Biomedical subjects

D Frimberger

Publications and source records attributed to D Frimberger.

14 recordsLinked to original sources

PubMed2006

Lymphoscintigraphy in penile cancer: limited value of sentinel node biopsy in patients with clinically suspicious lymph nodes.

The staging lymph node dissection in patients with penile carcinoma is accompanied with a high morbidity. As many patients are free of nodal metastases the lymphoscintigraphic sentinel node biopsy is supposed to minimize perioperative morbidity in these patients. In the current study the accuracy of the lymphoscintigraphic sentinel node biopsy was verified against the gold standard of radical inguinal dissection. In particular, patients with enlarged lymph nodes have also been included since one half of these patients is known to have histologically negative lymph nodes. Between 2000 and 2004 fifteen patients with penile carcinoma were elected to undergo bilateral groin dissection, thus 30 inguinal areas have been dissected. Nine patients have had clinically palpable nodes. All patients underwent lymphoscintigraphy after injection of Tc99-nanocolloid subcutaneously into the peritumoral area. Intraoperatively the sentinel nodes were identified with the aid of a gamma ray detection probe and excised. Afterwards a standard groin dissection was performed and the different lymph nodes were histopathologically assessed separately. In all patients lymph nodes with high radioactivity uptake were detected bilaterally. In 10 out of 30 inguinal areas histopathologically positive lymph nodes were present. In four of them the sentinel node was positive for tumor but in six dissection areas lymph node metastases were found despite a negative sentinel node. These patients had clinically palpable lymph nodes in their histologically positive inguinal regions. If no palpable nodes were present dynamic sentinel biopsy detected the positive nodes. The current study showed that dynamic sentinel node biopsy in patients with clinically suspicious lymph nodes is of low value for detection of lymphatic spread in penile cancer. Therefore the gold standard in these patients remains the radical groin dissection. However, dynamic sentinel node biospy is still a promising strategy to identify lymphatic spreading in clinically N0 patients and therefore to prevent unnecessary groin dissection.

Adult↗

PubMed2005

Reconstructive lower urinary tract surgery in incontinent adolescents with exstrophy/epispadias complex.

OBJECTIVES: To outline the management strategies applied to the adolescent patient population with exstrophy/epispadias and incontinence at our institution. These patients present a difficult management problem. At the same time they are dealing with difficult issues, including body image and sexual awareness, the added burden of ongoing incontinence causes major anxieties and lifestyle restrictions. In many, incontinence has persisted despite numerous operations. METHODS: A total of 25 (19 male and 6 female) patients who remained incontinent into adolescence or early adulthood were reviewed. Of the 25 patients, 19 had exstrophy, 4 had cloacal exstrophy, and 1 male and 1 female had epispadias. Six patients had undergone eight prior attempts at continent reconstruction, one had undergone cutaneous diversion, and one had problems after ureterosigmoidostomy. RESULTS: The mean age at continence surgery was 12.9 years. Of the 25 patients, 18 underwent bladder augmentation, with a continent stoma in 17 and an artificial sphincter in 1. An additional 5 patients underwent bladder neck transection, with a new continent stoma in 3. The ureterosigmoidostomy was converted to a Mainz II pouch. One patient underwent continent neobladder formation. Nine patients (36%) developed complications during follow-up. Three required stoma revision for stenosis and one for prolapse. Pouch stones occurred in 4 patients, and vesicocutaneous fistula developed in 1. All achieved full urinary continence. The mean follow-up was 72.4 months. CONCLUSIONS: Some children with exstrophy/epispadias reach adolescence and remain incontinent. For these patients, modern reconstructive techniques provide hope of continence. With careful preoperative assessment, exact surgical precision, and regular follow-up, a successful outcome can be expected in virtually all cases without the need for external urine collection devices.

Adolescent↗

PubMed2005

Polyps in the exstrophic bladder. A cause for concern?

PURPOSE: The role of environmental injury in carcinogenesis is widely recognized. Malignancy in exstrophic bladders has been reported most frequently in untreated adults and those undergoing surgical treatments which involve the mixing of fecal and urinary streams. The question of whether the closed exstrophic bladder has a similar potential for malignancy has not been resolved. The polypoid appearance of the exstrophic bladder template raises the concern of premalignant lesions. We characterized the histology of these lesions and analyzed their microscopic features with particular reference to predisposition for dysplasia. In doing so, we attempt to address the aforementioned question and set the stage for definitive quantification of the risk of malignancy in these patients with careful, long-term followup. MATERIALS AND METHODS: Under institutional board review, the slides of 38 patients with classic bladder exstrophy who had polyps excised at the time of closure were reviewed by a single genitourinary pathologist (JIE). The most common findings were reported for polyps resected at primary and secondary closure, respectively, and a comparative analysis was performed. RESULTS: Of the 38 cases 24 were primary closures and 14 were secondary closures. Six of the primary closures were delayed by 6 weeks or greater. The 2 basic types of polyps observed were fibrotic and edematous. Both types were associated with overlying reactive squamous metaplasia in approximately 50% of cases. Varying degrees of fixed on file Brunn's nests, cystitis cystica and cystitis glandularis were noted. Cystitis glandularis was observed in a significantly greater percentage of secondary closures (p = 0.0014). CONCLUSIONS: Although no dysplasia was noted, cystitis glandularis is associated with the development of adenocarcinoma of the bladder. The finding of cystitis glandularis suggests a more severe epithelial injury and it follows that the significant majority of these cases (10 of 14, 71.4%) were observed with polyps resected during secondary closure. These patients warrant future surveillance with urine cytology and cystoscopy as they enter adult life.

Bladder Exstrophy↗

PubMed2004

[Embryonic and adult stem cells for tissue engineering in urology].

Stem cells are considered a possible alternative treatment for degenerative diseases. Parkinson's disease and diabetes mellitus may become curable using stem cells. The term "stem cell" is used very broadly, although it has been well defined. Undifferentiated cells (stem cells and progenitor cells) are isolated from prenatal and postnatal tissues. This review provides an overview of embryonic and adult stem cells and describes potential applications in the field of tissue engineering in urology.

Adult↗

PubMed2003

Fluorescence diagnosis: a novel method to guide radical inguinal lymph node dissection in penile cancer.

In penile cancer there is still a diagnostic dilemma between over treatment of lymph node-negative patients and the missing of occult metastases by watchful waiting. In the current study the value of fluorescence diagnosis during radical inguinal lymph node dissection was evaluated. Five patients with penile cancer were elected to undergo groin dissection. All patients received 5-aminolevulinic acid (5-ALA) orally before the operation for fluorescence diagnosis. Intraoperatively, fluorescence detection of the lymph nodes was performed by visual detection and spectroscopy. Two of the five patients had positive inguinal lymph nodes. Fluorescence in tumor-bearing tissue was detectable in the exposed lymph nodes. Protoporphyrin IX (PPIX) is accumulated in tumor-positive lymph nodes, making fluorescence diagnosis in penile cancer possible. More studies with higher patient numbers are necessary to evaluate optimal dosage and excitation conditions to detect tumor-bearing nodes in vivo.

Fluorescence↗

PubMed2003

[Papules, fungi, protozoa--or cancer? Many skin conditions of the penis can be confirmed with biopsy].

The male genitals can be affected by infections, neoplastic and inflammatory dermatoses. This means that numerous diseases have to be included in differential diagnostic considerations to discriminate premalignant from malignant penile tumors. Basically, penile carcinoma cannot be excluded by clinical examination alone. Apparently clinically benign penile lesions may be the cause of a misdiagnosis persisting of lengthy periods. Therefore, the correct diagnosis should be confirmed by timely biopsy whenever there is a doubt. The identification of known risk factors and the early detection and treatment of all precancerous lesions are indispensable for preventing cancer of the penis.

Biopsy↗

PubMed2003

Recurrence of condylomata acuminata of the urethra after conventional and fluorescence-controlled Nd:YAG laser treatment.

OBJECTIVES: To report our experience with conventional and fluorescence-controlled neodymium:yttrium-aluminum-garnet (Nd:YAG) laser therapy of urethral condylomata. Urethral condylomata can sometimes only be reached by endoscopy and are in general very susceptible to recurrence. They must therefore be considered as a therapeutic problem that has not yet been resolved. METHODS: One hundred sixty-eight patients with urethral condylomata were treated with the Nd:YAG laser (93 men using conventional white-light endoscopy and 75 men using fluorescence control after topical application of 5-aminolevulinic acid). The relapse characteristics were investigated according to the location and extent of the urethral lesions and with regard to the different endoscopy techniques. RESULTS: Of all patients, 35.7% developed recurrences of urethral condylomata after laser therapy. These were mainly located on the meatus and in the distal urethra. Only 4.8% of patients had proximal condylomata, and this was only seen in people with distal urethral involvement. Extensive, complete, or semicircularly arranged condylomata developed recurrence and complications (eg, strictures) more frequently after laser therapy. Significantly fewer recurrences (21.3% versus 47.3%) were observed in fluorescence-controlled laser therapy in a retrospective comparison with laser therapy under conventional conditions with a corresponding extent of human papillomavirus lesions. CONCLUSIONS: Nd:YAG laser therapy enables a specific topical clearance of human papillomavirus lesions at different locations in the urethra. 5-Aminolevulinic acid-induced fluorescence diagnostics enhances the effectiveness of Nd:YAG laser therapy of human papillomavirus lesions. Urethral instrumentation of any kind leads to viral contamination of the proximal urethra.

Administration, Topical↗

PubMed2002

[Telerobotic surgery between Baltimore and Munich].

The rapid development of laparoscopy in urology necessitates the training of specialists to guarantee the high standard of patient care. The real-time data communication of medical information between physicians in different locations is known as telemedicine. Telementoring describes the assistance of an experienced surgeon, while telerobotics requires the use of robots. Two robots, the established AESOP and the PAKY + RCM developed at the Johns Hopkins Hospital (JHH), were used to perform a telerobotic laparoscopic renal cyst ablation in cooperation between Baltimore and Munich. The telementor maneuvered the robots over a distance of 8000 km using eight ISDN lines and a PC. AESOP moved the camera, while PAKY allowed the use of a fan retractor in the abdomen. The telerobotic operation was performed without complications or system and communication failures. Telementoring can be used for training purposes but also for consultation between specialists in emergency settings.

Baltimore↗

PubMed2002

Penile carcinoma. Is Nd:YAG laser therapy radical enough?

PURPOSE: Penile carcinoma is a difficult disease to treat due to its aggressive nature and the psychological effects of amputation, which is often the recommended therapy. Outcome data from the last 13 years on patients with penile carcinoma treated with Nd:YAG laser coagulation were evaluated and compared with outcome data on conventional organ sparing techniques. MATERIALS AND METHODS: For the last 13 years 29 patients were treated with Nd:YAG laser coagulation, including 17 with carcinoma in situ, and 10 with stage T1 and 2 with T2 cancer. Mean patient age was 55.1 years and mean followup was 46.7 months. RESULTS: All patients are alive. Disease recurred in 1 patient with T1 tumor and 1 with carcinoma in situ. All patients were satisfied with the cosmetic and functional result. CONCLUSIONS: Recurrence rates after Nd:YAG laser treatment for T1 tumors are comparable to those after partial amputation. Excellent cosmetic and functional results can be achieved without compromising oncological principles. For patients with metastasis prognosis is limited by the distant disease and, therefore, amputation is only necessary to achieve local control.

Adult↗

PubMed2001

Endoscopic detection of transitional cell carcinoma with 5-aminolevulinic acid: results of 1012 fluorescence endoscopies.

OBJECTIVES: The initial encouraging results using 5-aminolevulinic acid (5-ALA) induced fluorescence endoscopy (AFE) have promised a procedure with an outstanding sensitivity for the detection of early stage bladder cancer. Summarized here is our clinical experience and data comprising 1012 fluorescence endoscopies. METHODS: Two hours, 30 minutes before endoscopy, 1.5 g 5-ALA dissolved in 50 mL of 5.7% sodium monohydrogen phosphate was instilled in patients intravesically. Before AFE, all patients underwent white light endoscopy, and a bladder washing cytologic specimen was obtained. A special light source provided blue light (375 to 440 nm) for fluorescence excitation. Suspicious sites were identified by their red fluorescence contrasting against backscattered blue light when observed through the long pass filter (445 nm) integrated into the telescope eyepiece. RESULTS: Two thousand four hundred seventy-five specimens were obtained (2.4 biopsies per AFE). In 552 AFEs (54.5%), neoplastic urothelial lesions were detected, in 34.2% only because of their positive fluorescence; 38.7% of these additionally detected neoplastic foci had poorly differentiated histologic features. CONCLUSIONS: AFE has proved to be a clinically feasible procedure with an outstanding detection rate for flat, urothelial, high-risk lesions.

Administration, Intravesical↗

PubMed2001

Autofluorescence imaging to optimize 5-ALA-induced fluorescence endoscopy of bladder carcinoma.

OBJECTIVES: To design an optical system for detecting autofluorescence (AF) of bladder tumors and to determine the success of reducing the false-positive rate of 5-aminolevulinic acid-induced fluorescence endoscopy (AFE). AFE provides significantly higher sensitivity in detecting and localizing bladder carcinoma compared with white light endoscopy. The specificity of AFE is equivalent to white light endoscopy, mostly because of the false-positive fluorescence of chronic cystitis lesions. Laser-induced spectral autofluorescence detection is also an efficient method in the diagnosis of bladder carcinoma. METHODS: Bladder tissue was excited to AF using the D-Light (375 to 440 nm) after regular AFE with detection of fluorescence-positive areas. The optical image was produced using a special RGB camera. Biopsies were taken from AFE-positive areas, the peritumoral edges, and normal bladder mucosa. The AF images of the suspicious areas were compared with the AFE images and the histologic results. RESULTS: A total of 43 biopsies were histologically examined (24 benign and 19 neoplastic). AF imaging showed contrast differences between papillary tumors, flat lesions, and normal mucosa. The combination of AFE with AF raised the specificity of AFE alone from 67% to 88%. CONCLUSIONS: AF imaging is possible. The value of the method in reducing the false-positive rate of the highly sensitive AFE needs to be validated with higher numbers. The combination of AF with AFE had a 20% higher specificity than AFE alone in our study.

Administration, Intravesical↗

PubMed2001

Use of hydro-jet cutting for laparoscopic partial nephrectomy in a porcine model.

OBJECTIVES: To evaluate whether a laparoscopic hydro-jet device can provide a safe and effective partial nephrectomy. Partial nephrectomy is still one of the most challenging operations in urologic laparoscopy. The control of hemorrhage is very difficult to achieve with laparoscopic techniques. In open surgery, hydro-jet resection is used to cut the renal parenchyma selectively, avoiding damage to the vascular structures or collecting system.Methods. Laparoscopic wedge, as well as pole, resections of the kidney were performed in 5 pigs under general anesthesia. After exposure of the kidney, the renal capsule was incised using electrocautery. The hydro-jet was then used to dissect the renal parenchyma. In pole resections, the collecting system and central vessels were divided using an Endo-GIA. Hemostasis was achieved by electrocoagulation or clips. The dissection time and intraoperative complications were evaluated.Results. The operations were performed successfully in all animals without temporary ischemia. The hydro-jet generator allowed precise and effective tissue dissection without significant hemorrhage. The parenchymal vessels were selectively coagulated. The collecting system and central vessels remained intact and could be divided after application of the Endo-GIA. The mean dissection time was 42 +/- 6 minutes for the wedge resections and 54 +/- 8 minutes for the pole resections. CONCLUSIONS: These experimental results demonstrate the suitability of hydro-jet dissection for safe laparoscopic partial nephrectomy without temporary ischemia and with reduction of the operative trauma to the kidney. On the basis of our own experiences with other techniques, including electrocautery and laser technology for partial nephrectomy, we conclude that laparoscopic hydro-jet resection represents an interesting alternative to other techniques.

Animals↗

PubMed2001

Quantification of 5-aminolevulinic acid induced fluorescence improves the specificity of bladder cancer detection.

PURPOSE: 5-Aminolevulinic acid induced fluorescence endoscopy has outstanding sensitivity for detecting early stage bladder cancer. Nevertheless, a third of the lesions that show specific fluorescence are histologically benign. We decreased the false-positive rate of 5-aminolevulinic acid induced fluorescence endoscopy by incorporating protoporphyrin IX fluorescence quantification into the standard cystoscopy procedure. MATERIALS AND METHODS: In 25 cases (53 biopsies) of a history of or suspicion for bladder cancer 5-aminolevulinic acid induced fluorescence endoscopy and fluorescence image quantification were performed. For fluorescence image quantification images obtained with a target integrating color charge-coupled device camera were digitized and stored in a personal computer. Red-to-blue ratios were calculated from fluorescence positive lesions and results were correlated with hematoxylin and eosin histology. RESULTS: Malignant fluorescence positive lesions showed significantly stronger fluorescence intensity than fluorescing lesions with benign histology. A threshold was established that decreased the false-positive rate by 30% without affecting sensitivity. CONCLUSIONS: Fluorescence image quantification is a new endoscopic method for objectively selecting multicolor fluorescence bladder lesion images for biopsy. It has the potential of eliminating human error by different surgeons with variable experience in fluorescence endoscopy.

Adult↗

PubMed2000

Endoscopic fluorescence diagnosis and laser treatment of transitional cell carcinoma of the bladder.

Recurrent bladder cancer is due to tumor cell implantation, incomplete resection, and multicentric neoplastic changes throughout the bladder. The possibilities of 5-Aminolevulinic acid-induced fluorescence endoscopy (AFE), a highly sensitive method in detecting bladder cancer and laser energy as treatment to lower the recurrence rate in bladder cancer, are evaluated. After intravesical administration of AFE Protoporphyrin IX, a tumor-selective manner is excited by a xenon-arc lamp (wavelength 400 to 410 nm) to emit red fluorescence. Suspicious lesions can be detected by their red fluorescence and are electroresected or treated with laser energy. Complete resection or destruction of all tumors in the bladder is crucial to prevent recurrent and invasive growth of transitional cell carcinoma. AFE detects malignant lesions in the bladder with a sensitivity of 98% and Cis in 100%, respectively. Laser treatment of superficial bladder cancer lowers the local recurrence rate and reduces the risk of viable tumor cell implantation.

Aminolevulinic Acid↗