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Sample records for laser enucleation vapoenucleation

  1. Are Histological Findings of Thulium Laser Vapo-Enucleation Versus Transurethral Resection of the Prostate Comparable?

    PubMed

    Carmignani, Luca; Macchi, Alberto; Ratti, Dario; Finkelberg, Elisabetta; Casellato, Stefano; Bozzini, Giorgio; Maruccia, Serena; Marenghi, Carlo; Picozzi, Stefano

    2015-09-01

    We investigated if an adequate histological diagnosis can be made from tissue after Thulium laser vapo-enucleation of the prostate (ThuVEP) and whether it is comparable to transurethral prostate resection (TURP) tissue findings in patients with symptomatic benign prostatic hyperplasia. We analyzed 350 ThuLEP and 100 matched TURP tissue specimens from patients who underwent one of the two procedures between January 2009 and June 2014. Thulium Laser Enucleation of Prostate (ThuVEP) was combined with mechanical morcellation of the resected lobe. Each histological specimen was reviewed by two pathologists. Preoperative prostate ultrasound volume, total serum prostatic specific antigen and postoperative tissue weight were evaluated. Microscopic histological diagnosis was assessed by standard histological techniques and immunohistochemical evaluation. Patients were comparable in terms of age and preoperative total serum prostate specific antigen. Incidental adenocarcinoma and high grade PIN of the prostate were diagnosed in a comparable percent of specimens in the 2 groups (2.5 % in the ThuVEP group versus 3 % in the TURP group). Tissue thermal artifacts induced by the Thulium laser are mostly due to coagulation as that of the conventional monopolar diathermy in TURP. Tissue quality was maintained in the ThuVEP histological specimens. Tissue maintain histological characteristics and proprieties without modification for successive immunoistochemical analysis. The pathologist ability to detect incidental prostate cancer and PIN was maintained even if there is a quoted of vaporized tissue. PMID:25862670

  2. A review of thulium laser vapo-enucleation of the prostate: A novel laser-based strategy for benign prostate enlargement.

    PubMed

    Jones, Patrick; Rai, Bhavan Prasad; Somani, Bhaskar K; Aboumarzouk, Omar M

    2015-09-01

    Thulium laser vapo-enucleation of the prostate is the latest addition to the arsenal of minimally invasive therapies available for the surgical treatment of lower urinary tract symptoms secondary to benign prostate hyperplasia. The potential advantages include smoother vaporisation, a clearer visual field and the option of both continuous-wave and pulsed modes, which also potentiate the haemostatic properties of this endoscopic method. Short-term results show that it yields significant improvements in both subjective and objective outcomes, with a strong safety profile. Large-scale randomised studies with a longer follow-up are warranted to determine the durability of this laser procedure. PMID:26413349

  3. A review of thulium laser vapo-enucleation of the prostate: A novel laser-based strategy for benign prostate enlargement

    PubMed Central

    Jones, Patrick; Rai, Bhavan Prasad; Somani, Bhaskar K.; Aboumarzouk, Omar M.

    2015-01-01

    Thulium laser vapo-enucleation of the prostate is the latest addition to the arsenal of minimally invasive therapies available for the surgical treatment of lower urinary tract symptoms secondary to benign prostate hyperplasia. The potential advantages include smoother vaporisation, a clearer visual field and the option of both continuous-wave and pulsed modes, which also potentiate the haemostatic properties of this endoscopic method. Short-term results show that it yields significant improvements in both subjective and objective outcomes, with a strong safety profile. Large-scale randomised studies with a longer follow-up are warranted to determine the durability of this laser procedure. PMID:26413349

  4. Efficacy and Safety of 120-W Thulium:Yttrium-Aluminum-Garnet Vapoenucleation of Prostates Compared with Holmium Laser Enucleation of Prostates for Benign Prostatic Hyperplasia

    PubMed Central

    Hong, Kai; Liu, Yu-Qing; Lu, Jian; Xiao, Chun-Lei; Huang, Yi; Ma, Lu-Lin

    2015-01-01

    Background: This study compared the efficacy and safety between 120-W thulium:yttrium-aluminum-garnet (Tm:YAG) vapoenucleation of prostates (ThuVEP) and holmium laser enucleation of prostates (HoLEP) for patients with lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia (BPH). Methods: A retrospective analysis of 88 consecutive patients with symptomatic BPH was carried out, who underwent either 120-W ThuVEP or HoLEP nonrandomly. Patient demographics and peri-operative and 12-month follow-up data were analyzed with the International Prostate Symptom Score (IPSS), quality of life (QoL) score, maximum flow rate (Qmax), postvoid residual urine volume (PVR), and rates of peri-operative and late complications. Results: The patients in each group showed no significant difference in preoperative parameters. Compared with the HoLEP group, patients in the 120-W ThuVEP group required significantly shorter time for laser enucleation (58.3 ± 12.8 min vs. 70.5 ± 22.3 min, P = 0.003), and resulted in a significant superiority in laser efficiency (resected prostate weight/laser enucleation time) for 120-W Tm:YAG laser compared to holmium:YAG laser (0.69 ± 0.18 vs. 0.61 ± 0.19, P = 0.048). During 1, 6, and 12 months of follow-ups, the procedures did not demonstrate a significant difference in IPSS, QoL score, Qmax, or PVR (P > 0.05). Mean peri-operative decrease of hemoglobin in the HoLEP group was similar to the ThuVEP group (17.1 ± 12.0 g/L vs. 15.2 ± 10.1 g/L, P = 0.415). Early and late incidences of complications were low and did not differ significantly between the two groups of 120-W ThuVEP and HoLEP patients (P > 0.05). Conclusions: 120-W ThuVEP and HoLEP are potent, safe and efficient modalities of minimally invasive surgeries for patients with LUTS due to BPH. Compared with HoLEP, 120-W ThuVEP offers advantages of reduction of laser enucleation time and improvement of laser efficiency. PMID:25836607

  5. A prospective, randomized comparison of a 1940 nm and a 2013 nm thulium: yttrium–aluminum–garnet laser device for Thulium VapoEnucleation of the prostate (ThuVEP): First results

    PubMed Central

    Tiburtius, Christian; Gross, Andreas J.; Netsch, Christopher

    2015-01-01

    Introduction: We report the early postoperative results of the first prospective, randomized comparison of two commercially available thulium lasers with different wavelengths for the treatment of benign prostatic obstruction (BPO). Materials and Methods: From January to June 2013, 80 consecutive patients were randomized for Thulium VapoEnucleation of the prostate (ThuVEP) with a 2013 nm (RevoLix®) (n = 39) or a 1940 nm (Vela®XL) (n = 41) thulium laser. Preoperative status, surgical details and the immediate outcome were recorded for each patient. The perioperative complications were assessed and classified according to the modified Clavien classification system. Results: Median operation time, resected tissue, percentage of resected tissue, catheter time, overall operation efficiency and Hb loss differed nonsignificantly between both devices (P > 0.05). At discharge, the median maximum urinary flow rate and postvoiding residual (PVR) urine improved significantly in both groups (P < 0.001). The PVR was lower in the 1940 nm ThuVEP group (P ≤ 0.034). Perioperative complications occurred in 18 (22.5%) patients (Clavien 1: 12.5%; Clavien 2: 5%, Clavien 3b: 2.5%, Clavien 4a: 2.5%), with no differences between the groups (P = 0.5). Conclusions: The 1940 nm and the 2013 nm thulium lasers are both safe and effective for the treatment of BPO with ThuVEP. Both lasers give equivalent and satisfactory immediate micturition improvement with low perioperative morbidity. PMID:25624576

  6. Outcomes following Thulium vapoenucleation of large prostates

    PubMed Central

    Pearce, Shane M.; Pariser, Joseph J.; Malik, Rena D.; Famakinwa, Olufenwa J.; Chung, Doreen E.

    2016-01-01

    ABSTRACT Introduction: Thulium laser VapoEnucleation of the prostate (ThuVEP) is an evolving surgical technique for BPH. Most studies have focused on outcomes in small to medium sized prostates and have originated from Europe and Asia. We sought to describe our experience with ThuVEP for very large prostates in a North American cohort. Materials and Methods: From December 2010 to October 2014, 25 men underwent ThuVEP using the CyberTM® (Quantastem, Italy) thulium laser, all with prostate volume >75mL. Data collected included patient demographics, comorbidities, intraoperative parameters, complications, and post-operative outcomes including maximum flow rate (Qmax), post-void residual (PVR), International Prostate Symptom Score (IPSS), and quality of life score (QoL) in one year of follow-up. Statistical analysis was done using Wilcoxon signed-rank test. Results: At baseline, mean age was 70±9 years and prostate size was 163±62g. Most patients (84%) were in retention and 10 (40%) patients were on anticoagulation. Seven (28%) patients went home the day of surgery (mean hospital stay: 1.2±1.2d). There were 2 intraoperative complications (8%), both cystotomies related to morcellation. Nine patients (36%) experienced a complication, all within 30 days. There were no Clavien ≥III complications. Significant improvements were seen in Qmax, PVR, IPSS, and QoL score at each time interval to 12-months following surgery (all p<0.05). Of 21 patients initially in retention, all were voiding at last follow-up. Conclusions: Our findings suggest that ThuVEP is an effective treatment for BPH in patients with large prostates with sustained results for one year. PMID:27564287

  7. Laser Prostatectomy: Holmium Laser Enucleation and Photoselective Laser Vaporization of the Prostate

    PubMed Central

    Bostanci, Yakup; Kazzazi, Amir; Djavan, Bob

    2013-01-01

    Historically, transurethral resection of the prostate has been the gold standard for the treatment of benign prostatic hyperplasia (BPH). Laser technology has been used to treat BPH for > 15 years. Over the past decade, it has gained wide acceptance by experienced urologists. This review provides an evidence-based update on laser surgery for BPH with a focus on photoselective laser vaporization and holmium laser enucleation of the prostate surgeries and assesses the safety, efficacy, and durability of these techniques. PMID:23671400

  8. Femtosecond laser based enucleation of porcine oocytes for somatic cell nuclear transfer

    NASA Astrophysics Data System (ADS)

    Kütemeyer, K.; Lucas-Hahn, A.; Petersen, B.; Hassel, P.; Lemme, E.; Niemann, H.; Heisterkamp, A.

    2009-07-01

    Cloning of several mammalian species has been achieved by somatic cell nuclear transfer (SCNT) in recent years. However, this method still results in very low efficiencies around 1% which originate from suboptimal culture conditions and highly invasive techniques for oocyte enucleation and injection of the donor cell using micromanipulators. In this paper, we present a new minimal invasive method for oocyte imaging and enucleation based on the application of femtosecond (fs) laser pulses. After imaging of the oocyte with multiphoton microscopy, ultrashort pulses are focused onto the metaphase plate of MII-oocytes in order to ablate the DNA molecules. We show that fs laser based enucleation of porcine oocytes completely inhibits the first mitotic cleavage after parthenogenetic activation while maintaining intact oocyte morphology in most cases. In contrast, control groups without previous irradiation of the metaphase plate are able to develop to the blastocyst stage. Further experiments have to clarify the suitability of fs laser based enucleated oocytes for SCNT.

  9. Combined multiphoton imaging and automated functional enucleation of porcine oocytes using femtosecond laser pulses

    NASA Astrophysics Data System (ADS)

    Kuetemeyer, Kai; Lucas-Hahn, Andrea; Petersen, Bjoern; Lemme, Erika; Hassel, Petra; Niemann, Heiner; Heisterkamp, Alexander

    2010-07-01

    Since the birth of ``Dolly'' as the first mammal cloned from a differentiated cell, somatic cell cloning has been successful in several mammalian species, albeit at low success rates. The highly invasive mechanical enucleation step of a cloning protocol requires sophisticated, expensive equipment and considerable micromanipulation skill. We present a novel noninvasive method for combined oocyte imaging and automated functional enucleation using femtosecond (fs) laser pulses. After three-dimensional imaging of Hoechst-labeled porcine oocytes by multiphoton microscopy, our self-developed software automatically identified the metaphase plate. Subsequent irradiation of the metaphase chromosomes with the very same laser at higher pulse energies in the low-density-plasma regime was used for metaphase plate ablation (functional enucleation). We show that fs laser-based functional enucleation of porcine oocytes completely inhibited the parthenogenetic development without affecting the oocyte morphology. In contrast, nonirradiated oocytes were able to develop parthenogenetically to the blastocyst stage without significant differences to controls. Our results indicate that fs laser systems have great potential for oocyte imaging and functional enucleation and may improve the efficiency of somatic cell cloning.

  10. Holmium laser enucleation of the prostate: a paradigm shift in benign prostatic hyperplasia surgery

    PubMed Central

    2013-01-01

    Holmium laser enucleation (HoLEP) was developed in the 1990s as a more efficient and cost effective method of benign prostatic hyperplasia surgery than laser vaporization and resection techniques. As a true anatomical enucleation it mimics open prostatectomy and is as durable. There is a significant body of level 1 evidence in support of HoLEP, including 2 meta-analyses and 14 randomized trials which compare HoLEP with a number of other procedures. This review describes the development of and summarizes the evidence for HoLEP. PMID:24082919

  11. Holmium laser enucleation of the prostate: a paradigm shift in benign prostatic hyperplasia surgery.

    PubMed

    Aho, Tevita F

    2013-10-01

    Holmium laser enucleation (HoLEP) was developed in the 1990s as a more efficient and cost effective method of benign prostatic hyperplasia surgery than laser vaporization and resection techniques. As a true anatomical enucleation it mimics open prostatectomy and is as durable. There is a significant body of level 1 evidence in support of HoLEP, including 2 meta-analyses and 14 randomized trials which compare HoLEP with a number of other procedures. This review describes the development of and summarizes the evidence for HoLEP. PMID:24082919

  12. Office Hysteroscopic Laser Enucleation of Submucous Myomas without Mass Extraction: A Case Series Study

    PubMed Central

    Haimovich, Sergio; López-Yarto, Maite; Urresta Ávila, Julio; Saavedra Tascón, Alejandro; Hernández, José L.; Carreras Collado, Ramón

    2015-01-01

    Background and Objectives. A new two-step hysteroscopic myomectomy carried out in the office setting and without anesthesia was feasible for the excision of submucous myomas. The objective of this study was to assess whether removal of submucous myomas from the uterine cavity after hysteroscopic laser enucleation is necessary. Methods. Between June 2009 and April 2013, all outpatients with symptomatic myomatosis (bleeding, pelvic pain, and infertility) assessed ultrasonographically were eligible to participate in a prospective study. All patients underwent office hysteroscopic enucleation of submucous myomas. Enucleated myomas were left in the uterine cavity. Neither anesthesia nor antibiotic prophylaxis was used. Results. Sixty-one women (mean age: 47.3 years) were included. Regardless of hysteroscopic localization and grading, all myomas were enucleated. The mean (standard deviation, SD) diameter of the myoma as measured by the ultrasound scan was 22.6 (8.5) mm. In 29 cases (47.5%), the diameter of the resected myoma was >20 mm and in 10 cases (16.4%) >30 mm. After a mean follow-up of 68.2 (16.5) days, none of the patients showed a residual myoma inside the uterine cavity. Conclusions. The present results indicate that leaving laser-enucleated submucous myoma in the uterine cavity is a feasible and safe therapeutic option. PMID:26090457

  13. Bipolar, Monopolar, Photovaporization of the Prostate, or Holmium Laser Enucleation of the Prostate: How to Choose What's Best?

    PubMed

    Cornu, Jean-Nicolas

    2016-08-01

    Endoscopic management of benign prostatic obstruction is based on resection, vaporization, or enucleation. Enucleation provides the best efficacy and long-term outcome. Lasers have advantages in patients at high risk of bleeding. Holmium enucleation is the best evaluated technique, but has a steep learning curve. Greenlight photovaporization is a safe alternative to transurethral resection of the prostate (TURP) in prostates of less than 100 mL, especially in patients at high risk of bleeding. Bipolar devices can be used for resection, vaporization, and enucleation and provides efficacy results similar to TURP in the short term with better safety. PMID:27476130

  14. Functional enucleation of porcine oocytes for somatic cell nuclear transfer using femtosecond laser pulses

    NASA Astrophysics Data System (ADS)

    Kuetemeyer, K.; Lucas-Hahn, A.; Petersen, B.; Hassel, P.; Lemme, E.; Niemann, H.; Heisterkamp, A.

    2010-02-01

    Cloning of several mammalian species has been achieved by somatic cell nuclear transfer over the last decade. However, this method still results in very low efficiencies originating from biological and technical aspects. The highly-invasive mechanical enucleation belongs to the technical aspects and requires considerable micromanipulation skill. In this paper, we present a novel non-invasive method for combined oocyte imaging and automated functional enucleation using femtosecond (fs) laser pulses. After three-dimensional imaging of Hoechst-labeled porcine oocytes by multiphoton microscopy, our self-developed software automatically determined the metaphase plate position and shape. Subsequent irradiation of this volume with the very same laser at higher pulse energies in the low-density-plasma regime was used for metaphase plate ablation. We show that functional fs laser-based enucleation of porcine oocytes completely inhibited further embryonic development while maintaining intact oocyte morphology. In contrast, non-irradiated oocytes were able to develop to the blastocyst stage without significant differences to control oocytes. Our results indicate that fs laser systems offer great potential for oocyte imaging and enucleation as a fast, easy to use and reliable tool which may improve the efficiency of somatic cell clone production.

  15. Holmium laser enucleation of the prostate: a review of the clinical trial evidence.

    PubMed

    Cynk, Mark

    2014-04-01

    Transurethral resection of the prostate (TURP) has remained the procedure of choice for the surgical treatment of bladder outflow obstruction for almost five decades, but holmium laser enucleation of the prostate (HoLEP) is now emerging as a challenger as the gold standard procedure. This review summarizes the evidence base for HoLEP, with particular reference to randomized, controlled (level 1) evidence. PMID:24688602

  16. Holmium laser enucleation of the prostate: a review of the clinical trial evidence

    PubMed Central

    2014-01-01

    Transurethral resection of the prostate (TURP) has remained the procedure of choice for the surgical treatment of bladder outflow obstruction for almost five decades, but holmium laser enucleation of the prostate (HoLEP) is now emerging as a challenger as the gold standard procedure. This review summarizes the evidence base for HoLEP, with particular reference to randomized, controlled (level 1) evidence. PMID:24688602

  17. Holmium Laser Enucleation of the Prostate and Iatrogenic Arteriovenous Fistula Treated by Superselective Arterial Embolization.

    PubMed

    Asimakopoulos, Anastasios D; Dutto, Lorenzo; Preziosi, Paolo; Spera, Enrico; Micali, Francesco; De Carolis, Andrea; Iorio, Beniamino

    2016-01-01

    Iatrogenic pelvic pseudoaneurysm with concomitant arteriovenous fistula has been described as a rare and challenging complication, which may occur during transurethral resection of the prostate. We provide the first report of this complication after holmium laser enucleation of the prostate for the treatment of benign prostatic hyperplasia. The attempt to control the bleeding by conversion to open surgery and placement of haemostatic stitches into the prostatic fossa failed. Angiography with superselective arterial embolization proved to be a modern, quick, safe, and efficient treatment of this uncommon complication. PMID:27022498

  18. Holmium Laser Enucleation of the Prostate and Iatrogenic Arteriovenous Fistula Treated by Superselective Arterial Embolization

    PubMed Central

    Dutto, Lorenzo; Preziosi, Paolo; Spera, Enrico; Micali, Francesco; De Carolis, Andrea; Iorio, Beniamino

    2016-01-01

    Iatrogenic pelvic pseudoaneurysm with concomitant arteriovenous fistula has been described as a rare and challenging complication, which may occur during transurethral resection of the prostate. We provide the first report of this complication after holmium laser enucleation of the prostate for the treatment of benign prostatic hyperplasia. The attempt to control the bleeding by conversion to open surgery and placement of haemostatic stitches into the prostatic fossa failed. Angiography with superselective arterial embolization proved to be a modern, quick, safe, and efficient treatment of this uncommon complication. PMID:27022498

  19. Technical Aspects of Holmium Laser Enucleation of the Prostate for Benign Prostatic Hyperplasia

    PubMed Central

    Kim, Myong; Lee, Hahn-Ey

    2013-01-01

    Holmium laser enucleation of the prostate (HoLEP) is a minimally invasive procedure and a size-independent treatment for benign prostatic hyperplasia with excellent long-term surgical outcome. HoLEP has become an alternative to conventional transurethral resection of the prostate or open prostatectomy owing to its efficacy and safety. Although HoLEP is known to have a steep learning curve, very few articles have addressed the technical aspects of HoLEP. Herein, we described detailed techniques and tips for HoLEP as performed at Seoul National University Hospital in a step-by-step manner with extensive review of the literature. PMID:24044089

  20. Technical aspects of holmium laser enucleation of the prostate for benign prostatic hyperplasia.

    PubMed

    Kim, Myong; Lee, Hahn-Ey; Oh, Seung-June

    2013-09-01

    Holmium laser enucleation of the prostate (HoLEP) is a minimally invasive procedure and a size-independent treatment for benign prostatic hyperplasia with excellent long-term surgical outcome. HoLEP has become an alternative to conventional transurethral resection of the prostate or open prostatectomy owing to its efficacy and safety. Although HoLEP is known to have a steep learning curve, very few articles have addressed the technical aspects of HoLEP. Herein, we described detailed techniques and tips for HoLEP as performed at Seoul National University Hospital in a step-by-step manner with extensive review of the literature. PMID:24044089

  1. Acute abdominal compartment syndrome as a complication of Holmium laser enucleation of the prostate: a case report

    PubMed Central

    2014-01-01

    Background In 1996, Holmium laser enucleation of the prostate was introduced and has been shown to be safe and highly effective. Case presentation We report a case of a rare complication that resulted in intra-abdominal compartment syndrome with prolonged intubation and intensive care, involving an 74-year-old male after holmium laser enucleation of prostate, with a massive irrigant fluid leakage into the retroperitoneal space. The elevated abdominal pressure was reduced by forced diuresis. The tracheal tube was removed 18 hours after the patient’s transfer to the ICU. The patient was discharged to home one week after the operation. Conclusion In rare cases when no obvious ruptures of the prostate capsule or the bladder occur during laser enucleation of prostate, knowledge regarding possible emersion of massive amounts of irrigant fluid into the retroperitoneal space leading to intra-abdominal compartment syndrome aids in the diagnosis and subsequent successful therapy of intra-abdominal hypertension. PMID:24910537

  2. Evidence of the efficacy and safety of the thulium laser in the treatment of men with benign prostatic obstruction

    PubMed Central

    Barbalat, Yana; Velez, Marissa C.; Sayegh, Christopher I.; Chung, Doreen E.

    2016-01-01

    In 2005, the high power thulium laser was introduced for the surgical treatment of benign prostatic obstruction. It has several properties that confer theoretical advantages over other lasers used for the same indication, such as technical versatility and a relatively small zone of thermal damage. Studies using the 70–150 W thulium laser systems demonstrate good efficacy of these procedures with low morbidity and few complications even in higher risk patients. Different techniques have been employed to treat the prostate with this technology, including enucleation, vapoenucleation, vaporization and resection. Comparative studies have been published comparing thulium laser prostatectomy to monopolar transurethral resection of prostate (TURP), bipolar TURP and holmium laser enucleation of prostate (HoLEP). In this review we discuss the current literature on the safety and efficacy of various thulium techniques for the treatment of benign prostatic hyperplasia and examine comparative studies. PMID:27247628

  3. Evidence of the efficacy and safety of the thulium laser in the treatment of men with benign prostatic obstruction.

    PubMed

    Barbalat, Yana; Velez, Marissa C; Sayegh, Christopher I; Chung, Doreen E

    2016-06-01

    In 2005, the high power thulium laser was introduced for the surgical treatment of benign prostatic obstruction. It has several properties that confer theoretical advantages over other lasers used for the same indication, such as technical versatility and a relatively small zone of thermal damage. Studies using the 70-150 W thulium laser systems demonstrate good efficacy of these procedures with low morbidity and few complications even in higher risk patients. Different techniques have been employed to treat the prostate with this technology, including enucleation, vapoenucleation, vaporization and resection. Comparative studies have been published comparing thulium laser prostatectomy to monopolar transurethral resection of prostate (TURP), bipolar TURP and holmium laser enucleation of prostate (HoLEP). In this review we discuss the current literature on the safety and efficacy of various thulium techniques for the treatment of benign prostatic hyperplasia and examine comparative studies. PMID:27247628

  4. A novel one lobe technique of thulium laser enucleation of the prostate: 'All-in-One' technique

    PubMed Central

    Kim, Yeon Joo; Lee, Yoon Hyung; Kwon, Joon Beom; Cho, Sung Ryong

    2015-01-01

    Purpose The thulium laser is the most recently introduced technology for the surgical treatment of benign prostatic hyperplasia (BPH). Until recently, most thulium laser enucleation of the prostate (ThuLEP) was performed by use of the three-lobe technique. We introduce a novel one-lobe enucleation technique for ThuLEP called the "All-in-One" technique. We report our initial experiences here. Materials and Methods From June 2013 to May 2014, a total of 47 patients underwent the All-in-One technique of ThuLEP for symptomatic BPH performed by a single surgeon. All patients were assessed with the International Prostate Symptom Score (IPSS), transrectal ultrasonography, serum prostate-specific antigen (PSA), maximal urine flow rate (Qmax), and postvoid residual urine volume (PVR) before and 1 month after surgery. We reassessed IPSS, Qmax, and PVR 3 months after surgery. To assess the efficacy of the All-in-One technique, we checked the PSA reduction ratio, transitional zone volume reduction ratio, and enucleation failure rate. Results The mean operative time was 82.1±33.3 minutes. The mean enucleation time and morcellation time were 52.7±21.7 minutes and 8.2±7.0 minutes, respectively. The mean resected tissue weight and decrease in hemoglobin were 36.9±24.6 g and 0.4±0.8 g/dL, respectively. All perioperative parameters showed significant improvement (p<0.05). No major complications were observed. The PSA reduction ratio, transitional zone volume reduction ratio, and enucleation failure rate were 0.81, 0.92, and 4.3%, respectively. Conclusions The All-in-One technique of ThuLEP showed efficacy and effectiveness comparable to that of other techniques. We expect that this new technique could reduce the operation time and the bleeding and improve the effectiveness of enucleation. PMID:26568795

  5. Holmium Laser Enucleation of the Prostate in a 400 cc Prostate: Case Report.

    PubMed

    Gopee, Esha L; Hong, Matthew K H; Pham, Trung

    2016-01-01

    The modality of choice in the surgical management of benign prostatic hyperplasia for large prostates has traditionally been open prostatectomy. Advances in minimally invasive techniques have begun to challenge this notion with advantages such as lower bleeding and transfusion rates and shorter hospital stay. In this case report, we illustrate the use of holmium laser enucleation of the prostate (HoLEP) in a gland measuring more than 400 cc. We describe the case of a 71-year-old man with persistent voiding urinary symptoms despite two previous transurethral resections of his prostate. With greater experience in HoLEP and declining experience in open prostatectomy, there may be a shift toward HoLEP as the preferred treatment choice for large prostate glands. PMID:27579406

  6. Holmium Laser Enucleation of the Prostate in a 400 cc Prostate: Case Report

    PubMed Central

    Hong, Matthew K.H.; Pham, Trung

    2016-01-01

    Abstract The modality of choice in the surgical management of benign prostatic hyperplasia for large prostates has traditionally been open prostatectomy. Advances in minimally invasive techniques have begun to challenge this notion with advantages such as lower bleeding and transfusion rates and shorter hospital stay. In this case report, we illustrate the use of holmium laser enucleation of the prostate (HoLEP) in a gland measuring more than 400 cc. We describe the case of a 71-year-old man with persistent voiding urinary symptoms despite two previous transurethral resections of his prostate. With greater experience in HoLEP and declining experience in open prostatectomy, there may be a shift toward HoLEP as the preferred treatment choice for large prostate glands. PMID:27579406

  7. Holmium Laser Enucleation of the Prostate is Safe for Patients Above 80 Years: A Prospective Study

    PubMed Central

    2016-01-01

    Purpose: To evaluate the effect of age on the efficacy and safety of holmium laser enucleation of the prostate (HoLEP) for the treatment of symptomatic benign prostatic hyperplasia (BPH). Methods: A total of 579 patients underwent HoLEP procedure performed by a single surgeon (SJO) between December 2009 and May 2013. The perioperative and functional outcomes of patients in the age groups of 50–59 (group A, n=44), 60–69 (group B, n=253), 70–79 (group C, n=244), and ≥80 years (group D, n=38) were compared. The Clavien-Dindo system was used to evaluate clinical outcomes. The International Prostate Symptom Score (IPSS), maximum urinary flow rate (Qmax), postvoid residual (PVR) urine volume, and urinary continence were used to assess functional outcomes. Results: In this study, the patients ≥80 years had significantly higher presence of hypertension (P=0.007), total prostate volumes (P=0.024), transitional zone volume (P=0.002), American Society of Anesthesiologists scores (P=0.006), urinary retention (P=0.032), and anticoagulation use (P=0.008) at preoperative period. Moreover, the mean values of operation time, enucleation time, morcellation time, and enucleation weight were higher in group D compared with other group patients (P=0.002, P=0.010, P<0.01, and P=0.009, respectively). Patients aged ≥80 years had a longer hospital stay time (2.9±1.8 days) than other groups (group A, 2.3±0.7 days; group B, 2.3±0.7 days vs. group C, 2.4±0.7 days; P=0.001). All groups were similar in regard to the incidence of complications (Clavien-Dindo grade) post operatively (P>0.05). All the patients in the present study showed improvement in functional outcomes after HoLEP. By the sixth month, there were no significant differences in IPSS, quality of life, Qmax, and PVR among the groups (P>0.05). Conclusions: Compared with younger patients, the patients aged ≥80 years had a similar overall morbidity and 6-month functional outcomes of HoLEP. HoLEP is a safe and

  8. Holmium Laser Enucleation of Prostate for Benign Prostatic Hyperplasia: Seoul National University Hospital Experience

    PubMed Central

    Bae, Jungbum; Choo, Minsoo; Park, Ji Hyun; Oh, Jin Kyu; Paick, Jae-Seung

    2011-01-01

    Purpose The objective of this study was to report the experience acquired at the Seoul National University Hospital with Holmium Laser Enucleation of Prostate (HoLEP), combined with mechanical morcellation for symptomatic benign prostatic hyperplasia (BPH). Methods A retrospective review was performed on the clinical data of 309 consecutive patients who underwent HoLEP at our institution between July 2008 and June 2010. All patients were evaluated preoperatively for prostate volume by transrectal ultrasound, maximum urinary flow rate (Qmax), International Prostate Symptoms Score (IPSS) and quality of life (QoL) score. Peri- and postoperative parameters were evaluated and patients were followed-up at 1-, 3-, 6-, and 12- months with the aforementioned investigations. Results The patients' mean age was 68.3 (±6.5) years and mean prostate volume was 55.6 (±23.6) mL. Mean enucleation time was 56.2 (±25.1) minutes, mean morcellation time was 11.3 (±9.5) minutes, and the mean resected weight of the prostate was 20.8 (±16.9) g. The mean catheter indwelling period was 1.9 (±1.7) days and mean hospital stay was 2.9 (±1.5) days. Significant improvement was noted in Qmax, IPSS, and QoL at the 1-year follow-up compared with baseline (P<0.01). At 1 month 17.2% of patients complained of irritative urinary symptoms, which were typically self-limiting within 3 months. Transient stress incontinence was reported in 15.2% of patients. No patient experienced persistent obstructive symptoms that required reoperation. Conclusions Our study showed that HoLEP is a safe and effective therapeutic modality for BPH. PMID:21468284

  9. Salvage Holmium laser enucleation of prostate to treat residual benign prostatic hyperplasia

    PubMed Central

    Oh, Jin Kyu; Bae, Jungbum; Jeong, Chang Wook; Paick, Jae-Seung; Oh, Seung-June

    2014-01-01

    Introduction: The Holmium laser enucleation of the prostate (HoLEP) technique to remove residual adenoma has not been reported. Salvage HoLEP enables anatomical enucleation of residual adenoma in patients who have previously undergone surgical treatment. We describe not only anatomical insights into the frequent location of adenoma recurrence, but also the feasibility of the salvage HoLEP technique. Methods: We retrospectively reviewed a database containing HoLEP video records for 35 patients out of a total of 535 individuals on whom HoLEP was performed by 2 surgeons (SJO & JSP) between July 2008 and June 2011. Group 1 consisted of patients who underwent salvage HoLEP due to recurring adenoma and Group 2 of patients who underwent HoLEP as an initially surgical management to treat benign prostate hyperplasia (BPH). We compared the dataset of pre-, intra- and postoperative parameters between Groups 1 and 2. Results: In the analysis of the video records of Group 1 (n = 35), there was significant remnant tissue around the verumontanum and the lateral lobes were also incompletely removed by previous conventional procedures. When we compared pre-, intra- and postoperative parameters between the 2 groups, there were no significant differences, including operation time, duration of hospital stay. However, the duration of the catheterization of Group 1 was shorter than that of Group 2 (1.38 ± 0.55 vs. 1.90 ± 1.81 days, p < 0.001). Conclusions: Even for cases of residual BPH, salvage HoLEP is a feasible and effective procedure for treating residual adenoma along the anatomical plane. PMID:24839489

  10. Predictive risk factors of postoperative urinary incontinence following holmium laser enucleation of the prostate during the initial learning period

    PubMed Central

    Kobayashi, Shuichiro; Yano, Masataka; Nakayama, Takayuki; Kitahara, Satoshi

    2016-01-01

    ABSTRACT Purpose: To determine the predictive factors for postoperative urinary incontinence (UI) following holmium laser enucleation of the prostate (HoLEP) during the initial learning period. Patients and Methods: We evaluated 127 patients with benign prostatic hyperplasia who underwent HoLEP between January 2011 and December 2013. We recorded clinical variables, including blood loss, serum prostate-specific antigen levels, and the presence or absence of UI. Blood loss was estimated as a decline in postoperative hemoglobin levels. The predictive factors for postoperative UI were determined using a multivariable logistic regression analysis. Results: Postoperative UI occurred in 31 patients (24.4%), but it cured in 29 patients (93.5%) after a mean duration of 12 weeks. Enucleation time >100 min (p=0.043) and blood loss >2.5g/dL (p=0.032) were identified as significant and independent risk factors for postoperative UI. Conclusions: Longer enucleation time and increased blood loss were independent predictors of postoperative UI in patients who underwent HoLEP during the initial learning period. Surgeons in training should take care to perform speedy enucleation maneuver with hemostasis. PMID:27564285

  11. Clinical and Pathological Characteristics of Hard Nodules Resistant to Morcellation During Holmium Laser Enucleation of the Prostate

    PubMed Central

    Piao, Songzhe; Choo, Min Soo; Wang, Yue; Lee, Young Ju; Bae, Jungbum; Oh, Seung-June

    2015-01-01

    Purpose: To identify the clinical and pathological characteristics of hard nodules resistant to morcellation (HNRM) during holmium laser enucleation of the prostate (HoLEP) for benign prostatic hyperplasia (BPH). Methods: Between July 2008 and October 2011, 246 patients underwent HoLEP for symptomatic BPH. The first 30 patients were excluded from the analysis due to the learning curve of the procedure. The remaining patients were divided into HNRM (n=29) and non-HNRM groups (n=187), and comparative analysis of the clinical parameters of the two groups was performed. International prostate symptom score analysis and urodynamic studies were performed preoperatively. Histological analysis was performed after hematoxylin and eosin staining and Masson trichrome staining of the HNRM specimens. Results: Twenty-nine patients (13.4%) had HNRM. The patients in the HNRM group had significantly higher proportions of advanced age (≥65 years, P=0.029), total prostate volume ≥65 mL (P<0.001), transition zone volume ≥35 mL (P<0.001), serum prostate-specific antigen levels ≥10 ng/mL (P=0.007), and functional urethral length ≥70 mm (P=0.009); larger enucleation weight (P<0.001); longer operation (P=0.001), enucleation (P=0.042), and morcellation times (P<0.001); and higher enucleation ratio (P=0.028) and enucleation efficacy (P=0.001). After adjusting for confounding factors, multivariate logistic regression analysis revealed that age ≥65 years and total prostate volume ≥65 mL were independent risk factors for HNRM. Pathological examination did not reveal any malignant cells, with mainly dense fibrous tissue found in the HNRM. Conclusions: HNRM can make morcellation cumbersome and time-consuming, and older patients with larger prostates have a higher incidence of HNRM. However, the histopathology of HNRM revealed mainly fibrotic tissue. PMID:26126438

  12. Benign Prostatic Hyperplasia Treatment by Transurethral Enucleation of the Prostate Using a 2-μm Laser.

    PubMed

    Guo, He-Qing; Zhou, Gao-Biao; Liu, Hong-Ming; Sun, Bin; Pan, Guang-Xin; Mu, Da-Wei; Yan, Jing-Ming; Xing, Ji-Zhang; Li, Di; Hong, Quan

    2015-12-01

    This study investigates the efficacy of benign prostatic hyperplasia (BPH) treatment by prostate transurethral enucleation using a 2-μm laser. A total of 107 patients with BPH were treated by prostate transurethral enucleation using a RevoLix 2-μm laser surgery system. Bleeding volume, operation time, catheterization time, voiding situation, maximum urinary flow rate, and hospital stay were observed. The mean operation time was 74 min ± 12 min (range 45 to 150 min), the mean follow-up period was 2 to 6 months, the mean catheter time was 5 days, and the mean peak urinary flow rate increased from 6.3 ± 0.6 to 17.5 ± 1.5 mL/s. The International Prostate Symptom Score and quality of life significantly declined (p < 0.01). No significant differences were observed in the hemoglobin and blood electrolytes before and after operation. Prostate transurethral enucleation using a 2-μm laser is safe and efficient for BPH treatment. PMID:27011513

  13. An Improved Morcellation Procedure for Holmium Laser Enucleation of the Prostate

    PubMed Central

    Chen, Qi; Chen, Yan-Bo; Zheng, Da-Chao; Cai, Zhi-Kang; Li, Wen-Ji; Zhou, Juan

    2012-01-01

    Abstract Purpose We modified the conventional morcellation procedure for holmium laser enucleation of the prostate (HoLEP), and its outcomes are presented in this article. Materials and Methods As 395 patients were included, the conventional morcellation procedure was performed in the first 100 cases (group 1, cases 1–100), and an improved procedure was used in the last 100 cases (group 2, cases 296–395). The improved morcellation process has three steps to execute. The morcellation time, collected tissue weight, morcellation rate, and associated complications were recorded. Results The tissue-resected weight was similar between group 1 (60.7±33.9 g) and group 2 (62.4±36.8 g). The mean morcellation time in group 1 was greater than that in group 2 (11.3±7.1 and 8.3±4.1 minutes, respectively), and the mean morcellation rate was better in group 2 than in group 1 (5.75±1.7 g/minutes in group 1 v 7.3±1.1 g/minutes in group 2). Complications, such as bladder injury, were similar in both groups. Conclusion The improved morcellation procedure described in this article can be used in various situations of suction and can be performed in a more fluent manner and with better efficiency. PMID:22788738

  14. Efficacy of Holmium Laser Enucleation of the Prostate Based on Patient Preoperative Characteristics

    PubMed Central

    Suh, Yoon Seok; Kim, Tae Heon; Sung, Hyun Hwan; Jeong, Jeongyun

    2015-01-01

    Purpose: To evaluate the efficacy of holmium laser enucleation of the prostate (HoLEP) in relation to prostate size and urodynamic parameters, including bladder outlet obstruction index (BOOI), presence of detrusor overactivity, and detrusor contractility, and to investigate factors predictive of HoLEP success. Methods: This retrospective analysis of prospective data included 174 consecutive patients treated with HoLEP at Samsung Medical Center from 2009 to 2013. Prostate-specific antigen, prostate size, urodynamic parameters, and International Prostate Symptom Score (IPSS)/quality of life (QoL) were evaluated preoperatively, while prostate-specific antigen, uroflowmetry/postvoid residual (PVR) urine, and IPSS were measured six months after HoLEP. Two definitions of treatment success were established based on the following three variables: IPSS, maximum flow rate (Qmax), and QoL index. Factors predictive of HoLEP success were identified using multiple logistic regression analysis. Results: IPSS/QoL, Qmax, and PVR improved significantly following HoLEP. Improvements in IPSS and PVR were more significant in the BOOI≥40 group compared to the BOOI<40 group, with overall success rates of 93.7% and 73.6%, respectively. Thus, the BOOI≥40 group had a significantly higher success rate, and BOOI≥40 was a significant predictor of HoLEP success based on the multivariate analyses. Conclusions: We found good surgical outcomes after HoLEP, and specifically patients with a higher BOOI had a greater chance of surgical success. PMID:26739183

  15. Sexual outcome of patients undergoing thulium laser enucleation of the prostate for benign prostatic hyperplasia.

    PubMed

    Carmignani, Luca; Bozzini, Giorgio; Macchi, Alberto; Maruccia, Serena; Picozzi, Stefano; Casellato, Stefano

    2015-01-01

    Treatment of patients with lower urinary tract symptoms (LUTS) secondary to benign prostatic hyperplasia (BPH) may affect the quality of sexual function and ejaculation. The effect of new surgical procedures, which are currently available to treat BPH, on erection and ejaculation, has been poorly studied. This study aimed to assess the effect of thulium laser enucleation of the prostate (ThuLEP) on sexual function and retrograde ejaculation in patients with LUTS secondary to BPH. We performed a prospective study in 110 consecutive patients who had undergone ThuLEP to analyze changes in sexual function and urinary symptoms. To evaluate changes in erection and ejaculation, and the effect of urinary symptoms on the quality of life (QoL), five validated questionnaires were used: the ICIQ-MLUTSsex, MSHQ-EjD, International Index of Erectile Function 5, International Prognostic Scoring System (IPSS) questionnaire, and QoL index of the intraclass correlation coefficients. Patients also underwent IPSS and flowmetry to assess the outcome of flow. Patients were evaluated before surgery and 3-6 months after ThuLEP, whereas those with previous abdominal surgery were excluded. The patients' mean age was 67.83 years. Postoperative urinary symptoms improved after surgery. No significant differences in erectile function before and after surgery were observed. As compared with other techniques described in the literature, the percentage of patients with conserved ejaculation increased by 52.7% after ThuLEP. ThuLEP positively affects urinary symptoms and their effect on the QoL of patients as assessed by questionnaire scores. While endoscopic management of BPH (e.g. transurethral resection of the prostate) causes retrograde ejaculation in most patients, those who undergo ThuLEP have conserved ejaculation and erectile function. PMID:25652616

  16. Risk Factors for Transient Urinary Incontinence after Holmium Laser Enucleation of the Prostate

    PubMed Central

    Nam, Jong Kil; Kim, Hyeon Woo; Lee, Dong Hoon; Han, Ji-Yeon; Lee, Jeong Zoo

    2015-01-01

    Purpose To investigate the factors associated with the occurrence of and recovery from transient urinary incontinence (TUI) after holmium laser enucleation of the prostate (HoLEP). Materials and Methods From March 2009 to December 2012, 391 consecutive patients treated with HoLEP for benign prostatic hyperplasia were enrolled. Information regarding age, prostate volume, International Prostate Symptom Score, Overactive Bladder Symptom Score, peak urinary flow rate, postvoid residual urine, and operation time was collected. TUI was defined as a patient complaint of urine leakage, regardless of type. Logistic regression was used to investigate the factors associated with the occurrence of TUI, and the Kaplan-Meier test was used to analyze the TUI recovery period. Results TUI after HoLEP occurred in 65 patients (16.6%), 52 patients of whom (80.0%) showed recovery within three months. Stress and urge urinary incontinence and postvoid dribbling occurred in 16 patients (4.1%), 29 patients (7.4%), and 33 patients (8.4%), respectively. Age (odds ratio [OR]=3.494; 95% confidence interval [CI]=1.565~7.803; p=0.002) and total operation time (OR=3.849; 95% CI=1.613~9.185; p=0.002) were factors that significantly affected the occurrence of TUI. Conclusions TUI, defined as any type of urine leakage, occurred after HoLEP in some patients, most of whom recovered within three months. Stress urinary incontinence occurred in only 4% of patients after HoLEP. Age and total operation time were associated with the occurrence of postoperative TUI. PMID:26331125

  17. Sexual outcome of patients undergoing thulium laser enucleation of the prostate for benign prostatic hyperplasia

    PubMed Central

    Carmignani, Luca; Bozzini, Giorgio; Macchi, Alberto; Maruccia, Serena; Picozzi, Stefano; Casellato, Stefano

    2015-01-01

    Treatment of patients with lower urinary tract symptoms (LUTS) secondary to benign prostatic hyperplasia (BPH) may affect the quality of sexual function and ejaculation. The effect of new surgical procedures, which are currently available to treat BPH, on erection and ejaculation, has been poorly studied. This study aimed to assess the effect of thulium laser enucleation of the prostate (ThuLEP) on sexual function and retrograde ejaculation in patients with LUTS secondary to BPH. We performed a prospective study in 110 consecutive patients who had undergone ThuLEP to analyze changes in sexual function and urinary symptoms. To evaluate changes in erection and ejaculation, and the effect of urinary symptoms on the quality of life (QoL), five validated questionnaires were used: the ICIQ-MLUTSsex, MSHQ-EjD, International Index of Erectile Function 5, International Prognostic Scoring System (IPSS) questionnaire, and QoL index of the intraclass correlation coefficients. Patients also underwent IPSS and flowmetry to assess the outcome of flow. Patients were evaluated before surgery and 3–6 months after ThuLEP, whereas those with previous abdominal surgery were excluded. The patients’ mean age was 67.83 years. Postoperative urinary symptoms improved after surgery. No significant differences in erectile function before and after surgery were observed. As compared with other techniques described in the literature, the percentage of patients with conserved ejaculation increased by 52.7% after ThuLEP. ThuLEP positively affects urinary symptoms and their effect on the QoL of patients as assessed by questionnaire scores. While endoscopic management of BPH (e.g. transurethral resection of the prostate) causes retrograde ejaculation in most patients, those who undergo ThuLEP have conserved ejaculation and erectile function. PMID:25652616

  18. Transurethral Surgical Anatomy of the Arterial Bleeder in the Enucleated Capsular Plane of Enlarged Prostates During Holmium Laser Enucleation of the Prostate

    PubMed Central

    Choo, Min Soo; Lee, Hahn-Ey; Bae, Jungbum; Cho, Sung Yong

    2014-01-01

    Purpose To identify the endoscopic vascular anatomy of the prostate during Holmium laser enucleation of the prostate (HoLEP), and analyze the clinical risk factors associated with significant arterial bleeding. Methods We identified 107 consecutive patients with benign prostatic hyperplasia who underwent HoLEP between September 2009 and August 2010, performed by a single surgeon (S.J.O.). Two independent reviewers reviewed the surgery video database and completed a prespecified form. The location of bleeding arteries was marked at the level of the bladder neck, proximal prostate, distal prostate, and verumontanum. Arterial bleeding was classified into one of three grades according to bleeding severity (grades 2 and 3 indicate significant bleeding). Results The mean prostate volume was 65.1±31.5 mL, and the mean prostate-specific antigen (PSA) level was 3.69±3.58 ng/mL. During the HoLEP procedure, the most common locations of significant bleeders were the 2-5 and 7-10 o'clock positions in the proximal prostate. The average number of bleeding arteries was 12.1±7.9 per procedure, and 1.93±1.20 per 10 mL of prostate volume. Multivariate analysis revealed that prostate volume and serum PSA were significant parameters for estimating the number of bleeding vessels. Conclusions During the HoLEP procedure, the most common locations of significant bleeders were the 2-5 and 7-10 o'clock positions in the proximal prostate. Prostate volume was associated with the number of bleeders. A careful approach to the capsular plane of the proximal prostate facilitates early hemostasis during the HoLEP procedure, especially with larger adenomas. PMID:25279241

  19. The Impact of Increased Bladder Blood Flow on Storage Symptoms after Holmium Laser Enucleation of the Prostate.

    PubMed

    Saito, Keisuke; Hisasue, Shin-ichi; Ide, Hisamitsu; Aoki, Hiroaki; Muto, Satoru; Yamaguchi, Raizo; Tsujimura, Akira; Horie, Shigeo

    2015-01-01

    In order to investigate how holmium laser enucleation of the prostate (HoLEP) improves urinary storage symptoms, we assessed blood flow in the urinary bladder mucosa of patients with benign prostatic hyperplasia (BPH) before and after laser surgery. Seventy-four consecutive patients with BPH (median age 69 years, range; 53-88) underwent HoLEP at our institution and are included in this study. We prospectively assessed the International Prostate Symptom Score (IPSS), IPSS-QOL Score, the Overactive Bladder Symptom Score (OABSS), uroflowmetry, and blood flow in the urinary bladder, before and after surgery. Blood flow in the bladder mucosa was measured using the OMEGA FLOW (OMEGAWAVE, Tokyo, Japan) laser Doppler flowmeter. The median volume of the enucleated adenomas was 45.0 g (range: 25.0 to 83.2). The median IPSS improved significantly from 20 (range: 6-35) to 3 (0-22) (p < 0.001; Wilcoxon signed-rank test), as did the storage symptoms score, which decreased from 13 (2-20) to 3 (1-8) (p < 0.001). Median bladder blood flow increased at the trigone from 9.57 ± 0.83 ml/sec to 17.60 ± 1.08 ml/sec. Multiple regression analysis for the improved storage symptom score eliminated all explanatory variables except increased bladder perfusion. The data suggest that HoLEP improves blood flow in the bladder mucosa, which independently leads to the improvement of storage symptoms. PMID:26090819

  20. The Impact of Increased Bladder Blood Flow on Storage Symptoms after Holmium Laser Enucleation of the Prostate

    PubMed Central

    Ide, Hisamitsu; Aoki, Hiroaki; Muto, Satoru; Yamaguchi, Raizo; Tsujimura, Akira; Horie, Shigeo

    2015-01-01

    In order to investigate how holmium laser enucleation of the prostate (HoLEP) improves urinary storage symptoms, we assessed blood flow in the urinary bladder mucosa of patients with benign prostatic hyperplasia (BPH) before and after laser surgery. Seventy-four consecutive patients with BPH (median age 69 years, range; 53–88) underwent HoLEP at our institution and are included in this study. We prospectively assessed the International Prostate Symptom Score (IPSS), IPSS-QOL Score, the Overactive Bladder Symptom Score (OABSS), uroflowmetry, and blood flow in the urinary bladder, before and after surgery. Blood flow in the bladder mucosa was measured using the OMEGA FLOW (OMEGAWAVE, Tokyo, Japan) laser Doppler flowmeter. The median volume of the enucleated adenomas was 45.0 g (range: 25.0 to 83.2). The median IPSS improved significantly from 20 (range: 6–35) to 3 (0–22) (p<0.001; Wilcoxon signed-rank test), as did the storage symptoms score, which decreased from 13 (2–20) to 3 (1–8) (p<0.001). Median bladder blood flow increased at the trigone from 9.57±0.83 ml/sec to 17.60±1.08 ml/sec. Multiple regression analysis for the improved storage symptom score eliminated all explanatory variables except increased bladder perfusion. The data suggest that HoLEP improves blood flow in the bladder mucosa, which independently leads to the improvement of storage symptoms. PMID:26090819

  1. Factors Affecting De Novo Urinary Retention after Holmium Laser Enucleation of the Prostate

    PubMed Central

    Kim, Sung Han; Yoo, Changwon; Choo, Minsoo; Paick, Jae-Seung; Oh, Seung-June

    2014-01-01

    Objective Patients can experience urinary retention (UR) after Holmium laser enucleation of the prostate (HoLEP) that requires bladder distension during the procedure. The aim of this retrospective study is to identify factors affecting the UR after HoLEP. Materials and Methods 336 patients, which underwent HoLEP for a symptomatic benign prostatic hyperplasia between July 2008 and March 2012, were included in this study. Urethral catheters were routinely removed one or two days after surgery. UR was defined as the need for an indwelling catheter placement following a failure to void after catheter removal. Demographic and clinical parameters were compared between the UR (n = 37) and the non-urinary retention (non-UR; n = 299) groups. Results The mean age of patients was 68.3 (±6.5) years and the mean operative time was 75.3 (±37.4) min. Thirty seven patients (11.0%) experienced a postoperative UR. UR patients voided catheter free an average of 1.9 (±1.7) days after UR. With regard to the causes of UR, 24 (7.1%) and 13 (3.9%) patients experienced a blood clot-related UR and a non-clot related UR respectively. Using multivariate analysis (p<0.05), we found significant differences between the UR and the non-UR groups with regard to a morcellation efficiency (OR 0.701, 95% CI 0.498–0.988) and a bleeding-related complication, such as, a reoperation for bleeding (OR 0.039, 95% CI 0.004–0.383) or a transfusion (OR 0.144, 95% CI 0.027–0.877). Age, history of diabetes, prostate volume, pre-operative post-void residual, bladder contractility index, learning curve, and operative time were not significantly associated with the UR (p>0.05). Conclusions De novo UR after HoLEP was found to be self-limited and it was not related to learning curve, patient age, diabetes, or operative time. Efficient morcellation and careful control of bleeding, which reduces clot formation, decrease the risk of UR after HoLEP. PMID:24465454

  2. [Investigation of changes in sexual and ejaculatory functions after holmium laser enucleation of the prostate (HoLEP)].

    PubMed

    Ishikawa, Ryuta; Shitara, Toshiya; Hirayama, Takahiro; Wakatabe, Yoji; Dobashi, Masato; Sugita, Yoshiko; Kubo, Seiichi; Fujita, Tetsuo; Iwamura, Masatsugu; Baba, Shiro

    2014-06-01

    Changes in sexual function and ejaculatory function in patients who had undergone holmium laser enucleation of the prostate (HoLEP) were investigated using questionnaires. In this study, 77 patients on whom HoLEP was performed at our department from July 2010 to December 2010 were included. Of the 77 patients, the number of patients who could achieve an erection increased from 36 (46.8%) preoperatively to 52 (67.5%) postoperatively after HoLEP. Although postoperative ejaculatory dysfunction was found in 38 (73%) of 52 patients, 47 (90%) experienced orgasms, regardless of ejaculation, which is a high rate. With respect to ejaculatory satisfaction, patients who experienced an ejaculation had significantly higher satisfaction levels than those who did not. These results suggest that changes in postoperative ejaculatory function might affect satisfaction levels of ejaculation. PMID:25001640

  3. Management of Benign Prostatic Hyperplasia Larger than 100 ml: Simple Open Enucleation Versus Transurethral Laser Prostatectomy.

    PubMed

    Elkoushy, Mohamed A; Elhilali, Mostafa M

    2016-06-01

    Benign prostatic hyperplasia (BPH) is one of the most common causes of lower urinary tract symptoms (LUTS) in aging men. Over the age of 60, more than a half of men have BPH and/or bothersome LUTS. Contemporary guidelines advocate surgery as the standard of care for symptomatic BPH after failure of medical therapy, where the choice of the appropriate surgical procedure depends on the prostate size. Transurethral resection of the prostate (TURP) and simple open prostatectomy (OP) have been considered for decades the reference-standard techniques for men with prostate smaller and larger than 80 ml, respectively. However, both procedures are potentially associated with considerable perioperative morbidity which prompted the introduction of a variety of minimally invasive surgical techniques with comparable long-term outcomes compared to TURP and OP. Nevertheless, the management of prostates larger than 100 ml remains a clinical challenge. Transurethral anatomical enucleation of the prostate utilizing different laser energy represents an excellent alternative concept in transurethral BPH surgery. These procedures gained popularity and demonstrated similar outcomes to OP with the advantages of favorable morbidity profiles and shorter catheter time and hospital stay. Despite the fact that OP remains a viable treatment option for patients with bothersome LUTS secondary to very large prostates, this procedure has been to a large extent replaced by these emerging enucleation techniques. Given the advent of surgical alternatives, the current review presents an evidence-based comparison of the efficacy and safety profile of the currently available transurethral laser techniques with the standard OP for the management of BPH due to adenomas larger than 100 ml. PMID:27048160

  4. Towards optimizing prostate tissue retrieval following holmium laser enucleation of the prostate (HoLEP): Assessment of two morcellators and review of literature

    PubMed Central

    Elshal, Ahmed M.; Mekkawy, Ramy; Laymon, Mahmoud; El-Assmy, Ahmed; El-Nahas, Ahmed R.

    2015-01-01

    Introduction: We assess different approaches to retrieve the enucleated adenoma after transurethral enucleation of the prostate, particularly using the holmium laser. Methods: A retrospective review through our prospectively maintained database was performed looking for safety and efficacy of two morcellators. The enucleation phase of the holmium laser enucleation of the prostate (HoLEP) was classically performed followed by retrieval of the intravesical adenoma using either the Piranha (Wolf Inc., Knittlingen, Germany) or VersaCut (Lumenis) morcellator. A PubMed-MEDLINE search was conducted for all transurethral enucleation procedures and relevant data regarding methods of prostate tissue retrieval were extracted. Results: Strictly limiting the study to 3 reusable blades with each morcellator, we performed 67 and 55 consecutive procedures with Piranha and VersaCut, respectively. There was no significant difference between the two morcellators regarding perioperative complications, apart from 5 bladder mucosal injuries with the VersaCut (9%). Furthermore, there were similar retrieved tissue weight, mechanical problems-rate, catheter-time and hospital-stay in both morcellators. However, the Piranha morcellator needed significantly less morcellation-time, needed to use cold loop to remove non-morcellated pieces and to score the adenoma by laser for better bite of the adenoma, and had a higher median morcellation-rate 6.2 (rate: 2.8–12) g/min. Despite little reporting on morcellation, we had data on the tissue retrieval rate (2.6 to 6.5 g/min with Piranha and 1.9 to 11 g/min with VersaCut. Furthermore, bladder mucosal injury was reported in 1.4% and 0.7 to 5.7% with Piranha and VersaCut, respectively; bladder perforation with VersaCut was experienced in about 0.1 to 1.5% of patients. Our study is limited by its non-randomization. Conclusion: The Piranha morcellator was the most efficient and safe way to retrieve tissue after a transurethral enucleation of a prostate

  5. Introducing holmium laser enucleation of the prostate alongside transurethral resection of the prostate improves outcomes of each procedure

    PubMed Central

    Wilson, N; Acher, P; Lodge, R; Young, A

    2013-01-01

    Introduction Holmium laser enucleation of the prostate (HoLEP) is recognised as an alternative to transurethral resection of the prostate (TURP). HoLEP has been demonstrated to be at least as effective as TURP with less morbidity but its introduction to practice has been limited in part by the learning curve of a novel procedure. This study examined the effects of introducing HoLEP alongside an established practice of TURP on early morbidity and length of hospital stay (LOS). Methods A retrospective review of all patients who underwent HoLEP and TURP between April 2007 and July 2011 was undertaken. HoLEP was introduced in April 2008; patients undergoing TURP before this were considered as a historical control group. Data were collected concerning resection/enucleation weight, blood transfusions and LOS. Results Overall, 772 patients underwent HoLEP or TURP within the 52-month study period: 164 underwent TURP prior to the introduction of HoLEP (TURP-A), 425 had TURP after the introduction of HoLEP (TURP-B) and 183 underwent HoLEP. The mean removed weight was 24g (standard deviation [SD]: 21g) for TURP-A, 19g for TURP-B (SD: 16g) and 38g (SD: 32g) for HoLEP (p<0.005). Blood transfusion rates were 5.5%, 2.2% and 1.6% for the TURP-A, TURP-B and HoLEP groups respectively (p<0.05). For TURP-A patients, the mean LOS was 5.6 days (SD: 3.5 days, 95% confidence interval [CI]: 5.3–6.0 days). The mean LOS for TURP-B patients was 4.4 days (SD: 4.4 days, 95% CI: 4.2–4.8 days). HoLEP patients had a mean LOS of 3.0 days (SD: 3.0 days, 95% CI: 2.6–3.4 days). Conclusions The introduction of HoLEP alongside TURP is associated with lower rates of blood transfusion and shorter LOS for all patients. This is likely to be due to the use of HoLEP rather than TURP in patients with larger prostates, who are more likely to have complications. PMID:23838502

  6. Comparison of Photoselective Vaporization versus Holmium Laser Enucleation for Treatment of Benign Prostate Hyperplasia in a Small Prostate Volume

    PubMed Central

    Kim, Kang Sup; Choi, Jin Bong; Bae, Woong Jin; Kim, Su Jin; Cho, Hyuk Jin; Hong, Sung-Hoo; Lee, Ji Youl; Kim, Sang Hoon; Kim, Hyun Woo; Cho, Su Yeon; Kim, Sae Woong

    2016-01-01

    Objective Photoselective vaporization of the prostate (PVP) using GreenLight and Holmium laser enucleation of the prostate (HoLEP) is an important surgical technique for management of benign prostate hyperplasia (BPH). We aimed to compare the effectiveness and safety of PVP using a 120 W GreenLight laser with HoLEP in a small prostate volume. Methods Patients who underwent PVP or HoLEP surgery for BPH at our institutions were reviewed from May 2009 to December 2014 in this retrospective study. Among them, patients with prostate volumes < 40 mL based on preoperative trans-rectal ultrasonography were included in this study. Peri-operative and post-operative parameters—such as International Prostate Symptom Score (IPSS), quality of life (QoL), maximum urinary flow rate (Qmax), post-void residual urine volume (PVR), and complications—were compared between the groups. Results PVP was performed in 176 patients and HoLEP in162 patients. Preoperative demographic data were similar in both groups, with the exception of PVR. Operative time and catheter duration did not show significant difference. Significant improvements compared to preoperative values were verified at the postoperative evaluation in both groups in terms of IPSS, QoL, Qmax, and PVR. Comparison of the postoperative parameters between the PVP and HoLEP groups demonstrated no significant difference, with the exception of IPSS voiding subscore at 1 month postoperatively (5.9 vs. 3.8, P< 0.001). There was no significant difference in postoperative complications between the two groups. Conclusion Our data suggest that PVP and HoLEP are efficient and safe surgical treatment options for patients with small prostate volume. PMID:27227564

  7. Holmium Laser Enucleation of the Prostate for Benign Prostatic Hyperplasia: Effectiveness, Safety, and Overcoming of the Learning Curve

    PubMed Central

    Hwang, Jin Chul; Park, Sang Myung

    2010-01-01

    Purpose To examine the efficacy and safety of holmium laser enucleation of the prostate (HoLEP) for the surgical treatment of benign prostatic hyperplasia and to estimate the time to overcome the learning curve. Materials and Methods From May 2008 to October 2009, 164 consecutive patients treated with HoLEP were enrolled in this study. International Prostate Symptom Score (IPSS), peak urinary flow rate (Qmax), and postvoid residual urine (PVR) were documented preoperatively and at 6 weeks and 3, 6, 12, and 18 months postoperatively. The 164 study subjects were divided into 3 groups (group 1 the first 50 patients treated, group 2 the second 50, and group 3 the third 64), and perioperative data and complications were analyzed in these groups to determine the learning curve. In addition, the inverse and upward techniques were compared in terms of the effects and the stability of morcellation. Results The mean patient age was 69 years, and the average operation time was 62 minutes (range, 20-208 minutes). Mean prostate volume was 54.2 ml and mean resected tissue weight was 18.6 g. Postoperatively, IPSS and PVR decreased and Qmax increased significantly. Postoperative complications were transient incontinence (8.5%), urinary retention (4.3%), hematuria (3.0%), urinary tract infection (1.2%), and urethral stricture (0.6%), and intraoperative complications were minor capsular perforation (4%) and bladder injury (8%). Conclusions HoLEP was found to be effective and safe regardless of prostate size. We recommend that a systematic educational program be established to reduce the learning curve. PMID:20856646

  8. Holmium laser enucleation of the prostate: surgical, functional, and quality-of-life outcomes upon extended follow-up

    PubMed Central

    Alkan, Ilter; Ozveri, Hakan; Akin, Yigit; Ipekci, Tumay; Alican, Yusuf

    2016-01-01

    ABSTRACT Objectives: To evaluate the long-term surgical, functional, and quality-of-life (QoL) outcomes after Holmium laser enucleation of the prostate (HoLEP) in patients with symptomatic benign prostatic hyperplasia (BPH). Materials and Methods: We retrospectively reviewed recorded data on patients who underwent HoLEP between June 2002 and February 2005. Ninety-six patients were enrolled. Demographic, perioperative, and postoperative data were recorded. On follow-up, International Prostate Symptom Scores (IPSSs), prostate-specific antigen (PSA) levels, QoL scores, peak uroflowmetric data (Qmax values), and post-voiding residual urine volumes (PVR volumes), were recorded. Complications were scored using the Clavien system. Statistical significance was set at p<0.05. Results: The mean follow-up time was 41.8±34.6 months and the mean patient age 73.2±8.7 years. The mean prostate volume was 74.6±34.3mL. Significant improvements in Qmax values, QoL, and IPSSs and decreases in PSA levels and PVR volumes were noted during follow-up (all p values=0.001). The most common complication was a requirement for re-catheterisation because of urinary retention. Two patients had concomitant bladder tumours that did not invade the muscles. Eight patients (8.3%) required re-operations; three had residual adenoma, three urethral strictures, and two residual prostate tissue in the bladder. Stress incontinence occurred in one patient (1%). All complications were of Clavien Grade 3a. We noted no Clavien 3b, 4, or 5 complications during follow-up. Conclusions: HoLEP improved IPSSs, Qmax values, PVR volumes, and QoL and was associated with a low complication rate, during extended follow-up. Thus, HoLEP can be a viable option to transurethral resection of the prostate. PMID:27256184

  9. Preoperative Factors Affecting Postoperative Early Quality of Life During the Learning Curve of Holmium Laser Enucleation of the Prostate

    PubMed Central

    Cho, Kang Jun; Kim, Hyo Sin; Koh, Jun Sung; Han, Seung Bum; Kim, Sang Hoon; Kim, Hyun Woo; Cho, Su Yeon

    2013-01-01

    Purpose The aim of this study was to investigate the preoperative factors related to early quality of life (QoL) in patients with benign prostatic hyperplasia after holmium laser enucleation of the prostate (HoLEP) during the surgeon's learning curve. Methods The medical records of 82 patients with a follow-up period of at least 3 months who were treated with HoLEP during the time of a surgeon's learning curve were analyzed retrospectively. We divided the patients into two groups on the basis of the QoL component of the International Prostate Symptom Score (IPSS) 3 months after HoLEP: the high QoL group (IPSS/QoL≤3) and the low QoL group (IPSS/QoL≥4). Preoperative factors in each group were compared, including prostate volume, prostate-specific antigen, history of acute urinary retention (AUR), urgency incontinence, IPSS, and urodynamic parameters. Detrusor underactivity was defined as a bladder contractility index less than 100 on urodynamic study. Results A total of 61 patients (74.3%) had a high QoL, whereas 21 (25.7%) had a low QoL. A history of AUR, detrusor pressure on maximal flow (PdetQmax), bladder outlet obstruction grade, bladder contractility index, and detrusor underactivity were associated with postoperative QoL in the univariate analysis. In the multivariate analysis, a history of AUR and PdetQmax were independent factors affecting postoperative QoL. Conclusions A history of AUR and bladder contractility affect early QoL, and preoperative urodynamic study plays an important role in the proper selection of patients during the HoLEP learning curve. PMID:23869273

  10. Holmium Laser Enucleation of the Prostate: Comparison of Immediate Postoperative Outcomes in Patients with and without Antithrombotic Therapy

    PubMed Central

    Bishop, Conrad V.; Liddell, Heath; Ischia, Joseph; Paul, Eldho; Appu, Sree; Frydenberg, Mark; Pham, Trung

    2013-01-01

    Objective To compare the immediate postoperative outcomes of patients with benign prostatic hyperplasia undergoing Holmium laser enucleation of the prostate (HOLEP) with and without full anticoagulation or antiplatelet therapy at the time of surgery. Materials and Methods A retrospective review was performed on a series of consecutive patients undergoing HOLEP at our institution by a single surgeon from February 2004 to September 2010. Demographic, surgical, pathological and outcome data were collected. Two cohorts were identified on the basis of antithrombotic therapy at the time of surgery. Patients who continued on aspirin, aspirin/dipyridamole, clopidogrel and warfarin throughout the surgery were included in the antithrombotic cohort. Univariate analysis was performed to determine differences in outcomes between the 2 cohorts. Results Total 125 consecutive patients underwent HOLEP with 52 patients on antithrombotic therapy at the time of surgery and 73 patients were not on antithrombotic therapy during surgery. Patients in the antithrombotic group were older (75.1 ±7.5 vs. 71.7 ± 8.3 years; p = 0.02) and had a higher median ASA physical status (3 (3-3) vs. 2 (2-3), p < 0.0001). The mean operating time and median specimen volume were not significantly different between the 2 cohorts. The median length of stay (2 (1-3) vs. 1 (1-2) d, p = 0.014) was longer in the antithrombotic cohort. The transfusion rate (7.7 vs. 0%, p = 0.028) was predictably higher in the antithrombotic cohort. No patients required re-operation for bleeding. Conclusions The use of HOLEP in patients on antithrombotic therapy is safe despite the higher surgical risk profile of that particular patient population and the potential increased risk for significant bleeding. PMID:24917753

  11. Relationship of Postoperative Recatheterization and Intraoperative Bladder Distention Volume in Holmium Laser Enucleation of the Prostate for Benign Prostatic Hyperplasia

    PubMed Central

    Kim, Hyeon Jun; Lee, Han Yi; Song, Sang Hun

    2013-01-01

    Purpose The purpose of this study was to identify the risk factors for recatheterization after holmium laser enucleation of the prostate (HoLEP). Materials and Methods A total of 166 consecutive patients treated with HoLEP by a single surgeon from January 2010 to June 2011 were enrolled in this study. We collected data on preoperative and intraoperative parameters, including intraoperative bladder distention volume. The patients were divided into two groups. Group 1 included patients who voided successfully after removal of the catheter, and group 2 included patients who required recatheterization. Analysis and comparison of the perioperative parameters of both groups was performed for identification of risk factors for recatheterization. Results Recatheterization was required in 9 of 166 (5.4%) patients. No significant differences in age or preoperative parameters, including prostate-specific antigen, prostate volume, International Prostate Symptom Score, peak flow rate, postvoid residual urine, maximal bladder capacity, and Abrahams Griffiths number, were observed between the two groups. Of the intraoperative parameters, intraoperative bladder distention volume was significantly smaller in group 1 than in group 2 (700.65 mL vs. 897.78 mL, p<0.001). In the multivariate logistic regression analysis, after adjustment for other variables, intraoperative bladder distention volume was found to be a statistically significant risk factor for postoperative recatheterization (hazard ratio, 1.006; confidence interval, 1.002 to 1.010; p=0.002). Conclusions Nine of 166 (5.4%) patients failed to void after HoLEP and required catheterization. Intraoperative bladder distention volume was found to be a statistically significant risk factor for recatheterization in this patient group. PMID:23549294

  12. Postoperative Infectious Complications in Our Early Experience With Holmium Laser Enucleation of the Prostate for Benign Prostatic Hyperplasia

    PubMed Central

    Tanaka, Kazushi; Haraguchi, Takahiro; Yamamichi, Fukashi; Muramaki, Mototsugu; Miyake, Hideaki; Fujisawa, Masato

    2013-01-01

    Purpose The objective of this study was to retrospectively investigate postoperative infectious complications (PICs) in our early experience with holmium laser enucleation of the prostate (HoLEP) followed by mechanical morcellation for symptomatic benign prostatic hyperplasia. Materials and Methods A retrospective review was performed of the clinical data for 90 consecutive patients who underwent HoLEP at our institution between February 2008 and March 2011. All patients were evaluated for the emergence of PICs, including prophylactic antibiotic administration (PAA) and the influence of the kind or duration of PAA on PIC. The details of cases with PICs were also examined. Results The patients' mean age was 71 years (range, 50 to 95 years), and their mean prostate volume was 60 mL (range, 2 to 250 mL). There were 7 cases (7.78%) with PICs; in detail, 3 patients were diagnosed with prostatitis, 2 with pyelonephritis, and 2 with epididymitis. Three patients had positive urine cultures: 1 had Serratia marcescens/Proteus mirabilis, 1 had S. marcescens, and 1 had Klebsiella pneumonia; only one case had urological sepsis. Our statistical data showed no significant differences between 2 or fewer days and 3 or more days of PAA and PIC occurrence. There was also no significant effect on PIC occurrence of sulbactam/ampicillin compared with other antibiotics. Conclusions The results of this retrospective study showed that PIC occurrence did not depend on the duration or the kind of PAA. Further prospective study is necessary for the evaluation and establishment of prophylactic measures for PICs. PMID:23526729

  13. Transurethral holmium laser enucleation of prostates (HoLEP) larger than 80 g

    NASA Astrophysics Data System (ADS)

    Kuntz, Rainer M.; Lehrich, Karin; Fayad, Amr

    2001-05-01

    In this prospective study, the efficiency of HoLEP inpatients with prostates larger than 80 grams was to be evaluated. 64 urodynamically obstructed patients with prostate glands of 103 (80-230) grams of weight underwent HoLEP (80 W, 2.0 J, 40 Hz, 550 nm bare laser fibers). The resected weight was 70 (50-200) grams, the resection time was 120.5 (83-170) min., the average resection weight was 0.7 gm/min. The postoperative catheter time was 1.3 (1-3) days. The postoperative hospital stay was 2.5 (1-7) days. HoLEP induced a significant, pronounced and immediate improvement of lower urinary tract symptoms and micturition. The symptom score decreased from 22.3 preoperatively to 5.7 one week and 2.8 one year postoperatively. The peak urinary flow rate of 4.3 ml/sec preoperatively increased to 22 ml/sec one week and 32 ml/sec one year postoperatively. The residual urine dropped from 267 ml preoperatively to 11.5 ml one week and 5.0 ml one year postoperatively. There was one incident of postoperative arterial bleeding, one patient developed urethral stricture and two patients needed a second HoLEP. HoLEP appeared to be a highly effective treatment for prostates larger than 80 grams, with excellent functional results, minor blood loss, low complication rate and very short catheter time and hospital stay.

  14. Thulium laser enucleation of the prostate is a safe and a highly effective modality for the treatment of benign prostatic hyperplasia - Our experience of 236 patients

    PubMed Central

    Ketan, P. Vartak; Prashant, H. Salvi

    2016-01-01

    Context: Thulium LASER is fast emerging as a safe and effective modality for benign prostatic hyperplasia (BPH). Still, compared to holmium laser transurethral enucleation of the prostate (HoLEP) the number of institutes all over the world using Thulium LASER are limited. This is our effort to bring the statistical facts about the safety and effectivity of Thulium LASER. Aims: To study the efficacy of thulium laser enucleation of the prostate (ThuLEP). Settings and Design: All patients in the stipulated period were documented for all parameters and were evaluated. The results were tabulated. Subjects and Materials: (1) Two hundred and thirty-six patients with symptomatic BPH were treated with ThuLEP between March 2010 and September 2014 at our institute by a single surgeon. (2) The inclusion criteria were maximum urinary flow rate (Qmax) <15 ml/s, International Prostate Symptoms Score (IPSS) >15 or acute retention of urine with the failure of catheter trial or Acute retention of urine with prior history of severe bladder outlet obstruction. (3) Patients evaluated by: Digital rectal examination, uroflowmetry, IPSS, prostate-specific antigen (PSA), blood and urine routine tests, abdominal usage with trains rectal ultrasonography (TRUS), TRUS guided biopsies. Statistical Analysis Used: Not used. Results: (1) ThuLEP was a highly effective procedure as compared to all other procedures like HOLEP, TURP in terms of catheterization time, hospital stay, and drop in hemoglobin (Hb). (2) Catheterization time: 25.22 h (224 patients within 24 h and 12 patients within 48 h). (3) Hospital stay: 24–36 h 218 patients (92.3%), 36–48 h 18 patients (7.6%). (4) Drop in Hb: 0.8 ± 0.42 g/dl. (5) Average operative time: 56.91 min. Conclusions: Thulium LASER is a safe and highly effective LASER in terms of blood loss, speed of tissue resection, drop in serum PSA, and versatility of prostatic resection. PMID:26834407

  15. Holmium laser enucleation versus simple prostatectomy for treating large prostates: Results of a systematic review and meta-analysis

    PubMed Central

    Jones, Patrick; Alzweri, Laith; Rai, Bhavan Prasad; Somani, Bhaskar K.; Bates, Chris; Aboumarzouk, Omar M.

    2015-01-01

    Objective To compare and evaluate the safety and efficacy of holmium laser enucleation of the prostate (HoLEP) and simple prostatectomy for large prostate burdens, as discussion and debate continue about the optimal surgical intervention for this common pathology. Materials and methods A systematic search was conducted for studies comparing HoLEP with simple prostatectomy [open (OP), robot-assisted, laparoscopic] using a sensitive strategy and in accordance with Cochrane collaboration guidelines. Primary parameters of interest were objective measurements including maximum urinary flow rate (Qmax) and post-void residual urine volume (PVR), and subjective outcomes including International Prostate Symptom Score (IPSS) and quality of life (QoL). Secondary outcomes of interest included volume of tissue retrieved, catheterisation time, hospital stay, blood loss and serum sodium decrease. Data on baseline characteristics and complications were also collected. Where possible, comparable data were combined and meta-analysis was conducted. Results In all, 310 articles were identified and after screening abstracts (114) and full manuscripts (14), three randomised studies (263 patients) were included, which met our pre-defined inclusion criteria. All these compared HoLEP with OP. The mean transrectal ultrasonography (TRUS) volume was 113.9 mL in the HoLEP group and 119.4 mL in the OP group. There was no statistically significant difference in Qmax, PVR, IPSS and QoL at 12 and 24 months between the two interventions. OP was associated with a significantly shorter operative time (P = 0.01) and greater tissue retrieved (P < 0.001). However, with HoLEP there was significantly less blood loss (P < 0.001), patients had a shorter hospital stay (P = 0.03), and were catheterised for significantly fewer hours (P = 0.01). There were no significant differences in the total number of complications recorded amongst HoLEP and OP (P = 0.80). Conclusion The results of the meta

  16. Efficacy and safety of holmium laser enucleation of the prostate for extremely large prostatic adenoma in patients with benign prostatic hyperplasia

    PubMed Central

    Kim, Myong; Piao, Songzhe; Lee, Hahn-Ey; Kim, Sung Han

    2015-01-01

    Purpose To evaluate the efficacy and safety of holmium laser enucleation of the prostate (HoLEP) for extremely large prostates. Materials and Methods Patients undergoing HoLEP between July 2008 and December 2013 from the Seoul National University Hospital Benign Prostatic Hyperplasia Database Registry were retrospectively analyzed. The patients were divided into three groups according to their total prostate volume (TPV): group A (TPV<100 mL), group B (100 mL≤TPV<200 mL), and group C (TPV≥200 mL); the clinical data of the three groups were compared. All patients were followed up 2 weeks, 3 months, and 6 months after surgery. Results A total of 502 patients (group A, 426; group B, 70; group C, 6) with a mean age of 69.0 (standard deviation, ±7.3) years were included in our analysis. The mean prostate volume and prostate-specific antigen level were 68.7±36.9 mL and 4.15±4.24 ng/mL, respectively. The enucleation and morcellation times were longer in group C (p<0.001), and the enucleation efficacy was higher in this group (p<0.001, R2=0.399). Moreover, the mean postoperative catheterization and hospitalization periods were significantly longer in group C (p=0.004 and p=0.011, respectively). However, there were no significant differences between the groups in any other postoperative events, including recatheterization, reoperation, urinary tract infection, clot retention, and bladder neck contracture (p range, 0.516-0.913). One patient in group C experienced recurrence of the urethral stricture. Conclusions HoLEP in patients with an extremely large prostate can be performed efficiently and safely. PMID:25763126

  17. Enucleation Procedure Manual.

    ERIC Educational Resources Information Center

    Davis, Kevin; Poston, George

    This manual provides information on the enucleation procedure (removal of the eyes for organ banks). An introductory section focuses on the anatomy of the eye and defines each of the parts. Diagrams of the eye are provided. A list of enucleation materials follows. Other sections present outlines of (1) a sterile procedure; (2) preparation for eye…

  18. Severe postoperative dyspnea caused by neglected massive intraperitoneal fluid collection during laser enucleation and morcellation of the prostate: a case report

    PubMed Central

    Kim, Sung-Hoon; Son, Hyo-Jung; Kim, Jae-Won; Kong, Yu-Gyeong; Hwang, Jai-Hyun

    2016-01-01

    Laser enucleation and morcellation of the prostate is an increasingly used surgical management of benign prostatic hyperplasia. However, it can cause several complications including capsular perforation, ureteral orifice injury, and bladder mucosal morcellation injury. Herein, we report a case of severe postoperative dyspnea caused by neglected massive intraperitoneal fluid collection during laser surgery of the prostate. The patient experienced massive abdominal distension and severe respiratory difficulty after the procedure. Although immediate postoperative cystogram showed no leakage of contrast dye, the computed tomography scan of the abdomen and pelvis showed massive fluid collection in the abdominal pelvic cavity suggesting bladder wall injury. After percutaneous drainage of intraperitoneal fluid, abdominal distention and dyspnea were relieved. PMID:27066210

  19. Holmium Laser Enucleation of the Prostate With Percutaneous Nephrostomy Into the Transplanted Kidney in Patient With Severe Benign Prostatic Hyperplasia With Vesicoureteral Reflux - A Case Report.

    PubMed

    Nohara, Takahiro; Matsuyama, Satoko; Shima, Takashi; Kawaguchi, Shohei; Seto, Chikashi

    2016-01-01

    A 66-year-old male, who had received renal transplantation 10 years before, was admitted to our hospital with urinary retention. The prostate volume was 169.2 ml. Furthermore, grade 5 vesicoureteral reflux (VUR) was shown in the cystography. Holmium laser enucleation of prostate (HoLEP) was performed, and percutaneous nephrostomy to the transplanted kidney was performed simultaneously to prevent from severe perioperative infection. After that, renal graft function improved and no urinary retention reoccurred, although surgical repair against VUR was necessary 10 months after HoLEP. We conclude that surgical treatment for BPH after kidney transplantation should be strongly considered with care for infections. PMID:26793574

  20. Holmium Laser Enucleation of the Prostate With Percutaneous Nephrostomy Into the Transplanted Kidney in Patient With Severe Benign Prostatic Hyperplasia With Vesicoureteral Reflux – A Case Report

    PubMed Central

    Nohara, Takahiro; Matsuyama, Satoko; Shima, Takashi; Kawaguchi, Shohei; Seto, Chikashi

    2015-01-01

    A 66-year-old male, who had received renal transplantation 10 years before, was admitted to our hospital with urinary retention. The prostate volume was 169.2 ml. Furthermore, grade 5 vesicoureteral reflux (VUR) was shown in the cystography. Holmium laser enucleation of prostate (HoLEP) was performed, and percutaneous nephrostomy to the transplanted kidney was performed simultaneously to prevent from severe perioperative infection. After that, renal graft function improved and no urinary retention reoccurred, although surgical repair against VUR was necessary 10 months after HoLEP. We conclude that surgical treatment for BPH after kidney transplantation should be strongly considered with care for infections. PMID:26793574

  1. Pilot study of the clinical efficacy of ejaculatory hood sparing technique for ejaculation preservation in Holmium laser enucleation of the prostate.

    PubMed

    Kim, M; Song, S H; Ku, J H; Kim, H-J; Paick, J-S

    2015-01-01

    We explored the effectiveness of ejaculatory hood sparing technique to Holmium laser enucleation of the prostate (HoLEP) for ejaculation preservation. From June 2010 to July 2011, 52 sexually active patients with sufficient ejaculate underwent HoLEP. Twenty-six patients received the ejaulatory hood sparing technique during HoLEP (EH-HoLEP group). The other 26 patients underwent conventional HoLEP (conventional-HoLEP group). In the EH-HoLEP group, paracollicular and supracollicular tissue >1 cm proximal to the verumontanum was preserved. The mean follow-up period was 9.7 months (range 3-12). There was no significant difference in patient characteristics and perioperative parameters, including age, prostate volume, International Index of Erectile Function score, operation time, weight of the enucleated tissue and the amount of laser energy. Semen was unchanged, decreased or vanished in 4 (15.4%), 8 (30.8%) and 17 (53.8%) EH-HoLEP patients, respectively. In the conventional-HoLEP group, semen was unchanged, decreased or vanished in 0 (0.0%%), 7 (26.9%) and 19 (73.1%) patients, respectively. Overall success rate of ejaculation preservation was 46.2% in the EH-HoLEP group and 26.9% in the conventional-HoLEP group (P = 0.249). Application of an ejaculatory hood sparing technique to HoLEP could not improve the success rate for ejaculation preservation. This was likely due to the surgical characteristics of HoLEP, which enable complete removal of the apical tissue. In this condition, simply preserved ejaculatory hood tissue seems not to be sufficient to obviate retrograde ejaculation. For the maintenance of antegrade ejaculation, it is postulated that a part of apical tissue should be preserved as well. PMID:25007827

  2. AB070. Comparison of photoselective vaporization versus holmium laser enucleation for treatment of benign prostate hyperplasia in a small prostate volume

    PubMed Central

    Bae, Woong Jin; Bashraheel, Fahad; Choi, Sae Woong; Kim, Su Jin; Yoon, Byung Il; Kim, Sae Woong

    2016-01-01

    Objective Photoselective vaporization of the prostate (PVP) using GreenLight and Holmium laser enucleation of the prostate (HoLEP) is an important surgical technique for management of benign prostate hyperplasia (BPH). We aimed to compare the effectiveness and safety of PVP using a 120 W GreenLight laser with HoLEP in a small prostate volume. Methods Patients who underwent PVP or HoLEP surgery for BPH at our institutions were reviewed from May 2009 to December 2014 in this retrospective study. Among them, patients with prostate volumes <40 mL based on preoperative trans-rectal ultrasonography were included in this study. Peri-operative and post-operative parameters—such as International Prostate Symptom Score (IPSS), quality of life (QoL), maximum urinary flow rate (Qmax), post-void residual urine volume (PVR), and complications—were compared between the groups. Results PVP was performed in 176 patients and HoLEP in162 patients. Preoperative demographic data were similar in both groups, with the exception of PVR. Operative time and catheter duration did not show significant difference. Significant improvements compared to preoperative values were verified at the postoperative evaluation in both groups in terms of IPSS, QoL, Qmax, and PVR. Comparison of the postoperative parameters between the PVP and HoLEP groups demonstrated no significant difference, with the exception of IPSS voiding subscore at one month postoperatively (5.9 vs. 3.8, P<0.001). There was no significant difference in postoperative complications between the two groups. Conclusions Our data suggest that PVP and HoLEP are efficient and safe surgical treatment options for patients with small prostate volume.

  3. Application of the Modified Clavien Classification System to 402 Cases of Holmium Laser Enucleation of the Prostate for Benign Prostatic Hyperplasia

    PubMed Central

    Choi, Jong In; Moon, Kyung Young; Yoon, Jong Hyun; Na, Woong

    2014-01-01

    Purpose We attempted to evaluate the perioperative complications of holmium laser enucleation of the prostate (HoLEP) for benign prostatic hyperplasia by using the modified Clavien classification system (MCCS). Materials and Methods Targeting 402 patients who underwent HoLEP for benign prostatic hyperplasia performed by a single surgeon between July 2008 and January 2011, we investigated complications that occurred during and within 1 month after surgery and classified them into grade I to grade V on the basis of the MCCS. If two or more complications occurred in one patient, each complication was graded and counted. Results The mean age, prostate volume, operation time, hospital stay, and average follow-up period of 402 patients who underwent HoLEP were 68.8 years (range, 52-84 years), 53.2 g (range, 23-228 g), 58.2 minutes (range, 20-230 minutes), 4.5 days (range, 2-7 days), and 9 months (range, 4-27 months), respectively; 78 complications occurred in 71 of the patients (morbidity rate, 17.6%). In MCCS grade I, complications occurred in 54 cases (69.2%); in grade II, complications occurred in 19 cases (24.3%); in grade III, complications occurred in 4 cases (5.1%); and in grade IV, 1 patient required intensive care unit care because of cerebral infarction (1.2%). There were no grade V complications. Conclusions The HoLEP-based MCCS complications classification was performed very quickly. However, MCCS, when compared with other measures of endoscopic prostate surgery experiences, including HoLEP, exposed the lack of accuracy in low grade classification and the inability to include late complications. PMID:24648872

  4. Holmium Laser Enucleation of the Prostate is Effective in the Treatment of Symptomatic Benign Prostatic Hyperplasia of Any Size Including a Small Prostate

    PubMed Central

    Lee, Min Ho; Yang, Hee Jo; Kim, Doo Sang; Lee, Chang Ho

    2014-01-01

    Purpose Although transurethral resection of the prostate (TURP) is considered the standard surgical treatment for benign prostatic hyperplasia (BPH), Holmium laser enucleation of the prostate (HoLEP) is replacing TURP. We compared TURP with HoLEP with matching for prostate size. Materials and Methods We retrospectively reviewed the medical charts of patients who underwent TURP and HoLEP performed by one surgeon at our institute. All patients were categorized into 3 groups on the basis of prostate size (group 1, <40 g; group 2, 40-79 g; and group 3, >80 g), and 45 patients were selected for each method. Results No major intraoperative complications were encountered. The mean resected tissue weight was 6.3, 18.3, and 28.0 g for groups 1, 2, and 3, respectively, for TURP and 8.7, 25.0, and 39.8 g, respectively, for HoLEP. The mean operation time was 51.8, 89.3, and 101.9 minutes for TURP and 83.6, 122.8, and 131.2 minutes for HoLEP in groups 1, 2, and 3, respectively. HoLEP had better resection efficacy than TURP for any size prostate, but there was no statistical difference between the methods. Both methods resulted in an immediate and significant improvement of International Prostate Symptom Score, peak urinary flow rates, and postvoid residual urine volume. Conclusions HoLEP is effective for BPH treatment, regardless of prostate size, even in a small prostate. The perioperative morbidity of HoLEP is also comparable to that of TURP. PMID:25405016

  5. Nonspecific Genitourinary Pain Improves after Prostatectomy Using Holmium Laser Enucleation of Prostate in Patients with Benign Prostatic Hyperplasia: A Prospective Study

    PubMed Central

    Kim, Sung Han; Oh, Seung-June

    2014-01-01

    Objective To investigate changes in nonspecific genitourinary discomfort or pain (GUDP) before and after holmium laser enucleation of prostate (HoLEP). GUDP associated with lower urinary tract symptoms (LUTS) is a common complaint among benign prostatic hyperplasia (BPH) patients, but very little is known about this clinical entity. Methods From February 2010 to August 2011, 100 HoLEP patients with complete clinical data at a single institution were enrolled in the study to analyze the degree of GUDP with a visual analog scale (VAS) from 0 to 10 points at baseline and at 3 and 6 months postoperatively, and to investigate any relationships between GUDP and urodynamics, uroflowmetry, and scores from the International Prostate Symptom Score (IPSS) questionnaire. Results Fifty-six patients had LUTS only, while the remaining 44 had both LUTS and GUDP. Pain was located in the suprapubic (42.0%), perineal/penile (33.0%), back (17.0%), and perianal (8.0%) regions. During the post-operative period, at six months, the VAS, IPSS, peak flow rate and post-void residual volume had improved significantly in 44 GUDP patients (p<0.010). GUDP had completely resolved in 40 (90.9%) patients and had decreased in four (9.1%) patients, while seven (12.5%) patients developed GUDP with voiding in the urethral and perineal areas by the third month postoperatively. When compared to patients with complete resolution, those with persistent GUDP were found to have a significantly higher preoperative presence of bladder outlet obstruction (BOO) as an independent risk factor (OR 6.173, 95% CI 1.132–1.323). Conclusion Both GUDP and LUTS improved significantly after HoLEP. Patients with significant preoperative BOO tended to have persistent GUDP after surgery. PMID:24901224

  6. Comparison of Predictive Factors for Postoperative Incontinence of Holmium Laser Enucleation of the Prostate by the Surgeons’ Experience During Learning Curve

    PubMed Central

    Tanaka, Kazushi; Yamamichi, Fukashi; Chiba, Koji; Fujisawa, Masato

    2016-01-01

    Purpose: To detect predictive factors for postoperative incontinence following holmium laser enucleation of the prostate (HoLEP) according to surgeon experience (beginner or experienced) and preoperative clinical data. Methods: Of 224 patients, a total of 203 with available data on incontinence were investigated. The potential predictive factors for post-HoLEP incontinence included clinical factors, such as patient age, and preoperative urodynamic study results, including detrusor overactivity (DO). We also classified the surgeons performing the procedure according to their HoLEP experience: beginner (<21 cases) and experienced (≥21 cases). Results: Our statistical data showed DO was a significant predictive factor at the super-short period (the next day of catheter removal: odds ratio [OR], 3.375; P=0.000). Additionally, patient age, surgeon mentorship (inverse correlation), and prostate volume were significant predictive factors at the 1-month interval after HoLEP (OR, 1.072; P=0.004; OR, 0.251; P=0.002; and OR, 1.008; P=0.049, respectively). With regards to surgeon experience, DO and preoperative International Prostate Symptom Score (inverse) at the super-short period, and patient age and mentorship (inverse correlation) at the 1-month interval after HoLEP (OR, 3.952; P=0.002; OR, 1.084; P=0.015; and OR,1.084; P=0.015; OR, 0.358; P=0.003, respectively) were significant predictive factors for beginners, and first desire to void (FDV) at 1 month after HoLEP (OR, 1.009; P=0.012) was a significant predictive factor for experienced surgeons in multivariate analysis. Conclusions: Preoperative DO, IPSS, patient age, and surgeon mentorship were significant predictive factors of postoperative patient incontinence for beginner surgeons, while FDV was a significant predictive factors for experienced surgeons. These findings should be taken into account by surgeons performing HoLEP to maximize the patient’s quality of life with regards to urinary continence. PMID

  7. Holmium Laser Enucleation versus Transurethral Resection in Patients with Benign Prostate Hyperplasia: An Updated Systematic Review with Meta-Analysis and Trial Sequential Analysis

    PubMed Central

    Ruan, Xiao-Lan; Weng, Hong; Liu, Tong-Zu; Wang, Xiao; Zhang, Chao; Meng, Zhe; Wang, Xing-Huan

    2014-01-01

    Background Holmium laser enucleation (HoLEP) in surgical treatment of benign prostate hyperplasia (BPH) potentially offers advantages over transurethral resection of the prostate (TURP). Methods Published randomized controlled trials (RCTs) were identified from PubMed, EMBASE, Science Citation Index, and the Cochrane Library up to October 10, 2013 (updated on February 5, 2014). After methodological quality assessment and data extraction, meta-analysis was performed using STATA 12.0 and Trial Sequential Analysis (TSA) 0.9 software. Results Fifteen studies including 8 RCTs involving 855 patients met the criteria. The results of meta-analysis showed that: a) efficacy indicators: there was no significant difference in quality of life between the two groups (P>0.05), but compared with the TURP group, Qmax was better at 3 months and 12 months, PVR was less at 6, 12 months, and IPSS was lower at 12 months in the HoLEP, b) safety indicators: compared with the TURP, HoLEP had less blood transfusion (RR 0.17, 95% CI 0.06 to 0.47), but there was no significant difference in early and late postoperative complications (P>0.05), and c) perioperative indicators: HoLEP was associated with longer operation time (WMD 14.19 min, 95% CI 6.30 to 22.08 min), shorter catheterization time (WMD −19.97 h, 95% CI −24.24 to −15.70 h) and hospital stay (WMD −25.25 h, 95% CI −29.81 to −20.68 h). Conclusions In conventional meta-analyses, there is no clinically relevant difference in early and late postoperative complications between the two techniques, but HoLEP is preferable due to advantage in the curative effect, less blood transfusion rate, shorter catheterization duration time and hospital stay. However, trial sequential analysis does not allow us to draw any solid conclusion in overall clinical benefit comparison between the two approaches. Further large, well-designed, multicentre/international RCTs with long-term data and the comparison between the two approaches remain open

  8. Efficacy and safety profile of a novel technique, ThuLEP (Thulium laser enucleation of the prostate) for the treatment of benign prostate hypertrophy. Our experience on 148 patients

    PubMed Central

    2012-01-01

    Background Over the past years laser technology has played a predominant role in prostate surgery, for the treatment of benign prostate hypertrophy (BPH). Various laser devices have been introduced in clinical practice, showing good results in terms of complications and urodynamic outcomes efficacy compared with TURP and Open Prostatectomy. In this study we describe the efficacy and the safety profile of a novel laser technique, ThuLEP (Thulium Laser Enucleation of Prostate) that permits a complete anatomical endoscopic enucleation of prostatic adenoma independently to prostate size. Methods 148 patients with a mean age of 68.2 years were enrolled between September 2009 and March 2012 (36 months), and treated for BPH with ThuLEP. Every patient was evaluated at base line according to: Digital Rectal Examination (DRE), prostate volume, Post-Voided volume (PVR), International Prostate Symptoms Score (I-PSS), International Index of Erectile Function-5 (IIEF-5), Quality of Life (QoL), PSA values, urine analysis and urine culture, uroflowmetry. The same evaluation was conducted after a 12 month follow-up. ThuLEP was performed by 2 expert surgeons. Results Our data showed a better post-operative outcome in terms of catheter removal, blood loss, TURP syndrome, clot retention and residual tissue compared to large series of TURP and OP. Only 1.3% of patients had bladder wall injury during morcellation. I-PSS, Qmax, Prostate Volume, QoL and PVR showed a highly significant improvement at 12 month follow-up in comparison to preoperative assessment. Conclusion ThuLEP represent an innovative option in patients with BPH. It is a size independent surgical endoscopic technique and it can be considered the real alternative, at this time, to TURP and even more to Open Prostatectomy for large prostate, with a complete removal of adenoma and with a low complication rate. PMID:23173611

  9. A comparative study of diode laser and plasmakinetic in transurethral enucleation of the prostate for treating large volume benign prostatic hyperplasia: a randomized clinical trial with 12-month follow-up.

    PubMed

    Wu, Gang; Hong, Zhe; Li, Chao; Bian, Cuidong; Huang, Shengsong; Wu, Denglong

    2016-05-01

    The objective of this study is to compare the efficacy and safety of diode laser enucleation of the prostate (DiLEP) with plasmakinetic enucleation of the prostate (PKEP) for symptomatic benign prostatic hyperplasia (BPH) patients with large prostate (volume > 80 ml). From January 2013 to June 2014, 80 consecutive patients were randomized treated with DiLEP (n = 40) or PKEP (n = 40). Perioperative and postoperative outcome data were assessed during a 1-year follow-up. There were no significant preoperative differences between the two surgical groups. The mean prostate volumes in the DiLEP and PKEP groups were 98.6 and 93.3 ml, respectively. DiLEP was equivalent to PKEP in improvement in International Prostate Symptom Score (IPSS), quality of life scores, and maximum flow rate. Compared with PKEP, patients treated with DiLEP showed a lower risk of blood loss (P < 0.01), shorter bladder irrigation and catheterization times (P < 0.01), as well as shorter hospital stays (P < 0.01). Moreover, the DiLEP group was significantly superior to bipolar plasmakinetic group in the irritative symptoms. However, the operation time of the DiLEP group was longer than that of PKEP group (P = 0.02). Both DiLEP and PKEP are safe and effective methods for the treatment of BPH in large prostates (volume > 80 ml). Compared with PKEP, DiLEP provides a decreased risk of hemorrhage, reduced bladder irrigation, and catheterization times, as well as shorter hospital stays. PMID:26822403

  10. Calcium Signaling Is Required for Erythroid Enucleation

    PubMed Central

    Russell, Sarah M.; Humbert, Patrick O.

    2016-01-01

    Although erythroid enucleation, the property of erythroblasts to expel their nucleus, has been known for 7ore than a century, surprisingly little is known regarding the molecular mechanisms governing this unique developmental process. Here we show that similar to cytokinesis, nuclear extrusion requires intracellular calcium signaling and signal transduction through the calmodulin (CaM) pathway. However, in contrast to cytokinesis we found that orthochromatic erythroblasts require uptake of extracellular calcium to enucleate. Together these functional studies highlight a critical role for calcium signaling in the regulation of erythroid enucleation. PMID:26731108

  11. Calcium Signaling Is Required for Erythroid Enucleation.

    PubMed

    Wölwer, Christina B; Pase, Luke B; Russell, Sarah M; Humbert, Patrick O

    2016-01-01

    Although erythroid enucleation, the property of erythroblasts to expel their nucleus, has been known for 7ore than a century, surprisingly little is known regarding the molecular mechanisms governing this unique developmental process. Here we show that similar to cytokinesis, nuclear extrusion requires intracellular calcium signaling and signal transduction through the calmodulin (CaM) pathway. However, in contrast to cytokinesis we found that orthochromatic erythroblasts require uptake of extracellular calcium to enucleate. Together these functional studies highlight a critical role for calcium signaling in the regulation of erythroid enucleation. PMID:26731108

  12. Investigation and visualization of scleral channels created with femtosecond laser in enucleated human eyes using 3D optical coherence tomography images

    NASA Astrophysics Data System (ADS)

    Chaudhary, Gautam; Rao, Bin; Chai, Dongyul; Chen, Zhongping; Juhasz, Tibor

    2007-02-01

    We used optical coherence tomography (OCT) for non-invasive imaging of the anterior segment of the eye for investigating partial-thickness scleral channels created with a femtosecond laser. Glaucoma is associated with elevated intraocular pressure (IOP) due to reduced outflow facility in the eye. A partial-thickness aqueous humor (AH) drainage channel in the sclera was created with 1.7-μm wavelength femtosecond laser pulses to reduce IOP by increasing the outflow facility, as a solution to retard the progression of glaucoma. It is hypothesized that the precise dimensions and predetermined location of the channel would provide a controlled increase of the outflow rate resulting in IOP reduction. Therefore, it is significant to create the channel at the exact location with predefined dimensions. The aim of this research has two aspects. First, as the drainage channel is subsurface, it is a challenging task to determine its precise location, shape and dimensions, and it becomes very important to investigate the channel attributes after the laser treatment without disturbing the internal anterior structures. Second, to provide a non-invasive, image-based verification that extremely accurate and non-scarring AH drainage channel can be created with femtosecond laser. Partial-thickness scleral channels created in five human cadaver eyes were investigated non-invasively with a 1310-nm time-domain OCT imaging system. Three-dimensional (3D) OCT image stacks of the triangular cornea-sclera junction, also known as anterior chamber angle, were acquired for image-based analysis and visualization. The volumetric cutting-plane approach allowed reconstruction of images at any cross-sectional position in the entire 3D volume of tissue, making it a valuable tool for exploring and evaluating the location, shape and dimension of the channel from all directions. As a two-dimensional image-based methodology, an image-processing pipeline was implemented to enhance the channel features to

  13. One day surgery in the treatment of benign prostatic enlargement with thulium laser: A single institution experience

    PubMed Central

    Carmignani, Luca; Macchi, Alberto; Ratti, Dario; Finkelberg, Elisabetta; Casellato, Stefano; Maruccia, Serena; Marenghi, Carlo

    2015-01-01

    Purpose Various articles have previously addressed the introduction of new surgical laser therapies for an enlarged prostate gland causing obstructive symptoms. The objective of this study was to report the feasibility of performing the thulium laser vapo-enucleation of the prostate (ThuVEP) procedure for benign prostatic obstruction in a 1-day surgery. Materials and Methods From September 2011 to September 2013, we conducted a prospective study on patients who underwent ThuVEP in a 1-day surgery. The primary outcomes measured perioperatively included operative time, resected tissue weight, hemoglobin decrease, transfusion rate, postoperative irrigation and catheterization time, and postoperative hospital stay. Also, the preoperative and postoperative International Prostate Symptom Score (IPSS) and results of uroflowmetry performed on the 7th and 30th postoperative days were recorded. All perioperative and postoperative complications were monitored. Results A total of 53 patients underwent the surgical treatment in a 1-day surgery. Seven patients continued antiaggregant therapy with aspirin. Mean preoperative prostatic adenoma volume was 56.6 mL. Mean operative time was 71 minutes. The average catheter time was 14.8 hours. The peak urinary flow rate on day 7 improved from 9.3 to 17.42 mL/s (p<0.001) and the IPSS improved from 18 to 10.2 (p<0.01). Patients were routinely discharged on the day of catheter removal. No complications were recorded. Conclusions ThuVEP can be safely conducted as a 1-day surgical procedure. This strategy results in cost savings. ThuVEP shows good standardized outcomes with respect to improvement in flow parameters and length of bladder catheterization. PMID:25964837

  14. Enucleation in psychosis associated with aqueductal stenosis.

    PubMed

    Mancinelli, Iginia; Pompili, Maurizio; Scapati, Francesco; Lazanio, Simone; Kotzalidis, Giorgio D; Tatarelli, Roberto

    2004-03-01

    Reports of self-enucleation are frequent in medical literature, but cases of enucleation towards another are rare. We report the case of a man, 20 years of age, who suffered from psychosis with hydrocephalus and aqueductal stenosis that required a forensic psychiatric investigation to ascertain whether he was of unsound mind when he assaulted and enucleated the right eye of an officer and led to the surgical enucleation of the victim's left eye. Based on his clinical interviews and hospitalization record, we conclude that at the time of the assault, he was suffering from a delusional disorder with religious and demonic content, visual and auditory hallucinations, illusion phenomena, delusional interpretations, imaginative elements, a feeling of terror, and command hallucinations that compelled him to perform the act of aggression. PMID:15027561

  15. Enucleation versus plaque irradiation for choroidal melanoma

    SciTech Connect

    Straatsma, B.R.; Fine, S.L.; Earle, J.D.; Hawkins, B.S.; Diener-West, M.; McLaughlin, J.A.

    1988-07-01

    The Collaborative Ocular Melanoma Study (COMS) is an international, multicenter-controlled study. The organization includes an Executive Committee, Steering Committee, 6 Central Units, 32 Clinical Centers, and a Data and Safety Monitoring Committee. Scientifically, the COMS consists of (1) a randomized trial of patients with medium choroidal melanoma treated with enucleation versus iodine-125 plaque irradiation, (2) a randomized trial of patients with large choroidal melanoma treated with enucleation versus preenucleation external beam irradiation and enucleation, and (3) a prospective observational study of patients with small choroidal melanoma to determine whether a randomized trial of treatment is appropriate. In design and conduct of the COMS, special consideration is given to biostatistics and sample size considerations, iodine-125 plaque irradiation of choroidal melanoma, and coordinated ocular melanoma research. Recruitment is in progress. However, the pool of eligible patients is limited and the COMS needs the continued support and cooperation of ophthalmologists throughout the United States and Canada.

  16. Enucleation for Treating Rodent Ocular Disease

    PubMed Central

    Wilding, Laura A; Uchihashi, Mayu; Bergin, Ingrid L; Nowland, Megan H

    2015-01-01

    Our standard of care for rodent corneal lesions previously included treatment of the primary lesion, application of topical NSAIDs, and systemic NSAIDs in severe cases. When intensive medical management was unsuccessful, animals were euthanized, leading to premature loss of valuable genetically modified animals and those on long-term studies. We investigated enucleation surgery as a treatment for 15 cases of rodent corneal disease that did not respond to medical management. Enucleation was performed under isoflurane anesthesia and involved removal of the globe, extensive hemostasis, and packing the orbital space with absorbable gelatin sponge. The lid margins were closed by tarsorrhaphy and tissue glue. Analgesia was provided by using buprenorphine preoperatively and carprofen chew tabs postoperatively. To date, we have a 100% success rate with this procedure (n = 20; 15 clinically affected rodents [2 rats, 13 mice], 5 healthy controls), which included a 60-d follow-up period. The single complication involved dehiscence of the tarsorrhaphy site and was repaired by trimming the lid margins to provide fresh tissue for closure. Histologic examination at both 1 and 3 mo after surgery revealed no evidence of infection of the enucleation site. Enucleation in rodents is a straightforward procedure that represents a refinement to our current standard of care for rodents, does not cause significant inflammation of remaining periocular structures, and has reduced the number of animals euthanized prior to study endpoint because of severe ocular lesions. PMID:26045460

  17. [Testicular epidermoid cyst: orchiectomy or enucleation resection?].

    PubMed

    Heidenreich, A; Zumbé, J; Vorreuther, R; Klotz, T; Vietsch, H; Engelmann, U H

    1996-01-01

    Our experience with 18 patients with simple epidermoid cysts of the testis is reported. In each patient the tumour was enucleated completely and two biopsies of the adjacent parenchyma were obtained for exclusion of associated germ cell cancer, scars or carcinoma in situ. There was no evidence of malignancy in any of the biopsy specimens. Preoperative evaluation included physical examination, testicular sonography, and determination of AFP and hCG serum levels. Although epidermoid cyst can be strongly suspected on sonography the ultrasound appearance is not specific, and inguinal testicular exploration was required in these patients. In 1 patient multiple epidermoid cysts of the right testis were associated with an adult teratoma containing embryonal carcinoma and choriocarcinoma of the left testis; no similar case has been described in the literature. On the basis of our results and experience we consider tumour enucleation and biopsy of the adjacent parenchyma to be adequate treatment for benign epidermoid cyst. The world literature concerning organ-sparing surgery in testicular epidermoid cyst is reviewed. PMID:8851841

  18. Erythroblast enucleation is a dynein-dependent process.

    PubMed

    Kobayashi, Isuzu; Ubukawa, Kumi; Sugawara, Kotomi; Asanuma, Ken; Guo, Yong-Mei; Yamashita, Junsuke; Takahashi, Naoto; Sawada, Kenichi; Nunomura, Wataru

    2016-04-01

    Mammalian erythroblasts undergo enucleation through a process thought to be similar to cytokinesis. Microtubule-organizing centers (MTOCs) mediate organization of the mitotic spindle apparatus that separates the chromosomes during mitosis and are known to be crucial for proper cytokinesis. However, the role of MTOCs in erythroblast enucleation remains unknown. We therefore investigated the effect of various MTOC inhibitors on cytokinesis and enucleation using human colony-forming units-erythroid (CFU-Es) and mature erythroblasts generated from purified CD34(+) cells. We found that erythro-9-[3-(2-hydroxynonyl)]adenine (EHNA), a dynein inhibitor, and monastrol, a kinesin Eg5 inhibitor, as well as various inhibitors of MTOC regulators, including ON-01910 (Plk-1), MLN8237 (aurora A), hesperadin (aurora B), and LY294002 (PI3K), all inhibited CFU-E cytokinesis. Among these inhibitors, however, only EHNA blocked enucleation. Moreover, terminally differentiated erythroblasts expressed only dynein; little or none of the other tested proteins was detected. Over the course of the terminal differentiation of human erythroblasts, the fraction of cells with nuclei at the cell center declined, whereas the fraction of polarized cells, with nuclei shifted to a position near the plasma membrane, increased. Dynein inhibition impaired nuclear polarization, thereby blocking enucleation. These data indicate that dynein plays an essential role not only in cytokinesis but also in enucleation. We therefore conclude that human erythroblast enucleation is a process largely independent of MTOCs, but dependent on dynein. PMID:26724640

  19. Unsuccessful Self-Enucleation in a Schizophrenic Patient

    PubMed Central

    Noy Achiron, Romi; Paul, Michael; Achiron, Asaf

    2014-01-01

    Self-enucleation is a very unusual form of self-mutilation directly linked to mental illness. In this case we present a 26-year-old schizophrenic patient who attempted to enucleate his eye with a rollerball pen. Antipsychotic therapy and emergency surgery saved the patient eye and emphasize the importance of quick response and good collaboration between psychiatric and ophthalmic teams. PMID:25328735

  20. On-chip enucleation of an oocyte by untethered microrobots

    NASA Astrophysics Data System (ADS)

    Ichikawa, Akihiko; Sakuma, Shinya; Sugita, Masakuni; Shoda, Tatsuro; Tamakoshi, Takahiro; Akagi, Satoshi; Arai, Fumihito

    2014-09-01

    We propose a novel on-chip enucleation of an oocyte with zona pellucida by using a combination of untethered microrobots. To achieve enucleation within the closed space of a microfluidic chip, two microrobots, a microknife and a microgripper were integrated into the microfluidic chip. These microrobots were actuated by an external magnetic force produced by permanent magnets placed on the robotic stage. The tip of the microknife was designed by considering the biological geometric feature of an oocyte, i.e. the oocyte has a polar body in maturation stage II. Moreover, the microknife was fabricated by using grayscale lithography, which allows fabrication of three-dimensional microstructures. The microgripper has a gripping function that is independent of the driving mechanism. On-chip enucleation was demonstrated, and the enucleated oocytes are spherical, indicating that the cell membrane of the oocytes remained intact. To confirm successful enucleation using this method, we investigated the viability of oocytes after enucleation. The results show that the production rate, i.e. the ratio between the number of oocytes that reach the blastocyst stage and the number of bovine oocytes after nucleus transfer, is 100%. The technique will contribute to complex cell manipulation such as cell surgery in lab-on-a-chip devices.

  1. Risk factors for endophthalmitis requiring evisceration or enucleation

    PubMed Central

    Lu, Xuehui; Ng, Danny Siu-Chun; Zheng, Kangkeng; Peng, Kun; Jin, Chuang; Xia, Honghe; Chen, Weiqi; Chen, Haoyu

    2016-01-01

    Endophthalmitis has devastating sequelae resulting in blindness and even loss of eyeball. Although the prognosis of endophthalmitis has much improved with the advances of antibiotics and vitreoretinal surgery, of the number of patients that required evisceration or enucleation is still significant. We retrospectively reviewed the charts of 210 eyes of 210 patients with endophthalmitis andcompared the group that required evisceration or enucleation with those that received salvaging therapies. Regression analysis was used to identify the risk factors for evisceration or enucleation. Thirty eyes (14.3%) underwent enucleation or evisceration. The group of eviscerated or enucleated eyes were older (58.7 vs. 42.2 years, p < 0.001), had more women (56.7% vs. 22.2%, p = 0.003), had poorer initial visual acuity (2.79 vs. 2.10 LogMAR, p < 0.001), and had longer duration before intervention (18.03 vs. 5.74 days, p = 0.031). The most common primary indications for endophthalmitis were infections from corneal ulcer (50.0% vs. 4.4%, p < 0.001) andfrom endogenous source (23.3% vs. 5.6%, p < 0.001). Less common indications were trauma (26.7% vs. 67.8%, p < 0.001) and postoperative (6.7% vs. 22.2%, p = 0.049) endophthalmitis. After adjusting for confounding factors, corneal ulcer-related endophthalmitis, endogenous endophthalmitis and initial visual acuity were the independent risk factors for evisceration or enucleation. PMID:27302573

  2. Psychological Reactions and Persistent Facial Pain following Enucleation

    PubMed Central

    2014-01-01

    Background. Enucleation is a psychologically and physically traumatic event associated with chronic pain. It would be desirable to better predict which patients will have pain after surgery. Methods. A cross-sectional postal questionnaire study of adults undergoing enucleation captured the demographic details, Pain Quality Assessment Scale (PQAS), Pain Catastrophizing Scale (PCS), and the Facial Pain Assessment questionnaire. Patients were classified as suffering from chronic pain if they reported a pain score of >1 out of 10 on the numerical pain score (NRS). Results. Seventeen of 60 adults participated in the study. 47% of patients reported chronic pain (mean pain score = 1.4 ± 0.7, n = 17); 25% experienced pain daily. No difference in age, surgical side, reason for surgery, or the duration of time since the surgery was noted. All patients had low PQAS scores and 50% of individuals with persistent pain were concerned about their facial appearance. There was no significant difference in the level of catastrophization noted in patients with or without pain or between the subgroups (rumination, magnification, or helplessness). Conclusions. Although persistent pain following enucleation affected a significant number of patients, the pain intensity was mild. Enucleation influenced the physical perception some individuals had of themselves. PMID:24864208

  3. Difficulty in the intravesical morcellation procedure for leiomyoma of the prostate enucleated by HoLEP.

    PubMed

    Shinojima, Toshiaki; Yoshimine, Shunsuke

    2013-01-01

    Leiomyoma of prostate are rare benign neoplasms that are usually diagnosed incidentally through postoperative pathological examination. A 70-year-old man is presented with severe symptoms of lower urinary tract obstruction. Although a digital rectal examination and the prostate-specific antigen level did not suggest malignancy, transrectal ultrasonography showed an unusual homogenous echoic mass measuring 45×37 mm in size in the prostate. A needle biopsy was performed and pathological diagnosis was prostatic leiomyoma. Holmium laser enucleation of prostate (HoLEP) was chosen and performed to resect the tumour. Although the enucleation step presented no problems, the morcellation procedure using a conventional transurethral mechanical morcellator was very difficult owing to the firmness of the tissue. By using a bipolar erectrosurgical loop, fragmentation and removal of tissue was accomplished. This is the first case reported of these rare neoplasms in which HoLEP was offered as a less invasive surgical approach. We emphasise the firmness of the leiomyomatous tissue, which would lead to morcellation failure. PMID:23966460

  4. Difficulty in the intravesical morcellation procedure for leiomyoma of the prostate enucleated by HoLEP

    PubMed Central

    Shinojima, Toshiaki; Yoshimine, Shunsuke

    2013-01-01

    Leiomyoma of prostate are rare benign neoplasms that are usually diagnosed incidentally through postoperative pathological examination. A 70-year-old man is presented with severe symptoms of lower urinary tract obstruction. Although a digital rectal examination and the prostate-specific antigen level did not suggest malignancy, transrectal ultrasonography showed an unusual homogenous echoic mass measuring 45×37 mm in size in the prostate. A needle biopsy was performed and pathological diagnosis was prostatic leiomyoma. Holmium laser enucleation of prostate (HoLEP) was chosen and performed to resect the tumour. Although the enucleation step presented no problems, the morcellation procedure using a conventional transurethral mechanical morcellator was very difficult owing to the firmness of the tissue. By using a bipolar erectrosurgical loop, fragmentation and removal of tissue was accomplished. This is the first case reported of these rare neoplasms in which HoLEP was offered as a less invasive surgical approach. We emphasise the firmness of the leiomyomatous tissue, which would lead to morcellation failure. PMID:23966460

  5. The risk of enucleation after proton beam irradiation of uveal melanoma

    SciTech Connect

    Egan, K.M.; Gragoudas, E.S.; Seddon, J.M.; Glynn, R.J.; Munzenreider, J.E.; Goitein, M.; Verhey, L.; Urie, M.; Koehler, A. )

    1989-09-01

    Enucleation after proton beam irradiation of uveal melanomas occurred in 64 (6.4%) of 994 eyes with a median follow-up time of 2.7 years. The median time between irradiation and enucleation in the 64 enucleated eyes was 13 months. The probability of retaining the eye was 95 and 90%, 2 and 5 years postirradiation, respectively. Three percent of eyes were enucleated during posttreatment year 1, and the yearly rate was 1% by the fourth year. No patient had enucleation later than 5 1/2 years posttreatment. The complication most likely to result in enucleation was neovascular glaucoma although this was frequently managed without enucleation. Other common reasons for enucleation were documented or suspected tumor growth and complete retinal detachment with associated loss of vision. The leading risk factors for enucleation were anterior tumor margin involving the ciliary body, tumor height greater than 8 mm, and proximity of the tumor to the fovea. Based on the presence or absence of these factors, 5-year eye retention rates were 99, 92, and 76% for low-, moderate-, and high-risk groups, respectively. Thus, the probability of eye retention after proton beam irradiation is high even among those at greatest risk of enucleation.

  6. Cobalt-60 plaque radiotherapy vs enucleation for posterior uveal melanoma

    SciTech Connect

    Augsburger, J.J.; Gamel, J.W.; Lauritzen, K.; Brady, L.W. )

    1990-05-15

    We compared the survival of 302 patients with a primary choroidal or ciliary body melanoma treated by cobalt-60 plaque radiotherapy between 1976 and 1982 with the survival of 134 patients treated by enucleation during the same period. Tumor size, location of the anterior margin of the tumor, and patient age at the time of treatment were identified as simultaneous significant clinical variables for predicting melanoma-specific mortality by multivariate Cox proportional hazards modeling. We computed a prognostic index for each patient based on this model and found that patients in the enucleation group had slightly higher values of this index than did patients in the cobalt-60 plaque radiotherapy group. Risk ratios for the treatment effect computed from a Cox model incorporating prognostic index and the treatment variable were found to be approximately equal to 1, both for analysis of melanoma-specific mortality and total mortality. These results indicate that when one controls for differences in prognostic index between the groups, cobalt-60 plaque therapy and enucleation are essentially equivalent in their effect on survival.

  7. Phylogenic insights into the enucleation of erythroblasts in human.

    PubMed

    Nunomura, Wataru

    2016-07-01

    Two key questions remain unanswered in the erythropoiesis field: Why and how do erythroblasts enucleate in mammalian species? Recent studies have unveiled the roles of various molecules, cytoskeletal proteins, motor proteins, vesicle transport, signaling pathways, lipid rafts and actomyosin ring contraction in the enucleation process. However, few reports provide insights into the fitness benefit for mammalian species of having anucleate erythrocytes. Herein, we discuss the biological significance of enucleation of human erythroblasts based on our recent results and on evolutionary considerations related to the biology of hemoglobin and the comparative biochemistry of erythrocyte membrane cytoskeletal proteins, such as protein 4.1R. We specifically focus on the Mesozoic era, a geological period during which dinosaurs and the ancestors of mammalian species coexisted. Approximately 200 million years ago, at the beginning of this era, the earth's atmosphere was hypoxic. Interestingly, animals adopted different respiration systems to adapt to this hypoxic environment. Recent studies using state-of-the-art technologies have shown that dinosaurs might have had nucleated erythrocytes. After dinosaurs became extinct about 65.5 million years ago, their respiration system was maintained by birds. We propose a new adaptive theory that establishes a correlation between evolution towards nucleated or anucleate erythrocytes depending on organism respiration systems during the Mesozoic era. PMID:27498741

  8. Enucleation: a possible mechanism of cancer cell death

    PubMed Central

    Paunescu, Virgil; Bojin, Florina M; Gavriliuc, Oana I; Taculescu, Elena A; Ianos, Robert; Ordodi, Valentin L; Iman, Vlad F; Tatu, Calin A

    2014-01-01

    There are few major morphologies of cell death that have been described so far: apoptosis (type I), cell death associated with autophagy (type II), necrosis (type III) and anchorage-dependent mechanisms—anoikis. Here, we show for the first time a possibly novel mechanism inducing tumour cell death under in vitro conditions—enucleation. We pursued the influence of colloidal suspensions of Fe3O4 nanoparticles on tumour cell lines (SK-BR-3 and MCF-7 breast cancer cell lines) grown according to standard cell culture protocols. Magnetite nanoparticles were prepared by combustion synthesis and double layer coated with oleic acid. Scanning and transmission electron microscopy revealed that tumour cells developed a network of intracytoplasmic stress fibres, which induce extrusion of nuclei, and enucleated cells die. Normal adult mesenchymal stem cells, used as control, did not exhibit the same behaviour. Intact nuclei were found in culture supernatant of tumour cells, and were visualized by immunofluorescence. Enucleation as a potential mechanism of tumour cell death might open new horizons in cancer biology research and development of therapeutic agents capable of exploiting this behaviour. PMID:24629135

  9. Sequential transurethral enucleation of the prostate and laparoscopic bladder diverticulectomy.

    PubMed

    Yu, Yang; Guan, Sheng; Shen, Chen; Yang, Bo

    2016-08-01

    Transurethral endoscopic technique and standard laparoscopic technique are surgical options for the management of benign prostatic hyperplasia (BPH) associated with urinary bladder diverticuli (UBD). In this article, we report laparoscopic diverticulectomy (LD) and transurethral plasmakinetic enucleation of the prostate (TUEP) in the same patient sequentially. To the best of our knowledge, this is the first case report of LD combined with TUEP. An 82-year-old patient with benign prostatic hyperplasia and two secondary large bladder diverticuli underwent sequential TUEP and LD. After completion of the TUEP procedure, the detached adenoma was pushed into the bladder as a whole. Then laparoscopic transperitoneal extravesical diverticulectomy assisted by cystoscopic transillumination was performed immediately, and the enucleated prostate was removed via the neck of the diverticulum. The enucleation time and diverticulectomy time was 18 minutes and 108 minutes, respectively. The catheter was removed on the tenth postoperative day. Transurethral endoscopic surgery combined with LD is a good choice in treating BPH and UBD in one session. But the combined procedure is time-consuming, especially for fragmentation of the prostate. TUEP can greatly reduce the operative time of the combined procedure. PMID:27249185

  10. Self-enucleation: forget Freud and Oedipus, it's all about untreated psychosis.

    PubMed

    Large, Matthew Michael; Nielssen, Olav B

    2012-08-01

    Self-enucleation is a rare but serious ophthalmological and psychiatric emergency. It has traditionally been considered to be the result of psycho-sexual conflicts, including those arising from Freud's Oedipal complex and Christian religious teaching. However, an analysis of published case reports suggests that self-enucleation is a result of psychotic illnesses such as schizophrenia. Early treatment with antipsychotic medication in the case of unilateral or threatened self-enucleation might prevent some cases of blindness. PMID:22373824

  11. The construction of cloned Sika deer embryos (Cervus nippon hortulorum) by demecolcine auxiliary enucleation.

    PubMed

    Yin, Y; Mei, M; Zhang, D; Zhang, S; Fan, A; Zhou, H; Li, Z

    2014-02-01

    The objective of our study was to establish the feasibility of experimental protocols for cloning sika deer. We performed auxiliary enucleation to improve the efficiency of nuclear transfer operation by optimizing the demecolcine concentration to induce cytoplasmic protrusions in the sika deer oocytes. In the present study,we had studied the impact of different demecolcine concentrations on cytoplasmic protrusions and enucleation rates. We determined that 95.9% of the sika deer oocytes formed cytoplasmic protrusions when treated for 1 h with 0.8 μg/ml demecolcine. The lowest observed rate of protrusion was 19.3% after overnight treatment with demecolcine. When the oocytes aged or had a poor cumulus expansion, they exhibited a significant decrease in the ability to form cytoplasmic protrusions. The rates of enucleation (94.9% vs 85.8%, p < 0.05), cell fusion (84.6% vs 70.1%, p < 0.05) and blastocyst formation (15.4% vs 10.9%, p < 0.05) using demecolcine auxiliary enucleation were significantly higher than those after blind enucleation. These results demonstrated that sika deer oocytes could be enucleated quickly and effectively using demecolcine auxiliary enucleation, which could enhance the enucleation rate, cell fusion rate and blastocyst rate of cloned embryos in vitro. PMID:24138424

  12. Endoscope-Assisted Enucleation of Mandibular Odontogenic Keratocyst Tumors.

    PubMed

    Romano, Antonio; Orabona, Giovanni D A; Abbate, Vincenzo; Maglitto, Fabio; Solari, Domenico; Iaconetta, Giorgio; Califano, Luigi

    2016-09-01

    The keratocyst odontogenic tumor (KCOT) represents a rare and benign but locally aggressive developmental cystic lesion usually affecting the posterior aspect of the mandible bone, the treatment of which has always been raising debate, since Philipsen first described it as a distinct pathological entity in 1956.Recent studies have proposed the use of endoscope-assisted surgical technique, due to the possibility given by the endoscope of improving the effectiveness of the treatment of these lesions thanks to a better visualization of operative field and though a better understanding of the pathology. In this article, we would like to present our experience with the endoscope-assisted treatment of KCOT of the posterior region of the mandible.From April 2000 to April 2012, 32 patients treated for KCOT were enrolled in our retrospective study: patients were divided in 2 groups according to the type of treatment, that is, 18 were treated with traditional enucleation surgery (TES), and 14 patients underwent endoscopic assisted enucleation surgery (EES).Fischer exact test and Kaplan-Meier curves were used to compare the outcomes between the 2 focusing on the recurrence and complication rates. In the TES group, patients we found a higher recurrence rate (39%) and higher postoperative complication rate at 5-year follow-up.Our data suggested, though, that EES seems to be a feasible alternative for the treatment of posterior mandibular KCOT. Further studies and larger series are needed to confirm these results. PMID:27607111

  13. Unsuspected Ganglioneuroma of the Choroid Diagnosed after Enucleation

    PubMed Central

    Mbagwu, Michael; Rahmani, Bahram; Srivastava, Arth; Burrowes, Delilah; Bryar, Paul J.

    2015-01-01

    We report a case of an unsuspected ganglioneuroma of the choroid in a patient with neurofibromatosis type 1. A 5-year-old girl presented from an outside institution with right proptosis and glaucoma since birth. Magnetic resonance imaging was obtained and showed a cavernous sinus mass extending into the right orbit and multiple orbital lesions. Additionally, increased signal in the posterior globe of the right eye was noted, but its etiology was unclear at the time. She was lost to follow-up for 3 years and later returned with a blind painful eye. Enucleation was performed, and histopathology was significant for diffuse choroidal ganglioneuroma and advanced glaucoma. We report the atypical history, examination findings, and histopathology to support the diagnosis. PMID:27171204

  14. Enucleation and development of cluster headache: a retrospective study

    PubMed Central

    Sörös, Peter; Vo, Oanh; Gerding, Heinrich; Husstedt, Ingo W; Evers, Stefan

    2005-01-01

    Background Cluster headache (CH) is a neurovascular, primary headache disorder. There are, however, several case reports about patients whose CH started shortly after a structural brain disease or trauma. Motivated by a patient who developed CH 3 weeks after the removal of an eye and by similar case reports, we tested the hypothesis that the removal of an eye is a risk factor for CH. Methods A detailed headache questionnaire was filled out by 112 patients on average 8 years after enucleation or evisceration of an eye. Results While 21 % of these patients experienced previously unknown headaches after the removal of an eye, no patient fulfilled the diagnostic criteria for CH. Conclusion Our data does not suggest that the removal of an eye is a major risk factor for the development of CH. PMID:15784136

  15. The eyeball killer: serial killings with postmortem globe enucleation.

    PubMed

    Coyle, Julie; Ross, Karen F; Barnard, Jeffrey J; Peacock, Elizabeth; Linch, Charles A; Prahlow, Joseph A

    2015-05-01

    Although serial killings are relatively rare, they can be the cause of a great deal of anxiety while the killer remains at-large. Despite the fact that the motivations for serial killings are typically quite complex, the psychological analysis of a serial killer can provide valuable insight into how and why certain individuals become serial killers. Such knowledge may be instrumental in preventing future serial killings or in solving ongoing cases. In certain serial killings, the various incidents have a variety of similar features. Identification of similarities between separate homicidal incidents is necessary to recognize that a serial killer may be actively killing. In this report, the authors present a group of serial killings involving three prostitutes who were shot to death over a 3-month period. Scene and autopsy findings, including the unusual finding of postmortem enucleation of the eyes, led investigators to recognize the serial nature of the homicides. PMID:25682709

  16. Symptomatic subserosal gastric lipoma successfully treated with enucleation

    PubMed Central

    Krasniqi, Avdyl Selmon; Hoxha, Faton Tatil; Bicaj, Besnik Xhafer; Hashani, Shemsedin Isuf; Hasimja, Shpresa Mehmet; Kelmendi, Sadik Mal; Gashi-Luci, Lumturije Hasan

    2008-01-01

    Gastric lipomas are rare tumors, accounting for 2%-3% of all benign gastric tumors. They are of submucosal or extremely rare subserosal origin. Although most gastric lipomas are usually detected incidentally, they can cause abdominal pain, dyspeptic disorders, obstruction, invagination, and hemorrhages. Subserosal gastric lipomas are rarely symptomatic. There is no report on treatment of subserosal gastric lipomas in the English literature. We present a case of a 50-year-old male with symptomatic subserosal gastric lipoma which was successfully managed with removal, enucleation of lipoma, explorative gastrotomy and edge resection for histology check of gastric wall. The incidence of gastric lipoma, advanced diagnostic possibilities and their role in treatment modalities are discussed. PMID:18855998

  17. Effect of the method of enucleation on the prognosis of choroidal melanoma.

    PubMed Central

    Migdal, C

    1983-01-01

    The prognosis following treatment of uveal melanomata depends not only on factors such as cell type and degree of mitotic activity, size and location of the tumour, and the age of the patient, but also on the method of enucleation, as surgical manipulation of the neoplasm may potentiate the shedding of malignant cells into the blood stream. One hundred and thirty-one patients treated by different methods of enucleation were reviewed and the mortality patterns assessed. The numbers of deaths over the first 5 years differed significantly between the different groups. A specific method of enucleation used for tumour-containing eyes is described and its importance emphasised. Images PMID:6849859

  18. Attempted auto-enucleation in two incarcerated young men with psychosis

    PubMed Central

    Reichstein, David; Esmaili, Neda; Wells, Timothy; Kim, Judy E.

    2014-01-01

    Auto-enucleation is a sign of untreated psychosis. We describe two patients who presented with attempted auto-enucleation while being incarcerated. This is an observation two-case series of two young men who suffered untreated psychosis while being incarcerated. These young men showed severe self-inflicted ocular trauma during episodes of untreated psychosis. Injuries included orbital bone fracture and dehiscence of the lateral rectus in one patient and severe retinal hemorrhage and partial optic nerve avulsion in the second patient. Auto-enucleation is a severe symptom of untreated psychosis. This urgent finding can occur in a jail setting in which psychiatric care may be minimal. PMID:25892940

  19. Attempted auto-enucleation in two incarcerated young men with psychosis.

    PubMed

    Reichstein, David; Esmaili, Neda; Wells, Timothy; Kim, Judy E

    2015-01-01

    Auto-enucleation is a sign of untreated psychosis. We describe two patients who presented with attempted auto-enucleation while being incarcerated. This is an observation two-case series of two young men who suffered untreated psychosis while being incarcerated. These young men showed severe self-inflicted ocular trauma during episodes of untreated psychosis. Injuries included orbital bone fracture and dehiscence of the lateral rectus in one patient and severe retinal hemorrhage and partial optic nerve avulsion in the second patient. Auto-enucleation is a severe symptom of untreated psychosis. This urgent finding can occur in a jail setting in which psychiatric care may be minimal. PMID:25892940

  20. Decompression, enucleation, and implant placement in the management of a large dentigerous cyst.

    PubMed

    Cakarer, Sirmahan; Selvi, Firat; Isler, Sabri Cemil; Keskin, Cengizhan

    2011-05-01

    The dentigerous cyst is a developmental odontogenic cyst, accounting for 10% of all cysts of the jaws. The treatment options are decompression, marsupialization, or enucleation regarding the features of the lesions. In this article, a case of a 17-year-old adolescent girl having a large mandibular dentigerous cyst associated with an unerupted third molar is presented. The treatment is composed of decompression for 6 months and enucleation. Decompression and enucleation are a predictable choice in the treatment of large cysts. Radiologic evaluation is mandatory to decide for the appropriate time for the removal of the decompression stents, the enucleation time, and also for the evaluation of the adequate new bone formation for implant placement. The present case emphasizes the success of a conservative approach in the management of a large dentigerous cyst in a young patient and also the maintenance of the new bone formation without using any graft materials for the placement of dental implants. PMID:21558915

  1. Prosthetic rehabilitation of an ocular defect with post-enucleation socket syndrome: A case report

    PubMed Central

    Amornvit, Pokpong; Rokaya, Dinesh; Shrestha, Binit; Srithavaj, Theerathavaj

    2014-01-01

    Ocular trauma can be caused by road traffic accidents, falls, assaults, or work-related accidents. Enucleation is often indicated after ocular injury or for the treatment of intraocular tumors, severe ocular infections, and painful blind eyes. Rehabilitation of an enucleated socket without an intraocular implant or with an inappropriately sized implant can result in superior sulcus deepening, enophthalmos, ptosis, ectropion, and lower lid laxity, which are collectively known as post-enucleation socket syndrome. This clinical report describes the rehabilitation of post-enucleation socket syndrome with a modified ocular prosthesis. Modifications to the ocular prosthesis were performed to correct the ptosis, superior sulcus deepening, and enophthalmos. The rehabilitation procedure produced satisfactory results. PMID:24526826

  2. Mouse model of brachytherapy in consort with enucleation for treatment of malignant intraocular melanoma

    SciTech Connect

    Niederkorn, J.; Sanborn, G.E.; Scarbrough, E.E. )

    1990-06-01

    The efficacy of brachytherapy in the treatment and prevention of metastasis of intraocular melanoma was investigated in a mouse model. A highly metastatic subline of B16 melanoma was transplanted into the anterior segment of C57BL/6 mice and allowed to grow. Brachytherapy was delivered by means of miniature iodine 125 seeds implanted in shallow subcutaneous pockets of the upper eyelid margin of these mice, and 25 Gy of radiation was delivered between days 12 and 14. This brachytherapy reduced both the tumor volume and the number of mitotic figures per high-power field compared with irradiated controls. In a second experiment, 25 Gy of brachytherapy was delivered before enucleation, straddling enucleation, and after enucleation; there was a significant reduction in metastasis when radiation was delivered prior to enucleation. This model may be useful in conducting further studies involving brachytherapy with 125I plaque implants.

  3. Prosthetic rehabilitation of an ocular defect with post-enucleation socket syndrome: A case report.

    PubMed

    Amornvit, Pokpong; Rokaya, Dinesh; Shrestha, Binit; Srithavaj, Theerathavaj

    2014-01-01

    Ocular trauma can be caused by road traffic accidents, falls, assaults, or work-related accidents. Enucleation is often indicated after ocular injury or for the treatment of intraocular tumors, severe ocular infections, and painful blind eyes. Rehabilitation of an enucleated socket without an intraocular implant or with an inappropriately sized implant can result in superior sulcus deepening, enophthalmos, ptosis, ectropion, and lower lid laxity, which are collectively known as post-enucleation socket syndrome. This clinical report describes the rehabilitation of post-enucleation socket syndrome with a modified ocular prosthesis. Modifications to the ocular prosthesis were performed to correct the ptosis, superior sulcus deepening, and enophthalmos. The rehabilitation procedure produced satisfactory results. PMID:24526826

  4. Increased cortical surface area and gyrification following long-term survival from early monocular enucleation

    PubMed Central

    Kelly, Krista R.; DeSimone, Kevin D.; Gallie, Brenda L.; Steeves, Jennifer K.E.

    2014-01-01

    Purpose Retinoblastoma is typically diagnosed before 5 years of age and is often treated by enucleation (surgical removal) of the cancerous eye. Here, we sought to characterize morphological changes of the cortex following long-term survival from early monocular enucleation. Methods Nine adults with early right-eye enucleation (≤48 months of age) due to retinoblastoma were compared to 18 binocularly intact controls. Surface area, cortical thickness, and gyrification estimates were obtained from T1 weighted images and group differences were examined. Results Early monocular enucleation was associated with increased surface area and/or gyrification in visual (i.e., V1, inferior temporal), auditory (i.e., supramarginal), and multisensory (i.e., superior temporal, inferior parietal, superior parietal) cortices compared with controls. Visual cortex increases were restricted to the right hemisphere contralateral to the remaining eye, consistent with previous subcortical data showing asymmetrical lateral geniculate nucleus volume following early monocular enucleation. Conclusions Altered morphological development of visual, auditory, and multisensory regions occurs subsequent to long-time survival from early eye loss. PMID:25610793

  5. Enucleation vs cobalt plaque radiotherapy for malignant melanomas of the choroid and ciliary body

    SciTech Connect

    Augsburger, J.J.; Gamel, J.W.; Sardi, V.F.; Greenberg, R.A.; Shields, J.A.; Brady, L.W.

    1986-05-01

    Clinical risk factors were assessed prospectively in a nonrandomized concurrent observational study of 237 patients with posterior uveal malignant melanoma. One hundred forty of these patients were treated with enucleation, and 97 underwent cobalt plaque radiotherapy. Tumor size and location of the anterior tumor margin proved to be the most significant clinical risk factors for death from metastatic melanoma. When Cox proportional hazards modeling was used to adjust for recognized intergroup differences in risk factors, the effect of therapy (enucleation vs cobalt plaque radiotherapy) on survival time was not statistically significant. We discuss the implications of this study for a randomized clinical trial of enucleation vs cobalt plaque therapy or comparable forms of irradiation.

  6. Standard Enucleation with Aluminium Oxide Implant (Bioceramic) Covered with Patient's Sclera

    PubMed Central

    Zigiotti, Gian Luigi; Cavarretta, Sonia; Morara, Mariachiara; Nam, Sang Min; Ranno, Stefano; Pichi, Francesco; Lembo, Andrea; Lupo, Stefano; Nucci, Paolo; Meduri, Alessandro

    2012-01-01

    Purpose. We describe in our study a modified standard enucleation, using sclera harvested from the enucleated eye to cover the prosthesis in order to insert a large porous implant and to reduce postoperative complication rates in a phthisis globe. Methods. We perform initially a standard enucleation. The porous implant (Bioceramic) is then covered only partially by the patient's sclera. The implant is inserted in the posterior Tenon's space with the scleral covering looking at front. All patients were followed at least for twelve months (average followup 16 months). Results. We performed nineteen primary procedures (19 patients, 19 eyes, x M; x F) and secondary, to fill the orbital cavity in patients already operated by standard evisceration (7 patients, 7 eyes). There were no cases of implant extrusion. The orbital volume was well reintegrated. Conclusion. Our procedure was safe and effective. All patients had a good cosmetic result after final prosthetic fitting and we also achieved good prothesis mobility. PMID:22654614

  7. Video Assisted Thoracoscopic Surgical Enucleation of a Giant Esophageal Leiomyoma Presenting with Persistent Cough

    PubMed Central

    Mujawar, Parvez; Pawar, Tushar; Chavan, Rahulkumar Narayan

    2016-01-01

    Esophageal leiomyoma is a relatively rare tumor of esophagus but it is the most common benign neoplasm of the esophagus. Small esophageal leiomyoma can be observed but larger ones and those producing symptoms should be excised. As observed for other esophageal tumors, dysphagia is its main symptom. Traditionally, open thoracotomy and enucleation are its main treatment but in the last few years video assisted thoracoscopic surgical (VATS) enucleation is gaining recognition with proven advantages of minimally invasive surgery. Herein we present our experience with patient presenting with cough rather than dysphagia as a main symptom, who was diagnosed to be having giant esophageal leiomyoma. VATS guided enucleation was accomplished successfully. Size of lesion was 16 × 4 × 3 cm. Postoperative recovery was uneventful and patient is not having any signs of recurrence, after three years during follow-up period. PMID:26977331

  8. Enucleation of Eye Using Finger Following Cannabis Consumption: A Case Report

    PubMed Central

    Sabahi, Abdol Reza; Amini-Ranjbar, Zahra; Sharifi, Ali; Kheradmand, Ali

    2014-01-01

    Background Enucleation is a topic discussed in psychiatry which is a self-injury matter. Enucleation is observed as psychotic disorder due to substance abuse. In people with mental disorders who also have substance use leading to hallucinations and delusions, unusual eye evacuation were reported. In most cases, enucleation was done using sharp tools. Case Report This report describes a man suffering from psychosis after consuming hashish and has attempted to evacuate his eyes with his finger. Discussion Given the increasing prevalence of hashish use by young people, and false beliefs about the use of hashish in order to withdraw other substances, preventive methods and education for young and vulnerable people are suggested. PMID:25140221

  9. Rapid Changes in Cortical and Subcortical Brain Regions after Early Bilateral Enucleation in the Mouse

    PubMed Central

    Huffman, Kelly J.

    2015-01-01

    Functional sensory and motor areas in the developing mammalian neocortex are formed through a complex interaction of cortically intrinsic mechanisms, such as gene expression, and cortically extrinsic mechanisms such as those mediated by thalamic input from the senses. Both intrinsic and extrinsic mechanisms are believed to be involved in cortical patterning and the establishment of areal boundaries in early development; however, the nature of the interaction between intrinsic and extrinsic processes is not well understood. In a previous study, we used a perinatal bilateral enucleation mouse model to test some aspects of this interaction by reweighting sensory input to the developing cortex. Visual deprivation at birth resulted in a shift of intraneocortical connections (INCs) that aligned with ectopic ephrin A5 expression in the same location ten days later at postnatal day (P) 10. A prevailing question remained: Does visual deprivation first induce a change in gene expression, followed by a shift in INCs, or vice versa? In the present study, we address this question by investigating the neuroanatomy and patterns of gene expression in post-natal day (P) 1 and 4 mice following bilateral enucleation at birth. Our results demonstrate a rapid reduction in dorsal lateral geniculate nucleus (dLGN) size and ephrin A5 gene expression 24-hours post-enucleation, with more profound effects apparent at P4. The reduced nuclear size and diminished gene expression mirrors subtle changes in ephrin A5 expression evident in P1 and P4 enucleated neocortex, 11 and 8 days prior to natural eye opening, respectively. Somatosensory and visual INCs were indistinguishable between P1 and P4 mice bilaterally enucleated at birth, indicating that perinatal bilateral enucleation initiates a rapid change in gene expression (within one day) followed by an alteration of sensory INCs later on (second postnatal week). With these results, we gain a deeper understanding of how gene expression and

  10. Uveal Melanoma Recurrence After Fractionated Proton Beam Therapy: Comparison of Survival in Patients Treated With Reirradiation or With Enucleation

    SciTech Connect

    Marucci, Laura; Ancukiewicz, Marek; Lane, Anne Marie; Collier, John M.; Gragoudas, Evangelos S.; Munzenrider, John E.

    2011-03-01

    Purpose: To retrospectively compare survival in recurrent uveal melanoma, between patients treated by enucleation or by a second course of fractionated proton beam therapy (PBT). Methods and Materials: Tumor recurrence was documented in 73 patients treated with PBT for uveal melanoma. Of the patients, 31 received a second course of PBT and 42 underwent enucleation. The mean patient age was 56 and 61 years for those undergoing enucleation and those undergoing reirradiation, respectively. Both primary and recurrent tumors were larger in patients undergoing enucleation. Tumor location and the presence or absence of ciliary body involvement did not differ significantly between the groups. The median follow-up after enucleation and after re-treatment was 79 and 59 months, respectively. Cumulative rates of outcomes and differences in rates between the reirradiated and enucleation groups were calculated by the Cox proportional hazards model and the log-rank test, respectively. Results: The median survival duration in the enucleated and reirradiated groups was 42 and 90 months, respectively. The median time free of metastases was 38 months in enucleated patients and 97 months in reirradiated patients. At 5 years after enucleation and after reirradiation, the probability of overall survival was 36% and 63%, respectively (p = 0.040, log-rank test); the probability of freedom from metastases was 31% and 66%, respectively (p = 0.028, log-rank test). These differences persisted after adjustment for recurrent tumor largest diameter and volume at the time of reirradiation or enucleation. Conclusions: This retrospective analysis suggests that survival in reirradiated patients is not compromised by administration of a second course of PBT for recurrent uveal melanoma.

  11. Laser treatment of benign prostate enlargement--which laser for which prostate?

    PubMed

    Rieken, Malte; Bachmann, Alexander

    2014-03-01

    Laser-based prostatectomy for benign prostatic obstruction has emerged over the past decade as a treatment alternative to transurethral resection of the prostate (TURP) and open prostatectomy. These techniques set new standards in minimally invasive surgery and aim to obviate the complications of open surgery while ensuring durability of outcomes. Enucleation, which mimics open prostatectomy in that the whole prostate adenoma is removed, and vaporization, which involves ultra-rapid heating of superficial tissue layers and subsequent ablation, are the most often used surgical techniques in laser prostatectomy. The wavelength and the power output of the laser influence the tissue-laser interactions, which determine the physical properties and the safety profile of the technique. Holmium laser enucleation of the prostate (HoLEP) and GreenLight(™) laser vaporization of the prostate are the two reference techniques for laser prostatectomy, both of which have been shown to be as effective as TURP, while offering advantages in the safety profile in various randomized trials. Thulium laser enucleation of the prostate (ThuLEP) shares similarities with HoLEP and has shown encouraging results. However, more controlled trials with longer follow-up assessment are needed. Diode lasers come in various wavelengths and fibre designs and have been used for vaporization and enucleation, but require high-quality data to support their clinical use. PMID:24595121

  12. Use of demineralized bone as an osteoinductive orbital enucleation implant in the rabbit.

    PubMed

    Sires, B S; Geggel, H S; Heffernan, J T; Crane, R D; Holds, J B

    1993-06-01

    Implanted allogeneic demineralized bone particles (DBP) may be transformed into endochondral bone by inductive or conductive new bone formation. Using a rabbit model, enucleation or evisceration was performed, and DBP was implanted into the socket. Histology confirmed endochondral bone formation in both groups. A morphologic difference existed between enucleation and evisceration: compact bone was produced following evisceration, and cancellous bony spheres were formed following enucleation. Serial quantitative computed tomography (qCT) was performed to monitor mineral density and proved to be an ideal technique to monitor bone mineralization noninvasively in the postoperative orbit. Bone mineral density (BMD, mg/ml) increased approximately 300% in DBP implanted orbits when compared to controls at 6 weeks. The ideal mass/volume ratio of DBP to socket volume was 400 mg/ml. The rapidly formed bone is well vascularized and creates a stable integrated orbital implant, following enucleation and evisceration surgery. DBP implantation into the central orbit results in inductive bone formation with interesting potential in socket and orbit reconstruction. PMID:8323902

  13. Chromatin Condensation and Enucleation in Red Blood Cells: An Open Question.

    PubMed

    Baron, Margaret H; Barminko, Jeffrey

    2016-03-01

    Differentiating erythroid cells undergo dramatic changes in morphology, with reduction in cell size, chromatin and nuclear condensation, and enucleation. In this issue of Developmental Cell, Zhao et al. (2016) show that these events are associated with the formation of transient, recurring nuclear openings and selective histone release mediated by caspase-3. PMID:26954541

  14. Enucleation is Better for a Giant Hemangioma Proximal to the Hepatic Portal Vascular Structures.

    PubMed

    Wu, Chuan-Xing; Bao, Wan-Yuan; Zhu, Feng

    2016-08-01

    The aim of this study is to compare the effect of liver enucleation with resection of a giant hemangioma proximal to the hepatic portal vascular structures. From 2008 to 2014, 53 patients with giant hemangiomas proximal to the hepatic portal vascular structures underwent surgery in our hospital by the same surgical team. The indications for surgery included a tumor size greater than 8 cm, a middle size greater than 4 cm but with abdominal pain, a rapidly increased tumor size with uncertain malignancy, or tumor rupture. Thirty-two patients (60 %) had pain only, 15 (29 %) had pain with tumor growth, 5 patients (9 %) had an uncertain diagnosis, and 1 patient (2 %) had tumor rupture. Enucleation was performed in 31 patients and liver resection was performed in 22 patients. There were no significant differences in the size of the hemangioma (13.9 ± 3.1 vs 12.3 ± 5.5 cm; P > 0.05), preoperative liver function tests, hemoglobin levels, and platelet counts between the enucleation and resection groups. The mean intraoperative blood loss was significantly less in the enucleation group compared with the resection group (350.9 ± 89.8 vs 988 ± 91.7 mL; P < 0.01), and the enucleation group had a significantly shorter mean operative time (1.7 ± 0.4 vs 2.9 ± 0.9 h; P < 0.01) and significantly shorter duration of hospital stay (9.6 ± 4.2 vs 14.7 ± 3.7 days; P < 0.05). Five patients in the resection group and only 1 patient in the enucleation group had major postoperative complications. Compared to liver resection, enucleation is safer and faster for liver hemangiomas proximal to the hepatic portal vascular structures and is associated with fewer complications. PMID:27574349

  15. Identification of a Murine Erythroblast Subpopulation Enriched in Enucleating Events by Multi-spectral Imaging Flow Cytometry

    PubMed Central

    Konstantinidis, Diamantis G.; Pushkaran, Suvarnamala; Giger, Katie; Manganaris, Stefanos; Zheng, Yi; Kalfa, Theodosia A.

    2014-01-01

    Erythropoiesis in mammals concludes with the dramatic process of enucleation that results in reticulocyte formation. The mechanism of enucleation has not yet been fully elucidated. A common problem encountered when studying the localization of key proteins and structures within enucleating erythroblasts by microscopy is the difficulty to observe a sufficient number of cells undergoing enucleation. We have developed a novel analysis protocol using multiparameter high-speed cell imaging in flow (Multi-Spectral Imaging Flow Cytometry), a method that combines immunofluorescent microscopy with flow cytometry, in order to identify efficiently a significant number of enucleating events, that allows to obtain measurements and perform statistical analysis. We first describe here two in vitro erythropoiesis culture methods used in order to synchronize murine erythroblasts and increase the probability of capturing enucleation at the time of evaluation. Then, we describe in detail the staining of erythroblasts after fixation and permeabilization in order to study the localization of intracellular proteins or lipid rafts during enucleation by multi-spectral imaging flow cytometry. Along with size and DNA/Ter119 staining which are used to identify the orthochromatic erythroblasts, we utilize the parameters “aspect ratio” of a cell in the bright-field channel that aids in the recognition of elongated cells and “delta centroid XY Ter119/Draq5” that allows the identification of cellular events in which the center of Ter119 staining (nascent reticulocyte) is far apart from the center of Draq5 staining (nucleus undergoing extrusion), thus indicating a cell about to enucleate. The subset of the orthochromatic erythroblast population with high delta centroid and low aspect ratio is highly enriched in enucleating cells. PMID:24962543

  16. Ki-67 immunostaining in uveal melanoma. The effect of pre-enucleation radiotherapy

    SciTech Connect

    Mooy, C.M.; de Jong, P.T.; Van der Kwast, T.H.; Mulder, P.G.; Jager, M.J.; Ruiter, D.J. )

    1990-10-01

    The reactivity of 33 choroidal and ciliary body melanomas with monoclonal antibody Ki-67, which recognizes a proliferation associated nuclear antigen, has been assessed and compared with clinicopathologic parameters. In 23 cases, 8 Gy irradiation was given 2 days before enucleation. Nonirradiated melanomas had a significantly higher proliferation rate as defined by staining with monoclonal antibody Ki-67 as compared with irradiated tumors (P = 0.007). Similarly, a strong relationship was found between pre-enucleation irradiation and low mitotic activity (P = 0.001). There was no significant correlation between the presence of Ki-67-positive nuclei and histologic classification, largest tumor diameter, localization of the tumor, age, sex, scleral invasion, pigmentation, and lymphocytic infiltration. The relevance of Ki-67 immunohistochemistry for the assessment of the life prognosis of patients with uveal melanoma has to be studied prospectively.

  17. Bilateral self-enucleation in acute transient psychotic disorder: the influence of sociocultural factors on psychopathology.

    PubMed

    Harish, Thippeswamy; Chawan, Namdev; Rajkumar, Ravi Philip; Chaturvedi, Santosh Kumar

    2012-07-01

    Self-inflicted eye injuries are rare but a devastating consequence of a serious mental disorder. Bilateral self-enucleation also known as oedipism has been documented in ancient texts and myths. Various biologic, psychologic, and social theories have been put forward to explain this rare phenomenon. In this report, we describe a case of oedipism, which highlights the influence of sociocultural factors on the psychopathology in acute transient psychotic disorder. PMID:21864835

  18. Periumbilical fat auto-graft associated to a porous orbital implant for socket reconstruction after enucleation.

    PubMed

    Medel, Ramon; Alonso, Tirso; Pelaez, Francisco; Vasquez, LuzMaria

    2016-08-01

    Having to remove the sclera, fat and the optic nerve in patients undergoing an enucleation, translates in a larger volume that needs to be replaced to achieve good motility and aesthetic results. Using a 20 or 22 mm implant can only partially replace the removed volume. We report the results of our enucleation technique, which includes the use of a porous orbital implant combined with a primary fat graft to replace a higher percentage of the removed volume to achieve a better cosmetic outcome and to avoid implant related complications in high risk patients. Prospective, non-randomized study of enucleated patients for whom porous orbital implantation was performed with anterior placement of a fat auto-graft. The development of implant extrusion or exposure was recorded as well as the presence of conjunctival wound dehiscence and infection. Orbital volume was clinically and radiologically evaluated as well. Twenty-eight patients were included, with a postop follow-up of at least 6 months (6-79 months). No cases of migration or extrusion were found. One case of a large exposure resolved completely. All MRI demonstrated proper implant-graft integration and vascularisation. The aesthetic result and the symmetry were very adequate, with Hertel differences of less than 2 mm in all cases and good motility range. The fat graft is well tolerated, showing low incidence of implant-related complications whilst maintaining good volume and motility. PMID:27322024

  19. Impediments to eye transplantation: ocular viability following optic-nerve transection or enucleation

    PubMed Central

    Ellenberg, D; Shi, J; Jain, S; Chang, J-H; Ripps, H; Brady, S; Melhem, E R; Lakkis, F; Adamis, A; Chen, D-F; Ellis-Behnke, R; Langer, R S; Strittmatter, S M; Azar, D T

    2010-01-01

    Maintenance of ocular viability is one of the major impediments to successful whole-eye transplantation. This review provides a comprehensive understanding of the current literature to help guide future studies in order to overcome this hurdle. A systematic multistage review of published literature was performed. Three specific questions were addressed: (1) Is recovery of visual function following eye transplantation greater in cold-blooded vertebrates when compared with mammals? (2) Is outer retina function following enucleation and reperfusion improved compared with enucleation alone? (3) Following optic-nerve transection, is there a correlation between retinal ganglion cell (RGC) survival and either time after transection or proximity of the transection to the globe? In a majority of the studies performed in the literature, recovery of visual function can occur after whole-eye transplantation in cold-blooded vertebrates. Following enucleation (and reperfusion), outer retinal function is maintained from 4 to 9 h. RGC survival following optic-nerve transection is inversely related to both the time since transection and the proximity of transection to the globe. Lastly, neurotrophins can increase RGC survival following optic-nerve transection. This review of the literature suggests that the use of a donor eye is feasible for whole-eye transplantation. PMID:19286686

  20. Three histopathological types of retinoblastoma and their relation to heredity and age of enucleation.

    PubMed Central

    Moll, A C; Koten, J W; Lindenmayer, D A; Everse, L A; Tan, K E; Hamburg, A; Faber, J A; Den Otter, W

    1996-01-01

    The histopathology of 61 eyes was studied with special attention to the morphology of the retina adjacent to the main tumour. Three retinal types were distinguished. Retina type 1 (RT-1, 28 specimens) contained a single tumour that was sharply demarcated from surrounding normal retina. In retina type 2 (RT-2, 29 specimens) large parts of the retina were affected and the main tumour mass gradually blended with the adjacent pathological retina. Retina type 3 (RT-3, four specimens) was characterised by a retina almost entirely affected by diffuse tumour growth. RT-1 correlated significantly with early enucleation (0-3 years) both in hereditary and non-hereditary cases. RT-2 was seen in eyes enucleated later (2-5 years). The progressing tumour may release growth factors in the intraocular space that stimulate the cells of the adjacent retina and lead to multiple new primary tumours in the adjacent retinal area. RT-3 was only present in non-hereditary cases with late enucleation (at 2-5 years). Hereditary retinoblastoma cases are usually detected early. Therefore in hereditary cases RT-1 is significantly more common than RT-2. In 25 eyes of the 44 patients with unilateral sporadic retinoblastoma, multifocal tumours of the retina were observed. Such cases should not mistakenly be classified as hereditary cases on the basis of the histological pattern of multifocality of the tumour process. Images PMID:8950672

  1. Iron dose-dependent differentiation and enucleation of human erythroblasts in serum-free medium.

    PubMed

    Byrnes, Colleen; Lee, Y Terry; Meier, Emily R; Rabel, Antoinette; Sacks, David B; Miller, Jeffery L

    2016-02-01

    Improvements in ex vivo generation of enucleated red blood cells are being sought for erythroid biology research, toward the ultimate goal of erythrocyte engineering for clinical use. Based upon the high levels of iron-saturated transferrin in plasma serum, it was hypothesized that terminal differentiation in serum-free media may be highly dependent on the concentration of iron. Here adult human CD34(+) cells were cultured in a serum-free medium containing dosed levels of iron-saturated transferrin (holo-Tf, 0.1-1.0 mg/ml). Iron in the culture medium was reduced, but not depleted, with erythroblast differentiation into haemoglobinized cells. At the lowest holo-Tf dose (0.1 mg/ml), terminal differentiation was significantly reduced and the majority of the cells underwent apoptotic death. Cell survival, differentiation and enucleation were enhanced as the holo-Tf dose increased. These data suggest that adequate holo-Tf dosing is critical for terminal differentiation and enucleation of human erythroblasts generated ex vivo in serum-free culture conditions. Published 2013. This article is a US Government work and is in the public domain in the USA. PMID:23606586

  2. Lasers.

    ERIC Educational Resources Information Center

    Schewe, Phillip F.

    1981-01-01

    Examines the nature of laser light. Topics include: (1) production and characteristics of laser light; (2) nine types of lasers; (3) five laser techniques including holography; (4) laser spectroscopy; and (5) laser fusion and other applications. (SK)

  3. Effects of neonatal enucleation on the functional organization of the superior colliculus in the golden hamster.

    PubMed Central

    Rhoades, R W

    1980-01-01

    1. The responses of visual, auditory and somatosensory superior collicular neurones were investigated using extracellular single unit recording techniques in hamsters which were subjected to the removal of one eye on the day of birth. 2. Neonatal enucleation resulted in a marked increase in the region of the colliculus from which visual neurones activated by stimulation of the ipsilateral eye could be recorded. In most cases the visuotopic representation in the colliculus ipsilateral to the remaining eye mirrored that observed in the contralateral tectum along both the rostrocaudal and mediolateral axes: in both colliculi temporal retina projected rostrally and inferior retina medially. In some animals, however, there appeared to be a dual mapping of the remaining eye onto the ipsilateral tectum. In these hamsters the central portion of the visual field was represented twice along the rostrocaudal axis of colliculus. 3. No changes in the topography of the somatosensory and auditory representations in the tectum were observed following neonatal enucleation. 4. The laminar distribution of visual neurones in the ipsilateral colliculus was markedly altered in the neonatally enucleated hamsters. Very few exclusively visual units were encountered in the layers ventral to the stratum opticum and almost all of the visual cells recorded in the ipsilateral colliculus were isolated within 150 microM of the tectal surface. 5. In the posterior half of the ipsilateral tectum a large number of extravisually responsive cells were encountered in the stratum griseum superficiale and stratum opticum. This was not the case in the colliculus contralateral to the remaining eye, nor has it ever been observed in normal hamsters. 6. Recordings from animals subjected to both neonatal enucleation and acute bilateral removal of somatosensory and auditory cortex indicated that the projections from these areas to the colliculus were not essential to the observed changes in laminar organization

  4. Wilbrand's knee of the primate optic chiasm is an artefact of monocular enucleation.

    PubMed Central

    Horton, J C

    1997-01-01

    PURPOSE: The anterior chiasmal syndrome consists of a temporal hemianopia or complete visual field loss in one eye, plus a superior temporal hemianopia in the other eye. The superior temporal hemianopia in the other eye is thought to result from injury to Wilbrand's Knee of the optic chiasm. Wilbrand's Knee is a loop of decussating fibers which detours into the contralateral optic nerve before entering the optic tract. I studied the organization of fibers in the optic chiasm of monkeys and humans to verify the existence of Wilbrand's Knee and to elucidate further the pattern of visual field loss seen from lesions of the sellar region. METHODS: The primary optic pathway was labelled in monkeys by injection of [3H] proline into one eye, followed by autoradiography. There were 8 intact Rhesus monkeys and 3 intact squirrel monkeys. In addition, the optic pathway was studied in the Rhesus monkey 6 months and 4 years after monocular enucleation. The optic chiasm was also examined using myelin stains in specimens obtained post-mortem from 3 patients. The patients had lost 1 eye 5 months, 2 years, and 28 years prior to their deaths. Finally, clinical observations were recorded in 3 patients with the anterior chiasmal syndrome. RESULTS: In normal Rhesus and squirrel monkeys, optic nerve fibers crossed the optic chiasm without entering the contralateral optic nerve. After short-term monocular enucleation, fibers from the normal optic nerve were drawn closer to the entry zone of the degenerating optic nerve, but Wilbrand's Knee was still absent. After long-term enucleation, a typical Wilbrand's Knee was induced to form. In the human, Wilbrand's Knee was absent 5 months after monocular enucleation, but emerged in the two cases involving long-term enucleation, in a fashion analogous to the monkey. The case reports describe 3 patients with variants of the anterior chiasmal syndrome from parasellar tumors. CONCLUSIONS: Wilbrand's Knee does not exist in the normal primate optic

  5. The combined effects of unilateral enucleation and rearing in a 'dim' red light on synapse-to-neuron ratios in the rat visual cortex.

    PubMed Central

    Bedi, K S

    1989-01-01

    One day old rats had their right eyes removed and together with non-enucleated controls were raised in either 'light' or 'dark' (red light) conditions from birth until 39 days of age. This resulted in four groups of animals: light-reared enucleated, light-reared non-enucleated, dark-reared enucleated and dark-reared non-enucleated. All animals were killed by intracardiac perfusion with 2.5% sodium cacodylate-buffered glutaraldehyde at 39 days of age. Pieces of visual cortex (Area 17) from both right and left cerebral hemispheres of each animal were dissected out and processed for electron microscopy. Stereological procedures were used to estimate the synapse-to-neuron ratios in Layers II-III of these cortices. Light-reared non-enucleated rats had about 16,000 synapses per neuron in both right and left visual cortices. Rearing non-enucleated rats in the dark reduced this value to about 11,500. The synapse-to-neuron ratio of unilaterally enucleated rats raised in the light was not significantly different from that observed in light-reared non-enucleated rats. Combined dark-rearing and unilateral enucleation did reduce the synapse-to-neuron ratio but not to any greater extent than did dark-rearing alone. However, there was a suggestion of a differential effect between the right and left cortices in these enucleated, dark-reared animals. These results demonstrate the importance of light stimulation for the normal development of interneuronal connectivity of the visual cortex. They also show that the effects of unilateral enucleation for the visual cortex are not as great as those previously observed for the superior colliculi in the same animals, at least as far as synapse-to-neuron ratios are concerned. Images Fig. 1 Fig. 2 PMID:2630542

  6. Advanced Unilateral Retinoblastoma: The Impact of Ophthalmic Artery Chemosurgery on Enucleation Rate and Patient Survival at MSKCC

    PubMed Central

    Abramson, David H.; Fabius, Armida W. M.; Issa, Reda; Francis, Jasmine H.; Marr, Brian P.; Dunkel, Ira J.; Gobin, Y. Pierre

    2015-01-01

    Purpose To report on the influence of ophthalmic artery chemosurgery (OAC) on enucleation rates, ocular and patient survival from metastasis and impact on practice patterns at Memorial Sloan Kettering for children with advanced intraocular unilateral retinoblastoma. Patients and Methods Single-center retrospective review of all unilateral retinoblastoma patients with advanced intraocular retinoblastoma treated at MSKCC between our introduction of OAC (May 2006) and December 2014. End points were ocular survival, patient survival from metastases and enucleation rates. Results 156 eyes of 156 retinoblastoma patients were included. Primary enucleation rates have progressively decreased from a rate of >95% before OAC to 66.7% in the first year of OAC use to the present rate of 7.4%. The percent of patients receiving OAC has progressively increased from 33.3% in 2006 to 92.6% in 2014. Overall, ocular survival was significantly better in eyes treated with OAC in the years 2010–2014 compared to 2006–2009 (p = 0.023, 92.7% vs 68.0% ocular survival at 48 months). There have been no metastatic deaths in the OAC group but two patients treated with primary enucleation have died of metastatic disease. Conclusion OAC was introduced in 2006 and its impact on patient management is profound. Enucleation rates have decreased from over 95% to less than 10%. Our ocular survival rate has also significantly and progressively improved since May 2006. Despite treating more advanced eyes rather then enucleating them patient survival has not been compromised (there have been no metastatic deaths in the OAC group). In our institution, enucleation is no longer the most common treatment for advanced unilateral retinoblastoma. PMID:26709699

  7. Strain differences of the effect of enucleation and anophthalmia on the size and growth of sensory cortices in mice.

    PubMed

    Massé, Ian O; Guillemette, Sonia; Laramée, Marie-Eve; Bronchti, Gilles; Boire, Denis

    2014-11-01

    Anophthalmia is a condition in which the eye does not develop from the early embryonic period. Early blindness induces cross-modal plastic modifications in the brain such as auditory and haptic activations of the visual cortex and also leads to a greater solicitation of the somatosensory and auditory cortices. The visual cortex is activated by auditory stimuli in anophthalmic mice and activity is known to alter the growth pattern of the cerebral cortex. The size of the primary visual, auditory and somatosensory cortices and of the corresponding specific sensory thalamic nuclei were measured in intact and enucleated C57Bl/6J mice and in ZRDCT anophthalmic mice (ZRDCT/An) to evaluate the contribution of cross-modal activity on the growth of the cerebral cortex. In addition, the size of these structures were compared in intact, enucleated and anophthalmic fourth generation backcrossed hybrid C57Bl/6J×ZRDCT/An mice to parse out the effects of mouse strains and of the different visual deprivations. The visual cortex was smaller in the anophthalmic ZRDCT/An than in the intact and enucleated C57Bl/6J mice. Also the auditory cortex was larger and the somatosensory cortex smaller in the ZRDCT/An than in the intact and enucleated C57Bl/6J mice. The size differences of sensory cortices between the enucleated and anophthalmic mice were no longer present in the hybrid mice, showing specific genetic differences between C57Bl/6J and ZRDCT mice. The post natal size increase of the visual cortex was less in the enucleated than in the anophthalmic and intact hybrid mice. This suggests differences in the activity of the visual cortex between enucleated and anophthalmic mice and that early in-utero spontaneous neural activity in the visual system contributes to the shaping of functional properties of cortical networks. PMID:25242615

  8. Chemically induced enucleation of activated bovine oocytes: chromatin and microtubule organization and production of viable cytoplasts.

    PubMed

    Saraiva, Naiara Zoccal; Oliveira, Clara Slade; Leal, Cláudia Lima Verde; de Lima, Marina Ragagnin; Del Collado, Maite; Vantini, Roberta; Monteiro, Fabio Morato; Niciura, Simone Cristina Méo; Garcia, Joaquim Mansano

    2015-12-01

    As the standard enucleation method in mammalian nuclear transfer is invasive and damaging to cytoplast spatial organization, alternative procedures have been developed over recent years. Among these techniques, chemically induced enucleation (IE) is especially interesting because it does not employ ultraviolet light and reduces the amount of cytoplasm eliminated during the procedure. The objective of this study was to optimize the culture conditions with demecolcine of pre-activated bovine oocytes for chemically IE, and to evaluate nuclear and microtubule organization in cytoplasts obtained by this technique and their viability. In the first experiment, a negative effect on oocyte activation was verified when demecolcine was added at the beginning of the process, reducing activation rates by approximately 30%. This effect was not observed when demecolcine was added to the medium after 1.5 h of activation. In the second experiment, although a reduction in the number of microtubules was observed in most oocytes, these structures did not disappear completely during assessment. Approximately 50% of treated oocytes presented microtubule reduction at the end of the evaluation period, while 23% of oocytes were observed to exhibit the complete disappearance of these structures and 28% exhibited visible microtubules. These findings indicated the lack of immediate microtubule repolymerization after culture in demecolcine-free medium, a fact that may negatively influence embryonic development. However, cleavage rates of 63.6-70.0% and blastocyst yield of 15.5-24.2% were obtained in the final experiment, without significant differences between techniques, indicating that chemically induced enucleation produces normal embryos. PMID:25318529

  9. Effects of dexmedetomidine for retrobulbar anesthesia in orbital ball implants after enucleation surgery

    PubMed Central

    Ye, Weidi; Hu, Zhiyong; Jin, Xiuming; Wang, Pei

    2015-01-01

    Background: Dexmedetomidine (DEX) can prolong the duration of local anesthetics, but the use of retrobulbar DEX has not been fully elucidated. This study was designed to determine the effects of adding DEX to lidocaine-bupivacaine for retrobulbar block in orbital ball implants after enucleation surgery. Materials and Methods: A total of 200 patients of both sexes aged 30–60 years of American Society of Anesthesiologists I and II, scheduled for orbital ball implants after enucleation surgery, were enrolled for the study. Patients were randomly assigned into one of the two groups: Control (n = 100) received lidocaine-bupivacaine retrobulbar block, DEX (n = 100) received lidocaine-bupivacaine plus 1 ug/kg DEX retrobulbar block. Hemodynamic data, duration of motor and sensory blocks, pain by visual analog scale, bispectral index (BIS), side effects, consumption of dezocine as a rescue analgesic, patient and surgeon satisfaction were recorded. Results: Duration of analgesia was prolonged in the DEX, compared with the control group ([258.35 ± 66.82 min] as [130.75 ± 29.52 min], [P < 0.05]). The median number of postoperative analgesic requests per patient during the first 24 h was decreased in the DEX group (P < 0.05). In the first 24 postoperative hours, DEX group consumed significantly less dezocine (P < 0.05). BIS values and mean arterial pressure remained lower in the DEX group, but within the safe range (P < 0.05). The side effect profile was similar between the two groups. Patients and surgeon satisfaction were higher in the DEX group (P < 0.05). Demographic characteristics were comparable in both groups (P > 0.05). Conclusion: Retrobulbar DEX reduces consumption of rescue analgesic, prolonged the duration of retrobulbar block, improved postoperative pain, provided better sedation effects, and increased patient and surgeon satisfaction after orbital ball implants after enucleation surgery. PMID:26632125

  10. Worldwide Enucleation Techniques and Materials for Treatment of Retinoblastoma: An International Survey

    PubMed Central

    Mourits, Daphne L.; Hartong, Dyonne T.; Bosscha, Machteld I.; Kloos, Roel J. H. M.; Moll, Annette C.

    2015-01-01

    Purpose To investigate the current practice of enucleation with or without orbital implant for retinoblastoma in countries across the world. Methods A digital survey identifying operation techniques and material used for orbital implants after enucleation in patients with retinoblastoma. Results We received a response of 58 surgeons in 32 different countries. A primary artificial implant is routinely inserted by 42 (72.4%) surgeons. Ten (17.2%) surgeons leave the socket empty, three (5.2%) decide per case. Other surgeons insert a dermis fat graft as a standard primary implant (n=1), or fill the socket in a standard secondary procedure (n=2; one uses dermis fat grafts and one artificial implants). The choice for porous implants was more frequent than for non-porous implants: 27 (58.7%) and 15 (32.6%), respectively. Both porous and non-porous implant types are used by 4 (8.7%) surgeons. Twenty-five surgeons (54.3%) insert bare implants, 11 (23.9%) use separate wrappings, eight (17.4%) use implants with prefab wrapping and two insert implants with and without wrapping depending on type of implant. Attachment of the muscles to the wrapping or implant (at various locations) is done by 31 (53.4%) surgeons. Eleven (19.0%) use a myoconjunctival technique, nine (15.5%) suture the muscles to each other and seven (12.1%) do not reattach the muscles. Measures to improve volume are implant exchange at an older age (n=4), the use of Restylane SQ (n=1) and osmotic expanders (n=1). Pegging is done by two surgeons. Conclusion No (worldwide) consensus exists about the use of material and techniques for enucleation for the treatment of retinoblastoma. Considerations for the use of different techniques are discussed. PMID:25767872

  11. [Enzyme histochemical examinations of the visual system of the adult rat following unilateral enucleation].

    PubMed

    Leibnitz, L; Bär, B

    1979-01-01

    12 adult white lab-rats were enucleated and after a survival period of 1, 3, 7 and 30 days the activities of GABA-T, GDH, LDH, SDH and GPDH were demonstrated histochemically in the Tractus opticus (To), Corpus geniculatum laterale, pars dorsalis (CGLd) et ventralis (CGLv), Colliculus superior (Cs) and Nucleus olivaris praetectalis (Nop). Since the ipsi- and contralateral grisea are always in the same tissue section the enzyme activities can be quantitatively compared by visual impression without a greater mistake. In To enucleation caused a hypertrophy of astrocytes together with an increase of the activities of GABA-T, GDH, LDH, and GPDH in these cells. The reactions indicate a more intensive metabolism in connection with the myelin degradation. In CGLd, CGLv, Cs and Nop following enucleation there appeared contralaterally a graded loss in the activities of GDH, LDH, GPDH, and GABA-T; only SDH scarely changed its activity. The fastest and strongest reaction was found in Cs and Nop, while CGLd and CGLv reacted later and to a less degree. In CGLv the enzyme reaction was limited to the lateral part of the nucleus. As diminution of activity is caused by degeneration of the retinal terminals the effected enzymes must be localised in cytoplasma and mitochondria of these terminals. Taking into account findings from literature the following is concluded from the time patterns, the degree of diminution of the enzyme activities and the relation of retinal to extraretinal terminals in the individual nuclei: GABA probably acts as a transmitter in interneurons of CGLd, Cs, and Nop. Glutamate is a transmitter in Cs and Nop. PMID:121134

  12. A simple technique for hemostasis control after enucleation of deep located liver tumors or after liver trauma.

    PubMed

    Machado, Marcel A; Surjan, Rodrigo C; Basseres, Tiago; Makdissi, Fábio F

    2016-01-01

    Modern liver techniques allowed the development of segment-based anatomical liver resections. Nevertheless, there is still a place for nonanatomical liver resections. However, in some cases, there is a need for enucleation of deep located liver tumors. The main problem with enucleation of a liver tumor deeply located in the middle of the liver is the control of bleeding resulting from the rupture of small or medium vessels. The authors describe a simple way to control the bleeding without the use of any special instrument or material. This technique can also be used to control bleeding from penetrating liver injury. PMID:26846270

  13. Telelap Alf-X-Assisted Laparoscopy for Ovarian Cyst Enucleation: Report of the First 10 Cases.

    PubMed

    Gueli Alletti, Salvatore; Rossitto, Cristiano; Fanfani, Francesco; Fagotti, Anna; Costantini, Barbara; Gidaro, Stefano; Monterossi, Giorgia; Selvaggi, Luigi; Scambia, Giovanni

    2015-01-01

    This prospective single-institutional clinical trial sought to assess the safety and feasibility of laparoscopic benign ovarian cyst enucleation with a novel robotic-assisted laparoscopic system. Here we report a series of 10 patients treated using the Telelap ALF-X system in the first clinical application on patients at the Division of Gynecologic Oncology, Catholic University of the Sacred Heart of Rome. The primary inclusion criterion was the presence of monolateral ovarian cyst without a preoperative assessment suspicious for malignancy. Intraoperative data, including docking time, operative time, estimated blood loss, intraoperative and perioperative complications, and conversion to either standard laparoscopy or laparotomy, were collected. The cysts were removed with an ovary-sparing technique with respect to conservative surgical principles. The median operative time was 46.3 minutes, and patients without postoperative complications were discharged at 1 or 2 days after the procedure. Telelap ALF-X laparoscopic enucleation of benign ovarian cysts with an ovary-sparing technique is feasible, safe, and effective; however, more clinical data are needed to determine whether this approach can offer any other benefits over other minimally invasive surgical techniques. PMID:25987523

  14. A technique for evisceration as an alternative to enucleation in birds of prey: 19 cases.

    PubMed

    Murray, Maureen; Pizzirani, Stefano; Tseng, Florina

    2013-06-01

    Ocular trauma is common in birds of prey presented to wildlife clinics and rehabilitation centers. Enucleation is the procedure most commonly described for treatment of end-stage ocular disease or chronically painful eyes in birds; however, there are several disadvantages and risks to this procedure. While evisceration has been suggested as an alternative, it has not been described for multiple cases or with long-term follow-up data in birds of prey. This report details an evisceration technique performed in 5 captive birds of prey of 4 different species (1 eastern screech owl [Megascops asio], 1 great horned owl [Bubo virginianus], 2 red-tailed hawks [Buteo jamaicensis], and 1 bald eagle [Haliaeetus leucocephalus]) with long-term follow-up information. In addition, this report describes 14 cases of free-living owls of 3 different species (1 great horned owl, 4 barred owls [Strix varia], and 9 eastern screech owls) on which this technique was performed from 2004 to 2011 and which were subsequently released to the wild. Because of the limited risk of complications and the less-severe disruption of facial symmetry, which may be particularly important in owls that are candidates for release to the wild, evisceration should be considered over enucleation in birds of prey that require surgical intervention for the management of severe sequelae to ocular trauma. PMID:23971220

  15. In situ non-ischemic enucleation of multilocular cystic renal cell carcinoma using a microwave coagulator.

    PubMed

    Kagebayashi, Y; Hirao, Y; Samma, S; Fukui, Y; Hirohashi, R

    1995-11-01

    A case of multilocular cystic renal cell carcinoma is reported, in which nephron-sparing surgery was done using microwave tissue coagulation. A 37-year-old man was referred to our outpatient clinic for a multilocular cystic tumor, 4.5 cm in diameter, in the middle-lower portion of the right kidney, which was detected by ultrasound during a health checkup. The patient had been found to have the same cystic mass on a CT done during another health checkup 1.5 years before. The tumor showed no growth during the 1.5-year period. With a diagnosis of multilocular cystic renal cell carcinoma, T2N0M0, in situ non-ischemic tumor enucleation was done using a microwave tissue coagulator (Microtaze, Heiwa Electronics Industry Inc., Tokyo). Operation time was 150 minutes and blood loss was 135 cc. The histological diagnosis was renal cell carcinoma, T2N0M0V0, cystic type, clear cell subtype, grade 1. Diagnostic imaging done postoperatively showed no sign of damage to renal function. In this report, the characteristics of multilocular cystic renal carcinoma are reviewed from the literature, and the advantages of nephron-sparing surgery for this type of renal tumor are discussed. In addition, an operative technique of tumor enucleation used in this case and the characteristics of Microtaze are introduced. PMID:8749956

  16. Hereditary Spherocytosis and Hereditary Elliptocytosis: Aberrant Protein Sorting during Erythroblast Enucleation

    SciTech Connect

    Salomao, Marcela; Chen, Ke; Villalobos, Jonathan; Mohandas, Narla; An, Xiuli; Chasis, Joel Anne

    2010-02-08

    During erythroblast enucleation, membrane proteins distribute between extruded nuclei and reticulocytes. In hereditary spherocytosis (HS) and hereditary elliptocytosis (HE), deficiencies of membrane proteins, in addition to those encoded by the mutant gene, occur. Elliptocytes, resulting from protein 4.1R gene mutations, lack not only 4.1R but also glycophorin C, which links the cytoskeleton and bilayer. In HS resulting from ankyrin-1 mutations, band 3, Rh-associated antigen, and glycophorin A are deficient. The current study was undertaken to explore whether aberrant protein sorting, during enucleation, creates these membrane-spanning protein deficiencies. We found that although glycophorin C sorts to reticulocytes normally, it distributes to nuclei in 4.1R-deficient HE cells. Further, glycophorin A and Rh-associated antigen, which normally partition predominantly to reticulocytes, distribute to both nuclei and reticulocytes in an ankyrin-1-deficient murine model of HS. We conclude that aberrant protein sorting is one mechanistic basis for protein deficiencies in HE and HS.

  17. Critical review of lasers in benign prostatic hyperplasia (BPH).

    PubMed

    Gravas, Stavros; Bachmann, Alexander; Reich, Oliver; Roehrborn, Claus G; Gilling, Peter J; De La Rosette, Jean

    2011-04-01

    Laser treatment of benign prostatic hyperplasia has challenged transurethral resection of the prostate (TURP) due to advances in laser technology, better understanding of tissue-laser interactions and growing clinical experience. • Various lasers have been introduced including neodymium: yttrium aluminium garnet (YAG), holmium (Ho):YAG, potassium titanyl phosphate:YAG, thulium(Tm) and diode laser. Based on the different wave-length dependent laser-prostatic tissue interactions, the main techniques are coagulation, vaporization, resection and enucleation. • The present review aims to help urologists to distinguish and to critically evaluate the role of different laser methods in the treatment by using an evidence-based approach. It also details further evidence for use in specific patient groups (in retention, on anticoagulation) and addresses the issues of cost and learning curve. • Coagulation-based techniques have been abandoned; holmium ablation/resection of the prostate has been superseded by the enucleation technique Ho-laser enucleation of the prostate (HoLEP). The short-term efficacy of the emerging laser treatments such as diode and Tm prostatectomy has been suggested by low quality studies. HoLEP and photoselective vaporization of the prostate (PVP) represent valid clinical alternatives to TURP. HoLEP is the most rigorously analysed laser technique with durable efficacy for any prostate size and low early and late morbidity. PVP has grown in acceptance and popularity but long-term results from high quality studies are pending. PMID:21438974

  18. Concomitant Laparoendoscopic Single-Site Surgery for Vesicolithotomy and Finger-Assisted Single-Port Transvesical Enucleation of the Prostate

    PubMed Central

    Lee, Joo Yong; Kang, Dong Hyuk; Chung, Jae Hoon; Jo, Jung Ki

    2011-01-01

    Transurethral resection of the prostate is the most common surgery for benign prostatic hyperplasia. However, it doesn't work best for men with very large prostate and bladder stones. Herein we report our initial experience with concomitant laparoendoscopic single-site surgery and finger-assisted single-port transvesical enucleation of the prostate for the treatment of the condition. PMID:22259738

  19. Early Development of Cloned Bovine Embryos Produced from Oocytes Enucleated by Fluorescence Metaphase II Imaging Using a Conventional Halogen-Lamp Microscope

    PubMed Central

    Iwamoto, Daisaku; Yamagata, Kazuo; Kishi, Masao; Hayashi-Takanaka, Yoko; Kimura, Hiroshi; Wakayama, Teruhiko

    2015-01-01

    Abstract Enucleation of a recipient oocyte is one of the key processes in the procedure of somatic cell nuclear transfer (SCNT). However, especially in bovine species, lipid droplets spreading in the ooplasm hamper identification and enucleation of metaphase II (MII) chromosomes, and thereby the success rate of the cloning remains low. In this study we used a new experimental system that enables fluorescent observation of chromosomes in living oocytes without any damage. We succeeded in visualizing and removing the MII chromosome in matured bovine oocytes. This experimental system consists of injecting fluorescence-labeled antibody conjugates that bind to chromosomes and fluorescent observation using a conventional halogen-lamp microscope. The cleavage rates and blastocyst rates of bovine embryos following in vitro fertilization (IVF) decreased as the concentration of the antibody increased (p<0.05). The enucleation rate of the conventional method (blind enucleation) was 86%, whereas all oocytes injected with the antibody conjugates were enucleated successfully. Fusion rates and developmental rates of SCNT embryos produced with the enucleated oocytes were the same as those of the blind enucleation group (p>0.05). For the production of SCNT embryos, the new system can be used as a reliable predictor of the location of metaphase plates in opaque oocytes, such as those in ruminant animals. PMID:25826723

  20. Early development of cloned bovine embryos produced from oocytes enucleated by fluorescence metaphase II imaging using a conventional halogen-lamp microscope.

    PubMed

    Iwamoto, Daisaku; Yamagata, Kazuo; Kishi, Masao; Hayashi-Takanaka, Yoko; Kimura, Hiroshi; Wakayama, Teruhiko; Saeki, Kazuhiro

    2015-04-01

    Enucleation of a recipient oocyte is one of the key processes in the procedure of somatic cell nuclear transfer (SCNT). However, especially in bovine species, lipid droplets spreading in the ooplasm hamper identification and enucleation of metaphase II (MII) chromosomes, and thereby the success rate of the cloning remains low. In this study we used a new experimental system that enables fluorescent observation of chromosomes in living oocytes without any damage. We succeeded in visualizing and removing the MII chromosome in matured bovine oocytes. This experimental system consists of injecting fluorescence-labeled antibody conjugates that bind to chromosomes and fluorescent observation using a conventional halogen-lamp microscope. The cleavage rates and blastocyst rates of bovine embryos following in vitro fertilization (IVF) decreased as the concentration of the antibody increased (p<0.05). The enucleation rate of the conventional method (blind enucleation) was 86%, whereas all oocytes injected with the antibody conjugates were enucleated successfully. Fusion rates and developmental rates of SCNT embryos produced with the enucleated oocytes were the same as those of the blind enucleation group (p>0.05). For the production of SCNT embryos, the new system can be used as a reliable predictor of the location of metaphase plates in opaque oocytes, such as those in ruminant animals. PMID:25826723

  1. A case of a benign cementoblastoma treated by enucleation and apicoectomy.

    PubMed

    Gulses, Aydin; Bayar, Gurkan Rasit; Aydin, Cumhur; Sencimen, Metin

    2012-01-01

    Cementoblastoma is a rare, benign, odontogenic neoplasm of ectomesenchymal origin, representing less than 6% of all odontogenic tumors. Despite its well-known typical features, there are still controversies regarding the management of the condition. This article presents the case of a benign cementoblastoma in a 17-year-old girl. The lesion was typical and associated with the mandibular right first molar. Endodontic treatment of the involved tooth, enucleation of the cementoblastoma, and apicoectomy of the affected roots were performed. Removal of the tumor while preserving the associated tooth resulted in normal osseous healing and no evidence of recurrence after one year. Based on the findings of the current report, it can be suggested that, in properly selected cases, it is possible to remove cementoblastomas that affect molars without extracting the involved teeth. PMID:23220315

  2. Aqueous Angiography–Mediated Guidance of Trabecular Bypass Improves Angiographic Outflow in Human Enucleated Eyes

    PubMed Central

    Huang, Alex S.; Saraswathy, Sindhu; Dastiridou, Anna; Begian, Alan; Mohindroo, Chirayu; Tan, James C. H.; Francis, Brian A.; Hinton, David R.; Weinreb, Robert N.

    2016-01-01

    Purpose To assess the ability of trabecular micro-bypass stents to improve aqueous humor outflow (AHO) in regions initially devoid of AHO as assessed by aqueous angiography. Methods Enucleated human eyes (14 total from 7 males and 3 females [ages 52–84]) were obtained from an eye bank within 48 hours of death. Eyes were oriented by inferior oblique insertion, and aqueous angiography was performed with indocyanine green (ICG; 0.4%) or fluorescein (2.5%) at 10 mm Hg. With an angiographer, infrared and fluorescent images were acquired. Concurrent anterior segment optical coherence tomography (OCT) was performed, and fixable fluorescent dextrans were introduced into the eye for histologic analysis of angiographically positive and negative areas. Experimentally, some eyes (n = 11) first received ICG aqueous angiography to determine angiographic patterns. These eyes then underwent trabecular micro-bypass sham or stent placement in regions initially devoid of angiographic signal. This was followed by fluorescein aqueous angiography to query the effects. Results Aqueous angiography in human eyes yielded high-quality images with segmental patterns. Distally, angiographically positive but not negative areas demonstrated intrascleral lumens on OCT images. Aqueous angiography with fluorescent dextrans led to their trapping in AHO pathways. Trabecular bypass but not sham in regions initially devoid of ICG aqueous angiography led to increased aqueous angiography as assessed by fluorescein (P = 0.043). Conclusions Using sequential aqueous angiography in an enucleated human eye model system, regions initially without angiographic flow or signal could be recruited for AHO using a trabecular bypass stent. PMID:27588614

  3. Visual system plasticity in mammals: the story of monocular enucleation-induced vision loss

    PubMed Central

    Nys, Julie; Scheyltjens, Isabelle; Arckens, Lutgarde

    2015-01-01

    The groundbreaking work of Hubel and Wiesel in the 1960’s on ocular dominance plasticity instigated many studies of the visual system of mammals, enriching our understanding of how the development of its structure and function depends on high quality visual input through both eyes. These studies have mainly employed lid suturing, dark rearing and eye patching applied to different species to reduce or impair visual input, and have created extensive knowledge on binocular vision. However, not all aspects and types of plasticity in the visual cortex have been covered in full detail. In that regard, a more drastic deprivation method like enucleation, leading to complete vision loss appears useful as it has more widespread effects on the afferent visual pathway and even on non-visual brain regions. One-eyed vision due to monocular enucleation (ME) profoundly affects the contralateral retinorecipient subcortical and cortical structures thereby creating a powerful means to investigate cortical plasticity phenomena in which binocular competition has no vote.In this review, we will present current knowledge about the specific application of ME as an experimental tool to study visual and cross-modal brain plasticity and compare early postnatal stages up into adulthood. The structural and physiological consequences of this type of extensive sensory loss as documented and studied in several animal species and human patients will be discussed. We will summarize how ME studies have been instrumental to our current understanding of the differentiation of sensory systems and how the structure and function of cortical circuits in mammals are shaped in response to such an extensive alteration in experience. In conclusion, we will highlight future perspectives and the clinical relevance of adding ME to the list of more longstanding deprivation models in visual system research. PMID:25972788

  4. Shifts in Developmental Timing, and Not Increased Levels of Experience-Dependent Neuronal Activity, Promote Barrel Expansion in the Primary Somatosensory Cortex of Rats Enucleated at Birth

    PubMed Central

    Fetter-Pruneda, Ingrid; Ibarrarán-Viniegra, Ana Sofía; Martínez-Martínez, Eduardo; Sandoval-Velasco, Marcela; Uribe-Figueroa, Laura; Padilla-Cortés, Patricia; Mercado-Célis, Gabriela; Gutiérrez-Ospina, Gabriel

    2013-01-01

    Birth-enucleated rodents display enlarged representations of whiskers (i.e., barrels of the posteromedial subfield) in the primary somatosensory cortex. Although the historical view maintains that barrel expansion is due to incremental increases in neuronal activity along the trigeminal pathway during postnatal development, recent evidence obtained in experimental models of intramodal plasticity challenges this view. Here, we re-evaluate the role of experience-dependent neuronal activity on barrel expansion in birth-enucleated rats by combining various anatomical methods and sensory deprivation paradigms. We show that barrels in birth-enucleated rats were already enlarged by the end of the first week of life and had levels of metabolic activity comparable to those in control rats at different ages. Dewhiskering after the postnatal period of barrel formation did not prevent barrel expansion in adult, birth-enucleated rats. Further, dark rearing and enucleation after barrel formation did not lead to expanded barrels in adult brains. Because incremental increases of somatosensory experience did not promote barrel expansion in birth-enucleated rats, we explored whether shifts of the developmental timing could better explain barrel expansion during the first week of life. Accordingly, birth-enucleated rats show earlier formation of barrels, accelerated growth of somatosensory thalamocortical afferents, and an earlier H4 deacetylation. Interestingly, when H4 deacetylation was prevented with a histone deacetylases inhibitor (valproic acid), barrel specification timing returned to normal and barrel expansion did not occur. Thus, we provide evidence supporting that shifts in developmental timing modulated through epigenetic mechanisms, and not increased levels of experience dependent neuronal activity, promote barrel expansion in the primary somatosensory cortex of rats enucleated at birth. PMID:23372796

  5. Detection of Mycobacterium tuberculosis with nested polymerase chain reaction analysis in enucleated eye ball in Eales' disease.

    PubMed

    Verma, Aditya; Biswas, Jyotirmay; Dhanurekha, L; Gayathri, R; Lily Therese, K

    2016-06-01

    Nested polymerase chain reaction (nPCR) was performed on enucleated eyeball for detection of Mycobacterium tuberculosis (M. tb) genome in a patient with Eales' disease. PCR analysis in all previous studies has been done mainly using aqueous, vitreous and epiretinal membranes from these patients. Paraffin wax embedded tissue section of the enucleated eyeball was analyzed by histopathology and nPCR targeting MPB64 gene and IS6110 region of M. tb genome. Lymphocytic infiltration was seen in the vitreous, iris and the retinal tissue. Ziehl Neelsen stain was negative for acid fast bacilli. Caseation necrosis was not seen in any section. Agarose gel electrophoretogram showed positive results with 200 bp specific amplified product targeting MPB64 gene, whereas nPCR targeting IS6110 region was negative. Since biopsy proven M. tb is extremely difficult in ocular tissues due to extensive necrosis, the nPCR technique aided in the diagnosis. PMID:26499903

  6. Malignant melanoma of the eye: treatment of posterior uveal lesions by Co-60 plaque radiotherapy versus enucleation

    SciTech Connect

    Markoe, A.M.; Brady, L.W. Jr.; Shields, J.A.; Augsburger, J.J.; Micaily, B.; Damsker, J.I.; Day, J.L.; Gamel, J.W.

    1985-09-01

    Survival rates and visual acuity of 100 patients treated for posterior uveal malignant melanoma by cobalt-60 plaque radiotherapy were compared with 150 patients treated by enucleation for the same disease. Life-table comparisons of the entire group showed significant differences in survival rates, with plaque radiotherapy patients appearing to fare better. However, when patients with small or medium tumors were compared, only slight differences were seen, implying that criteria used to select patients for treatment may affect interpretation. The two groups were also compared using the Cox proportional hazards model, which predicts survival based on the impact of clinical variables. In this analysis, the survival rates of the plaque radiotherapy group were no worse than those of the enucleation group. The advantage of conservative therapy lies in the potential to preserve useful vision over a considerable time.

  7. Enucleation of large keratocystic odontogenic tumor at mandible via unilateral sagittal split osteotomy: a report of three cases

    PubMed Central

    Lee, Hyeong-Geun; Rhee, Seung-Hyun; Noh, Chung-Ah

    2015-01-01

    Keratocystic odontogenic tumor (KCOT) is a common benign tumor of osseous lesions in dental and maxillofacial practice. We describe three cases of large KCOT located in the posterior part of the mandible extending to the angle and ramus region, which were enucleated via sagittal split osteotomy (SSO) of the mandible. There are cases in which a conventional enucleation procedure does not ensure complete excision of the entire lesion without damage to vital structures like the inferior alveolar nerve. In such cases, a SSO approach could be a better choice than conventional methods. The purpose of this article is to describe our experience using unilateral mandibular SSO for removal of a KCOT from the mandible. PMID:26339581

  8. Ghrelin and obestatin inhibit enucleation-induced adrenocortical proliferation in the rat.

    PubMed

    Rucinski, Marcin; Trejter, Marcin; Ziolkowska, Agnieszka; Tyczewska, Marianna; Malendowicz, Ludwik K

    2010-05-01

    Studies involving the role of ghrelin (GHREL) in regulating the proliferative activity of various cell types have obtained variable results depending primarily on the experimental model applied. It was recently reported that neither GHREL nor obestatin (OBS) affected the proliferative activity of cultured rat adrenocortical cells. In view of the conflicting results, we investigated the effects of GHREL and OBS on the proliferative activity of rat adrenocortical cells in a model of bilateral enucleation-induced adrenocortical regeneration in the rat. Rats were sacrificed 5 or 8 days after surgery. Twenty-four hours before being sacrificed, the appropriate groups were infused with 3 nmol GHREL or OBS/100 g. The mitotic index was assessed using the stachmokinetic method with vincristine. In comparison with intact rats, expression levels of ppGHREL, BAX, JUN-B and JUN-C genes were notably higher in regenerating adrenals, and neither GHREL nor OBS infusion affected these levels. Expression levels of the GHS-R, GPR39v2 and FOS genes were affected neither by adrenal enucleation nor GHREL or OBS infusion. Expression of only two studied genes, GPR39v1 and EGR1, was regulated by OBS. In the regenerating adrenal glands, GPR39v1 and EGR1 mRNA levels were higher than the levels in intact animals. GHREL infusion had no effect while OBS infusion notably stimulated GPR39v1 mRNA levels in the regenerating adrenal gland and evoked an opposite effect on EGR1 mRNA. OBS administration resulted in a potent decrease in the mitotic index of the studied cells, an effect found at both days 5 and 8 of the experiment. GHREL exerted a similar effect only at day 5 of adrenocortical regeneration. Neither GHREL nor OBS had an effect on blood aldosterone concentrations. GHREL infusion lowered plasma corticosterone concentration at day 5 but not 8 of the experiment, while OBS administration was ineffective. Thus, this study is the first to demonstrate that, in vivo, both GHREL and OBS inhibit the

  9. In vivo cerebral incorporation of radiolabeled fatty acids after acute unilateral orbital enucleation in adult hooded Long-Evans rats

    SciTech Connect

    Wakabayashi, S.; Freed, L.M.; Bell, J.M.; Rapoport, S.I.

    1994-03-01

    We examined effects of acute unilateral enucleation on incorporation from blood of intravenously injected unsaturated [1-{sup 14}C]arachidonic acid ([{sup 14}C]AA) and [1-{sup 14}C]docosahexaenoic acid ([{sup 14}C]DHA), and of saturated [9,10-{sup 3}H]palmitic acid ([{sup 3}H]PA), into visual and nonvisual brain areas of awake adult Long-Evans hooded rats. Regional cerebral metabolic rate for glucose (rCMR{sub glc}) values also were assessed with 2-deoxy-D-[1-{sup 14}C]glucose ([{sup 14}C]DG). One day after unilateral enucleation, an awake rat was placed in a brightly lit visual stimulation box with black and white striped walls, and a radiolabeled fatty acid was infused for 5 min or [{sup 14}C]DG was injected as a bolus. [{sup 14}C]DG also was injected in a group of rats kept in the dark for 4 h. Fifteen minutes after starting an infusion of a radiolabeled fatty acid, or 45 min after injecting [{sup 14}C]DG, the rat was killed and the brain was prepared for quantitative autoradiography. Incorporation coefficients k* of fatty acids, or rCMR{sub glc} values, were calculated in homologous brain regions contralateral and ipsilateral to enucleation. As compared with ipsilateral regions, rCMR{sub glc} was reduced significantly (by as much as -39%) in contralateral visual areas, including the superior colliculus, lateral geniculate body, and layers I, IV, and V of the primary (striate) and secondary (association, extrastriate) visual cortices. These results indicate that enucleation acutely reduces neuronal activity in contralateral visual areas of the awake rat and that the reductions are coupled to reduced incorporation of unsaturated fatty acids into sn-2 regions of phosphatidylcholine, phosphatidylinositol, and phosphatidylethanolamine. Reduced fatty acid incorporation likely reflects reduced activity of phospholipases A{sub 2} and/or phospholipase C. 65 refs., 5 figs., 5 tabs.

  10. Results of the treatment of keratocystic odontogenic tumours using enucleation and treatment of the residual bony defect with Carnoy's solution.

    PubMed

    Leung, Y Y; Lau, S L; Tsoi, K Y Y; Ma, H L; Ng, C L

    2016-09-01

    This retrospective study aimed to investigate the recurrence rate of keratocystic odontogenic tumours (KCOTs) treated by enucleation and the application of Carnoy's solution, and to assess the surgical morbidities associated with this treatment. KCOTs treated using a standard protocol of enucleation and the application of Carnoy's solution between 1990 and 2013 were evaluated. One hundred and five KCOTS in 105 patients (54 male, 51 female) were analysed. The mean follow-up period was 86.6 months (range 24-313 months). The recurrence rate was 11.4%. A postoperative inferior alveolar nerve neurosensory deficit occurred in 30.1% of the mandibular cases, with 16% of these being permanent. The postoperative infection and fracture rates were 1.9% and 0.9%, respectively. Younger age, multilocular KCOTs, larger tumour size, and longer antero-posterior lesion length on the radiograph were found to be risk factors for recurrence. It is concluded that enucleation and the application of Carnoy's solution to treat KCOTs results in a relatively low recurrence rate and a low rate of surgical morbidities. PMID:26922497

  11. Ankyrin and band 3 differentially affect expression of membrane glycoproteins but are not required for erythroblast enucleation

    SciTech Connect

    Ji, Peng; Lodish, Harvey F.

    2012-01-27

    Highlights: Black-Right-Pointing-Pointer Ankyrin and band 3 are not required for erythroblasts enucleation. Black-Right-Pointing-Pointer Loss of ankyrin does not affect erythroid membrane glycoprotein expression. Black-Right-Pointing-Pointer Loss of band 3 influences erythroid membrane glycoprotein expression. -- Abstract: During late stages of mammalian erythropoiesis the nucleus undergoes chromatin condensation, migration to the plasma membrane, and extrusion from the cytoplasm surrounded by a segment of plasma membrane. Since nuclear condensation occurs in all vertebrates, mammalian erythroid membrane and cytoskeleton proteins were implicated as playing important roles in mediating the movement and extrusion of the nucleus. Here we use erythroid ankyrin deficient and band 3 knockout mouse models to show that band 3, but not ankyrin, plays an important role in regulating the level of erythroid cell membrane proteins, as evidenced by decreased cell surface expression of glycophorin A in band 3 knockout mice. However, neither band 3 nor ankyrin are required for enucleation. These results demonstrate that mammalian erythroblast enucleation does not depend on the membrane integrity generated by the ankyrin-band 3 complex.

  12. Enucleation-induced rat adrenal gland regeneration: expression profile of selected genes involved in control of adrenocortical cell proliferation.

    PubMed

    Tyczewska, Marianna; Rucinski, Marcin; Ziolkowska, Agnieszka; Szyszka, Marta; Trejter, Marcin; Hochol-Molenda, Anna; Nowak, Krzysztof W; Malendowicz, Ludwik K

    2014-01-01

    Enucleation-induced adrenal regeneration is a highly controlled process; however, only some elements involved in this process have been recognized. Therefore, we performed studies on regenerating rat adrenals. Microarray RNA analysis and QPCR revealed that enucleation resulted in a rapid elevation of expression of genes involved in response to wounding, defense response, and in immunological processes. Factors encoded by these genes obscure possible priming effects of various cytokines on initiation of regeneration. In regenerating adrenals we identified over 100 up- or downregulated genes involved in adrenocortical cell proliferation. The changes were most significant at days 2-3 after enucleation and their number decreased during regeneration. For example, expression analysis revealed a notable upregulation of the growth arrest gene, Gadd45, only 24 hours after surgery while expression of cyclin B1 and Cdk1 genes was notably elevated between days 1-8 of regeneration. These changes were accompanied by changes in expression levels of numerous growth factors and immediate-early transcription factors genes. Despite notable differences in mechanisms of adrenal and liver regeneration, in regenerating adrenals we identified genes, the expression of which is well recognized in regenerating liver. Thus, it seems legitimate to suggest that, in the rat, the general model of liver and adrenal regeneration demonstrate some degree of similarity. PMID:25431590

  13. Enucleation-Induced Rat Adrenal Gland Regeneration: Expression Profile of Selected Genes Involved in Control of Adrenocortical Cell Proliferation

    PubMed Central

    Tyczewska, Marianna; Rucinski, Marcin; Ziolkowska, Agnieszka; Szyszka, Marta; Trejter, Marcin; Hochol-Molenda, Anna; Nowak, Krzysztof W.; Malendowicz, Ludwik K.

    2014-01-01

    Enucleation-induced adrenal regeneration is a highly controlled process; however, only some elements involved in this process have been recognized. Therefore, we performed studies on regenerating rat adrenals. Microarray RNA analysis and QPCR revealed that enucleation resulted in a rapid elevation of expression of genes involved in response to wounding, defense response, and in immunological processes. Factors encoded by these genes obscure possible priming effects of various cytokines on initiation of regeneration. In regenerating adrenals we identified over 100 up- or downregulated genes involved in adrenocortical cell proliferation. The changes were most significant at days 2-3 after enucleation and their number decreased during regeneration. For example, expression analysis revealed a notable upregulation of the growth arrest gene, Gadd45, only 24 hours after surgery while expression of cyclin B1 and Cdk1 genes was notably elevated between days 1–8 of regeneration. These changes were accompanied by changes in expression levels of numerous growth factors and immediate-early transcription factors genes. Despite notable differences in mechanisms of adrenal and liver regeneration, in regenerating adrenals we identified genes, the expression of which is well recognized in regenerating liver. Thus, it seems legitimate to suggest that, in the rat, the general model of liver and adrenal regeneration demonstrate some degree of similarity. PMID:25431590

  14. Neuromedin-U stimulates enucleation-induced adrenocortical regeneration in the rat.

    PubMed

    Trejter, Marcin; Neri, Giuliano; Rucinski, Marcin; Majchrzak, Mariola; Nussdorfer, Gastone G; Malendowicz, Ludwik K

    2008-06-01

    Neuromedin-U (NMU) is a brain-gut peptide, which has been previously found to stimulate hypothalamic-pituitary-adrenal axis in the rat. Enucleation-induced adrenal regeneration in rats with contralateral adrenalectomy is a well-established model of adrenal growth, that not only depends on the compensatory ACTH hypersecretion, but is also modulated by several regulatory peptides. Hence, we investigated whether NMU may be included in this group of bioactive molecules. Reverse transcription-polymerase chain reaction and immunocytochemistry showed that regenerating rat adrenocortical cells at days 5 and 8 after surgery express the NMU receptor NMUR1 as mRNA and protein. NMU8 administration to rats bearing regenerating adrenals markedly raised the plasma concentration of corticosterone and notably enhanced proliferative activity of adrenocortical cells. ACTH blood level was unchanged at day 5 and significantly decreased at day 8. The conclusion is drawn that NMU stimulates regeneration of rat adrenal cortex, via a mechanism independent of pituitary ACTH and involving the activation of NMUR1 located on adrenocortical cells. PMID:18506360

  15. Orbital and Subcutaneous Emphysema Following Enucleation and Respiratory Distress in a Japanese Chin.

    PubMed

    Gornik, Kara R; Pirie, Christopher G; Alario, Anthony F

    2015-01-01

    A 7 yr old, neutered male Japanese chin presented to the Cummings School of Veterinary Medicine at Tufts University (CSVMTU) for evaluation of chronic unilateral orbital swelling that worsened following an episode of respiratory distress. The left eye had been enucleated 5 yr previously. Intermittent mild-to-moderate left orbital swelling had been noted by the owner since the initial surgery. Examination demonstrated a moderate-to-severe, soft, fluctuant swelling involving the left orbit with erythema of the overlying skin. Crepitus was noted over the occipital tuberosity. Computed tomography revealed a large volume of gas involving the left orbit. The gas extended caudally within the subcutaneous tissues to both hemimandibles, dorsal to the cranium, and partially surrounded the cranial neck. The presence of a mucosa-lined, air-filled space with a patent nasolacrimal duct was noted on orbital exploration. The lining was removed and the duct closed. Histopathology confirmed the presence of an epithelial lining. No recurrence of the swelling was observed on examination 8 wk after surgery. This is the first report documenting acute worsening of orbital swelling following an episode of respiratory distress. This case highlights the importance of addressing the nasolacrimal duct while performing an enculeation in a brachycephalic dog. PMID:26535462

  16. In vivo cerebral incorporation of radiolabeled fatty acids after acute unilateral orbital enucleation in adult hooded Long-Evans rats.

    PubMed

    Wakabayashi, S; Freed, L M; Bell, J M; Rapoport, S I

    1994-03-01

    We examined effects of acute unilateral enucleation on incorporation from blood of intravenously injected unsaturated [1-14C]arachidonic acid ([14C]AA) and [1-14C]docosahexaenoic acid ([14C]DHA), and of saturated [9,10-3H]palmitic acid ([3H]PA), into visual and nonvisual brain areas of awake adult Long-Evans hooded rats. Regional cerebral metabolic rate for glucose (rCMRglc) values also were assessed with 2-deoxy-D-[1-14C]glucose ([14C]DG). One day after unilateral enucleation, an awake rat was placed in a brightly lit visual stimulation box with black and white striped walls, and a radiolabeled fatty acid was infused for 5 min or [14C]DG was injected as a bolus. [14C]DG also was injected in a group of rats kept in the dark for 4 h. Fifteen minutes after starting an infusion of a radiolabeled fatty acid, or 45 min after injecting [14C]DG, the rat was killed and the brain was prepared for quantitative autoradiography. Incorporation coefficients k* of fatty acids, or rCMRglc values, were calculated in homologous brain regions contralateral and ipsilateral to enucleation. As compared with ipsilateral regions, rCMRglc was reduced significantly (by as much as -39%) in contralateral visual areas, including the superior colliculus, lateral geniculate body, and layers I, IV, and V of the primary (striate) and secondary (association, extrastriate) visual cortices. Enucleation did not affect incorporation of [3H]PA into contralateral visual regions, but reduced incorporation of [14C]AA and of [14C]DHA by -18.5 to -2.1%. Percent reductions were correlated with percent reductions in rCMRglc in most but not all regions. No effects were noted at any of nine non-visual structures that were examined. These results indicate that enucleation acutely reduces neuronal activity in contralateral visual areas of the awake rat and that the reductions are coupled to reduced incorporation of unsaturated fatty acids into sn-2 regions of phosphatidylcholine, phosphatidylinositol, and

  17. Globin synthesis in hybrid cells constructed by transplantation of dormant avian erythrocyte nuclei into enucleated fibroblasts.

    PubMed Central

    Bruno, J; Reich, N; Lucas, J J

    1981-01-01

    The polypeptides synthesized by mature embryonic erythrocytes prepared from the peripheral blood of 14- to 15-day-old chicken embryos were analyzed by two-dimensional gel electrophoresis. Fewer than 200 species of polypeptides were detected; the major polypeptides made at this time were identified as the alpha A-, alpha D-, and beta-globin chains. The dormant erythrocyte nuclei were next reactivated to transcriptional competence by transplantation into enucleated mouse or chicken embryo fibroblasts, with frequencies of cytoplast renucleation of about 50 and 90%, respectively. Since large numbers of hybrid cells could be constructed, a biochemical analysis was possible. Electrophoretic analysis of the [35S]methionine-labeled polypeptides made in the hybrid cell types showed that polypeptides having the mobilities of only two (alpha A and alpha D) of the three major adult globin chains were made as major constituents of the hybrid cells. However, analysis of 14C-amino acid-labeled polypeptides revealed that a beta-like polypeptide that lacked methionine was also synthesized in large amounts. This polypeptide was tentatively identified as the early embryonic globin species rho. Globin synthesis was detected as early as 3 h after nuclear transplantation and as late as 18 h, the last time measured in these experiments. It appeared that globin polypeptides made at very early times were translated at least partially from chicken messenger ribonucleic acid introduced into the hybrid cells during fusion, whereas those made at later times were translated primarily from newly synthesized globin messenger ribonucleic acid. The potential usefulness of this hybrid cell system in analyzing mechanisms regulating globin gene expression is discussed. Images PMID:7346715

  18. Spontaneous Bone Regeneration After Enucleation of Large Jaw Cysts: A Digital Radiographic Analysis of 44 Consecutive Cases

    PubMed Central

    Chacko, Rabin; Paul, Arun; Arvind

    2015-01-01

    Purpose This study evaluated the healing in cystic defect of the jaw to substantiate our understanding of spontaneous bone healing after enucleation of jaw cysts subjectively and with analysis of digital postoperative panoramic radiographs. Materials and Methods Fourty four consecutive patients reporting to the Department of Dental and Oral Surgery, during the period between 2008-2012 having maxillary and mandibular cysts treated by either surgical enucleation or by marsupialization followed by enucleation were evaluated for subsequent bone formation at the site of cystectomy defect by subjective clinical examination along with digital radiographic examination. Postoperative clinical and radiographic examinations were performed at 6,9,12, and 24 months. Bone regeneration was evaluated by reduction of the size of residual cavities at the cystectomy defect using digital orthopantomogram. Results Out of 44 patients 15 patients completed two years of follow-up with all the patients having 6 months follow-up. The maximum size of the cystic pathology was 150.40mm and minimum of 14.73mm at the time of presentation (average size of 58.16mm). Twenty patients were diagnosed with odontogenic keratocyst, with one patient having multiple OKC associated with Gorlin Goltz Syndrome, 17 patients had dentigerous cyst, 5 had Radicular cyst; solitary bone cyst and globulomaxillary cyst formed one each. Uneventful healing and spontaneous filling of the residual cavities were obtained in all cases. The digital analysis of the postoperative radiographs showed mean values of reduction in size of the residual cavity of 25.85% after 6 months, 57.13% after 9 months, 81.03% after one year and 100% after two year. Conclusion Spontaneous bone regeneration can occur after surgical removal of jaw cysts without the aid of any graft materials even in large cystic cavity sufficiently surrounded by enough bony walls. This simplifies the surgical procedure, decreases the overall cost of surgery, and

  19. Carprofen provides better post-operative analgesia than tramadol in dogs after enucleation: A randomized, masked clinical trial

    PubMed Central

    Delgado, Cherlene; Bentley, Ellison; Hetzel, Scott; Smith, Lesley J

    2015-01-01

    Objective To compare analgesia provided by carprofen or tramadol in dogs after enucleation. Design Randomized, masked trial Animals Forty-three dogs Procedures Client-owned dogs admitted for routine enucleation were randomly assigned to receive either carprofen or tramadol orally 2 hours prior to surgery and 12 hours after the first dose. Dogs were scored for pain at baseline, and postoperatively at 0.25, 0.5, 1, 2, 4, 6, 8, 24, and 30 hours after extubation. Dogs received identical premedication and inhalation anesthesia regimens, including premedication with hydromorphone. If the total pain score was ≥9, if there was a score ≥ 3 in any one category, or if the visual analog scale score (VAS) was ≥35 combined with a palpation score of >0, rescue analgesia (hydromorphone) was administered and treatment failure was recorded. Characteristics between groups were compared with a Student’s t-test and Fisher’s exact test. The incidence of rescue was compared between groups using a log rank test. Pain scores and VAS scores between groups were compared using repeated measures ANOVA. Results There was no difference in age (p=0.493), gender (p=0.366) or baseline pain scores (p=0.288) between groups. Significantly more dogs receiving tramadol required rescue analgesia (6/21) compared to dogs receiving carprofen (1/22; p=0.035). Pain and VAS scores decreased linearly over time (p=0.038, p<0.001, respectively). There were no significant differences in pain (p=0.915) or VAS scores (p=0.372) between groups at any time point (dogs were excluded from analysis after rescue). Conclusions and Clinical Relevance This study suggests that carprofen, with opioid premedication, provides more effective post-operative analgesia than tramadol in dogs undergoing enucleation. PMID:25459482

  20. Congenital Anophthalmia and Binocular Neonatal Enucleation Differently Affect the Proteome of Primary and Secondary Visual Cortices in Mice

    PubMed Central

    Smolders, Katrien; Hu, Tjing-Tjing; Bronchti, Gilles; Boire, Denis; Arckens, Lutgarde

    2016-01-01

    In blind individuals, visually deprived occipital areas are activated by non-visual stimuli. The extent of this cross-modal activation depends on the age at onset of blindness. Cross-modal inputs have access to several anatomical pathways to reactivate deprived visual areas. Ectopic cross-modal subcortical connections have been shown in anophthalmic animals but not in animals deprived of sight at a later age. Direct and indirect cross-modal cortical connections toward visual areas could also be involved, yet the number of neurons implicated is similar between blind mice and sighted controls. Changes at the axon terminal, dendritic spine or synaptic level are therefore expected upon loss of visual inputs. Here, the proteome of V1, V2M and V2L from P0-enucleated, anophthalmic and sighted mice, sharing a common genetic background (C57BL/6J x ZRDCT/An), was investigated by 2-D DIGE and Western analyses to identify molecular adaptations to enucleation and/or anophthalmia. Few proteins were differentially expressed in enucleated or anophthalmic mice in comparison to sighted mice. The loss of sight affected three pathways: metabolism, synaptic transmission and morphogenesis. Most changes were detected in V1, followed by V2M. Overall, cross-modal adaptations could be promoted in both models of early blindness but not through the exact same molecular strategy. A lower metabolic activity observed in visual areas of blind mice suggests that even if cross-modal inputs reactivate visual areas, they could remain suboptimally processed. PMID:27410964

  1. [History of laser in BPH therapy].

    PubMed

    Grande, Marco; Facchini, Francesco; Moretti, Matteo; Larosa, Michelangelo; Leone, Marco; Ziglioli, Francesco; Pozzoli, Gian Luigi; Frattini, Antonio

    2014-01-01

    Laser technology has been used in the treatment of BPH for more than 15-20 years in order to challenge transurethral resection of the prostate. The aim of this review article is to analyze the evolution of laser in BPH therapy, from early coagulative techniques - progressively abandoned for their elevated postoperative morbidity and unfavorable outcomes - to the newer techniques of vaporization, resection and enucleation of the prostate. A better comprehension of tissue-laser interactions, the improvement of laser technology and a growing clinical experience have lead to the development of different laser systems (Holmium, KTP, Thulium laser) that challenge TURP. Today, HoLEP and, secondarily, PVP are the laser techniques supported by more clinical evidences and represent valid alternatives to TURP. PMID:24665033

  2. Prosthetic Rehabilitation Following Socket Reconstruction with Blair-Brown Graft and Conformer Therapy for Management of Severe Post-Enucleation Socket Syndrome--A Clinical Report.

    PubMed

    Aggarwal, Himanshi; Singh, Saumyendra V; Kumar, Pradeep; Kumar Singh, Arun

    2015-06-01

    One of the most common tumors of the eye diagnosed in childhood is retinoblastoma, which mandates enucleation with adjunctive chemotherapy and radiotherapy to save the patient's life. The most common late enucleation complication is post-enucleation socket syndrome (PESS), which poses a management dilemma for the prosthodontist and surgeon, along with being a major esthetic concern for the patient. The reconstruction of such sockets is complex. The purpose of this clinical report is to describe the rehabilitation of such a pediatric patient with severe PESS. The patient was successfully rehabilitated by presurgical conformer therapy, socket reconstruction surgery with non-meshed intermediate split thickness skin graft (STSG)/Blair-Brown graft, and postsurgical conformer stent. This was followed by fabrication of a custom ocular prosthesis, to achieve favorable functional, physical, and psychological effects. PMID:25231188

  3. Development of inter-family nuclear transplant embryos by transplanting the nuclei from the loach blastulae into the non-enucleated zebrafish eggs

    NASA Astrophysics Data System (ADS)

    Li, Li; Zhang, Shicui; Yuan, Jinduo; Li, Hongyan

    2003-03-01

    The developmental fate of the pronuclei in recombined embryos obtained by transplanting the donor nuclei into the non-enucleated eggs remains controversial in the case of fish. In the present study, the nuclei from the loach blastulae were transplanted into non-enucleated zebrafish eggs, the resulting 9 inter-family nuclear transplant embryos developed to larval stages. Although the development timing of the nuclear transplants resembled that of zebrafish, chromosome examination revealed that most of the recombined embryos were diploids with karyotype characteristic of loach, which was also proved by RAPD analysis. Moreover, 3 out of the 9 larval fish formed barb rudiments specific to loach. It was therefore concluded that the nuclear transplant larval fish were inter-family nucleo-cytoplasmic hybrids; and that only the donor nuclei were involved in the development of the nuclear transplant embryos, while the pronuclei in the non-enucleated eggs were likely automatically eliminated during the development.

  4. Fertility and Pregnancy Outcome after Myoma Enucleation by Minilaparotomy under Microsurgical Conditions in Pronounced Uterus Myomatosus

    PubMed Central

    Floss, K.; Garcia-Rocha, G.-J.; Kundu, S.; von Kaisenberg, C. S.; Hillemanns, P.; Schippert, C.

    2015-01-01

    Introduction: Besides the typical complaints and symptoms, myomas can cause sterility, infertility and complications during pregnancy. Laparoscopic interventions reach their limits with regard to organ preservation and the simultaneous desire to have children in the removal of multiple and larger intramural myoma nodes. The aim of this study is to examine fertility status and pregnancy outcome after myoma removal by minilaparotomy (skin incision maximal 8 cm) in women with pronounced uterus myomatosus. Materials and Methods: This retrospective study makes use of the data from 160 patients with an average age of 34.6 years. Factors analysed include number, size and localisation of the myomas, complaints due to the myoma, pre- and postoperative gravidity, mode of delivery, and complications of birth. Results: Indications for organ-sparing myoma enucleation were the desire to have children (72.5 %), bleeding disorders (60 %) and pressure discomfort (36.5 %). On average 4.95 (SD ± 0.41), maximally 46 myomas were removed. The largest myoma had a diameter of 6.64 cm (SD ± 2.74). 82.5 % of the patients had transmural myomas, in 17.5 % the uterine cavity was inadvertently opened. On average the operating time was 163 minutes (SD ± 45.47), the blood loss 1.59 g/dL (SD ± 0.955). 60.3 % of the patients with the desire to have children became pregnant postoperatively. 75.3 % of the pregnancies were on average carried through to the 38th week (28.4 % vaginal deliveries, 71.6 % Caesarean sections). In the postoperative period there was one case of uterine rupture in the vicinity of a previous scar. Discussion: By means of the microsurgical “mini-laparotomy” even extensive myomatous uterine changes can, in the majority of cases, be operated in an organ-sparing manner with retention of the ability to conceive and to carry a pregnancy through to maturity of the infant. The risk for a postoperative uterine rupture in a subsequent pregnancy and

  5. Holmium laser for treatment of benign prostatic hyperplasia: old wine in a new bottle?

    NASA Astrophysics Data System (ADS)

    Nelius, Thomas; de Riese, Werner T. W.

    2003-06-01

    Urinary tract symptoms related to benign prostatic hyperplasia affect 70% of men older than 70 years. Complications are common problems and a significant cause of morbidity in this population, placing a considerable burden on health services. In the early 1990s laser treatment of benign prostatic hyperplasia became widely used after the introduction of the side-firing neodym: YAG laser. However, because of technical limitations and inferior results compared to classical transurethral resection of the prostate many Urologists became desinterested in this device. With the introduction of the holmium: YAG laser a new laser generation became available for use in Urology. Beside several other applications the holmium: YAG laser can be used for incision, ablation, resection, and more recently enucleation of the prostate. In this paper we reviewed the current literature regarding the holmium: YAG laser resection and enucleation of the prostate compared to transurethral resection of the prostate and open prostatectomy. The holmium: YAG laser technique is an effective and durable surgical alternative to standard transurethral resection of the prostate. Interestingly, enucleation of the prostate with this device seems to be a safe and effective procedure for large prostatic adenomas, it may become an attractive alternative to open prostatectomy.

  6. Rat Blastocysts from Nuclear Injection and Time-Lagged Enucleation and Their Commitment to Embryonic Stem Cells.

    PubMed

    Hara, Hiromasa; Goto, Teppei; Takizawa, Akiko; Sanbo, Makoto; Jacob, Howard J; Kobayashi, Toshihiro; Nakauchi, Hiromitsu; Hochi, Shinichi; Hirabayashi, Masumi

    2016-04-01

    Pronucleus-like vesicle formation following premature chromosome condensation (PCC) of the donor cell nucleus is the key event for successful generation of cloned rodents by nuclear transplantation (NT). However in rat cloning, this change is difficult to induce in enucleated recipient oocytes because of their inability to maintain maturation-promoting factor levels. In this study, intact oocytes retrieved from nuclear-visualized H2B-tdTomato knock-in rats were injected with Venus-labeled cell nuclei. Because the incidence of PCC under MG-132 treatment significantly increased with the culture period (0%, 10.8%, 36.8%, and 87.5% at 0, 0.5, 1, and 2 h postinjection, respectively), the metaphase plate of the oocyte was removed 1-2 h after the nuclear injection. The NT-derived rat zygotes (n = 748) were activated with ionomycin/cycloheximide and transferred into temporal host mothers, resulting in the harvest of three blastocysts (0.4%) with Venus fluorescence. Two blastocysts were examined for their potential to commit to NT-derived embryonic stem cells (ntESCs). One ntESC line was established successfully and found to be competent in terms of karyotype, stem cell marker expression, and pluripotency. In conclusion, time-lagged enucleation of visualized oocyte nuclei allows the PCC incidence of donor nuclei and generation of NT blastocysts, and the blastocysts can commit to germline-competent ntESCs. PMID:26990947

  7. New techniques for laser prostatectomy: an update

    PubMed Central

    Chung, Doreen E.; Te, Alexis E.

    2009-01-01

    Traditionally, the gold standard for treatment of BPH has been the electrocautery-based TransUrethral Resection of the Prostate (TURP). However, the number of laser techniques being performed is rapidly increasing. Potential advantages of laser therapy over traditional TURP include decreased morbidity and shorter hospital stay. There are several techniques for laser prostatectomy that continue to evolve. The main competing techniques are currently the Holmium Laser Enucleation of the Prostate (HoLEP) and the 80W 532nm laser prostatectomy. The HoLEP, using the Holmium:YAG laser, has been shown to have clinical results similar to TURP and is suitable for patients on anticoagulation as well as those with large prostates. Disadvantages of this technique are the high learning curve and requirement of a morcellator. When used to treat BPH, studies have demonstrated that, like the HoLEP, the 80W KTP laser is safe and effective in patients with large prostates and in those taking oral anticoagulation. Several studies have compared these two techniques to TURP. Frequently reported advantages of the HoLEP over the 80W laser prostatectomy are the availability after the procedure of a pathology specimen and ability to remove a higher percentage of prostate tissue during resection. However, the transurethral laser enucleation of the prostate addresses these concerns and has shown to have durable outcomes at 2-year follow-up. Two new laser systems and techniques, the thulium laser and the 980nm laser, have emerged recently. However, clinical data from these procedures are in their infancy and large long-term studies are required. PMID:21789057

  8. Modified endoscopic submucosal dissection with enucleation for treatment of gastric subepithelial tumors originating from the muscularis propria layer

    PubMed Central

    2012-01-01

    Background Gastric subepithelial tumors are usually asymptomatic and observed incidentally during endoscopic examination. Although most of these tumors are considered benign, some have a potential for malignant transformation, particularly those originating from the muscularis propria layer. For this type of tumor, surgical resection is the standard treatment of choice. With recent advent of endoscopic resection techniques and devices, endoscopic submucosal dissection (ESD) has been considered as an alternative way of treatment. The aim of this study is to demonstrate the feasibility of a modified ESD technique with enucleation for removal of gastric subepithelial tumors originating from the muscularis propria layer, and to evaluate its efficacy and safety. Methods From November 2009 to May 2011, a total of 16 patients received a modified ESD with enucleation for their subepithelial tumors. All tumors were smaller than 5 cm and originated from the muscularis propria layer of the stomach, as shown by endoscopic ultrasonography (EUS). The procedure was conducted with an insulated-tip knife 2. Patient’s demographics, tumor size and pathological diagnosis, procedure time, procedure-related complication, and treatment outcome were reviewed. Results Fifteen of the sixteen tumors were successful complete resection. The mean tumor size measured by EUS was 26.1 mm (range: 20–42 mm). The mean procedure time was 52 minutes (range: 30–120 minutes). Endoscopic features of the 4 tumors were pedunculated and 12 were sessile. Their immunohistochemical diagnosis was c-kit (+) stromal tumor in 14 patients and leiomyoma in 2 patients. There was no procedure-related perforation or overt bleeding. During a mean follow up duration of 14.8 months (range: 6–22 months), there was no tumor recurrence or metastasis. Conclusions Using a modified ESD with enucleation for treatment of gastric subepithelial tumors originating from the muscularis propria layer and larger

  9. Expression of selected genes involved in steroidogenesis in the course of enucleation-induced rat adrenal regeneration.

    PubMed

    Tyczewska, Marianna; Rucinski, Marcin; Ziolkowska, Agnieszka; Trejter, Marcin; Szyszka, Marta; Malendowicz, Ludwik K

    2014-03-01

    The enucleation-induced (EI) rapid proliferation of adrenocortical cells is followed by their differentiation, the degree of which may be characterized by the expression of genes directly and indirectly involved in steroid hormone biosynthesis. In this study, out of 30,000 transcripts of genes identified by means of Affymetrix Rat Gene 1.1 ST Array, we aimed to select genes (either up- or downregulated) involved in steroidogenesis in the course of enucleation-induced adrenal regeneration. On day 1, we found 32 genes with altered expression levels, 15 were upregulated and 17 were downregulated [i.e., 3β-hydroxysteroid dehydrogenase (Hsd3β), nuclear receptor subfamily 0, group B, member 1 (Nr0b1), cytochrome P450 aldosterone synthase (Cyp11b2) and sterol O-acyltransferase 1 (Soat1)]. On day 15, the expression of only 2 genes was increased and that of 3 was decreased. The investigated genes were clustered according to an hierarchical clustering algorithm and 4 clusters were obtained. Quantitative PCR (qPCR) confirmed the much lower mRNA expression levels of steroidogenic acute regulatory protein (StAR) during the regeneration process compared to the control, while the cholesterol side-chain cleavage enzyme (cholesterol desmolase; Cyp11a1) and Hsd3β genes presented similar expression profiles throughout the entire regeneration process. Cyp11b2 mRNA levels remained very low during the whole regeneration period. Fatty acid binding protein 6 (Fabp6) was markedly upregulated, whereas hormone-sensitive lipase (Lipe) was downregulated. The expression of Soat1 was lowest on regeneration day 1 and, subsequently, its expression increased from there on, reaching levels higher than the control. Dosage-sensitive sex reversal, adrenal hypoplasia critical region, on chromosome X, gene 1 (Dax-1) mRNA levels were lowest on day 1 of the experiment; however, throughout the entire experimental period, there were no statistically significant differences observed. After the initial

  10. Laser therapy in intraocular tumors

    NASA Astrophysics Data System (ADS)

    Carstocea, Benone D.; Gafencu, Otilia L.; Apostol, Silvia

    1995-01-01

    Intraocular tumors present special problems of diagnosis and treatment. Diagnostic methods include, in addition to systemic and ophthalmological examinations, ancillary examinations such as transillumination, fluorescein angiography, ultrasonography, radioactive phosphorus uptake test, radiology, computerized tomography, and fine-needle aspiration biopsy with cytological analyses. Previously, enucleation of the involved eye was generally accepted as management of malignant tumors. Improved therapeutic methods such as photocoagulation and better surgical techniques now provide a variety of therapeutical alternatives. This study consists of 21 cases of intraocular tumors that were managed by Argon laser photocoagulation. Four cases were intraocular metastasis and 17 cases were primitive intraocular tumors. Argon laser therapy proved to be totally ineffective for the intraocular metastasis and a very adequate therapy for the primitive tumors. Tumor extirpations (choroidal, cillary body, or iris tumors) using laser lancet proved to be more suitable than classic surgery.

  11. Against the motion: Lasers are superfluous for the surgical management of benign prostatic hyperplasia in the developing world.

    PubMed

    Varshney, Anil; Agarwal, Anshuman

    2009-07-01

    Lasers have arrived in a big way for the management of benign prostatic hyperplasia. The most common ones in use are holmium, potassium titanyl phosphate (KTP) and thulium.They remove the prostatic adenoma either by way of enucleation or ablation. Backed by numerous studies that prove their safety, efficacy and durability, lasers score over TURP in several ways. Their use is associated with less blood loss, shorter catheter time and decreased hospital stay. The fluid absorption during laser prostatectomy is negligible and thus makes it safer for use in cardiac patients. Also there is no chance of a transurethral resection syndrome, the incidence of which is approximately 2% with TURP. Due to superior hemostatic capabilities and non interference lasers can be used in patients on anti coagulants, cardiac pacemaker. Another advantage of laser over TURP is its ability to deal with prostates that are larger in size especially holmium laser which has been used to enucleate glands more than 300 g in size thus completely avoiding the need for open prostatectomy. The amount of tissue removed with enucleation is more thus retreatment rates are less than that of TURP. The initial cost of laser is higher but its capability to treat stones, its use in high risk situations, less morbidity, short hospital stay, and durable results make it an attractive option to treat BPH even in the developing world. PMID:19881144

  12. Outflow facility efficacy of five drugs in enucleated porcine eyes by a method of constant-pressure perfusion

    PubMed Central

    Li, Ning; Shi, Hui-Min; Cong, Lin; Lu, Zhao-Zeng; Ye, Wen; Zhang, Yu-Yan

    2015-01-01

    This study aimed to characterize a technique that assesses the outflow facility (C) efficacy of five kinds of IOP-lowering drugs commonly used clinically in enucleated porcine Eyes. Eyes were perfused at 15 mmHg with GPBS first to establish the baseline outflow facility (C0). Then the anterior chamber contents were exchanged for GPBS with corresponding concentration eye drops (4.9×103 nM Brimonidine, 41.1 nM Latanoprost, 3.4×103 nM Levobunolol, 3.0×103 nM Brinzolamide, 8.3×103 nM Pilocarpine) in five groups (n = 6 each), while 6 eyes received GPBS alone as control. The mean stable facility obtained after drug administration (C1) was continuously recorded. The changes between C0 and C1 (ΔC = C1-C0) were analyzed. Finally, for drugs among the five experiment groups with statistical significance, the concentration was reduced 3 times, otherwise the drugs’ concentration was increased to 10 times to confirm its effectiveness further using the same methods (n = 6 each). We found that the average baseline outflow facility was 0.24±0.01 μl·min-1·mmHg-1. C increased significantly in Brimonidine and Latanoprost groups, even the concentration of Brimonidine and Latanoprost was decreased 3 times (P < 0.05). However, there was no significantly increase in Levobunolol, Brinzolamide, Pilocarpine and control group (P > 0.05), but when drugs’ concentration was increased to 10 times, the C value of Pilocarpine decreased significantly (P = 0.04). No significant washout effects in porcine eyes were observed. To conclude, outflow facility efficacy of five drugs in enucleated porcine eyes may provide a reference for clinical medicine. A constant-pressure perfusion technique should be useful to evaluate effect of pharmacologic agents or surgical manipulations on aqueous humor dynamics. PMID:26221257

  13. Outflow facility efficacy of five drugs in enucleated porcine eyes by a method of constant-pressure perfusion.

    PubMed

    Li, Ning; Shi, Hui-Min; Cong, Lin; Lu, Zhao-Zeng; Ye, Wen; Zhang, Yu-Yan

    2015-01-01

    This study aimed to characterize a technique that assesses the outflow facility (C) efficacy of five kinds of IOP-lowering drugs commonly used clinically in enucleated porcine Eyes. Eyes were perfused at 15 mmHg with GPBS first to establish the baseline outflow facility (C0). Then the anterior chamber contents were exchanged for GPBS with corresponding concentration eye drops (4.9×10(3) nM Brimonidine, 41.1 nM Latanoprost, 3.4×10(3) nM Levobunolol, 3.0×10(3) nM Brinzolamide, 8.3×10(3) nM Pilocarpine) in five groups (n = 6 each), while 6 eyes received GPBS alone as control. The mean stable facility obtained after drug administration (C1) was continuously recorded. The changes between C0 and C1 (ΔC = C1-C0) were analyzed. Finally, for drugs among the five experiment groups with statistical significance, the concentration was reduced 3 times, otherwise the drugs' concentration was increased to 10 times to confirm its effectiveness further using the same methods (n = 6 each). We found that the average baseline outflow facility was 0.24±0.01 μl·min(-1)·mmHg(-1). C increased significantly in Brimonidine and Latanoprost groups, even the concentration of Brimonidine and Latanoprost was decreased 3 times (P < 0.05). However, there was no significantly increase in Levobunolol, Brinzolamide, Pilocarpine and control group (P > 0.05), but when drugs' concentration was increased to 10 times, the C value of Pilocarpine decreased significantly (P = 0.04). No significant washout effects in porcine eyes were observed. To conclude, outflow facility efficacy of five drugs in enucleated porcine eyes may provide a reference for clinical medicine. A constant-pressure perfusion technique should be useful to evaluate effect of pharmacologic agents or surgical manipulations on aqueous humor dynamics. PMID:26221257

  14. RNA-Seq Profiling of Intact and Enucleated Oocyte SCNT Embryos Reveals the Role of Pig Oocyte Nucleus in Somatic Reprogramming.

    PubMed

    Bai, Lin; Li, Mengqi; Sun, Junli; Yang, Xiaogan; Lu, Yangqing; Lu, Shengsheng; Lu, Kehuan

    2016-01-01

    The specific molecular mechanisms involved in somatic reprogramming remain unidentified. Removal of the oocyte genome is one of the primary causes of developmental failure in cloned embryos, whereas intact oocyte shows stronger reprogramming capability than enucleated oocyte. To identify the reason for the low efficiency of cloning and elucidate the mechanisms involved in somatic reprogramming by the oocyte nucleus, we injected pig cumulus cells into 539 intact MII oocytes and 461 enucleated MII oocytes. Following activation, 260 polyploidy embryos developed to the blastocyst stage whereas only 93 traditionally cloned embryos (48.2% vs. 20.2%, P < 0.01) reached blastocyst stage. Blastocysts generated from intact oocytes also had more cells than those generated from enucleated oocytes (60.70 vs. 46.65, P < 0.01). To identify the genes that contribute to this phenomenon, two early embryos in 2-cell and 4-cell stages were collected for single-cell RNA sequencing. The two kinds of embryos were found to have dramatically different transcriptome profiles. Intact oocyte nuclear transfer embryos showed 1,738 transcripts that were up-regulated relative to enucleated cloned embryos at the 2-cell stage and 728 transcripts that were down-regulated (|log2Ratio| ≥ 5). They showed 2,941 transcripts that were up-regulated during the 4-cell stage and 1,682 that were down-regulated (|log2Ratio| ≥ 5). The most significantly enriched gene ontology categories were those involved in the regulation of binding, catalytic activity, and molecular transducer activity. Other genes that were notably up-regulated and expressed in intact oocyte nuclear transfer embryos were metabolic process. This study provides a comprehensive profile of the differences in gene expression between intact oocyte nuclear transfer embryos and traditional nuclear transfer embryos. This work thus paves the way for further research on the mechanisms underlying somatic reprogramming by oocytes. PMID:27070804

  15. RNA-Seq Profiling of Intact and Enucleated Oocyte SCNT Embryos Reveals the Role of Pig Oocyte Nucleus in Somatic Reprogramming

    PubMed Central

    Bai, Lin; Li, Mengqi; Sun, Junli; Yang, Xiaogan; Lu, Yangqing; Lu, Shengsheng; Lu, Kehuan

    2016-01-01

    The specific molecular mechanisms involved in somatic reprogramming remain unidentified. Removal of the oocyte genome is one of the primary causes of developmental failure in cloned embryos, whereas intact oocyte shows stronger reprogramming capability than enucleated oocyte. To identify the reason for the low efficiency of cloning and elucidate the mechanisms involved in somatic reprogramming by the oocyte nucleus, we injected pig cumulus cells into 539 intact MII oocytes and 461 enucleated MII oocytes. Following activation, 260 polyploidy embryos developed to the blastocyst stage whereas only 93 traditionally cloned embryos (48.2% vs. 20.2%, P < 0.01) reached blastocyst stage. Blastocysts generated from intact oocytes also had more cells than those generated from enucleated oocytes (60.70 vs. 46.65, P < 0.01). To identify the genes that contribute to this phenomenon, two early embryos in 2-cell and 4-cell stages were collected for single-cell RNA sequencing. The two kinds of embryos were found to have dramatically different transcriptome profiles. Intact oocyte nuclear transfer embryos showed 1,738 transcripts that were up-regulated relative to enucleated cloned embryos at the 2-cell stage and 728 transcripts that were down-regulated (|log2Ratio| ≥ 5). They showed 2,941 transcripts that were up-regulated during the 4-cell stage and 1,682 that were down-regulated (|log2Ratio| ≥ 5). The most significantly enriched gene ontology categories were those involved in the regulation of binding, catalytic activity, and molecular transducer activity. Other genes that were notably up-regulated and expressed in intact oocyte nuclear transfer embryos were metabolic process. This study provides a comprehensive profile of the differences in gene expression between intact oocyte nuclear transfer embryos and traditional nuclear transfer embryos. This work thus paves the way for further research on the mechanisms underlying somatic reprogramming by oocytes. PMID:27070804

  16. Angiogenesis in the course of enucleation-induced adrenal regeneration--expression of selected genes and proteins involved in development of capillaries.

    PubMed

    Tyczewska, Marianna; Rucinski, Marcin; Trejter, Marcin; Ziolkowska, Agnieszka; Szyszka, Marta; Malendowicz, Ludwik K

    2012-12-01

    Enucleation-induced rapid proliferation of adrenocortical cells and restoration of adrenals structure requires formation of new blood vessels. The performed studies aimed to select from around 30,000 transcripts, identified by means of Affymetrix(®) Rat Gene 1.1 ST Array, the genes involved in angiogenesis in the course of enucleation-induced adrenal regeneration and to characterize their expression levels in regenerating gland between days 1 and 15 after surgery. At day 1 of regeneration almost 2000 genes showed more than 2-fold up/down-regulation. At days 1-3 after surgery the highest expression demonstrated genes involved in the development of inflammation and blood clot formation. From around 2000 genes we selected genes involved in angiogenesis. During the regeneration 62 genes involved in angiogenesis were identified as up- or down-regulated. Some data were also validated by QPCR. Levels of Vegfa and Kdr (Vegfr-2) mRNAs were very low at day 1 of regeneration and remained unchanged thereafter. The highest expression of Figf gene was found at day 5 while that of Vwf gene at days 1 and 2 after surgery. Levels of Thy1 mRNA increased notably between days 2 and 5 of the experiment. In comparison to control rats, Mc2r (ACTH receptor) expression was lowered at day 1 of the experiment and remained unchanged thereafter. This suggests that enucleation-induced adrenal neoangiogenesis does not require elevated expression of ACTH receptor. Results of our studies strongly suggest that enucleation-induced adrenal regeneration is an angiogenesis-dependent process. Moreover, immunohistochemistry suggests that regenerating adrenal parenchymal cells release numerous angiogenic factors which paracrinally may regulate formation of new vessels. PMID:23041583

  17. Reconstruction of severe anophthalmic orbits and atresic eye sockets after enucleation and irradiation of retinoblastoma by vascular anastomosed free dorsalis pedis flaps' transplantation.

    PubMed

    Bi, Xiaoping; Fan, Xianqun; Zhou, Huifang; Shi, Wodong; Xiao, Caiwen; Lin, Min; Li, Zhenkang

    2011-05-01

    Retinoblastoma is a common malignant intraocular tumor in childhood, and most patients require enucleation or exenteration even with irradiation. Severe anophthalmic orbits and atresic eye sockets are not rare. We conducted a retrospective study to evaluate the results of surgical management of reconstruction of severe anophthalmic orbits and atresic eye sockets with vascular anastomosed free dorsalis pedis flap transplantation. There were 5 patients (5 eyes) who underwent reconstructive surgery of severe anophthalmic orbits and atresic eye sockets after enucleation and irradiation of retinoblastoma in our hospital during the 3 years. All patients had enucleation and irradiation immediately after the retinoblastoma was diagnosed and had never worn artificial eyes because of the atresic eye sockets. Vascular anastomosed free dorsalis pedis flaps, whose dimensions were typically 6.5 × 5.5 cm(2), were transplanted to reconstruct the severe anophthalmic orbits and atresic eye sockets. The donor sites were covered by free abdominal skin flaps. All the vascular anastomosed free dorsalis pedis flaps were valid after more than 6 months of follow-up. And then all the 5 patients underwent secondary autogenous dermal fat implantation to augment the supraorbital area depression. After the 2-stage reconstruction surgery, the dimensions of the eye sockets were adequate, and all patients were able to wear their prosthesis and had a satisfactory cosmetic result. Implantation of alloplastic materials is not recommended because of insufficient blood supply of the irradiated orbital area. PMID:21558948

  18. Ultrasonographic determination of the dimensions of ocular components in enucleated eyes of the one-humped camel (Camelus dromedarius).

    PubMed

    Osuobeni, E P; Hamidzada, W A

    1999-10-01

    The refractive status and visual capabilities of the one-humped camel are not currently known. Schematic eyes are important tools in studying the optical characteristics and refractive status of an eye. The variables required in developing a schematic eye for a particular animal species include the dimensions of the optical components. We have employed A-scan ultrasonography to measure the dimensions of optical components in freshly enucleated eyes of the one-humped camel. Measurements were made in eyes immersed in distilled water kept at 20 degrees C. The average values of the optical components were as follows: anterior chamber depth = 5.27 mm, lens thickness = 10.93 mm, vitreous chamber depth = 14.85 mm and axial length = 31.05 mm. The uncorrected average corneal thickness was 0.76 mm. These values would have to be confirmed in live animal subjects before they can be used to design a schematic eye for the one-humped camel. PMID:10502480

  19. Inhibition of secondary cartilage of the intermaxillary suture in Sprague-Dawley rats following the enucleation of maxillary molars

    SciTech Connect

    Forbes, D.P.; Al-Bareedi, S.

    1986-01-01

    A single craniofacial suture can undergo several morphologic transformations during its development. From 3 to 7 weeks of age, the intermaxillary suture of the rat is synchondrotic in character, featuring secondary cartilage; at later times, this suture is syndesmotic in character, featuring a fibrous tissue interface. Since intermittent mechanical stimulation has been reported to initiate secondary cartilage formation, a study was done to determine if the functioning dentition were responsible for secondary cartilage formation in the intermaxillary suture of the rat. Twenty-two female Sprague-Dawley rats were used. At 3 weeks of age, prior to eruption, the maxillary molars were enucleated from nine animals. Body weights were recorded weekly. Animals were sacrificed weekly from 4 to 7 weeks of age. One hour prior to sacrifice, each rat was injected with (/sup 35/S)sulfate at a dosage of 2 microCi/g body weight. The tissues were evaluated by light microscopy and autoradiography. In the experimental group, the midpalatal suture did not undergo the normal synchondrotic transformation. Instead, this suture remained fibrous with negligible metachromatic staining. In the control animals, the peak period of (/sup 35/S)sulfate incorporation was 4 weeks of age and was five times greater than in the experimental group. The primary stimulus for the initiation of secondary cartilage formation in the midpalatal suture of the rat was molar function. Also, functioning molars were found to be important in the maintenance of the palatal bone.

  20. Different lasers in the treatment of benign prostatic hyperplasia: a network meta-analysis.

    PubMed

    Zhang, Xingming; Shen, Pengfei; He, Qiying; Yin, Xiaoxue; Chen, Zhibin; Gui, Haojun; Shu, Kunpeng; Tang, Qidun; Yang, Yaojing; Pan, Xiuyi; Wang, Jia; Chen, Ni; Zeng, Hao

    2016-01-01

    All available surgical treatments for benign prostatic hyperplasia (BPH) have their individual advantages or disadvantages. However, the lack of head-to-head studies comparing different surgeries makes it unavailable to conduct direct analysis. To compare the efficacy and safety among different lasers and transurethral resection of prostate (TURP) for BPH, randomized controlled trials were searched in MEDLINE, EMBASE, Cochrane library, WHO International Clinical Trial Registration Platform, and Clinical Trial.gov by 2015.5; and the effectiveness-, perioperation- and complication-related outcomes were assessed by network meta-analysis. 36 studies involving 3831 patients were included. Holmium laser through resection and enucleation had the best efficacy in maximum flow rate. Thulium laser through vapo-resection was superior in improving international prostate symptom score and holmium laser through enucleation was the best for post-voiding residual volume improvement. Diode laser through vaporization was the rapidest in removing postoperative indwelling catheter, while TURP was the longest. TURP required the longest hospitalization and thulium laser through vapo-resection was relatively shorter. Holmium and thulium lasers seem to be relatively better in surgical efficacy and safety, so that these two lasers might be preferred in selection of optimal laser surgery. Actually, more large-scale and high quality head-to-head RCTs are suggested to validate the conclusions. PMID:27009501

  1. Different lasers in the treatment of benign prostatic hyperplasia: a network meta-analysis

    PubMed Central

    Zhang, Xingming; Shen, Pengfei; He, Qiying; Yin, Xiaoxue; Chen, Zhibin; Gui, Haojun; Shu, Kunpeng; Tang, Qidun; Yang, Yaojing; Pan, Xiuyi; Wang, Jia; Chen, Ni; Zeng, Hao

    2016-01-01

    All available surgical treatments for benign prostatic hyperplasia (BPH) have their individual advantages or disadvantages. However, the lack of head-to-head studies comparing different surgeries makes it unavailable to conduct direct analysis. To compare the efficacy and safety among different lasers and transurethral resection of prostate (TURP) for BPH, randomized controlled trials were searched in MEDLINE, EMBASE, Cochrane library, WHO International Clinical Trial Registration Platform, and Clinical Trial.gov by 2015.5; and the effectiveness-, perioperation- and complication-related outcomes were assessed by network meta-analysis. 36 studies involving 3831 patients were included. Holmium laser through resection and enucleation had the best efficacy in maximum flow rate. Thulium laser through vapo-resection was superior in improving international prostate symptom score and holmium laser through enucleation was the best for post-voiding residual volume improvement. Diode laser through vaporization was the rapidest in removing postoperative indwelling catheter, while TURP was the longest. TURP required the longest hospitalization and thulium laser through vapo-resection was relatively shorter. Holmium and thulium lasers seem to be relatively better in surgical efficacy and safety, so that these two lasers might be preferred in selection of optimal laser surgery. Actually, more large-scale and high quality head-to-head RCTs are suggested to validate the conclusions. PMID:27009501

  2. The role of lasers in modern urology

    PubMed Central

    Dołowy, Łukasz; Dembowski, Janusz; Zdrojowy, Romuald; Kołodziej, Anna

    2015-01-01

    Introduction The functioning of modern urological departments and the high level of service they provide is possible through, among other things, the use of modern laser techniques. Material and methods Open operations have been replaced by minimally invasive procedures, and classical surgical tools by advanced lasers. The search for new applications with lasers began as technology developed. Among many devices available, holmium, diode and thulium lasers are currently the most popular. Results Depending on the wavelength, the absorption by water and hemoglobin and the depth of penetration, lasers can be used for coagulation, vaporization and enucleation. In many centres, after all the possibilities of pharmacological treatment have been exhausted, lasers are used as the primary treatment for patients with benign prostatic hyperplasia, with therapeutic results that are better than those obtained through open or endoscopic operations. The use of lasers in the treatment of urolithiasis, urinary strictures and bladder tumours has made treatment of older patients with multiple comorbidities safe, without further necessity to modify the anticoagulant drug treatment. Laser procedures are additionally less invasive, reduce hospitalization time and enable a shorter bladder catheterization time, sometimes even eliminating the need for bladder catherterization completely. Such procedures are also characterized by more stable outcomes and a lower number of reoperations. Conclusions There are also indications that with the increased competition among laser manufacturers, decreased purchase and maintenance costs, and increased operational safety, laser equipment will become mandatory and indispensable asset in all urology wards. PMID:26251737

  3. Laser therapy in ocular tumors

    NASA Astrophysics Data System (ADS)

    Carstocea, Benone D.; Gafencu, Otilia L.; Apostol, Silvia; Ionita, Marcel A.; Moroseanu, A.; Dascalu, Traian; Lupei, Voicu; Ionita-Manzatu, V.

    1998-07-01

    The medical laser equipments made at NILPRP have been exploited intensively for more than 10 years at CMH. The availability and reliability of the first like-on equipment have increased, following improvements in optical delivery system and cooling circuit. This paper shows the impact of technical advances on the development of ophthalmologic laser therapy. Intraocular tumors pose special problems of diagnosis and treatment. Diagnostic methods include addition to systemic and ophthalmologic examinations, ancillary examinations, such as transillumination, fluorescence angiography, ultrasonography, radioactive phosphorus uptake tests, radiology, computerized tomography and fine-needle aspiration biopsy with cytological analyses. The enucleation of the involved eye used to be a generally accepted management of malignant tumors. Improved therapeutic methods such as photocoagulation and better surgical techniques now provide a variety of therapeutic alternatives. This study covers 31 cases of intraocular tumors that were managed either by Argon Laser photocoagulation and/or by Nd:YAG laser surgical treatment. Four cases were intraocular metastasse and 17 cases were primitive intraocular tumors. Argon laser therapy proved to be totally ineffective for intraocular metastasse but very adequate therapy for primitive tumors. Tumor extirpations (choroidal, cillary body or iris tumors) using Nd:YAG laser lancet proved to be more suitable than classic surgery.

  4. Best laser for prostatectomy in the year 2013

    PubMed Central

    Maheshwari, Pankaj N; Joshi, Nitin; Maheshwari, Reeta P

    2013-01-01

    Lasers have come a long way in the management of benign prostatic hyperplasia. Over last nearly two decades, various different lasers have been utilized for prostatectomy. Neodymium: yttrium-aluminum-garnet laser that started this journey, is no longer used for prostatectomy. Holmium laser can achieve transurethral enucleation of the prostatic adenoma producing a fossa that can be compared with the fossa after Freyer's prostatectomy. Green light laser has a short learning curve, is nearly blood-less with good immediate results. Thulium laser is a faster cutting laser while diode laser is a portable laser device. Often laser prostatectomy is considered as a replacement for the standard transurethral resection of prostate (TURP). To be comparable, laser should reduce or avoid the immediate and long-term complications of TURP, especially bleeding and need for blood transfusion. It should also be safe in the ever increasing patient population on antiplatelet and anticoagulant drugs. We need to take stock of the situation and identify, which among the present day lasers has stood the test of time. A review of the literature was performed to see if any of these lasers could be called the “best laser for prostatectomy in 2013.” PMID:24082446

  5. Endoscopic Enucleation versus Open Prostatectomy for Treating Large Benign Prostatic Hyperplasia: A Meta-Analysis of Randomized Controlled Trials

    PubMed Central

    Hou, Qi; Wang, Dejuan; Huang, Wentao; Hu, Cheng; Li, Ke; Gao, Xin

    2015-01-01

    Objectives To evaluate the overall efficacy and safety of endoscopic enucleation of the prostate (EP) vs open prostatectomy (OP) for large benign prostatic hyperplasia (BPH). Methods We conducted an electronic search of PubMed/Medline, EMBASE, The Cochrane Library, and Web of Science to detect all relevant randomized controlled trials (RCTs) comparing EP with OP. A meta-analysis was performed using Review Manager 5.3. Results Seven RCTs (735 patients) were included. At the 3-, 6- and 12-month follow-up, there were no significant differences in the International Prostate Symptom Score (IPSS), maximum flow rate (Qmax), quality of life (QoL) score and post-void residual urine volume (PVR) between EP and OP. The International Index of Erectile Function (IIEF-5) was higher with EP (weighted mean difference [WMD]: 1.00, 95% confidence interval [CI]: 0.21 to 1.78, p=0.01) at the 12-month follow-up. The catheterization time (WMD: 3.80 d, 95%CI: -5.11 to -2.48, P<0.00001) and hospital stay (WMD: 4.93 d, 95%CI: -5.96 to -3.89, P<0.00001) were shorter with EP. The duration of operation was longer for EP compared with OP (WMD: 16.21 min, 95%CI: 3.72 to 28.70, P=0.01). The resected tissue weight (WMD: -9.63 g, 95%CI: -14.46 to -4.81, P<0.0001) and decrease in hemoglobin (WMD: -1.14 g/dL, 95%CI: -1.81 to -0.47, P=0.0008) were less with EP. EP was associated with fewer blood transfusions (risk ratio: 0.22, 95%CI: 0.10 to 0.47, P=0.0001). There were no significant differences between EP and OP when comparing other complications. Conclusions Although only a limited number of RCTs with relatively limited follow-up are available, EP is shown to have a similar postoperative profile and comparable safety to OP. By contrast, EP may have a more desirable perioperative profile. EP appears to be an effective and safe minimally invasive option for treating large prostates that requires only brief convalescence. PMID:25826453

  6. A rare case of non-insulinoma pancreatic hypoglycaemia syndrome (niphs) in an adult due to localised islet cell hyperplasia–successfully managed by enucleation

    PubMed Central

    Nayak, Hemanta K; Sothwal, Arpit; Raizaida, Nishant; Daga, Mradul kumar; Agarwal, Anil kumar; Durga, Garima

    2011-01-01

    Persistent hyperinsulinemic hypoglycaemia is caused most commonly by an insulinoma in adults or by nesidioblastosis in neonates. In adults, localised islet cell hyperplasia is a rare disorder characterised by localised proliferation of islet cells. The authors present the case of a previously healthy non-obese middle aged female with new-onset severe hypoglycaemia. Laboratory findings confirmed a case of hyperinsulinemic hypoglycaemia. Endoscopic ultrasonography, intra-arterial calcium stimulation test and intraoperative ultrasonography showed a lesion in the uncinate process that was enucleated. Rest of the pancreas was normal. Histological examination and immunostaining of the resected tissue revealed pancreatic tissue with maintained acinar pattern consistent with diagnosis of localised islet cell hyperplasia. The patient did not have further episodes of hypoglycaemia following the procedure. Localised islet cell hyperplasia with such a very high insulin level is exceedingly rare in adult populations and not reported in literature. This diagnosis cannot be easily made through routine diagnostic laboratory or radiological procedures and likely requires a histological diagnosis. Management of this rare entity is by enucleation. PMID:22675010

  7. Treatment of Hemorrhagic Vocal Polyps by Pulsed Dye Laser-Assisted Laryngomicrosurgery

    PubMed Central

    Byeon, Hyung Kwon; Han, Ji Hyuk; Choi, Byeong Il; Hwang, Hye Jin; Kim, Ji-Hoon; Choi, Hong-Shik

    2015-01-01

    Objective. Conventional surgical techniques of laryngomicrosurgery (LMS) on hemorrhagic vocal polyps are often difficult due to obscuration of the surgical field by inadvertent bleeding from the lesion, and there are often significant amounts of mucosal epithelium loss. Here, we introduce our surgical technique using pulsed dye laser (PDL), which can effectively resect the polyp with vocal fold mucosa preservation. Methods. Patients who were diagnosed with hemorrhagic vocal polyp and who were surgically managed using PDL from March 2013 to October 2014 were retrospectively reviewed. Preoperative and postoperative clinical outcomes and surgical findings were evaluated. Results. A total of 39 patients were treated with PDL-assisted enucleation LMS. The average age was 43.7 years (range 20–73), and there were 20 males and 19 females (17 professional voice users). In all cases, the hemorrhagic polyp was successfully enucleated after application of PDL, thereby preserving the overlying epithelium. Postoperative voice outcomes were favorable with clear preservation of the vocal fold mucosal wave. Conclusion. PDL-assisted enucleation LMS for the treatment of hemorrhagic vocal polyps can be a safe and effective surgical technique. It can be considered a promising treatment option for hemorrhagic vocal polyps. PMID:26557700

  8. Development of porcine embryos reconstituted with somatic cells and enucleated metaphase I and II oocytes matured in a protein-free medium

    PubMed Central

    Miyoshi, Kazuchika; Rzucidlo, S Jacek; Gibbons, John R; Arat, Sezen; Stice, Steven L

    2001-01-01

    Background Many cloned animals have been created by transfer of differentiated cells at G0/G1 or M phase of the cell cycle into enucleated M II oocytes having high maturation/meiosis/mitosis-promoting factor activity. Because maturation/meiosis/mitosis-promoting factor activity during oocyte maturation is maximal at both M I and M II, M I oocytes may reprogram differentiated cell nuclei as well. The present study was conducted to examine the developmental ability in vitro of porcine embryos reconstructed by transferring somatic cells (ear fibroblasts) into enucleated M I or M II oocytes. Results Analysis of the cell cycle stages revealed that 91.2 ± 0.2% of confluent cells were at the G0/G1 phase and 54.1 ± 4.4% of nocodazole-treated cells were at the G2/M phase, respectively. At 6 h after activation, nuclear swelling was observed in 50.0-88.9% and 34.4-39.5% of embryos reconstituted with confluent cells and nocodazole-treated cells regardless of the recipient oocytes, respectively. The incidence of both a swollen nucleus and polar body was low (6.3-10.5%) for all nocodazole-treated donor cell regardless of the recipient oocyte. When embryos reconstituted with confluent cells and M I oocytes were cultured, 2 (1.5%) blastocysts were obtained and this was significantly (P < 0.05) lower than that (7.6%) of embryos produced by transferring confluent cells into M II oocytes. No reconstructed embryos developed to the blastocyst stage when nocodazole-treated cells were used as donors. Conclusions Porcine M I oocytes have a potential to develop into blastocysts after nuclear transfer of somatic cells. PMID:11476669

  9. Safety of cornea and iris in ocular surgery with 355-nm lasers

    NASA Astrophysics Data System (ADS)

    Wang, Jenny; Chung, Jae Lim; Schuele, Georg; Vankov, Alexander; Dalal, Roopa; Wiltberger, Michael; Palanker, Daniel

    2015-09-01

    A recent study showed that 355-nm nanosecond lasers cut cornea with similar precision to infrared femtosecond lasers. However, use of ultraviolet wavelength requires precise assessment of ocular safety to determine the range of possible ophthalmic applications. In this study, the 355-nm nanosecond laser was evaluated for corneal and iris damage in rabbit, porcine, and human donor eyes as determined by minimum visible lesion (MVL) observation, live/dead staining of the endothelium, and apoptosis assay. Single-pulse damage to the iris was evaluated on porcine eyes using live/dead staining. In live rabbits, the cumulative median effective dose (ED50) for corneal damage was 231 J/cm2, as seen by lesion observation. Appearance of endothelial damage in live/dead staining or apoptosis occurred at higher radiant exposure of 287 J/cm2. On enucleated rabbit and porcine corneas, ED50 was 87 and 52 J/cm2, respectively, by MVL, and 241 and 160 J/cm2 for endothelial damage. In human eyes, ED50 for MVL was 110 J/cm2 and endothelial damage at 453 J/cm2. Single-pulse iris damage occurred at ED50 of 208 mJ/cm2. These values determine the energy permitted for surgical patterns and can guide development of ophthalmic laser systems. Lower damage threshold in corneas of enucleated eyes versus live rabbits is noted for future safety evaluation.

  10. The free electron laser: a system capable of determining the gold standard in laser vision correction

    NASA Astrophysics Data System (ADS)

    Fowler, W. Craig; Rose, John G.; Chang, Daniel H.; Proia, Alan D.

    1999-06-01

    Introduction. In laser vision correction surgery, lasers are generally utilized based on their beam-tissue interactions and corneal absorption characteristics. Therefore, the free electron laser, with its ability to provide broad wavelength tunability, is a unique research tool for investigating wavelengths of possible corneal ablation. Methods. Mark III free electron laser wavelengths between 2.94 and 6.7 μm were delivered in serial 0.1 μm intervals to corneas of freshly enucleated porcine globes. Collateral damage, ablation depth, and ablation diameter were measured in histologic sections. Results. The least collateral damage (12-13 μm) was demonstrated at three wavelengths: 6.0, 6.1 (amide I), and 6.3 μm. Minimal collateral damage (15 μm) was noted at 2.94 μm (OH-stretch) and at 6.2 μm. Slightly greater collateral damage was noted at 6.45 μm (amide II), as well as at the 5.5-5.7 μm range, but this was still substantially less than the collateral damage noted at the other wavelengths tested. Conclusions. Our results suggest that select mid-infrared wavelengths have potential for keratorefractive surgery and warrant additional study. Further, the free electron laser's ability to allow parameter adjustment in the far-ultraviolet spectrum may provide unprecedented insights toward establishing the gold-standard parameters for laser vision correction surgery.

  11. A Review of Laser Treatment for Symptomatic BPH (Benign Prostatic Hyperplasia).

    PubMed

    Nair, Shiva Madhwan; Pimentel, Marie Adrianne; Gilling, Peter John

    2016-06-01

    Benign prostatic hyperplasia (BPH) is the predominant cause of bladder outflow obstruction and is associated with significant morbidity. Surgical removal of adenoma has been a key treatment principle for alleviation of obstruction. Lasers have been used as an alternative to transurethral resection of the prostate (TURP), due to the higher complications of the latter procedure, since the early 1990s. Early generations of lasers utilized coagulative and ablative techniques to dis-obstruct the bladder. Ablative techniques have remained popular with the resurgence of 532-nm vaporization (commonly known as GreenLight). Enucleation techniques especially with the holmium laser have shown durable efficacy in randomized controlled trials whilst new modalities such as thulium still require long-term data. This review examines the most common types of laser technology used in BPH surgery, with a focus on efficacy and side effect profile. PMID:27053186

  12. Five years follow-up of a keratocyst odontogenic tumor treated by marsupialization and enucleation: A case report and literature review

    PubMed Central

    de Molon, Rafael Scaf; Verzola, Mario H.; Pires, Luana C.; Mascarenhas, Vinicius I.; da Silva, Rodrigo B.; Cirelli, Joni A.; Barbeiro, Roberto H.

    2015-01-01

    Odontogenic cysts are considered as nonneoplasic benign lesions. Among the cysts, keratocyst odontogenic tumor (KCOT) is an intra-osseous tumor characterized by parakeratinized stratified squamous epithelium and a potential for aggressive, infiltrative behavior, and for the possibility to develop carcinomas in the lesion wall. Thus, the aim of this study was to describe a clinical case of KCOT in a young patient and discuss the treatment alternatives to solve this case. A 15-year-old male was referred for treatment of a giant lesion in his left side of the mandible. After the biopsy, a diagnostic of KCOT was made, and the following procedures were planned for KCOT treatment. Marsupialization was performed for lesion decompression and consequent lesion size reduction. Afterward, enucleation for complete KCOT removal was performed followed by third mandibular molar extraction. After 5 years, no signs of recurrence were observed. The treatment proposed was efficient in removing the KCOT with minimal surgical morbidity and optimal healing process, and the first and second mandibular molars were preserved with pulp vitality. In conclusion, this treatment protocol was an effective and conservative approach for the management of the KCOT, enabling the reduction of the initial lesion, the preservation of anatomical structures and teeth, allowing quicker return to function. No signs of recurrence after 5 years were observed. PMID:25821360

  13. [A Case of Holmium: YAG Laser Resection of Superficial Bladder Tumor (HoLRBT)].

    PubMed

    Sugita, Yoshiko; Shitara, Toshiya; Hirayama, Takahiro; Fujita, Tetsuo; Yoshida, Kazunari; Kubo, Seiichi; Iwamura, Masatsugu

    2015-10-01

    We present a case of holmium : YAG laser resection of superficial bladder tumor (HoLRBT). A 73-year-old male was referred to our hospital with elevated prostatic specific antigen. Due to difficulty of urination, holmium : YAG laser enucleation of the prostate was performed under the diagnosis of benign prostatic hyperplasia. During the surgery, superficial bladder tumor was incidentally identified, and HoLRBT was performed. After the operation, histopathological examination revealed urothelial carcinoma, G2 > G1, pTa. The patient has been subsequently followed up for 9 months, and there areno evidence of recurrence. Changing the holmium : YAG laser energy setting can potentially be effective and safe to approach a superficial bladder tumor. PMID:26563623

  14. Investigations for the correction of presbyopia by fs-laser-induced cuts

    NASA Astrophysics Data System (ADS)

    Ripken, Tammo; Oberheide, Uwe; Heisterkamp, Alexander; Ertmer, Wolfgang; Gerten, Georg; Lubatschowski, Holger

    2004-07-01

    The most probable reason for presbyopia is an age-related loss of the elasticity of the lens. It develops through the whole life, but is first noticeable typically at the age of about 45. From that on it leads within 15 years to a total loss of the accommodation ability. However, both, the ciliary muscle and the lens capsule stay active and elastic, respectively. With respect to this, a possible treatment conception is to increase or regain the elasticity. The possibility to increase elasticity with ps-laser induced cuts inside the lens was already shown by Krueger. We made an improvement in cutting quality while using a fs laser with 5~kHz repetition rate emitting in the near infrared. Different fs-laser-induced μm smooth cuts inside fresh enucleated ex-vivo pig lenses will be presented.

  15. Chemically Assisted Enucleation Results in Higher G6PD Expression in Early Bovine Female Embryos Obtained by Somatic Cell Nuclear Transfer

    PubMed Central

    Oliveira, Clara Slade; Tetzner, Tatiane Almeida Drummond; de Lima, Marina Ragagnin; de Melo, Danilas Salinet; Niciura, Simone Cristina Méo; Garcia, Joaquim Mansano

    2012-01-01

    Abstract Despite extensive efforts, low efficiency is still an issue in bovine somatic cell nuclear transfer (SCNT). The hypothesis of our study was that the use of cytoplasts produced by chemically assisted enucleation (EN) would improve nuclear reprogramming in nuclear transfer (NT)–derived embryos because it results in lower damage and higher cytoplasm content than conventional EN. For that purpose, we investigated the expression of two X-linked genes: X inactive-specific transcript (XIST) and glucose 6-phosphate dehydrogenase (G6PD). In the first experiment, gene expression was assessed in day-7 female blastocysts from embryonic cell NT (ECNT) groups [conventional, ECNT conv; chemically assisted, ECNT deme (demecolcine)]. Whereas in the ECNT conv group, only one embryo (25%; n=4) expressed XIST transcripts, most embryos showed XIST expression (75%; n=4) in the ECNT deme group. However, no significant differences in transcript abundance of XIST and G6PD were found when comparing the embryos from all groups. In a second experiment using somatic cells as nuclear donors, we evaluated gene expression profiles in female SCNT-derived embryos. No significant differences in relative abundance (RA) of XIST transcripts were observed among the groups. Nonetheless, higher (p<0.05) levels of G6PD were observed in SCNT deme and in vitro–derived groups in comparison to SCNT conv. To know whether higher G6PD expression in embryos derived from SCNT chemically assisted EN indicates higher metabolism in embryos considered of superior quality or if the presence of higher reactive oxygen species (ROS) levels generated by the increased oxygen consumption triggers G6PD activation, the expression of genes related to stress response should be investigated in embryos produced by that technique. PMID:22908977

  16. Current Laser Treatments for Benign Prostatic Hyperplasia

    PubMed Central

    Son, Hwancheol; Song, Sang Hoon

    2010-01-01

    The latest technical improvements in the surgical armamentarium are remarkable. In particular, advancements in the urologic field are so exceptional that we could observe the flare-up of robot-assisted laparoscopic radical prostatectomy for prostate cancer and laser prostatectomy for benign prostatic hyperplasia (BPH). Photoselective vaporization of the prostate (PVP) and holmium laser prostatectomy are the most generalized options for laser surgery of BPH, and both modalities have shown good postoperative results. In comparison to transurethral prostatectomy (TURP), they showed similar efficacy and a much lower complication rate in randomized prospective clinical trials. Even in cases of large prostates, laser prostatectomy showed comparable efficacy and safety profiles compared to open prostatectomy. From a technical point of view, PVP is considered to be an easier technique for the urologist to master. Furthermore, patients can be safely followed up in an outpatient clinic. Holmium laser enucleation of the prostate (HoLEP) mimics open prostatectomy because the adenomatous tissue is peeled off the surgical capsule in both procedures. Therefore, HoLEP shows notable volume reduction of the prostate similar to open prostatectomy with fewer blood transfusions, shorter hospital stay, and cost reduction regardless of prostate size. Outcomes of laser prostatectomy for BPH are encouraging but sometimes are unbalanced because safety and feasibility studies were reported mainly for PVP, whereas long-term data are mostly available for HoLEP. We need longer-term randomized clinical data to identify the reoperation rate of PVP and to determine which procedure is the ideal alternative to TURP and open prostatectomy for each patient. PMID:21165192

  17. Focusing of laser beams by the eye's optics

    NASA Astrophysics Data System (ADS)

    Zheltov, Georgi I.; Rubanov, Alexander S.

    1998-10-01

    The radial distribution of Gaussian beams radiation intensity on the focal plain of the ocular optical system has been calculated using the human eye Modulation Transfer Function. The dependencies of the distribution on the distance to the beam's constriction have been analyzed for the visible spectral range at a given eye accommodation. More consideration has been given to the conditions of the most `sharp' focusing of laser beams onto the retina (the most dangerous cases) and to the typical errors arising in the process retinal irradiance distribution measurement through the pupil. The analogous model has been created for the eyes of some animals. The results of calculations are in a good agreement with direct measurements data at the back pole of enucleated rabbit eyes.

  18. Laser Technology.

    ERIC Educational Resources Information Center

    Gauger, Robert

    1993-01-01

    Describes lasers and indicates that learning about laser technology and creating laser technology activities are among the teacher enhancement processes needed to strengthen technology education. (JOW)

  19. Comparison of in situ Corneoscleral Disc Excision versus Whole Globe Enucleation in Cornea Donors Regarding Microbial Contamination in Organ Culture Medium – a Prospective Monocentric Study over 9 Years

    PubMed Central

    Schroeter, Jan; Wilkemeyer, Ina; Herrlinger, Frithjof; Pruss, Axel

    2012-01-01

    Summary Background Corneas needed for keratoplasty can be harvested using two techniques: whole globe enucleation and in situ excision of the corneoscleral disc. This study evaluates the rate of microbial contamination of the donor cornea organ culture medium according to the method of retrieval. Methods All donor corneas of our cornea bank received between January 1, 2001 and December 31, 2009 put into organ culture and microbio-logically tested were prospectively analyzed for microbial contamination of the organ culture medium. Results 2,805 donor corneas could be included in this study in total. 975 of them were retrieved by whole globe enucleation (group 1) and 1,830 by in situ corneoscleral disc excision (group 2). 15 corneas of group 1 (1.5%) and 46 corneas of group 2 (2.5%) showed a contamination of the organ culture medium. The difference was shown not to be statistically significant (p = 0.082). Conclusion The rate of microbial contamination in organ-cultured donor corneas does not seem to be dependent on the method of their retrieval. PMID:23801381

  20. Improved efficiency of microsurgical enucleated tripronuclear zygotes development and embryonic stem cell derivation by supplementing epidermal growth factor, brain-derived neurotrophic factor, and insulin-like growth factor-1.

    PubMed

    Fan, Yong; Li, Rong; Huang, Jin; Zhao, Hong-Cui; Ding, Ting; Sun, Xiaofang; Yu, Yang; Qiao, Jie

    2014-03-15

    Human embryonic stem cells (hESCs) hold great promise for future clinical cell therapies because of their unique potential to differentiate into all human cell types. However, the destruction of normal fertilized embryos and the derivation of hESCs for research has resulted in polarized ethical debates, with most of the controversy centered on embryo destruction. Therefore, due to less ethical controversy surrounding them, abnormal fertilized zygotes that are usually discarded are a potential feasible resource for the derivation of hESCs. Microsurgery on human polyspermic zygotes can contribute to the derivation of hESCs, but the efficiency is much lower. Here, we reported a culture system to enhance the developmental competence of such microsurgical human polyspermic zygotes by EGF-BDNF-IGF-1 combination, which eventually resulted in the increased derivation efficiency of hESCs from them. We found that the developmental efficiency of microsurgical enucleated tripronuclear (3PN) embryos cultured with the EGF-BDNF-IGF-1 combination was significantly increased compared with the control group. More importantly, when the microsurgical enucleated 3PN embryos were cultured in medium supplemented with EGF-BDNF-IGF-1, the frequency ratio of chromosome abnormality was reduced. Our present study will facilitate the development of hESC line derivation in subsequent studies and also provide an additional choice for infertile couples. PMID:24261581

  1. Laparoscopic enucleation of pancreatic insulinomas.

    PubMed

    Schraibman, Vladimir; Goldenberg, Alberto; de Matos Farah, Jose Francisco; Apodaca, Franz Robert; Goldman, Suzan; Lobo, Edson Jose

    2007-08-01

    Insulinomas are rare endocrine pancreatic tumors whose incidence has been increasing in recent years owing to early detection by clinical and radiologic, such as remote neural monitoring, computed tomography (CT), and ultrasound (US) findings. The classical treatment consists of open surgical resection, which is associated with relative morbidity and mortality rates. The aim of this paper was to present 5 patients who were diagnosed with pancreatic insulinomas that were treated by laparoscopic resection. Five (5) patients, ranging from 14 to 45 years and presenting with classical Whipple Triad, had lesions ranging from 1.5 to 2.5 cm by CT (body and tail of the pancreas), which were subsequently diagnosed as insulinomas. An ecoendoscopy showed no combined lesions. They were treated by a laparoscopic resection. Glicemic levels were controlled during surgery with an expected glucose rise. All patients had an uneventfull recovery. The mean length of follow-up is 14 months. The laparoscopic resection of pancreatic insulinomas is a reliable procedure for superficial lesions in the body and tail of the pancreas. PMID:17705715

  2. Understanding lasers

    SciTech Connect

    Gibilisco, S.

    1989-01-01

    Covering all different types of laser applications-Gibilisco offers an overview of this fascinating phenomenon of light. Here he describes what lasers are and how they work and examines in detail the different kinds of lasers in use today. Topics of particular interest include: the way lasers work; the different kinds of lasers; infrared, ultraviolet and x-ray lasers; use of lasers in industry and manufacturing; use of lasers for long-distance communications; fiberoptic communications; the way laser shows work; the reality of Star Wars; lasers in surgical and medical applications; and holography and the future of laser technology.

  3. High-Resolution In Vivo Imaging of Regimes of Laser Damage to the Primate Retina

    PubMed Central

    Pocock, Ginger M.; Oliver, Jeffrey W.; Specht, Charles S.; Estep, J. Scot; Noojin, Gary D.; Schuster, Kurt; Rockwell, Benjamin A.

    2014-01-01

    Purpose. To investigate fundamental mechanisms of regimes of laser induced damage to the retina and the morphological changes associated with the damage response. Methods. Varying grades of photothermal, photochemical, and photomechanical retinal laser damage were produced in eyes of eight cynomolgus monkeys. An adaptive optics confocal scanning laser ophthalmoscope and spectral domain optical coherence tomographer were combined to simultaneously collect complementary in vivo images of retinal laser damage during and following exposure. Baseline color fundus photography was performed to complement high-resolution imaging. Monkeys were perfused with 10% buffered formalin and eyes were enucleated for histological analysis. Results. Laser energies for visible retinal damage in this study were consistent with previously reported damage thresholds. Lesions were identified in OCT images that were not visible in direct ophthalmoscopic examination or fundus photos. Unique diagnostic characteristics, specific to each damage regime, were identified and associated with shape and localization of lesions to specific retinal layers. Previously undocumented retinal healing response to blue continuous wave laser exposure was recorded through a novel experimental methodology. Conclusion. This study revealed increased sensitivity of lesion detection and improved specificity to the laser of origin utilizing high-resolution imaging when compared to traditional ophthalmic imaging techniques in the retina. PMID:24891943

  4. Corneal photoablation in vivo with the erbium:YAG laser: first report

    NASA Astrophysics Data System (ADS)

    Jean, Benedikt J.; Bende, Thomas; Matallana, Michael; Kriegerowski, Martin

    1995-05-01

    As an alternative to far-UV lasers for corneal refractive surgery, the Erbium:YAG laser may be used in TEM00 mode. The resulting gaussian beam profile leads to a certain amount of myopic correction per laser pulse. Although animal data suggest that the clinical outcome should be comparable to the UV-lasers, no human data were available until now. We performed Erbium:YAG laser areal ablation in 5 blind human eyes. In TEM00 mode, the laser parameters were: effective diameter of laser spot equals 3.4 mm, fluence equals 380 mJ/cm2, pulse duration equals 250 microsecond(s) , Repetition rate equals 4 Hz, Number of applied laser pulses equals 15. Four patients with no light perception, one with intact light projection on one eye (some of them scheduled for enucleation) were treated under topical anaesthesia. Patient selection and informed consent were agreed to by the University's independent Ethics Committee. Prior to laser irradiation, corneal epithelium was removed. A postoperative silicone cast of the cornea was analyzed with a confocal laser micro-topometer for the ablation profile. The eyes were treated with antibiotic ointment until the epithelium was closed. Clinical appearance and, where possible, profilometry of the ablated area was observed. The ablation profile in cornea was gaussian shaped with a maximal depth of 30 micrometers . During laser treatment, the corneal surface becomes opaque, clearing in a matter of seconds. Epithelial healing and clinical appearance was similar to excimer laser treatment. However, during the first week, the irradiated area shows subepithelial irregularities, resembling small bubbles, disappearing thereafter.

  5. Sutureless cataract incision closure using laser-activated tissue glues

    NASA Astrophysics Data System (ADS)

    Eaton, Alexander M.; Bass, Lawrence S.; Libutti, Steven K.; Schubert, Herman D.; Treat, Michael R.

    1991-06-01

    With the advent of phacoemulsification and foldable intraocular lenses, there is renewed interest in sutureless cataract wound. We report the use of laser activated tissue glues for the closure of scleral tunnel cataract incisions. Two glue mixtures were tested in enucleated porcine eyes. Glue A was composed of hyaluronic acid, human albumin, and indocyanine green dye. Glue B contained hyaluronic acid, chondroitin sulfate, human albumin, and indocyanine green dye. A Spectra Physics diode laser (808 nm) with a power density of 7-1 1 watts/cm2 was used for glue activation. Wound bursting pressures, as determined by the presence of fluid at the wound margin, was significantly higher with both glue combinations than without the glue (Plaser activated tissue glues may be an alternative to suture closure of scleral tunnel cataract incisions.

  6. Laser speckle tracking for monitoring and analysis of retinal photocoagulation

    NASA Astrophysics Data System (ADS)

    Seifert, Eric; Bliedtner, Katharina; Brinkmann, Ralf

    2014-02-01

    Laser coagulation of the retina is an established treatment for several retinal diseases. The absorbed laser energy and thus the induced thermal damage varies with the transmittance and scattering properties of the anterior eye media and with the pigmentation of the fundus. The temperature plays the most important role in the coagulation process. An established approach to measure a mean retinal temperature rise is optoacoustics, however it provides limited information on the coagulation. Phase sensitive OCT potentially offers a three dimensional temporally resolved temperature distribution but is very sensitive to slightest movements which are clinically hard to avoid. We develop an optical technique able to monitor and quantify thermally and coagulation induced tissue movements (expansions and contractions) and changes in the tissue structure by dynamic laser speckle analysis (LSA) offering a 2D map of the affected area. A frequency doubled Nd:YAG laser (532nm) is used for photocoagulation. Enucleated porcine eyes are used as targets. The spot is 100μm. A Helium Neon laser (HeNe) is used for illumination. The backscattered light of a HeNe is captured with a camera and the speckle pattern is analyzed. A Q-switched Nd:YLF laser is used for simultaneous temperature measurements with the optoacoustic approach. Radial tissue movements in the micrometer regime have been observed. The signals evaluation by optical flow algorithms and generalized differences tuned out to be able to distinguish between regions with and without immediate cell damage. Both approaches have shown a sensitivity of 93% and a specificity above 99% at their optimal threshold.

  7. Evaluation of holmium laser for transurethral deroofing of severe and multiloculated prostatic abscesses

    PubMed Central

    Lee, Chan Ho; Ku, Ja Yoon; Park, Young Joo; Lee, Jeong Zoo

    2015-01-01

    Purpose Our objective was to evaluate the use of a holmium laser for transurethral deroofing of a prostatic abscess in patients with severe and multiloculated prostatic abscesses. Materials and Methods From January 2011 to April 2014, eight patients who were diagnosed with prostatic abscesses and who underwent transurethral holmium laser deroofing at Pusan National University Hospital were retrospectively reviewed. Results Multiloculated or multifocal abscess cavities were found on the preoperative computed tomography (CT) scan in all eight patients. All patients who underwent transurethral holmium laser deroofing of a prostatic abscess had successful outcomes, without the need for secondary surgery. Of the eight patients, seven underwent holmium laser enucleation of the prostate (HoLEP) for the removal of residual adenoma. Markedly reduced multiloculated abscess cavities were found in the follow-up CT in all patients. No prostatic abscess recurrence was found. Transient stress urinary incontinence was observed in three patients. The stress urinary incontinence subsided within 3 weeks in two patients and improved with conservative management within 2 months in the remaining patient. Conclusions Transurethral holmium laser deroofing of prostatic abscesses ensures successful drainage of the entire abscess cavity. Because we resolved the predisposing conditions of prostatic abscess, such as bladder outlet obstruction and prostatic calcification, by simultaneously conducting HoLEP, there was no recurrence of the prostatic abscesses after surgery. We recommend our method in patients requiring transurethral drainage. PMID:25685303

  8. Laser ignition

    DOEpatents

    Early, James W.; Lester, Charles S.

    2002-01-01

    In the apparatus of the invention, a first excitation laser or other excitation light source is used in tandem with an ignitor laser to provide a compact, durable, engine deployable fuel ignition laser system. The beam from the excitation light source is split with a portion of it going to the ignitor laser and a second portion of it being recombined with the first portion after a delay before injection into the ignitor laser. Reliable fuel ignition is provided over a wide range of fuel conditions by using a single remote excitation light source for one or more small lasers located proximate to one or more fuel combustion zones.

  9. Lasers of All Sizes

    NASA Astrophysics Data System (ADS)

    Balcou, Philippe; Forget, Sébastien Robert-Philip, Isabelle

    2015-10-01

    * Introduction * The Laser in All Its Forms * Gas lasers * Dye lasers * Solid-state lasers * Lasers for Every Taste * The rise of lasers * Lasers of all sizes * The colors of the rainbow... and beyond * Shorter and shorter lasers * Increasingly powerful lasers * Lasers: A Universal Tool? * Cutting, welding, and cleaning * Communicating * Treating illnesses * Measuring * Supplying energy? * Entertaining * Understanding * Conclusion

  10. Laser therapy

    MedlinePlus

    ... be used for many medical purposes. Because the laser beam is so small and precise, it allows health care providers to safely treat tissue without injuring the surrounding area. Lasers are often used to: Treat varicose veins Improve ...

  11. Laser microphone

    DOEpatents

    Veligdan, James T.

    2000-11-14

    A microphone for detecting sound pressure waves includes a laser resonator having a laser gain material aligned coaxially between a pair of first and second mirrors for producing a laser beam. A reference cell is disposed between the laser material and one of the mirrors for transmitting a reference portion of the laser beam between the mirrors. A sensing cell is disposed between the laser material and one of the mirrors, and is laterally displaced from the reference cell for transmitting a signal portion of the laser beam, with the sensing cell being open for receiving the sound waves. A photodetector is disposed in optical communication with the first mirror for receiving the laser beam, and produces an acoustic signal therefrom for the sound waves.

  12. Fs-laser induced elasticity changes to improve presbyopic lens accommodation

    NASA Astrophysics Data System (ADS)

    Ripken, T.; Oberheide, U.; Ziltz, C.; Ertmer, W.; Gerten, G.; Lubatschowski, H.

    2005-04-01

    According to Helmholtz' theory of accommodation one of the mayor reasons for the development of presbyopia is the increasing sclerosis of the lens. One concept to delay the process of sclerosis or even regain the deformation ability of the lens might be the treatment of the lens by femtosecond laser pulses. Our aim was to evaluate appropriate laser parameters for this possible treatment and to analyse potential changes in deformation ability of the treated lenses. We performed different cutting patterns in enucleated pig lenses (ex vivo) using the disruptive effect of an ultrafast near-infrared laser induced optical breakdown. Pulse energies and spot separation of the laser pulses were varied to investigate the effect on the generated cut. For an evaluation of the gain in deformation ability the lenses were rotated before and after treatment and the changes in lens thickness due to centrifugal forces were measured. In result, a smooth cutting was possible with appropriate parameters. The experiments showed an increase of elasticity in 70% of the eyes. When the lenses were treated more statistically, an average deformation ability increase of nearly 20%, determined by the change of thickness between untreated and treated lens, was measured.

  13. Preliminary study on the closure of the lens capsule by laser welding

    NASA Astrophysics Data System (ADS)

    Pini, Roberto; Rossi, Francesca; Menabuoni, Luca; Lenzetti, Ivo; Rossi, Giacomo; Parel, Jean-Marie

    2006-02-01

    We present a preliminary study of a new method, based on the laser welding of suitably prepared patches of capsular tissue for the closure of capsulorhexes in the lens capsule. This technique is proposed for the repair capsular breaks or tears caused by accidental traumas or ones produced intraoperatively during standard IOL implantation. Experiments were carried out ex vivo on freshly enucleated porcine eyes. Patches of anterior capsular tissue, collected from donor eyes, were stained with a solution of Indocyanine Green (ICG) in sterile water. Closure tests on a capsulorhexis were performed by welding a stained patch onto the recipient capsule, using diode laser radiation at 810 nm, which greatly absorbed by the ICG-stained tissue. Laser radiation was delivered by means of a 200-micron-core-fiber, the tip of which was gently pressed onto the patch surface (contact welding technique) so as to produce effective tissue welding in underwater conditions. Laser-welded capsular tissue was found to have good resistance to mechanical load, comparable in fact to that of healthy tissue.

  14. Morphologic evaluations of Q-switched Nd:YAG laser injury of human retina

    NASA Astrophysics Data System (ADS)

    Scales, David K.; Schuschereba, Steven T.; Lund, David J.; Stuck, Bruce E.

    1997-05-01

    Depiction of the cellular and immune responses in the human model is critical to design rational therapies preventing/limiting cellular destruction and ultimately functional visual loss following acute laser injuries. We report the light and electron microscopy histologic findings in a controlled ocular human laser exposure. Following informed consent, the normal eye of a patient scheduled to undergo exenteration for invasive carcinoma of the orbit was exposed to both continuous wave and Q-switched lasers. Four hours prior to exenteration, argon G lesions were placed in the superior/temporal quadrant and Nd:YAG lesions were placed in the inferior/temporal quadrant. After enucleation, the retina was prepared for routine light and transmission electron microscopy. Histology of the argon G lesions showed primarily photoreceptor and RPE photocoagulation damage. Neutrophil adhesion was limited within the choroid and no neutrophils were observed in the subretinal space. In contrast, the 4 hr Nd:YAG lesions showed extensive retinal disruption, hemorrhage within subretinal and intraretinal spaces, neutrophil accumulation in the retina, and an extensive neutrophil chemotaxic and emigration response in the choroid. Severe laser injuries elicit a significant neutrophil response by 4 hr, suggesting that neutrophils should be an early stage therapeutic target.

  15. Management of large prostatic adenoma: Lasers versus bipolar transurethral resection of prostate.

    PubMed

    Gupta, Narmada P; Nayyar, Rishi

    2013-07-01

    Transurethral resection of prostate (TURP) has long been the most commonly performed surgical procedure for the management of benign prostate enlargement (BPE), but has several associated limitations. Over the years, laser techniques have developed as major contenders as alternative therapies for BPE. However, simultaneously, TURP has also flourished and with relatively recent development of resection in saline (bipolar TURP), the tussle between laser techniques and TURP has further gained momentum. A systematic search was performed on Medline using the various Medical subject headings related to the surgical management of BPE including TURP, bipolar, lasers, holmium laser enucleation of prostate (HoLEP), photo-selective vaporization of prostate (PVP), etc., All articles types including meta-analysis randomized controlled trials, review articles, guidelines from various urological associations, single center studies from 2002 onward were considered for review. Bipolar TURP, HoLEP, and PVP provide equivalent outcomes for large prostate adenoma (<60 g). For extremely large glands (<150 g), HoLEP is a very efficacious endoscopic alternative to open prostatectomy and has proven long-term results over more than a decade. Bipolar TURP and PVP are attractive with a minimal learning curves and equivalent short term durability. Surgical management of large prostate should be individualized based upon patient's comorbidities and surgeon's expertise. PMID:24082445

  16. Management of large prostatic adenoma: Lasers versus bipolar transurethral resection of prostate

    PubMed Central

    Gupta, Narmada P; Nayyar, Rishi

    2013-01-01

    Transurethral resection of prostate (TURP) has long been the most commonly performed surgical procedure for the management of benign prostate enlargement (BPE), but has several associated limitations. Over the years, laser techniques have developed as major contenders as alternative therapies for BPE. However, simultaneously, TURP has also flourished and with relatively recent development of resection in saline (bipolar TURP), the tussle between laser techniques and TURP has further gained momentum. A systematic search was performed on Medline using the various Medical subject headings related to the surgical management of BPE including TURP, bipolar, lasers, holmium laser enucleation of prostate (HoLEP), photo-selective vaporization of prostate (PVP), etc., All articles types including meta-analysis randomized controlled trials, review articles, guidelines from various urological associations, single center studies from 2002 onward were considered for review. Bipolar TURP, HoLEP, and PVP provide equivalent outcomes for large prostate adenoma (<60 g). For extremely large glands (<150 g), HoLEP is a very efficacious endoscopic alternative to open prostatectomy and has proven long-term results over more than a decade. Bipolar TURP and PVP are attractive with a minimal learning curves and equivalent short term durability. Surgical management of large prostate should be individualized based upon patient's comorbidities and surgeon's expertise. PMID:24082445

  17. Laser welding of chitosan-GNRs films for the closure of a capsulorhexis

    NASA Astrophysics Data System (ADS)

    Rossi, Francesca; Matteini, Paolo; Ratto, Fulvio; Menabuoni, Luca; Lenzetti, Ivo; Pini, Roberto

    2011-03-01

    In this work we present the first attempt to close the anterior lens capsule bag by the use of chitosan patches, where Gold Nanorods (GNRs) are embedded. GNRs exhibit intense localized plasmon resonances at optical frequencies in the near infrared (NIR): upon excitation with a NIR laser, a strong photothermal effect is produced, which can be exploited to develop minimally invasive therapies. Here we use the chitosan-GNRs films as a novel NIR sensitive nanocomposite for the photothermal conversion of NIR laser light during surgical interventions of tissue welding. Chitosan is an attractive biomaterial due to its biodegradability, biocompatibility, antimicrobial and wound healing-promoting activity. Colloidal GNRs were embedded in chitosan based, highly stabilized, flexible and easy-to-handle films, which were stored in water until the time of surgery. In these preliminary tests, a capsulorhexis was performed in freshly enucleated porcine eyes. The lens was aspired, then the patch was put onto the capsule bag and welded: a diode laser (810 nm) was used to deliver single spots (200 μm core diameter optical fiber) of local capsule/patch adhesion. Then the bag was refilled with silicon oil. The result is an immediate closure of the capsular tissue, with high mechanical strength. The laser welded chitosan- GNRs films are an innovative and highly stable solution to be exploited for the treatment of capsular breaks and for the implementation of a lens refilling procedure.

  18. Nonablative lasers.

    PubMed

    Nouri, Keyvan; Rivas, Maria Patricia; Bouzari, Navid; Faghih, Sahar

    2006-06-01

    The trend toward minimally invasive rejuvenation techniques has led to the widespread use of nonablative lasers. Nonablative lasers can be classified in two groups based on their wavelengths: lasers emitting light in the visible range, and those emitting in the infrared range. In this review, different laser and intense pulsed light (IPL) systems are presented and critically discussed along with findings of the studies in the literature. PMID:17173583

  19. Laser driver

    SciTech Connect

    Culpepper, C.F.

    1989-03-14

    A laser driver for a laser diode is described, consisting of: an impedance matched input buffer amplifier to which a modulation signal is applied; and a current source coupled to the output of the impedance matched input buffer amplifier, the output of the current source providing an essentially constant amplitude a.c. current component coupled to drive the laser diode.

  20. Laser ignition

    DOEpatents

    Early, James W.; Lester, Charles S.

    2004-01-13

    Sequenced pulses of light from an excitation laser with at least two resonator cavities with separate output couplers are directed through a light modulator and a first polarzing analyzer. A portion of the light not rejected by the first polarizing analyzer is transported through a first optical fiber into a first ignitor laser rod in an ignitor laser. Another portion of the light is rejected by the first polarizing analyzer and directed through a halfwave plate into a second polarization analyzer. A first portion of the output of the second polarization analyzer passes through the second polarization analyzer to a second, oscillator, laser rod in the ignitor laser. A second portion of the output of the second polarization analyzer is redirected by the second polarization analyzer to a second optical fiber which delays the beam before the beam is combined with output of the first ignitor laser rod. Output of the second laser rod in the ignitor laser is directed into the first ignitor laser rod which was energized by light passing through the first polarizing analyzer. Combined output of the first ignitor laser rod and output of the second optical fiber is focused into a combustible fuel where the first short duration, high peak power pulse from the ignitor laser ignites the fuel and the second long duration, low peak power pulse directly from the excitation laser sustains the combustion.

  1. CW laser pumped emerald laser

    SciTech Connect

    Shand, M.L.; Lai, S.T.

    1984-02-01

    A CW laser-pumped emerald laser is reported. A 34 percent output power slope efficiency is observed with longitudinal pumping by a krypton laser in a nearly concentric cavity. The laser has been tuned from 728.8 to 809.0 nm. Losses in emerald are larger than those of alexandrite determined in a similar cavity. The present data also indicate that the excited state absorption minimum is shifted from that of alexandrite. 13 references.

  2. Laser device

    DOEpatents

    Scott, Jill R.; Tremblay, Paul L.

    2004-11-23

    A laser device includes a target position, an optical component separated a distance J from the target position, and a laser energy source separated a distance H from the optical component, distance H being greater than distance J. A laser source manipulation mechanism exhibits a mechanical resolution of positioning the laser source. The mechanical resolution is less than a spatial resolution of laser energy at the target position as directed through the optical component. A vertical and a lateral index that intersect at an origin can be defined for the optical component. The manipulation mechanism can auto align laser aim through the origin during laser source motion. The laser source manipulation mechanism can include a mechanical index. The mechanical index can include a pivot point for laser source lateral motion and a reference point for laser source vertical motion. The target position can be located within an adverse environment including at least one of a high magnetic field, a vacuum system, a high pressure system, and a hazardous zone. The laser source and an electro-mechanical part of the manipulation mechanism can be located outside the adverse environment. The manipulation mechanism can include a Peaucellier linkage.

  3. Laser device

    DOEpatents

    Scott, Jill R.; Tremblay, Paul L.

    2007-07-10

    A laser device includes a target position, an optical component separated a distance J from the target position, and a laser energy source separated a distance H from the optical component, distance H being greater than distance J. A laser source manipulation mechanism exhibits a mechanical resolution of positioning the laser source. The mechanical resolution is less than a spatial resolution of laser energy at the target position as directed through the optical component. A vertical and a lateral index that intersect at an origin can be defined for the optical component. The manipulation mechanism can auto align laser aim through the origin during laser source motion. The laser source manipulation mechanism can include a mechanical index. The mechanical index can include a pivot point for laser source lateral motion and a reference point for laser source vertical motion. The target position can be located within an adverse environment including at least one of a high magnetic field, a vacuum system, a high pressure system, and a hazardous zone. The laser source and an electro-mechanical part of the manipulation mechanism can be located outside the adverse environment. The manipulation mechanism can include a Peaucellier linkage.

  4. Glass lasers.

    PubMed

    Snitzer, E

    1966-10-01

    After a general discussion of the merits of glass vs. crystals as host materials for laser ions, a summary is given of the various glass lasers. Because of its importance as an efficient, room temperature laser the properties of neodymium are considered in greater detail. This includes the nonlaser properties of Nd(3+) in glass, the spectral and temporal emission characteristics of Nd(3+) lasers, and Nd(3+) laser configurations. Separate sections deal with the other two room temperature lasers which use Yb(3+) or Er(3+). The problem of thermal stability of laser cavities is also discussed. Finally, a survey is given of the glasses that are useful as Faraday rotators. PMID:20057584

  5. Laser ignition

    DOEpatents

    Early, James W.; Lester, Charles S.

    2003-01-01

    In the apparatus of the invention, a first excitation laser or other excitation light source is used in tandem with an ignitor laser to provide a compact, durable, engine deployable fuel ignition laser system. Reliable fuel ignition is provided over a wide range of fuel conditions by using a single remote excitation light source for one or more small lasers located proximate to one or more fuel combustion zones. In a third embodiment, alternating short and long pulses of light from the excitation light source are directed into the ignitor laser. Each of the embodiments of the invention can be multiplexed so as to provide laser light energy sequentially to more than one ignitor laser.

  6. Evaluation of Color-Changing Effect and Complications After Nd: YAG Laser Application On Iris Surface

    PubMed Central

    Yildirim, Yildiray; Duzgun, Eyup; Kar, Taner; Sonmez, Murat; Kucukodaci, Zafer; Ersanli, Dilaver; Basoglu, Ayhan

    2016-01-01

    Background The aim of this study was to evaluate the color-changing effect and adverse effects after Nd: YAG laser application on the iris surface of rabbit eyes. Material/Methods The study was performed on right eyes of 12 pigmented rabbits. A laser device that produces frequency doubled 532 nm wavelength Nd: YAG laser with 900 μm spot diameter was used. The laser was applied in 3 sessions at 2-week intervals, at energy levels of 0.8 mJ in Group A and 1.5 mJ in Group B. Slit-lamp examinations and measurements of intraocular pressure (IOP) using a Tono-Pen were performed before and 1 day after each laser session. Iris thickness (IT) was measured at the beginning and the end using an ultrasonic biomicroscope. The eyes were enucleated for histopathologic examination on day 60. Results On the first day after each laser session, maximum grade 1 anterior chamber flare and cells were observed in both groups. In all eyes, flare and cells disappeared at the end of the first week. There was no significant difference in the IOP and IT values between measurements performed prior to and after laser sessions during the study (p>0.05). None of the eyes showed complications such as corneal edema, hypopyon, posterior synechia, transillumination defect, or pupillary defect. In histopathological examinations, reduction in pigment density was more profound in Group B compared to Group A, which was statistically significant (p<0.019). Conclusions There were no serious complications apart from mild transient inflammatory signs. Change in iris color was more evident at the end of the second month. PMID:26751845

  7. Laser ignition

    DOEpatents

    Early, James W.; Lester, Charles S.

    2002-01-01

    In the apparatus of the invention, a first excitation laser or other excitation light source is used in tandem with an ignitor laser to provide a compact, durable, engine deployable fuel ignition laser system. Reliable fuel ignition is provided over a wide range of fuel conditions by using a single remote excitation light source for one or more small lasers located proximate to one or more fuel combustion zones. In the embodiment of the invention claimed herein, the beam from the excitation light source is split with a portion of it going to the ignitor laser and a second portion of it being combined with either the first portion after a delay before injection into the ignitor laser.

  8. Bipolar transurethral enucleation and resection of the prostate versus bipolar resection of the prostate for prostates larger than 60gr: A retrospective study at a single academic tertiary care center

    PubMed Central

    Wei, Yong; Xu, Ning; Chen, Shao-Hao; Li, Xiao-Dong; Zheng, Qing-Shui; Lin, Yun-Zhi; Xue, Xue-Yi

    2016-01-01

    ABSTRACT Objective: To evaluate the efficacy and safety of bipolar transurethral enucleation and resection of the prostate (B-TUERP) versus bipolar transurethral resection of the prostate (B-TURP) in the treatment of prostates larger than 60g. Material and Methods: Clinical data for 270 BPH patients who underwent B-TUERP and 204 patients who underwent B-TURP for BPH from May 2007 to May 2013 at our center were retrospectively analyzed. Outcome measures included operative time, decreased hemoglobin level, total prostate specific antigen (TPSA), International Prostate Symptom Score (IPSS), maximal urinary flow rate (Qmax), quality of life (QoL) score, post void residual urine volume (RUV), bladder irrigation duration, hospital stay, and the weight of resected prostatic tissue. Other measures included perioperative complications including transurethral resection syndrome (TURS), hyponatremia, blood transfusion, bleeding requiring surgery, postoperative acute urinary retention, urine incontinence and urinary sepsis. Patients in both groups were followed for two years. Results: Compared with the B-TURP group, the B-TUERP group had shorter operative time, postoperative bladder irrigation duration and hospital stay, a greater amount of resected prostatic tissue, less postoperative hemoglobin decrease, better postoperative IPSS and Qmax, as well as lower incidences of hyponatremia, urinary sepsis, blood transfusion requirement, urine incontinence and reoperation (P<0.05 for all). Conclusions: B-TUERP is superior to B-TURP in the management of large volume BPH in terms of efficacy and safety, but this finding needs to be validated in further prospective, randomized, controlled studies. PMID:27564286

  9. Laser pyrometry

    NASA Technical Reports Server (NTRS)

    Stein, Alexander

    1988-01-01

    A method of determining the emissivity of a hot target from a laser-based reflectance measurement which is conducted simultaneously with a measurement of the target radiance is described. Once the correct radiance and emissivity are determined, one calculates the true target temperature from these parameters via the Planck equations. The design and performance of a laser pyrometer is described. The accuracy of laser pyrometry and the effect of ambient radiance are addressed.

  10. Laser ignition

    DOEpatents

    Early, James W.; Lester, Charles S.

    2002-01-01

    In the apparatus of the invention, a first excitation laser or other excitation light source capable of producing alternating beams of light having different wavelengths is used in tandem with one or more ignitor lasers to provide a compact, durable, engine deployable fuel ignition laser system. Reliable fuel ignition is provided over a wide range of fuel conditions by using the single remote excitation light source for pumping one or more small lasers located proximate to one or more fuel combustion zones with alternating wavelengths of light.

  11. Laser polishing

    NASA Astrophysics Data System (ADS)

    Temmler, A.; Willenborg, E.; Wissenbach, K.

    2012-03-01

    A new approach to polish metallic freeform surfaces is polishing by means of laser radiation. In this technology a thin surface layer is molten and the surface tension leads to a material flow from the peaks to the valleys. No material is removed but reallocated while molten. As the typical processing time is 1 min/cm2 laser polishing is up to 30 times faster than manual polishing. Reducing the roughness by laser polishing is achieved for several different materials such as hot work steels for the die and molding industries or titanium alloys for medical engineering. Enhancing the appearance of design surfaces is achieved by creating a dual-gloss effect by selective laser polishing (SLP). In comparison to conventional polishing processes laser polishing opens up the possibility of selective processing of small areas (< 0.1 mm2). A dual-gloss effect is based on a space-resolved change in surface roughness. In comparison to the initial surface the roughness of the laser polished surface is reduced significantly up to spatial wavelengths of 80 microns and therefore the gloss is raised considerably. The surface roughness is investigated by a spectral analysis which is achieved by a discrete convolution of the surface profile with a Gaussian loaded function. The surfaces roughness is split into discrete wavelength intervals and can be evaluated and optimized. Laser polishing is carried out by using a special tailored five-axis mechanical handling system, combined with a three axis laser scanning system and a fibre laser.

  12. Biocavity Lasers

    SciTech Connect

    Gourley, P.L.; Gourley, M.F.

    2000-10-05

    Laser technology has advanced dramatically and is an integral part of today's healthcare delivery system. Lasers are used in the laboratory analysis of human blood samples and serve as surgical tools that kill, burn or cut tissue. Recent semiconductor microtechnology has reduced the size o f a laser to the size of a biological cell or even a virus particle. By integrating these ultra small lasers with biological systems, it is possible to create micro-electrical mechanical systems that may revolutionize health care delivery.

  13. Laser apparatus

    DOEpatents

    Lewis, Owen; Stogran, Edmund M.

    1980-01-01

    Laser apparatus is described wherein an active laser element, such as the disc of a face-pumped laser, is mounted in a housing such that the weight of the element is supported by glass spheres which fill a chamber defined in the housing between the walls of the housing and the edges of the laser element. The uniform support provided by the spheres enable the chamber and the pump side of the laser element to be sealed without affecting the alignment or other optical properties of the laser element. Cooling fluid may be circulated through the sealed region by way of the interstices between the spheres. The spheres, and if desired also the cooling fluid may contain material which absorbs radiation at the wavelength of parasitic emissions from the laser element. These parasitic emissions enter the spheres through the interface along the edge surface of the laser element and it is desirable that the index of refraction of the spheres and cooling fluid be near the index of refraction of the laser element. Thus support, cooling, and parasitic suppression functions are all accomplished through the use of the arrangement.

  14. fs-lentotomie: changing the accommodation amplitude of presbyopic human lenses by fs laser pulses

    NASA Astrophysics Data System (ADS)

    Schumacher, S.; Oberheide, U.; Theuer, H.; Fromm, M.; Ripken, T.; Gerten, G.; Ertmer, W.; Lubatschowski, H.

    2007-07-01

    According to Helmholtz' theory of accommodation one of the mayor reasons for the development of presbyopia is the increasing sclerosis of the lens. One concept to overcome this hardening of the lens is to regain its flexibility by inducing gliding planes inside the lens. Femtosecond laser pulses are a suitable tool for this treatment. Showing in former work that we could increase the flexibility of enucleated porcine (ex vivo) lenses up to 25%, we focused our recent work on human autopsy lenses. The age of the human donors ranged between 20 and 70 years. For an evaluation of the gain in flexibility the lens' thickness was measured undertaking the Fisher's spinning test before and after laser treatment. Depending on the age and the quality of applied cutting pattern the lens thickness increased after treatment up to 0.4 mm leading to an theoretical increase of several dioptres of optical power. The flexibility could be increased up to 70 % compared to the measurements before treatment. Since the age of the human donors had a broad range, leading to different degrees of lens hardening, the variance of the measured flexibility changes was up to 30%. An addition the influence of the laser treatment onto the lens on the accommodation amplitude will be shown in a three dimensional finite-element simulation.

  15. First application of laser welding in clinical transplantation of the cornea

    NASA Astrophysics Data System (ADS)

    Pini, Roberto; Menabuoni, Luca; Starnotti, Lorenzo

    2001-05-01

    After a 4-year-long pre-clinical experimentation carried out at first on enucleated eyes and then on animal models, we applied a new procedure of laser welding of the cornea on voluntary patients. The welding technique is based on controlled irradiation of the cornea by diode laser radiation (805 nm) operating at low power (60-90 mW) in association with a photoenhancing chromophore applied locally. The welding effect is very effective and selective, because it takes place only in the cut where chromophore is present, while the contiguous tissue remains completely untouched. In the clinical phase, this technique was firstly tested in corneal cuts of increasing length on 25 patients subjected to facoemulsification of the cataract, by both sclero-corneal and corneal tunnels, and to extracapsular cataract extraction by sclero-corneal and corneal cuts. As previously confirmed by histological analysis performed on animal samples, we observed in humans too an early and effective healing process, with a sensible reduction of the post-operatory astigmatism. Based on these positive results, we finally arrived at the first application of diode laser- assisted corneal welding to penetrating keratoplasty (corneal transplantation), where this technique has been employed as far as now in 3 cases to substitute the application of the continuous suture.

  16. Heterodyne laser spectroscopy system

    DOEpatents

    Wyeth, Richard W.; Paisner, Jeffrey A.; Story, Thomas

    1990-01-01

    A heterodyne laser spectroscopy system utilizes laser heterodyne techniques for purposes of laser isotope separation spectroscopy, vapor diagnostics, processing of precise laser frequency offsets from a reference frequency, and provides spectral analysis of a laser beam.

  17. Heterodyne laser spectroscopy system

    DOEpatents

    Wyeth, Richard W.; Paisner, Jeffrey A.; Story, Thomas

    1989-01-01

    A heterodyne laser spectroscopy system utilizes laser heterodyne techniques for purposes of laser isotope separation spectroscopy, vapor diagnostics, processing of precise laser frequency offsets from a reference frequency and the like, and provides spectral analysis of a laser beam.

  18. Lasers in Cancer Treatment

    MedlinePlus

    ... Cancer Treatment On This Page What is laser light? What is laser therapy, and how is it ... future hold for laser therapy? What is laser light? The term “ laser ” stands for light amplification by ...

  19. Laser Therapy

    MedlinePlus

    ... Non-ablative Laser Rejuvenation Non-invasive Body Contouring Treatments Skin Cancer Skin Cancer Information Free Skin Cancer Screenings Skin ... Non-ablative Laser Rejuvenation Non-invasive Body Contouring Treatments Skin Cancer Skin Cancer Information Free Skin Cancer Screenings Skin ...

  20. Laser device

    DOEpatents

    Scott, Jill R.; Tremblay, Paul L.

    2008-08-19

    A laser device includes a virtual source configured to aim laser energy that originates from a true source. The virtual source has a vertical rotational axis during vertical motion of the virtual source and the vertical axis passes through an exit point from which the laser energy emanates independent of virtual source position. The emanating laser energy is collinear with an orientation line. The laser device includes a virtual source manipulation mechanism that positions the virtual source. The manipulation mechanism has a center of lateral pivot approximately coincident with a lateral index and a center of vertical pivot approximately coincident with a vertical index. The vertical index and lateral index intersect at an index origin. The virtual source and manipulation mechanism auto align the orientation line through the index origin during virtual source motion.

  1. Technical aspects of the piezo, laser-assisted, and conventional methods for nuclear transfer of mouse oocytes and their efficiency and efficacy: Piezo minimizes damage of the ooplasmic membrane at injection.

    PubMed

    Chen, Shee-Uan; Chao, Kuang-Han; Chang, Chia-Yi; Hsieh, Fon-Jou; Ho, Hong-Nerng; Yang, Yu-Shih

    2004-04-01

    Assessment of the advantages and disadvantages of the piezo, laser, and conventional methods for nuclear transfer has remained elusive. Furthermore, although the piezo method had been used by some investigators for research of sperm injection and nuclear transfer for several years, many researchers have failed to operate the technique smoothly and achieve reproducible results. The procedures of nuclear transfer using piezo were ascertained and described in detail. Mouse oocytes were enucleated, and injected with cumulus cells using the piezo, laser, or conventional methods. We investigated the time needed and survival of nuclear transfer. Development was compared among the three methods and parthenogenetic control specimens. The average time of nuclear transfer for each oocyte was significantly shorter using the piezo (118 +/- 9 s) and laser methods (120 +/- 11 s) than using the conventional method (170 +/- 11 s). The damage rate was smaller for the piezo group (10%) than the laser (37%) and conventional (40%) groups. The percentages of blastocyst formation (14%, 12%, and 11%) and the number of nuclei of blastocysts (54 +/- 13, 51 +/- 11, and 52 +/- 12) were similar among the piezo, laser, and conventional groups, but significantly lower than for the control group (83%, 105 +/- 14). The piezo technique is more efficient than the conventional method for nuclear transfer. The laser method is easy to operate, but the equipment is expensive. In addition, piezo induced fewer traumas while breaking the membrane than the aspiration techniques used in the laser and conventional methods. PMID:15039993

  2. Autokeratomileusis Laser

    NASA Astrophysics Data System (ADS)

    Kern, Seymour P.

    1987-03-01

    Refractive defects such as myopia, hyperopia, and astigmatism may be corrected by laser milling of the cornea. An apparatus combining automatic refraction/keratometry and an excimer type laser for precision reshaping of corneal surfaces has been developed for testing. When electronically linked to a refractometer or keratometer or holographic imaging device, the laser is capable of rapidly milling or ablating corneal surfaces to preselected dioptric power shapes without the surgical errors characteristic of radial keratotomy, cryokeratomileusis or epikeratophakia. The excimer laser simultaneously generates a synthetic Bowman's like layer or corneal condensate which appears to support re-epithelialization of the corneal surface. An electronic feedback arrangement between the measuring instrument and the laser enables real time control of the ablative milling process for precise refractive changes in the low to very high dioptric ranges. One of numerous options is the use of a rotating aperture wheel with reflective portions providing rapid alternate ablation/measurement interfaced to both laser and measurement instrumentation. The need for the eye to be fixated is eliminated or minimized. In addition to reshaping corneal surfaces, the laser milling apparatus may also be used in the process of milling both synthetic and natural corneal inlays for lamellar transplants.

  3. Laser propulsion

    NASA Technical Reports Server (NTRS)

    Rom, F. E.; Putre, H. A.

    1972-01-01

    The use of an earth-based high-power laser beam to provide energy for earth-launched rocket vehicle is investigated. The laser beam energy is absorbed in an opaque propellant gas and is converted to high-specific-impulse thrust by expanding the heated propellant to space by means of a nozzle. This laser propulsion scheme can produce specific impulses of several thousand seconds. Payload to gross-weight fractions about an order of magnitude higher than those for conventional chemical earth-launched vehicles appear possible. There is a potential for a significant reduction in cost per payload mass in earth orbit.

  4. Laser goniometer

    DOEpatents

    Fairer, George M.; Boernge, James M.; Harris, David W.; Campbell, DeWayne A.; Tuttle, Gene E.; McKeown, Mark H.; Beason, Steven C.

    1993-01-01

    The laser goniometer is an apparatus which permits an operator to sight along a geologic feature and orient a collimated lamer beam to match the attitude of the feature directly. The horizontal orientation (strike) and the angle from horizontal (dip), are detected by rotary incremental encoders attached to the laser goniometer which provide a digital readout of the azimuth and tilt of the collimated laser beam. A microprocessor then translates the square wave signal encoder outputs into an ASCII signal for use by data recording equipment.

  5. Explosive laser

    DOEpatents

    Robinson, C.P.; Jensen, R.J.; Davis, W.C.; Sullivan, J.A.

    1975-09-01

    This patent relates to a laser system wherein reaction products from the detonation of a condensed explosive expand to form a gaseous medium with low translational temperature but high vibration population. Thermal pumping of the upper laser level and de-excitation of the lower laser level occur during the expansion, resulting in a population inversion. The expansion may be free or through a nozzle as in a gas-dynamic configuration. In one preferred embodiment, the explosive is such that its reaction products are CO$sub 2$ and other species that are beneficial or at least benign to CO$sub 2$ lasing. (auth)

  6. Chemical lasers

    NASA Astrophysics Data System (ADS)

    Khariton, Y.

    1984-08-01

    The application and the advances of quantum electronics, specifically, of optical quantum generators lasers is reviewed. Materials are cut, their surfaces are machined, chemical transformations of substances are carried out, surgical operations are performed, data are transmitted, three dimensional images are produced and the content of microimpurities, in the atmosphere, are analyzed by use of a beam. Laser technology is used in conducting investigations in the most diverse fields of the natural and technical sciences from controlled thermonuclear fusion to genetics. Many demands are placed on lasers as sources of light energy. The importance of low weight, compactness of the optical generator and the efficiency of energy conversion processes is emphasized.

  7. Laser arthroscopy.

    PubMed

    Sherk, H H; Lane, G J; Black, J D

    1992-09-01

    Lasers have become widely used in several medical and surgical disciplines. In ophthalmology and plastic surgery, their use has permitted the development of therapeutic modalities that would have been otherwise impossible. In such specialties as gynecology and general surgery, lasers provide advantages that make certain procedures more convenient and easier to perform. In contrast, orthopaedic surgeons have, to date, been slow to accept these devices into the therapeutic armamentarium. The purpose of this paper is to describe the status of laser use in the orthopaedic subspecialty of arthroscopy. PMID:1437258

  8. Chemically assisted somatic cell nuclear transfer without micromanipulator in the goat: effects of demecolcine, cytochalasin-B, and MG-132 on the efficiency of a manual method of oocyte enucleation using a pulled Pasteur pipette.

    PubMed

    Hosseini, S M; Hajian, M; Forouzanfar, M; Ostadhosseini, S; Moulavi, F; Ghanaei, H R; Gourbai, H; Shahverdi, A H; Vosough, A D; Nasr-Esfahani, M H

    2015-07-01

    The present study aimed to facilitate widespread application of a previously described manual method of somatic cell nuclear transfer (SCNT) by investigating the effects of demecolcine (a microtubule-depolymerizing chemical), cytochalasin-B (a microfilament-depolymerizing chemical: 2.5μg/ml for 15min) and MG-132 (a proteasome inhibitor chemical) on the (i) incidence of cytoplasmic protrusion of MII chromosomes, (ii) improvement of manual oocyte enucleation, and (iii) in vitro and in vivo developmental competence of SCNT embryos in the goat. Following in vitro maturation, around 65% of goat oocytes contained a characteristic cytoplasmic protrusion of MII-chromosomes. Treatment with demecolcine (0.4μg/ml for 30min) significantly increased this rate to 92.2±4.5%. Treatment with MG-132 (2μM for 30min) could not improve this rate when used alone (61.4±11.5%), but when combined with demecolcine (86.4±8.1%). Treatment with cytochalasin-B completely suppressed this rate whenever used, either alone (7.7±5.1%) or in combination with demecolcine (3.9±1.3%). In a direct comparison, there was no significant difference in quantity and quality of embryos propagated by the manual vs. micromanipulation-based methods of SCNT (cleavage: 85.3±4.5 vs. 89.5±8.9%, blastocyst: 19.5±4.3 vs. 24.3±4.4%, grade 1 and 2 blastocyst: 33.8±7.1 vs. 29.5±6.3%, total cell count: 125±11.1 vs. 122±10.5, respectively). Furthermore, development to live kids at term was not significant between the two SCNT methods. From both technical and economical points of view, the overall in vitro and in vivo efficiency of this manual method of SCNT proved it a simple, fast and efficient alternative for large scale production of cloned goats. PMID:25956201

  9. Laser barometer

    SciTech Connect

    Abercrombie, K.R.; Shiels, D.; Rash, T.

    1998-04-01

    This paper describes an invention of a pressure measuring instrument which uses laser radiation to sense the pressure in an enclosed environment by means of measuring the change in refractive index of a gas - which is pressure dependent.

  10. Laser fusion

    SciTech Connect

    Smit, W.A.; Boskma, P.

    1980-12-01

    Unrestricted laser fusion offers nations an opportunity to circumvent arms control agreements and develop thermonuclear weapons. Early laser weapons research sought a clean radiation-free bomb to replace the fission bomb, but this was deceptive because a fission bomb was needed to trigger the fusion reaction and additional radioactivity was induced by generating fast neutrons. As laser-implosion experiments focused on weapons physics, simulating weapons effects, and applications for new weapons, the military interest shifted from developing a laser-ignited hydrogen bomb to more sophisticated weapons and civilian applications for power generation. Civilian and military research now overlap, making it possible for several countries to continue weapons activities and permitting proliferation of nuclear weapons. These countries are reluctant to include inertial confinement fusion research in the Non-Proliferation Treaty. 16 references. (DCK)

  11. Laser Research

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Eastman Kodak Company, Rochester, New York is a broad-based firm which produces photographic apparatus and supplies, fibers, chemicals and vitamin concentrates. Much of the company's research and development effort is devoted to photographic science and imaging technology, including laser technology. Eastman Kodak is using a COSMIC computer program called LACOMA in the analysis of laser optical systems and camera design studies. The company reports that use of the program has provided development time savings and reduced computer service fees.

  12. Laser Technology

    NASA Technical Reports Server (NTRS)

    1989-01-01

    Amoco Laser Company, a subsidiary of Amoco Corporation, has developed microlasers for the commercial market based on a JPL concept for optical communications over interplanetary distances. Lasers emit narrow, intense beams of light or other radiation. The beams transmit communication signals, drill, cut or melt materials or remove diseased body tissue. The microlasers cover a broad portion of the spectrum, and performance is improved significantly. Current applications include medical instrumentation, color separation equipment, telecommunications, etc.

  13. Laser optomechanics.

    PubMed

    Yang, Weijian; Gerke, Stephen Adair; Ng, Kar Wei; Rao, Yi; Chase, Christopher; Chang-Hasnain, Connie J

    2015-01-01

    Cavity optomechanics explores the interaction between optical field and mechanical motion. So far, this interaction has relied on the detuning between a passive optical resonator and an external pump laser. Here, we report a new scheme with mutual coupling between a mechanical oscillator supporting the mirror of a laser and the optical field generated by the laser itself. The optically active cavity greatly enhances the light-matter energy transfer. In this work, we use an electrically-pumped vertical-cavity surface-emitting laser (VCSEL) with an ultra-light-weight (130 pg) high-contrast-grating (HCG) mirror, whose reflectivity spectrum is designed to facilitate strong optomechanical coupling, to demonstrate optomechanically-induced regenerative oscillation of the laser optomechanical cavity. We observe >550 nm self-oscillation amplitude of the micromechanical oscillator, two to three orders of magnitude larger than typical, and correspondingly a 23 nm laser wavelength sweep. In addition to its immediate applications as a high-speed wavelength-swept source, this scheme also offers a new approach for integrated on-chip sensors. PMID:26333804

  14. Laser Angioplasty

    NASA Technical Reports Server (NTRS)

    1990-01-01

    The principal method of dealing with coronary artery blockage is bypass surgery. A non-surgical alternative available to some patients is balloon angioplasty. For several years, medical researchers have been exploring another alternative that would help a wider circle of patients than the balloon treatment and entail less risk than bypass surgery. A research group is on the verge of an exciting development: laser angioplasty with a 'cool' type of laser, called an excimer laser, that does not damage blood vessel walls and offers non-surgical cleansing of clogged arteries with extraordinary precision. The system is the Dymer 200+ Excimer Laser Angioplasty System, developed by Advanced Intraventional Systems. Used in human clinical tests since 1987, the system is the first fully integrated 'cool' laser capable of generating the requisite laser energy and delivering the energy to target arteries. Thirteen research hospitals in the U.S. have purchased Dymer 200+ systems and used them in clinical trials in 121 peripheral and 555 coronary artery cases. The success rate in opening blocked coronary arteries is 85 percent, with fewer complications than in balloon angioplasty. Food and Drug Administration approval for the system is hoped for in the latter part of 1990. * Advanced Intraventional Systems became Spectranetics in 1994 and discontinued the product.

  15. Laser optomechanics

    NASA Astrophysics Data System (ADS)

    Yang, Weijian; Adair Gerke, Stephen; Wei Ng, Kar; Rao, Yi; Chase, Christopher; Chang-Hasnain, Connie J.

    2015-09-01

    Cavity optomechanics explores the interaction between optical field and mechanical motion. So far, this interaction has relied on the detuning between a passive optical resonator and an external pump laser. Here, we report a new scheme with mutual coupling between a mechanical oscillator supporting the mirror of a laser and the optical field generated by the laser itself. The optically active cavity greatly enhances the light-matter energy transfer. In this work, we use an electrically-pumped vertical-cavity surface-emitting laser (VCSEL) with an ultra-light-weight (130 pg) high-contrast-grating (HCG) mirror, whose reflectivity spectrum is designed to facilitate strong optomechanical coupling, to demonstrate optomechanically-induced regenerative oscillation of the laser optomechanical cavity. We observe >550 nm self-oscillation amplitude of the micromechanical oscillator, two to three orders of magnitude larger than typical, and correspondingly a 23 nm laser wavelength sweep. In addition to its immediate applications as a high-speed wavelength-swept source, this scheme also offers a new approach for integrated on-chip sensors.

  16. Laser optomechanics

    PubMed Central

    Yang, Weijian; Adair Gerke, Stephen; Wei Ng, Kar; Rao, Yi; Chase, Christopher; Chang-Hasnain, Connie J.

    2015-01-01

    Cavity optomechanics explores the interaction between optical field and mechanical motion. So far, this interaction has relied on the detuning between a passive optical resonator and an external pump laser. Here, we report a new scheme with mutual coupling between a mechanical oscillator supporting the mirror of a laser and the optical field generated by the laser itself. The optically active cavity greatly enhances the light-matter energy transfer. In this work, we use an electrically-pumped vertical-cavity surface-emitting laser (VCSEL) with an ultra-light-weight (130 pg) high-contrast-grating (HCG) mirror, whose reflectivity spectrum is designed to facilitate strong optomechanical coupling, to demonstrate optomechanically-induced regenerative oscillation of the laser optomechanical cavity. We observe >550 nm self-oscillation amplitude of the micromechanical oscillator, two to three orders of magnitude larger than typical, and correspondingly a 23 nm laser wavelength sweep. In addition to its immediate applications as a high-speed wavelength-swept source, this scheme also offers a new approach for integrated on-chip sensors. PMID:26333804

  17. Laser therapy for cancer

    MedlinePlus

    ... this page: //medlineplus.gov/ency/patientinstructions/000905.htm Laser therapy for cancer To use the sharing features ... Lasers are also used on the skin. How Laser Therapy is Used Laser therapy can be used ...

  18. Tunable solid state lasers

    SciTech Connect

    Hammerling, R.; Budgor, A.B.; Pinto, A.

    1985-01-01

    This book presents the papers given at a conference on solid state lasers. Topics considered at the conference included transition-metal-doped lasers, line-narrowed alexandrite lasers, NASA specification, meteorological lidars, laser materials spectroscopy, laser pumped single pass gain, vibronic laser materials growth, crystal growth methods, vibronic laser theory, cross-fertilization through interdisciplinary fields, and laser action of color centers in diamonds.

  19. Excimer lasers

    NASA Technical Reports Server (NTRS)

    Palmer, A. J.; Hess, L. D.; Stephens, R. R.

    1976-01-01

    A theoretical and experimental investigation into the possibility of achieving CW discharge pumped excimer laser oscillation is reported. Detailed theoretical modeling of capillary discharge pumping of the XeF and KXe and K2 excimer systems was carried out which predicted the required discharge parameters for reaching laser threshold on these systems. Capillary discharge pumping of the XeF excimer system was investigated experimentally. The experiments revealed a lower excimer level population density than predicted theoretically by about an order of magnitude. The experiments also revealed a fluorine consumption problem in the discharge in agreement with theory.

  20. Airborne laser

    NASA Astrophysics Data System (ADS)

    Lamberson, Steven E.

    2002-06-01

    The US Air Force Airborne Laser (ABL) is an airborne, megawatt-class laser system with a state-of-the-art atmospheric compensation system to destroy enemy ballistic missiles at long ranges. This system will provide both deterrence and defense against the use of such weapons during conflicts. This paper provides an overview of the ABL weapon system including: the notional operational concept, the development approach and schedule, the overall aircraft configuration, the technologies being incorporated in the ABL, and the risk reduction approach being utilized to ensure program success.

  1. Laser Resonator

    NASA Technical Reports Server (NTRS)

    Harper, L. L. (Inventor)

    1983-01-01

    An optical resonator cavity configuration has a unitary mirror with oppositely directed convex and concave reflective surfaces disposed into one fold and concertedly reversing both ends of a beam propagating from a laser rod disposed between two total internal reflection prisms. The optical components are rigidly positioned with perpendicularly crossed virtual rooflines by a compact optical bed. The rooflines of the internal reflection prisms, are arranged perpendicularly to the axis of the laser beam and to the optical axes of the optical resonator components.

  2. Laser barometer

    DOEpatents

    Abercrombie, Kevin R.; Shiels, David; Rash, Tim

    2001-02-06

    A pressure measuring instrument that utilizes the change of the refractive index of a gas as a function of pressure and the coherent nature of a laser light to determine the barometric pressure within an environment. As the gas pressure in a closed environment varies, the index of refraction of the gas changes. The amount of change is a function of the gas pressure. By illuminating the gas with a laser light source, causing the wavelength of the light to change, pressure can be quantified by measuring the shift in fringes (alternating light and dark bands produced when coherent light is mixed) in an interferometer.

  3. Laser Cladding

    NASA Astrophysics Data System (ADS)

    Lepski, Dietrich; Brückner, Frank

    Laser cladding is a modern technology whose uses include, for example, the creation of protective coatings to reduce wear and corrosion on engine parts and tools. The aircraft and automotive industries are examples of industries in which it is much used. This account considers the theory of a number of aspects of the process in detail. The first to be studied is the interaction of the laser beam directly with the powder that is being deposited; the effects of gravity, beam shadowing, and particle heating are investigated. This is followed by a discussion of the mechanisms by which the particles adhere to the surface of the work piece and are absorbed into it. In order to understand the process, a study of the melt pool and the associated temperature distribution is necessary; it is then possible to infer the final bead geometry. An inevitable consequence of a thermal process such as laser cladding is the induced thermal stress and resulting distortion of the work piece. The fundamentals are discussed, a numerical model presented and in addition a simple heuristic model is given. The use of induction-assisted laser cladding as a means of preventing the formation of cracks is discussed.

  4. Excimer lasers

    NASA Technical Reports Server (NTRS)

    Palmer, A. J.; Hess, L. D.; Stephens, R. R.; Pepper, D. M.

    1977-01-01

    The results of a two-year investigation into the possibility of developing continuous wave excimer lasers are reported. The program included the evaluation and selection of candidate molecular systems and discharge pumping techniques. The K Ar/K2 excimer dimer molecules and the xenon fluoride excimer molecule were selected for study; each used a transverse and capillary discharges pumping technique. Experimental and theoretical studies of each of the two discharge techniques applied to each of the two molecular systems are reported. Discharge stability and fluorine consumption were found to be the principle impediments to extending the XeF excimer laser into the continuous wave regime. Potassium vapor handling problems were the principal difficulty in achieving laser action on the K Ar/K2 system. Of the four molecular systems and pumping techniques explored, the capillary discharge pumped K Ar/K2 system appears to be the most likely candidate for demonstrating continuous wave excimer laser action primarily because of its predicted lower pumping threshold and a demonstrated discharge stability advantage.

  5. Laser iridotomy.

    PubMed

    Perkins, E S

    1970-06-01

    A ruby laser has been used to produce a permeable lesion in the iris to establish a communication between the anterior and posterior chambers. In a preliminary study in nine patients the technique gave satisfactory results in the prophylactic treatment of four cases of incipient closed-angle glaucoma and of two cases of iris bombé following uveitis. PMID:5526615

  6. Laser altimeter

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The development of a laser altimeter for use in the Apollo Lunar Orbital Experiments mission is discussed. The altimeter provides precise measurement of an Apollo vehicle above the lunar surface from an orbit of 40 to 80 nautical miles. The technical characteristics of the altimeter are described. Management of the altimeter development program is analyzed.

  7. Laser capture.

    PubMed

    Potter, S Steven; Brunskill, Eric W

    2012-01-01

    This chapter describes detailed methods used for laser capture microdissection (LCM) of discrete subpopulations of cells. Topics covered include preparing tissue blocks, cryostat sectioning, processing slides, performing the LCM, and purification of RNA from LCM samples. Notes describe the fine points of each operation, which can often mean the difference between success and failure. PMID:22639264

  8. Nanowire Lasers

    NASA Astrophysics Data System (ADS)

    Couteau, C.; Larrue, A.; Wilhelm, C.; Soci, C.

    2015-05-01

    We review principles and trends in the use of semiconductor nanowires as gain media for stimulated emission and lasing. Semiconductor nanowires have recently been widely studied for use in integrated optoelectronic devices, such as light-emitting diodes (LEDs), solar cells, and transistors. Intensive research has also been conducted in the use of nanowires for subwavelength laser systems that take advantage of their quasione- dimensional (1D) nature, flexibility in material choice and combination, and intrinsic optoelectronic properties. First, we provide an overview on using quasi-1D nanowire systems to realize subwavelength lasers with efficient, directional, and low-threshold emission. We then describe the state of the art for nanowire lasers in terms of materials, geometry, andwavelength tunability.Next,we present the basics of lasing in semiconductor nanowires, define the key parameters for stimulated emission, and introduce the properties of nanowires. We then review advanced nanowire laser designs from the literature. Finally, we present interesting perspectives for low-threshold nanoscale light sources and optical interconnects. We intend to illustrate the potential of nanolasers inmany applications, such as nanophotonic devices that integrate electronics and photonics for next-generation optoelectronic devices. For instance, these building blocks for nanoscale photonics can be used for data storage and biomedical applications when coupled to on-chip characterization tools. These nanoscale monochromatic laser light sources promise breakthroughs in nanophotonics, as they can operate at room temperature, can potentially be electrically driven, and can yield a better understanding of intrinsic nanomaterial properties and surface-state effects in lowdimensional semiconductor systems.

  9. Laser weapons. II - Strategic laser weapons

    NASA Astrophysics Data System (ADS)

    Hecht, J.

    1982-07-01

    Potential strategic missions for laser weapons, particularly those involving space-based lasers, are discussed. The functions of space-based lasers and the history of their conceptual development are summarized, and the problems of implementing such systems, including the building of a suitable laser and power source, and resolving the problem of optics, are discussed. Ongoing development programs are described, and the contrasting views of the necessity and usefulness of strategic laser systems are set forth.

  10. Laser radiometer

    SciTech Connect

    Stein, A.; Kaldor, A.; Rabinowitz, P.

    1983-11-29

    The present invention teaches a unique laser radiometer capable of accurately measuring the radiation temperature of a radiant surface and independently measuring the surface's emissivity. A narrow-band radiometer is combined with a laser reflectometer to measure concurrently radiance and emissivity of a remote, hot surface. Together, radiance and emissivity yield the true surface temperature of the remote target. A narrow receiver bandwidth is attained by one of two methods; (a) heterodyne detection or (b) optical filtering. A direct measurement of emissivity is used to adjust the value obtained for the thermal radiation signal to substantially enhance the accuracy of the temperature measurement for a given subject surface. The technique provides substantially high detection sensitivity over a very narrow spectral bandwidth.

  11. Heterodyne laser diagnostic system

    DOEpatents

    Globig, Michael A.; Johnson, Michael A.; Wyeth, Richard W.

    1990-01-01

    The heterodyne laser diagnostic system includes, in one embodiment, an average power pulsed laser optical spectrum analyzer for determining the average power of the pulsed laser. In another embodiment, the system includes a pulsed laser instantaneous optical frequency measurement for determining the instantaneous optical frequency of the pulsed laser.

  12. Infrared Lasers in Chemistry.

    ERIC Educational Resources Information Center

    John, Phillip

    1982-01-01

    Selected infrared laser chemistry topics are discussed including carbon dioxide lasers, infrared quanta and molecules, laser-induced chemistry, structural isomerization (laser purification, sensitized reactions, and dielectric breakdown), and fundamental principles of laser isotope separation, focusing on uranium isotope separation. (JN)

  13. Making a Laser Level

    ERIC Educational Resources Information Center

    Hawkins, Harry

    2004-01-01

    This article describes how to construct a laser level. This laser level can be made using a typical 4' (or shorter) bubble level and a small laser point. The laser unit is detachable, so the bubble level can also be used in the conventional way. However, the laser level works better than a simple bubble level. Making this inexpensive device is an…

  14. Project LASER

    NASA Technical Reports Server (NTRS)

    1990-01-01

    NASA formally launched Project LASER (Learning About Science, Engineering and Research) in March 1990, a program designed to help teachers improve science and mathematics education and to provide 'hands on' experiences. It featured the first LASER Mobile Teacher Resource Center (MTRC), is designed to reach educators all over the nation. NASA hopes to operate several MTRCs with funds provided by private industry. The mobile unit is a 22-ton tractor-trailer stocked with NASA educational publications and outfitted with six work stations. Each work station, which can accommodate two teachers at a time, has a computer providing access to NASA Spacelink. Each also has video recorders and photocopy/photographic equipment for the teacher's use. MTRC is only one of the five major elements within LASER. The others are: a Space Technology Course, to promote integration of space science studies with traditional courses; the Volunteer Databank, in which NASA employees are encouraged to volunteer as tutors, instructors, etc; Mobile Discovery Laboratories that will carry simple laboratory equipment and computers to provide hands-on activities for students and demonstrations of classroom activities for teachers; and the Public Library Science Program which will present library based science and math programs.

  15. Laser nitriding and laser carburizing of surfaces

    NASA Astrophysics Data System (ADS)

    Schaaf, Peter

    2003-11-01

    Laser irradiation of surfaces with short pulses in reactive atmospheres (nitrogen, methane) can lead to very effective nitrification and carburization via complicated laser-surface-gas-plasma-interactions. This laser nitriding and laser carburizing and their basic underlying phenomena will be presented and partly explained by results of example materials (iron, titanium, aluminum, silicon) where nitride and carbide coatings can be formed by fast and easily by Excimer Laser, Nd:YAG laser, Free Electron Laser and also by femtosecond Ti:sapphire laser. This implies laser pulse durations from the nanosecond to the femtosecond regime and wavelengths from ultra-violet to infrared. The resulting surfaces, thin films, coatings and their properties are investigated by combining Mossbauer Spectroscopy, x-ray diffraction, x-ray absorption spectroscopy, Nanoindentation, Resonant Nuclear Reaction Analysis, and Rutherford Backscattering Spectroscopy.

  16. Holmium laser pumped with a neodymium laser

    SciTech Connect

    Bowman, S.R.; Rabinovich, W.S.

    1991-07-30

    This patent describes a solid-state laser device. It comprises a holmium laser having a first host material doped with an amount of holmium ions sufficient to produce an output laser emission at about 3 {mu}m when the holmium ions in the holmium laser are pumped by a pump beam at a wavelength of about 1.1 {mu}m; and neodymium laser pump source means for supplying a pump beam to pump the holmium ions in the holmium laser at a wavelength of about 1.1 {mu}m.

  17. Mars Observer Laser Altimeter: laser transmitter.

    PubMed

    Afzal, R S

    1994-05-20

    The Mars Observer Laser Altimeter utilizes a space-qualified diode-laser-pumped Q-switched Nd:YAG laser transmitter. A simple numerical model of the laser energetics is presented, which predicts the pulse energy and pulse width. Comparisons with the measured data available are made. The temperature dependence of the laser transmitter is also predicted. This dependence prediction is particularly important in determining the operational temperature range of the transmitter. Knowing the operational temperature range is especially important for a passive, thermally controlled laser operating in space. PMID:20885685

  18. Hypersonic gasdynamic laser system

    SciTech Connect

    Foreman, K.M.; Maciulaitis, A.

    1990-05-22

    This patent describes a visible, or near to mid infra-red, hypersonic gas dynamic laser system. It comprises: a hypersonic vehicle for carrying the hypersonic gas dynamic laser system, and also providing high energy ram air for thermodynamic excitation and supply of the laser gas; a laser cavity defined within the hypersonic vehicle and having a laser cavity inlet for the laser cavity formed by an opening in the hypersonic vehicle, such that ram air directed through the laser cavity opening supports gas dynamic lasing operations at wavelengths less than 10.6{mu} meters in the laser cavity; and an optical train for collecting the laser radiation from the laser cavity and directing it as a substantially collimated laser beam to an output aperture defined by an opening in the hypersonic vehicle to allow the laser beam to be directed against a target.

  19. Laser therapy (image)

    MedlinePlus

    A laser is used for many medical purposes. Because the laser beam is so small and precise, it enables ... without injuring surrounding tissue. Some uses of the laser are retinal surgery, excision of lesions, and cauterization ...

  20. Laser-Driven Fusion.

    ERIC Educational Resources Information Center

    Gibson, A. F.

    1980-01-01

    Discusses the present status and future prospects of laser-driven fusion. Current research (which is classified under three main headings: laser-matter interaction processes, compression, and laser development) is also presented. (HM)

  1. Lasers in Medicine.

    ERIC Educational Resources Information Center

    Hill, P. D.

    1989-01-01

    Described are the characteristics of the laser and its effects on the body. Discussed are examples of laser treatments, including angioplasty, ophthalmology, and dermatology. A discussion of lasers of clinical interest and their applications is presented. (YP)

  2. Laser accidents: Being Prepared

    SciTech Connect

    Barat, K

    2003-01-24

    The goal of the Laser Safety Officer and any laser safety program is to prevent a laser accident from occurring, in particular an injury to a person's eyes. Most laser safety courses talk about laser accidents, causes, and types of injury. The purpose of this presentation is to present a plan for safety offices and users to follow in case of accident or injury from laser radiation.

  3. New laser protective eyewear

    NASA Astrophysics Data System (ADS)

    McLear, Mark

    1996-04-01

    Laser technology has significantly impacted our everyday life. Lasers are now used to correct your vision, clear your arteries, and are used in the manufacturing of such diverse products as automobiles, cigarettes, and computers. Lasers are no longer a research tool looking for an application. They are now an integral part of manufacturing. In the case of Class IV lasers, this explosion in laser applications has exposed thousands of individuals to potential safety hazards including eye damage. Specific protective eyewear designed to attenuate the energy of the laser beam below the maximum permissible exposure is required for Class 3B and Class IV lasers according to laser safety standards.

  4. Laser satellite power systems

    SciTech Connect

    Walbridge, E.W.

    1980-01-01

    A laser satellite power system (SPS) converts solar power captured by earth-orbiting satellites into electrical power on the earth's surface, the satellite-to-ground transmission of power being effected by laser beam. The laser SPS may be an alternative to the microwave SPS. Microwaves easily penetrate clouds while laser radiation does not. Although there is this major disadvantage to a laser SPS, that system has four important advantages over the microwave alternative: (1) land requirements are much less, (2) radiation levels are low outside the laser ground stations, (3) laser beam sidelobes are not expected to interfere with electromagnetic systems, and (4) the laser system lends itself to small-scale demonstration. After describing lasers and how they work, the report discusses the five lasers that are candidates for application in a laser SPS: electric discharge lasers, direct and indirect solar pumped lasers, free electron lasers, and closed-cycle chemical lasers. The Lockheed laser SPS is examined in some detail. To determine whether a laser SPS will be worthy of future deployment, its capabilities need to be better understood and its attractiveness relative to other electric power options better assessed. First priority should be given to potential program stoppers, e.g., beam attenuation by clouds. If investigation shows these potential program stoppers to be resolvable, further research should investigate lasers that are particularly promising for SPS application.

  5. Laser Stabilization

    SciTech Connect

    Hall, John L.; Taubman, Matthew S.; Ye, Jun

    2010-01-01

    This book chapter covers the basics of the field of stabilizing lasers to optical frequency references such as optical cavities and molecular transitions via the application of servo control systems. These discussions are given with reference to the real-life frequency metrology experienced in Hall-Labs (now Ye-Labs), JILA, University of Colorado. The subjects covered include: the basics of control system stability, a discussion of both the theoretical and experimental limitations, an outline of optical cavity susceptibility to environmental noise, and a brief introduction to the use and limitations of molecular transitions as frequency references.

  6. Laser biophotonics

    NASA Astrophysics Data System (ADS)

    Bashkatov, A. N.; Genina, E. A.; Priezzhev, A. V.; Tuchin, V. V.

    2016-06-01

    This issue of Quantum Electronics presents the papers that reflect the state-of-the-art of laser technologies used in biomedical studies and medical practice. Among the new technologies, one can note the methods of correlation and Doppler spectroscopy, as well as THz spectroscopy, in which biologically significant molecules are characterised by specific resonances. The latter topic is considered in the paper by Nazarov et al., where the dielectric function of aqueous solutions of glucose and albumin is studied using pulsed THz spectroscopy.

  7. Laser Propulsion - Quo Vadis

    SciTech Connect

    Bohn, Willy L.

    2008-04-28

    First, an introductory overview of the different types of laser propulsion techniques will be given and illustrated by some historical examples. Second, laser devices available for basic experiments will be reviewed ranging from low power lasers sources to inertial confinement laser facilities. Subsequently, a status of work will show the impasse in which the laser propulsion community is currently engaged. Revisiting the basic relations leads to new avenues in ablative and direct laser propulsion for ground based and space based applications. Hereby, special attention will be devoted to the impact of emerging ultra-short pulse lasers on the coupling coefficient and specific impulse. In particular, laser sources and laser propulsion techniques will be tested in microgravity environment. A novel approach to debris removal will be discussed with respect to the Satellite Laser Ranging (SRL) facilities. Finally, some non technical issues will be raised aimed at the future prospects of laser propulsion in the international community.

  8. Studies on lasers and laser devices

    NASA Technical Reports Server (NTRS)

    Harris, S. E.; Siegman, A. E.; Young, J. F.

    1983-01-01

    The goal of this grant was to study lasers, laser devices, and uses of lasers for investigating physical phenomena are studied. The active projects included the development of a tunable, narrowband XUV light source and its application to the spectroscopy of core excited atomic states, and the development of a technique for picosecond time resolution spectroscopy of fast photophysical processes.

  9. The Geoscience Laser Altimeter System Laser Transmitter

    NASA Technical Reports Server (NTRS)

    Afzal, R. S.; Dallas, J. L.; Yu, A. W.; Mamakos, W. A.; Lukemire, A.; Schroeder, B.; Malak, A.

    2000-01-01

    The Geoscience Laser Altimeter System (GLAS), scheduled to launch in 2001, is a laser altimeter and lidar for tile Earth Observing System's (EOS) ICESat mission. The laser transmitter requirements, design and qualification test results for this space- based remote sensing instrument are presented.

  10. Laser Spectroscopy

    NASA Astrophysics Data System (ADS)

    Katori, H.; Yoneda, H.; Nakagawa, K.; Shimizu, F.

    2010-02-01

    .] -- Ultracold Ytterbium atoms in optical lattices / S. Sugawa ... [et al.] -- Ultracold polar molecules in the rovibrational ground state / J. Deiglmayr ... [et al.] -- Polar molecules near quantum degeneracy / J. Ye and D. S. Jin -- Production of a quantum gas of rovibronic ground-state molecules in an optical lattice / J. G. Danzl ... [et al.] -- Recent progress in x-ray nonlinear optics / K. Tamasaku, K. Sawada, and T. Ishikawa -- Gas in scattering media absorption spectroscopy - laser spectroscopy in unconventional environments / S. Svanberg -- Laser spectroscopy on relativistic ion beams / S. Reinhardt ... [et al.] -- Single frequency microcavity lasers and applications / L. Xu ... [et al.].

  11. Laser Wire Stripper

    NASA Technical Reports Server (NTRS)

    1983-01-01

    NASA-developed space shuttle technology is used in a laser wire stripper designed by Raytheon Company. Laser beams cut through insulation on a wire without damaging conductive metal, because laser radiation that melts plastic insulation is reflected by the metal. The laser process is fast, clean, precise and repeatable. It eliminates quality control problems and the expense of rejected wiring.

  12. Reverse laser drilling

    NASA Technical Reports Server (NTRS)

    Anthony, Thomas R. (Inventor)

    1984-01-01

    This invention provides a method for laser drilling small diameter, closely-spaced, and accurately located holes in a body of material which is transparent or substantially transparent to the laser radiation employed whereby the holes are drilled through the thickness of the body from the surface opposite to that on which the laser beam impinges to the surface of laser beam impingement.

  13. Longitudinal discharge laser baffles

    DOEpatents

    Warner, B.E.; Ault, E.R.

    1994-06-07

    The IR baffles placed between the window and the electrode of a longitudinal discharge laser improve laser performance by intercepting off-axis IR radiation from the laser and in doing so reduce window heating and subsequent optical distortion of the laser beam. 1 fig.

  14. Longitudinal discharge laser baffles

    DOEpatents

    Warner, Bruce E.; Ault, Earl R.

    1994-01-01

    The IR baffles placed between the window and the electrode of a longitudinal discharge laser improve laser performance by intercepting off-axis IR radiation from the laser and in doing so reduce window heating and subsequent optical distortion of the laser beam.

  15. Obstacles to Laser Safety

    SciTech Connect

    Barat, K

    2005-04-25

    The growth of laser development & technology has been remarkable. Unfortunately, a number of traps or obstacles to laser safety have also developed with that growth. The goal of this article is to highlight those traps, in the hope that an aware laser user will avoid them. These traps have been the cause or contributing factor of many a preventable laser accident.

  16. Narrow gap laser welding

    DOEpatents

    Milewski, J.O.; Sklar, E.

    1998-06-02

    A laser welding process including: (a) using optical ray tracing to make a model of a laser beam and the geometry of a joint to be welded; (b) adjusting variables in the model to choose variables for use in making a laser weld; and (c) laser welding the joint to be welded using the chosen variables. 34 figs.

  17. Narrow gap laser welding

    DOEpatents

    Milewski, John O.; Sklar, Edward

    1998-01-01

    A laser welding process including: (a) using optical ray tracing to make a model of a laser beam and the geometry of a joint to be welded; (b) adjusting variables in the model to choose variables for use in making a laser weld; and (c) laser welding the joint to be welded using the chosen variables.

  18. Short wavelength laser

    DOEpatents

    Hagelstein, P.L.

    1984-06-25

    A short wavelength laser is provided that is driven by conventional-laser pulses. A multiplicity of panels, mounted on substrates, are supported in two separated and alternately staggered facing and parallel arrays disposed along an approximately linear path. When the panels are illuminated by the conventional-laser pulses, single pass EUV or soft x-ray laser pulses are produced.

  19. Laser surgery - skin

    MedlinePlus

    A laser is a light beam that can be focused on a very small area. The laser heats cells in the area being ... burst." There are several types of lasers. Each laser has specific uses. The color of the light beam used is directly related to the type of ...

  20. Fiber-delivered mid-infrared (6-7) laser ablation of retinal tissue under perfluorodecalin

    NASA Astrophysics Data System (ADS)

    Mackanos, Mark A.; Joos, Karen M.; Jansen, E. Duco

    2003-07-01

    The Er:YAG laser (l=2.94mm) is an effective tool in vitreo-retinal surgery. Pulsed mid-infrared (l=6.45 mm) radiation from the Free Electron Laser has been touted as a potentially superior cutting tool. To date, use of this laser has been limited to applications in an air environment. The goal of this study was: 1) determine feasibility of fiberoptic delivery of 6.45mm using silverhalide fibers (d=700mm); 2) use infrared transparent vitreous substitute (perfluorodecalin) to allow non-contact ablation of the retina at 6.45mm. Fiber damage threshold=7.8J/cm2 (0.54GW/cm2) while transmission loss=0.54dB/m, allowing supra-ablative radiant exposures to the target. FTIR measurements of perfluorodecalin at 6.45mm yielded ma=3mm-1. Pump-probe imaging of ablation of a tissue-phantom through perfluorodecalin showed feasibility of non-contact ablation at l=6.45mm. Ablation of the retinal membranes of enucleated pig eyes was carried out under perfluorodecalin (5 Hz, 1.3 J/cm2). Each eye was cut along its equator to expose the retina. Vitreous was replaced by perfluorodecalin and laser radiation was delivered to the retina via the silverhalide fiber. The eye was rotated (at 2 rpm) using a stepper motor (0.9o/step) to create an ablation circle around the central axis of the retina (50% spot-to-spot overlap). Histological analysis of ablation yield and collateral damage will be presented. We have shown that using l=6.45mm delivered via silver halide fibers through perfluorodecalin allowed non-contact laser ablation. Remote structures are shielded, as the radiant exposure falls below the ablation threshold owing non-negligible absorption of perfluorodecalin at 6.45mm. This may optimize efficacy and safety of laser-based vitreoretinal surgery.

  1. New laser materials for laser diode pumping

    NASA Technical Reports Server (NTRS)

    Jenssen, H. P.

    1990-01-01

    The potential advantages of laser diode pumped solid state lasers are many with high overall efficiency being the most important. In order to realize these advantages, the solid state laser material needs to be optimized for diode laser pumping and for the particular application. In the case of the Nd laser, materials with a longer upper level radiative lifetime are desirable. This is because the laser diode is fundamentally a cw source, and to obtain high energy storage, a long integration time is necessary. Fluoride crystals are investigated as host materials for the Nd laser and also for IR laser transitions in other rare earths, such as the 2 micron Ho laser and the 3 micron Er laser. The approach is to investigate both known crystals, such as BaY2F8, as well as new crystals such as NaYF8. Emphasis is on the growth and spectroscopy of BaY2F8. These two efforts are parallel efforts. The growth effort is aimed at establishing conditions for obtaining large, high quality boules for laser samples. This requires numerous experimental growth runs; however, from these runs, samples suitable for spectroscopy become available.

  2. Laser accelerometer

    SciTech Connect

    Vescial, F.; Aronowitz, F.; Niguel, L.

    1990-04-24

    This patent describes a laser accelerometer. It comprises: an optical cavity characterizing a frame having an input axis (x), a cross axis (y) orthogonal to and co-planar with the input axis and a (z) axis passing through the intersection of the (x) and (y) axes, the (z) axis being orthogonal to the plane of the (x) and (y) axes; and (x) axis proof mass having a predetermined blanking surface; a flexible beam having a first end coupled to the (x) axis proof mass and a second end coupled to the frame, deflection of the flexible beams permitting a predetermined range of movement of the (x) proof mass on the input axis in a direction opposite to sensed acceleration of the frame; a laser light source having a mirror means within the cavity for providing a light ray coaxially aligned with the (z) axis; detector means having at least a first detector on a sensitive plane, the plane being normal to the (z) axis; bias and amplifier means coupled to the detector means for providing a bias current to the first detector and for amplifying the intensity signal; the (x) axis proof mass blanking surface being centrally positioned within and normal to the light ray null intensity region to provide increased blanking of the light ray in response to transverse movement of the mass on the input axis; control means responsive to the intensity signal for applying an (x) axis restoring force to restore the (x) axis proof mass to the central position and for providing an (x) axis output signal proportional to the restoring force.

  3. What is a Laser?

    NASA Astrophysics Data System (ADS)

    Julien, Lucile; Schwob, Catherine

    2015-10-01

    The first laser was built more than 50 years ago, inMay 1960: it was a pulsed ruby laser. It was a simple laboratory curiosity and nobody knew what its usefulness could be. Other devices were rapidly demonstrated, and the variety and number of lasers in the world increased at a huge rate. Currently, the annual laser world market is worth about 6 billion dollars. Thanks to the remarkable properties of laser light, laser applications increase steadily in the domains of industry, building, medicine, telecommunications, etc. One can find many lasers in research laboratories, and they are used more and more in our everyday life and almost everybody has already seen a laser beam. The goal of the first chapter of this book is to explain simply what a laser is, how it is built and how it operates. Firstly, let us point out the outstanding properties of the laser light.

  4. Tunable lasers- an overview

    SciTech Connect

    Guenther, B.D.; Buser, R.G.

    1982-08-01

    This overview of tunable lasers describes their applicability to spectroscopy in the ultraviolet and middle infrared ranges; to rapid on-line diagnostics by ultrashort cavity lasers; to exploration, by the free electron laser, for its wide tuning in the far infrared to submillimeter region; to remote detection, in areas such as portable pollution monitors, on-line chemical analyzers, auto exhaust analyzers, and production line controls; to photochemistry; and to other potential areas in diagnostics, communications, and medical and biological sciences. The following lasers are characterized by their tunability: solid state lasers, primarily alexandrite, with a tuning range of ca 1000 Angstroms; color center lasers; semiconductor lasers; dye lasers; gas lasers, where high-pressure CO/sub 2/ discharges are the best known example for a wide tunability range, and research is continuing in systems such as the alkali dimers; and, at wavelengths beyond 10 micrometers, the possibilities beyond Cerenkov and free electron lasers.

  5. Surgical lasers in dermatology

    NASA Astrophysics Data System (ADS)

    Szymanczyk, Jacek; Nowakowski, Wlodzimierz; Golebiowska, Aleksandra; Michalska, I.; Mindak, Marek K.

    1997-10-01

    Almost every laser for medical applications was first tried in dermatology. The efficiency of YAG, CO2, and Argon lasers on this area and their potential advantages over conventional methods were mostly evaluated by cosmetic effect of laser therapy. The indications for different laser treatment in such dermatological cases as: angiomas, telangiectasias, pigmented lesions, nevus flammeus congenitus, deep cavernous angiomas, skin neoplasms and condylomata acuminata are discussed in this paper and the results of the laser therapy are also presented.

  6. The laser in urology

    NASA Astrophysics Data System (ADS)

    Hofstetter, Alfons G.

    2002-10-01

    Laser is an acronym for a physical principle and means: Light Amplification by stimulated Emission of Radiation. This principle offers a lot of tissue/light effects caused by the parameters: power density/time and the special qualities of the laser light. Nowadays for diagnosis and therapy following lasers are used in urology: Krypton- and Dye-lasers as well as the Neodymium-YAG- (nd:YAG-), Holmium-YAG (Ho:YAG-), Diode-, Argon- and the CO2-lasers.

  7. Intracavity Raman lasers

    SciTech Connect

    Band, Y.B.; Ackerhalt, J.R.; Krasinski, J.S.; Heller, D.F.

    1989-02-01

    Experimental and theoretical studies of intracavity Raman lasers are presented. Advantages of intracavity Raman lasers, particularly for low-emission cross section and broadly tunable vibronic gain media, are described. Experimental studies of a hydrogen gas Raman laser pumped inside the cavity of an alexandrite laser are presented. A theoretical model of the dynamics of a unidirectional intracavity Raman ring laser is developed and solved analytically. This model is adapted to simulate experiments.

  8. Tunable Dual Semiconductor Laser

    NASA Technical Reports Server (NTRS)

    Mukai, Seiji; Kapon, Eli; Katz, Joseph; Margalit, Shlomo; Yariv, Amnon

    1987-01-01

    Parallel lasers interact in shared space to alter output wavelength. New device consists of two stripe lasers in aluminum gallium arsenide chip. Parallel stripes close enough so light from lower laser coupled into upper laser and vice versa. Lasers operated by low-duty-cycle current pulses. Lasing threshold of each about 100 mA. Currents controlled independently. Useful in optical communications systems employing wavelength-division multiplexing.

  9. Er:YAG laser ablation of epiretinal membranes in perfluorocarbon fluid-filled eyeballs: a preliminary report

    NASA Astrophysics Data System (ADS)

    Frenz, Martin; Ith, Michael; Weber, Heinz P.; Wesendahl, Th.; Janknecht, P.

    1998-06-01

    Purpose: The Er:YAG laser emitting radiation at a wavelength of 2.94 micrometer has been shown to produce precise tissue ablation because of the high water absorption at this wavelength. These studies evaluated the effects of the Er:YAG laser on pig retina utilizing a perfluoro-carbon/retina interphase with the goal to precisely ablate epiretinal membranes. Method: Various laser pulse energies were applied to the surface of pig retinas in perfluorocarbon filled enucleated eyes using a specially designed rotating sample holder. Free running ((tau) equals 250 microseconds) Er:YAG laser pulses were transmitted through a zirconium fluoride (ZrF4) fiber guarded by a low OH-quartz fiber at its distal tip. The tip diameters measured 400 micrometers and 1 mm. The fiber probe was elevated 1 mm above the retinal surface. The laser energy was applied in a systematic fashion while alternating energy settings and probe diameters. Radiant exposures were set to 1 J/cm2, 3 J/cm2, 5 J/cm2, and 10 J/cm2. Results: Eight of ten eyes were treated with concentric circles of 3.5 mm, 6.5 mm, and 9.5 mm radius. The remaining two eyes were treated with a hand held probe. Tissue ablation increased with radiant exposure in a linear fashion. At a radiant exposure of 1 J/cm2, tissue ablation was minimal with a maximum tissue ablation depth of 10 micrometers and minimal thermal damage to adjacent tissue. A radiant exposure of 10 J/cm2 produced an ablation depth of 30 - 50 micrometers. As the ablation was performed under perfluorcarbon fluid, used as transmitting medium, no laser- induced pressure transients have been measured. Conclusion: The Er:YAG laser in combination with perfluorocarbon fluid produced precise and homogeneous tissue ablation of the pig retina. Such precise tissue ablation needs to be achieved in order to safely ablate epiretinal membranes in close proximity to the retina surface. Further in-vivo experiments will be done to examine the functionality of the retina after laser

  10. Blue upconversion thulium laser

    SciTech Connect

    Nguyen, D.C.; Faulkner, G.E.; Weber, M.E.; Dulick, M.

    1990-01-01

    Upconversion has been an active area of research for at least two decades, mainly because of its wide ranging applications from infrared quantum counters, visible-emitting phosphors, to upconversion lasers. The upconversion lasers have recently become attractive with the advent of semiconductor laser diodes as the pump source. In an upconversion laser, the laser active ion is excited by internal upconversion of near-ir or red light via multiphoton excitation or cooperative processes and emits anti-Stokes visible light. Since the laser diode output wavelength can be composition turned to match the upconversion laser ion absorption lines, a substantial fraction of the ions can be driven into higher energy levels, thus enhancing the upconversion process. These upconversion solid-state lasers offer a potentially simple and compact source of visible coherent light with semiconductor laser diode excitation. We recently reported a novel upconversion thulium laser that emits blue light at 77 K. In this paper additional data on this 77 K upconversion laser as well as preliminary results on the room temperature upconversion laser are presented. In these demonstrations, dye lasers were used instead of diode lasers because they were more readily available than high power semiconductor laser diodes and their wavelengths could be adjusted easily. 14 refs., 5 figs., 1 tab.

  11. Investigation of laser injuries

    NASA Astrophysics Data System (ADS)

    Johnson, Thomas E.; Keeler, Natalie; Dennis, Jerome E.; Figueroa, Colin L.; Press, Howard A.; Rockwell, R. James, Jr.; Stuck, Bruce E.; Roach, William P.; Wartick, Ardith L.

    2003-06-01

    Recently a review of multiple laser injury and accident databases was initiated. Last year we reported on preliminary findings in this area. This past year the search for laser injury and accident reports was expanded, and a significant number of additional laser incidents were located. The database from the Food and Drug Administration"s Center for Devices and Radiological Health was supplemented with more up to date information and non-medical laser incidents were added. Rockwell Laser Industries database was verified to not contain duplicates from the new information, as was the Army"s Laser Accidents and Incidents Registry. Information from the Federal Aviation Administration regarding laser accidents and incidents were also included. Incidents not resulting in laser specific injuries has been tracked. This information was not included in our previous report. In this study, case reports are used to show gross trends in laser injury, accident and incident reporting. This study is still in progress, and evaluation is incomplete.

  12. Infrared laser system

    DOEpatents

    Cantrell, Cyrus D.; Carbone, Robert J.; Cooper, Ralph

    1982-01-01

    An infrared laser system and method for isotope separation may comprise a molecular gas laser oscillator to produce a laser beam at a first wavelength, Raman spin flip means for shifting the laser to a second wavelength, a molecular gas laser amplifier to amplify said second wavelength laser beam to high power, and optical means for directing the second wavelength, high power laser beam against a desired isotope for selective excitation thereof in a mixture with other isotopes. The optical means may include a medium which shifts the second wavelength high power laser beam to a third wavelength, high power laser beam at a wavelength coincidental with a corresponding vibrational state of said isotope and which is different from vibrational states of other isotopes in the gas mixture.

  13. Infrared laser system

    DOEpatents

    Cantrell, Cyrus D.; Carbone, Robert J.; Cooper, Ralph S.

    1977-01-01

    An infrared laser system and method for isotope separation may comprise a molecular gas laser oscillator to produce a laser beam at a first wavelength, Raman spin flip means for shifting the laser to a second wavelength, a molecular gas laser amplifier to amplify said second wavelength laser beam to high power, and optical means for directing the second wavelength, high power laser beam against a desired isotope for selective excitation thereof in a mixture with other isotopes. The optical means may include a medium which shifts the second wavelength high power laser beam to a third wavelength, high power laser beam at a wavelength coincidental with a corresponding vibrational state of said isotope and which is different from vibrational states of other isotopes in the gas mixture.

  14. Nanocrystal waveguide (NOW) laser

    DOEpatents

    Simpson, John T.; Simpson, Marcus L.; Withrow, Stephen P.; White, Clark W.; Jaiswal, Supriya L.

    2005-02-08

    A solid state laser includes an optical waveguide and a laser cavity including at least one subwavelength mirror disposed in or on the optical waveguide. A plurality of photoluminescent nanocrystals are disposed in the laser cavity. The reflective subwavelength mirror can be a pair of subwavelength resonant gratings (SWG), a pair of photonic crystal structures (PC), or a distributed feedback structure. In the case of a pair of mirrors, a PC which is substantially transmissive at an operating wavelength of the laser can be disposed in the laser cavity between the subwavelength mirrors to improve the mode structure, coherence and overall efficiency of the laser. A method for forming a solid state laser includes the steps of providing an optical waveguide, creating a laser cavity in the optical waveguide by disposing at least one subwavelength mirror on or in the waveguide, and positioning a plurality of photoluminescent nanocrystals in the laser cavity.

  15. Laser in dermatology.

    PubMed

    Boord, Mona

    2006-08-01

    The laser is a tool that will augment the surgical techniques available to the veterinarian. When using the laser compared with traditional surgery there are multiple procedures that can be performed with much greater ease, and some procedures that previously could not be performed. Specialty and academic practices have used lasers for photodynamic therapy, lithotripsy of urinary calculi, and percutaneous disk ablation. This article will focus on the lasers use in dermatology. It is essential that the surgeon learn the basics of laser physics, how the laser interacts with tissue and the safety issues one needs to consider during its use. On deciding to use the laser the surgical techniques chosen should always be based on considering the advantages and disadvantages the laser has to offer. The use of biomedical lasers is a "cutting edge" technique now available to our veterinary field. PMID:16933481

  16. Developments in laser trabeculoplasty.

    PubMed

    Tsang, Susanna; Cheng, Jason; Lee, Jacky W Y

    2016-01-01

    Laser trabeculoplasty has an increasing important role in the management of glaucoma as more emphasis is placed on minimally invasive therapies. In recent years, the following laser trabeculoplasty technologies have been introduced: micropulse laser trabeculoplasty, titanium-sapphire laser trabeculoplasty and pattern scanning trabeculoplasty. These lasers help to reduce the intraocular pressure (IOP) and the burden of glaucoma medical therapy. Literature findings regarding the safety and efficacy of these newer forms of laser trabeculoplasty in the treatment of open-angle glaucoma is summarised. These relatively newer procedures appear to have similar efficacy when compared with the former selective laser trabeculoplasty or argon laser trabeculoplasty. In addition, they potentially offer a more favourable safety profile with fewer complications, including postlaser inflammation and IOP spikes. Further large-scale studies are necessary to evaluate the long-term benefits of these newer forms of laser trabeculoplasty. Their initial promising results offer patients with glaucoma additional treatment alternatives. PMID:26377417

  17. Quantum well lasers

    SciTech Connect

    Zory, P.S. Jr.

    1993-01-01

    The semiconductor quantum well (QW) laser structure is rapidly becoming the preferred design in many applications because of its low threshold, design flexibility, and high reliability. The book begins with a brief, interesting foreword by C.H. Henry on the history of the QW laser concept and its early development. Following this introduction is a 79-page chapter by S.W. Corzine et al. on optical gain in III-V bulk and QW lasers. The next chapter on intraband relaxation and line broadening effects by M. Asada is an excellent expanded review of a topic introduced by Corzine. The remaining chapters describe multiple QW lasers, low-threshold QW laser, special aspects of AlGaAs and (short-wavelength) InGaAsP lasers, valence-band engineering, strained-layer QW lasers, AlGaInP QW lasers, and quantum wire lasers. These chapters are well written by recognized experts in the field.

  18. Laser Surveying

    NASA Technical Reports Server (NTRS)

    1978-01-01

    NASA technology has produced a laser-aided system for surveying land boundaries in difficult terrain. It does the job more accurately than conventional methods, takes only one-third the time normally required, and is considerably less expensive. In surveying to mark property boundaries, the objective is to establish an accurate heading between two "corner" points. This is conventionally accomplished by erecting a "range pole" at one point and sighting it from the other point through an instrument called a theodolite. But how do you take a heading between two points which are not visible to each other, for instance, when tall trees, hills or other obstacles obstruct the line of sight? That was the problem confronting the U.S. Department of Agriculture's Forest Service. The Forest Service manages 187 million acres of land in 44 states and Puerto Rico. Unfortunately, National Forest System lands are not contiguous but intermingled in complex patterns with privately-owned land. In recent years much of the private land has been undergoing development for purposes ranging from timber harvesting to vacation resorts. There is a need for precise boundary definition so that both private owners and the Forest Service can manage their properties with confidence that they are not trespassing on the other's land.

  19. Alexandrite laser pumped by semiconductor lasers

    SciTech Connect

    Scheps, R.; Gately, B.M.; Myers, J.F. ); Krasinski, J.S. ); Heller, D.F. )

    1990-06-04

    We report the first operation of a direct diode-pumped tunable chromium-doped solid-state laser. A small alexandrite (Cr:BeAl{sub 2}O{sub 4}) crystal was longitudinally pumped by two visible laser diodes. The threshold pump power was 12 mW using the {ital R}{sub 1} line at 680.4 nm for the pump transition, and the slope efficiency was 25%. The measured laser output bandwidth was 2.1 nm.

  20. Laser Safety Device

    NASA Technical Reports Server (NTRS)

    1992-01-01

    A major focus of work done at Air Products and Chemicals' Laser Application Laboratory is on use of ultraviolet radiation using high energy excimer lasers. Because light within the wavelength of excimer lasers is invisible, it can cause serious damage to eyes and tissue. To contain the laser beam, Air Products Incorporated a Jet Propulsion Laboratory invention described in a technical support package into its beam stops. The technology interrupts the laser pathway and allows workers to remain in the target area without shutting off the laser.

  1. Laser ablation of blepharopigmentation

    SciTech Connect

    Tanenbaum, M.; Karas, S.; McCord, C.D. Jr. )

    1988-01-01

    This article discusses laser ablation of blepharopigmentation in four stages: first, experimentally, where pigment vaporization is readily achieved with the argon blue-green laser; second, in the rabbit animal model, where eyelid blepharopigmentation markings are ablated with the laser; third, in human subjects, where the argon blue-green laser is effective in the ablation of implanted eyelid pigment; and fourth, in a case report, where, in a patient with improper pigment placement in the eyelid, the laser is used to safely and effectively ablate the undesired pigment markings. This article describes in detail the new technique of laser ablation of blepharopigmentation. Potential complications associated with the technique are discussed.

  2. Tunable chromium lasers

    SciTech Connect

    Chase, L.L.; Payne, S.A.

    1989-01-01

    During the decade that has passed since the discovery of the alexandrite laser, many other tunable vibronic sideband lasers based on Cr/sup 3 +/ have been developed. These lasers span the wavelength range from 700 nm to at least 1235 nm. Experimental and theoretical research has provided an understanding of the important factors that influence the performance of these Cr/sup 3 +/ lasers and other solid state vibronic lasers. The intrinsic performance levels of some of the most promising Cr/sup 3 +/ lasers are evaluated from extrapolated slope efficiency measurements. 7 refs., 4 figs., 2 tabs.

  3. Lasers in aviation

    NASA Astrophysics Data System (ADS)

    Goncharov, I. N.; Dezhin, V. N.; Kutakhov, V. P.; Petukhov, A. V.; Sidorin, V. M.; Sukhar, I. M.

    The way in which lasers are being incorporated into the military aircraft of the United States and the countries of Western Europe is discussed. Descriptions are given of laser weapons-guiding systems (including ranger finders and systems for target illumination), laser systems for navigation and flight-safety assurance (gyroscopes, velocity gauges, altimeters, systems providing meteorological data, proximity warning systems), and laser systems for air reconnaissance, communications, and control. Attention is also given to the Glissada laser guide path system, developed in the USSR. The physics of the systems is emphasized in the description and the principles underlying the operation of a laser are discussed in the introduction.

  4. Laser peening of metals- enabling laser technology

    SciTech Connect

    Dane, C.B.; Hackel, L.A.; Daly, J.; Harrisson, J.

    1997-11-13

    Laser peening, a surface treatment for metals, employs laser induced shocks to create deep and intense residual stresses in critical components. In many applications this technology is proving to be superior to conventional treatments such as shot peening. The laser peening process has generated sufficiently impressive results to move it from a laboratory demonstration phase into a significant industrial process. However until now this evolution has been slowed because a laser system meeting the average power requirements for a high throughput process has been lacking.

  5. Laser Wakefield Acceleration Experiments Using HERCULES Laser

    SciTech Connect

    Matsuoka, T.; McGuffey, C.; Dollar, F.; Bulanov, S. S.; Chvykov, V.; Kalintchenko, G.; Rousseau, P.; Yanovsky, V.; Maksimchuk, A.; Krushelnick, K.; Horovitz, Y.

    2009-07-25

    Laser wakefield acceleration (LWFA) in a supersonic gas-jet using a self-guided laser pulse was studied by changing laser power and plasma electron density. The recently upgraded HERCULES laser facility equipped with wavefront correction enables a peak intensity of 6.1x10{sup 19} W/cm{sup 2} at laser power of 80 TW to be delivered to the gas-jet using F/10 focusing optics. We found that electron beam charge was increased significantly with an increase of laser power from 30 TW to 80 TW and showed density threshold behavior at a fixed laser power. We also studied the influence of laser focusing conditions by changing the f-number of the optics to F/15 and found an increase in density threshold for electron production compared to the F/10 configuration. The analysis of different phenomena such as betatron motion of electrons, side scattering of the laser pulse for different focusing conditions, the influence of plasma density down ramp on LWFA are shown.

  6. Geodynamic laser ranging system laser transmitter

    NASA Technical Reports Server (NTRS)

    Dallas, J. L.; Czechanski, J. P.; Coyle, D. B.; Zukowski, B. J.; Seery, B. D.

    1991-01-01

    A description is given of the requirements and design options in the development of a spaceborne laser transmitter for NASA's Geodynamic Laser Ranging System. Three different oscillators are considered. The first is an injection-seeded ring oscillator yielding 1 mJ of energy within a 120-ps pulse. The second is a frequency-modulated mode-locked oscillator emitting 0.30 nJ in a 20-ps pulse. The third is a self-starting, additive pulse mode-locked laser. Detailed design considerations and preliminary results of these lasers are reported as well as the design of a unique multipass amplifier.

  7. Laser amplifier and method

    DOEpatents

    Backus, S.; Kapteyn, H.C.; Murnane, M.M.

    1997-07-01

    Laser amplifiers and methods for amplifying a laser beam are disclosed. A representative embodiment of the amplifier comprises first and second curved mirrors, a gain medium, a third mirror, and a mask. The gain medium is situated between the first and second curved mirrors at the focal point of each curved mirror. The first curved mirror directs and focuses a laser beam to pass through the gain medium to the second curved mirror which reflects and recollimates the laser beam. The gain medium amplifies and shapes the laser beam as the laser beam passes therethrough. The third mirror reflects the laser beam, reflected from the second curved mirror, so that the laser beam bypasses the gain medium and return to the first curved mirror, thereby completing a cycle of a ring traversed by the laser beam. The mask defines at least one beam-clipping aperture through which the laser beam passes during a cycle. The gain medium is pumped, preferably using a suitable pumping laser. The laser amplifier can be used to increase the energy of continuous-wave or, especially, pulsed laser beams including pulses of femtosecond duration and relatively high pulse rate. 7 figs.

  8. Laser amplifier and method

    DOEpatents

    Backus, Sterling; Kapteyn, Henry C.; Murnane, Margaret M.

    1997-01-01

    Laser amplifiers and methods for amplifying a laser beam are disclosed. A representative embodiment of the amplifier comprises first and second curved mirrors, a gain medium, a third mirror, and a mask. The gain medium is situated between the first and second curved mirrors at the focal point of each curved mirror. The first curved mirror directs and focuses a laser beam to pass through the gain medium to the second curved mirror which reflects and recollimates the laser beam. The gain medium amplifies and shapes the laser beam as the laser beam passes therethough. The third mirror reflects the laser beam, reflected from the second curved mirror, so that the laser beam bypasses the gain medium and return to the first curved mirror, thereby completing a cycle of a ring traversed by the laser beam. The mask defines at least one beam-clipping aperture through which the laser beam passes during a cycle. The gain medium is pumped, preferably using a suitable pumping laser. The laser amplifier can be used to increase the energy of continuous-wave or, especially, pulsed laser beams including pulses of femtosecond duration and relatively high pulse rate.

  9. Phased laser array for generating a powerful laser beam

    DOEpatents

    Holzrichter, John F.; Ruggiero, Anthony J.

    2004-02-17

    A first injection laser signal and a first part of a reference laser beam are injected into a first laser element. At least one additional injection laser signal and at least one additional part of a reference laser beam are injected into at least one additional laser element. The first part of a reference laser beam and the at least one additional part of a reference laser beam are amplified and phase conjugated producing a first amplified output laser beam emanating from the first laser element and an additional amplified output laser beam emanating from the at least one additional laser element. The first amplified output laser beam and the additional amplified output laser beam are combined into a powerful laser beam.

  10. Laser device and method

    SciTech Connect

    Myers, J. D.

    1985-06-25

    A simplified, relatively inexpensive laser device, wherein the laser elements are fixed in a body exoskeleton of electrical insulating material having a low coefficient of thermal expansion. The preferred embodiment includes a shotgun type laser filter having parallel bores which receive the laser flashlamp and laser rod in fixed relation in a body chamber. The reflector surrounds the laser filter and retains the filter within the body chamber. In the preferred method of this invention, several controlled lasing pulses are generated with each illumination pulse of the flashlamp, substantially increasing the efficiency of the laser device. The number of pulses is generally controlled by increasing the voltage to the flashlamp. The rapid multiple lasing pulses generate an elongated plasma in a fluid medium, such as the vitreous fluid body of an eye which makes the laser device extemely efficient for treating glaucoma and other medical treatments.

  11. Laser programs highlights 1993

    SciTech Connect

    1995-06-01

    Over the last two decades, the scope of our laser research has grown immensely. The small, low-power laser systems of our early days have given way to laser systems of record-breaking size and power. Now we are focusing our activities within the target physics and laser science programs to support the ignition and gain goals of the proposed glass-laser National Ignition Facility. In our laser isotope separation work, we completed the most important set of experiments in the history of the AVLIS Program in 1993, which culminated in a spectacularly successful run that met or exceeded all our objectives. We are also developing lasers and laser-related technologies for a variety of energy, commercial, and defense uses. On the horizon are transfers of important technologies for waste treatment, x-ray lithography, communications and security, optical imaging, and remote sensing, among others.

  12. Transmyocardial Laser Revascularization

    MedlinePlus

    ... Vascular Access for Hemodialysis Ventricular Assist Devices Transmyocardial Laser Revascularization Like every other organ or tissue in ... bypass surgery, there is a procedure called transmyocardial laser revascularization, also called TMLR or TMR. TMLR cannot ...

  13. Direct nuclear pumped laser

    DOEpatents

    Miley, George H.; Wells, William E.; DeYoung, Russell J.

    1978-01-01

    There is provided a direct nuclear pumped gas laser in which the lasing mechanism is collisional radiated recombination of ions. The gas laser active medium is a mixture of the gases, with one example being neon and nitrogen.

  14. Laser Acne Treatment

    MedlinePlus

    ... rashes clinical tools newsletter | contact Share | Acne Treatment, Laser A A A BEFORE: This patient wanted laster ... A popular approach is to combine an infrared laser with skin cooling to target oil gland production, ...

  15. LASIK - Laser Eye Surgery

    MedlinePlus

    ... Uveitis Focus On Pediatric Ophthalmology Education Center Oculofacial Plastic Surgery Center Laser Surgery Education Center Redmond Ethics ... Uveitis Focus On Pediatric Ophthalmology Education Center Oculofacial Plastic Surgery Center Laser Surgery Education Center Redmond Ethics ...

  16. Laser surgery - skin

    MedlinePlus

    Surgery using a laser ... used is directly related to the type of surgery being performed and the color of the tissue ... Laser surgery can be used to: Close small blood vessels to reduce blood loss Remove warts , moles , sunspots, and ...

  17. Laser particle sorter

    DOEpatents

    Martin, John C.; Buican, Tudor N.

    1989-01-01

    Method and apparatus for sorting particles, such as biological particles. A first laser defines an optical path having an intensity gradient which is effective to propel the particles along the path but which is sufficiently weak that the particles are not trapped in an axial direction. A probe laser beam interrogates the particles to identify predetermined phenotypical characteristics of the particles. A second laser beam intersects the driving first laser beam, wherein the second laser beam is activated by an output signal indicative of a predetermined characteristic. The second laser beam is switchable between a first intensity and a second intensity, where the first intensity is effective to displace selected particles from the driving laser beam and the second intensity is effective to propel selected particles along the deflection laser beam. The selected particles may then be propelled by the deflection beam to a location effective for further analysis.

  18. Laser particle sorter

    DOEpatents

    Martin, J.C.; Buican, T.N.

    1987-11-30

    Method and apparatus are provided for sorting particles, such as biological particles. A first laser is used to define an optical path having an intensity gradient which is effective to propel the particles along the path but which is sufficiently weak that the particles are not trapped in an axial direction. A probe laser beam is provided for interrogating the particles to identify predetermined phenotypical characteristics of the particles. A second laser beam is provided to intersect the driving first laser beam, wherein the second laser beam is activated by an output signal indicative of a predetermined characteristic. The second laser beam is switchable between a first intensity and a second intensity, where the first intensity is effective to displace selected particles from the driving laser beam and the second intensity is effective to propel selected particles along the deflection laser beam. The selected particles may then be propelled by the deflection beam to a location effective for further analysis. 2 figs.

  19. Laser therapy (image)

    MedlinePlus

    ... is used for many medical purposes. Because the laser beam is so small and precise, it enables physicians to safely treat specific tissue without injuring surrounding tissue. Some uses of the laser are retinal surgery, excision of lesions, and cauterization ...

  20. Laser therapy for cancer

    MedlinePlus

    Laser therapy uses a very narrow, focused beam of light to shrink or destroy cancer cells. It can ... to cut out tumors without damaging other tissue. Laser therapy is often given through a thin, lighted tube ...

  1. MESSENGER Laser Altimeter

    NASA Video Gallery

    MESSENGER's Mercury Laser Altimeter sends out laser pulses that hit the ground and return to the instrument. The amount of light that returns for each pulse gives the reflectance at that point on t...

  2. Laser Radar Animation

    NASA Video Gallery

    Laser and radar instruments aboard NASA aircraft provide measurements of the snow and ice surface and down to the bedrock under the ice. Lasers, with a shorter wavelength, measure the surface eleva...

  3. Laser hair removal.

    PubMed

    Wanner, Molly

    2005-01-01

    Since 1996, there have been numerous advances in hair laser removal that utilize melanin as a chromophore. All of the devices on the market may be used in patients with light skin (phototypes I-III) and yield hair reduction near 75%. The ruby (694 nm) laser, alexandrite (755 nm) laser, and diode (810 nm) laser, as well as intense pulsed light are commonly used devices for hair laser removal. The long-pulsed Nd:YAG (1064 nm) laser represents the safest device for hair removal in dark-skinned patients because of its long wavelength, although the diode laser, alexandrite laser, and intense pulse light may be used. For treatment of light hair, combination radiofrequency and optical devices as well as photodynamic therapy are under investigation. PMID:16229722

  4. Slender tip laser scalpel

    DOEpatents

    Veligdan, James T.

    2004-01-06

    A laser scalpel includes a ribbon optical waveguide extending therethrough and terminating at a slender optical cutting tip. A laser beam is emitted along the height of the cutting tip for cutting tissue therealong.

  5. Optics and lasers

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Report describes twenty-seven optical concepts developed for holographic viewing, spectral transmission, and film camera technology. Articles include developments in laser-Doppler systems, laser beam deflection controls, X-ray photography, and camera components.

  6. Carbon dioxide slab laser

    SciTech Connect

    Tulip, J.

    1988-01-12

    A gas slab laser is described comprising: first and second elongated electrodes each including a planar light reflecting surface disposed so as to form a light guide only in a plane perpendicular to the planar surface and to define a gas discharge gap therebetween; a laser gas disposed in the gap; and means for applying a radio frequency current between the first and second electrodes to establish a laser-exciting discharge in the laser gas.

  7. Short wavelength laser

    DOEpatents

    Hagelstein, Peter L.

    1986-01-01

    A short wavelength laser (28) is provided that is driven by conventional-laser pulses (30, 31). A multiplicity of panels (32), mounted on substrates (34), are supported in two separated and alternately staggered facing and parallel arrays disposed along an approximately linear path (42). When the panels (32) are illuminated by the conventional-laser pulses (30, 31), single pass EUV or soft x-ray laser pulses (44, 46) are produced.

  8. CO2 laser modeling

    NASA Technical Reports Server (NTRS)

    Johnson, Barry

    1992-01-01

    The topics covered include the following: (1) CO2 laser kinetics modeling; (2) gas lifetimes in pulsed CO2 lasers; (3) frequency chirp and laser pulse spectral analysis; (4) LAWS A' Design Study; and (5) discharge circuit components for LAWS. The appendices include LAWS Memos, computer modeling of pulsed CO2 lasers for lidar applications, discharge circuit considerations for pulsed CO2 lidars, and presentation made at the Code RC Review.

  9. Tunable high pressure lasers

    NASA Technical Reports Server (NTRS)

    Hess, R. V.

    1976-01-01

    Atmospheric transmission of high energy CO2 lasers is considerably improved by high pressure operation which, due to pressure broadening, permits tuning the laser lines off atmospheric absorption lines. Pronounced improvement is shown for horizontal transmission at altitudes above several kilometers and for vertical transmission through the entire atmosphere. Applications of tunable high pressure CO2 lasers to energy transmission and to remote sensing are discussed along with initial efforts in tuning high pressure CO2 lasers.

  10. Alkali-vapor lasers

    NASA Astrophysics Data System (ADS)

    Zweiback, J.; Komashko, A.; Krupke, W. F.

    2010-02-01

    We report on the results from several of our alkali laser systems. We show highly efficient performance from an alexandrite-pumped rubidium laser. Using a laser diode stack as a pump source, we demonstrate up to 145 W of average power from a CW system. We present a design for a transversely pumped demonstration system that will show all of the required laser physics for a high power system.

  11. Tunable semiconductor lasers

    NASA Technical Reports Server (NTRS)

    Taghavi-Larigani, Shervin (Inventor); Vanzyl, Jakob J. (Inventor); Yariv, Amnon (Inventor)

    2006-01-01

    Tunable semiconductor lasers are disclosed requiring minimized coupling regions. Multiple laser embodiments employ ring resonators or ring resonator pairs using only a single coupling region with the gain medium are detailed. Tuning can be performed by changing the phase of the coupling coefficient between the gain medium and a ring resonator of the laser. Another embodiment provides a tunable laser including two Mach-Zehnder interferometers in series and a reflector coupled to a gain medium.

  12. Laser cutting system

    SciTech Connect

    Dougherty, Thomas J

    2015-03-03

    A workpiece cutting apparatus includes a laser source, a first suction system, and a first finger configured to guide a workpiece as it moves past the laser source. The first finger includes a first end provided adjacent a point where a laser from the laser source cuts the workpiece, and the first end of the first finger includes an aperture in fluid communication with the first suction system.

  13. Single mode cavity laser

    SciTech Connect

    Martin, D.W.; Levy, J.L.

    1984-01-17

    This external cavity laser utilizes an unstable resonator in conjuction with a high reflectivity stripe end mirror which is oriented substantially parallel to the plane of the maximum divergence of the laser diode output beam and whose axis is substantially parallel to the plane of the junction of the laser diode. This configuration operates with high efficiency to select only the fundamental mode of the laser diode with a minimal divergence in the output beam.

  14. Excimer Lasers In Medicine

    NASA Astrophysics Data System (ADS)

    Tittel, Frank K.; Saidi, Iyad S.; Pettit, George H.; Wisoff, P. J.; Sauerbrey, Roland A.

    1989-06-01

    Excimer lasers emit light energy, short optical pulses at ultraviolet wavelengths, that results in a unique laser tissue interaction. This has led to an increasing number of studies into medical applications of these lasers in fields such as ophthalmology, urology, cardiology and neurology.

  15. Laser Programs Highlights 1998

    SciTech Connect

    Lowdermilk, H.; Cassady, C.

    1999-12-01

    This report covers the following topics: Commentary; Laser Programs; Inertial Confinement Fusion/National Ignition Facility (ICF/NIF); Atomic Vapor Laser Isotope Separation (AVLIS); Laser Science and Technology (LS&T); Information Science and Technology Program (IS&T); Strategic Materials Applications Program (SMAP); Medical Technology Program (MTP) and Awards.

  16. Carbon Dioxide Laser Guidelines

    PubMed Central

    Krupa Shankar, DS; Chakravarthi, M; Shilpakar, Rachana

    2009-01-01

    The carbon dioxide (CO2) laser is a versatile tool that has applications in ablative lasing and caters to the needs of routine dermatological practice as well as the aesthetic, cosmetic and rejuvenation segments. This article details the basics of the laser physics as applicable to the CO2 laser and offers guidelines for use in many of the above indications. PMID:20808594

  17. Laser Detection of Pollution.

    ERIC Educational Resources Information Center

    Patel, C. K. N.

    1978-01-01

    Discusses the use of laser spectroscopy in determining the presence of specific gaseous constituents. Three of currently used modes for laser detection of pollution are reviewed; (1) long-path measurements; (2) laser raman (differential absorption) measurements; and (3) optoacoustic detection. (HM)

  18. Carbon dioxide laser guidelines.

    PubMed

    Krupa Shankar, Ds; Chakravarthi, M; Shilpakar, Rachana

    2009-07-01

    The carbon dioxide (CO(2)) laser is a versatile tool that has applications in ablative lasing and caters to the needs of routine dermatological practice as well as the aesthetic, cosmetic and rejuvenation segments. This article details the basics of the laser physics as applicable to the CO(2) laser and offers guidelines for use in many of the above indications. PMID:20808594

  19. Laser bottom hole assembly

    DOEpatents

    Underwood, Lance D; Norton, Ryan J; McKay, Ryan P; Mesnard, David R; Fraze, Jason D; Zediker, Mark S; Faircloth, Brian O

    2014-01-14

    There is provided for laser bottom hole assembly for providing a high power laser beam having greater than 5 kW of power for a laser mechanical drilling process to advance a borehole. This assembly utilizes a reverse Moineau motor type power section and provides a self-regulating system that addresses fluid flows relating to motive force, cooling and removal of cuttings.

  20. Optically biased laser gyro

    SciTech Connect

    Anderson, D.Z.; Chow, W.W.; Scully, M.O.; Sanders, V.E.

    1980-10-01

    We describe a four-mode ring laser that exhibits none of the mode-locking characteristics that plague laser gyros. This laser is characterized by a bias that changes sign with a change in the direction of rotation and prevents the counterpropagating modes from locking. A theoretical analysis explaining the experimental results is outlined.

  1. Laser power transmission

    NASA Technical Reports Server (NTRS)

    Conway, Edmund J.

    1992-01-01

    An overview of previous studies related to laser power transmission is presented. Particular attention is given to the use of solar pumped lasers for space power applications. Three general laser mechanisms are addressed: photodissociation lasing driven by sunlight, photoexcitation lasing driven directly by sunlight, and photoexcitation lasing driven by thermal radiation.

  2. Laser Fundamentals and Experiments.

    ERIC Educational Resources Information Center

    Van Pelt, W. F.; And Others

    As a result of work performed at the Southwestern Radiological Health Laboratory with respect to lasers, this manual was prepared in response to the increasing use of lasers in high schools and colleges. It is directed primarily toward the high school instructor who may use the text for a short course in laser fundamentals. The definition of the…

  3. Strontium aluminum fluoride laser

    SciTech Connect

    Jenssen, H.P.

    1986-07-08

    A laser is described which consists of: a resonant cavity having a means for outputting coherent radiation and a laser medium comprising a crystal of SrAlF/sub 5/:Cr/sup 3 +/, and pump means for exciting the laser medium.

  4. Solar pumped laser

    NASA Technical Reports Server (NTRS)

    Lee, J. H.; Hohl, F.; Weaver, W. R. (Inventor)

    1984-01-01

    A solar pumped laser is described in which the lasant is a gas that will photodissociate and lase when subjected to sunrays. Sunrays are collected and directed onto the gas lasant to cause it to lase. Applications to laser propulsion and laser power transmission are discussed.

  5. Laser material processing system

    DOEpatents

    Dantus, Marcos

    2015-04-28

    A laser material processing system and method are provided. A further aspect of the present invention employs a laser for micromachining. In another aspect of the present invention, the system uses a hollow waveguide. In another aspect of the present invention, a laser beam pulse is given broad bandwidth for workpiece modification.

  6. Laser processing of plastics

    NASA Astrophysics Data System (ADS)

    Atanasov, Peter A.

    1995-03-01

    CO2-laser processing of plastics has been studied experimentally and theoretically. Welding of cylindrical parts made from polycarbonate and polypropylene, cutting of polymethyl-methacrylate plates, and drilling holes in polypropylene are presented as examples. A good coincidence between theoretical and experimental results in case of laser welding has been found. Some practical aspects of laser processing of plastics has been given.

  7. Polarization feedback laser stabilization

    DOEpatents

    Esherick, Peter; Owyoung, Adelbert

    1988-01-01

    A system for locking two Nd:YAG laser oscillators includes an optical path for feeding the output of one laser into the other with different polarizations. Elliptical polarization is incorporated into the optical path so that the change in polarization that occurs when the frequencies coincide may be detected to provide a feedback signal to control one laser relative to the other.

  8. LaserFest Celebration

    SciTech Connect

    Dr. Alan Chodos; Elizabeth A. Rogan

    2011-08-25

    LaserFest was the yearlong celebration, during 2010, of the 50th anniversary of the demonstration of the first working laser. The goals of LaserFest were: to highlight the impact of the laser in its manifold commercial, industrial and medical applications, and as a tool for ongoing scientific research; to use the laser as one example that illustrates, more generally, the route from scientific innovation to technological application; to use the laser as a vehicle for outreach, to stimulate interest among students and the public in aspects of physical science; to recognize and honor the pioneers who developed the laser and its many applications; to increase awareness among policymakers of the importance of R&D funding as evidenced by such technology as lasers. One way in which LaserFest sought to meet its goals was to encourage relevant activities at a local level all across the country -- and also abroad -- that would be identified with the larger purposes of the celebration and would carry the LaserFest name. Organizers were encouraged to record and advertise these events through a continually updated web-based calendar. Four projects were explicitly detailed in the proposals: 1) LaserFest on the Road; 2) Videos; 3) Educational material; and 4) Laser Days.

  9. Lasers: invention to application. Final report

    SciTech Connect

    Ausubel, J.H.; Langford, H.D.

    1987-08-01

    Contents include: The laser--still young at 25; Lasers in modern industries; Lasers in communications and information processing; Lasers in medicine; Lasers in science; Interactions between the science and technology of lasers; Glossary.

  10. Frequency discriminating laser

    SciTech Connect

    Thomas, M.D.

    1987-10-20

    A laser is described for discriminating between a higher gain transition and a lower gain transition to permit the laser to lase at the lower gain transition. It consists of: a laser cavity, including more than two mirrors each of which is highly transmissive at the frequency of the higher gain transition, one of which is partially reflective at the frequency of the lower gain transition, and all but the one of which are highly reflective at the frequency of the lower gain transition; an active laser medium disposed within the cavity; and means for pumping the active laser medium.

  11. Chalcogenide glass microsphere laser.

    PubMed

    Elliott, Gregor R; Murugan, G Senthil; Wilkinson, James S; Zervas, Michalis N; Hewak, Daniel W

    2010-12-01

    Laser action has been demonstrated in chalcogenide glass microsphere. A sub millimeter neodymium-doped gallium lanthanum sulphide glass sphere was pumped at 808 nm with a laser diode and single and multimode laser action demonstrated at wavelengths between 1075 and 1086 nm. The gallium lanthanum sulphide family of glass offer higher thermal stability compared to other chalcogenide glasses, and this, along with an optimized Q-factor for the microcavity allowed laser action to be achieved. When varying the pump power, changes in the output spectrum suggest nonlinear and/or thermal effects have a strong effect on laser action. PMID:21165022

  12. X-ray laser

    DOEpatents

    Nilsen, Joseph

    1991-01-01

    An X-ray laser (10) that lases between the K edges of carbon and oxygen, i.e. between 44 and 23 Angstroms, is provided. The laser comprises a silicon (12) and dysprosium (14) foil combination (16) that is driven by two beams (18, 20) of intense line focused (22, 24) optical laser radiation. Ground state nickel-like dysprosium ions (34) are resonantly photo-pumped to their upper X-ray laser state by line emission from hydrogen-like silicon ions (32). The novel X-ray laser should prove especially useful for the microscopy of biological specimens.

  13. Dual Wavelength Lasers

    NASA Technical Reports Server (NTRS)

    Walsh, Brian M.

    2010-01-01

    Dual wavelength lasers are discussed, covering fundamental aspects on the spectroscopy and laser dynamics of these systems. Results on Tm:Ho:Er:YAG dual wavelength laser action (Ho at 2.1 m and Er at 2.9 m) as well as Nd:YAG (1.06 and 1.3 m) are presented as examples of such dual wavelength systems. Dual wavelength lasers are not common, but there are criteria that govern their behavior. Based on experimental studies demonstrating simultaneous dual wavelength lasing, some general conclusions regarding the successful operation of multi-wavelength lasers can be made.

  14. Stabilized Zeeman split laser

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The development of a stablized Zeeman split laser for use in a polarization profilometer is discussed. A Hewlett-Packard laser was modified to stabilize the Zeeman split beat frequency thereby increasing the phase measurement accuracy from the Hewlett-Packard 3 degrees to an accuracy of .01 degrees. The addition of a two layered inductive winding converts the laser to a current controlled oscillator whose frequency is linearly related to coil current. This linear relationship between coil current and laser frequency permits phase locking the laser frequency to a stable crystal controlled reference frequency. The stability of the system is examined and the equipment operation procedures are outlined.

  15. Laser nanoablation of graphite

    NASA Astrophysics Data System (ADS)

    Frolov, V. D.; Pivovarov, P. A.; Zavedeeev, E. V.; Komlenok, M. S.; Kononenko, V. V.; Konov, V. I.

    2014-01-01

    Experimental data on laser ablation of highly oriented pyrolitic graphite by nanosecond pulsed UV ( nm) and green ( nm) lasers are presented. It was found that below graphite vaporization threshold 1 J/cm, the nanoablation regime can be realized with material removal rates as low as 10 nm/pulse. The difference between physical (vaporization) and physical-chemical (heating + oxidation) ablation regimes is discussed. Special attention is paid to the influence of laser fluence and pulse number on ablation kinetics. Possibility of laser-induced graphite surface nanostructuring has been demonstrated. Combination of tightly focused laser beam and sharp tip of scanning probe microscope was applied to improve material nanoablation.

  16. Laser assisted deposition

    NASA Technical Reports Server (NTRS)

    Dutta, S.

    1983-01-01

    Applications of laser-based processing techniques to solar cell metallization are discussed. Laser-assisted thermal or photolytic maskless deposition from organometallic vapors or solutions may provide a viable alternative to photovoltaic metallization systems currently in use. High power, defocused excimer lasers may be used in conjunction with masks as an alternative to direct laser writing to provide higher throughput. Repeated pulsing with excimer lasers may eliminate the need for secondary plating techniques for metal film buildup. A comparison between the thermal and photochemical deposition processes is made.

  17. Laser Diode Ignition (LDI)

    NASA Technical Reports Server (NTRS)

    Kass, William J.; Andrews, Larry A.; Boney, Craig M.; Chow, Weng W.; Clements, James W.; Merson, John A.; Salas, F. Jim; Williams, Randy J.; Hinkle, Lane R.

    1994-01-01

    This paper reviews the status of the Laser Diode Ignition (LDI) program at Sandia National Labs. One watt laser diodes have been characterized for use with a single explosive actuator. Extensive measurements of the effect of electrostatic discharge (ESD) pulses on the laser diode optical output have been made. Characterization of optical fiber and connectors over temperature has been done. Multiple laser diodes have been packaged to ignite multiple explosive devices and an eight element laser diode array has been recently tested by igniting eight explosive devices at predetermined 100 ms intervals.

  18. Lasers in otorhinolaryngology

    NASA Astrophysics Data System (ADS)

    Pais Clemente, Manuel P.

    1992-03-01

    Lasers are now commonly accepted and widely used surgical instruments in otorhinolaryngology. There have been a great number of technological advances with lasers that have contributed to the expansion of this new surgical modality with an increased number of medical applications. Surgical strategies have also changed and are more favorable toward conservative surgery in which less tissues is removed than with more radical resections. This combination of improving technology and medical attitudes has changed the field of otorhinolaryngology, and resulted in an expanding use of laser surgery. Since 1973 we have been using the carbon dioxide laser in the treatment of diseases of the upper aero digestive systems, learning this new surgical technique from the pioneer work of Strong, Jako, and Vaughan. It is our conviction that a laser surgeon must have a thorough knowledge of laser biophysics, instrumentation, safety protocols, and surgical indications, and have the technical skills to perform laser surgery. Laser technology continues to improve at an increased speed, and it is imperative to update knowledge of current and potential applications of lasers in our specialty. It is the purpose of this article to present our clinical experience of 18 years with the use of lasers in surgery of ORL, emphasizing the carbon dioxide laser.

  19. Laser surgery: using the carbon dioxide laser.

    PubMed Central

    Wright, V. C.

    1982-01-01

    In 1917 Einstein theorized tha through an atomic process a unique kind of electromagnetic radiation could be produced by stimulated emission. When such radiation is in the optical or infrared spectrum it is termed laser (light amplification by stimulated emission of radiation) light. A laser, a high-intensity light source, emits a nearly parallel electromagnetic beam of energy at a given wavelength that can be captured by a lens and concentrated in the focal spot. The wavelength determines how the laser will be used. The carbon dioxide laser is now successfully employed for some surgical procedures in gynecology, otorhinolaryngology, neurosurgery, and plastic and general surgery. The CO2 laser beam is directed through the viewing system of an operating microscope or through a hand-held laser component. Its basic action in tissue is thermal vaporization; it causes minimal damage to adjacent tissues. Surgeons require special training in the basic methods and techniques of laser surgery, as well as in the safety standards that must be observed. Images FIG. 5 PMID:7074503

  20. Laser radar improvements

    NASA Astrophysics Data System (ADS)

    Jelalian, A. V.

    1981-11-01

    A short history of the uses of various laser radars is presented, and appropriate applications of laser and microwave radars are discussed. CO2 laser radar, operating at 10.6 microns, is considered for use in aircraft navigation systems, fire-control systems for armored vehicle and aircraft, missile guidance, severe storm research, line-of-sight command of missiles, wind turbine site surveys, clear-air turbulence monitors for aircraft, and satellite tracking. Microwave radar is all-weather, but is subject to multipath inaccuracies, countermeasures, and angular resolution limitations, so hybrid laser microwave systems look promising for microwave target acquisition and laser tracking. Advantages and disadvantages of the use of ruby, YAG, and CO2 lasers in varying atmospheric conditions are discussed. Development of a laser radar pod for obstacle detection, Doppler navigation, automatic terrain following, hover control, weapon delivery, and precision searching is noted.

  1. Laser diode protection circuit

    SciTech Connect

    Burgyan, L.; Hand, W.L.

    1990-05-08

    This patent describes a method for protecting a laser diode included within an electro-optical circuit. It comprises: the laser diode, a DC bias supply for supplying forward conduction current to the laser diode to cause it to emit light energy at a predetermined quiescent operating point, and an RF amplifier means for supplying an RF amplitude of an analog modulating signal to the laser diode for modulating the intensity of the emitted light energy about the quiescent operating point thereof, the method including providing a very high impedance to the laser diode during its nominal operating conditions about the quiescent point and, sensing an instantaneous amplitude of the RF amplitude modulating signal to detect amplitude surges therein, and responding to the sensing means by removing forward conduction current from the laser diode during the sense amplitude surges int he RF amplitude of the analog modulating signal, thereby causing the laser diode to reduce emission of light energy to a safe level.

  2. Laser beam shaping techniques

    SciTech Connect

    DICKEY,FRED M.; WEICHMAN,LOUIS S.; SHAGAM,RICHARD N.

    2000-03-16

    Industrial, military, medical, and research and development applications of lasers frequently require a beam with a specified irradiance distribution in some plane. A common requirement is a laser profile that is uniform over some cross-section. Such applications include laser/material processing, laser material interaction studies, fiber injection systems, optical data image processing, lithography, medical applications, and military applications. Laser beam shaping techniques can be divided into three areas: apertured beams, field mappers, and multi-aperture beam integrators. An uncertainty relation exists for laser beam shaping that puts constraints on system design. In this paper the authors review the basics of laser beam shaping and present applications and limitations of various techniques.

  3. Endoscopic Gastrointestinal Laser Therapy

    PubMed Central

    Buchi, Kenneth N.

    1985-01-01

    The development of flexible fibers for the delivery of laser energy led to the first endoscopic laser applications in humans in the early 1970s. Since that time, much has been learned about applications throughout the gastrointestinal tract. The risks appear to be minimal. The coagulative effect of laser energy is used to treat gastrointestinal hemorrhage and small, benign mucosal lesions. The ablative effect of the Nd:YAG laser on tissue is used for palliative therapy for malignant gastrointestinal disorders and incisional therapy for anatomic lesions such as strictures or cysts. New laser modalities that potentially can be tuned throughout large segments of the electromagnetic spectrum, new fiber-optic delivery systems with specialized tips and new methods of sensitizing tissue to laser energy all indicate that the endoscopic laser should continue to have many new and innovative applications. ImagesFigure 1.Figure 2.Figure 3. PMID:3911589

  4. Laser Applications in Orthodontics

    PubMed Central

    Heidari, Somayeh; Torkan, Sepideh

    2013-01-01

    A laser is a collimated single wavelength of light which delivers a concentrated source of energy. Soon after different types of lasers were invented, investigators began to examine the effects of different wavelengths of laser energy on oral tissues, routine dental procedures and experimental applications. Orthodontists, along with other specialist in different fields of dentistry, can now benefit from several different advantages that lasers provide during the treatment process, from the beginning of the treatment, when separators are placed, to the time of resin residues removal from the tooth surface at the end of orthodontic treatment. This article outlines some of the most common usages of laser beam in orthodontics and also provides a comparison between laser and other conventional method that were the standard of care prior to the advent of laser in this field. PMID:25606324

  5. Laser safety in dentistry

    NASA Astrophysics Data System (ADS)

    Wigdor, Harvey A.

    1997-05-01

    One of the major causes of anxiety in the dental clinic is the dental handpiece. Because dentists wish to provide a method which can replace the drill there has often been a premature use of the laser in dentistry. Various lasers have been introduced into the clinic before research has shown the laser used is of clinical benefit. Any new treatment method must not compromise the health of the patient being treated. Thus a method of evaluating the clinical abilities of dentists and their understanding the limitations of the laser used must be developed. Dentist must be trained in the basic interaction of the laser on oral tissues. The training has to concentrate on the variation of the laser wavelength absorption in the different tissues of the oral cavity. Because of the differences in the optical properties of these tissues great care must be exercised by practitioners using lasers on patients.

  6. ORION laser target diagnostics

    SciTech Connect

    Bentley, C. D.; Edwards, R. D.; Andrew, J. E.; James, S. F.; Gardner, M. D.; Comley, A. J.; Vaughan, K.; Horsfield, C. J.; Rubery, M. S.; Rothman, S. D.; Daykin, S.; Masoero, S. J.; Palmer, J. B.; Meadowcroft, A. L.; Williams, B. M.; Gumbrell, E. T.; Fyrth, J. D.; Brown, C. R. D.; Hill, M. P.; Oades, K.; and others

    2012-10-15

    The ORION laser facility is one of the UK's premier laser facilities which became operational at AWE in 2010. Its primary mission is one of stockpile stewardship, ORION will extend the UK's experimental plasma physics capability to the high temperature, high density regime relevant to Atomic Weapons Establishment's (AWE) program. The ORION laser combines ten laser beams operating in the ns regime with two sub ps short pulse chirped pulse amplification beams. This gives the UK a unique combined long pulse/short pulse laser capability which is not only available to AWE personnel but also gives access to our international partners and visiting UK academia. The ORION laser facility is equipped with a comprehensive suite of some 45 diagnostics covering optical, particle, and x-ray diagnostics all able to image the laser target interaction point. This paper focuses on a small selection of these diagnostics.

  7. Semiconductor nanowire lasers

    NASA Astrophysics Data System (ADS)

    Eaton, Samuel W.; Fu, Anthony; Wong, Andrew B.; Ning, Cun-Zheng; Yang, Peidong

    2016-06-01

    The discovery and continued development of the laser has revolutionized both science and industry. The advent of miniaturized, semiconductor lasers has made this technology an integral part of everyday life. Exciting research continues with a new focus on nanowire lasers because of their great potential in the field of optoelectronics. In this Review, we explore the latest advancements in the development of nanowire lasers and offer our perspective on future improvements and trends. We discuss fundamental material considerations and the latest, most effective materials for nanowire lasers. A discussion of novel cavity designs and amplification methods is followed by some of the latest work on surface plasmon polariton nanowire lasers. Finally, exciting new reports of electrically pumped nanowire lasers with the potential for integrated optoelectronic applications are described.

  8. ORION laser target diagnosticsa)

    NASA Astrophysics Data System (ADS)

    Bentley, C. D.; Edwards, R. D.; Andrew, J. E.; James, S. F.; Gardner, M. D.; Comley, A. J.; Vaughan, K.; Horsfield, C. J.; Rubery, M. S.; Rothman, S. D.; Daykin, S.; Masoero, S. J.; Palmer, J. B.; Meadowcroft, A. L.; Williams, B. M.; Gumbrell, E. T.; Fyrth, J. D.; Brown, C. R. D.; Hill, M. P.; Oades, K.; Wright, M. J.; Hood, B. A.; Kemshall, P.

    2012-10-01

    The ORION laser facility is one of the UK's premier laser facilities which became operational at AWE in 2010. Its primary mission is one of stockpile stewardship, ORION will extend the UK's experimental plasma physics capability to the high temperature, high density regime relevant to Atomic Weapons Establishment's (AWE) program. The ORION laser combines ten laser beams operating in the ns regime with two sub ps short pulse chirped pulse amplification beams. This gives the UK a unique combined long pulse/short pulse laser capability which is not only available to AWE personnel but also gives access to our international partners and visiting UK academia. The ORION laser facility is equipped with a comprehensive suite of some 45 diagnostics covering optical, particle, and x-ray diagnostics all able to image the laser target interaction point. This paper focuses on a small selection of these diagnostics.

  9. ORION laser target diagnostics.

    PubMed

    Bentley, C D; Edwards, R D; Andrew, J E; James, S F; Gardner, M D; Comley, A J; Vaughan, K; Horsfield, C J; Rubery, M S; Rothman, S D; Daykin, S; Masoero, S J; Palmer, J B; Meadowcroft, A L; Williams, B M; Gumbrell, E T; Fyrth, J D; Brown, C R D; Hill, M P; Oades, K; Wright, M J; Hood, B A; Kemshall, P

    2012-10-01

    The ORION laser facility is one of the UK's premier laser facilities which became operational at AWE in 2010. Its primary mission is one of stockpile stewardship, ORION will extend the UK's experimental plasma physics capability to the high temperature, high density regime relevant to Atomic Weapons Establishment's (AWE) program. The ORION laser combines ten laser beams operating in the ns regime with two sub ps short pulse chirped pulse amplification beams. This gives the UK a unique combined long pulse/short pulse laser capability which is not only available to AWE personnel but also gives access to our international partners and visiting UK academia. The ORION laser facility is equipped with a comprehensive suite of some 45 diagnostics covering optical, particle, and x-ray diagnostics all able to image the laser target interaction point. This paper focuses on a small selection of these diagnostics. PMID:23126904

  10. Nanofabrication with Pulsed Lasers

    NASA Astrophysics Data System (ADS)

    Kabashin, A. V.; Delaporte, Ph.; Pereira, A.; Grojo, D.; Torres, R.; Sarnet, Th.; Sentis, M.

    2010-03-01

    An overview of pulsed laser-assisted methods for nanofabrication, which are currently developed in our Institute (LP3), is presented. The methods compass a variety of possibilities for material nanostructuring offered by laser-matter interactions and imply either the nanostructuring of the laser-illuminated surface itself, as in cases of direct laser ablation or laser plasma-assisted treatment of semiconductors to form light-absorbing and light-emitting nano-architectures, as well as periodic nanoarrays, or laser-assisted production of nanoclusters and their controlled growth in gaseous or liquid medium to form nanostructured films or colloidal nanoparticles. Nanomaterials synthesized by laser-assisted methods have a variety of unique properties, not reproducible by any other route, and are of importance for photovoltaics, optoelectronics, biological sensing, imaging and therapeutics.

  11. Lasers in orthodontics

    PubMed Central

    Nalcaci, Ruhi; Cokakoglu, Serpil

    2013-01-01

    Many types of dental lasers are currently available that can be efficiently used for soft and hard tissue applications in the field of orthodontics. For achieving the desired effects in the target tissue, knowledge of laser characteristics such as power, wavelength and timing, is necessary. Laser therapy is advantageous because it often avoids bleeding, can be pain free, is non-invasive and is relatively quick. The high cost is its primary disadvantage. It is very important to take the necessary precautions to prevent possible tissue damage when using laser dental systems. Here, we reviewed the main types and characteristics of laser systems used in dental practice and discuss the applications of lasers in orthodontics, harmful effects and laser system safety. PMID:24966719

  12. Lasers in space

    NASA Astrophysics Data System (ADS)

    Michaelis, M. M.; Forbes, A.; Bingham, R.; Kellett, B. J.; Mathye, A.

    2008-05-01

    A variety of laser applications in space, past, present, future and far future are reviewed together with the contributions of some of the scientists and engineers involved, especially those that happen to have South African connections. Historically, two of the earliest laser applications in space, were atmospheric LIDAR and lunar ranging. These applications involved atmospheric physicists, several astronauts and many of the staff recruited into the Soviet and North American lunar exploration programmes. There is a strong interest in South Africa in both LIDAR and lunar ranging. Shortly after the birth of the laser (and even just prior) theoretical work on photonic propulsion and space propulsion by laser ablation was initiated by Georgii Marx, Arthur Kantrowitz and Eugen Saenger. Present or near future experimental programs are developing in the following fields: laser ablation propulsion, possibly coupled with rail gun or gas gun propulsion; interplanetary laser transmission; laser altimetry; gravity wave detection by space based Michelson interferometry; the de-orbiting of space debris by high power lasers; atom laser interferometry in space. Far future applications of laser-photonic space-propulsion were also pioneered by Carl Sagan and Robert Forward. They envisaged means of putting Saenger's ideas into practice. Forward also invented a laser based method for manufacturing solid antimatter or SANTIM, well before the ongoing experiments at CERN with anti-hydrogen production and laser-trapping. SANTIM would be an ideal propellant for interstellar missions if it could be manufactured in sufficient quantities. It would be equally useful as a power source for the transmission of information over light year distances. We briefly mention military lasers. Last but not least, we address naturally occurring lasers in space and pose the question: "did the Big Bang lase?"

  13. Laser heated thermoluminescence dosimetry

    SciTech Connect

    Justus, B.L.; Huston, A.L.

    1996-06-01

    We report a novel laser-heated thermoluminescence dosimeter that is radically different from previous laser-heated dosimeters. The dosimeter is a semiconductor and metal ion doped silica glass that has excellent optical transparency. The high optical quality of the glass essentially eliminates laser power loss due to light scattering. This efficient utilization of the laser power permits operation of the dosimeter without strong absorption of the laser, as is required in traditional laser-heated dosimetry. Our laser-heated dosimeter does not rely on the diffusion of heat from a separate, highly absorbing substrate, but operates via intimate, localized heating within the glass dosimeter due to the absorption of the laser light by rare earth ion dopants in the glass. Following absorption of the laser light, the rare earth ions transfer energy to the surrounding glass via nonradiative relaxation processes, resulting in rapid, localized temperature increases sufficient to release all the filled traps near the ions. As the heat diffuses radially away from the rare earth ions the temperature plummets dramatically on a manometer distance scale and the release of additional filled traps subsides. A key distinguishing feature of this laser-heated dosimeter is the ability to read the dose information more than once. While laser-heating provides complete information about the radiation exposure experienced by the glass due to the release of locally heated traps, the process leaves the remaining filled bulk traps undisturbed. The bulk traps can be read using traditional bulk heating methods and can provide a direct determination of an accumulated dose, measured following any number of laser-heated readouts. Laser-heated dosimetry measurements have been performed using a solid state diode laser for the readout following radiation exposure with a {sup 60}Co source.

  14. Investigation of Laser Parameters in Silicon Pulsed Laser Conduction Welding

    NASA Astrophysics Data System (ADS)

    Shayganmanesh, Mahdi; Khoshnoud, Afsaneh

    2016-03-01

    In this paper, laser welding of silicon in conduction mode is investigated numerically. In this study, the effects of laser beam characteristics on the welding have been studied. In order to model the welding process, heat conduction equation is solved numerically and laser beam energy is considered as a boundary condition. Time depended heat conduction equation is used in our calculations to model pulsed laser welding. Thermo-physical and optical properties of the material are considered to be temperature dependent in our calculations. Effects of spatial and temporal laser beam parameters such as laser beam spot size, laser beam quality, laser beam polarization, laser incident angle, laser pulse energy, laser pulse width, pulse repetition frequency and welding speed on the welding characteristics are assessed. The results show that how the temperature dependent thermo-physical and optical parameters of the material are important in laser welding modeling. Also the results show how the parameters of the laser beam influence the welding characteristics.

  15. Research of the quenched dye lasers pumped by excimer lasers

    SciTech Connect

    Xue Shaolin; Lou Qihong

    1996-12-31

    In this paper, the quenched dye lasers pumped by XeCl and KrF excimer lasers were investigated theoretically and experimentally. Dye laser pulses with duration of 0.8 ns for XeCl laser pumping and 2 ns for KrF laser pumping were obtained. The dye Rhodamine 6G dissolved in methyl was used as the active medium in the quenched dye laser. When the pump laser was KrF and the active medium was Coumarin 498 the quenched dye laser emitted pulse with duration of about 2 ns. The characteristics of the quenched dye laser was also investigated in detail.

  16. Laser system using ultra-short laser pulses

    SciTech Connect

    Dantus, Marcos; Lozovoy, Vadim V.; Comstock, Matthew

    2009-10-27

    A laser system using ultrashort laser pulses is provided. In another aspect of the present invention, the system includes a laser, pulse shaper and detection device. A further aspect of the present invention employs a femtosecond laser and binary pulse shaping (BPS). Still another aspect of the present invention uses a laser beam pulse, a pulse shaper and a SHG crystal.

  17. Laser treatment in gynecology

    NASA Astrophysics Data System (ADS)

    de Riese, Cornelia

    2004-07-01

    This presentation is designed as a brief overview of laser use in gynecology, for non-medical researchers involved in development of new laser techniques. The literature of the past decade is reviewed. Differences in penetration, absorption, and suitable delivery media for the beams dictate clinical application. The use of CO2 laser in the treatment of uterine cervical intraepithelial lesions is well established and indications as well as techniques have not changed over 30 years. The Cochrane Systematic Review from 2000 suggests no obviously superior technique. CO2 laser ablation of the vagina is also established as a safe treatment modality for VAIN. CO2 laser permits treatment of lesions with excellent cosmetic and functional results. The treatment of heavy menstrual bleeding by destruction of the endometrial lining using various techniques has been the subject of a 2002 Cochran Database Review. Among the compared treatment modalities are newer and modified laser techniques. Conclusion by reviewers is that outcomes and complication profiles of newer techniques compare favorably with the gold standard of endometrial resection. The ELITT diode laser system is one of the new successful additions. CO2 laser is also the dominant laser type used with laparoscopy for ablation of endometriotic implants. Myoma coagulation or myolysis with Nd:Yag laser through the laparoscope or hysteroscope is a conservative treatment option. Even MRI guided percutaneous approaches have been described. No long-term data are available.

  18. Photobiomodulation in laser surgery

    NASA Astrophysics Data System (ADS)

    Liu, Timon Cheng-Yi; Rong, Dong-Liang; Huang, Jin; Deng, Xiao-Yuan; Liu, Song-Hao

    2006-01-01

    Laser surgery provides good exposure with clear operating fields and satisfactory preliminary functional results. In contrast to conventional excision, it was found that matrix metalloproteinases and the tissue inhibitors of metalloproteinases -1 mRNA expression is higher, myofibroblasts appeared and disappeared slower in laser excision wounds. It has been suggested that the better anatomical and functional results achieved following laser cordectomy may be explained by the fact that such procedures result in better, more rapid healing processes to recover vocal cord for early glottic tumors and better. In this paper, the role of photobiomodulation in laser surgery will be discussed by the cultured monolayer normal human skin fibroblast model of the photobiomodulation of marginal irradiation of high intensity laser beam, the photobiomodulation related to the irradiated tissue, the biological information model of photobiomodulation and the animal models of laser surgery. Although high intensity laser beam is so intense that it destroys the irradiated cells or tissue, its marginal irradiation intensity is so low that there is photobiomodulation on non-damage cells to modulate the regeneration of partly damaged tissue so that the surgery of laser of different parameters results in different post-surgical recovery. It was concluded that photobiomodulation might play an important role in the long-term effects of laser surgery, which might be used to design laser surgery.

  19. Lasers in medicine

    NASA Astrophysics Data System (ADS)

    Peng, Qian; Juzeniene, Asta; Chen, Jiyao; Svaasand, Lars O.; Warloe, Trond; Giercksky, Karl-Erik; Moan, Johan

    2008-05-01

    It is hard to imagine that a narrow, one-way, coherent, moving, amplified beam of light fired by excited atoms is powerful enough to slice through steel. In 1917, Albert Einstein speculated that under certain conditions atoms could absorb light and be stimulated to shed their borrowed energy. Charles Townes coined the term laser (light amplification by stimulated emission of radiation) in 1951. Theodore Maiman investigated the glare of a flash lamp in a rod of synthetic ruby, creating the first human-made laser in 1960. The laser involves exciting atoms and passing them through a medium such as crystal, gas or liquid. As the cascade of photon energy sweeps through the medium, bouncing off mirrors, it is reflected back and forth, and gains energy to produce a high wattage beam of light. Although lasers are today used by a large variety of professions, one of the most meaningful applications of laser technology has been through its use in medicine. Being faster and less invasive with a high precision, lasers have penetrated into most medical disciplines during the last half century including dermatology, ophthalmology, dentistry, otolaryngology, gastroenterology, urology, gynaecology, cardiology, neurosurgery and orthopaedics. In many ways the laser has revolutionized the diagnosis and treatment of a disease. As a surgical tool the laser is capable of three basic functions. When focused on a point it can cauterize deeply as it cuts, reducing the surgical trauma caused by a knife. It can vaporize the surface of a tissue. Or, through optical fibres, it can permit a doctor to see inside the body. Lasers have also become an indispensable tool in biological applications from high-resolution microscopy to subcellular nanosurgery. Indeed, medical lasers are a prime example of how the movement of an idea can truly change the medical world. This review will survey various applications of lasers in medicine including four major categories: types of lasers, laser

  20. Photonic crystal microcavity lasers and laser arrays

    NASA Astrophysics Data System (ADS)

    Cao, Jiang-Rong

    As a state-of-the-art technology, photonic crystal microcavity lasers have great potentials to resolve many semiconductor laser performance challenges, owing to their compact size, high spontaneous emission factor, and inherent advantages in dimension scalability. This thesis describes efficient numerical analyzing methods for multimode photonic crystal microcavities, including a parallel computing three-dimensional finite-difference time-domain method combined with Pade interpolation, point group projection, and vectorial Green's function method. With the help of these analyzing tools, various experimental photonic crystal microcavity devices fabricated in InGaAsP/InP based materials were studies. Room temperature optical pumped InGaAsP suspended membrane photonic crystal microcavity lasers were demonstrated. Their lithographical fine-tuning, above room temperature operations, mode identifications and polarizations were demonstrated. Room temperature continuous wave (CW) optically pumped photonic crystal microcavity lasers at diameter less than 3.2 mum were demonstrated with crystalline alpha-Al 2O3 (sapphire) as a cladding layer to the InGaAsP membrane. The far-field radiation profiles from these microcavity lasers were measured and compared with our numerical modeling predictions. Two electrical injection scenes for photonic crystal microcavity lasers were introduced, together with some preliminary results including the demonstrations of optically pumped lasing of highly doped cavities and cavities with an electrical conduction post underneath. Electrically excited photonic crystal microcavity light emitting diodes (LEDs) were also experimentally demonstrated.

  1. Laser induced biological heating analyzed

    NASA Astrophysics Data System (ADS)

    Liu, Phue

    1985-08-01

    A quantitative analysis of the vaporization of tumors by pulsed CO2 lasers, incision by CW CO2 lasers, tissue coagulation by argon lasers, thermal killing of cancerous cells by He-Ne lasers, and the application of heat by CO2 lasers is presented. Although the calculations are based on a simplified skin model, it may prove useful in clinical treatments.

  2. Laser Safety Inspection Criteria

    SciTech Connect

    Barat, K

    2005-02-11

    A responsibility of the Laser Safety Officer (LSO) is to perform laser safety audits. The American National Standard Z136.1 Safe use of Lasers references this requirement in several sections: (1) Section 1.3.2 LSO Specific Responsibilities states under Hazard Evaluation, ''The LSO shall be responsible for hazards evaluation of laser work areas''; (2) Section 1.3.2.8, Safety Features Audits, ''The LSO shall ensure that the safety features of the laser installation facilities and laser equipment are audited periodically to assure proper operation''; and (3) Appendix D, under Survey and Inspections, it states, ''the LSO will survey by inspection, as considered necessary, all areas where laser equipment is used''. Therefore, for facilities using Class 3B and or Class 4 lasers, audits for laser safety compliance are expected to be conducted. The composition, frequency and rigueur of that inspection/audit rests in the hands of the LSO. A common practice for institutions is to develop laser audit checklists or survey forms. In many institutions, a sole Laser Safety Officer (LSO) or a number of Deputy LSO's perform these audits. For that matter, there are institutions that request users to perform a self-assessment audit. Many items on the common audit list and the associated findings are subjective because they are based on the experience and interest of the LSO or auditor in particular items on the checklist. Beam block usage is an example; to one set of eyes a particular arrangement might be completely adequate, while to another the installation may be inadequate. In order to provide more consistency, the National Ignition Facility Directorate at Lawrence Livermore National Laboratory (NIF-LLNL) has established criteria for a number of items found on the typical laser safety audit form. These criteria are distributed to laser users, and they serve two broad purposes: first, it gives the user an expectation of what will be reviewed by an auditor, and second, it is an

  3. Laser plasmadynamic energy conversion

    NASA Technical Reports Server (NTRS)

    Shimada, K.

    1976-01-01

    The generation of electrons ions by interacting an intense laser beam with cesium vapor is considered. Theoretical calculation shows that the conversion efficiency is as high as 40 percent if the entire photon energy is utilized in ionizing the cesium vapor that is generated initially by the incoming laser beam. An output voltage is expected to be generated across two electrodes, one of which is the liquid cesium, by keeping the other electrode at a different work function. Evaluation of the laser plasmadynamic (LPD) converter was performed using pulsed ruby and Nd-glass lasers. Although the results obtained to date indicate an efficiency smaller than that of theoretical predictions, an unoptimized LPD converter did demonstrate the capability of converting laser energy at large power levels. The limitations in the performance may by due to converter geometry, the types of lasers used, and other limitations inherent to the cesium plasma.

  4. Laser rocket system analysis

    NASA Technical Reports Server (NTRS)

    Jones, W. S.; Forsyth, J. B.; Skratt, J. P.

    1979-01-01

    The laser rocket systems investigated in this study were for orbital transportation using space-based, ground-based and airborne laser transmitters. The propulsion unit of these systems utilizes a continuous wave (CW) laser beam focused into a thrust chamber which initiates a plasma in the hydrogen propellant, thus heating the propellant and providing thrust through a suitably designed nozzle and expansion skirt. The specific impulse is limited only by the ability to adequately cool the thruster and the amount of laser energy entering the engine. The results of the study showed that, with advanced technology, laser rocket systems with either a space- or ground-based laser transmitter could reduce the national budget allocated to space transportation by 10 to 345 billion dollars over a 10-year life cycle when compared to advanced chemical propulsion systems (LO2-LH2) of equal capability. The variation in savings depends upon the projected mission model.

  5. Laser radar in robotics

    SciTech Connect

    Carmer, D.C.; Peterson, L.M.

    1996-02-01

    In this paper the authors describe the basic operating principles of laser radar sensors and the typical algorithms used to process laser radar imagery for robotic applications. The authors review 12 laser radar sensors to illustrate the variety of systems that have been applied to robotic applications wherein information extracted from the laser radar data is used to automatically control a mechanism or process. Next, they describe selected robotic applications in seven areas: autonomous vehicle navigation, walking machine foot placement, automated service vehicles, manufacturing and inspection, automotive, military, and agriculture. They conclude with a discussion of the status of laser radar technology and suggest trends seen in the application of laser radar sensors to robotics. Many new applications are expected as the maturity level progresses and system costs are reduced.

  6. Synthetic laser medium

    DOEpatents

    Stokowski, Stanley E.

    1989-01-01

    A laser medium is particularly useful in high average power solid state lasers. The laser medium includes a chormium dopant and preferably neodymium ions as codopant, and is primarily a gadolinium scandium gallium garnet, or an analog thereof. Divalent cations inhibit spiral morphology as large boules from which the laser medium is derived are grown, and a source of ions convertible between a trivalent state and a tetravalent state at a low ionization energy are in the laser medium to reduce an absorption coefficient at about one micron wavelength otherwise caused by the divalent cations. These divalent cations and convertible ions are dispersed in the laser medium. Preferred convertible ions are provided from titanium or cerium sources.

  7. Synthetic laser medium

    DOEpatents

    Stokowski, S.E.

    1987-10-20

    A laser medium is particularly useful in high average power solid state lasers. The laser medium includes a chromium dopant and preferably neodymium ions as codopant, and is primarily a gadolinium scandium gallium garnet, or an analog thereof. Divalent cations inhibit spiral morphology as large boules from which the laser medium is derived are grown, and a source of ions convertible between a trivalent state and a tetravalent state at a low ionization energy are in the laser medium to reduce an absorption coefficient at about one micron wavelength otherwise caused by the divalent cations. These divalent cations and convertible ions are dispersed in the laser medium. Preferred convertible ions are provided from titanium or cerium sources.

  8. Laser induced nuclear reactions

    SciTech Connect

    Ledingham, Ken; McCanny, Tom; Graham, Paul; Fang Xiao; Singhal, Ravi; Magill, Joe; Creswell, Alan; Sanderson, David; Allott, Ric; Neely, David; Norreys, Peter; Santala, Marko; Zepf, Matthew; Watts, Ian; Clark, Eugene; Krushelnick, Karl; Tatarakis, Michael; Dangor, Bucker; Machecek, Antonin; Wark, Justin

    1998-12-16

    Dramatic improvements in laser technology since 1984 have revolutionised high power laser technology. Application of chirped-pulse amplification techniques has resulted in laser intensities in excess of 10{sup 19} W/cm{sup 2}. In the mid to late eighties, C. K. Rhodes and K. Boyer discussed the possibility of shining laser light of this intensity onto solid surfaces and to cause nuclear transitions. In particular, irradiation of a uranium target could induce electro- and photofission in the focal region of the laser. In this paper it is shown that {mu}Ci of {sup 62}Cu can be generated via the ({gamma},n) reaction by a laser with an intensity of about 10{sup 19} Wcm{sup -2}.

  9. Shipborne hydrographic laser scanning

    NASA Astrophysics Data System (ADS)

    Pfennigbauer, Martin; Rieger, Peter; Schaich, Martin

    2011-11-01

    Applications like hydro-archeology, hydrobiology, or hydraulic engineering sometimes require accurate surveying of submerged areas with point densities usually only achieved with mobile or terrestrial laser scanning. For navigable waterbodies, hydrographic laser scanning from a floating platform represents a viable solution. RIEGL's new hydrographic laser scanner VQ-820-G with its exceptionally high measurement rate of up to 110,000 net measurements per second and its small laser footprint is optimally suited for such applications. We present results from a measurement campaign surveying prehistoric lake dwellings at Lake Constance in Germany. While the aim of typical hydrographic laser scanning applications is to roughly acquire the ground's shape and structure, in this case it was tried to determine the exact position, shape, and attitude of the remainders of the piles. The special requirements with respect to mission planning and data processing are discussed and the performance of the laser scanner is assessed.

  10. Nanofabrication with Pulsed Lasers

    PubMed Central

    2010-01-01

    An overview of pulsed laser-assisted methods for nanofabrication, which are currently developed in our Institute (LP3), is presented. The methods compass a variety of possibilities for material nanostructuring offered by laser–matter interactions and imply either the nanostructuring of the laser-illuminated surface itself, as in cases of direct laser ablation or laser plasma-assisted treatment of semiconductors to form light-absorbing and light-emitting nano-architectures, as well as periodic nanoarrays, or laser-assisted production of nanoclusters and their controlled growth in gaseous or liquid medium to form nanostructured films or colloidal nanoparticles. Nanomaterials synthesized by laser-assisted methods have a variety of unique properties, not reproducible by any other route, and are of importance for photovoltaics, optoelectronics, biological sensing, imaging and therapeutics. PMID:20672069

  11. Micro-laser

    DOEpatents

    Hutchinson, Donald P.; Richards, Roger K.

    2003-07-22

    A micro-laser is disclosed which includes a waveguide, a first and a second subwavelength resonant grating in the waveguide, and at least one photonic band gap resonant structure (PBG) in the waveguide and at least one amplifying medium in the waveguide. PBG features are positioned between the first and second subwavelength resonant gratings and allow introduction of amplifying mediums into the highly resonant guided micro-laser microcavity. The micro-laser may be positioned on a die of a bulk substrate material with one or more electronic and optical devices and may be communicably connected to the same. A method for fabricating a micro-laser is disclosed. A method for tuning the micro-laser is also disclosed. The micro-laser may be used as an optical regenerator, or a light source for data transfer or for optical computing.

  12. Countermeasure laser development

    NASA Astrophysics Data System (ADS)

    Molocher, Bernhard

    2005-11-01

    In the whole scope of developing a countermeasure system against infrared guided missiles, the development of adequate laser sources is one of many aspects, however certainly the most demanding. The article describes from a directed infrared countermeasure (DIRCM) system aspect the functional and operational basics relevant for countering strategies. DIRCM techniques can be categorized into jamming and damaging countermeasure techniques. The resulting requirements for the countermeasure laser sources are briefly explained. Jam laser source types with advantages and drawbacks as well as possible damage laser sources, including the estimation of maturity and their specific features, are described. The FLASH countermeasure demonstrator was developed to validate the concept of having a closed loop jamming and damaging system. The laser setup for the DIRCM demonstrator FLASH is briefly described and the conducted tests including laser performance are explained.

  13. Lasers in periodontics

    PubMed Central

    Elavarasu, Sugumari; Naveen, Devisree; Thangavelu, Arthiie

    2012-01-01

    Laser is one of the most captivating technologies in dental practice since Theodore Maiman in 1960 invented the ruby laser. Lasers in dentistry have revolutionized several areas of treatment in the last three and a half decades of the 20th century. Introduced as an alternative to mechanical cutting device, laser has now become an instrument of choice in many dental applications. Evidence suggests its use in initial periodontal therapy, surgery, and more recently, its utility in salvaging implant opens up a wide range of applications. More research with better designs are a necessity before lasers can become a part of dental armamentarium. This paper gives an insight to laser in periodontics. PMID:23066266

  14. Prostate resection - minimally invasive

    MedlinePlus

    Laser prostatectomy; Transurethral needle ablation; TUNA; Transurethral incision; TUIP; Holmium laser enucleation of the prostate; HoLep; Interstitial laser coagulation; ILC; Photoselective vaporization of the prostate; PVP; Transurethral ...

  15. Excimer laser chemical problems

    SciTech Connect

    Tennant, R.; Peterson, N.

    1982-01-01

    Techniques need to be developed to maintain XeF and XeCl laser performance over long periods of time without degradation resulting from chemical processes occurring within the laser. The dominant chemical issues include optical damage, corrosions of laser materials, gas contamination, and control of halogen concentration. Each of these issues are discussed and summarized. The methods of minimizing or controlling the chemical processes involved are presented.

  16. Portable Laser Laboratory

    SciTech Connect

    Weir, J.T.

    1994-07-01

    A Portable Laser Laboratory (PLL) is being designed and built for the CALIOPE Program tests which will begin in October of 1994. The PLL is designed to give maximum flexibility for evolving laser experiments and can be readily moved by loading it onto a standard truck trailer. The internal configuration for the October experiments will support a two line DIAL system running in the mid-IR. Brief descriptions of the laser and detection systems are included.

  17. Laser In Veterinary Medicine

    NASA Astrophysics Data System (ADS)

    Newman, Carlton; Jaggar, David H.

    1982-12-01

    Lasers have been used for some time now on animals for experimental purposes prior to their use in human medical and surgical fields. However the use of lasers in veterinary medicine and surgery per se is a recent development. We describe the application of high and low intensity laser technology in a general overview of the current uses, some limitations to its use and future needs for future inquiry and development.

  18. Nd Lasers For Processing

    NASA Astrophysics Data System (ADS)

    Basiev, T. T.; Denker, B. I.; Maliutin, A. A.; Czigany, I.; Horvath, Z. G.; Kertesz, I.

    1983-10-01

    Annealing of preheated Si-samples by Nd:YAG laser is described. A Nd:YAG laser device with and without acousto-optical Q-switching for trimming, scribing, marking, drilling and medical purposes was used. The development of a portable LiNdLa-phosphate glass laser resulting in 6 % efficiency, Q-switched by LiF with F2color centers is discussed together with some of its applications.

  19. Laser cutting plastic materials

    SciTech Connect

    Van Cleave, R.A.

    1980-08-01

    A 1000-watt CO/sub 2/ laser has been demonstrated as a reliable production machine tool for cutting of plastics, high strength reinforced composites, and other nonmetals. More than 40 different plastics have been laser cut, and the results are tabulated. Applications for laser cutting described include fiberglass-reinforced laminates, Kevlar/epoxy composites, fiberglass-reinforced phenolics, nylon/epoxy laminates, ceramics, and disposable tooling made from acrylic.

  20. Precision laser aiming system

    SciTech Connect

    Ahrens, Brandon R.; Todd, Steven N.

    2009-04-28

    A precision laser aiming system comprises a disrupter tool, a reflector, and a laser fixture. The disrupter tool, the reflector and the laser fixture are configurable for iterative alignment and aiming toward an explosive device threat. The invention enables a disrupter to be quickly and accurately set up, aligned, and aimed in order to render safe or to disrupt a target from a standoff position.

  1. Polarization feedback laser stabilization

    DOEpatents

    Esherick, P.; Owyoung, A.

    1987-09-28

    A system for locking two Nd:YAG laser oscillators includes an optical path for feeding the output of one laser into the other with different polarizations. Elliptical polarization is incorporated into the optical path so that the change in polarization that occurs when the frequencies coincide may be detected to provide a feedback signal to control one laser relative to the other. 4 figs.

  2. Trends in laser micromachining

    NASA Astrophysics Data System (ADS)

    Gaebler, Frank; van Nunen, Joris; Held, Andrew

    2016-03-01

    Laser Micromachining is well established in industry. Depending on the application lasers with pulse length from μseconds to femtoseconds and wavelengths from 1064nm and its harmonics up to 5μm or 10.6μm are used. Ultrafast laser machining using pulses with pico or femtosecond duration pulses is gaining traction, as it offers very precise processing of materials with low thermal impact. Large-scale industrial ultrafast laser applications show that the market can be divided into various sub segments. One set of applications demand low power around 10W, compact footprint and are extremely sensitive to the laser price whilst still demanding 10ps or shorter laser pulses. A second set of applications are very power hungry and only become economically feasible for large scale deployments at power levels in the 100+W class. There is also a growing demand for applications requiring fs-laser pulses. In our presentation we would like to describe these sub segments by using selected applications from the automotive and electronics industry e.g. drilling of gas/diesel injection nozzles, dicing of LED substrates. We close the presentation with an outlook to micromachining applications e.g. glass cutting and foil processing with unique new CO lasers emitting 5μm laser wavelength.

  3. Optofluidic random laser

    NASA Astrophysics Data System (ADS)

    Shivakiran Bhaktha, B. N.; Bachelard, Nicolas; Noblin, Xavier; Sebbah, Patrick

    2012-10-01

    Random lasing is reported in a dye-circulated structured polymeric microfluidic channel. The role of disorder, which results from limited accuracy of photolithographic process, is demonstrated by the variation of the emission spectrum with local-pump position and by the extreme sensitivity to a local perturbation of the structure. Thresholds comparable to those of conventional microfluidic lasers are achieved, without the hurdle of state-of-the-art cavity fabrication. Potential applications of optofluidic random lasers for on-chip sensors are discussed. Introduction of random lasers in the field of optofluidics is a promising alternative to on-chip laser integration with light and fluidic functionalities.

  4. Diagrammatic semiclassical laser theory

    SciTech Connect

    Zaitsev, Oleg; Deych, Lev

    2010-02-15

    We derive semiclassical laser equations valid in all orders of nonlinearity. With the help of a diagrammatic representation, the perturbation series in powers of electric field can be resummed in terms of a certain class of diagrams. The resummation makes it possible to take into account a weak effect of population pulsations in a controlled way while treating the nonlinearity exactly. The proposed laser theory reproduces the all-order nonlinear equations in the approximation of constant population inversion and the third-order equations with population-pulsation terms as special cases. The theory can be applied to arbitrarily open and irregular lasers, such as random lasers.

  5. LCLS Injector Drive Laser

    SciTech Connect

    Dowell, D.H.; Castro, J.; Emma, P.; Frisch, J.; Gilevich, A.; Hays, G.; Hering, P.; Limborg-Deprey, C.; Loos, H.; Miahnahri, A.; White, W.; /SLAC

    2007-11-02

    Requirements for the LCLS injector drive laser present significant challenges to the design of the system. While progress has been demonstrated in spatial shape, temporal shape, UV generation and rep-rate, a laser that meets all of the LCLS specifications simultaneously has yet to be demonstrated. These challenges are compounded by the stability and reliability requirements. The drive laser and transport system has been installed and tested. We will report on the current operational state of the laser and plans for future improvements.

  6. Fusion reactor pumped laser

    DOEpatents

    Jassby, Daniel L.

    1988-01-01

    A nuclear pumped laser capable of producing long pulses of very high power laser radiation is provided. A toroidal fusion reactor provides energetic neutrons which are slowed down by a moderator. The moderated neutrons are converted to energetic particles capable of pumping a lasing medium. The lasing medium is housed in an annular cell surrounding the reactor. The cell includes an annular reflecting mirror at the bottom and an annular output window at the top. A neutron reflector is disposed around the cell to reflect escaping neutrons back into the cell. The laser radiation from the annular window is focused onto a beam compactor which generates a single coherent output laser beam.

  7. Laser aircraft. [using kerosene

    NASA Technical Reports Server (NTRS)

    Hertzberg, A.; Sun, K.; Jones, W. S.

    1979-01-01

    The concept of a laser-powered aircraft is discussed. Laser flight would be completely compatible with existing airports and air-traffic control, with the airplane using kerosene only power, up to a cruising altitude of 9 km where the laser satellite would lock on and beam laser energy to it. Two major components make up the laser turbofan, a heat exchanger for converting laser radiation into thermal energy, and conventional turbomachinery. The laser power satellite would put out 42 Mw using a solar-powered thermal engine to generate electrical power for the closed-cycle supersonic electric discharge CO laser, whose radiators, heat exchangers, supersonic diffuser, and ducting will amount to 85% of the total subsystem mass. Relay satellites will be used to intercept the beam from the laser satellite, correct outgoing beam aberrations, and direct the beam to the next target. A 300-airplane fleet with transcontinental range is projected to save enough kerosene to equal the energy content of the entire system, including power and relay satellites, in one year.

  8. Gigashot Optical Laser Demonstrator

    SciTech Connect

    Deri, R. J.

    2015-10-13

    The Gigashot Optical Laser Demonstrator (GOLD) project has demonstrated a novel optical amplifier for high energy pulsed lasers operating at high repetition rates. The amplifier stores enough pump energy to support >10 J of laser output, and employs conduction cooling for thermal management to avoid the need for expensive and bulky high-pressure helium subsystems. A prototype amplifier was fabricated, pumped with diode light at 885 nm, and characterized. Experimental results show that the amplifier provides sufficient small-signal gain and sufficiently low wavefront and birefringence impairments to prove useful in laser systems, at repetition rates up to 60 Hz.

  9. Laser welding in space

    NASA Technical Reports Server (NTRS)

    Kaukler, W. F.; Workman, G. L.

    1991-01-01

    Autogenous welds in 304 stainless steel were performed by Nd-YAG laser heating in a simulated space environment. Simulation consists of welding on the NASA KC-135 aircraft to produce the microgravity and by containing the specimen in a vacuum chamber. Experimental results show that the microgravity welds are stronger, harder in the fusion zone, have deeper penetration and have a rougher surface rippling of the weld pool than one-g welds. To perform laser welding in space, a solar-pumped laser concept that significantly increases the laser conversion efficiency and makes welding viable despite the limited power availability of spacecraft is proposed.

  10. Progress in alexandrite lasers

    NASA Astrophysics Data System (ADS)

    Shand, M. L.

    Technology developments aimed at improving alexandrite laser systems are described. The effects of a low emission cross section, high damage probability, short fluorescence lifetime, and high thermal lensing on the performance of the laser are examined. The uses of higher temperatures, an improved resonator design, and high power flashlamp pumping to counter the effects of low gain are discussed. A change in rod orientation and the utilization of thermal lensing insensitive resonators to enhance thermal lensing are proposed. Consideration is given to the different types of damage possible in alexandrite lasers, and the lifetime of the lasers.

  11. Shuttle Laser Altimeter

    NASA Technical Reports Server (NTRS)

    Bufton, Jack L.; Harding, David J.; Garvin, James B.

    1999-01-01

    The Shuttle Laser Altimeter (SLA) is a Hitchhiker experiment that has flown twice; first on STS-72 in January 1996 and then on STS-85 in August 1997. Both missions produced successful laser altimetry and surface lidar data products from approximately 80 hours per mission of SLA data operations. A total of four Shuttle missions are planned for the SLA series. This paper documents SLA mission results and explains SLA pathfinder accomplishments at the mid-point in this series of Hitchhiker missions. The overall objective of the SLA mission series is the transition of the Goddard Space Flight Center airborne laser altimeter and lidar technology to low Earth orbit as a pathfinder for NASA operational space-based laser remote sensing devices. Future laser altimeter sensors will utilize systems and approaches being tested with SLA, including the Multi-Beam Laser Altimeter (MBLA) and the Geoscience Laser Altimeter System (GLAS). MBLA is the land and vegetation laser sensor for the NASA Earth System Sciences Pathfinder Vegetation Canopy Lidar (VCL) Mission, and GLAS is the Earth Observing System facility instrument on the Ice, Cloud, and Land Elevation Satellite (ICESat). The Mars Orbiting Laser Altimeter, now well into a multi-year mapping mission at the red planet, is also directly benefiting from SLA data analysis methods, just as SLA benefited from MOLA spare parts and instrument technology experience [5] during SLA construction in the early 1990s.

  12. Deep space laser communications

    NASA Astrophysics Data System (ADS)

    Biswas, Abhijit; Kovalik, Joseph M.; Srinivasan, Meera; Shaw, Matthew; Piazzolla, Sabino; Wright, Malcolm W.; Farr, William H.

    2016-03-01

    A number of laser communication link demonstrations from near Earth distances extending out to lunar ranges have been remarkably successful, demonstrating the augmented channel capacity that is accessible with the use of lasers for communications. The next hurdle on the path to extending laser communication and its benefits throughout the solar system and beyond is to demonstrate deep-space laser communication links. In this paper, concepts and technology development being advanced at the Jet Propulsion Laboratory (JPL) in order to enable deep-space link demonstrations to ranges of approximately 3 AU in the next decade, will be discussed.

  13. Laser applications in phlebology

    NASA Astrophysics Data System (ADS)

    Longo, Leonardo; Mancini, S.; Postiglione, Marco; Postiglione, M. G.

    2001-06-01

    PURPOSE: review of laser used in phlebology METHOD: critical analysis of scientific data taken from the literature and based on 25 years personal experience. RESULTS: we have three groups of laser applications in phlebology: for the diagnosis, as physical therapy and as surgical therapy. DISCUSSION AND CONCLUSION: the laser-doppler studies the microcirculations, the no-surgical therapy shown positive results in the treatment of venous ulcers and for the wound healing. It could be indicate also as antiphlogistic and anti-edema therapy, in superficial thrombophlebitis. The surgical laser is useful for the surgical cleaning of ulcers, for haemorroids, angiomas and telangiectases.

  14. Laser processing with specially designed laser beam

    NASA Astrophysics Data System (ADS)

    Asratyan, A. A.; Bulychev, N. A.; Feofanov, I. N.; Kazaryan, M. A.; Krasovskii, V. I.; Lyabin, N. A.; Pogosyan, L. A.; Sachkov, V. I.; Zakharyan, R. A.

    2016-04-01

    The possibility of using laser systems to form beams with special spatial configurations has been studied. The laser systems applied had a self-conjugate cavity based on the elements of copper vapor lasers (LT-5Cu, LT-10Cu, LT-30Cu) with an average power of 5, 10, or 30 W. The active elements were pumped by current pulses of duration 80-100 ns. The duration of laser generation pulses was up to 25 ns. The generator unit included an unstable cavity, where one reflector was a special mirror with a reflecting coating. Various original optical schemes used were capable of exploring spatial configurations and energy characteristics of output laser beams in their interaction with micro- and nanoparticles fabricated from various materials. In these experiments, the beam dimensions of the obtained zones varied from 0.3 to 5 µm, which is comparable with the minimum permissible dimensions determined by the optical elements applied. This method is useful in transforming a large amount of information at the laser pulse repetition rate of 10-30 kHz. It was possible to realize the high-precision micromachining and microfabrication of microscale details by direct writing, cutting and drilling (with the cutting width and through-hole diameters ranging from 3 to 100 µm) and produce microscale, deep, intricate and narrow grooves on substrate surfaces of metals and nonmetal materials. This system is used for producing high-quality microscale details without moving the object under treatment. It can also be used for microcutting and microdrilling in a variety of metals such as molybdenum, copper and stainless steel, with a thickness of up to 300 µm, and in nonmetals such as silicon, sapphire and diamond with a thickness ranging from 10 µm to 1 mm with different thermal parameters and specially designed laser beam.

  15. Laser Program annual report 1987

    SciTech Connect

    O'Neal, E.M.; Murphy, P.W.; Canada, J.A.; Kirvel, R.D.; Peck, T.; Price, M.E.; Prono, J.K.; Reid, S.G.; Wallerstein, L.; Wright, T.W.

    1989-07-01

    This report discusses the following topics: target design and experiments; target materials development; laboratory x-ray lasers; laser science and technology; high-average-power solid state lasers; and ICF applications studies.

  16. Laser peening with fiber optic delivery

    DOEpatents

    Friedman, Herbert W.; Ault, Earl R.; Scheibner, Karl F.

    2004-11-16

    A system for processing a workpiece using a laser. The laser produces at least one laser pulse. A laser processing unit is used to process the workpiece using the at least one laser pulse. A fiber optic cable is used for transmitting the at least one laser pulse from the laser to the laser processing unit.

  17. Compact Ho:YLF Laser

    NASA Technical Reports Server (NTRS)

    Hemmati, H.

    1988-01-01

    Longitudinal pumping by laser diodes increases efficiency. Improved holmium:yttrium lithium fluoride laser radiates as much as 56 mW of power at wavelength of 2.1 micrometer. New Ho:YLF laser more compact and efficient than older, more powerful devices of this type. Compact, efficient Ho:YLF laser based on recent successes in use of diode lasers to pump other types of solid-state lasers.

  18. High power solid state lasers

    SciTech Connect

    Weber, H.

    1988-01-01

    These proceedings discuss the following subjects: trends in materials processing with laser radiation; slabs and high power systems; glasses and new crystals; solid state lasers at HOYA Corp.; lamps, resonators and transmission; glasses as active materials for high average power solid state lasers; flashlamp pumped GGG-crystals; alexandrite lasers; designing telescope resonators; mode operation of neodymium: YAG lasers; intracavity frequency doubling with KTP crystal and thermal effects in cylinder lasers.

  19. High-power pulsed lasers

    SciTech Connect

    Holzrichter, J.F.

    1980-04-02

    The ideas that led to the successful construction and operation of large multibeam fusion lasers at the Lawrence Livermore Laboratory are reviewed. These lasers are based on the use of Nd:glass laser materials. However, most of the concepts are applicable to any laser being designed for fusion experimentation. This report is a summary of lectures given by the author at the 20th Scottish University Summer School in Physics, on Laser Plasma Interaction. This report includes basic concepts of the laser plasma system, a discussion of lasers that are useful for short-pulse, high-power operation, laser design constraints, optical diagnostics, and system organization.

  20. Lasers '83. Proceedings of the international conference

    SciTech Connect

    Powell, R.C.

    1985-01-01

    Among the topics discussed are the development history of the semiconductor diode laser, laser material processing, nonlinear spectroscopy, recent advancements in diode lasers, laser-driven particle accelerators, laser applications in the atmospheric sciences, laser-assisted collisions, novel (garnet and alexandrite) solid state laser materials, IR molecular lasers, devices and components for fiber-optic communications, free-electron lasers and masers, and picosecond optical phenomena. Also covered are laser-stimulated materials surface processes, color center laser developments, blue-green and metal vapor lasers, laser chemistry, nonlinear effects, high energy lasers, excimer lasers, laser trapping of ions, optical cavities and propagation, laser isotope separation, laser trapping of atoms, laser applications in biochemistry, tunable coherent short wavelength radiation, laser spectroscopy, picosecond studies of condensed phase molecular systems, and combustion and plasma diagnostics.

  1. Compact laser sources for laser designation, ranging and active imaging

    NASA Astrophysics Data System (ADS)

    Goldberg, Lew; Nettleton, John; Schilling, Brad; Trussel, Ward; Hays, Alan

    2007-04-01

    Recent advances in compact solid sate lasers for laser designation, eye-safe range finding and active imaging are described. Wide temperature operation of a compact Nd:YAG laser was achieved by end pumping and the use of multi-λ diode stacks. Such lasers enabled construction of fully operational 4.7 lb laser designator prototypes generating over 50 mJ at 10-20 Hz PRF. Output pulse energy in excess of 100 mJ was demonstrated in a breadboard version of the end-pumped laser. Eye-safe 1.5 μm lasers based on flash-pumped, low PRF, Monoblock lasers have enabled compact STORM laser range finders that have recently been put into production. To achieve higher optical and electrical efficiency needed for higher PRF operation, Monoblock lasers were end-pumped by a laser diode stack. Laser diode end-pumped Monoblock lasers were operated at 10-20 Hz PRF over a wide temperature range (-20 to +50 °C). Compared with bulk compact solid state lasers, fiber lasers are characterized by lower pulse energy, higher PRF's, shorter pulses and higher electrical efficiency. An example of fiber lasers suitable for LIDAR, and atmospheric measurement applications is described. Eye-safe, low intensity diode pumped solid state green warning laser developed for US Army checkpoint and convoy applications is also described.

  2. Laser Ranging Simulation Program

    NASA Technical Reports Server (NTRS)

    Piazolla, Sabino; Hemmati, Hamid; Tratt, David

    2003-01-01

    Laser Ranging Simulation Program (LRSP) is a computer program that predicts selected aspects of the performances of a laser altimeter or other laser ranging or remote-sensing systems and is especially applicable to a laser-based system used to map terrain from a distance of several kilometers. Designed to run in a more recent version (5 or higher) of the MATLAB programming language, LRSP exploits the numerical and graphical capabilities of MATLAB. LRSP generates a graphical user interface that includes a pop-up menu that prompts the user for the input of data that determine the performance of a laser ranging system. Examples of input data include duration and energy of the laser pulse, the laser wavelength, the width of the laser beam, and several parameters that characterize the transmitting and receiving optics, the receiving electronic circuitry, and the optical properties of the atmosphere and the terrain. When the input data have been entered, LRSP computes the signal-to-noise ratio as a function of range, signal and noise currents, and ranging and pointing errors.

  3. Longitudinal discharge laser electrodes

    DOEpatents

    Warner, B.E.; Miller, J.L.; Ault, E.R.

    1994-08-23

    The improved longitudinal discharge laser electrode with IR baffle includes an electrode made up of washers spaced along the laser axis in order to form inter-washer spaces for hollow cathode discharge to take place and for IR radiation to be trapped. Additional IR baffles can be placed between the electrode ann the window. 2 figs.

  4. Longitudinal discharge laser electrodes

    DOEpatents

    Warner, Bruce E.; Miller, John L.; Ault, Earl R.

    1994-01-01

    The improved longitudinal discharge laser electrode with IR baffle includes an electrode made up of washers spaced along the laser axis in order to form inter-washer spaces for hollow cathode discharge to take place and for IR radiation to be trapped. Additional IR baffles can be placed between the electrode ann the window.

  5. Liquid laser cavities

    NASA Technical Reports Server (NTRS)

    Bjorklund, S.; Filipescu, N.; Kellermeyer, G. L.; Mc Avoy, N.

    1969-01-01

    Liquid laser cavities have plenum chambers at the ends of the capillary cell which are terminated in transparent optical flats. By use of these cavities, several new europium chelates and a terbium chelate can provide laser action in solution at room temperature.

  6. Learning about Lasers

    ERIC Educational Resources Information Center

    Roberts, Larry

    2011-01-01

    The word laser is an acronym. It stands for Light Amplification by Stimulated Emission of Radiation. Lasers, invented in 1958, are used to cut and fuse materials, accurately survey long distances, communicate across fiber-optic phone lines, produce 3D pictures, make special effects, help navigation, and read bar codes for cash registers. A laser…

  7. Liquid heat capacity lasers

    DOEpatents

    Comaskey, Brian J.; Scheibner, Karl F.; Ault, Earl R.

    2007-05-01

    The heat capacity laser concept is extended to systems in which the heat capacity lasing media is a liquid. The laser active liquid is circulated from a reservoir (where the bulk of the media and hence waste heat resides) through a channel so configured for both optical pumping of the media for gain and for light amplification from the resulting gain.

  8. Laser Scanning In Inspection

    NASA Astrophysics Data System (ADS)

    West, Patricia; Baker, Lionel R.

    1989-03-01

    This paper is a review of the applications of laser scanning in inspection. The reasons for the choice of a laser in flying spot scanning and the optical properties of a laser beam which are of value in a scanning instrument will be given. The many methods of scanning laser beams in both one and two dimensions will be described. The use of one dimensional laser scanners for automatic surface inspection for transmitting and reflective products will be covered in detail, with particular emphasis on light collection techniques. On-line inspection applications which will be mentioned include: photographic film web, metal strip products, paper web, glass sheet, car body paint surfaces and internal cylinder bores. Two dimensional laser scanning is employed in applications where increased resolution, increased depth of focus, and better contrast are required compared with conventional vidicon TV or solid state array cameras. Such examples as special microscope laser scanning systems and a TV compatible system for use in restricted areas of a nuclear reactor will be described. The technical and economic benefits and limitations of laser scanning video systems will be compared with conventional TV and CCD array devices.

  9. Laser biostimulation in pediatrics

    NASA Astrophysics Data System (ADS)

    Utz, Irina A.; Lagutina, L. E.; Tuchin, Valery V.

    1995-01-01

    In the present paper the method and apparatus for percutaneous laser irradiation of blood (PLIB) in vessels (veins) are described. Results of clinical investigations of biostimulating effects under PLIB by red laser light (633 nm) in Cubiti and Saphena Magna veins are presented.

  10. Laser Damage Lab

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Optical Damage Threshold Testing Instrumentation at NASA Langley Research Center. This work was sanctioned and funded by Code Q, R, & AE to develop a new standard for damage testing various types of optical materials and coatings. Laser Induced Damage Threshold (LIDT) testing is a destructive test procedure to determine the minimum applied laser energy level that will result in damage and is referred to as the damage threshold. The damage threshold is often the critical limitation in the section of optical materials for use in high-energy laser systems.The test station consists of diagnostic equipment, beam conditioning optical elements, an inspection microscope and three lasers: a high energy pulsed ND: Yag, which develops 650mJ at 10 hz and outputs three wavelengths which include 1.06m, 532nm and 355 nm; a Ti:sapphire laser which produces a continuum of laser output from 790nm to 900nm; and a alignment HeNe, which looks yellow when mixed with the 2nd harmonic ND:Yag laser. Laser sources are used to perform damage threshold testing at the specific wavelength of interest.

  11. Optofluidic chlorophyll lasers.

    PubMed

    Chen, Yu-Cheng; Chen, Qiushu; Fan, Xudong

    2016-06-21

    Chlorophylls are essential for photosynthesis and also one of the most abundant pigments on earth. Using an optofluidic ring resonator of extremely high Q-factors (>10(7)), we investigated the unique characteristics and underlying mechanism of chlorophyll lasers. Chlorophyll lasers with dual lasing bands at 680 nm and 730 nm were observed for the first time in isolated chlorophyll a (Chla). Particularly, a laser at the 730 nm band was realized in 0.1 mM Chla with a lasing threshold of only 8 μJ mm(-2). Additionally, we observed lasing competition between the two lasing bands. The presence of laser emission at the 680 nm band can lead to quenching or significant reduction of laser emission at the 730 nm band, effectively increasing the lasing threshold for the 730 nm band. Further concentration-dependent studies, along with theoretical analysis, elucidated the mechanism that determines when and why the laser emission band appears at one of the two bands, or concomitantly at both bands. Finally, Chla was exploited as the donor in fluorescence resonance energy transfer to extend the laser emission to the near infrared regime with an unprecedented wavelength shift as large as 380 nm. Our work will open a door to the development of novel biocompatible and biodegradable chlorophyll-based lasers for various applications such as miniaturized tunable coherent light sources and in vitro/in vivo biosensing. It will also provide important insight into the chlorophyll fluorescence and photosynthesis processes inside plants. PMID:27220992

  12. Infrared laser bone ablation

    SciTech Connect

    Nuss, R.C.; Fabian, R.L.; Sarkar, R.; Puliafito, C.A.

    1988-01-01

    The bone ablation characteristics of five infrared lasers, including three pulsed lasers (Nd:YAG, lambda = 1064 micron; Hol:YSGG, lambda = 2.10 micron; and Erb:YAG, lambda = 2.94 micron) and two continuous-wave lasers (Nd:YAG, lambda = 1.064 micron; and CO/sub 2/, lambda = 10.6 micron), were studied. All laser ablations were performed in vitro, using moist, freshly dissected calvarium of guinea pig skulls. Quantitative etch rates of the three pulsed lasers were calculated. Light microscopy of histologic sections of ablated bone revealed a zone of tissue damage of 10 to 15 micron adjacent to the lesion edge in the case of the pulsed Nd:YAG and the Erb:YAG lasers, from 20 to 90 micron zone of tissue damage for bone ablated by the Hol:YSGG laser, and 60 to 135 micron zone of tissue damage in the case of the two continuous-wave lasers. Possible mechanisms of bone ablation and tissue damage are discussed.

  13. Explosively pumped laser light

    DOEpatents

    Piltch, Martin S.; Michelotti, Roy A.

    1991-01-01

    A single shot laser pumped by detonation of an explosive in a shell casing. The shock wave from detonation of the explosive causes a rare gas to luminesce. The high intensity light from the gas enters a lasing medium, which thereafter outputs a pulse of laser light to disable optical sensors and personnel.

  14. Lasers for Training Devices.

    ERIC Educational Resources Information Center

    Fuller, C. A.

    A breadboard model of a laser display system is described in detail and its operating procedure is outlined. The system consists of: a Model 52 argon krypton ion laser and power supply; an optical breadboard comprising a pocket cell light modulator, a galvonmeter beam deflector for vertical scanning, a unique multiple reflection beam steerer for…

  15. Laser hair removal pearls.

    PubMed

    Tierney, Emily P; Goldberg, David J

    2008-03-01

    A number of lasers and light devices are now available for the treatment of unwanted hair. The goal of laser hair removal is to damage stem cells in the bulge of the follicle through the targeting of melanin, the endogenous chromophore for laser and light devices utilized to remove hair. The competing chromophores in the skin and hair, oxyhemoglobin and water, have a decreased absorption between 690 nm and 1000 nm, thus making this an ideal range for laser and light sources. Pearls of laser hair removal are presented in this review, focusing on four areas of recent development: 1 treatment of blond, white and gray hair; 2 paradoxical hypertrichosis; 3 laser hair removal in children; and 4 comparison of lasers and IPL. Laser and light-based technologies to remove hair represents one of the most exciting areas where discoveries by dermatologists have led to novel treatment approaches. It is likely that in the next decade, continued advancements in this field will bring us closer to the development of a more permanent and painless form of hair removal. PMID:18330794

  16. Laser Chemical Analysis.

    ERIC Educational Resources Information Center

    Zare, Richard N.

    1984-01-01

    Reviews applications of laser methods to analytical problems, selecting examples from multiphoton ionization and fluorescence analysis. Indicates that laser methodologies promise to improve dramatically the detection of trace substances embedded in "real" matrices, giving the analyst a most powerful means for determining the composition of…

  17. Athermal laser design.

    PubMed

    Bovington, Jock; Srinivasan, Sudharsanan; Bowers, John E

    2014-08-11

    This paper discusses circuit based and waveguide based athermalization schemes and provides some design examples of athermalized lasers utilizing fully integrated athermal components as an alternative to power hungry thermo-electric controllers (TECs), off-chip wavelength lockers or monitors with lookup tables for tunable lasers. This class of solutions is important for uncooled transmitters on silicon. PMID:25321020

  18. Hypopyon following laser iridotomy.

    PubMed

    Cohen, J S; Bibler, L; Tucker, D

    1984-07-01

    Two patients who had laser iridotomy performed for pupillary block glaucoma developed hypopyon following surgery. One case had iris bombé with rubeosis iridis, and the other had chronic angle closure glaucoma. Factors contributing to inflammation and possible hypopyon following laser iridotomy are discussed. PMID:6472786

  19. Green pumped Alexandrite lasers

    NASA Astrophysics Data System (ADS)

    Kuper, Jerry W.; Brown, David C.

    2005-04-01

    Initial experiments with pulsed and CW pumping an alexandrite laser rod at 532 nm are presented. This pumping architecture holds promise for the production of scalable diode-pumped, tunable alexandrite laser systems operating in the near infrared (750 nm), and the ultraviolet (375 and 250 nm) spectral regions.

  20. Coaxial short pulsed laser

    DOEpatents

    Nelson, M.A.; Davies, T.J.

    1975-08-01

    This invention relates to a laser system of rugged design suitable for use in a field environment. The laser itself is of coaxial design with a solid potting material filling the space between components. A reservoir is employed to provide a gas lasing medium between an electrode pair, each of which is connected to one of the coaxial conductors. (auth)

  1. Solid state laser

    NASA Technical Reports Server (NTRS)

    Rines, Glen A. (Inventor); Moulton, Peter F. (Inventor); Harrison, James (Inventor)

    1993-01-01

    A wavelength-tunable, injection-seeded, dispersion-compensated, dispersively-pumped solid state laser includes a lasing medium; a highly reflective mirror; an output coupler; at least one isosceles Brewster prism oriented to the minimum deviation angle between the medium and the mirror for directing light of different wavelengths along different paths; means for varying the angle of the highly reflective mirror relative to the light from at least one Brewster angle for selecting a predetermined laser operating wavelength; a dispersion compensation apparatus associated with the lasing medium; a laser injection seeding port disposed between the dispersion compensation apparatus and one of the mirror and coupler and including a reflective surface at an acute non-Brewster angle to the laser beam for introducing a seed input; a dispersion compensation apparatus associated with the laser medium including opposite chirality optical elements; the lasing medium including a pump surface disposed at an acute angle to the laser beam to define a discrete path for the pumping laser beam separate from the pumped laser beam.

  2. Dye laser amplifier

    DOEpatents

    Moses, E.I.

    1992-12-01

    An improved dye laser amplifier is disclosed. The efficiency of the dye laser amplifier is increased significantly by increasing the power of a dye beam as it passes from an input window to an output window within the dye chamber, while maintaining the intensity of the dye beam constant. 3 figs.

  3. Sunlight-Pumped Laser

    NASA Technical Reports Server (NTRS)

    Weaver, W. R. J.; Lee, J. H.

    1982-01-01

    Organic iodide gas is stimulated by portion of Sun's spectrum to emit laser light. Chopper forms pulses from beam of Xenon-Arc light. Chopper is only necessary to avoid buildup of laser-quenching species in sealed tube of present experiment. Perfluoropropyliodide lasing medium functions at temperatures of about 670 K, a fact that reduces cooling requirements in space.

  4. Laser energy conversion

    NASA Technical Reports Server (NTRS)

    Jalufka, N. W.

    1989-01-01

    The conversion of laser energy to other, more useful, forms is an important element of any space power transmission system employing lasers. In general the user, at the receiving sight, will require the energy in a form other than laser radiation. In particular, conversion to rocket power and electricity are considered to be two major areas where one must consider various conversion techniques. Three systems (photovoltaic cells, MHD generators, and gas turbines) have been identified as the laser-to-electricity conversion systems that appear to meet most of the criteria for a space-based system. The laser thruster also shows considerable promise as a space propulsion system. At this time one cannot predict which of the three laser-to-electric converters will be best suited to particular mission needs. All three systems have some particular advantages, as well as disadvantages. It would be prudent to continue research on all three systems, as well as the laser rocket thruster. Research on novel energy conversion systems, such as the optical rectenna and the reverse free-electron laser, should continue due to their potential for high payoff.

  5. Fine welding with lasers.

    PubMed

    MacLellan, D

    2008-01-01

    The need for micro joining metallic alloys for surgical instruments, implants and advanced medical devices is driving a rapid increase in the implementation of laser welding technology in research, development and volume production. This article discusses the advantages of this welding method and the types of lasers used in the process. PMID:18557404

  6. Distributed ultrafast fibre laser

    PubMed Central

    Liu, Xueming; Cui, Yudong; Han, Dongdong; Yao, Xiankun; Sun, Zhipei

    2015-01-01

    A traditional ultrafast fibre laser has a constant cavity length that is independent of the pulse wavelength. The investigation of distributed ultrafast (DUF) lasers is conceptually and technically challenging and of great interest because the laser cavity length and fundamental cavity frequency are changeable based on the wavelength. Here, we propose and demonstrate a DUF fibre laser based on a linearly chirped fibre Bragg grating, where the total cavity length is linearly changeable as a function of the pulse wavelength. The spectral sidebands in DUF lasers are enhanced greatly, including the continuous-wave (CW) and pulse components. We observe that all sidebands of the pulse experience the same round-trip time although they have different round-trip distances and refractive indices. The pulse-shaping of the DUF laser is dominated by the dissipative processes in addition to the phase modulations, which makes our ultrafast laser simple and stable. This laser provides a simple, stable, low-cost, ultrafast-pulsed source with controllable and changeable cavity frequency. PMID:25765454

  7. Lasers in diagnostic dentistry

    NASA Astrophysics Data System (ADS)

    Khorana, Brij M.

    1996-09-01

    Results of a new noninvasive technique for pulp detection that is based on monitoring the time variations in the laser speckle pattern from a human tooth are presented. The paper also contains preliminary results of experiments and attempts at mathematical modeling of multiple scattering of a laser beam from a solid cylinder.

  8. Explosively pumped laser light

    SciTech Connect

    Piltch, M.S.; Michelott, R.A.

    1991-09-24

    This patent describes a single shot laser pumped by detonation of an explosive in a shell casing. The shock wave from detonation of the explosive causes a rare gas to luminesce. The high intensity light from the gas enters a lasing medium, which thereafter outputs a pulse of laser light to disable optical sensors and personnel.

  9. Dielectric laser accelerators

    NASA Astrophysics Data System (ADS)

    England, R. Joel; Noble, Robert J.; Bane, Karl; Dowell, David H.; Ng, Cho-Kuen; Spencer, James E.; Tantawi, Sami; Wu, Ziran; Byer, Robert L.; Peralta, Edgar; Soong, Ken; Chang, Chia-Ming; Montazeri, Behnam; Wolf, Stephen J.; Cowan, Benjamin; Dawson, Jay; Gai, Wei; Hommelhoff, Peter; Huang, Yen-Chieh; Jing, Chunguang; McGuinness, Christopher; Palmer, Robert B.; Naranjo, Brian; Rosenzweig, James; Travish, Gil; Mizrahi, Amit; Schachter, Levi; Sears, Christopher; Werner, Gregory R.; Yoder, Rodney B.

    2014-10-01

    The use of infrared lasers to power optical-scale lithographically fabricated particle accelerators is a developing area of research that has garnered increasing interest in recent years. The physics and technology of this approach is reviewed, which is referred to as dielectric laser acceleration (DLA). In the DLA scheme operating at typical laser pulse lengths of 0.1 to 1 ps, the laser damage fluences for robust dielectric materials correspond to peak surface electric fields in the GV /m regime. The corresponding accelerating field enhancement represents a potential reduction in active length of the accelerator between 1 and 2 orders of magnitude. Power sources for DLA-based accelerators (lasers) are less costly than microwave sources (klystrons) for equivalent average power levels due to wider availability and private sector investment. Because of the high laser-to-particle coupling efficiency, required pulse energies are consistent with tabletop microJoule class lasers. Combined with the very high (MHz) repetition rates these lasers can provide, the DLA approach appears promising for a variety of applications, including future high-energy physics colliders, compact light sources, and portable medical scanners and radiative therapy machines.

  10. Surface treatments by laser

    NASA Astrophysics Data System (ADS)

    Thomann, A. L.; Benzerga, R.; Basillais, Armelle; Georges, Cecile; Fariaut, Francois; Semmar, Nadjib; Boulmer-Leborgne, Chantal

    2003-07-01

    Laser treatments of various metals are studying depending on the laser wavelength, pulse time duration and shape, and fluence (laser/metal interaction regime). Low fluence excimer UV laser melting process of gold layer is shown to improve the corrosion resistance of multilayer (Au/Ni/Cu alloy) electrical contacts. For this application the homogenity of the laser beam as well as the initial Cu substrate roughness are found to be limiting parameters of the process. Carburization of Al alloy, performed in C3H6 atmosphere with a KrF laser induces the incorporation of carbon atoms over about 4 μm depth. The crystalline Al4C3 synthesized at the surface leads to a strengthening of the light Al alloy, which is of great interest for application in car industry. The study shows that diffusion of C atom in the target is possible because of a plasma presence on the surface which supports the molten bath life time and induces dissociation of the ambient gas. In the last example of laser metal surface treatment presented in that paper, a commonly used steel is treated in air with different lasers at a fluence above the plasma formation threshold. It is seen that the machining oils covering the surface before the treatment can be efficiently removed and that new compounds (nitride, carbide and oxides) are formed at the surface.

  11. Laser Programs Highlight 1995

    SciTech Connect

    Jacobs, R.R.

    1997-01-31

    Our contributions to laser science and technology and corresponding applications range from concept to design of the National Ignition Facility, transfer of Atomic Vapor Laser Isotope Separation technology to the private sector, and from new initiatives in industry and defense to micro-optics for improving human vision.

  12. The Human Laser.

    ERIC Educational Resources Information Center

    Guerra, David V.

    1996-01-01

    Presents a participation activity for students of all ages that stimulates the processes that occur in the build-up of a laser pulse. Exposes students to the concepts of coherence, monochromaticity, stimulated emission, pulse build-up from background fluctuations, and the properties that dictate the shape of a typical laser pulse. (JRH)

  13. Free-Electron Lasers.

    ERIC Educational Resources Information Center

    Brau, Charles A.

    1988-01-01

    Describes the use of free-electron lasers as a source of coherent radiation over a broad range of wavelengths from the far-infrared to the far-ultraviolet regions of the spectrum. Discusses some applications of these lasers, including medicine and strategic defense. (TW)

  14. LIL laser performance status

    NASA Astrophysics Data System (ADS)

    Julien, Xavier; Adolf, Alain; Bar, Emmanuel; Beau, Vincent; Bordenave, Edouard; Chiès, Thierry; Courchinoux, Roger; Di-Nicola, Jean-Michel; Féral, Christophe; Gendeau, Patrick; Graillot, Hervé; Grosset-Grange, Claire; Henry, Olivier; Higonenq, Vincent; Journot, Eric; Lacampagne, Lionel; Lafond, Eric; Le Déroff, Laurent; Martinez, Arnaud; Patissou, Loic; Roques, Alain; Thauvin, Ludovic; Thiell, Gaston

    2011-03-01

    The Laser Integration Line (LIL) was first designed as a prototype to validate the concepts and the laser architecture of the Laser MegaJoule (LMJ). The LIL facility is a 4-beam laser representing a quad structure of the LMJ. A set of test campaigns were conducted to safely ramp up laser performance. The main goal was to measure quad-specific features such as beam synchronization and focal spot (size, smoothing contrast ratio or irradiation nonuniformity) versus the LMJ requirements. Following the laser commissioning, the LIL has become a major instrument dedicated to the achievement of plasma physics experiments for the French Simulation Program and was also opened to the academic scientific community. One of the attributes of the LIL facility is to be very flexible to accommodate the requests of plasma physicists during campaigns. The LIL is constantly evolving to best meet the needs of target physicists. Changes made or planned are either to improve the quality of laser beams, or to increase the LIL Energy-Power operating space. To optimize preparation and design of shot campaigns, the LIL performance status has been elaborated. It gives information about the characteristics of the laser in terms of near field and far field, defines the steps to maintain performance, explains how the facility responds to the request, details settings (smoothing, shaping of the focal spot, energy, temporal pulse shaping, beam pointing) and gives the limits in energy and power. In this paper, an overview of the LIL performance is presented.

  15. Coherent Polariton Laser

    NASA Astrophysics Data System (ADS)

    Kim, Seonghoon; Zhang, Bo; Wang, Zhaorong; Fischer, Julian; Brodbeck, Sebastian; Kamp, Martin; Schneider, Christian; Höfling, Sven; Deng, Hui

    2016-01-01

    The semiconductor polariton laser promises a new source of coherent light, which, compared to conventional semiconductor photon lasers, has input-energy threshold orders of magnitude lower. However, intensity stability, a defining feature of a coherent state, has remained poor. Intensity noise many times the shot noise of a coherent state has persisted, attributed to multiple mechanisms that are difficult to separate in conventional polariton systems. The large intensity noise, in turn, limits the phase coherence. Thus, the capability of the polariton laser as a source of coherence light is limited. Here, we demonstrate a polariton laser with shot-noise-limited intensity stability, as expected from a fully coherent state. This stability is achieved by using an optical cavity with high mode selectivity to enforce single-mode lasing, suppress condensate depletion, and establish gain saturation. Moreover, the absence of spurious intensity fluctuations enables the measurement of a transition from exponential to Gaussian decay of the phase coherence of the polariton laser. It suggests large self-interaction energies in the polariton condensate, exceeding the laser bandwidth. Such strong interactions are unique to matter-wave lasers and important for nonlinear polariton devices. The results will guide future development of polariton lasers and nonlinear polariton devices.

  16. Energy transmission by laser

    NASA Astrophysics Data System (ADS)

    Apollonov, V. V.

    2015-02-01

    Laser spark obtained by using a conical optics is much more appropriate to form conducting channels in atmosphere. Only two types of lasers are actively considered to be used in forming high-conductivity channels in atmosphere, controlled by laser spark: pulsed sub-microsecond gas and chemical lasers (CO2, DF) and short pulse solid-state and UV lasers. Main advantage of short pulse lasers is their ability in forming of superlong ionised channels with a characteristic diameter of ~ 100 mkm in atmosphere along the beam propagation direction. At estimated electron densities below 1016 cm-3 in these filaments and laser wavelengths in the range of 0.5 - 1.0 mm, the plasma barely absorbs laser radiation. In this case, the length of the track composed of many filaments is determined by the laser intensity and may reach many kilometers at a femtosecond pulse energy of ~ 100 mJ. However, these lasers could not be used to form high-conductivity long channels in atmosphere. The ohmic resistance of this type a conducting channels turned out to be very high, and the gas in the channels could not be strongly heated (< 1 J). An electric breakdown controlled by radiation of femtosecond solid-state laser was implemented in only at a length of 3 m with a voltage of 2 MV across the discharge gap (670 kV/m). Not so long ago scientific group from P.N. Lebedev has improved that result, the discharge gap -1m had been broken under KrF laser irradiation when switching high-voltage (up to 390 kV/m) electric discharge by 100-ns UV pulses. Our previous result - 16 m long conducting channel controlled by a laser spark at the voltage - 3 MV - was obtained more than 20years ago in Russia and Japan by using pulsed CO2 laser with energy - 0.5 kJ. An average electric field strength was < 190 kV/m. It is still too much for efficient applications.

  17. Survey of laser injury

    NASA Astrophysics Data System (ADS)

    Johnson, Thomas E.; Dunn, J. C., II; Roach, William P.

    2002-06-01

    Laser use is pervasive and steadily expanding both in the private sector and the Department of Defense (DoD). For more than 20 years, Rockwell Laser Industries, the U.S. Army, and the Food and Drug Administration's Center for Devices and Radiological Health have separately collected data on injuries occurring during, or resultant from, the use of lasers. However, data from these sources is incomplete and has not recently undergone a thorough compiling, statistical analysis, review and summarization. It is our belief that in order to evaluate current related medical surveillance, safety and training procedures, this data needs such an examination. Persons maintaining these databases were contacted and any available data on laser injury was collected. The data was analyzed and examined for pertinent similarities and differences among a wide range of parameters. We summarize these findings in this paper and also comment on the injuries, current safety measures and injury reporting protocols associated with laser use.

  18. Auricular Acupuncture with Laser

    PubMed Central

    Bahr, Frank

    2013-01-01

    Auricular acupuncture is a method which has been successfully used in various fields of medicine especially in the treatment of pain relief. The introduction of lasers especially low-level lasers into medicine brought besides the already existing stimulation with needles and electricity an additional technique to auricular acupuncture. This literature research looks at the historical background, the development and the anatomical and neurological aspects of auricular acupuncture in general and auricular laser acupuncture in detail. Preliminary scientific findings on auricular acupuncture with laser have been described in detail and discussed critically in this review article. The results of the studies have shown evidence of the effect of auricular laser acupuncture. However, a comparison of these studies was impossible due to their different study designs. The most important technical as well as study parameters were described in detail in order to give more sufficient evidence and to improve the quality of future studies. PMID:23935695

  19. Laser-Atomic Oscillator

    NASA Astrophysics Data System (ADS)

    Jau, Yuan-Yu; Happer, William

    2008-05-01

    We report a newly developed technique, laser-atomic oscillator, for simultaneously generating stable optical and electrical modulations with a very few components. It requires only a semiconductor laser, a vapor cell, and a few optical components. No photodetector and electronic feedback are needed. In this new system, the ground-state hyperfine coherence of alkali-metal atoms is spontaneously generated. The modulated laser light with a spectrum of a small optical comb is automatically produced, and the spacing between the comb peaks is photonically locked to the hyperfine frequency. The charge carriers in the semiconductor laser are also modulated at the hyperfine frequency. Laser-atomic oscillator is purely optical. Its simple structure allows the system to be very compact. We believe this new technique will bring some advantages in the applications of atomic chronometry, atomic magnetometry, and generation of multi-coherent light.

  20. Solid State Laser

    NASA Technical Reports Server (NTRS)

    1990-01-01

    The Titan-CW Ti:sapphire (titanium-doped sapphire) tunable laser is an innovation in solid-state laser technology jointly developed by the Research and Solid State Laser Divisions of Schwartz Electro-optics, Inc. (SEO). SEO is producing the laser for the commercial market, an outgrowth of a program sponsored by Langley Research Center to develop Ti:sapphire technology for space use. SEO's Titan-CW series of Ti:sapphire tunable lasers have applicability in analytical equipment designed for qualitative analysis of carbohydrates and proteins, structural analysis of water, starch/sugar analyses, and measurements of salt in meat. Further applications are expected in semiconductor manufacture, in medicine for diagnosis and therapy, and in biochemistry.

  1. Laser driven radiography

    SciTech Connect

    Perry, M.D.; Sefcik, J.; Cowan, T.

    1997-12-20

    Intense laser (> 1021 W/cm{sup 3}) driven hard x-ray sources offer a new alternative to conventional electron accelerator Bremsstrahlung sources. These laser driven sources offer considerable simplicity in design and potential cost advantage for multiple axis views. High spatial and temporal resolution is achievable as a result of the very small source size (<100 um) and short-duration of the laser pulse. We have begun a series of experiments with the Petawatt laser at LLNL to determine the photon flux achievable with these sources and assess their potential for Stewardship applications. Additionally, we are developing a conceptual design and cost estimate of a multi-pulse, multi-axis (up to five) radiographic facility utilizing the Contained Firing Facility at site 300 and existing laser hardware.

  2. Guest Editorial: Laser Damage

    SciTech Connect

    Vitaly Gruzdev, Michelle D. Shinn

    2012-12-01

    Laser damage of optical materials, first reported in 1964, continues to limit the output energy and power of pulsed and continuous-wave laser systems. In spite of some 48 years of research in this area, interest from the international laser community to laser damage issues remains at a very high level and does not show any sign of decreasing. Moreover, it grows with the development of novel laser systems, for example, ultrafast and short-wavelength lasers that involve new damage effects and specific mechanisms not studied before. This interest is evident from the high level of attendance and presentations at the annual SPIE Laser Damage Symposium (aka, Boulder Damage Symposium) that has been held in Boulder, Colorado, since 1969. This special section of Optical Engineering is the first one devoted to the entire field of laser damage rather than to a specific part. It is prepared in response to growing interest from the international laser-damage community. Some papers in this special section were presented at the Laser Damage Symposium; others were submitted in response to the general call for papers for this special section. The 18 papers compiled into this special section represent many sides of the broad field of laser-damage research. They consider theoretical studies of the fundamental mechanisms of laser damage including laser-driven electron dynamics in solids (O. Brenk and B. Rethfeld; A. Nikiforov, A. Epifanov, and S. Garnov; T. Apostolova et al.), modeling of propagation effects for ultrashort high-intensity laser pulses (J. Gulley), an overview of mechanisms of inclusion-induced damage (M. Koldunov and A. Manenkov), the formation of specific periodic ripples on a metal surface by femtosecond laser pulses (M. Ahsan and M. Lee), and the laser-plasma effects on damage in glass (Y. Li et al). Material characterization is represented by the papers devoted to accurate and reliable measurements of absorption with special emphasis on thin films (C. Mühlig and S

  3. Laser dividing apparatus

    DOEpatents

    English, Jr., R. Edward; Johnson, Steve A.

    1995-01-01

    A laser beam dividing apparatus (10) having a first beam splitter (14) with an aperture (16) therein positioned in the path of a laser beam (12) such that a portion of the laser beam (12) passes through the aperture (16) onto a second beam splitter (20) and a portion of the laser beam (12) impinges upon the first beam splitter (14). Both the first beam splitter (14) and the second beam splitter (20) are, optionally, made from a dichroic material such that a green component (24) of the laser beam (12) is reflected therefrom and a yellow component (26) is refracted therethrough. The first beam splitter (14) and the second beam splitter (20) further each have a plurality of facets (22) such that the components (24, 26) are reflected and refracted in a number equaling the number of facets (22).

  4. Advances in chemical lasers

    SciTech Connect

    Miller, D.J.

    1987-09-25

    High-power chemical lasers thrive in an array of special environments and present many fascinating associated subjects ripe for developmental research. Included are processes to produce the source reactants; supersonic mixing and reacting flow fields; the production and dissipation of multiple vibrational-rotational molecular states; optical gain extraction in complex geometries; media inhomogeneity effects, and waste energy and reaction products removal. Some configurations require wavelength selectivity, special optical components, and coherent cavity or beam combining. In recent years, progress has been made in these areas on behalf of continuous-wave and repetitively pulsed hydrogen fluoride and deuterium fluoride lasers, subsonic and supersonic oxygen-iodine lasers, and potential shorter wavelength chemical lasers based on chemically excited higher electronic states. This paper presents a brief review of the technical approach of some of the technology areas, and the status in achieving practical, integrated high-power chemical lasers.

  5. Laser controlled flame stabilization

    DOEpatents

    Early, James W.; Thomas, Matthew E.

    2001-01-01

    A method and apparatus is provided for initiating and stabilizing fuel combustion in applications such as gas turbine electrical power generating engines and jet turbine engines where it is desired to burn lean fuel/air mixtures which produce lower amounts of NO.sub.x. A laser induced spark is propagated at a distance from the fuel nozzle with the laser ignitor being remotely located from the high temperature environment of the combustion chamber. A laser initiating spark generated by focusing high peak power laser light to a sufficiently tight laser spot within the fuel to cause the ionization of air and fuel into a plasma is unobtrusive to the flow dynamics of the combustion chamber of a fuel injector, thereby facilitating whatever advantage can be taken of flow dynamics in the design of the fuel injector.

  6. Laser-heated thruster

    NASA Technical Reports Server (NTRS)

    Kemp, N. H.; Krech, R. H.

    1980-01-01

    The development of computer codes for the thrust chamber of a rocket of which the propellant gas is heated by a CW laser beam was investigated. The following results are presented: (1) simplified models of laser heated thrusters for approximate parametric studies and performance mapping; (3) computer programs for thrust chamber design; and (3) shock tube experiment to measure absorption coefficients. Two thrust chamber design programs are outlined: (1) for seeded hydrogen, with both low temperature and high temperature seeds, which absorbs the laser radiation continuously, starting at the inlet gas temperature; and (2) for hydrogen seeded with cesium, in which a laser supported combustion wave stands near the gas inlet, and heats the gas up to a temperature at which the gas can absorb the laser energy.

  7. NASA Space Laser Technology

    NASA Technical Reports Server (NTRS)

    Krainak, Michael A.

    2015-01-01

    Over the next two decades, the number of space based laser missions for mapping, spectroscopy, remote sensing and other scientific investigations will increase several fold. The demand for high wall-plug efficiency, low noise, narrow linewidth laser systems to meet different systems requirements that can reliably operate over the life of a mission will be high. The general trends will be for spatial quality very close to the diffraction limit, improved spectral performance, increased wall-plug efficiency and multi-beam processing. Improved spectral performance will include narrower spectral width (very near the transform limit), increased wavelength stability and or tuning (depending on application) and lasers reaching a wider range of wavelengths stretching into the mid-infrared and the near ultraviolet. We are actively developing high efficiency laser transmitter and high-sensitivity laser receiver systems that are suitable for spaceborne applications.

  8. Ultrafast laser IR countermeasures

    NASA Astrophysics Data System (ADS)

    Rafailov, Michael K.

    2009-05-01

    Directional Infrared Countermeasures (DIRCM) is an effective technique to defeat heat-seeking missiles. The major problem of existing DIRCM is that it may work like a beacon for threats that are not susceptible to the jamming code implemented: attracting a missile instead of re-directing it away from the aircraft. Ultra-fast laser pulse technology is discussed as an alternative to a conventional laser DIRCM. An ultra-fast laser is capable of providing a different type of countermeasure which is compatible with existing laser based DIRCM pointing systems as it requires much less peak power than damage inducing systems. A foundation of ultra-fast technology is its unique ability to alter the intrinsic characteristics of the semiconductor. In this paper, we will only consider the effects of a mild lattice disturbance caused by relatively low energy ultra-fast (femto-second) and, to some extent, fast (pico-second) laser pulses.

  9. Laser space propulsion overview

    NASA Astrophysics Data System (ADS)

    Phipps, Claude; Luke, James; Helgeson, Wesley

    2007-05-01

    In this paper, we review the history of laser space propulsion from its earliest theoretical conceptions to modern practical applicatons. Applications begin with the "Lightcraft" flights of Myrabo and include practical thrusters for satellites now completing development as well as proposals for space debris removal and direct launch of payloads into orbit. We consider laser space propulsion in the most general sense, in which laser radiation is used to propel a vehicle in space. In this sense, the topic includes early proposals for pure photon propulsion, laser ablation propulsion, as well as propulsion using lasers to detonate a gas, expel a liquid, heat and expel a gas, or even to propagate power to a remote conventional electric thruster.

  10. Catalac free electron laser

    DOEpatents

    Brau, Charles A.; Swenson, Donald A.; Boyd, Jr., Thomas J.

    1982-01-01

    A catalac free electron laser using a rf linac (catalac) which acts as a catalyst to accelerate an electron beam in an initial pass through the catalac and decelerate the electron beam during a second pass through the catalac. During the second pass through the catalac, energy is extracted from the electron beam and transformed to energy of the accelerating fields of the catalac to increase efficiency of the device. Various embodiments disclose the use of post linacs to add electron beam energy extracted by the wiggler and the use of supplementary catalacs to extract energy at various energy peaks produced by the free electron laser wiggler to further enhance efficiency of the catalac free electron laser. The catalac free electron laser can be used in conjunction with a simple resonator, a ring resonator or as an amplifier in conjunction with a master oscillator laser.

  11. Catalac free electron laser

    DOEpatents

    Brau, C.A.; Swenson, D.A.; Boyd, T.J. Jr.

    1979-12-12

    A catalac free electron laser using a rf linac (catalac) which acts as a catalyst to accelerate an electron beam in an initial pass through the catalac and decelerate the electron beam during a second pass through the catalac is described. During the second pass through the catalac, energy is extracted from the electron beam and transformed to energy of the accelerating fields of the catalac to increase efficiency of the device. Various embodiments disclose the use of post linacs to add electron beam energy extracted by the wiggler and the use of supplementary catalacs to extract energy at various energy peaks produced by the free electron laser wiggler to further enhance efficiency of the catalac free electron laser. The catalac free electron laser can be used in conjunction with a simple resonator, a ring resonator, or as an amplifier in conjunction with a master oscillator laser.

  12. Free electron laser designs for laser amplification

    DOEpatents

    Prosnitz, Donald; Szoke, Abraham

    1985-01-01

    Method for laser beam amplification by means of free electron laser techniques. With wiggler magnetic field strength B.sub.w and wavelength .lambda..sub.w =2.pi./k.sub.w regarded as variable parameters, the method(s) impose conditions such as substantial constancy of B.sub.w /k.sub.w or k.sub.w or B.sub.w and k.sub.w (alternating), coupled with a choice of either constant resonant phase angle or programmed phase space "bucket" area.

  13. Laser Safety Inspection Criteria

    SciTech Connect

    Barat, K

    2005-06-13

    A responsibility of the Laser Safety Officer (LSO) is to perform laser audits. The American National Standard Z136.1 Safe Use of Lasers references this requirement through several sections. One such reference is Section 1.3.2.8, Safety Features Audits, ''The LSO shall ensure that the safety features of the laser installation facilities and laser equipment are audited periodically to assure proper operation''. The composition, frequency and rigor of that inspection/audit rests in the hands of the LSO. A common practice for institutions is to develop laser audit checklists or survey forms It is common for audit findings from one inspector or inspection to the next to vary even when reviewing the same material. How often has one heard a comment, ''well this area has been inspected several times over the years and no one ever said this or that was a problem before''. A great number of audit items, and therefore findings, are subjective because they are based on the experience and interest of the auditor to particular items on the checklist. Beam block usage, to one set of eyes might be completely adequate, while to another, inadequate. In order to provide consistency, the Laser Safety Office of the National Ignition Facility Directorate has established criteria for a number of items found on the typical laser safety audit form. The criteria are distributed to laser users. It serves two broad purposes; first, it gives the user an expectation of what will be reviewed by an auditor. Second, it is an opportunity to explain audit items to the laser user and thus the reasons for some of these items, such as labelling of beam blocks.

  14. Laser cooling of solids

    NASA Astrophysics Data System (ADS)

    Nemova, Galina; Kashyap, Raman

    2010-08-01

    Laser cooling of solids, sometimes also known as optical refrigeration, is a fast developing area of optical science, investigating the interaction of light with condensed matter. Apart from being of fundamental scientific interest, this topic addresses a very important practical issue: design and construction of laser pumped solid-state cryocoolers, which are compact, free from mechanical vibrations, moving parts, fluids and can cause only low electromagnetic interference in the cooled area. The optical cryocooler has a broad area of applications such as in the development of magnetometers for geophysical sensors, in biomedical sensing and can be beneficial for satellite instrumentations and small sensors, where compactness and the lack of vibrations are very important. Simply, a laser cooler works on the conversion of low energy pump photons into high-energy anti-Stokes fluorescence photons by extracting some of the phonons (heat energy) in a material. That is, the process of laser cooling of solids is based on anti-Stokes fluorescence also known as luminescence upconversion, when light quanta in the red tail of the absorption spectrum are absorbed from a pump laser, and blue-shifted photons are spontaneously emitted. The extra energy extracted from the solid-state lattice in the form of the phonons is the quanta of vibrational energy which generates heat. The idea to cool solids with anti-Stokes fluorescence was proposed in 1929 by Peter Pringsheim and first demonstrated experimentally by Epstein's research team in 1995. In 1999, Steven Bowman proposed to use the optical refrigeration by anti-Stokes fluorescence within the laser medium to balance the heat generated by the Stokes shifted stimulated emission in a high-power solid-state bulk laser. Such a laser without internal heating named radiation-balanced or athermal laser was experimentally demonstrated for the first time in 2002. At the present time laser cooling of solids can be largely divided into three

  15. Consistency analysis on laser signal in laser guided weapon simulation

    NASA Astrophysics Data System (ADS)

    Yin, Ruiguang; Zhang, Wenpan; Guo, Hao; Gan, Lin

    2015-10-01

    The hardware-in-the-loop simulation is widely used in laser semi-active guidance weapon experiments, the authenticity of the laser guidance signal is the key problem of reliability. In order to evaluate the consistency of the laser guidance signal, this paper analyzes the angle of sight, laser energy density, laser spot size, atmospheric back scattering, sun radiation and SNR by comparing the different working state between actual condition and hardware-in-the-loop simulation. Based on measured data, mathematical simulation and optical simulation result, laser guidance signal effects on laser seeker are determined. By using Monte Carlo method, the laser guided weapon trajectory and impact point distribution are obtained, the influence of the systematic error are analyzed. In conclusion it is pointed out that the difference between simulation system and actual system has little influence in normal guidance, has great effect on laser jamming. The research is helpful to design and evaluation of laser guided weapon simulation.

  16. Frequency stabilization of diode-laser-pumped solid state lasers

    NASA Technical Reports Server (NTRS)

    Byer, Robert L.

    1988-01-01

    The goal of the NASA Sunlite program is to fly two diode-laser-pumped solid-state lasers on the space shuttle and while doing so to perform a measurement of their frequency stability and temporal coherence. These measurements will be made by combining the outputs of the two lasers on an optical radiation detector and spectrally analyzing the beat note. Diode-laser-pumped solid-state lasers have several characteristics that will make them useful in space borne experiments. First, this laser has high electrical efficiency. Second, it is of a technology that enables scaling to higher powers in the future. Third, the laser can be made extremely reliable, which is crucial for many space based applications. Fourth, they are frequency and amplitude stable and have high temporal coherence. Diode-laser-pumped solid-state lasers are inherently efficient. Recent results have shown 59 percent slope efficiency for a diode-laser-pumped solid-state laser. As for reliability, the laser proposed should be capable of continuous operation. This is possible because the diode lasers can be remote from the solid state gain medium by coupling through optical fibers. Diode lasers are constructed with optical detectors for monitoring their output power built into their mounting case. A computer can actively monitor the output of each diode laser. If it sees any variation in the output power that might indicate a problem, the computer can turn off that diode laser and turn on a backup diode laser. As for stability requirements, it is now generally believed that any laser can be stabilized if the laser has a frequency actuator capable of tuning the laser frequency as far as it is likely to drift in a measurement time.

  17. Laser Transmitter Design for the Geoscience Laser Altimeter System

    NASA Technical Reports Server (NTRS)

    Afzal, R. S.; Yu, A. W.; Mamakos, W.; Lukemire, A.; Dallas, J. L.; Schroeder, B.; Green, J. W.

    1998-01-01

    NASA is embarking on a new era of laser remote sensing instruments from space. This paper focuses specifically on the laser technology involved in one of the present NASA missions. The Geoscience Laser Altimeter System (GLAS) scheduled to launch in 2001 is a laser altimeter and lidar for the Earth Observing System's (EOS) ICESat mission. The laser transmitter for this space-based remote sensing instrument is discussed in the context of the mission requirements.

  18. Laser Propulsion Standardization Issues

    SciTech Connect

    Scharring, Stefan; Eckel, Hans-Albert; Roeser, Hans-Peter; Sinko, John E.; Sasoh, Akihiro

    2010-10-08

    It is a relevant issue in the research on laser propulsion that experimental results are treated seriously and that meaningful scientific comparison is possible between groups using different equipment and measurement techniques. However, critical aspects of experimental measurements are sparsely addressed in the literature. In addition, few studies so far have the benefit of independent confirmation by other laser propulsion groups. In this paper, we recommend several approaches towards standardization of published laser propulsion experiments. Such standards are particularly important for the measurement of laser ablation pulse energy, laser spot area, imparted impulse or thrust, and mass removal during ablation. Related examples are presented from experiences of an actual scientific cooperation between NU and DLR. On the basis of a given standardization, researchers may better understand and contribute their findings more clearly in the future, and compare those findings confidently with those already published in the laser propulsion literature. Relevant ISO standards are analyzed, and revised formats are recommended for application to laser propulsion studies.

  19. Lasers in digestive endoscopy

    NASA Astrophysics Data System (ADS)

    Brunetaud, Jean Marc; Maunoury, Vincent; Cochelard, Dominique

    1997-01-01

    Lasers were introduced in digestive endoscopy to stop active gastroduodenal hemorrhages. Their use spread progressively to the treatment of chronic hemorrhages from vascular malformations and sessile tumors. Laser face competition from other endoscopic techniques such as electrocoagulation, injection techniques, dilation, stents, and brachytherapy. Many series have reported the efficacy of lasers in digestive endoscopy used for their thermal or photochemical effects. However, they were gradually abandoned for the treatment of hemorrhages because of competition from nonlaser techniques. Lasers are still used for ablation of sessile tumors, but their true impact is difficult to evaluate. Modern methods of technology assessment did not allow gastroenterologists to clearly define the place of lasers among surgery, radio-chemotherapy, and other endoscopic techniques, and data on the daily use of lasers are not available. Therefore, the conclusion can only be subjective. The best current application of thermal lasers appears to be in the treatment of rectosigmoid villous adenomas in elderly patients. Small superficial rectal cancers may also become a good subject due to the impact of endoscopic ultrasonography. Early lesions with multifocal or diffuse disease such as early esophageal cancers could be the most promising subject of application for photodynamic therapy in the future.

  20. Excimer laser photoresist stripping

    NASA Astrophysics Data System (ADS)

    Genut, Menachem; Tehar-Zahav, Ofer; Iskevitch, Eli; Livshits, Boris

    1996-06-01

    A new method for stripping the most challenging photoresists on deep sub-micron technology semiconductor wafers has been developed. The method uses a combination of UV excimer laser ablation and reactive chemistry to strip the photoresist in a single dry process, eliminating the wet acids or solvents often used following ashing of high dose implantation (HDI) and reactive ion etching (RIE). The stripping process combines new removal mechanisms: chemical assisted UV excimer laser ablation/etching, laser induced chemical etching of side walls and residues, and enhanced combustion. During the laser pulses photolysis of the process gas occurs, UV laser radiation breaks the photoresist polymer chain bonds, and the photoresist (including foreign materials imbedded in it) is ablated. The combustion is ignited by the ablative impact of laser radiation and enhanced by the radicals formed during photo-thermal decomposition of the process gases. Following this process, the volatilized products and gases are evacuated. The optimum laser stripping conditions were developed to provide a wide process window for the most challenging stripping conditions, such as after HDI and RIE (metal, polysilicon), without causing damage to the wafer devices. A photoresist stripping system based on the described technology was designed and built. The system has been designated as the L-StripperTM and provides stripping time of 0.15 s/(micrometer cm2).