Biomedical subjects

Seok-Soo Byun

Publications and source records attributed to Seok-Soo Byun.

27 records · Page 2Linked to original sources

PubMed2005

Laparoscopic nephrectomy for congenital benign renal diseases in children: comparison with adults.

AIM: To compare the results of laparoscopic nephrectomy for congenital benign renal diseases in children and adults. METHODS: From August 1996 to February 2003, laparoscopic nephrectomies were performed on 26 children and 60 adults. Of these patients, 33 patients (17 children, 16 adults) with comparable diseases were included in the analysis. RESULTS: Disease was on the right side in 16 patients and on the left in 17. Operative and convalescence parameters, including operative time, blood loss, transfusion rate, conversion rate to open surgery, resumption of oral intake, hospital stay, and complication rate, were evaluated in both groups. Median operative time in the paediatric group was 140 min compared to 147.5 in adults (p=0.626). The estimated blood loss was significantly different (median 25 and 75 cm(3) in children and adults, respectively; p<0.001). Other operative and convalescence parameters were not statistically different. However, whereas no child required a blood transfusion, three adults (18.8%) did. No major perioperative complications occurred in the paediatric group, but open surgical exploration was needed due to retroperitoneal bleeding in a single adult. CONCLUSION: Our findings indicate that laparoscopic nephrectomy for congenital benign disease in children is achieved safely and that the modality offers additional advantages in children as compared to adults.

Adult↗

PubMed2005

Subjective pain scale and the need for analgesia during shock wave lithotripsy.

OBJECTIVE: To investigate patients' opinions on the degree of pain during shock wave lithotripsy, and the need for analgesics in patients with urinary stone. METHODS: A prospective questionnaire study involving subjective pain assessment during and just after shock wave lithotripsy was performed in consecutive patients with uncomplicated renal or ureteral stones. The patients were given unbiased information on the analgesics prior to the procedure. Ten minutes after beginning shock wave lithotripsy, the degree of pain was rated by the patient using a 10-point visual analog scale. After the procedure, the patients were asked to complete a self-administered questionnaire. Based on the response for the questionnaire, the patients were divided as 'tolerable' or 'non-tolerable' group. RESULTS: The results from 180 patients (males 113, females 67) with a mean age of 50.0 +/- 13.0 were analyzed. The average subjective pain score was 6.6 +/- 2.3 during the procedure, and 70 (38.9%) patients responded that they were able to tolerate the pain without analgesics. A total of 116 (64.4%) patients did not agree that analgesic should be recommended to other patients. Subjective pain score during the procedures was not affected by laterality, size of stone, level of education or socioeconomic status, but was affected by patient age (p = 0.042), sex (p = 0.012) and location of stone (p = 0.014). Right and kidney stones were significantly higher in the 'non-tolerable' group than in the 'tolerable' group (p = 0.003 and p = 0.011, respectively), and the 'non-tolerable' patient group had a significant higher pain score than the 'tolerable' group (p < 0.001). CONCLUSIONS: Our result shows that subjective pain severity during shock wave lithotripsy is high but may be well tolerated in some patients. Our findings raise the question as to whether routine analgesics are required during newer generation shock wave lithotripsy procedures in all patients with a urinary stone.

Analgesia↗

PubMed2004

Nocturia and complementary indices: determination and quantification of the cause of nocturia by frequency-volume charts in women with lower urinary tract symptoms.

We evaluated differences between women with lower urinary tract symptoms (LUTS) with and without nocturia in terms of voiding habits, urine production and voided volumes in order to determine and quantify the cause of nocturia by using frequency-volume (FV) charts. At the initial visit, all patients underwent a detailed clinical evaluation including an International Prostate Symptom Score assessment, received a thorough explanation from the study coordinators, and were requested to complete a 3-day FV chart. Of the 123 women enrolled, 106 (86.2%) 20-83 years old (median age 55.0) completed the study. Nocturnal urine volume was higher in nocturics than in non-nocturics, but this was not statistically significant. Total daytime voided volume was lower in nocturics than in non-nocturics ( P=0.030) but with no detectable difference in total voided volume. To identify possible risk factors, we examined age and night time parameters including the nocturnal bladder capacity index (NBCI), nocturnal polyuria index (NPI) and nocturia index (NI) by univariate logistic analysis. When nocturia was defined as voiding at least twice per night, age and NI were found to be associated with it by univariate analysis. These two variables were further analyzed using a multivariate logistic model to determine their association with nocturia. In the multivariate analysis, a positive association was observed between age and nocturia. Patients 50 years or older had a 3.9-fold higher risk [odds ratio (OR) 3.86; 95% confidence interval (CI) 1.60-9.31; P=0.003] of voiding at least twice per night than those younger than 50 years. In the same model, patients with NI greater than 1.5 had a 4.5-fold higher risk of voiding at least twice per night (OR 4.59; 95% CI 1.80-11.17; P=0.001). FV charts are valuable for determining the cause of nocturia in women with LUTS. Our findings suggest that age and the NI may be important variables in the evaluation of nocturia in women with LUTS.

Adult↗

PubMed2004

Voiding diary for the evaluation of urinary incontinence and lower urinary tract symptoms: prospective assessment of patient compliance and burden.

AIMS: Voiding diary duration may be related to patient compliance and burden. To test this hypothesis, we evaluated patient compliance and burden. METHODS: Between January and July 2002, we prospectively evaluated 162 patients (57 males and 105 females, mean age 53.0, range 20-81 years) with stress urinary incontinence or lower urinary tract symptoms. At the initial visit, all patients underwent a detailed clinical evaluation including an International Prostate Symptom Score (I-PSS) assessment and were randomly requested to complete 2-day, 3-day, or 7-day voiding diaries (the three study groups). At the second visit, a simple self-administered questionnaire was completed by all patients. The questionnaire included 11 items on subject demographics and voiding diary-keeping. RESULTS: No significant differences were found in either the accuracy of diary-keeping or the daily average number of omissions when the three groups were compared. However, as the diary duration increased, the mean burden scores increased (P = 0.005), and the mean preferred duration of the diary in the 7-day group was significantly higher than that of the 2-day or 3-day groups (P < 0.001). After categorizing patients into two groups according to the degree of patient burden, members of the group with a greater perceived burden were found to have a significantly higher I-PSS quality of life score (P = 0.045) and to have kept a diary for a longer time (P = 0.038). CONCLUSIONS: Our results suggest that keeping a diary for 7 days may increase patient burden and thus, we recommend that the 7-day diary should be reduced to cover fewer days.

Adult↗

PubMed2004

Association of bladder tumors and GA genotype of -308 nucleotide in tumor necrosis factor-alpha promoter with greater tumor necrosis factor-alpha expression.

OBJECTIVES: To investigate whether the genetic polymorphism of the -308 nucleotide in the tumor necrosis factor-alpha (TNF-alpha) promoter is associated with bladder cancer. METHODS: DNA samples from blood and tumor were analyzed by polymerase chain reaction-based restriction fragment length polymorphism to characterize the genetic polymorphism of the -308 nucleotide in the TNF-alpha promoter. TNF-alpha mRNA expression levels were assessed by quantitative competitive polymerase chain reaction, and the serum concentrations of TNF-alpha were measured using enzyme-linked immunosorbent assay. RESULTS: Patients with bladder tumor and control subjects did not differ in their genetic polymorphism of the -308 nucleotide (P = 0.259). However, the relation of the tumor grade with the GA phenotype was statistically significant (P = 0.04). TNF-alpha mRNA concentrations were also significantly greater in the GA genotype than in the GG genotype (P = 0.022). The TNF-alpha serum levels of the GA genotype were significantly greater than those of the GG genotype for both patients and controls. However, patients with bladder tumor had significantly greater TNF-alpha serum levels than did the controls for both the GG and the GA genotypes (GG type, P = 0.001; GA type, P = 0.009). CONCLUSIONS: The genotype of the -308 nucleotide in the TNF-alpha promoter had a statistically significant effect on TNF-alpha production and was related to the bladder tumor grade. The GA polymorphism might be associated with a statistically significant increase in gene transcription. That the TNF-alpha serum levels were greater in the patients with bladder tumor compared with controls suggests that high TNF-alpha production is associated with bladder tumor development and that bladder tumors may secrete TNF-alpha.

Genotype↗

PubMed2004

Novel algorithm for improving accuracy of ultrasound measurement of residual urine volume according to bladder shape.

OBJECTIVES: To suggest a novel algorithm based on individually determined proportionality constants to improve the accuracy of noninvasively calculated residual urine volume using ultrasound bladder images. METHODS: The residual urine volume of 116 subjects was calculated from ultrasound images obtained using a conventional two-dimensional ultrasound device at two institutions. The proposed method uses individually determined proportionality constants for specific bladder shapes. The corresponding true residual volumes were determined by measuring the catheterized volume. The accuracy of our method was confirmed by comparing the mean and standard deviation of the fractional absolute error (FAE) versus true volume with values obtained using other methods, which rely on fixed constants. RESULTS: The calculated residual bladder volume of 116 patients correlated significantly (r = 0.94, P <0.001) and the differences from the true values were not statistically significant (P = 0.42). The mean FAE was 0.17 +/- 0.10. Subgroups divided by sex, postvoid residual urine volume (over and under 150 mL), and institution produced different results (mean FAE for men 0.15 +/- 0.11 and for women 0.18 +/- 0.12; mean FAE for greater than 150 mL, 0.16 +/- 0.11 and for less than 150 mL, 0.17 +/- 0.14; mean FAE for Seoul National University Hospital 0.15 +/- 0.10 and for Seoul National University Bundang Hospital 0.18 +/- 0.18). Our method provided better accuracy than other known formulas using a conventional two-dimensional ultrasound scanner. The latter multiply the product of the sagittal height and depth and transverse width by a fixed coefficient. CONCLUSIONS: Our method, based on individually determined proportionality constants, improved the accuracy of residual bladder volume determinations. The proposed algorithm can easily be implemented on a personal computer connected to a conventional ultrasound imaging unit.

Adult↗

PubMed2003

Simple retrograde balloon dilation for treatment of ureteral strictures: etiology-based analysis.

This study consists of an analysis of the results of simple retrograde balloon dilation in the treatment of ureteral strictures for the evaluation of the long-term efficacy of this procedure, and the factors affecting its success rate. A prospective study was performed on 43 ureteral strictures (22 malignant, 21 benign) from 37 patients treated with retrograde balloon dilation from October 1997 to May 1999. After the stricture segments were dilated, ureteral stents were indwelled uniformly for 3 weeks. Strictures were postoperatively followed up radiographically at 1, 3, 6 and 12 months, and annually thereafter. Success was defined by symptomatic and radiographic improvement. The follow-up periods ranged from 8 to 57 months (mean 41 months). The success rates of the benign strictures at 12 and 36 months were much higher than those of the malignant strictures (67 and 57% vs., 18 and 14%, p=0.0009). While 56% and 47% of the patients with strictures shorter than 2 cm were successful at 12 and 36 months, respectively, none with strictures longer than 2 cm were successful at the same follow-up periods (p=0.0002). Of the successful benign cases with a shorter segment at 12 months, 12 out of 14 (86%) showed persistent long-term successes at the 36 months follow-up. Other prognostic factors, such as sex, age, location, disappearance of a waist, dilation time and grade of hydronephrosis, were not found to influence the success rate. A multivariate analysis revealed the etiology and stricture length were the only significant prognostic factors affecting the final outcome (p=0.030 and p=0.0262, respectively, by Cox's proportional hazards model). In consideration of its minimal invasiveness and acceptable long-term outcome, simple retrograde balloon dilation is an effective treatment modality for benign ureteral stricture with a short segment (< or = 2 cm), and a shorter duration of stenting (3-weeks) is viable.

Adult↗

PubMed2002

Laparoscopic nephrectomy for tuberculous nonfunctioning kidney: comparison with laparoscopic simple nephrectomy for other diseases.

OBJECTIVES: To summarize the results of our 31 consecutive laparoscopic nephrectomies for renal tuberculosis and compare them with 45 laparoscopic nephrectomies performed for other benign etiologies. We previously reported our initial successful experiences in expanding the role of laparoscopic surgery with the introduction of laparoscopic nephrectomy for renal tuberculosis. METHODS: Thirty-one laparoscopic nephrectomies for renal tuberculosis were performed between June 1996 and December 2001. The patients consisted of 11 men and 20 women with a mean age of 44.2 years (range 29 to 64). The control group consisted of 17 men and 28 women with a mean age of 48.6 years (range 17 to 60). The two groups were comparable with regard to demographic data. Statistical analyses were used to compare the two groups in terms of various parameters, including surgical time, blood loss, analgesic requirements, resumption of oral intake, and hospital stay. RESULTS: Laparoscopic nephrectomy was successful in 30 cases of the tuberculosis group and 44 cases of the control group. The two groups showed comparable perioperative and postoperative parameters, except for mean operative time, which, at 244 minutes for the tuberculosis group, was significantly greater than the 216 minutes for the control group (P <0.05). No significant intraoperative or postoperative complications were observed in either group. CONCLUSIONS: The results of this study indicate that laparoscopic nephrectomy for renal tuberculosis is a safe, effective, and less invasive treatment modality. Therefore, we suggest that the renal tuberculous nonfunctioning kidney should be approached initially using the laparoscopic approach.

Adult↗

PubMed2002

Laparoscopy for definite localization and simultaneous treatment of ectopic ureter draining a dysplastic kidney in children.

BACKGROUND AND PURPOSE: Single-system ectopic ureter draining a dysplastic kidney is a rare urologic abnormality. In this study, we evaluated our own experience using laparoscopy for the simultaneous identification and removal of such ureterorenal units. PATIENTS AND METHODS: Between February 1999 and August 2001, four girls with a mean age of 11 years presented with urinary incontinence. After imaging studies including CT scan, MRI, or both were done, all the patients underwent laparoscopy for definitive localization and simultaneous treatment. RESULTS: In all cases, ultrasonography and intravenous urography combined to reveal a single normal kidney. Even the CT scan could not identify the dysplastic kidney or ectopic ureter in three children. Laparoscopy was performed transperitoneally in all four patients, and a small dysplastic kidney was identified. Discovery of the kidney was not difficult because we initially identified the ureter crossing over the iliac vessels. Laparoscopic nephroureterectomy was successful in all patients with a mean operative time of 102 minutes. There was no significant intraoperative or postoperative complication, and the mean postoperative hospital stay was 2.5 days. All patients have remained completely dry without any problems after surgery. CONCLUSIONS: For patients having a clinical suspicion of ectopic ureter draining a dysplastic kidney, laparoscopy may represent an alternative modality for simultaneous diagnosis and treatment.

Adolescent↗