Patrick Keller

Dr. Patrick Keller

orcid

Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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25 June 2020 in World Journal of Urology
Verified
Journal Article
Closed access
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GMGiuseppe Magistro
Giuseppe Magistro
PKPatrick Keller
Patrick Keller
TWThilo Westhofen
Thilo Westhofen
MSMelanie Schott
Melanie Schott
ATAlexander Tamalunas
Alexander Tamalunas
CSChristian G. Stief
Christian G. Stief

13 October 2024 in Journal of Clinical Medicine
Verified
Journal Article
Open access
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NPNikolaos Pyrgidis
Nikolaos Pyrgidis
GSGerald Bastian Schulz
Gerald Bastian Schulz
BEBenedikt Ebner
Benedikt Ebner
JJJan-Friedrich Jokisch
Jan-Friedrich Jokisch
LELennert Eismann
Lennert Eismann
YVYannic Volz
Yannic Volz
Background: Radical cystectomy (RC) with the formation of an ileal orthotopic neobladder (ONB) may adversely affect long-term health-related quality of life (HRQOL). An advanced age at the time of ONB construction could further exacerbate the decline in HRQOL. This study aims to establish an evidence-based age threshold at the time of RC with ONB, beyond which a significant deterioration in HRQOL is observed. Methods: We retrospectively analyzed all bladder cancer patients in our department between 2013 and 2022 that fulfilled the EORTC-QLQ-C30 questionnaire preoperatively, as well as at 3 and 12 months after RC with ONB. Patients receiving neoadjuvant or adjuvant chemotherapy or benign/palliative RC were excluded. Results: Overall, 120 patients (81% males) with a mean age of 66 ± 9.6 years underwent RC with ONB and fulfilled the selection criteria. The Global Health Status (GHS) of the EORTC-QLQ-C30 was 64 ± 23 preoperatively, was 64 ± 20 three months postoperatively, and was 68 ± 23 twelve months postoperatively. Overall, 80 (67%) patients presented an increase in GHS at twelve months compared to their preoperative values. The perioperative complications did not differ between patients with decreased and increased GHS. Patients with increased GHS had values of 58 ± 24 preoperatively, 67 ± 19 at 3 months, and 77 ± 16 at 12 months. Patients with decreased GHS had values of 76 ± 16 preoperatively, 57 ± 21 at 3 months, and 50 ± 25 at 12 months. Using ROC analyses with Youden’s index, we defined a threshold of 70 years, after which RC with ONB may lead to worse GHS twelve months postoperatively. Worse continence outcomes were the only perioperative and long-term parameters that predicted worse HRQOL in elderly patients. Conclusions: Based on HRQOL, we suggest that RC with an ileal conduit as a urinary diversion should be recommended in patients older than 70 years.

23 December 2024 in Journal of Clinical Medicine
Verified
Journal Article
Open access
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YVYannic Volz
Yannic Volz
IBIsabel Brinkmann
Isabel Brinkmann
DCDirk Clevert
Dirk Clevert
NPNikolaos Pyrgidis
Nikolaos Pyrgidis
PKPatrick Keller
Patrick Keller
JMJulian Marcon
Julian Marcon
Introduction/Objective: Contrast-enhanced ultrasound (CEUS) is a promising modality for differentiating benign and malignant lesions in various organs, including the testis. Testicular tumors, common in young men, are often treated with radical orchiectomy, which can have significant consequences. This study aimed to analyze CEUS parameters and their association with malignant testicular tumors. Materials and Methods: Between May 2009 and September 2020, 342 patients with suspected testicular lesions underwent CEUS at a tertiary referral center. Multiparametric ultrasound, including B-mode, Color Doppler, CEUS, and elastography, was performed. Exclusion criteria were the absence of a testicular lesion in the CEUS examination. Histological results, CEUS parameters, and elastography data were analyzed, and statistical correlations were evaluated using chi-square and Mann–Whitney U tests, with multivariate logistic regression for significant findings. Results: Of the 342 patients, 114 (33.3%) had suspicious CEUS findings, and 84 underwent surgical exploration. Malignancy was confirmed in 48 cases (57.1%). The sensitivity and specificity of CEUS for detecting malignancy were 93.8% and 85.2%, respectively. Contrast enhancement was observed in 93.3% of malignant tumors, but not statistically significant compared to benign lesions (p = 0.107). However, elastography revealed higher tissue stiffness in 77.8% of malignant tumors versus 41.0% in benign lesions (p = 0.009). Multivariate analysis indicated that tissue stiffness was significantly associated with malignancy (HR 8.29, 95%CI 1.26–54.58, p = 0.028). Conclusions: CEUS is a valuable tool for testicular lesion evaluation, with elastography showing strong potential in predicting malignancy through tissue stiffness. However, contrast enhancement and “wash-in/-out” were not reliable malignancy indicators. Further research is needed to standardize CEUS and elastography techniques for routine clinical use.

22 March 2025 in Journal of Clinical Medicine
Verified
Journal Article
Open access
PDF file
RBRobert Bischoff
Robert Bischoff
JMJulian Marcon
Julian Marcon
GSGerald Bastian Schulz
Gerald Bastian Schulz
CSChristian G. Stief
Christian G. Stief
PKPatrick Keller
Patrick Keller
NPNikolaos Pyrgidis
Nikolaos Pyrgidis
Background: While various techniques for the surgical correction of urethral strictures exist, data on their trends and perioperative outcomes are limited. Methods: Data from the German Nationwide Inpatient Data (GRAND) registry (2005–2023) were used to estimate the trends, baseline characteristics, and perioperative outcomes of the surgical techniques for urethral stricture correction. Results: A total of 500,937 patients underwent surgery. Internal urethrotomy was the most frequently performed procedure (n = 413,095, 82%), followed by urethral dilatation (n = 39,619, 8%), meatoplasty (n = 30,774, 6%), urethroplasty with buccal mucosa (n = 12,351, 2%), urethral excision with primary anastomosis (n = 3428, 0.7%), urethroplasty with preputial skin (n = 1585, 0.3%), and drug-coated balloon dilatation (n = 85, <0.1%). In recent years, internal urethrotomy declined; urethroplasty was relatively stable, and drug-coated balloon dilatation emerged as a promising treatment modality. Internal urethrotomy and urethral dilatation were predominantly performed in older patients (median age of 71 years), while urethroplasty was performed in younger (56 years). Preputial skin urethroplasty had a shorter hospital stay compared to buccal mucosa (−0.4 days, p = 0.02), with no significant differences in transfusion or sepsis rates. Conclusions: Internal urethrotomy remains the most frequently used technique despite declining utilization. Preputial skin urethroplasty presents similar perioperative outcomes compared to buccal mucosa urethroplasty.

2 September 2021 in Journal of Clinical Urology
Verified
Journal Article
Open access
PDF file
ATAlexander Tamalunas
Alexander Tamalunas
TWThilo Westhofen
Thilo Westhofen
MSMelanie Schott
Melanie Schott
PKPatrick Keller
Patrick Keller
MAMichael Atzler
Michael Atzler
GMGiuseppe Magistro
Giuseppe Magistro
Objectives: Holmium laser enucleation of the prostate (HoLEP) can be used regardless of prostate size and offers durable long-term results for patients suffering from lower urinary tract symptoms (LUTS)/benign prostatic obstruction (BPO), with reduced perioperative morbidity. In most western societies almost half of the population are overweight, and obesity itself is often a risk factor for surgical treatment of patients. We therefore analysed the impact of body mass index (BMI) on outcomes and perioperative morbidity in patients undergoing HoLEP for LUTS at our tertiary referral centre. Methods: We retrospectively collected data for 877 patients who underwent HoLEP for LUTS/BPO between 2014 and 2018 and divided patients into group 1 (BMI<25), 2 (BMI 25<30), and 3 (BMI⩾30). We analysed perioperative parameters, safety, and short-term functional outcomes. Results: In preoperative patient characteristics we observed a similar LUTS profile throughout our patient cohorts. The highest proportion of ASA score ⩾III was observed in the obese patient cohort. Enucleation time was significantly prolonged in morbidly obese patients and operative speed was significantly slower, without difference in perioperative complications. Functional outcomes were assessed 30 days post-surgery with significant improvement in IPSS, quality of life (QoL) and Qmax for all groups. Conclusion: Although operating on overweight and obese patients takes significantly longer, HoLEP is efficient and offers acceptable perioperative complication rates even in morbidly obese patients (BMI⩾30). Level of evidence: Not applicable.

29 August 2025 in Journal of Clinical Medicine
Verified
Journal Article
Open access
PDF file
NPNikolaos Pyrgidis
Nikolaos Pyrgidis
DPDaniel Puhr-Westerheide
Daniel Puhr-Westerheide
GSGerald Bastian Schulz
Gerald Bastian Schulz
MFMatthias Philipp Fabritius
Matthias Philipp Fabritius
PKPhilipp M. Kazmierczak
Philipp M. Kazmierczak
PKPatrick Keller
Patrick Keller
Background/Objectives: Prostate artery embolization (PAE) has emerged as a relatively new, minimally invasive alternative for the treatment of benign prostatic hyperplasia. We aimed to compare the perioperative outcomes and trends of PAE versus transurethral resection of the prostate (TURP) and laser enucleation. Materials and Methods: We used the GeRmAn Nationwide inpatient Data (GRAND), provided by the Research Data Center of the Federal Bureau of Statistics, and performed multiple patient-level analyses. Patients with prostate cancer, acute hematuria, and emergent referral to the hospital were excluded. Results: Between 2017 and 2022, a total of 3665 PAEs were performed in Germany compared to 218,388 TURPs and 50,863 laser enucleations. Patients selected for PAE were slightly younger and presented with fewer comorbidities at baseline. The number of laser enucleations increased exponentially in these years, PAEs remained stable, whereas TURPs slightly decreased. Compared to PAE, laser enucleation was associated with higher odds of in-hospital incontinence (4.2% versus 2.7%, OR: 1.6, 95%CI: 1.3–1.9, p < 0.001). On the contrary, PAE was associated with lower odds of in-hospital urinary retention and shorter length of hospital stay compared to TURP (3.2% versus 7.1%, OR: 2.2, 95%CI: 1.8–2.6, p < 0.001, and a 2.6-day difference, 95%CI: 2.5–2.7, p < 0.001, respectively) and laser enucleation (3.2% versus 5%, OR: 1.5, 95%CI: 1.3–1.8, p < 0.001, and a 1.5-day difference, 95%CI: 1.4–1.6, p < 0.001, respectively). Conclusions: PAE offers more favorable perioperative outcomes compared to TURP and laser enucleation, but the use of this relatively new procedure has remained nearly stable in recent years.