G. Barbalias - Academia.edu (original) (raw)

Papers by G. Barbalias

Research paper thumbnail of The laparoscopic management of a primary adrenal malignant melanoma

European Urology Supplements, 2005

Research paper thumbnail of In vivo estimation of radiation dose in renal pelvis and parenchyma during renography

Nuclear Medicine Communications, 1995

A method is presented for the determination of the spatio-temporal distribution of the radionucli... more A method is presented for the determination of the spatio-temporal distribution of the radionuclide in the kidney and estimation of the dose in the renal pelvis wall and parenchyma, during renograms, on the basis of real data. A protocol was formulated by means of which the processing of the frames acquired in the various stages of the renogram enables the determination of the mass of the renal pelvis and the parenchyma as well as the time distribution of radioactivity in these compartments. The proposed methodology was applied to 30 normal subjects and 35 patients with obstructive nephropathy, acute and chronic obstructive uropathy and hydronephrosis. Our results, when compared with the MIRD dose estimations for the entire kidney showed slight deviations in normals, whereas very significant deviations were observed in the cases with pathology. This is due to the fact that the mass of the 'source' and 'target' organs as well as the biodistribution of the radiopharmaceuticals are essential in dose determination and were completely different in our calculations from those used in the MIRD estimations. Comparing the absorbed dose in renal parenchyma and pelvis wall with that estimated in vivo for the kidney considered as a system of one compartment, we found large differences only in abnormal cases. Differences were also noted between the absorbed dose in the aforementioned renal compartments depending on the considered abnormal renal states.

Research paper thumbnail of Static urethral pressure profile (S.U.P.P.) or video-dynamic pressure profile (V.D.P.P.) in the evaluation of multiple sclerosis (M.S.)?

Journal of Neuroimmunology, 1995

Research paper thumbnail of Aspects concerning posterior urethral valves

International Urology and Nephrology, 1989

Twenty-six boys were evaluated and treated for posterior urethral vanes. At the time the valves w... more Twenty-six boys were evaluated and treated for posterior urethral vanes. At the time the valves were diagnosed unilateral or bilateral vesicoureteral reflux was present in 58 ~ of the ureters and 69 ~o of the children, while dilatation of the upper urinary tract was present in 88 ~o and 92 Yo, respectively. There was a variety of symptoms and signs, but the most prominent in neonates and infants were vesical urine retention, palpable kidneys and failure to thrive, whereas in the older children voiding dysfunction, incontinence and urinary infection were the most common. Twenty-four out of 26 boys were managed by primary valve ablation and in 62.5 ~ of them this type of treatment was adequate in resolving or sufficiently improving clinical manifestations and roentgenologic findings, requiring no further management. Urinary diversion in the form of vesicostomy and cutaneous ureterostomy was preserved for those patients who did not improve with vane ablation alone. The current aspects concerning posterior urethral valves are also discussed.

Research paper thumbnail of Intravesical bacillus Calmette-Guérin administration in the prophylaxis of superficial bladder cancer

International Urology and Nephrology, 1990

A total of 68 patients received prophylactic/adjuvant intravesical Pasteur strain bacillus Calmet... more A total of 68 patients received prophylactic/adjuvant intravesical Pasteur strain bacillus Calmette-Gu6rin (BCG) instillations following transurethral resection for superficial bladder carcinoma. An induction phase consisting of 6 weekly instillations was followed by a maintenance phase consisting of 1 instillation given every 3 months. A second 6-week course of BCG was administered to initial failure followed again by a quarterly maintenance therapy. The response rate for patients treated with one 6-week course was 56 ~, while complete response was achieved in 72% when both treatment courses were considered. Follow-up period lasted at least 2 years after each course of BCG. These results suggest that additional courses of BCG increase the prophylactic efficacy of intracavitary BCG. Regarding the purified protein derivative (PPD) skin test and granulomatous response in the bladder, it has been shown in the present study that, although favourable results occurred more frequently among patients with either PPD conversion from negative to positive or vesical granuloma formation, neither of these indices should be considered reliable prognostic indicators.

Research paper thumbnail of Prognostic factors for the operative correction of stress urinary incontinence

International Urology and Nephrology, 1995

Investigating the reliability of using some clinical and laboratory parameters as long-term progn... more Investigating the reliability of using some clinical and laboratory parameters as long-term prognostic factors in properly selected patients for stress urinary surgery could help in the prediction of the long-term result in each case.

Research paper thumbnail of A comparative, crossover study of the efficacy and safety of sildenafil and apomorphine in men with evidence of arteriogenic erectile dysfunction

International Journal of Impotence Research, 2004

The aim of the study was to establish and compare the efficacy and safety of sildenafil and apomo... more The aim of the study was to establish and compare the efficacy and safety of sildenafil and apomorphine in men with arteriogenic erectile dysfunction (ED). In all, 43 men with ED and postinjection max penile systolic velocity o25 cm/s in repeated Doppler ultrasonography were included. Of these, 24 men started on apomorphine 2 mg and 19 on sildenafil 50 mg, the doses titrated up to 3 and 100 mg according to effectiveness and tolerability. Safety was evaluated according to adverse events (AEs) and patient withdrawal. Efficacy was the percentage of attempts resulting in erections firm enough for intercourse, based on event log data. The incidence of AEs with apomorphine 3 mg was higher than with sildenafil 100 mg. Two men on apomorphine 3 mg discontinued treatment due to AEs. The overall success rate of sildenafil was 63.7% compared to 32.1% of apomorphine (Pearson v 2 , Po0.01). Of all men, 25 (58.1%) responded to sildenafil 50 mg without the need for dose increase, while only one responded to apomorphine 2 mg. The response to sildenafil 50 mg was age related (analysis of variance, p¼0.04). Satisfaction was reported by 76.75 and 13.95% of patients for sildenafil and apomorphine, respectively, but 20.9% were not satisfied with any of the two drugs. In conclusion, this study provides clear evidence that sildenafil, even at 50 mg dose, is more effective than apomorphine 3 mg in men with arteriogenic ED. The fact that one out of five patients is not satisfied with the above-studied drugs shows that new oral agents need to be evaluated for the treatment of this disorder.

Research paper thumbnail of Erectile dysfunction in men with obstructive sleep apnea syndrome: a randomized study of the efficacy of sildenafil and continuous positive airway pressure

International Journal of Impotence Research, 2004

The aim of this study was to compare the efficacy of sildenafil and continuous positive airway pr... more The aim of this study was to compare the efficacy of sildenafil and continuous positive airway pressure (CPAP) in men with erectile dysfunction (ED) and obstructive sleep apnea syndrome (OSAS). In all, 30 men were randomly treated for 12 weeks either with sildenafil 100 mg before intercourse (15 men) or CPAP during night time sleep (15 men). Under sildenafil, 97/180 (53.9%) of attempted intercourses were successful compared to 33/138 (23.9%) under CPAP. The mean IIEF (erectile function domain score) was 12.9 and 9.3 after sildenafil and CPAP treatment, respectively (P=0.007), compared to 7.9 and 7 at baseline. In all, 53.3% of patients were satisfied with sildenafil and 20% with CPAP for ED treatment (P=0.058). Although sildenafil was superior to CPAP, comorbidities and OSAS per se possibly resulted in a lower effectiveness of sildenafil compared to that in the general population of ED men. While about half of the patients were not satisfied even with the more effective treatment, we conclude that a combination of the two therapeutic tools or a different therapeutic mode should be studied further.

Research paper thumbnail of Serious Complications of Tuberculous Epididymitis

Infection, 2000

Tuberculous epididymitis is a rare entity associated with minor complications. We present two cas... more Tuberculous epididymitis is a rare entity associated with minor complications. We present two cases of tuberculous epididymitis associated with serious complications (bilateral psoas abscesses and Addison's disease with psoas abscess). A review of the literature disclosed six additional cases associated with serious complications (Addison's disease, inappropriate antidiuretic hormone secretion, central nervous system involvement) which are discussed and compared to these cases. We conclude that tuberculous epididymitis represents a grave sequela of genital tract involvement and may be associated with serious and even fatal complications.

Research paper thumbnail of Comparison of the Efficacy of Tolterodine and Oxybutynin in Different Urodynamic Severity Grades of Idiopathic Detrusor Overactivity

European Urology, 2004

Objective: To compare the efficacy of tolterodine and oxybutynin in the treatment of specific, ac... more Objective: To compare the efficacy of tolterodine and oxybutynin in the treatment of specific, according to their urodynamic grade of severity, populations with overactive detrusor. Methods: In this open, randomized, two-way crossover study 128 women with urodynamically confirmed, idiopathic detrusor overactivity were recruited. Patients were categorized in 4 grades of severity groups, according to the characteristics of the first overactive detrusor contraction during filling cystometrogram: high volume-low pressure (grade-group I), high volume-high pressure (grade-group II), low volume-low pressure (grade-group III) and low volume-high pressure (grade-group IV). The primary outcome measure was average volume of voided urine per micturition. Results: 107 patients successfully completed the study protocol and were included in the analyses: 40 in group IV, 36 in III, 25 in II and 6 in group I. In groups IV and III both oxybutynin and tolterodine significantly increased the average volume of voided urine per micturition but the differences between the drugs were not significant (p > 0.05). In group II neither of the drugs achieved significant changes in the outcome measure (p > 0.05). Conclusions: Tolterodine and oxybutynin are clinically equipotent in treating detrusor overactivity in specific severity groups of patients, although urodynamic effects are somewhat different. #

Research paper thumbnail of Gabapentin in the management of the recurrent, refractory, idiopathic priapism

International Journal of Impotence Research, 2004

Recurrent idiopathic priapism is a difficult problem to treat and a true emergency for the physic... more Recurrent idiopathic priapism is a difficult problem to treat and a true emergency for the physicians, and often even invasive therapeutic interventions fail. We recently managed three men with refractory idiopathic priapism with oral gabapentin. They responded to treatment within 48 h. Two men continue not to experience prolonged erections while treated with lower doses of gabapentin for 16 and 24 months, respectively. The third, after a successful treatment for 6 months, stopped gabapentin and priapism recurred. He responded to treatment again and continues to be free of episodes for 9 months. Gabapentin may be a safe alternative for the management of refractory idiopathic priapism.

Research paper thumbnail of The laparoscopic management of a primary adrenal malignant melanoma

European Urology Supplements, 2005

Research paper thumbnail of In vivo estimation of radiation dose in renal pelvis and parenchyma during renography

Nuclear Medicine Communications, 1995

A method is presented for the determination of the spatio-temporal distribution of the radionucli... more A method is presented for the determination of the spatio-temporal distribution of the radionuclide in the kidney and estimation of the dose in the renal pelvis wall and parenchyma, during renograms, on the basis of real data. A protocol was formulated by means of which the processing of the frames acquired in the various stages of the renogram enables the determination of the mass of the renal pelvis and the parenchyma as well as the time distribution of radioactivity in these compartments. The proposed methodology was applied to 30 normal subjects and 35 patients with obstructive nephropathy, acute and chronic obstructive uropathy and hydronephrosis. Our results, when compared with the MIRD dose estimations for the entire kidney showed slight deviations in normals, whereas very significant deviations were observed in the cases with pathology. This is due to the fact that the mass of the 'source' and 'target' organs as well as the biodistribution of the radiopharmaceuticals are essential in dose determination and were completely different in our calculations from those used in the MIRD estimations. Comparing the absorbed dose in renal parenchyma and pelvis wall with that estimated in vivo for the kidney considered as a system of one compartment, we found large differences only in abnormal cases. Differences were also noted between the absorbed dose in the aforementioned renal compartments depending on the considered abnormal renal states.

Research paper thumbnail of Static urethral pressure profile (S.U.P.P.) or video-dynamic pressure profile (V.D.P.P.) in the evaluation of multiple sclerosis (M.S.)?

Journal of Neuroimmunology, 1995

Research paper thumbnail of Aspects concerning posterior urethral valves

International Urology and Nephrology, 1989

Twenty-six boys were evaluated and treated for posterior urethral vanes. At the time the valves w... more Twenty-six boys were evaluated and treated for posterior urethral vanes. At the time the valves were diagnosed unilateral or bilateral vesicoureteral reflux was present in 58 ~ of the ureters and 69 ~o of the children, while dilatation of the upper urinary tract was present in 88 ~o and 92 Yo, respectively. There was a variety of symptoms and signs, but the most prominent in neonates and infants were vesical urine retention, palpable kidneys and failure to thrive, whereas in the older children voiding dysfunction, incontinence and urinary infection were the most common. Twenty-four out of 26 boys were managed by primary valve ablation and in 62.5 ~ of them this type of treatment was adequate in resolving or sufficiently improving clinical manifestations and roentgenologic findings, requiring no further management. Urinary diversion in the form of vesicostomy and cutaneous ureterostomy was preserved for those patients who did not improve with vane ablation alone. The current aspects concerning posterior urethral valves are also discussed.

Research paper thumbnail of Intravesical bacillus Calmette-Guérin administration in the prophylaxis of superficial bladder cancer

International Urology and Nephrology, 1990

A total of 68 patients received prophylactic/adjuvant intravesical Pasteur strain bacillus Calmet... more A total of 68 patients received prophylactic/adjuvant intravesical Pasteur strain bacillus Calmette-Gu6rin (BCG) instillations following transurethral resection for superficial bladder carcinoma. An induction phase consisting of 6 weekly instillations was followed by a maintenance phase consisting of 1 instillation given every 3 months. A second 6-week course of BCG was administered to initial failure followed again by a quarterly maintenance therapy. The response rate for patients treated with one 6-week course was 56 ~, while complete response was achieved in 72% when both treatment courses were considered. Follow-up period lasted at least 2 years after each course of BCG. These results suggest that additional courses of BCG increase the prophylactic efficacy of intracavitary BCG. Regarding the purified protein derivative (PPD) skin test and granulomatous response in the bladder, it has been shown in the present study that, although favourable results occurred more frequently among patients with either PPD conversion from negative to positive or vesical granuloma formation, neither of these indices should be considered reliable prognostic indicators.

Research paper thumbnail of Prognostic factors for the operative correction of stress urinary incontinence

International Urology and Nephrology, 1995

Investigating the reliability of using some clinical and laboratory parameters as long-term progn... more Investigating the reliability of using some clinical and laboratory parameters as long-term prognostic factors in properly selected patients for stress urinary surgery could help in the prediction of the long-term result in each case.

Research paper thumbnail of A comparative, crossover study of the efficacy and safety of sildenafil and apomorphine in men with evidence of arteriogenic erectile dysfunction

International Journal of Impotence Research, 2004

The aim of the study was to establish and compare the efficacy and safety of sildenafil and apomo... more The aim of the study was to establish and compare the efficacy and safety of sildenafil and apomorphine in men with arteriogenic erectile dysfunction (ED). In all, 43 men with ED and postinjection max penile systolic velocity o25 cm/s in repeated Doppler ultrasonography were included. Of these, 24 men started on apomorphine 2 mg and 19 on sildenafil 50 mg, the doses titrated up to 3 and 100 mg according to effectiveness and tolerability. Safety was evaluated according to adverse events (AEs) and patient withdrawal. Efficacy was the percentage of attempts resulting in erections firm enough for intercourse, based on event log data. The incidence of AEs with apomorphine 3 mg was higher than with sildenafil 100 mg. Two men on apomorphine 3 mg discontinued treatment due to AEs. The overall success rate of sildenafil was 63.7% compared to 32.1% of apomorphine (Pearson v 2 , Po0.01). Of all men, 25 (58.1%) responded to sildenafil 50 mg without the need for dose increase, while only one responded to apomorphine 2 mg. The response to sildenafil 50 mg was age related (analysis of variance, p¼0.04). Satisfaction was reported by 76.75 and 13.95% of patients for sildenafil and apomorphine, respectively, but 20.9% were not satisfied with any of the two drugs. In conclusion, this study provides clear evidence that sildenafil, even at 50 mg dose, is more effective than apomorphine 3 mg in men with arteriogenic ED. The fact that one out of five patients is not satisfied with the above-studied drugs shows that new oral agents need to be evaluated for the treatment of this disorder.

Research paper thumbnail of Erectile dysfunction in men with obstructive sleep apnea syndrome: a randomized study of the efficacy of sildenafil and continuous positive airway pressure

International Journal of Impotence Research, 2004

The aim of this study was to compare the efficacy of sildenafil and continuous positive airway pr... more The aim of this study was to compare the efficacy of sildenafil and continuous positive airway pressure (CPAP) in men with erectile dysfunction (ED) and obstructive sleep apnea syndrome (OSAS). In all, 30 men were randomly treated for 12 weeks either with sildenafil 100 mg before intercourse (15 men) or CPAP during night time sleep (15 men). Under sildenafil, 97/180 (53.9%) of attempted intercourses were successful compared to 33/138 (23.9%) under CPAP. The mean IIEF (erectile function domain score) was 12.9 and 9.3 after sildenafil and CPAP treatment, respectively (P=0.007), compared to 7.9 and 7 at baseline. In all, 53.3% of patients were satisfied with sildenafil and 20% with CPAP for ED treatment (P=0.058). Although sildenafil was superior to CPAP, comorbidities and OSAS per se possibly resulted in a lower effectiveness of sildenafil compared to that in the general population of ED men. While about half of the patients were not satisfied even with the more effective treatment, we conclude that a combination of the two therapeutic tools or a different therapeutic mode should be studied further.

Research paper thumbnail of Serious Complications of Tuberculous Epididymitis

Infection, 2000

Tuberculous epididymitis is a rare entity associated with minor complications. We present two cas... more Tuberculous epididymitis is a rare entity associated with minor complications. We present two cases of tuberculous epididymitis associated with serious complications (bilateral psoas abscesses and Addison's disease with psoas abscess). A review of the literature disclosed six additional cases associated with serious complications (Addison's disease, inappropriate antidiuretic hormone secretion, central nervous system involvement) which are discussed and compared to these cases. We conclude that tuberculous epididymitis represents a grave sequela of genital tract involvement and may be associated with serious and even fatal complications.

Research paper thumbnail of Comparison of the Efficacy of Tolterodine and Oxybutynin in Different Urodynamic Severity Grades of Idiopathic Detrusor Overactivity

European Urology, 2004

Objective: To compare the efficacy of tolterodine and oxybutynin in the treatment of specific, ac... more Objective: To compare the efficacy of tolterodine and oxybutynin in the treatment of specific, according to their urodynamic grade of severity, populations with overactive detrusor. Methods: In this open, randomized, two-way crossover study 128 women with urodynamically confirmed, idiopathic detrusor overactivity were recruited. Patients were categorized in 4 grades of severity groups, according to the characteristics of the first overactive detrusor contraction during filling cystometrogram: high volume-low pressure (grade-group I), high volume-high pressure (grade-group II), low volume-low pressure (grade-group III) and low volume-high pressure (grade-group IV). The primary outcome measure was average volume of voided urine per micturition. Results: 107 patients successfully completed the study protocol and were included in the analyses: 40 in group IV, 36 in III, 25 in II and 6 in group I. In groups IV and III both oxybutynin and tolterodine significantly increased the average volume of voided urine per micturition but the differences between the drugs were not significant (p > 0.05). In group II neither of the drugs achieved significant changes in the outcome measure (p > 0.05). Conclusions: Tolterodine and oxybutynin are clinically equipotent in treating detrusor overactivity in specific severity groups of patients, although urodynamic effects are somewhat different. #

Research paper thumbnail of Gabapentin in the management of the recurrent, refractory, idiopathic priapism

International Journal of Impotence Research, 2004

Recurrent idiopathic priapism is a difficult problem to treat and a true emergency for the physic... more Recurrent idiopathic priapism is a difficult problem to treat and a true emergency for the physicians, and often even invasive therapeutic interventions fail. We recently managed three men with refractory idiopathic priapism with oral gabapentin. They responded to treatment within 48 h. Two men continue not to experience prolonged erections while treated with lower doses of gabapentin for 16 and 24 months, respectively. The third, after a successful treatment for 6 months, stopped gabapentin and priapism recurred. He responded to treatment again and continues to be free of episodes for 9 months. Gabapentin may be a safe alternative for the management of refractory idiopathic priapism.