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Rainer Hofmann

Publications and source records attributed to Rainer Hofmann.

At least 19 recordsLinked to original sources
PubMed2006

Biochemical markers of bone turnover in patients with localized and metastasized prostate cancer.

OBJECTIVE: To evaluate and compare the value of several markers of bone turnover in different stages of prostate cancer, as bone metastases are a common feature in this disease, and for assessing bone metastases both bone formation and bone resorption markers are diagnostic. PATIENTS AND METHODS: The prospective study included 219 men, i.e. 129 undergoing radical retropubic prostatectomy (RRP) and 25 with bone metastases due to prostate cancer, and 65 with benign urological disorders who served as controls. Before any treatment the concentrations of alkaline phosphatase (ALP), osteocalcin, serum C-terminal telopeptide of type I collagen (S-CTX) and tartrate-resistant acid phosphatase type 5b (TRACP5b) were determined. RESULTS: Men undergoing RRP were divided into those with lymph node-negative, localized (pT3, 101) and lymph node-positive (28) disease, after histological examination. The controls had the lowest marker levels while patients with bone metastases due to prostate cancer had the highest levels, with significance for ALP, osteocalcin and TRACP5b. Patients with lymph node-positive cancer had significantly high serum levels of TRACP5b and ALP but not for osteocalcin and S-CTX. CONCLUSIONS: Bone turnover markers represent a new diagnostic tool in prostate cancer; the present data show that both bone resorption and bone formation are crucial for detecting bone metastases in prostate cancer. The value of bone turnover markers in high-risk patients should be evaluated in a longitudinal study.

Adult↗
PubMed2006

Complications of transurethral resection of the prostate (TURP)--incidence, management, and prevention.

OBJECTIVES: To update the complications of transurethral resection of the prostate (TURP), including management and prevention based on technological evolution. METHODS: Based on a MEDLINE search from 1989 to 2005, the 2003 results of quality management of Baden-Württemberg, and long-term personal experience at three German centers, the incidence of complications after TURP was analyzed for three subsequent periods: early (1979-1994); intermediate (1994-1999); and recent (2000-2005) with recommendations for management and prevention. RESULTS: Technological improvements such as microprocessor-controlled units, better armamentarium such as video TUR, and training helped to reduce perioperative complications (recent vs. early) such as transfusion rate (0.4% vs. 7.1%), TUR syndrome (0.0% vs. 1.1%), clot retention (2% vs. 5%), and urinary tract infection (1.7% vs. 8.2%). Urinary retention (3% vs. 9%) is generally attributed to primary detrusor failure rather than to incomplete resection. Early urge incontinence occurs in up to 30-40% of patients; however, late iatrogenic stress incontinence is rare (<0.5%). Despite an increasing age (55% of patients are older than 70), the associated morbidity of TURP maintained at a low level (<1%) with a mortality rate of 0-0.25%. The major late complications are urethral strictures (2.2-9.8%) and bladder neck contractures (0.3-9.2%). The retreatment rate range is 3-14.5% after five years. CONCLUSIONS: TURP still represents the gold standard for managing benign prostatic hyperplasia with decreasing complication rates. Technological alternatives such as bipolar and laser treatments may further minimize the risks of this technically difficult procedure.

Humans↗
PubMed2006

Impact of evidence-based interdisciplinary guidelines on testis cancer management.

BACKGROUND: In 1999, interdisciplinary evidence-based guidelines were elaborated for treatment of germ cell tumors in Germany. The aims of the current study were to analyze failures in diagnosis and therapy and to demonstrate the influence of guidelines on individual therapeutic approaches and clinical outcome. Therefore, patient collectives treated before the introduction of guidelines (Group A, 1990-1999, n = 234) and those thereafter (Group B, 2000-2002, n = 84) were compared for recurrence and survival. METHODS: In both groups, medical and/or surgical treatment and clinical outcome were evaluated for therapeutic mistakes and violations of guidelines. These were analyzed for their clinical consequences. RESULTS: There was no significant difference between groups concerning median age of patients or clinical stage before therapy. Altogether, 27.8% and 8.3% of all patients in Group A and B, respectively, displayed therapeutic mistakes (P < 0.005); 63% of these patients in Group A and 100% of these patients in Group B received an overtreatment. In Group A, 19/234 (8.1%) patients relapsed and 53% of these patients had been treated insufficiently (P < 0.005). Advanced disease caused the death of 3/234 patients in this study. As of this writing, only 3 of 84 (3.6%) patients in Group B have relapsed, and no patient has died because of tumor or consecutive treatment. CONCLUSIONS: The integration of interdisciplinary evidence-based guidelines for treatment of testicular germ cell tumors has led to significant reduction of both overtreatment and treatment failure and/or relapse that were due to inappropriate primary therapy. Evidence-based guidelines should serve as internal quality controls in all institutions treating patients with testicular germ cell tumors.

Adolescent↗
PubMed2006

Analysis of the mRNA expression of the TGF-Beta family in testicular cells and localization of the splice variant TGF-beta2B in testis.

The transforming growth factors (TGF)-beta, TGF-beta1, TGF-beta2, and TGF-beta3, and their receptors [TbetaRI, TbetaRII, TbetaRIII (betaglycan)] elicit many functions in the testis, for example, they perturb the blood testis barrier (BTB). Although expression of the ligands and receptors have been investigated, the alternative splice variants are incompletely examined. We therefore have analyzed all ligands, the receptors, and the splice variants TbetaRIB, TbetaRIIB, and TGF-beta2B in testicular cells from rat and mouse. In mouse, the novel transcript variant TGF-beta2B was identified and was found in Leydig cells, spermatogonia, pachytene spermatocytes, and in the apical regions of the Sertoli cells in adult testis. Even though expression of the splice variant TbetaRIB could be shown in mouse and rat, we never found the isoform TbetaRIIB in the rat cell lines studied. Whereas in all testicular cells expression of all TGF-beta ligands could be shown, receptor mRNA expression was slightly more diverse. Furthermore, expression pattern of the splice variants was more heterogeneous, for example, TbetaRIB was not detectable in adult Sertoli cells, primary peritubular cells, and immortalized peritubular cells. The heterogeneous expression of the receptors and especially of the splice variants might provide possible clues for the different functions of the TGF-beta ligands in testicular cells.

Alternative Splicing↗
PubMed2006

Clinical significance of a prostate-specific antigen flare phenomenon in patients with hormone-refractory prostate cancer receiving docetaxel.

Docetaxel has shown promise for the treatment of hormone-refractory prostate cancer and has become the standard of care. The flare phenomenon is a known entity in androgen-deprivation therapy of advanced prostate cancer and it has also been described in palliative chemotherapy of hormone-refractory prostate cancer. The aim of this study was to evaluate the clinical impact of a prostate-specific antigen flare phenomenon in docetaxel-treated hormone-refractory prostate cancer patients. From December 2002 to August 2005, we treated 44 patients with hormone-refractory prostate cancer applying docetaxel-based regimens. Prostate-specific antigen levels were determined before therapy and weekly thereafter. Patients were divided into three groups: response (group 1), progression (group 2) and flare (group 3). Flare was defined as initially rising prostate-specific antigen under therapy, dropping thereafter to values below baseline. The groups were compared for overall survival by Kaplan-Meier analysis. We observed a prostate-specific antigen flare phenomenon in eight (18%) of 44 evaluable patients; 24 (54.5%) patients were primary responders and 12 (27.3%) experienced progressive disease. In group 3, prostate-specific antigen levels rose to 107-180% from baseline and then dropped to 21-68%. Kaplan-Meier analysis showed significantly better overall median survival for groups 1 (18 months, P=0.0005) and 3 (19 months, P=0.006) than for group 2 (7 months). Survival in groups 1 and 3 was comparable. Grade 3 and 4 toxicity was below 5% and equally distributed between the 3 groups. In our limited patient cohort, prostate-specific antigen flare phenomenon does not seem to be a clinically relevant issue in terms of overall survival. Thus, an initial rise of prostate-specific antigen under docetaxel therapy in hormone-refractory prostate cancer does not indicate therapeutic failure and should not lead to early withdrawal from therapy in the absence of clinical signs of progression.

Androgens↗
PubMed2006

Laparoscopic peritoneal drainage of symptomatic lymphoceles after pelvic lymph node dissection using methylene blue instillation.

BACKGROUND: Lymphoceles are frequent complications of pelvic lymph node dissection. While small lymphoceles often remain undetected, larger ones can cause complications and require further treatment, e.g. percutaneous tube drainage alone or in combination with sclerotherapy. However, recurrence rates are considerable, and long-lasting drainage may lead to infection, prolonged hospitalization, and as a consequence, increased overall costs. We report the results of a simplified laparoscopic approach to drain lymphoceles after radical prostatectomy plus pelvic lymphadenectomy using methylene blue instillation. METHODS: 13 patients with large symptomatic pelvic/retroperitoneal lymphoceles refractory to percutaneous tube drainage and doxycycline sclerotherapy received a laparoscopic transperitoneal marsupialization following instillation of a sterile diluted methylene blue solution into the drained cavity to refill and mark the lymphocele. RESULTS: All lymphoceles were sterile and ranged in size from 7 x 6 x 4 to 15 x 12 x 6 cm. Clinical symptoms included lower abdominal swelling, tenderness in the iliac fossa, ipsilateral lymphedema, deep venous thrombosis, wound fistula, and hydronephrosis due to ureteral obstruction. After methylene blue instillation, the lymphoceles were easily identified and opened. Median total operative time was 50 (range 25-70) min; blood loss was negligible. There was one complication in the form of a metachronous infection in the operating field and no relapses. Patients were discharged 1-5 (median 3) days after the surgical procedure. CONCLUSIONS: Laparoscopic peritoneal drainage requires greater operative skill than percutaneous approaches. However, the instillation of a methylene blue solution simplifies this procedure as the extent and location of the lymphoceles can be precisely identified during laparoscopy. We recommend early application of laparoscopic peritoneal drainage following methylene blue instillation for patients with sterile lymphoceles after pelvic lymph node dissection in whom temporary percutaneous drainage and sclerotherapy failed to resolve the lymph fluid collection.

Drainage↗
PubMed2005

Cellular retinoic acid binding protein I: expression and functional influence in renal cell carcinoma.

Despite the known anti-proliferative and tumor-suppressive effects seen with retinoic acid (RA), treatment of metastatic renal cell carcinoma (RCC) failed to meet the initial expectations. As the exact mechanisms of action of RA and especially the role of the cellular RA binding proteins (CRABP) have not been elucidated yet, we investigated the expression of CRABP-I and its potential influence on RA response in RCC. Real-time RT-PCR analysis disclosed a significant lack of CRABP-I expression in four RCC cell lines and 12 primary RCC samples; in contrast, high expression levels were found in the respective adjacent normal kidney tissue. To further investigate the impact of CRABP-I on RA response in RCC, A-498 RCC cells were employed as a cellular model system. CRABP-I was stably transfected into A-498 cells which consequently displayed substantial resistance to all-trans (ATRA) and 9-cis RA compared to vector controls lacking CRABP-I. Comparison of gene expression profiles of ATRA-treated CRABP-I-expressing A-498 cells and vector controls revealed specific regulation of 54 of approximately 20,000 genes tested on a selected human CodeLink UniSet Bioarray, with a prominent modulation of genes involved in transcriptional control, signaling, apoptosis, cell cycle regulation and metabolism. The genetic changes reported here contribute to a better understanding of the role of RA in RCC. They also provide new insights into CRABP-I-mediated signaling and gene expression.

Aged↗
PubMed2005

Application of thalidomide/interleukin-2 in immunochemotherapy-refractory metastatic renal cell carcinoma.

Thalidomide has been reported to yield anti-tumor activity in advanced renal cell carcinoma (RCC). We evaluated safety and efficacy of a combination therapy comprising interleukin (IL)-2 and thalidomide in patients with metastatic RCC refractory to both immuno- and chemotherapy. Twelve patients with progressive metastatic RCC who had failed prior treatment with immunochemotherapy and desired further active therapy were enrolled in this study. Oral thalidomide was started at 200 mg/day and escalated after 2 days to 400 mg/day at week 0. IL-2 at 7 MIU/m was given by s.c. injection, starting at week 1, days 1-5, weeks 1-4, with rest from IL-2 at weeks 5 and 6. Response was assessed every two therapy cycles. Ten patients were evaluable for response. There was no objective response; four patients showed stable disease for 14+, 11+, 10+ and 9 months, respectively. Toxicities were predominantly grade I-II, and included somnolence and constipation, as well as flu-like symptoms associated with IL-2. However, one patient developed serious constipation which led to a paralytic ileus and discontinuation of treatment. Another patient left the study after 7 weeks due to increasing disorientation/confusion. Eight patients required IL-2 dose reduction. Time on therapy ranged from 3 to 44 weeks (median 20 weeks). Median overall survival was 12+ months. At present, all patients have discontinued treatment. We conclude that outpatient administration of thalidomide/IL-2 is feasible in patients with heavily pretreated and progressive RCC who desire further active treatment. However, toxicity and costs are considerable, and clinical benefit is uncertain. Therefore, thalidomide/IL-2 might not represent a promising therapeutic approach for this subgroup of patients.

Adult↗
PubMed2005

Expression and functional influence of cellular retinoic acid-binding protein II in renal cell carcinoma.

INTRODUCTION: Retinoic acid (RA) and its derivates possess antiproliferative and tumor-suppressive abilities and are successfully used in the treatment of various malignancies. However, in metastatic renal cell carcinoma (RCC), its application did not meet first expectations. As the exact mechanisms of RA action and especially the role of the cellular retinoic acid-binding proteins (CRABP) still remain unclear, we studied the expression of CRABP-II and its potential influence on RA response in RCC. MATERIALS AND METHODS: We used the real-time RT-PCR methodology to investigate CRABP-II expression in 12 RCC samples and corresponding normal kidney tissue. Moreover, CRABP-II was cloned and overexpressed in CAKI-2 RCC cells. CRABP-II (un)transfected CAKI-2 cells were stimulated with all-trans RA (ATRA) and 9-cis RA, and their antiproliferative effects were evaluated using 3H-thymidine-proliferation assays. RESULTS: Using RPS9 and RPLP0 to normalize its expression, the median tumor/kidney ratio for CRABP-II expression was 0.16 and 0.12, respectively. Using proliferation assays, CRABP-II overexpressing CAKI-2 cells did not exhibit a significant change in RA sensitivity, but appeared to be less sensitive toward RA-stimulation compared to CAKI-2 cells expressing naturally low levels of CRABP-II (maximum difference, 59% at 3 microM ATRA). CONCLUSIONS: We were able to demonstrate a downregulation of CRABP-II expression in primary RCC tumor samples compared to the corresponding normal kidney tissue. However, CRABP-II overexpression in CAKI-2 RCC cells did not significantly influence RA associated antiproliferative actions. Further experiments are necessary to define the exact role of CRABP-II and its downregulation in RCC including its influence and dependence on other molecules involved in RA signalling and metabolism.

Aged↗
PubMed2004

Genetic pathways and new progression markers for prostate cancer suggested by microsatellite allelotyping.

PURPOSE: At diagnosis, the biological behavior of prostate cancer is uncertain, making the choice of an adequate therapy option difficult. Performing microsatellite allelotyping on a large series of consecutive prostate cancers procured during radical prostatectomy at our institution, we sought to identify molecular markers associated with disease progression. EXPERIMENTAL DESIGN: A total of 156 consecutive fresh tumor samples was prospectively collected and macroscopically dissected from the whole prostatectomy specimen immediately after operation. Histologically 100 samples contained >75% tumor cells and were therefore enrolled in the microsatellite allelotyping, using a total of 24 polymorphic markers for the chromosomal regions 5p, 5q, 7q, 8p, 9p, 9q, 13q, 17p, 17q, and 18q. Fresh paired normal and tumor DNA was investigated in fluorescent microsatellite analysis with automated laser product detection. RESULTS: The incidence of tumor-DNA alterations [loss of heterozygosity or allelic imbalance (AI)] was highest for chromosomal regions 13q and 8p with 72 and 71%, respectively, followed by chromosomes 7q, 18q, 5q, and 17p with 57, 53, 41, and 39%, respectively. Alterations at chromosomes 8p, 9p, 13q, and 17p were significantly (P < 0.05) associated with advanced tumor stage, whereas AI at 8p and 17p was also associated with high Gleason score (P < 0.05). AI at 5q and 9p was associated with regional lymph node metastasis (P < 0.05). The combination of AI at 8p and 13q was strongly associated with advanced tumor stage (P < 0.0001). CONCLUSIONS: With the obtained results, we are able to postulate three distinct pathways in prostate carcinogenesis, and we identified microsatellite markers of prognostic value.

Alleles↗
PubMed2004

Molecular serological detection of DNA alterations in transitional cell carcinoma is highly sensitive and stage independent.

PURPOSE: To evaluate the efficacy of fluorescent microsatellite analysis (MSA) for the serological diagnosis of transitional cell carcinoma (TCC) of the urinary tract analyzing free tumor DNA in the serum of cancer patients. EXPERIMENTAL DESIGN: We applied fluorescent MSA to detect serum-DNA alterations in patients suffering from bladder and upper urinary tract TCC and prospectively collected fresh tumor, peripheral blood, and serum specimens from 61 consecutive patients to obtain the corresponding DNA. Fluorescent MSA was performed with a total of 17 polymorphic markers from the chromosomal regions 5q, 8p, 9p, 9q, 13q, 14q, 17p, 17q, and 20q in the 61 cancer patients, as well as in 20 healthy controls. RESULTS: Molecular serological analysis led to tumor-specific diagnosis of TCC in 80.3% (49 of 61) of cases. Four healthy controls displayed serum-DNA artifacts rendering a specificity of 80%. The highest frequency of serum-DNA alterations was detected for chromosomal region 8p with 36%. Chromosomes 5q, 9p, and 20q showed serum-DNA alterations in 18 to 21%. The identification of serum-DNA alterations was not statistically associated with underlying local tumor stage (P = 0.29) but was more frequent in high-grade tumors (P = 0.08). CONCLUSIONS: MSA offers a highly sensitive method for serological diagnosis of TCC. To optimize specificity, simultaneous analysis of tumor DNA is advised to rule out artifacts resembling allelic imbalance in MSA of serum DNA.

Biomarkers, Tumor↗
PubMed2004

Genetic pathways and new progression markers for prostate cancer defined by microsatellite allelotyping.

A prospective study was carried out on a large cohort of males undergoing radical retropubic prostatectomy in order to identify genetic marker regions significantly associated with tumor formation. By comprehensive allotyping of chromosomes known to be associated with prostate carcinogenesis, an algorithm could be formulated for the genetic pathway and a method of discrimination between aggressive and less aggressive forms could be identified.

Alleles↗
PubMed2004

Application of retinoids in the treatment of renal cell carcinoma--a futile effort?

The therapeutic benefit of adding retinoids such as all-trans retinoic acid (RA), 9-cis-RA or 13-cis-RA to established single-agent or combination immuno/chemotherapy regimens for the treatment of metastatic renal cell carcinoma (RCC) has been extensively investigated during the last decade. However, at present results are contradictory and their application controversial. Moreover, recent studies indicated a significantly higher incidence of toxic side-effects in patients treated with retinoids in addition to established bio/chemotherapy. This Commentary summarizes preclinical and clinical trials investigating efficacy and toxicity of retinoids in the treatment of RCC.

Animals↗
PubMed2004

Fetoscopic placement of a transurethral stent for intrauterine obstructive uropathy.

PURPOSE: Fetal urinary obstructive uropathy and consecutive oligohydramnios result in a poor outcome. Usually renal insufficiency and life threatening lung hypoplasia have developed at term. We report a case of in utero fetal cystoscopy and successful placement of a transurethral vesico-amniotic Double-J (Medical Engineering Corp., New York, New York) stent. Indications, results and the potential benefits of different techniques are discussed. MATERIAL AND METHODS: A 36-year-old woman (primipara) was evaluated at week 26 due to a male fetus with bilateral hydronephrosis, massive distended bladder and an open posterior urethra. Using local anesthesia the fetal bladder was punctured, a 2.6 mm endoscope was inserted and a wire was advanced antegrade through the penis. A 2.8Fr Double-J stent was then placed between the bladder and amniotic cavity. RESULTS: The bladder drained into the amnion, hydronephrosis disappeared and the lung developed normally. At week 37 a healthy infant was delivered who voided spontaneously. CONCLUSIONS: After careful selection of candidates for fetal intervention in obstructive uropathy direct vision fetoscopy and transurethral stent placement can be performed in patients with oligohydramnios, favorable urinary electrolytes and normal appearing kidneys.

Adult↗
PubMed2004

Molecular serological diagnosis in transitional cell bladder cancer.

There are no reliable serological tumor markers for transitional cell carcinoma (TCC) of the urinary bladder. Fluorescent microsatellite analysis (MSA) was used to detect serum-DNA alterations in patients with bladder cancer. Prospectively, fresh tumor-, peripheral blood-, and serum-specimens were collected from 58 consecutive patients treated for TCC of the bladder to obtain the corresponding DNA. DNA was extracted by the phenol-chloroform method from tumors and blood lymphocytes. Serum DNA was isolated by a commercial kit. Fluorescent MSA was performed with a total of 17 polymorphic markers from chromosomal regions 5q, 8p, 9p, 9q, 13q, 14q, 17p, 17q, and 20q in the 58 cancer specimens as well as in specimens from 20 healthy controls. Detection of allelic imbalance and loss of heterozygosity in the tumor and serum specimens was carried out on an automated laser sequencer. Serum-DNA alterations were identified in 79.3% (46/58). Four healthy controls displayed serum-DNA artefacts rendering a specificity of 80%. The highest frequency of serum-DNA alterations (38%) was detected for chromosomal region 8p. Chromosomes 5q, 9p, and 20q showed serum-DNA alterations in 20% to 23%. Identification of tumor-specific serum-DNA alterations was stage independent (P >0.05), but was more frequent in high-grade tumors (P = 0.08). To optimize specificity, simultaneous analysis of tumor DNA is advised to rule out artefacts resembling allelic imbalance in MSA of serum DNA. The method then has potential for application as a "serological marker" in the follow-up of patients after radical surgical therapy for invasive TCC of the bladder.

Carcinoma, Transitional Cell↗
PubMed2003

Giant hydronephrosis mimicking progressive malignancy.

BACKGROUND: Cases of giant hydronephroses are rare and usually contain no more than 1-2 litres of fluid in the collecting system. We report a remarkable case of giant hydronephrosis mimicking a progressive malignant abdominal tumour. CASE PRESENTATION: A 78-year-old cachectic woman presented with an enormous abdominal tumour, which, according to the patient, had slowly increased in diameter. Medical history was unremarkable except for a hysterectomy >30 years before. A CT scan revealed a giant cystic tumour filling almost the entire abdominal cavity. It was analysed by two independent radiologists who suspected a tumour originating from the right kidney and additionally a cystic ovarian neoplasm. Subsequently, a diagnostic and therapeutic laparotomy was performed: the tumour presented as a cystic, 35 x 30 x 25 cm expansive structure adhesive to adjacent organs without definite signs of invasive growth. The right renal hilar vessels could finally be identified at its basis. After extirpation another tumourous structure emerged in the pelvis originating from the genital organs and was also resected. The histopathological examination revealed a >15 kg hydronephrotic right kidney, lacking hardly any residual renal cortex parenchyma. The second specimen was identified as an ovary with regressive changes and a large partially calcified cyst. There was no evidence of malignant growth. CONCLUSION: Although both clinical symptoms and the enormous size of the tumour indicated malignant growth, it turned out to be a giant hydronephrosis. Presumably, a chronic obstruction of the distal ureter had caused this extraordinary hydronephrosis. As demonstrated in our case, an accurate diagnosis of giant hydronephrosis remains challenging due to the atrophy of the renal parenchyma associated with chronic obstruction. Therefore, any abdominal cystic mass even in the absence of other evident pathologies should include the differential diagnosis of a possible hydronephrosis. Diagnostic accuracy might be increased by a combination of endourological techniques such as retrograde pyelography and modern imaging modalities.

Aged↗
PubMed2003

Combining Lithoclast and ultrasound power in one device for percutaneous nephrolithotomy: in vitro results of a novel and highly effective technology.

OBJECTIVES: A new device for percutaneous nephrolithotomy, combining Lithoclast (LC) and ultrasound (US) lithotripsy, was developed. Under standardized in vitro conditions, we evaluated the efficacy of the new technique using artificial stones. Combined application of pneumatic and US lithotripsy was compared with each of the two components alone. METHODS: Five different artificial stones of defined hardness were used. Disintegration was performed under defined pressure in a water bath. The time until the first fragmentation and until complete disintegration to fragments of 2 mm or smaller was measured for LC and US alone and for combined lithotripsy. Furthermore, the disintegrated partition after 1 minute and time until 50% disintegration of each stone was determined. RESULTS: With regard to first fragmentation and complete disintegration, LC and US combination showed superior efficacy. First fragmentation was achieved 25 to 200 times faster and complete disintegration in a range of 11 to 15 minutes. No complete disintegration was possible by LC and US alone within a time limit of 20 minutes. The disintegrated stone mass after 1 minute was 1.5 to 4 times larger in combined lithotripsy and the 50% disintegration time was 30% to 50% compared with LC or US alone. No technical defects occurred. CONCLUSIONS: Combining LC and US in one device for percutaneous nephrolithotomy shows promising in vitro results in an artificial stone model. It seems to provide superior efficacy in the disintegration parameters important for clinical practice.

Equipment Design↗