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1.
Isr Med Assoc J ; 23(9): 545-549, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34472228

RESUMO

BACKGROUND: Radical cystectomy is a complicated surgery with significant risks. Complications of Clavien-Dindo grade 3-4 range from 25% to 40% while risk of mortality is 2%. Pelvic surgery or radiotherapy prior to radical cystectomy increases the challenges of this surgery. OBJECTIVES: To assess whether radical cystectomy performed in patients with prior history of pelvic surgery or radiation was associated with increased frequency of Clavien-Dindo grade 3 or higher complications compared to patients without prior pelvic intervention. METHODS: We retrospectively evaluated all patients who underwent radical cystectomy at our center over a 7-year period. All patients with pelvic radiation or surgery prior to radical cystectomy comprised group 1, while group 2 included the remaining patients. RESULTS: In our study, 65 patients required radical cystectomy at our institution during the study period. Group 1 was comprised of 17 patients and group 2 included 48 patients. Four patients from group 2 received orthotopic neobladder, while an ileal conduit procedure was performed in the remaining patients. Estimated blood loss and the amount of blood transfusions given was the only variable found to be statistically different between the two groups. One patient from group 1 had four pelvic interventions prior to surgery, and her cystectomy was aborted. CONCLUSIONS: Radical cystectomy may be safely performed in patients with a history of pelvic radiotherapy or surgery, with complication rates similar to those of non-irradiated or operated pelvises.


Assuntos
Cistectomia/métodos , Complicações Pós-Operatórias/epidemiologia , Neoplasias da Bexiga Urinária/cirurgia , Idoso , Idoso de 80 Anos ou mais , Perda Sanguínea Cirúrgica/estatística & dados numéricos , Transfusão de Sangue/estatística & dados numéricos , Cistectomia/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Estruturas Criadas Cirurgicamente , Bexiga Urinária/cirurgia , Neoplasias da Bexiga Urinária/radioterapia , Derivação Urinária/métodos
2.
Bladder Cancer ; 7(2): 187-192, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-38994536

RESUMO

BACKGROUND: Urologic guidelines recommend perioperative instillation of chemotherapy after transurethral resection of bladder tumor (TURBT) to decrease tumor recurrence, yet implementation of this recommendation is partial due to associated morbidity. Hypertonic saline destroys cells by osmotic dehydration and might present a safer alternative. OBJECTIVE: To evaluate the safety of 3% hypertonic saline (Hypersal) intravesical instillation following TURBT in rats and in humans. METHODS: In 8 rats whose bladders were electrically injured, intravesical blue-dyed Hypersal was administered. We measured serum sodium levels before and after instillation and pathologically evaluated their pelvic cavity for signs of inflammation or blue discoloration. Twenty-four patients were recruited to the human trial (NIH-NCT04147182), 15 comprised the interventional and 10 the control group (one patient crossed over). Hypersal was given postoperatively. Serum sodium was measured before, 1 hour and 12-24 hours after instillation. Adverse effects were documented and compared between the groups. RESULTS: In rats, average sodium levels were 140.0 mEq/L and 140.3 mEq/L before and following instillation, respectively. Necropsy revealed no signs of inflammation or blue discoloration. In humans the average plasma sodium levels were 138.6 mEq∖L, 138.8 mEq∖L and 137.7 mEq∖L before, 1 hour and 12-24 hours after instillation, respectively. During the postoperative follow-up there was one case of fever. A month after the surgery, dysuria was reported by 5 patients while urgency and hematuria were reported by one patient each. The most severe adverse events were grade 2 on the Clavien-Dindo scale. Adverse events were similar in the control group. CONCLUSIONS: Hypersal instillation is safe and tolerable immediately after TURBT.

3.
Front Digit Health ; 2: 11, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-34713024

RESUMO

This paper presents a research and development project for studying aging and technology in fall prevention. Falls are an important global health problem in an aging global population. Up to 50% of serious falls may be fatal. Falls result from the cumulative effects of cognitive, musculoskeletal and sensory decline on postural control and substantially affect the activities of daily living, leading to a lower quality of life and physical injury. A near-fall, misstep and a prior fall are established risk factors for a more serious fall. The fear of falling may reduce physical activity and further predispose to falling. However, limitations in the reporting and documentation of fall events create "silent events"-events that are neither documented nor acted upon. An "Age-Techcare" Application (App) was designed using open innovation methods with local older adult populations and health care professionals through a mixed-methodology approach. The App comprised a digital diary for the self-reporting of fall events and an exercise video to strengthen balance as a fall-prevention intervention. The older adults recorded four fall events: a near-fall, the fear of falling, a fall, or no-fall. Prompts to watch the video and the number of times the video was watched were also recorded on the App. Reports retrieved from the App were analyzed after a 10-week pilot study among older adults accessing the App on their smartphones (n = 28) and through their smartTV (n = 23). All participants used the App to self-report fall events. Near-falls were the most frequently reported fall event among both smartphone and smartTV groups. The scale of silent falls (including a fear of falling and near falls) is greater than anticipated (according to prevailing literature) and significant, especially among the older cohort of participants who had previously experienced falls and are living alone. The exercise video was regularly accessed within a self-report-fall-prevention feedback loop. Watching a preventive exercise video clip as a preventive intervention is positively associated with self-reporting of all events. We have shown that the utility and effectiveness of an App in the self-management of fall events to raise self-awareness, document risk and prompt preventive action. As we address the health needs of an aging global population, Apps such as this will need to be further developed and interface with health and social care services. The facility for older adults to negotiate ideas and practices of risk and safety-the hallmark of the aging-in-place and healthy aging discourse-is important to them in their acceptance of dynamic and diverse technology.

4.
World J Urol ; 37(5): 799-804, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30191394

RESUMO

PURPOSE: With the rapidly expanding anatomical and technical knowledge surrounding nervesparing radical prostatectomy (NSRP), anatomical and operative textbooks have failed to keep pace with the literature. A surgical skill laboratory (SSL) was designed to educate urology trainees on surgical anatomy and techniques for NSRP. The objective was to assess the validity of a SSL program. METHODS: A low-fidelity, anatomically accurate prostate model with its appropriate fascial coverings and location of the neurovascular bundle was created. Participants were surveyed prior to a SSL workshop for their knowledge of NSRP focusing on clinical and anatomical considerations. An interactive 2-h tutorial and workshop was then undertaken outlining the clinical and anatomical nuances for NSRP, with participants then practising an intra and inter-fascial NSRP on the model. Participants were resurveyed immediately after the workshop and at 6 months. RESULTS: Thirty participants completed the NSRP workshop. Significant differences (p < 0.0001) in anatomical and clinical knowledge were noted after the workshop with improvements for both junior and senior trainees. The knowledge was retained at 6 months following the workshop. CONCLUSIONS: A low-fidelity bench-top model is a feasible and reproducible technique for improving the understanding of periprostatic anatomy and the different surgical approaches for NSRP. The SSL is useful and knowledge gained appears to be retained by workshop participants. SSL workshops are a valid hands-on approach to teaching surgical skills and should remain an integral part of urology training.


Assuntos
Prostatectomia/educação , Neoplasias da Próstata/cirurgia , Urologia/educação , Competência Clínica , Educação , Humanos , Masculino , Tratamentos com Preservação do Órgão , Nervos Periféricos/anatomia & histologia , Próstata/anatomia & histologia , Próstata/cirurgia , Prostatectomia/métodos , Treinamento por Simulação
5.
Isr Med Assoc J ; 20(10): 642-644, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30324783

RESUMO

BACKGROUND: Almost 50% of patients with germ-cell tumors (GCT) are subfertile, and every step of the treatment may further impair fertility. As a result, sperm banking is often advised prior to radical orchiectomy. However, whether affected testes contribute to fertility is unclear. OBJECTIVES: To determine whether maximal tumor diameter (MTD) is correlated with ipsilateral fertility (IF) in patients treated for GCT. METHODS: We reviewed medical charts for demographic and clinical data of patients with GCT who had undergone orchiectomy at our institution between 1999 and 2015. The extent of spermatogenesis was categorized into three groups: full spermatogenesis, hypospermatogenesis, and absence of spermatogenesis. The presence of mature spermatozoa in the epididymis tail was also assessed. We defined IF as the combination of full spermatogenesis in more than 100 tubules and the presence of mature spermatozoa in the epididymis tail. Mann-Whitney was applied to determine the correlation between MTD and IF. RESULTS: Of 57 patients, IF was present in 28 (49%). Mean patient age was 32.8 years in patients with positive IF and 33.4 years those with negative IF. Seminoma was diagnosed in 46.4% of patients with positive IF and in 65.5% of patients with negative IF. Full spermatogenesis was observed in 33 patients (57.8%). In 48 (82.7%), mature epididymal spermatozoa were found. No correlation was found between MTD and IF. CONCLUSIONS: IF is present in almost half of the patients undergoing radical orchiectomy. Because IF cannot be predicted by MTD, routine pre-orchiectomy sperm banking is suggested.


Assuntos
Neoplasias Embrionárias de Células Germinativas/patologia , Seminoma/patologia , Espermatogênese/fisiologia , Neoplasias Testiculares/patologia , Testículo/patologia , Adulto , Epididimo/fisiologia , Fertilidade/fisiologia , Humanos , Infertilidade Masculina/etiologia , Masculino , Neoplasias Embrionárias de Células Germinativas/cirurgia , Orquiectomia , Estudos Retrospectivos , Seminoma/epidemiologia , Seminoma/cirurgia , Espermatozoides/metabolismo , Estatísticas não Paramétricas , Neoplasias Testiculares/cirurgia , Testículo/metabolismo
6.
Eur Radiol ; 28(10): 4281-4287, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29696431

RESUMO

OBJECTIVES: To evaluate the feasibility and safety of focal therapy for low-intermediate risk prostate cancer (PCa) with magnetic resonance-guided high frequency focused ultrasound (MRgFUS) METHODS: This IRB-approved phase 1 prospective study enrolled eight patients with prostate specific antigen (PSA) ≤ 10 ng/ml, ≤ cT2a and Gleason score ≤ 7 (4 + 3) disease following informed consent. Under MRI guidance, focused high frequency ultrasound energy was delivered to ablate the target tissue. Treatment-related adverse events were recorded. Oncologic outcomes were evaluated with multiparametric MRI, PSA and TRUS biopsy at 6 months following treatment. RESULTS: Ten target lesions [six Gleason 6 lesions, two Gleason 7 (3 + 4) and two Gleason 7 (4 + 3)] were treated in eight men (prostate volume range, 25-50 cc; mean MRI time, 248 min per patient; mean sonication duration, 65 min). Mean target volume was 2.7 cc and mean post-treatment non-perfused volume was 4.3 cc. Quality of life parameters were similar between baseline and 6 months in 6/8 patients. All treated regions were negative on MRI; 4/8 patients and 6/10 target lesions (60%) were clear of disease on biopsy. One patient with 2-mm Gleason 8 disease in one of five cores from treatment site (4 + 3 disease at baseline) subsequently underwent prostatectomy with negative surgical margins. Three patients with low volume (5-15%) Gleason 6 residual disease were offered active surveillance. Mean PSA decreased from 5.06 at baseline to 3.4 ng/ml at 6 months. CONCLUSION: MRgFUS is a feasible and safe method of noninvasively ablating low-intermediate risk PCa with acceptable short-term oncologic outcomes. KEY POINTS: • Focal therapy selectively ablates locally confined, clinically significant index lesion with a margin while sparing rest of gland and adjacent vital structures. • Magnetic resonance-guided focused high frequency ultrasound surgery (MRgFUS) combines MRI with HIFU. • MRgFUS provides ability to monitor treatments in real time and allows a targeted approach for focal ablation. • MRgFUS is a feasible, safe method of noninvasively ablating low-intermediate risk PCa. • MRgFUS provides acceptable oncologic outcomes at 6 months.


Assuntos
Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Imagem por Ressonância Magnética Intervencionista/métodos , Prostatectomia/métodos , Neoplasias da Próstata/cirurgia , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estudos Prospectivos , Neoplasias da Próstata/patologia , Qualidade de Vida , Cirurgia Assistida por Computador/métodos , Ultrassonografia
7.
Eur Urol Focus ; 4(3): 388-394, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28753799

RESUMO

BACKGROUND: CellDetect is a unique histochemical stain enabling color and morphological discrimination between malignant and benign cells based on differences in metabolic signature. OBJECTIVE: The objective of the present study was to validate the performance of this assay in a controlled, blinded, multicenter study. DESIGN, SETTING, AND PARTICIPANTS: The study, conducted in nine hospitals, included patients with documented history of bladder cancer, monitored for urothelial carcinoma (UCC) or scheduled for bladder cancer surgery. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Cystoscopy and/or biopsy were used as a reference standard to determine sensitivity and specificity. Smears were stained by CellDetect and interpreted by two cytologists blinded to the patient's final diagnosis. The findings were compared with those of standard urine cytology and BTA stat. RESULTS AND LIMITATIONS: Two hundred and seventeen voided urine specimens were included. Ninety-six (44%) were positive by histology and 121 (56%) were negative by either cystoscopy or histology. The overall sensitivity of CellDetect was 84%. Notably, the sensitivity for detecting low-grade nonmuscle-invasive bladder cancer tumors was greater than this of BTA stat (78% vs 54%) and more than two-fold higher compared with standard cytology (33%, p ≤ 0.05). The specificity was 84% in patients undergoing routine surveillance by cystoscopy. At a median follow-up of 9 mo, 21% of the patients with positive CellDetect and negative reference standard developed UCC, which was significantly higher compared with the 5% of the true negative cases. Limitations include the lack of instrumental urine samples and the lack of patients with nongenitourinary cancers in the study population. CONCLUSIONS: This study validates the performance of CellDetect as a urine-based assay to identify UCC in patients with history of bladder cancer. The high sensitivity was maintained across all cancer grades and stages without compromising the assay specificity. Further studies are required to test whether this novel stain can be incorporated in routine bladder cancer surveillance as a noninvasive alternative to cystoscopy. PATIENT SUMMARY: Surveillance of bladder cancer requires frequent invasive procedures. In the present study, we validate the ability of a novel biomarker to accurately identify early-stage tumors in urine specimens for the noninvasive monitoring of patients with history of bladder cancer.


Assuntos
Carcinoma de Células de Transição/patologia , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/urina , Bexiga Urinária/patologia , Urotélio/patologia , Idoso , Idoso de 80 Anos ou mais , Bioensaio/métodos , Carcinoma de Células de Transição/cirurgia , Cistoscopia/métodos , Citodiagnóstico/métodos , Detecção Precoce de Câncer/métodos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Bexiga Urinária/cirurgia , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/cirurgia , Coleta de Urina/estatística & dados numéricos , Urotélio/cirurgia
8.
Nat Rev Urol ; 13(11): 641-653, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27670618

RESUMO

Globally, the increased uptake of serum PSA level screening led to an increase in the number of diagnoses of low-risk and intermediate-risk prostate cancer. Traditionally, these patients have been considered for either active surveillance programmes or radical whole-gland therapies, such as prostatectomy or radiotherapy. Focal therapy is an emerging treatment option that involves the focal ablation of prostate cancer with preservation of surrounding healthy tissue. This approach might result in reduced morbidity when compared with whole-gland therapies. In current practice, much controversy surrounds optimal patient selection and preoperative tumour localization strategies. Focal therapy modalities include cryotherapy, high-intensity focused ultrasound, laser ablation, photodynamic therapy, irreversible electroporation, radiofrequency ablation and focal brachytherapy. However, as long-term oncological data for focal therapies are lacking, formal recommendations for its use cannot be made.


Assuntos
Seleção de Pacientes , Neoplasias da Próstata/terapia , Braquiterapia , Ablação por Cateter , Crioterapia , Eletroporação , Ablação por Ultrassom Focalizado de Alta Intensidade , Humanos , Terapia a Laser , Masculino , Gradação de Tumores , Estadiamento de Neoplasias , Fotoquimioterapia , Prostatectomia , Neoplasias da Próstata/patologia , Medição de Risco , Fatores de Risco
9.
AJR Am J Roentgenol ; 205(2): W177-84, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26204305

RESUMO

OBJECTIVE: Focal therapy is an emerging approach to the treatment of localized prostate cancer. The purpose of this study was to report the 6-month follow-up oncologic and functional data of the initial phase 1 trial of patients treated with focal transrectal MRI-guided focused ultrasound in North America. SUBJECTS AND METHODS: Four patients with a prostate-specific antigen (PSA) level of 10 ng/mL or less, tumor classification cT2a or less, and a Gleason score of 6 (3 + 3) were prospectively enrolled in the study and underwent multiparametric MRI and transrectal ultrasound-guided prostate systematic biopsy. Under MRI guidance and real-time monitoring with MR thermography, focused high-frequency ultrasound energy was delivered to ablate the target tissue. The incidence and severity of treatment-related adverse events were recorded along with responses to serial quality-of-life questionnaires for 6 months after treatment. Oncologic outcomes were evaluated with multiparametric MRI and repeat transrectal ultrasound-guided biopsy 6 months after treatment. RESULTS: Four patients with a total of six target lesions were treated and had complications graded Clavien-Dindo I or less. Quality-of-life parameters were similar between baseline and 6-months. All four patients had normal MRI findings in the treated regions (100%), biopsy showed that three patients (75%) were clear of disease in the treated regions, representing complete ablation of five target lesions (83%). All patients had at least one Gleason 6-positive core outside of the treated zone. CONCLUSION: MRI-guided focused ultrasound is a feasible method of noninvasively ablating low-risk prostate cancers with low morbidity. Further investigation and follow-up are warranted in a larger patient series with appropriate statistical analysis of oncologic and functional outcome measures.


Assuntos
Biópsia Guiada por Imagem , Imagem por Ressonância Magnética Intervencionista , Neoplasias da Próstata/cirurgia , Procedimentos Cirúrgicos Ultrassônicos , Ultrassonografia de Intervenção , Idoso , Biomarcadores Tumorais/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estudos Prospectivos , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/patologia , Qualidade de Vida , Inquéritos e Questionários , Resultado do Tratamento
10.
J Magn Reson Imaging ; 42(1): 48-55, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25195664

RESUMO

BACKGROUND: To present our experiences in initial clinical evaluation of a novel mechatronic system for in-bore guidance of needles to the prostate for MRI-guided prostate interventions in 10 patients. We report accuracy of this device in the context of focal laser ablation therapy for localized prostate cancer. METHODS: An MRI-compatible needle guidance device was developed for transperineal prostate interventions. Ten patients underwent MRI-guided focal laser ablation therapy with device-mediated laser fiber delivery. We recorded needle guidance error and needle delivery time. RESULTS: A total of 37 needle insertions were evaluated. Median needle guidance error was 3.5 mm (interquartile range, 2.1-5.4 mm), and median needle delivery time was 9 min (interquartile range, 6.5-12 min). CONCLUSION: This system provides a reliable method of accurately aligning needle guides for in-bore transperineal needle delivery to the prostate.


Assuntos
Ablação por Cateter/instrumentação , Imagem por Ressonância Magnética Intervencionista/instrumentação , Sistemas Microeletromecânicos/instrumentação , Agulhas , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia , Idoso , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Cirurgia Assistida por Computador/instrumentação
11.
JSLS ; 18(3)2014.
Artigo em Inglês | MEDLINE | ID: mdl-25392654

RESUMO

INTRODUCTION: Laparoscopic nephrectomy (LN) is likely the most common laparoscopic procedure performed by general urologists without formal laparoscopic training. The traditional technique is cumbersome because it entails making an early approach to the hilum with the risk of bleeding and need for conversion. We perform a different technique that we believe is simpler to learn and to teach. It consists of a complete dissection of the inferior and posterior aspects of the kidney, followed by en bloc stapling of the renal hilum. The present report is a detailed description of our technique including outcomes and complications. MATERIALS AND METHODS: Perioperative data of 129 consecutive patients who underwent LN between November 2003 and September 2007 were prospectively collected and retrospectively reviewed. Complications were reported using the Clavien classification system, and follow-up was performed according to our institution's protocol and included physical examination, blood count, blood chemistry, and renal function tests at every visit, in addition to abdominal computed tomography scan six months after surgery. Additional imaging was scheduled according to disease stage and grade. RESULTS: Mean patient age, tumor size, and operative time were 63±15.6 years, 6.3±2.4 cm, and 128±41.4 minutes, respectively. Median estimated blood loss was 0 mL (0.200). Conversion to open surgery occurred in 3.1% of patients, and 8% of the patients had a blood transfusion. Complications were recorded in 26% of the patients; 91% of them had Clavien grade scores of 1 or 2. CONCLUSION: We present a standardized technique for LN. Its main advantage is that postpones any manipulation of the hilum to a later step during the procedure when it is easy to identify and control. This decreases early bleeding and main vascular complications.


Assuntos
Neoplasias Renais/cirurgia , Rim/cirurgia , Laparoscopia/métodos , Nefrectomia/métodos , Grampeamento Cirúrgico/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Estudos Retrospectivos
12.
Can Urol Assoc J ; 8(1-2): 47-52, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24578745

RESUMO

INTRODUCTION: Inaccuracy in biopsy Gleason scoring poses a risk to men who may then receive inappropriate treatment. We assess whether there was a change in discordance rates between biopsy and radical prostatectomy at our institution in recent years, while considering the implementation of active surveillance and the shift in biopsy scores caused by the 2005 International Society of Urologic Pathology update to the Gleason scoring protocol. METHODS: We reviewed patients who underwent radical prostatectomy at our institution between May 2004 and April 2011. We analyzed clinical and pathological correlates of upgrading in 3 subgroups: Gleason sum (GS) 6/6, GS6/7 and GS7/7, where the sum preceding the dash was determined from biopsy and the subsequent sum was determined from the radical prostatectomy specimen. We applied the log-rank test and Cox model to a Kaplan Meier analysis of biochemical recurrence in the subgroups, and also mapped GS6/7 discordance over time. RESULTS: In total, 1717 patients met our inclusion criteria. The 3 subgroups had significantly different mean prostate-specific antigen, patient age, tumour volume, margin status, pathologic stage, prostate weight, transrectal ultrasound volume and rate of progression (p < 0.05). We noted a multiphasic trend with a fall in discordance after 2005. However, there was no sustained trend over the study period taken as a whole (p = 0.06). CONCLUSIONS: Although no sustained trend was observed, the falling discordance after 2005 may reflect the accommodation to the Gleason scoring update, while the gradual adoption of active surveillance may have led to the otherwise increasing trends. However, our observations may also be spurious biopsy sampling errors.

13.
Med Phys ; 41(1): 013301, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24387531

RESUMO

PURPOSE: To study the effect of needle placement uncertainty on the expected probability of achieving complete focal target destruction in focal laser ablation (FLA) of prostate cancer. METHODS: Using a simplified model of prostate cancer focal target, and focal laser ablation region shapes, Monte Carlo simulations of needle placement error were performed to estimate the probability of completely ablating a region of target tissue. RESULTS: Graphs of the probability of complete focal target ablation are presented over clinically relevant ranges of focal target sizes and shapes, ablation region sizes, and levels of needle placement uncertainty. In addition, a table is provided for estimating the maximum target size that is treatable. The results predict that targets whose length is at least 5 mm smaller than the diameter of each ablation region can be confidently ablated using, at most, four laser fibers if the standard deviation in each component of needle placement error is less than 3 mm. However, targets larger than this (i.e., near to or exceeding the diameter of each ablation region) require more careful planning. This process is facilitated by using the table provided. CONCLUSIONS: The probability of completely ablating a focal target using FLA is sensitive to the level of needle placement uncertainty, especially as the target length approaches and becomes greater than the diameter of ablated tissue that each individual laser fiber can achieve. The results of this work can be used to help determine individual patient eligibility for prostate FLA, to guide the planning of prostate FLA, and to quantify the clinical benefit of using advanced systems for accurate needle delivery for this treatment modality.


Assuntos
Terapia a Laser/métodos , Agulhas , Neoplasias da Próstata/cirurgia , Incerteza , Humanos , Terapia a Laser/instrumentação , Masculino , Modelos Teóricos
14.
J Cancer Surviv ; 8(2): 190-8, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24317972

RESUMO

PURPOSE: Recent literature has shown that preoperative physical activity (PA) can positively influence surgical outcomes. It is unknown whether the effect of meeting PA guidelines for cancer survivors can impact quality of life following radical prostatectomy for prostate cancer. METHODS: We reviewed our institutional database of prostate cancer outcomes and included patients that underwent radical prostatectomy and completed the Godin-Shephard Leisure Time Exercise Questionnaire (GLTEQ), the Patient-Oriented Prostate Utility Scale (PORPUS), the International Prostate Symptom Score (IPSS), and the five-item International Index of Erectile Function (IIEF). Participants were categorized as meeting or not meeting the American College of Sports Medicine physical activity guidelines for cancer survivors (150 min of moderate intensity or 75 min of vigorous intensity PA per week). Radical prostatectomy outcomes were measured preoperatively and at 6 and 26-weeks postoperatively. RESULTS: From June 2008 to August 2012, 509 men underwent curative, nerve-sparing radical prostatectomy for prostate cancer and completed the GLTEQ, of whom 46% met the PA guidelines. Prior to surgery, men that met the PA guidelines reported higher quality of life (p < 0.001) and erectile function (p = 0.049) than men that did not meet the guidelines. Quality of life at all postoperative timepoints was higher for men that met the PA guidelines after adjusting for age, preoperative body mass index, and surgical approach (p = 0.02). Men that met the PA guidelines were 19% less likely to be incontinent at 6 weeks postoperatively (p = 0.028). CONCLUSION: PA volume may be a useful marker at predicting postoperative recovery of quality of life and urinary incontinence following radical prostatectomy. IMPLICATIONS FOR CANCER SURVIVORS: Cancer survivors should be encouraged to meet PA guidelines prior to surgery in an effort to attenuate the decline in HRQOL and facilitate recovery.


Assuntos
Atividade Motora , Prostatectomia , Neoplasias da Próstata/psicologia , Neoplasias da Próstata/cirurgia , Qualidade de Vida , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Estudos Prospectivos , Neoplasias da Próstata/mortalidade , Sobreviventes
15.
Magn Reson Med ; 70(2): 333-40, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23801423

RESUMO

PURPOSE: A critical requirement of MR-guided interventions is the visualization of an instrument (e.g., catheter, needle) during the procedure. One approach is to fill the instrument with a contrast agent. Previously, the optimization of contrast agent visualization was performed only empirically. In the present study, an analytic optimization of contrast agent SNR efficiency was performed for a spoiled gradient echo pulse sequence. METHODS: Optimal flip angle, repetition time, echo time, and contrast agent concentration were derived analytically. The solution is valid for any contrast agent, provided the relationship between T1 , T2 , and doping concentration is known. RESULTS: Phantom experiments validated the analytic optimization for Gd- and MnCl2 -based contrast agents. Results showed excellent agreement between experimentally predicted and theoretically observed magnetization behavior. In vivo experiments demonstrated optimized contrast agent visualization in brain, heart, and prostate applications. The results demonstrated the large SNR that can be achieved with analytic optimization. As a practical guideline, an 11% dilution of 500 mMol/L Gd-DTPA solution, repetition time ≈ 4 ms, echo time ≈ 1 ms, and θ ≈ 65° was found to provide a large SNR. CONCLUSION: This study derived and validated a method for analytically optimizing contrast agent SNR efficiency. This information may be useful for visualizing instruments during MR-guided interventions.


Assuntos
Algoritmos , Cateterismo/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imagem por Ressonância Magnética Intervencionista/métodos , Compostos Organometálicos/administração & dosagem , Meios de Contraste/administração & dosagem , Humanos , Aumento da Imagem/métodos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
16.
Med Phys ; 40(1): 012304, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23298109

RESUMO

PURPOSE: To demonstrate the capabilities of a new magnetic resonance imaging (MRI)-guided system for delivering needles to the prostate for focal therapy. Included is a presentation of the design of the system and its user interface, evaluation of MR-compatibility, and quantitative evaluation of guidance accuracy and repeatability within the bore of a clinical MRI scanner. METHODS: The use of MRI for visualization of tumors, intraoperative visualization of interventional tools, and thermometry for controlled ablation of lesions is becoming increasingly prevalent. In this work, the authors present a prototype system for guiding needles to prostate tumors within the bore of an MRI scanner for use in focal laser thermal ablation of prostate tumors. The system consists of a manually actuated trajectory alignment device that allows a physician to precisely align a set of needle guides with an intended target in the prostate within the bore of a clinical closed-bore MRI scanner. Needle insertion is then performed transperineally, with the patient in the bore of the MRI, and custom software provides monitoring of thermal ablative procedures. RESULTS: The system is shown to have a minimal effect on image distortion, and only a 6% decrease in image signal-to-noise ratio. Through needle insertion tests in tissue-mimicking phantoms, the system's potential for reliably guiding needles to intra-MR targets within 2.64 mm has been demonstrated. Use of the system to deliver focal laser ablation therapy to two patients showed that it can be used to deliver needles with minimal disruption of workflow, and in less time than when insertions are performed freehand or with a fixed grid template. CONCLUSIONS: A system for delivering needles to a patient's prostate for focal therapy within the bore of an MRI scanner has been developed. Results from needle insertion tests in phantoms suggest that the system has the potential to provide accurate delivery of focal therapy to prostate tumors of the smallest clinically significant size. Initial tests in two patients showed that needle deflection was larger than in phantoms, but methods of manually compensating for this effect were employed and needles were delivered to treatment sites with sufficient accuracy to deliver effective treatment. In addition, the treatment was delivered in less time than with a fixed grid template or freehand insertions. Despite this success, methods of reducing needle deflection are needed in order to fully utilize the potential of this system, and further reduce total procedure time.


Assuntos
Técnicas de Ablação/instrumentação , Imageamento por Ressonância Magnética , Agulhas , Períneo , Neoplasias da Próstata/cirurgia , Cirurgia Assistida por Computador/instrumentação , Desenho de Equipamento , Humanos , Masculino , Razão Sinal-Ruído
17.
Can Urol Assoc J ; 6(6): E283-6, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23283106

RESUMO

The treatment of low-risk prostate cancer is a common clinical dilemma between standard curative whole gland therapy (and its associated quality of life diminishing side effects) and active surveillance (and its low, but real, risk of progression). The goal of focal therapy in low-risk prostate cancer is to achieve the best balance between cancer control and maintenance of quality of life. Magnetic resonance-guided focused ultrasound (MRgFUS) surgery is a non-invasive thermal ablation method that integrates magnetic resonance imaging for target identification, treatment planning and closed-loop control of thermal deposition and focused ultrasound for thermal ablation of the tumour target. This novel transrectal system allows for tumour localization, targeting and monitoring of tumour target ablation in real time, while simultaneously preserving adjacent normal tissue thereby minimizing the side effects of standard curative surgical or radiation therapy. We report the first North American clinical experience of treatment of localized prostate cancer with focal MR-guided transrectal focused ultrasound (clinicaltrial.gov identifier NCT01226576).

18.
Med Image Comput Comput Assist Interv ; 15(Pt 1): 455-62, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23285583

RESUMO

We present a device that has been developed for delivering prostate focal thermal therapy under magnetic resonance imaging (MRI) guidance. Unlike most existing devices, ours is capable of delivering needles to targets in the prostate without removing the patient from the scanner. This feature greatly reduces procedure time and increases accuracy. The device consists of a mechanical linkage encoded with optical incremental encoders, and is manually actuated. A custom magnetic resonance (MR) compatible alignment interface allows the user to manually align the device to its target with high accuracy in-bore in very short time. The use of manual actuation over motors greatly reduces the complexity and bulk of the system, making it much more compact and portable. This is important when dealing with such tight space constraints. Needle targeting experiments in gel phantoms have demonstrated the device's ability to deliver needles with an accuracy of 2.1 +/- 1.3 mm.


Assuntos
Imageamento por Ressonância Magnética/métodos , Próstata/patologia , Neoplasias da Próstata/terapia , Calibragem , Desenho de Equipamento , Géis , Humanos , Masculino , Agulhas , Imagens de Fantasmas , Neoplasias da Próstata/patologia , Reprodutibilidade dos Testes , Robótica , Cirurgia Assistida por Computador/métodos
19.
Future Oncol ; 7(6): 775-87, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21675840

RESUMO

Organ-preserving therapies are widely accepted in many facets of medicine and, more recently, in oncology. For example, partial nephrectomy is now accepted as a preferred alternative over radical nephrectomy for small (up to 4 cm or T1) tumors. Focal therapy (FT) is another organ-preserving strategy applying energy (cryotherapy, laser ablation and/or high-intensity focused ultrasound) to destroy tumors while leaving the majority of the organ, surrounding tissue and structures unscathed and functional. Owing to the perceived multifocality of prostate cancer (PCa) technology limitations, in the past PCa was not considered suitable for FT. However, with the rise of active surveillance for the management of low-risk PCa in carefully selected patients, FT is emerging as an alternative. This is owing to technology improvements in imaging and energy-delivery systems to ablate tissue, as well as the realization that many men and clinicians still desire tumor control. With the postulated ability to ablate tumors with minimal morbidity, FT may have found a role in the management of PCa; the aim of FT a being long-term cancer control without the morbidity associated with radical therapies. Data for FT in PCa have been derived from case series and small Phase I trials, with larger cohort studies with longer follow-up having only just commenced. More data from large trials on the safety and efficacy of FT are required before this approach can be recommended in men with PCa. Importantly, studies must confirm that no viable cancer cells remain in the region of ablation. FT might eventually prove to be a 'middle ground' between active surveillance and radical treatment, combining minimal morbidity with cancer control and the potential for retreatment.


Assuntos
Neoplasias da Próstata/terapia , Conduta Expectante , Ensaios Clínicos como Assunto , Diagnóstico por Imagem , Humanos , Masculino , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/cirurgia
20.
Korean J Urol ; 52(2): 130-5, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21379431

RESUMO

PURPOSE: Understanding of prostate anatomy has evolved as techniques have been refined and improved for radical prostatectomy (RP), particularly regarding the importance of the neurovascular bundles for erectile function. The objectives of this study were to develop inexpensive and simple but anatomically accurate prostate models not involving human or animal elements to teach the terminology and practical aspects of nerve-sparing RP and simple prostatectomy (SP). MATERIALS AND METHODS: The RP model used a Foley catheter with ballistics gelatin in the balloon and mesh fabric (neurovascular bundles) and balloons (prostatic fascial layers) on either side for the practice of inter- and intrafascial techniques. The SP model required only a ripe clementine, for which the skin represented compressed normal prostate, the pulp represented benign tissue, and the pith mimicked fibrous adhesions. A modification with a balloon through the fruit center acted as a "urethra." RESULTS: Both models were easily created and successfully represented the principles of anatomical nerve-sparing RP and SP. Both models were tested in workshops by urologists and residents of differing levels with positive feedback. CONCLUSIONS: Low-fidelity models for prostate anatomy demonstration and surgical practice are feasible. They are inexpensive and simple to construct. Importantly, these models can be used for education on the practical aspects of nerve-sparing RP and SP. The models will require further validation as educational and competency tools, but as we move to an era in which human donors and animal experiments become less ethical and more difficult to complete, so too will low-fidelity models become more attractive.

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