Biomedical subjects

Dominic Frimberger

Publications and source records attributed to Dominic Frimberger.

17 recordsLinked to original sources

PubMed2006

Risk stratification in penile carcinoma: 25-year experience with surgical inguinal lymph node staging.

OBJECTIVES: In penile carcinoma, the most reliable staging method for lymph node involvement remains radical dissection with its associated high morbidity. However, the patient's prognosis is closely associated with lymph node status, and radical dissection is potentially curative. We report our experience with surgical lymph node staging and evaluate which group of patients could be assigned to a wait-and-see strategy or dynamic sentinel node biopsy and which group should undergo groin dissection. METHODS: From 1979 to 2004, 56 consecutive patients with penile cancer underwent surgical inguinal lymph node staging. On the basis of the histopathologic results, we defined risk stratification into low, high, and intermediate-risk groups according to the clinical examination findings, stage, and grade. RESULTS: Tumor stage (P = 0.019) and tumor grade (P <0.001) correlated significantly with lymph node status. Stratification into low (pT1G1, pT1G2), high (all G3 tumors), and intermediate-risk (all others) groups found 7.7% of low-risk patients with metastases. In the intermediate and high-risk groups, 28.6% and 75.0% had nodal metastases, respectively. Correlation with nodal involvement according to risk group was R2 = 0.608 (P <0.001). CONCLUSIONS: Risk stratification might enable a modified staging strategy for lymph node status according to stage, grade, and clinical examination findings. Highly motivated low-risk patients could be included in a surveillance program; however, high-risk patients should undergo bilateral inguinal dissection. Dynamic sentinel lymph node biopsy might be encouraged for intermediate-risk patients in the future.

Adult↗

PubMed2006

Human embryoid body-derived stem cells in tissue engineering-enhanced migration in co-culture with bladder smooth muscle and urothelium.

OBJECTIVES: To evaluate the affinity between human stem cells and human bladder cells by analyzing their migration and proliferation patterns in co-culture. Human stem cells have great potential for tissue engineering purposes. Co-culture of stem cells with mature cells may promote differentiation. METHODS: Equal numbers of green fluorescent protein-labeled human embryonic germ cell derivates (SDECs) were plated, either alone or in the presence of red fluorescence-labeled (PKH 26) human bladder smooth muscle cells (SMCs) or urothelial cells (UROs). The co-cultures shared the same media (EGM2MV). The migration patterns of the different cell lines were measured daily, using an integrated grid, for 8 days with fluorescence microscopy. RESULTS: SDECs, grown alone, had a robust basal migration rate of between 0.3 and 0.7 mm/day compared with SMCs, which had a rate of 0.1 to 0.3 mm/day and UROs with a rate of 0.1 to 0.2 mm/day. Stem cell migration was enhanced in co-culture with SMCs or UROs to 0.5 to 1.0 mm/day. Migration of SDECs was more linear, directed toward SMCs or UROs, compared with the circumferential growth when plated alone. SMCs, more than UROs, migrated more rapidly in the presence of stem cells. CONCLUSIONS: Human stem cells showed improved migration in the presence of mature human bladder cells and were attracted to them, as shown by the altered direction of growth. Thus, co-culture of human stem cells with host SMCs can enhance seeding of matrices due to positive chemotaxis. Identifying the responsible factors may help to augment chemotaxis between desired cell types and optimize tissue regeneration.

Cell Movement↗

PubMed2006

Synthetic torso for training in and evaluation of urologic laparoscopic skills.

BACKGROUND: The expanding use of advanced minimally invasive surgical techniques demands more advanced training methods, objective measures of resident performance, and more realistic and anatomically correct training models. MATERIALS AND METHODS: A new synthetic torso for urologic laparoscopy training was developed and assessed. The trainer, Lapman, was based on the Visible Human Model and has the exact shape of a human torso. The torso models the outer shape of the body and the abdominal and pulmonary cavities. Animal or synthetic models of the abdominal organs may be placed in the abdominal cavity. An abdominal wall provides access and seals the cavity and can be replaced after repeated punctures with laparoscopic instruments. The thoracic cavity connects to a pneumatic pump to simulate breathing. In order to render realistic mechanic properties, the torso is cast of materials with elastic properties similar to those of soft tissue and incorporates a synthetic skeleton. These similar mechanical properties and the thoracic insufflation create realistic ventilatory motion simulation. RESULTS: Twenty-five individuals--medical students, residents, and attending urologists--participated in a study comparing Lapman with a standard training box. Lapman presented several advantages over the traditional training box, specifically with regard to internal and external views and the incorporation of a realistically shaped abdominal wall. A significant and recurrent theme was the value of the synthetic wall as a tool to gain a greater appreciation of the importance of port placement. Study participants at all levels of training appreciated that Lapman gives a more realistic approximation of the operative procedure. CONCLUSIONS: The novelty of the trainer consists in its anatomic shape, realistic mechanical properties, and ventilatory simulation. This paper reports on its design, construction, and preliminary tests.

Humans↗

PubMed2006

Challenges in a larger bladder replacement with cell-seeded and unseeded small intestinal submucosa grafts in a subtotal cystectomy model.

OBJECTIVE: To evaluate small intestinal submucosa (SIS), unseeded or seeded, as a possible augmentation material in a canine model of subtotal cystectomy. MATERIALS AND METHODS: In all, 22 male dogs had a 90% partial cystectomy and were then divided into three groups. At 1 month after the initial cystectomy, dogs in group 1 (unseeded, six) and group 2 (seeded, six) received a bladder augmentation with a corresponding SIS graft. The dogs in group 3 (ten) received no further surgery and were considered the surgical control group. All dogs were evaluated before and after surgery with blood chemistry, urine culture, intravenous urography, cystograms and cystometrograms. After surgery (at 1, 5 and 9 months), the bladders were examined using routine histology and immunohistochemistry. RESULTS: All 22 dogs survived the subtotal cystectomy, and 18 survived their intended survival period. One dog, in group 2 (seeded), was killed at 1 month after augmentation due to bladder perforation caused by a large piece of incompletely absorbed SIS. Three other dogs (group 1, two; and group 2, one) were killed within 2 months after augmentation due to bladder obstruction by stones. Group 1 and group 2 SIS grafts had moderate to heavy adhesion, graft shrinkage, and some had bone and calcification at the graft site. Histologically, there was limited bladder regeneration in both groups. Interestingly, dogs in group 3 at 1 month after cystectomy (when group 1 and 2 received their augmentations) had severely shrunken bladders and histologically had severe inflammation, fibroblast infiltration and muscle hypertrophy. These results verify the subtotal cystectomy model. CONCLUSIONS: The use of seeded or unseeded SIS in a subtotal cystectomy model does not induce the same quality and quantity of bladder regeneration that is seen in the 40% non-inflammatory cystectomy model. This study provides important insights into the process of regeneration in a severely damaged bladder. The results led us to re-evaluate the critical elements required for a complete bladder replacement using tissue-engineering techniques.

Animals↗

PubMed2006

Inguinal herniation of the bladder in an infant.

Inguinal herniation of the bladder is an uncommon finding with fewer than 200 cases reported in the literature. It is found most commonly in older, obese men with lower urinary tract symptoms. We report a case of inguinal herniation of the bladder in a premature infant.

Comorbidity↗

PubMed2005

Human embryoid body-derived stem cells in co-culture with bladder smooth muscle and urothelium.

OBJECTIVES: Human pluripotent stem cells have excellent regenerative abilities, making them attractive in bladder regeneration. Porcine small intestinal submucosa (SIS) is an established matrix well-suited to the urinary tract. We evaluated the ability of human embryonic germ (hEG) cell-derived stem cells to form a composite graft on SIS, grown alone or in combination with human bladder smooth muscle cells (SMCs) or urothelial (URO) cells. METHODS: The hEG cell-derived cell line SDEC had the best-fit profile for smooth muscle, as determined by its gene and protein expression. SDEC cells were seeded on SIS, either on its serosal or mucosal surface, and cultured for 7 or 14 days. Co-cultures of stem cells with URO cells or SMCs were also assessed under similar conditions. The grafts were analyzed by histologic examination for cell growth, morphology, and matrix penetration. RESULTS: SDEC cells grew in a monolayer on SIS, with a marked increase in three-dimensional growth when co-cultured with URO cells or SMCs. Penetration of the matrix was evident when seeded on the rough surface of the SIS, progressing with time. Stratification of the cell layers occurred on the smooth side of the SIS. CONCLUSIONS: This is the first description of hEG cell-derived stem cells in co-culture with bladder cells. hEG cell-derived stem cells grow well on SIS even when seeded at low concentrations in the presence of bladder cells (URO cells or SMCs). These composite grafts will be ideal to evaluate the in vivo functional characteristics of stem cells using an animal model of bladder regeneration.

Animals↗

PubMed2005

Human embryoid body-derived stem cells in bladder regeneration using rodent model.

OBJECTIVES: To evaluate the capability of a human embryonic germ (hEG) cell-derived cell line (SDEC), previously characterized in our laboratory, seeded on porcine small intestinal submucosa (SIS) to regenerate the injured rat bladder. METHODS: Fluorescent-labeled SDEC cells seeded on SIS for 8 days in vitro were used as bladder grafts in rats. A total of 30 congenitally athymic rats (six groups of 5 rats each), underwent partial cystectomy and replacement with plain SIS (groups 1 to 3) or cell-seeded SIS (groups 4 to 6). The rats were sacrificed after 7 (groups 1 and 4), 14 (groups 2 and 5), and 28 (groups 3 and 6) days. The bladders were analyzed by histopathologic examination and fluorescence microscopy. RESULTS: No graft rejection or diminution in bladder capacity occurred. Plain SIS implants had multiple calcareous deposits, not seen with the cell-seeded implants. Macroscopically, at 7 days, the grafts were healed with a cellular lining on the luminal aspect in groups 4 to 6. Microscopically, the rat bladder was completely regenerated 28 days after stem cell-seeded SIS implantation. Labeled stem cells were identified throughout the graft and contributed significantly to bladder regeneration. CONCLUSIONS: The results of this study have demonstrated the successful replacement of a bladder defect in a rat model using hEG cell-derived cells seeded on SIS grafts. Longer term analysis of these bladder grafts will allow evaluation of function, cell migration, and differentiation processes of human stem cells.

Animals↗

PubMed2005

Variants of the exstrophy complex: a single institution experience.

PURPOSE: Variants of the bladder/cloacal exstrophy complex are rare. Different presentations and subsequent management and outcome are discussed. MATERIALS AND METHODS: We performed a retrospective review of our database of more than 815 patients with the exstrophy complex. Patients with variants of classic epispadias or bladder or cloacal exstrophy were identified. Anatomical presentation, surgical management, type of continence procedures and final outcome were evaluated. RESULTS: Of the 25 patients with variants 13 were treated primarily at our institution and 12 were referred. Time until primary bladder closure ranged from 1 day to 4 years. Followup after continence procedure ranged from 1 month to 39 years. Seven of the 25 patients are awaiting a continence procedure. Six patients are dry without a continence procedure, of whom 4 have superior vesical fistulas. A total of 11 patients underwent bladder neck reconstruction (BNR), of whom 3 are dry, 2 are dry during the day but are wet at night, 1 had a failed procedure and 5 are dry after continent diversion (CD). One additional patient underwent CD initially and is dry. Referred cases of epispadias with bladder prolapse were not recognized at birth and had delayed closure. Impaired bladder growth or failed BNR required CD in 4 patients, and 2 are awaiting a continence procedure. Skin covered and duplicate exstrophy had comparable outcomes to the classic presentations. Duplicated organs were used for reconstructive procedures. Of the 6 patients with cloacal variant 2 are continent of stool and 2 await a Pena procedure. One of these patients has an ileal stoma and 1 has a colostomy. CONCLUSIONS: The initial presentation of exstrophy variants can be confusing, often delaying initial treatment. Superior vesical fistulas permit continence without BNR due to an intact urinary sphincter. Variants such as epispadias with bladder prolapse and duplicate or skin covered exstrophy should be closed at birth with standardized techniques to promote bladder growth for later BNR. These cases are faced with the same long-term problems as the classic presentation. Cloacal variants can present with intact anal innervation, allowing a later Pena procedure.

Abnormalities, Multiple↗

PubMed2005

Growth of bone marrow stromal cells on small intestinal submucosa: an alternative cell source for tissue engineered bladder.

OBJECTIVE: To assess the potential use of bone marrow stromal cell (BMSC)-seeded biodegradable scaffold for bladder regeneration in a canine model, by characterizing BMSCs and comparing them to bladder smooth muscle cells (SMCs) by immunohistochemistry, growth capability, and contractility. MATERIALS AND METHODS: Bone marrow was taken by direct needle aspiration from the femurs of five beagle dogs for the in vitro study. Mononuclear cells were isolated by Ficoll-Paque density gradient centrifugation and cultivated in medium 199 with 10% fetal bovine serum. BMSCs were characterized by cell proliferation, in vitro contractility, immunohistochemical analysis, and the growth pattern on small intestinal submucosa (SIS) scaffolds compared to bladder SMC cultures from the same dogs. Another six dogs had a hemicystectomy and bladder augmentation with BMSC-seeded (two), bladder cells including urothelial cells plus SMC-seeded SIS (two) and unseeded SIS scaffolds (two). The six dogs were followed for 10 weeks after augmentation. RESULTS: In vitro BMSCs had a significant contractile response to calcium-ionophore, with a mean (sem) 36 (2)%, relative contraction (P < 0.01), which was similar to bladder SMCs but markedly different from fibroblasts. BMSCs also expressed alpha-smooth muscle actin by immunohistochemical staining and Western blotting, but did not express desmin or myosin. In vivo, both BMSC-seeded and bladder cell-seeded SIS grafts had solid smooth-muscle bundle formation throughout the graft. CONCLUSIONS: BMSCs had a similar cell proliferation, histological appearance and contractile phenotype as primary cultured bladder SMCs. SIS supported three-dimensional growth of BMSCs in vitro, and BMSC-seeded SIS scaffold promoted bladder regeneration in a canine model. BMSCs may serve as an alternative cell source in urological tissue engineering.

Animals↗

PubMed2005

Ambiguous genitalia and intersex.

Intersex disorders are rare congenital malformations with over 80% being diagnosed with congenital adrenal hyperplasia (CAH). It can be challenging to determine the correct gender at birth and a detailed understanding of the embryology and anatomy is crucial. The birth of a child with intersex is a true emergency situation and an immediate transfer to a medical center familiar with the diagnosis and management of intersex conditions should occur. In children with palpable gonads the presence of a Y chromosome is almost certain, since ovotestes or ovaries usually do not descend. Almost all those patients with male pseudohermaphroditism lack Mullerian structures due to MIS production from the Sertoli cells, but the insufficient testosterone stimulation leads to an inadequate male phenotype. The clinical manifestation of all CAH forms is characterized by the virilization of the outer genitalia. Surgical correction techniques have been developed and can provide satisfactory cosmetic and functional results. The discussion of the management of patients with intersex disorders continues. Current data challenge the past practice of sex reassignment. Further data are necessary to formulate guidelines and recommendations fitting for the individual situation of each patient. Until then the parents have to be supplied with the current data and outcome studies to make the correct choice for their child.

Diagnosis, Differential↗

PubMed2004

Photodynamic therapy of prostate cancer by means of 5-aminolevulinic acid-induced protoporphyrin IX - in vivo experiments on the dunning rat tumor model.

OBJECTIVE: In order to expand the use of photodynamic therapy (PDT) in the treatment of prostate carcinoma (PCA), the aim of this study was to evaluate PDT by means of 5-aminolevulinic acid (5-ALA)-induced protoporphyrin IX (PPIX) in an in vivo tumor model. METHODS: The model used was the Dunning R3327 tumor. First of all, the pharmacokinetics and the localization of PPIX were obtained using fluorescence measurement techniques. Thereafter, PDT using 150 mg 5-ALA/kg b.w. i.v. was performed by homogenous irradiation of the photosensitized tumor (diode laser lambda = 633 nm). The tumors were resected 2 days post-PDT and the extent of the necrosis was determined histopathologically. RESULTS: The kinetics of PPIX fluorescence revealed a maximum intensity in the tumor tissue within 3 and 4.5 h post-application of 5-ALA. At this time, specific PPIX fluorescence could be localized selectively in the tumor cells. The PDT-induced necrosis (n = 18) was determined to be 94 +/- 12% (range 60-100%), while the necrosis of the controls (n = 12) differs significantly (p < 0.01), being less than 10%. CONCLUSION: These first in vivo results demonstrate the effective potential of 5-ALA-mediated PDT on PCA in an animal model.

Aminolevulinic Acid↗

PubMed2003

Risks and complications in 160 living kidney donors who underwent nephroureterectomy.

BACKGROUND: The rate of living donor renal transplantations has increased. However, in view of the possible complications, the question as to whether the condition of the recipient justifies operation of the donor still remains unanswered. The present retrospective study evaluates the perioperative and post-operative risks and complications for the donor at a single major transplantation centre. METHODS: From 1994 to 2001, 160 live donor nephroureterectomies were performed. The median age of living donors was 51 years (range 21-77 years); 19 patients were older than 61 years. After confirming blood group compatibility and negative cross-match, donors underwent an extensive medical and psychological examination. Comorbidities and anatomical features of the donor were evaluated and the impact they may have on the outcome was determined. The nephroureterectomies were performed transperitoneally, with the right kidney being preferred. Pre-operative, intraoperative and post-operative complications were documented. Serum creatinine levels as well as new-onset proteinuria or hypertension were used as criteria for assessing long-term renal function. RESULTS: Complications were observed in 41 donors: 35 were minor and six were major (splenectomy; revisions due to liver bleeding, incarcerated umbilical hernia or infected pancreatic pseudocyst; pneumothorax; and acute renal failure). No patient died. Multiple arteries (14 patients), significant renal artery stenosis (two patients) and additional risk factors (e.g. increased age and previous operations) did not affect the complication rate. In the post-operative follow-up period of 0.5-62 months (mean: 38 months), renal function remained stable in all donors. CONCLUSIONS: Living donor nephrectomy appears to be a safe intervention in specialized centres, where it entails a low morbidity for the donor. Even in high-risk donors, long-term complications were not observed.

Adult↗

PubMed2003

Continent urinary diversions in the exstrophy complex: why do they fail?

PURPOSE: Urinary continence is one of the primary goals in the surgical treatment of the patient with exstrophy. Children with inadequate bladder capacity, noncompliant or neuropathic bladder, or failed bladder neck reconstruction may require creation of a continent urinary reservoir to achieve continence. While initial success rates are excellent, some patients suffer persistent urinary incontinence, severely affecting their quality of life. The reasons for such failure and subsequent management were evaluated. MATERIALS AND METHODS: A retrospective database review was performed in 748 patients with the exstrophy complex. Patients with a history of failed continent urinary diversion with incontinence from the stoma or urethra were identified. Initial diagnosis, number of previous operations, reason for and time interval after surgery when failure occurred, and management strategies were evaluated. RESULTS: Of 92 patients undergoing continent diversion procedures 19 (21%) had failure initially (15 with classic and 4 with cloacal exstrophy). Four of the 19 patients underwent primary surgery at our institution and 15 were referred. The procedure initially performed was an intussuscepted nipple valve in 8 patients, an intussuscepted ileocecal valve in 1 and an ileal or sigmoid reservoir with appendiceal flap valve (Mitrofanoff) in 10. Main reasons for failure included de-intussusception and bladder neck incompetence. Mean followup after continence was achieved was 2.9 years (range 3 months to 10 years). These patients underwent up to 8 operations to achieve continence (mean 5). Most patients (79%) were successfully treated with either 1 (47%) or 2 revisions (32%), while 1 required 3 reoperations. Overall, 89 of 92 patients (97%) are currently continent, including those requiring medications and further surgical procedures, while 3 are still wet. CONCLUSIONS: Most patients with exstrophy with failure of continent urinary diversion have a long complicated surgical history. In this series incontinence from an intussuscepted nipple stoma was mostly due to de-intussusception. In patients with an initial Mitrofanoff stoma all incontinence occurred within the first few months postoperatively. Continence was achieved by either recreation of a Mitrofanoff stoma or bladder neck transection. Patients with a failed continent urinary diversion benefit from careful preoperative evaluation, meticulous surgical execution and persistent attempts to achieve continence.

Adolescent↗

PubMed2003

Female exstrophy: failure of initial reconstruction and its implications for continence.

PURPOSE: Bladder exstrophy is a rare malformation affecting only 1 female out of every 5 patients. In the female initial closure is combined with reconstruction of the outer genitalia, and urinary continence can be achieved by some girls without the need for later bladder neck reconstruction. We evaluated the management and outcome of failed initial closures in the female exstrophy population. MATERIALS AND METHODS: We performed a retrospective database review of patients with the exstrophy complex. Females with classic bladder exstrophy with failure of initial closure were identified. Age at initial closure, use of osteotomies, reasons for failure and number of closures, as well as definitive treatment and long-term outcomes were evaluated. RESULTS: Of 71 females with classic bladder exstrophy 14 had failure of initial closure. Of these patients 1 had undergone initial closure at our institution and 13 were referred for reclosure. Mean followup was 6.5 years (range 3 to 12) and mean age was 10 years (4 to 14). The patients underwent a maximum of 3 closures (mean 2.4). Initial osteotomies were performed in 4 patients, no osteotomy in 8 and status was unknown in 2. Reason for initial failure was dehiscence in 11 patients and prolapse in 3. Five patients underwent a second closure elsewhere. On referral reclosure was successful using osteotomies in all patients. Bladder neck reconstruction was done in 5 patients (3 are daytime continent) and continent diversion in 4 (all are dry). The other patients are awaiting final treatment. CONCLUSIONS: The single most important step to achieve urinary continence is successful initial bladder and posterior urethral closure. Pelvic osteotomies ensure a tension-free closure and enhance bladder outlet resistance. Radical mobilization of the vesicourethral complex allows placement of the bladder deep within the pelvis. Failure of the initial closure in the female exstrophy population has a severe impact on long-term outcome and quality of life.

Adolescent↗

PubMed2002

Role of 5-aminolevulinic acid in the detection of urothelial premalignant lesions.

BACKGROUND: The authors evaluated the role of 5-aminolevulinic acid (5-ALA)-induced fluorescence endoscopy (AFE) in the detection of flat urothelial lesions in light of the suggestions made for flat neoplastic lesions within the 1999 World Health Organization (WHO) classification of urinary bladder tumors. METHODS: From 1995 to 2000, 713 patients underwent 1414 AFE procedures for the detection of transitional cell carcinoma of the bladder (TCCB). Fluorescence imaging was performed with an incoherent light source (D-light; 380-440 nm) that was filtered for efficient protoporphyrin IX excitation and with cystoscopes partially blocking reflected excitation light to enable fluorescence evaluation by a red/blue color contrast 2-3 hours after 50 mL of a 3% solution of 5-ALA was instilled into the bladder. In total, 3834 biopsy specimens (mean, 2.7 specimens per AFE procedure) were taken. RESULTS: Malignant disease was found in 1250 (32.6%) of all biopsies, with 304 biopsies (24.3%) showing carcinoma in situ (cis) and dysplasia II degrees (dys II) according to the previous diagnostic criteria of the WHO. Under prior conventional white-light endoscopy, 30.3% of specimens with dys II and 52.8% of specimens with cis had been missed. CONCLUSIONS: The current results suggest that 5-ALA may be more effective in the detection of flat urothelial lesions than the current diagnostic devices.

Aminolevulinic Acid↗

PubMed2002

Autofluorescence and 5-aminolevulinic acid induced fluorescence diagnosis of penile carcinoma -- new techniques to monitor Nd:YAG laser therapy.

Nd:YAG laser coagulation is possible for superficial tumors of the penis. The value of photodynamic diagnosis (PDD) and autofluorescence imaging (AF) in detecting malignant lesions on the penis was evaluated. Twelve patients with biopsy-confirmed squamous cell cancer (SCC) of the penis were examined with PDD and AF. For the PDD and AF the penis was illuminated with the blue excitation light from a xenon arch lamp. Biopsies were taken from suspicious lesions detected by PDD or AF and then treated with Nd:YAG laser coagulation. Neoplastic lesions presented with a positive red fluorescence under PDD or a diminished appearance under AF. The HPV-analysis was positive in eight of the 12 lesions. Fluorescence diagnosis is used for the detection of neoplastic lesions. It assists the urologist in detecting neoplastic and preneoplastic lesions, ensuring a more reliable destruction of all tumor material in penile sparing surgery.

Aged↗

PubMed2002

Ultraviolet-excited (308 nm) autofluorescence for bladder cancer detection.

OBJECTIVES: To assess the ability of ultraviolet laser-induced autofluorescence for the diagnosis of transitional cell carcinoma of the bladder. METHODS: We studied 43 patients undergoing transurethral resection with recurrent transitional cell carcinoma of the bladder. Guided through 5-aminolevulinic acid-induced fluorescence endoscopy, the autofluorescence of the red fluorescing areas and the adjacent tissue and inconspicuous-appearing mucosa were measured spectroscopically. The autofluorescence excitation was carried out with a xenon chloride excimer laser operating at 308 nm (AF308). For the evaluation of the autofluorescence spectra, an intensity ratio (335/430 nm) was calculated and correlated with the histologic results of the biopsies taken. RESULTS: We analyzed the AF308 spectra of 114 biopsies (21 malignant, 93 benign). The autofluorescence intensity ratios for the benign lesions were a factor of 2 to 7 higher than carcinoma in situ and neoplastic tissue. Therefore, 20 of 21 neoplastic lesions were detected as true positive by AF308. A sensitivity and specificity for AF308 of 95% and 77%, respectively, could be calculated. The sensitivity and specificity for 5-aminolevulinic acid-induced fluorescence endoscopy was 90% and 61%, respectively. By combining the two methods, we calculated a sensitivity of 90% and a specificity of 84%. CONCLUSIONS: The combination of a sensitive imaging technique such as 5-aminolevulinic acid-induced fluorescence endoscopy and a more specific spectral fluorescence probe technique with autofluorescence at 308 nm is a very efficient procedure in the detection of transitional cell carcinoma of the bladder.

Aged↗