dense structures that small cysts, which generally have about 2~10 mm in diameter, are surrounded by the wall of fibrosis. When honeycomb is found in the patients, the incidence of acute exacerbation is generally very high. Thus, the observation and quantitative measurement of honeycomb are considered as a significant marker for clinical diagnosis. In this point of view, we propose an automatic segmentation method using morphological image processing and assessment of the degree of clustering techniques. Firstly, image noises were removed by the Gaussian filtering and then a morphological dilation method was applied to segment lung regions. Secondly, honeycomb cyst candidates were detected through the 8-neighborhood pixel exploration, and then non-cyst regions were removed using the region growing method and wall pattern testing. Lastly, final honeycomb regions were segmented through the extraction of dense regions which are consisted of two or more cysts using cluster analysis. The proposed method applied to 80 High resolution computed tomography (HRCT) images and achieved a sensitivity of 89.4% and PPV (Positive Predictive Value) of 72.2%.

• Tuberculosis and Respiratory Diseases
• /
• v.50 no.4
• /
• pp.415-425
• /
• 2001

Background : The correlation between the high resolution computed tomography(HRCT) emphysema score and the physiologic parameters including resting and exercise pulmonary function test was investigated in 14 patients($60.6{\pm}10.3$ years) with pulmonary emphysema. Methods : The patients underwent a HRCT, a resting pulmonary function test, and incremental exercise testing(cycle ergometer, 10 W/min). Computed tomography scans were obtained on a GE highlight at 10 mm intervals using 10 mm collimation, from the apex to the base after a full inspiration. The emphysema scores were determined by a CT program 'Density mask' outlining the areas with attenuation values less than -900 HU, indicating the emphysema areas, and providing an overall percentage of lung involvement by emphysema. Results : Among the resting PFT parameters, only the diffusing capacity(r=-0.75) and $PaO_2$ (r=-0.66) correlated with the emphysema score(p<0.05). Among the exercise test parameters, the emphysema score correlated significantly with the maximum power(r=-0.74), maximum oxygen consumption(r=-0.68), anaerobic threshold(V-slope method: r=-0.69), maximal $O_2$-pulse(r=-0.73), and the physiologic dead space ratio at the maximum workload(r=-0.80)(p<0.01). Conclusion: We could find that exercise testing parameters showed a much better correlation with the HRCT emphysema score, which is known to have a good correlation with the pathologic severity than the resting PIT parameters. Therefore it is suggested that exercise testing is superior to resting PIT for estimating in the estimation of the physiologic disturbance in emphysema patients.

• Tuberculosis and Respiratory Diseases
• /
• v.46 no.1
• /
• pp.65-74
• /
• 1999

Background : Open lung biopsy(OLB) has conventionally been regarded as the gold standard for the diagnosis in interstitial lung disease. With recent advances in diagnostic technique such as high resolution computed tomography(HRCT), and transbronchial lung biopsy(TBLB) which provide relatively accurate diagnosis of ILD, it is necessary to reevaluate the role of these methods in the diagnosis of ILD. Methods: We carried out a retrospective analysis of nineteen patients who underwent OLB at Dankook University Hospital for the diagnosis of acute and chronic ILD, between May 1995 and June 1998. By reviewing the medical records, the demographic findings, underlying conditions, HRCT and TBLB findings, OLB diagnosis, therapy after OLB, and complication of OLB were evaluated. Results: Thirteen patients(68.4%) had chronic ILD(symptom duration over 2 weeks prior to OLB), and six patients(31.6%) had acute ILD(symptom duration less than 2 weeks). Specific diagnosis were reached in 92%(12/13) of chronic ILD(5 bronchiolitis obliterans organizing pneumonia(BOOP), 2 constrictive bronchiolitis, 3 usual interstitial pneumonia, 1 hypersensitivity pneumonitis, 1 eosinophilic pneumonia), and in all patients of acute ILD(5 acute interstitial pneumonia, 1 pneumocystis carinii pneumonia). HRCT were performed in all patients and a correct first choice diagnosis rate of HRCT was 42%(5/12) in chronic ILD. In chronic ILD patients, 62%(8/13) received specific therapy(steroid therapy in 7 patients and moving in one patient), after OLB, but in acute ILD, all patients received specific therapy(steroid therapy in 5 patients and steroid and antibiotic therapy in one patient) after OLB. The in-hospital mortality after OLB was 5.3%(1/19). Conclusion: OLB is an excellent diagnostic technique with relatively low complications in patients with ILD. Therefore OLB should be considered in patients with ILD when the specific diagnosis is important for the treatment, especially in patients with acute ILD.

• Tuberculosis and Respiratory Diseases
• /
• v.42 no.6
• /
• pp.813-822
• /
• 1995

Background: Bronchial hyperresponsiveness and abnormal response such as a loss of distensibility are pathophysiologic characteristics if bronchial asthma. The only means of direct in vivo measurement of airway size had been a tantalium bronchography, until high-resolution computed tomography(HRCT) enabled to measure noninvasively two dimensional airway area more accurately and reliably. Method: To investigate airway area responses to bronchial provocation with methacholine and evaluate the major sites of bronchial constriction in patients with bronchial asthma. We examined HRCT scans in five patients with bronchial asthma who had significant bronchoconstriction(20% or more decrease in $FEV_1$) using CT scanner(5,000T CT, Shimadzu Co, Japan) before and in 3~5 min. after methacholine inhalation. Airways which were matched by parenchymal anatomic landmarks in each patient before and after methacholine inhalation were measured using film scanner(TZ-3X scanner; Truvel Co. Chatsworth CA, USA) and a semiautomated region growing method. Results: 1) We identified 9 to 12 airways in each patient which were matched by parenchymal anatomic landmarks before and after methacholine inhalation. 2) Airway responses to methacholine are quite different even in a patient. 3) The constriction of small airways(average diameter <2 mm; area < $3.14mm^2$) was 48.7%(8.3; SEM, n=43), being more prominant than that of large airways(average diameter >2 mm; area > $3.14mm^2$), 53.8% (4.4;SEM, n=10), but not significantly different(p>0.05). 4) There was no significant difference in the degree of constriction between upper(44.3% +5.8; mean + SEM, n=30) and lower lung regions(56.7% +4.5, n=23). Conclusions: Thus airway responses to methacholine bronchoprovocation is quite variable in a patient with bronchial asthma and has no typical pattern in patients with bronchial asthma.

• Journal of Chest Surgery
• /
• v.40 no.3 s.272
• /
• pp.215-219
• /
• 2007

Background: Due to the advancement of video assisted thoracoscopic techniques, an operation for primary spontaneous pneumothorax is now considered a common procedure. However, whether a preventive operation is necessary when a contralateral bulla is found on High Resolution Computed Tomography (HRCT) at the time of the first primary spontaneous pneumothorax attack is still unknown. In this retrospective study, it was our intension to find whether contralateral bullae are related to the occurrence of pneumothorax. Material and Method: Between January 1999 and April 2006, 550 patients were admitted to the Chungnam University hospital with primary spontaneous pneumothorax, which was confirmed by the HRCT scans in 190 patents. In these 190 patients, 159 had not received a bilateral operation after their first primary spontaneous pneumothorax attack. In these 159 patients, the relationship between the presence of contralateral bullae and the occurrence of pneumothorax was measured. Result: In these 159 patients, 67 had contralateral bullae confirmed inform the HRCT scan, and 92 had no visible contralateral bullae, During the follow up period, 6 patients (8.9%) with contralateral bullae had an occurrence of contralateral pneumothorax, and 5 patients (5.4%) without contralateral bullae had an occurrence of contralateral pneumothorax. (p=0.529 [Fisher's exact test]) Conclusion: In patients with unilateral primary pneumothorax, an HRCT scan is a useful way of confirming contralateral pulmonary bullae. However, the presence of bullae is not a significant predictive sign of an occurrence of contralateral pneumothorax. Also, surgery for pneumothorax is not completely uncomplicated, and bilateral surgery is still doubtful. A further prospective study will be required to find the relationship between the bullae found on HRCT and the occurrence of pneumothorax.

• Clinical and Experimental Pediatrics
• /
• v.45 no.3
• /
• pp.339-345
• /
• 2002

Purpose : The purpose of this study was to evaluate the clinical usefulness of chest high-resolution computed tomography(HRCT) in patients with chronic coughs or persistent wheezing with normal chest X-ray finding. Methods : We reviewed the charts, chest X-rays, and HRCT findings of patients with chronic coughs or persistent wheezing of less than 2 years of age. The records were sourced from the Department of Pediatrics, Inha University Hospital covering the period from July, 1999 to June, 2000. Chronic cough was defined as a cough which was prolonged for more than 3 weeks. Results : The sample consisted of 24 patients(male 15 and female 9, mean age $4.7{\pm}3.8$ months old). Among them, 16 patients showed normal findings(66.7%) and 8 patients showed abnormal (33.3%) in simple chest X-rays. Among 16 patients who had the normal chest X-rays, 13 patients showed abnormal chest HRCT findings(81.3%) such as air space consolidation of the dependent portion(62.5%), bronchiolitis obliterans(12.5%), and bronchopulmonary dysplasia(6.3%). Conclusion : We suggest that the chest HRCT is a useful diagnostic tool in the evaluation of patients with chronic cough or persistent wheezing with normal chest X-ray, especially below 2 years of age.

• Journal of Chest Surgery
• /
• v.37 no.5
• /
• pp.423-431
• /
• 2004

Background : Tumor size in lung cancer is not as good a prognostic factor for adenocarcinoma as it is for other types of lung cancer; therefore it is difficult to estimate the prognosis preoperative. However, there have recently been some reports on the radiologic findings correlating to the clinicopathologic prognostic factors in peripheral small adenocarcinoma of lung. We tried to evaluate the prognostic importance of High-Resolution CT (HRCT) findings of such adenoearcinoma, Material and Method: One houndred and seventy-six surgically resected small peripheral adenocarcinoma measuring 3 cm or less in greatest dimension were reviewed radiologically and clinicopathologically. Result: The patients with greater extent of ground-glass attenuation (GGA) had better clinico-pathological factors. The tumors with gross appearance of GGA or bubble-like shape showed better clinicopathological prognostic factors than scar-like or solid shape. Conclusion: HRCT findings of small peripheral adenocarcinomas of the lung correlated well with the histologic and clinical prognostic factors. We can predict the post-operative prognosis with the radiologic findings.

• 한국환경농학회:학술대회논문집
• /
• 2011.07a
• /
• pp.207-222
• /
• 2011

Relationships between soil saturated hydraulic conductivity ($K_s$) and porosity (${\phi}$) have been developed over many years; however, use of these relationships for evaluating rain-induced seals is limited mainly because of difficulties in estimating seal pore-size characteristics. The objectives of this study were to evaluate the $K_s$ of soil surface seals over a range of thicknesses, where seal thickness was determined using a High-Resolution-Computed-Tomography (HRCT) scanner, and to investigate relationships between $K_s$ and ${\phi}$ of developing seals in samples with equivalent diameters (e.d.) ${\geq}15\;{\mu}m$. A Mexico silt loam soil was packed to a bulk density (${\rho}_b$) of $1.1\;Mg\;m^{-3}$ in cylinders 160-mm i.d. by 160-mm long and subjected to $61-mm\;h^{-1}$ simulated rainfall having a kinetic energy (KE) of $25\;J\;m^{-2}\;min^{-1}$ for 7.5, 15, 30, and 60 min to create a range in seal development. Thicknesses of the seal layers were determined by analysis of HRCT images of seals. The $K_s$ values of the seals were estimated using an effective $K_s$ value ($K_{s-eff}$). The $K_s-{\phi}$ relationship was described by a Kozeny and Carmen equation, $K_s=B{\phi}^n$; where B and n are empirical constants and n = 31. This approach explained 86% of the variation between $K_s$ and ${\phi}$ within the soil seals. Knowledge of surface seal information and hydraulic conductivity can provide useful information to use in management of sites prone to sealing formation.

• Journal of the Korean Society of Radiology
• /
• v.82 no.4
• /
• pp.770-790
• /
• 2021

Idiopathic pulmonary fibrosis (IPF), based on the 2018 international clinical practice guidelines, can be diagnosed with a usual interstitial pneumonia (UIP) pattern on high-resolution computed tomography (HRCT) and compatible clinical findings. Given that imaging is pivotal for IPF evaluation and diagnosis, more emphasis should be placed on the integration of clinical, radiological, and pathologic findings for multidisciplinary diagnosis. Interstitial lung abnormality (ILA), on the other hand, has a purely radiological definition based on the incidental identification of CT abnormalities. Taken together, differentiation between ILA and clinically significant interstitial lung disease (ILD) must be based on proper clinical evaluation. With this review, the recent updates in IPF diagnosis and the radiologic considerations for ILA can be well understood, which can be helpful for the proper diagnosis and management of patients with diffuse interstitial pulmonary fibrosis.

• Tuberculosis and Respiratory Diseases
• /
• v.51 no.6
• /
• pp.597-602
• /
• 2001

A 47-years-old woman presented with a 2-month history of a dry mouth and dry cough. The patient had been taking medication for Sj$\ddot{o}$gren's syndrome for approximately 7 years. The chest radiography showed multiple cystic lesions and a hazy density in both lower lung fields. The HRCT showed a diffuse ground glass like appearance and multiple variable sized cystic lesions in both lung fields. After medication, the symptoms were aggravated. Bronchoscopy was preformed with a transbronchial lung biopsy. The biopsies showed an infiltration of lymphocytes, neutrophils, monocytes and histiocytes through the interstitial space of the alveola and a widening of the alveolar septa. However, the histological findings of the cysts were not obtained. Sj$\ddot{o}$gren's syndrome is a slowly progressive inflammatory autoimmune disease, which is characterized by lymphocyte mediated destruction of the exocrine glands, with pulmonary involvement in approximately 19-65%, High-resolution CT is a sensitive technique for assessing the pulmonary involvement in patients with Sj$\ddot{o}$gren's syndrome. Although a lung biopsy is not always necessary for establishing a diagnosis of an interstitial lung disease in Sj$\ddot{o}$gren's syndrome. A lung biopsy may reveal a wide spectrum of changes ranging from a mild inflammatory response to end stage fibrosis with honeycombing. Because of the predominantly peribronchiolar inflammatory infiltration and inspissated secretions the cysts were suspected to have been formed by the ball-valve phenomen. However, no definite evidence was obtained.