bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of 830 nm continuous wave laser diode irradiation on median nerve function in normal subjects
Authors: Basford J. R. , Hallman H. O. , Matsumoto J. Y. , Moyer S. K. , Buss J. M. , Baxter G. D.
Published: March 2007

The presence, magnitude, and nature of the effect that low intensity laser irradiation has on nerve function, growth, and repair constitute a contentious area of research. We have addressed one aspect of this controversy by systematically examining the influence of 830 nm laser radiation on median nerve function. In particular, we investigated median nerve motor and sensory distal latencies, action potential amplitudes, action potential areas, and conduction velocities as well as dorsal hand skin temperatures in 33 normal subjects in a double‐blinded, randomized controlled study. All subjects received identical treatment: 30 seconds of “irradiation” at 10 points over the course of the right median nerve (five sites on the forearm and five sites distal to the wrist crease) with either an active (1.2 J/point) or inactive (0 J/point) 40 mW 830 nm continuous wave IR laser diode. Latencies, conduction velocities, amplitudes, areas, and skin temperatures were collected bilaterally at a baseline immediately prior to irradiation and at intervals of 1, 5, 10, 15, 20, and 30 minutes following treatment. Analysis of the results reveals that motor and sensory distal latencies were decreased in the treated limbs of the lasertreated group relative to the control group by 3–4% (P <.016 and.046, respectively, rank sum test). No significant differences in these quantities were found between the limbs within either group. Similarly, no alterations of action potential amplitudes, action potential areas, forearm conduction velocities, or skin temperatures were detected within or between the groups. Thus on the basis of this experiment, percutaneous 830 nm continuous wave laser irradiation can affect median nerve function, but the effects are quite limited and appear to be limited to the distal portion of the nerve. © 1993 Wiley‐Liss, Inc.
Study of the fluorescence properties of normal and neoplastic human cervical tissue
Authors: Mahadevan Anita , Mitchell Michele Follen , Silva Elvio , Thomsen Sharon , Richards‐Kortum Rebecca R.
Published: March 2007

Fluorescence excitation‐emission matrices (EEMs) were obtained in vitro for 18 cervical biopsies from 10 patients. At all excitation emission maxima, but especially at 330 nm excitation, 385 nm emission, the average normalized fluorescence intensity of histologically normal tissue is greater statistically than that of histologically abnormal tissue. A diagnostic algorithm based on the relative intensity at 330 nm excitation, 385 nm emission can differentiate histologically normal and abnormal biopsies with a higher sensitivity (89%), but a lower positive predictive value (67%) and specificity (44%) than colposcopy (78%, 88%, 89%, respectively). However, paired comparison of histologically normal and abnormal biopsies from the same patient results in a sensitivity of 75%, positive predictive value of 86% and specificity of 88% for spectroscopic identification of histologic abnormality similar to that of colposcopy. This pilot study indicates that fluorescence spectroscopy may be useful in differentiating normal and abnormal tissue; based on these results, a strategy for in vivo studies is discussed. © 1993 Wiley‐Liss, Inc.
Partial nephrectomy with a combined CO2 and Nd:YAG laser: Experimental study in pigs
Authors: Taari Kimmo , Salo Jaakko O. , Rannikko Sakari , Nordling Stig
Published: March 2007

Twenty‐eight partial nephrectomies were performed on nine pigs with a simultaneous, coaxial CO2‐Nd:YAG laser at power settings of 20 W and 40 W, or with a steel scalpel. A vascular pedicle clamp was used without renal cooling. The time for hemostasis was 4.5 ± 3.2 min (mean ± SD) with the laser and 6.4 ± 2.5 min with the steel scalpel (P = 0.064). There was no difference in the total operation time (10.4 ± 3.5 min with the laser vs. 11.0 ± 3.2 min with the steel scalpel, P = 0.470). The mean blood loss with the laser was 17.5 ± 6.7 g and 22.1 ± 15.2 g with the steel scalpel (P = 0.299). The number of ligatures needed for complete hemostasis was 2.9 ± 2.1 with the laser and 5.0 ± 2.3 with the steel scalpel (P = 0.011). The average thermal damage was 0.23 ± 0.10 mm. It is concluded that the simultaneous CO2‐Nd:YAG laser method can be used in partial nephrectomy and it offers better hemostasis than the conventional technique. Further studies with different power levels are needed. © 1994 Wiley‐Liss, Inc.
Endoscopic neodymium: YAG laser treatment of radiation‐induced hemorrhagic cystitis
Authors: Ravi R.
Published: March 2007

Hemorrhagic cystitis is a debilitating complication of radiation therapy for pelvic malignancy. Forty‐two such patients with intractable hematuria underwent endoscopic Nd:YAG laser coagulation under local anesthesia between January 1990 and July 1992. The laser power was kept at ⩽ 30 W and the pulse duration ⩽ 3 s. Control of bleeding was achieved in 39 patients after one sitting and in 2 patients after two sittings of laser treatment. There were no complications of the procedure and recurrence of bleeding was not seen in any of the patients achieving CR at a mean follow‐up period of 14 months. With modifications in the safety guidelines, we recommend laser treatment as the initial procedure of choice in patients with hemorrhagic radiation Cystitis. © 1994 Wiley‐Liss, Inc.
CO2 laser subcapsular orchidectomy in the treatment of metastatic prostate cancer
Authors: Bolton Damien M. , Costello Anthony J.
Published: March 2007

Hormonal manipulation remains the main method of treatment in metastatic carcinoma of the prostate. Traditional techniques of surgical castration may result in complications due to bleeding within the scrotum. Because of its cutting and hemostatic properties, superior to that seen with traditional scalpel incisions in vessels < 1.5 mm diameter [1,2], the carbon dioxide laser has been used in performing subcapsular orchidectomy in an attempt to reduce such complications. Postoperative hormonal assays have demonstrated a response identical to orchidectomy, and no treatment complications were encountered in our series. Subcapsular orchidectomy using the carbon dioxide laser may offer an advantage over traditional methods of surgical castration by reducing the frequency of postoperative hematoma. © 1994 Wiley‐Liss, Inc.
Tumor growth delay by laser‐generated shock waves
Authors: de Reijke Theo M. , Schamhart Denis H. , Kurth Karl‐Heinz , Löwik Clemens W. , Donkers Laurens H. , Sterenborg Henricus J.
Published: March 2007

The antiproliferative effect of laser‐generated shock waves (LSW) was investigated on a human renal cell carcinoma, RC‐8, grown subcutaneously in the nu/nu mouse. The RC‐8 is characterized by the syndrome of humoral hypercalcemia of malignancy (HHM) associated with profound cachexia, increase of serum Ca level, hypophosphatemia, and an enhancement of serum parathyroid‐like peptides. In this model system, the effects on cachexia and tumor growth were studied after a series of pulses (3–200) generated by a Candela LFDL/3 equipped pulsed‐dye laser with optical fiber guided through a hypodermic needle with a 45° angle bended tip, stuck through the skin of the mouse, and positioned directly below the tumor. The antitumor effect, expressed as a delay of tumor growth, was found to be dependent on number of pulses applied, tumor size, and growth rate (α). Treatment of RC‐8 with α = 0.21 was effective only after 200 pulses combined with a tumor volume smaller than 100 mm3. Under these conditions a growth delay of ∼8 days was observed, paralleled by delay of animal weight loss (cachexia). Under conditions of a decreased growth rate of RC‐8 (α = 0.13), the susceptibility toward L‐SW was found to be increased, expressed by a suppression of tumor growth after 100 pulses. However, no L‐SW‐associated delay of cachexia was observed under these latter conditions. © 1994 Wiley‐Liss, Inc.
Phthalocyanine photodynamic therapy: New strategy for closure of choroidal neovascularization
Authors: Kliman Gilbert H. , Puliafito Carmen A. , Stern David , Borirakchanyavat Sidhiporn , Gregory William A.
Published: March 2007

Chloro‐aluminum sulfonated phthalocyanine (CASPc) is a photo‐chemically active dye employed in photodynamic therapy (PDT). CASPc is a potent generator of singlet oxygen when irradiated with 675 nm light and is also capable of fluorescence, allowing visualization of the dye in tissues. We devised an angiography system using CASPc fluorescence to determine its localization in experimental choroidal neovascularization in monkeys and then investigated the ability of CASPc to produce photochemical closure of neovascularization upon irradiation with 675nm laser light. Fluorescent imaging indicated that CASPc localized angio‐graphically in areas of neovascularization for at least 24 hours. Irradiation with 675 nm laser light 5–30 minutes after CASPc injection produced complete closure of choroidal neovascularization with minimal damage to overlying retina. We conclude that CASPc localizes in neovascular choroidal vessels and that CASPc photodynamic therapy can produce closure of these choroidal vessels. © 1994 Wiley‐Liss, Inc.
Phthalocyanine mediated photodynamic thrombosis of experimental corneal neovascularization: Effect of phthalocyanine dose and irradiation onset time on vascular occlusion rate
Authors: Tsilimbaris Miltiadis K. , Pallikaris Ioannis G. , Naoumidi Irini I. , Vlahonikolis Ioannis G. , Tsakalof Andreas K. , Lydataki Stella E.
Published: March 2007

The aim of this study was to evaluate the possible influence of phthalocyanine dose and of time interval between phthalocyanine injection and irradiation commencement on the rate of experimental corneal neovascularization photodynamic thrombosis in albino rabbits. New corneal vessels were irradiated with a diode laser (670 nm, 2 mW) after the intravenous injection of chloroaluminum sulfonated phthalocyanine. Different animals were irradiated either 5 min after the injection of different phthalocyanine doses (3, 6, 8, 12, or 14 mg/kg), or at different times (5 min, 24 h, or 58 h) after a standard phthalocyanine dose (3 mg/kg) injection. Irradiation time necessary for vascular occlusion was recorded. Decrease of phthalocyanine dose as well as delay of irradiation onset resulted in a statistically significant increase of irradiation time. Electron and light histological examination revealed platelet thrombi inside irradiated corneal new vessels. Damage in the vascular endothelial cell membrane and in intercellular contact structure was noted, leading to disorganization of the endothelial cells layer and death of most endothelial cells. These results indicate that both early commencement of irradiation after phthalocyanine injection and phthalocyanine dose increase accelerate the rate of phthalocyanine mediated corneal neovascularization photodynamic thrombosis. Thrombosis seems to result from photochemically induced vascular endothelial cell damage. © 1994 Wiley‐Liss, Inc.
Continuous measurement of the heat‐induced changes in the optical properties (at 1,064 nm) of rat liver
Authors: Pickering John W. , Posthumus Paul , van Gemert Martin J. C.
Published: March 2007

The radiative transfer optical properties (absorption coefficient, scattering coefficient, and anisotropy of scattering) of slowly heated rat liver have been measured at 1,064 nm. Continuous measurements were made using double‐integrating spheres and collimated illumination of the sample for up to 5,000 seconds heating with equilibrium temperatures of 48°, 52°, and 58°C. Generally, the scattering increased, and the absorption and anistropy decreased at rates dependent on the heating temperatures. However, there was a large variability between samples. © 1994 Wiley‐Liss, Inc.
SEM comparison of acid‐etched, co2 laser‐irradiated, and combined treatment on dentin surfaces
Authors: Silberman Jaime J. , Dederich Douglas N. , Vargas Marcos , Denehy Gerald E.
Published: March 2007

Research into polymer systems capable of bonding to dentin and enamel have resulted in improved bond strengths that allow more conservative restoration and strengthening of teeth. However, pretreatment of the dentin and enamel of various sorts, including exposure to laser energy, have been espoused to enhance this bonding. This study investigated the effects of two pretreatments, acid and CO2 laser exposure, both alone and in combination, on the surface topography of prepared dentin specimens as observed by scanning electron microscopy. Eighteen dentin specimens were flat‐sanded with 600 grit sandpaper and exposed to 10% maleic acid and CO2 laser both alone and in combination. SEM observation suggested that laser treatment prior to acid etching could increase the resistance of the smear layer to acid removal, that laser exposure after acid treatment could expose a porous topography suggestive of the underlying dentin inorganic structure by way of vaporization of the collagen surface left after acid demineralization, and that these effects varied in degree with the laser exposure energy. © 1994 Wiley‐Liss, Inc.
Beam profile of the flashlamp pumped pulsed dye laser: Support for overlap of exposure spots
Authors: Dinehart Scott M. , Flock Stephen , Waner Milton
Published: March 2007

The degree to which individual practitioners overlap exposure spots of the flashlamp pumped pulsed dye laser when treating large vascular lesions appears to be a matter of personal preference. There are few data to support one approach over another. We have measured the beam profile of this laser at two different energy fluences using a photodiode and a digitizing storage oscilloscope. Results show that for each energy fluence, the beam intensity decreases from the center to the outside rim of the beam. A plot of beam intensity versus the radius of the treatment field approaches a truncated normal distribution with a full width at half‐maximum of 4.7–4.8 mm. These results help explain why clinical overlap of exposure spots can be safely undertaken and provide a rationale for recommendations concerning the degree of overlap needed to expedite treatment while still minimizing adverse reactions. © 1994 Wiley‐Liss, Inc.
Effects of nimodipine and dexamethasone on low‐level co2 laser‐induced release of 51chromium from canine 2c5 gliosarcoma cells
Authors: van Kooten David W. , Maciunas Robert J. , Carver Robert S.
Published: March 2007

Low‐energy penumbral irradiation of surgical lasers may produce undesirable effects on surrounding tissues. This study used a 51Cr cell labeling technique to determine if gliosarcoma cells could be therapeutically protected prior to their exposure to low‐power laser irradiation. Canine 2C5 gliosarcoma cells with intra‐cellular 51Cr were treated with nimodipine and/or dexamethasone and then exposed to low‐power levels of CO2 laser. The 51Cr was released from the cells in a dose‐dependent fashion following exposure to laser energy. Correlative analysis of the data indicated that a strong direct relationship between laser fluence and 51Cr release did exist for controls and drug‐treated groups with coefficients of correlation r ≥ +0.90 and coefficients of determination r2 ≥ 0.82. However, comparison of the data from the drug‐treated and control groups found that there was no significant difference between them (P >.05). Therefore, no protective or detrimental effects were observed with the use of nimodipine and/or dexamethasone on the gliosarcoma cells as tested in this system. Further investigation is necessary in order to define the mechanisms by which low‐power level lasers affect these cells. These effects do not appear to be mediated through localization of mechanisms to the cell membranes or their constituent Ca2+channels. © 1994 Wiley‐Liss, Inc.
Pulsed Ho:YAG laser meniscectomy: Effect of pulsewidth on tissue penetration rate and lateral thermal damage
Authors: Vangsness C. Thomas , Watson Troy , Saadatmanesh Vahid , Moran Kevin
Published: March 2007

Background and Objective: Studies need to define the optimal parameters under which the holmium laser should operate for arthroscopic meniscectomy. This study was designed to analyze the effect of various Holmium wavelength pulsewidths on human meniscal tissue penetration rates and lateral thermal injury.

Study Design/Materials and Methods: Using a pulsed Holmium: YAG laser at a wavelength of 2.1μm, the effect of various pulsewidths on tissue penetration rates as well as the degree of accompanying thermal damage in human meniscal tissue was evaluated in a specially designed jig. Holding the energy constant at 500 mJ per pulse, the pulsewidth was varied between 100 and 600 microseconds.

Results: Fiber penetration of meniscal tissue was found to be fastest at a pulsewidth of 250 microseconds. As the pulsewidth was increased or decreased around this number, the observed penetration time decreased, although no statistical difference was found. The size of the hole created was inversely related to the penetration time. Microscopic examination revealed zones of lateral thermal effect extending 800 μm from the ablation site.

Conclusion: No relationship between the pulsewidth and the lateral thermal effect could be found. © 1995 Wiley‐Liss, Inc.
Characteristics of Nd:YAG sculptured contact probes after prolonged laser application
Authors: Barroso Eduardo G. , Haklin Michael F. , Staren Edgar D.
Published: March 2007

This study analyzed the functional and structural characteristics of cone, hemisphere, and modified sculptured contact fibers (1,000 μm) after 1 hour of continuous Nd:YAG laser application. Continuous laser application was performed on live porcine tissue using 20 watts of power. The fiber's appearance under a microscope as well as the power output was recorded after 0, 5, 10, 20, 30, 45, and 60 minutes of continuous laser application. (N = 3 for each fiber). At time 0, all fibers transmitted from 49 to 56% of the initial 20 watts (W); power transmission decreased to less than 9% relative power transmission after 20 minutes and then plateaued. The fibers exhibited severe distortion and carbonization of the surface where laser had been applied with evidence of quartz melting and shattering after only 10 minutes. By 30 minutes of laser application, all three fibers were fractured and essentially indistinguishable from one another; moreover, the fibers exhibited similar power transmission, and cutting and coagulation activity, as determined by a panel of independent, double‐blinded surgeons. These data lead us to conclude that 1) Nd:YAG contact laser effects result from thermal heating of the fiber tip with subsequent tissue injury, 2) the unique structural configuration of the fiber's sculptured tip are lost after several minutes of laser application without appreciable change in functional integrity, and 3) fibers may be manually fractured allowing for multiple uses without significant sacrifice of power transmission or surgical utility. © 1995 Wiley‐Liss, Inc.
Fragmentation process of current laser lithotriptors
Authors: Rink Klaus , Delacrétaz Guy , Salathé René P.
Published: March 2007

Background and Objective: Flashlamp pumped dye (FPDL), Q‐switched Nd:YAG, and alexandrite lasers are the most clinically used laser lithotriptors. Although calculi are fragmented by laser induced mechanical stresses for all lithotriptors, different fragment sizes and fragmentation efficiencies have been reported. In this work the effect of the pulse duration and pulse shape on the fragmentation processes is studied.

Material and Methods: Fragmentation processes are characterized on model stones and on sensing target fibers. Stone fragmentation and cavitation bubble generation are observed by video flash photography. Shock wave occurrence and strength are monitored with an hydrophone.

Results: For the FPDL, stone fragmentation is induced by the collapse of the large cavitation bubble formed. For the Q‐switched Nd:YAG, fragmentation is already observed during the laser pulse, at the plasma onset, although further fragmentation can occur at the bubble collapse. For pulse durations corresponding to the alexandrite, an intermediate fragmentation regime is observed.

Conclusion: For the first time the physical basis of the observed differences in the fragmentation efficiencies of current laser lithotriptors is described. For nanosecond durations the fragmentation processes are governed by plasma induced shock waves. On the contrary, for microsecond durations fragmentation is governed by cavitation. The high fragmentation efficiency of microsecond lasers is due to a high laser energy transfer into cavitation. © 1995 Wiley‐Liss, Inc.
Optical properties of human articular tissue as implication for a selective laser application in arthroscopic surgery
Authors: Raunest Juergen , Schwarzmaier Hans‐Joachim
Published: March 2007

Background and Objective: Optical density of normal and pathological hyaline cartilage, meniscus, and synovium is determined using native and laser‐irradiated tissue samples in order to examine potentials for a selective laser ablation.

Study Design/Materials and Methods: One hundred forty‐four autopsy specimens were irradiated in a direct contact mode using a XeCl excimer laser (λ = 308 nm; 20 ns; 40 Hz; 40 ± 2.1 J/mm2; 800 μm fused silica fiber) and a continuous‐wave Nd:YAG laser (λ = 1,064 nm; 1 s; 124 ± 5.4 W/mm2; 600 μm fused silica fiber). Transmission spectra were obtained by microspectrophotometry in a spectral range from 250 to 770 nm.

Results: In the ultraviolet spectrum analyzed, optical density (OD) is calculated to 0.81 ± 0.05 for native hyaline cartilage, to 1.0 ± 0.07 for meniscal tissue, and to 0.68 ± 0.04 for synovium. With increasing wavelength the OD steadily decreases reaching mean values of 0.06 ± 0.01, 0.13 ± 0.03, and 0.15 ± 0.04 at 750 nm. Compared to normal tissue degeneration of cartilage and meniscus lead to a significant increase in OD with a maximum relative OD of 4.39 and 1.26, respectively (P <.001 and P <.01). In synovitis the OD increases with a maximum ratio of 1.45:1 (P <.01). Following Nd:YAG laser exposition the OD of the coagulated zone exceeded the value of native tissue by a factor of 9.71 for cartilage, 4.71 for meniscus, and 3.04 for synovium (P <.001). Excimer irradiation leads to a 3.38‐fold increase in OD for cartilage, 2.23‐fold for meniscal tissue, and 1.6‐fold for synovium (P <.01).

Conclusion: The results presented indicate that a preferential ablation of pathological tissue structures in articular surgery is possible by selecting laser systems with an appropriate spectral emission range. However, thermal laser tissue interaction may lead to severe alterations in optical properties reducing potentials of a preferential or selective laser application. © 1995 Wiley‐Liss, Inc.
Laparoscopic surgery of chronic hyperandrogenic anovulation
Authors: Kaaijk Eugenie M. , Beek Johan F. , van der Veen Fulco
Published: March 2007

The review describes briefly the clinical and endocrinological characteristics of chronic hyperandrogenic anovulation (CHA), as well as ovulation induction by hormone therapy (therapy of first choice) and by classical wedge resection. The main purpose of this study, however, is to compare different laparoscopic treatments of CHA, with emphasis on laser treatments by argon, CO2, Nd:YAG, and frequency‐doubled Nd:YAG laser. The overall results of laparoscopic treatments in hormone‐therapy–resistant patients with CHA are encouraging and the results are comparable. In the studies considered in this review, ovulation was induced for longer or shorter periods in 21 out of 31 patients (68%) after ovarian biopsy, in 57 out of 73 patients (78%) after electro‐surgery, and in 82 out of 118 patients (70%) after laser treatment. Subsequent conception occurred in 44%, 40%, and in 41% of the patients, respectively. Of interest is the fact that some hormone‐therapy–resistant patients become sensitive to Clomiphene after laparoscopic treatment, giving an overall percentage of ovulation and an overall pregnancy rate of 89% and 54%, respectively, for electrosurgery, and of 88% and 50%, respectively, for laser treatment. Unfortunately, adhesion formation, a serious complication of surgical treatment of the ovaries, is still a drawback using laparoscopic surgical techniques. © 1995 Wiley‐Liss, Inc.
Role of the alexandrite laser for removal of tattoos
Authors: Stafford Timothy J. , Lizek Robert , Tan Oon Tian
Published: March 2007

Background and Objective: The development of the Alexandrite laser for the removal of blue‐black tattoos is described.

Study Design/Materials and Methods: The responses of an animal study, using professionally tattooed skin and a human study involving 22 (professional and nonprofessional) blue‐black tattoos, to the Alexandrite laser are reported.

Results: Histopathologic evaluation of tattooed pig skin biopsies demonstrated the method of removal of dermal tattoo pigment. An average 11.6 treatments were required to remove completely the ten human blue‐black professional tattoos compared to an average of 10.3 treatments to reach the same endpoint in six subjects with nonprofessional tattoos.

Conclusion: Of significance was the fact that unlike the Q‐switched Ruby and Nd: YAG lasers where punctate bleeding and tissue splattering have been reported to occur during laser tattoo removal, epidermal integrity was maintained during exposure of tattooed skin to the Q‐switched Alexandrite laser at therapeutic fluences used. © 1995 Wiley‐Liss, Inc.
Superior nerve anastomosis using a low‐output CO2 laser on fibrin membrane
Authors: Ochi Mitsuo , Osedo Masashi , Ikuta Yoshikazu
Published: March 2007

Background and Objective: To date, no procedure of laser‐aided nerve anastomosis has yet proved to be consistently superior to suture nerve repair. This study examines a new method for nerve repair using a low output CO2 laser and fibrin membrane to ascertain the efficacy of this method for nerve regeneration in comparison with the suture method.

Study Design/Materials and Methods: Both sciatic nerves of 42 Wister rats were used. The left sciatic nerves were cut and reconnected using 70 mW of irradiation on fibrin membrane bridging the nerve stumps, whereas the right sciatic nerves were repaired with two stitches of epineuro‐fascicular sutures.

Results: No deleterious effect of the irradiation on nerve regeneration was demonstrated at any time after surgery. The number of myelinated axons larger than 5 μm in diameter and the mean diameter of mylinated axons 8 weeks after surgery were significantly larger in the laser group than those in the suture group (P < 0.05).

Conclusion: The results suggest this new method may be useful and effective for clinical nerve repair. © 1995 Wiley‐Liss, Inc.
Spot size reduction in coupling of laser to micromanipulator in laser microsurgery by fiberoptic link
Authors: Logunov Stephan L. , Lemberg Vladimir G.
Published: March 2007

Background and Objective: In coupling laser with micromanipulator through fiberoptics, the resulting diameter of the spot is limited by the laws of geometrical optics, because of the high numerical aperture (N.A.) of fiberoptic radiation. A new method for the reduction of spot size diameter is suggested.

Study Design/Materials and Methods: The output of a 2 mW He‐Ne laser was couped via fiberoptic link, the fiberoptic output light collected by a single lens collimator and directed to the input of the micromanipulator.

Results: The spot size can be considerably reduced by the introduction of an aperture which reduces the numerical aperture (N.A.) of the fiberoptic. The resulting reduction in total power has little effect on the power density.

Conclusion: This approach to the collimator design permits reduction in spot size without any significant changes in power density, thus avoiding damage to the tissue and obtaining optimum performance from the micromanipulator. © 1995 Wiley‐Liss, Inc.
Transurethral Balloon Laser Prostatectomy in the Canine: Medium‐Term, Follow‐Up Results
Authors: Suzuki Takanori , Kurokawa Kohei , Suzuki Kazuhiro , Yamanaka Hidetoshi
Published: March 2007

Background and Objective: To demonstrate surgical complications in transurethral balloon laser prostatectomy by medium‐term, follow‐up observation.

Study Design/Materials and Methods: Three dogs were treated with transurethral laser irradiation using 15 watts for 20 minutes at 60°C at a 5 mm depth of the prostate, one dog was for 5 minutes with same parameters, and one dog was with only laser balloon probe as a control. All animals were followed for 24 weeks.

Results: A large cavity in the prostatic urethra was formed in laser‐treated animals 4 weeks later, whereas the cavity in the balloon‐treated animals was not shown. Cavity volume did not significantly change for 6 months, and there was no bladder neck stricture or urethral stenosis observed in any case. An increase in collagen fibers in the periurethral tissue was barely observed by Mallory staining.

Conclusion: The risk of bladder neck stricture and urethral stenosis was estimated to be low for transurethral balloon laser prostatectomy. © 1995 Wiley‐Liss, Inc.
Transurethral Nd:YAG laser prostatectomy with a laterally firing fiber: Local effects on tissue associated with erectile dysfunction
Authors: Breza Jan , Aboseif Sherif , Zvara Peter , Bolton Damien , Tewari Ashutosh , Narayan Perinchery
Published: March 2007

Background and Objectives: Transurethral laser prostatectomy is anticipated to become a recognized alternative to conventional transurethral resection of the prostate. However, the effects of this procedure on the nerves of the pelvic plexus and erectile dysfunction remain unaddressed. The objective of this study was to evaluate the effects of laser energy on extent of prostatic damage as well as injury to periprostatic cavernosal nerves and erectile dysfunction in a canine model.

Study Design/Materials and Methods: Six adult male mongrel dogs underwent transurethral laser prostatectomy at 30 (n = 3) and 40 (n = 3) watt power settings. Total laser energy delivered varied between 6,000 and 13,800 joules. Erectile function was evaluated by pelvic nerve stimulation at 2, 4, and 8 weeks. Animals were then sacrificed to assess histopathology of the prostate at each time point.

Results: Histopathologic changes were noted in the prostate in a dose‐dependent manner and did not vary with different laser power settings. In dogs that received ˜10,000 J, substantial prostate ablation confined within the capsule was achieved in every prostate gland. Adequate erectile responses were noted in five of six animals; all received < 10,000 J. In one animal that received a total dose of 13,800 J, an erectile response was not obtained, and histology revealed both prostatic capsule perforation in close proximity to the cavernous nerves and thermal neural damage.

Conclusions: We conclude that cavernous nerve damage may result from excessive doses of laser energy during transurethral laser treatment of the prostate gland. In canines, the upper limit for periprostatic injury is between 10 and 14,000 joules. © 1995 Wiley‐Liss, Inc.
First vaginal delivery at an older age: Does it carry an extra risk for the development of stress urinary incontinence?
Authors: Groutz Asnat , Helpman Limor , Gold Ronen , Pauzner David , Lessing Joseph B. , Gordon David
Published: March 2007

Aims

First delivery at an older age is not an uncommon event in modern obstetric practice. The present study was undertaken to compare the prevalence of postpartum stress urinary incontinence (SUI) according to maternal age and mode of delivery.

Methods

Fifty two consecutive elderly primiparae (mean age 40.0 ± 1.8) who underwent spontaneous vaginal delivery, 42 consecutive elderly primiparae (mean age 40.7 ± 3.6) who underwent elective cesarean section, and 92 consecutive young primiparae (mean age 26.2 ± 2.5) who underwent spontaneous vaginal delivery were interviewed 1–2 years postpartum about the symptom of SUI. Women who had SUI before pregnancy were not enrolled. Obstetric data were collected from computerized hospital records.

Results

The prevalence of SUI 1–2 years after spontaneous vaginal delivery was significantly higher in elderly compared with younger primiparae (38.5% vs. 9.8%, respectively). Elderly primiparae who underwent elective cesarean section had a significantly lower prevalence of postpartum SUI than those delivered vaginally (16.7% vs. 38.5%, respectively). Further comparison of stress‐incontinent versus continent elderly primiparae failed to reveal significant demographic or obstetric differences, except for increased prevalence of SUI during pregnancy among incontinent patients (45% vs. 19%, respectively).

Conclusions

First vaginal delivery at an older age carries an increased risk for postpartum SUI. Stress‐incontinent women also had higher prevalence of SUI during pregnancy. This finding implies that the pathophysiologic process of SUI begins during pregnancy, prior to active labor and delivery. Nonetheless, elective cesarean section in these women has a protective effect and lowers the risk of developing postpartum SUI. Neurourol. Urodynam. 26:779–782, 2007. © 2007 Wiley‐Liss, Inc.
Alphafetoprotein, cholinesterases and rapidly adhering cells in the prenatal diagnosis of neural tube defects
Authors: Seller Mary J. , Cole Kathleen J. , Merritt Bernadette L.
Published: March 2007

Amniotic fluid cholinesterases tested on polyacrylamide gel and rapidly adhering cell analysis were compared in their efficiency at diagnosing fetal neural tube defects in three cases where the alphafetoprotein results were equivocal. While rapidly adhering cells were also equivocal, the cholinesterases consistently gave a clear indication of fetal abnormality.
Prenatal diagnosis of congenital enzymopenic methaemoglobinaemia with mental retardation due to generalized cytochrome b5 reductase deficiency: First report of two cases
Authors: Junien C. , Leroux A. , Lostanlen D. , Reghis A. , Boue J. , Nicolas H. , Boue A. , Kaplan J. C.
Published: March 2007

Prenatal diagnosis of congenital enzymopenic methaemoglobinaemia (CEM) with mental retardation was performed in two fetuses at risk for generalized NADH‐cytochrome b5 reductase deficiency. In the first case the enzyme activity of cultured amniotic cells was in the heterozygous to normal range. The mother delivered a normal baby with normal enzyme activity in cord blood cells. In the second case, the amniotic cells were almost completely enzyme deficient. The pregnancy was terminated, and the diagnosis of homozygous NADH‐cytochrome b5 reductase deficiency was confirmed in cord blood cells, in several different tissues and in cultured fibroblasts from the aborted fetus.
The effect of the introduction of prenatal diagnosis on the reproductive history of women at increased risk from neural tube defects
Authors: Laurence K. M. , Morris Jenny
Published: March 2007

The reproductive history of 45 couples at increased risk for neural tube defect (NTD) who came for genetic counselling in 1970 and 1971 were compared with a similar number counselled in 1975 and 1976, when prenatal diagnostic tests were freely offered. They were subsequently interviewed in their homes and had their reproductive history recorded to the end of 1973 and 1978 respectively. Nearly all had a previous child with an NTD and none of the women were pregnant at the time of counselling.

The effect of prenatal diagnosis was to speed somewhat the decision about further pregnancies, but the number of couples deciding on no further children and on having further pregnancies were almost identical in the two groups. The average number of pregnancies was 2·8 per family, with only 1·2 surviving children. The pregnancy outcomes are discussed as are the reasons for not attempting further pregnancies in both groups, which included very high risk of recurrence, a surviving spina bifida child, inability to accept the tests or its implications. Ninety per cent of the second group had tests. Their reactions to the tests were favourable but all complained of the waiting time between amniocentesis and obtaining the results. They all would have tests again in any future pregnancy. The reason for women not having prenatal diagnostic tests included inability to accept termination. It is concluded that couples in South Wales decide either to have no more children or to have further pregnancies regardless of tests. but tests speed a decision and enable the women to enjoy the pregnancy after obtaining the results, and that an NTD greatly reduces the number of children per family. A termination for an NTD is much more acceptable to most than an NTD at term. The reasons for this are discussed.
Detection and isolation of fetal cells from maternal blood using the flourescence‐activated cell sorter (FACS)
Authors: Iverson G. Michael , Bianchi Diana W. , Cann Howard M. , Herzenberg Leonard A.
Published: March 2007

The presence of fetal cells in the maternal circulation during pregnancy has been suggested by repeated observations of small numbers of cells containing Y chromatin or a Y chromosome in the blood of pregnant women. With the fluorescence‐activitated cell sorter (FACS), we have used antibodies to a paternal cell surface (HLA) antigen, not present in the mother, to select fetal cells from the lymphocyte fractions of a series of maternal blood samples, collected as early as 15 weeks of gestation. These sorted cells have been examined for a second paternal genetic marker, Y chromatin. Y chromatin‐containing cells were found among the sorted cells from prenatal maternal blood specimens in 8 pregnancies subsequently producing male infants whose lymphocytes reacted with the same antibodies to paternal antigen used for sorting with the FACS. In each of 17 pregnancies resulting in male infants who failed to inherit the antigen detected by the antibodies used for cell sorting, Y chromatin‐containing cells were not found prenatally. The use of two paternal genetic markers, a cell surface antigen and nuclear Y chromatin, to identify fetal cells in maternal blood permits us to conclude that these cells are present in the mother's circulation, as early as 15 weeks gestation. Further development of the techniques reported here could lead to widespread screening of maternal blood samples during pregnancy for detection of fetal genetic abnormalities.
Short communications prenatal detection of the autosomal recessive type of polycystic kidney disease by trehalase assay in amniotic fluid
Authors: Morin P. R. , Potier M. , Dallaire L. , Melançon S. B. , Boisvert J.
Published: March 2007

We report relatively high trehalase activity in amniotic fluid of a fetus affected with the autosomal recessive type of polycystic kidney disease (type II), suggesting that prenatal detection of this condition could be done on this basis in conjunction with ultrasonography.
Four years' experience of maternal alpha‐fetoprotein screening and its effect on the pattern of antenatal care
Authors: Ward R. H. T. , Fairweather D. V. I. , Whyley G. A. , Shirley I. M. , Lucas M.
Published: March 2007

Estimation of alpha‐fetoprotein (A.F.P.) in maternal serum was used as a screening method for the detection of fetal neural tube defect (N.T.D.) in 7315 women over a four year period. Of these, 5668 pregnancies were tested between 15 and 21 weeks. Action was advised in 129 patients (2·3 per cent). In 74 patients, the only action required was reviewing the notes, including the report of any ultrasound examination, and repeating the blood A.F.P. Detailed ultrasound including scanning the fetal spine was requested in 47 patients and amniocentesis was advised in 19 of these (0·33 per cent). In practice the incidence of amniocentesis was 0·28 per cent as three patients declined our advice. The programme gave detection rates between 15 and 21 weeks of 100 per cent and 75 per cent respectively for anencephaly and open spina bifida. A high fetal mortality was associated with persistently elevated blood A.F.P. levels whether amniocentesis was performed or not.
Maternal environment and the expression of murine neural tube defects
Authors: Seller Mary J. , Beck Susan E. , Adinolfi Matteo , Polani Paul E.
Published: March 2007

The role that genetic and environmental factors play in triggering neural tube defects in the mouse mutant curly‐tail (ct) were investigated by transplanting curly‐tail blastocysts into the uterus of either curly‐tail females or females of an unrelated A strain with a low natural incidence of abnormalities of the neural tube. The percentages of fetuses with neural tube defects were found to be similar in both groups.

These results show that in curly‐tail mice exencephaly and spina bifida are manifested independently of the maternal environment.
Trisomy 20 mosaicism in a foetus
Authors: McDermott A. , Gardner A. , Ray B.
Published: March 2007

A widespread distrust in the significance of the observation of trisomy 20 mosaicism in amniotic fluid cultures has led to an increasing belief that this particular type of aneuploidy is of extra foetal origin and is clinically incosequential. The report presents an example of amnoitic fluid cell mosaicism for trisomy 20 which was ultimately confirmed in the foetus, and proposes that, in spite of the absence of obvious congenital malformation from the foetus, trisomy 20 mosaicism in amnoitic fluid cultures should be regarded with the same deference as mosaicism for any other autosome of unknown effect.
Communication openness with friends, relatives and children of couples having amniocentesis
Authors: Ashery Rebecca Sager
Published: March 2007

In a study of couples having amniocentesis for prenatal diagnosis of genetic defects, it was found that couples were open in telling friends and relatives about the procedure. Couples were more conservative, however, in telling their children about amniocentesis and the implications of a positive diagnosis.
Technical and theoretical considerations in the HLA typing of amniotic fluid cells for prenatal diagnosis and paternity testing
Authors: Pollack M. S. , Heagney S. D. , Braun D. , O'neill G. J.
Published: March 2007

HLA typing of amniotic fluid cells has been used for the prenatal diagnosis of the HLA linked diseases congenital adrenal hyperplasia (21‐OH‐deficiency (21‐OH‐def) type) and complement C4 deficiency and it has also been used for the prenatal de termination of paternity. There are, however, technical difficulties in this test associated with the weak expression of some B locus antigens on amniotic fluid cells, and theoretical difficulties related to associations between particular HLA antigens and the 21‐OH‐def allele. Since certain HLA‐B locus antigens are found in significantly increased frequencies among patients with 21‐OH‐def, there is a relatively high incidence of HLA‐B homozygosity among the patients and over 40 percent of the parents of these patients share one or more HLA‐B locus antigens. Results of some prenatal HLA typing tests may thus be difficult to interpret, and supplementary tests should be used whenever possible. HLA typing of amniotic cells is, however, the only available procedure for prenatal diagnosis of C4 deficiency and it is the best available procedure for prenatal determination of paternity. A modification of our original procedure allows HLA typing to be performed with increased numbers of HLA typing sera, and sera with optimum reactivity for amniotic fluid cells have now been selected for the definition of most of the more commonly expressed HLA antigens. Although amniotic fluid cells do not express DR antigens, amniotic fluid cells can be typed for the HLA‐linked marker glyoxalase I (GLO) and this may be the informative for prenatal diagnosis in some cases.
Ultrasound demonstration of masses in a 15 week fetus: Hydrops in a fetus with umbilical cord occlusion
Authors: Shenker Lewis , Anderson William , Anderson Caroline
Published: March 2007

A fetal abnormality detected at 15 weeks by ultrasound consisted of cystic appearing masses in the neck and back region. The differential diagnosis included gonadal dysgenesis (Turner's syndrome) with cystic hygroma, neural tube defect, e.g. encephalocele or meningomyelocele, and fetal hydrops.

Intrauterine fetal demise occurred at 17 weeks. The fetus had marked edema possibly related to umbilical cord occlusion.
Ultrasonic detection of an abnormal mass in a fetus later shown to have trisomy 18
Authors: Heller Richard H. , Adams John E. , Hirschfeld Robert L. , Tapper Alan J.
Published: March 2007

Ultrasonic examination in a thirty‐eight year old woman about to undergo midtrimester amniocentesis suggested an intra‐abdominal fetal mass confirmed by amniography. The mass was a grossly distended urinary bladder. The patient aborted spontaneously before chromosome analysis demonstrated a 47,XY, + 18 karyotype.
Neural tube defects in trisomy 18
Authors: Nisani Rachel , Chemke Juan , Cohen‐Ankori Hana , Nissim Florens
Published: March 2007

Central nervous system anomalies in trisomy 18 are usually confined to structural abnormalities of brain development. Despite the recognized association of neural tube defects and trisomy 18, primary (true) anencephaly is uncommon in the classical trisomy 18 phenotype. A case of anencephaly with trisomy 18, diagnosed prenatally, is presented with a review of the literature of this association.
Glial and neuronal cells in amniotic fluid of anencephalic pregnancies
Authors: Von Koskull H. , Virtanen I. , Lehto V.‐P. , Vartio T. , Dahl D. , Aula P.
Published: March 2007

Cultured amniotic fluid cells from four anencephalic pregnancies were characterized in indirect immunofluorescence (IIF) microscopy using specific antibodies against different types of cytoskeletal intermediate filaments. Most of the cells showed a fine fibrillar cytoplasmic fluorescence with antibodies against glial fibrillary acidic protein (GFA), indicating that amniotic fluid cells in anencephalic pregnancies are of glial origin. The GFA‐positive cells were rapidly adhering and proliferating. They remained as the major cell type also in long term cultures, and could easily be recovered from liquid nitrogen without losing their GFA positivity. GFA‐positive cells were pleomorphic in appearance, and occurred in several morphologically different shapes. Amniotic fluid from one of the anencephalic cases contained typical neuronal cells, which in IIF were GFA‐negative but could specifically be stained with anti‐neurofilament antibodies. Most of the GFA‐negative cells in all the cases were fibroblasts, identified by their fluorescence only with antibodies against vimentin. Epithelial cells showing positive keratin‐fluorescence in IIF, were seen only occasionally.
Microculture of fetal blood for prenatal cytogenetic studies from blood‐stained amniotic fluid
Authors: Bricarelli F. Dagna , Arslanian A. , Carbone L. Doria Lamba , Chisci R. , Gessaga M. , Zucchinetti P.
Published: March 2007

An alternative method to the culture of amniotic fluid cells for prenatal diagnosis of chromosome disorders is proposed. Microculture of fetal blood can be used when fetal blood is drawn at amniocentesis through accidental puncture of the placenta. An easy discrimination of fetal red cells, a good response of fetal lymphocytes to PHA and the possibility of identification of the fetal karyotype from the maternal one are the technical bases of this method.

This technique offers some undoubted advantages: a reduced need for repeating amniocentesis because of a lack of growth of AF cells due to massive contamination with red cells; a result may be obtained sooner.

Thirty‐seven cases out of 1092 amniocenteses were processed in this way (3·4 per cent). In two cases no mitoses were obtained but in the others the diagnosis was confirmed by the results of AF cell culture and/or by the outcome of pregnancy.