bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of low‐intensity argon laser irradiation on mitochondrial respiration
Authors: Morimoto Yuji , Aral Tsunenori , Kikuchi Makoto , Nakajima Shinji , Nakamura Haruo
Published: March 2007

We studied influences of low‐intensity argon laser irradiation at various wavelengths on mitochondrial respiration in vitro. Isolated guinea pig liver mitochondria were suspended in an isotonic buffer solution (pH 7.4,37°C). The mitochondrial suspension was introduced into a constant temperature reaction chamber in which an irradiation fiber, a thermocouple, an oxygen electrode, and a stirrer were installed. Under respiratory conditions of state 4, state 3, and uncoupled respiration, mitochondrial oxygen consumption was measured during low‐intensity argon laser irradiations at 351nm, 458 nm, and 514.5 nm. The 351 nm and the 458 nm irradiations at 200 mW inhibited uncoupled respiration by 19% and 11%, respectively, and the irradiation at 351 nm inhibited state 3 respiration as well by 10%. In contrast, the 514.5 nm irradiation enhanced both state 3 and uncoupled respiration by 6–7%. Temperature reference experiments indicated that the thermal effect alone could not account for the effects of laser irradiation on mitochondrial oxygen consumption. These results suggest that the 351 nm and the 458 nm laser irradiation may injure the mitochondrial inner membrane, while the 514.5 nm laser irradiation may slightly promote the rate of ATP synthesis. © 1994 Wiley‐Liss, Inc.
Effect of the dynamic optical properties of water on midinfrared laser ablation
Authors: Walsh Joseph T. , Cummings Joseph P.
Published: March 2007

Water is a primary tissue chromophore in the midinfrared. Absorption of midinfrared radiation by water is a function of temperature and pressure, both of which rise rapidly during an ablative laser pulse. Data show that the absorption coefficient of water changes, by as much as two orders of magnitude, during a high‐irradiance laser pulse. We present an ablation model that is fundamentally based upon Beer's Law but considers changes in the absorption coefficient. The model predicts that Er:YAG laser cuts will be deeper than Er:YSGG laser cuts; an opposite prediction would be made based upon the static, low‐intensity absorption coefficient of water. The results of in vitro ablation of skin confirm that the dynamic optical properties of tissue need to be considered in the understanding of laser ablation as well as the design, manufacture, use, and regulation of clinical laser systems. © 1994 Wiley‐Liss, Inc.
Ex vivo optical properties of human colon tissue
Authors: Marchesini Renato , Pignoli Emanuele , Tomatis Stefano , Fumagalli Sabrina , Sichirollo Adele E. , Palma Silvana Di , Fante Marko Dal , Spinelli Pasquale , Croce Anna C. , Bottiroli Giovanni
Published: March 2007

Using a spectrophotometer equipped with an internal integrating sphere, the absorption (μa) and the reduced scattering (μs′) coefficients of ex vivo human colon tissues were evaluated from reflectance and transmittance measurements. μa and μs′ varied from 47.7 to 1.0 cm−1 and from 14.2 to 6.2 cm−1, respectively, on passing from 300 nm to 800 nm. These results can be used to estimate the optical penetration depths when photodynamic therapy or light‐induced fluorescence procedures are used.
Erb:YAG and Hol:YAG Laser Osteotomy: The Effect of Laser Ablation on Bone Healing
Authors: Buchelt Martin , Kutschera Hans‐Paul , Katterschafka Thomas , Kiss Harald , Lang Susanne , Beer Rudolf , Losert Udo
Published: March 2007

Sixty‐nine male Sprague Dawley rats were divided into three groups of 23 animals each and osteotomies were performed in group 1 with a power saw, in group 2 with the Erb:Yag laser, and in group 3 with the Hol:YAG laser. Two animals of each group were sacrificed 1 week, 4, 8, and 12 weeks after operation for histologic investigation, and five animals of each group at 4, 8, and 12 weeks after osteotomy for torque testing. Anterior‐posterior (AP) radiographs were taken at the same time points and investigated for callus formation and development of pseudoarthrosis. All tibiae osteotomied with the Ho1:YAG laser (group 3) developed pseudoarthrosis within 12 weeks and, therefore, torque testing could not be performed for this group. Biomechanical measurements of bone treated by power saw or Erb:YAG laser osteotomies, respectively, showed no significant statistical difference in the stability of bone between the two groups. Histologic examination after 1 week exhibited fibrous tissue at the site of osteotomy in rats of all three groups and additionally carbonization in rats of group 3. Saw osteotomies resulted in more callus formation than Erb:YAG osteotomies, but both techniques provoked a certain reunion within 8 weeks. Hol:YAG laser‐treated osteotomies, however, exhibited formation of dense fibrous tissue, carbonization and no callus formation within 12 weeks. Radiographic pictures showed more callus formation for saw osteotomies as compared to those performed with the Erb: YAG laser. For Hol:YAG laser osteotomies pseudoarthrosis was identified also radiologically. © 1994 WiIey‐Liss, Inc.
Laser patch welding: Experimental study for application to endoscopic closure of bronchopleural fistula, a preliminary report
Authors: Sensaki Koji , Arai Tsunenori , Tanaka Susumu
Published: March 2007

Background and Objective: Postoperative bronchopleural fistula is a serious complication following pulmonary resection. To close the bronchopleural fistula, we developed a new method of endoscopic patch welding using laser tissue welding between bronchial tissue and a patch.

Study Design/Materials and Methods: The feasibility of the laser patch welding was examined by in vitro and in vivo animal experiments. A newly developed carbon monoxide (CO) laser and an Argon ion laser were evaluated. Various tissue membranes and artificial membranes were evaluated as patch materials.

Results: We found that the combination of expanded polytetrafluoroethylene (e‐PTFE; 200 μm in thickness) and the CO laser with contact irradiation method offered the strongest laser patch welding. Using this combination, the irradiation at 400 W/cm2 for 10 seconds resulted in 16–18 g of measured traction strength at the welding spot (2 mm in diameter). The welded e‐PTFE patch at bronchial stump remained for 5 weeks.

Conclusion: Our results encourage use of this novel laser patch technique for clinical applications. © 1995 Wiley‐Liss, Inc.
Is there a need for guidelines for OB/GYN residents to use the laser?
Authors: Olivar August C. , Simon Helene
Published: March 2007

Background and Objective: With the developing technologies and the extensive use of different wavelength lasers for treatment of some gynecologic conditions, many residencies in the United States face pressure to give credentialing to residents wishing to utilize the laser(s). The objective of this study was to assess the need for credentialing.

Study Design/Materials and Methods: A survey was sent to all U.S. program directors of obstetrics and gynecology.

Results: Of 281 surveys mailed, 138 responded (49.1%); 136 utilized some wavelength laser in the treatment of some gynecologic conditions. The most commonly used laser was the carbon dioxide (CO2), and the least used was the argon laser. Eighty‐four programs (61.8%) had a written policy; 54 (38.2%) did not. Postgraduate courses were necessary in 81 programs (59.6%), leading to some form of credentialing.

Conclusions: The vast majority of programs (98.6%) utilized some wavelength laser as a therapeutic modality in gynecology, and 73.5% of the residency programs would like standardized guidelines for residents. © 1995 Wiley‐Liss, Inc.
Lasers in dentistry
Authors: Wigdor Harvey A. , Walsh Joseph T. , Featherstone John D. B. , Visuri Steven R. , Fried Daniel , Waldvogel Joseph L.
Published: March 2007

Since the development of the ruby laser by Maiman in 1960, there has been great interest among dental practitioners, scientists, and patients to use this tool to make dental treatment more pleasant. Oral soft tissue uses are becoming more common in dental offices. The possible multiple uses of lasers in dentistry, beyond soft tissue surgery and dental composite curing, unfortunately, have not yet been realized clinically. These include replacement of the dental drill with a laser, laser dental decay prevention, and laser decay detection. The essential question is whether a laser can provide equal or improved treatment over conventional care. Safe use of lasers also must be the underlying goal of proposed or future laser therapy. With the availability and future development of different laser wavelengths and methods of pulsing, much interest is developing in this growing field. This article reviews the role of lasers in dentistry since the early 1960s, summarizes some research reports from the last few years, and proposes what the authors feel the future may hold for lasers in dentistry. © 1995 Wiley‐Liss, Inc.
High power Ho:YAG laser ablation of intervertebral discs: Effects on ablation rates and temperature profile
Authors: Buchelt Martin , Schlangmann Bodo , Schmolke Stephan , Siebert Werner
Published: March 2007

Background and Objective: As the Ho:YAG laser gained increasing importance in recent experimental and clinical investigations, this study was performed to investigate the effect of power on ablation rates and temperature during disc ablation with a high power Ho:Yag laser under simulated clinical conditions.

Study Design/Materials and Methods: A high power Ho:YAG laser was used to investigate the influence of increasing power from 10 to 32 Watt on ablation rate (mg) and temperature (°C). Ablation weight was measured by a precision scale calculating the difference of the pre‐ and postlasing weight of the specimen after application of total energies of 1,000, 1,500, and 2,000 J. Temperatures were measured by thermoprobes, which were connected via a thermomodule to an amplifier and the signal was plotted by a computer with appropriate software.

Results: Whereas ablation rate rose almost linearly with total energy, increasing power above 20 W did not essentially improve ablation rate. Temperatures reached their highest values after application of a total energy of 500 J and did not rise further, whereas increasing power did not induce a rise in temperature.

Conclusions: Regarding the chosen experimental setting, maximum temperatures are reached after application of 500 J, and increasing power does not induce a rise in temperature. © 1995 Wiley‐Liss, Inc.
HeNe laser therapy by fibroendoscopy in the mucosa of the equine upper airway
Authors: Gomez‐Villamandos R. J. , Valenzuela J. M. Santisteban , Calatrava I. Ruiz , Gomez‐Villamandos J. C. , Jurado I. Avila
Published: March 2007

Background and Objective: A study was made of the effects of low‐level laser irradiation on the cicatrization of superficial wounds in the pharyngeal mucosa of the horse.

Study Design/Materials and Methods: Duplicate pharyngeal mucosal ulcers were induced in 12 Spanish horses with submucosal injection of sulfuric acid. A fibroendoscope and an He‐Ne laser were used to treat one of the ulcers and the second ulcer in each animal was left untreated, serving as a control. Biopsy samples for the histological study were taken after the seventh laser therapy session from the two animals.

Results: Irradiated lesions cicatrized at 10.5 days and nonirradiated lesions cicatrized at 18.0 days. Statistical analysis revealed highly significant differences (P < 0.0001) between the irradiated and control groups. Histological study of the control samples showed epithelial coagulation necrosis, edema, and microthrombi. However, in samples from the irradiated lesions no inflamatory edema, numerous active fibroblasts, connective tissue, and intensive epithelial regeneration were observed.

Conclusion: Macroscopic and microscopic results indicated that laser treatment accelerated the cicatrization. Irradiated lesions cicatrized faster than control. These results suggest beneficial effects of low‐level laser irradiation therapy on equine pharyngeal ulcerative lesions. © 1995 Wiley‐Liss, Inc.
Applications of lasers in gastroenterology
Authors: Nishioka Norman S.
Published: March 2007

In this article the clinical uses of lasers in gastroenterology are reviewed. The endoscopic delivery of light for therapeutic as well as diagnostic purposes is discussed. Current research directions in the field are also indicated where appropriate. © 1995 Wiley‐Liss, Inc.
Laser‐induced release of liposome‐encapsulated dye to monitor tissue temperature: A preliminary in vivo study
Authors: Mordon S. , Desmettre T. , Devoisselle J. M.
Published: March 2007

Background and Objective: The objective of this in vivo study was to assess the possible use of temperature‐sensitive liposomes as a new approach to monitor the temperature induced by a laser.

Study Design: An in vivo/ex vivo study was performed in rat liver after i.v. injection of liposomes loaded with a fluorescent dye.

Materials and Methods: Temperature‐sensitive liposomes (DSPC: Di‐Stearoyl‐Phosphatidyl‐Choline) were loaded with carboxyfluorescein. These liposomes (1 ml solution) were injected into adult male Wistar rats. Two hours later, the liver was exposed and irradiated with a 100 W Nd:YAG laser using pulses lasting from 100 to 260 ms. Simultaneously, the surface temperature was recorded with a thermographic camera. The fluorescence emission was measured with a fluorescent imaging system.

Results: The results showed that the dye was released in response to laser energy. The amount of the drug release increased linearly with increasing temperature in the range 42–60°C. Moreover, the release occurred in a short period of time upon brief exposure to its phase transition temperature.

Conclusion: The feasibility of temperature monitoring by using laser‐induced release of liposome‐encapsulated dye was demonstrated. This procedure could conceivably prove useful for controlling the thermal coagulation of biological tissues such as blood vessels. © 1995 Wiley‐Liss, Inc.
Model study to investigate the contribution of spallation to pulsed laser ablation of tissue
Authors: Paltauf Günther , Schmidt‐Kloiber Heinz
Published: March 2007

Background and Objective: Absorption of a short laser pulse produces high thermoelastic stress in the irradiated volume. The relaxation of this stress at a free (tissue–air) surface leads to tensile loading, resulting in mechanical spallation. Using model substances, we investigated the role of this effect in tissue ablation.

Study Design/Materials and Methods: Stained water and gelatine were irradiated with short pulses (8 ns duration) from a Nd:YAG laser at 1,064 nm wavelength. The dynamics of the induced effects were observed with laser‐flash photography and stress wave detection.

Results: Spallation is indicated by the formation of cavitation bubbles below the irradiated surface and is strongly influenced by impurities serving as nucleation sites. Material ejection due to spallation was observed in the liquid sample at a fluence leading to a temperature below the boiling point but needed a temperature in excess of 100°C in gelatine, owing to the small mechanical energy available for this process, estimated to be <1%.

Conclusion: The mechanical action of thermoelastic stress waves is characterized by high stress amplitudes but low energetic efficiency. A model combining spallation and vaporization is therefore proposed for efficient tissue ablation.
Clinical and preclinical photodynamic therapy
Authors: Fisher Anita M. R. , Murphree A. Linn , Gomer Charles J.
Published: March 2007

Photodynamic therapy (PDT) is a treatment modality that utilizes a photosensitizing drug activated by laser generated light, and is proving effective for oncologic and nononcologic applications. This report provides an overview of photosensitizers, photochemistry, photobiology, and the lasers involved in photodynamic therapy. Clinical and preclinical PDT studies involving Photofrin and various second generation photosensitizers are reviewed. © 1995 Wiley‐Liss, Inc.
Laser photocoagulation of prostate: Influence of dosimetry
Authors: Motamedi Massoud , Torres Jorge H. , Orihuela Eduardo , Pow‐Sang Mariela , Cowan Daniel F. , Warren Michael M.
Published: March 2007

Background and Objective: Recently, increasing enthusiasm has been shown for application of lasers for the treatment of benign prostate hyperplasia (BPH). However, little is known about the thermodynamics of prostatic tissue response during laser irradiation and how the treatment outcome can be optimized. Our objective was to conduct a systematic study of the influence of exposure parameters on the extent of tissue coagulation and to determine the effects of rate of tissue heating on lesion size by comparing the tissue response to high laser power rapid heating vs. low laser power slow heating.

Study Design/Materials and Methods: Nd: YAG laser irradiation of prostate was performed in 15 mongrel canines, using an incident power of 15, 30, or 50 Watts (at the fiber tip) and an exposure time varying from 30 to 300 seconds. The laser beam was delivered via a Urolase side‐emitting catheter. The tissue response was compared based on gross as well as histological evaluations of thermal lesions.

Results: The depth of coagulation necrosis increased as the laser power was reduced from 50 W to 30 W and further to 15 W while the total delivered energy was kept constant at 2,700 J by adjusting the exposure time. The difference between the three heating rates was more dramatic when the estimated volume of coagulated tissue was considered. Increasing the irradiation tune for the low power (15 W) from 180 to 300 seconds resulted in enlarging the coagulated volume by a factor of 1.6. However, for high power (50 W), increasing the exposure time from 54 to 90 seconds resulted in increasing the coagulated volume by a factor of 1.2. Conclusion: This study suggests that a slow heating regimen yields larger volumes of coagulation necrosis than the currently used rapid heating approach. © 1995 Wiley‐Liss, Inc.
Creation of a volume lesion in the dog prostate using neodymium: YAG laser coagulation: Concepts for clinical treatment
Authors: Perlmutter Aaron P. , Lopez Miguel , Vaughan E. Darracott
Published: March 2007

Background and Objective: The purpose of this study was to determine the geometrical development of a coagulated zone in the canine prostate during free beam side fire Nd: YAG laser coagulation.

Study Design/Materials and Methods: A series of 10 male dogs underwent endoscopic prostatic Nd: YAG fixed position laser coagulation through a suprapubic cystotomy using a right‐angle deflecting delivery catheter (Microvasive, Boston, MA) at times varying from 10 to 120 seconds at 30 watts. In addition, two dogs underwent lasing by pulling the catheter at 1 mm/s in four quadrants. Acute gross and microscopic pathology specimens were prepared and the lesion shape and volume determined.

Results: Analysis of the coagulated volume showed that during the initial 15 seconds of lasing, the zone of coagulation approximates a sphere centered on the urothelium opposite the laser fiber. However, as lasing progressed, the lesion changed from a sphere to an expanding ellipse. This changing geometry can be explained by the absorption and scatter characteristics of the laser and the temperature equilibrium that is established within the prostate.

Conclusion: An understanding of this time‐dependent geometrical shift from a sphere to an ellipse allows the surgeon to supplement the fixed protocols for lasing at certain positions for given amounts of time. Specific plans can then be established for tissue at the bladder neck, apex, anterior stroma, floor, and irregular prostatic regrowth. © 1995 Wiley‐Liss, Inc.
Double‐blind, placebo‐controlled investigation of the effect of combined phototherapy/low intensity laser therapy upon experimental ischaemic pain in humans
Authors: Mokhtar Basim , Baxter G. David , Walsh Deirdre M. , Bell A. Jean , Allen James M.
Published: March 2007

Background and Objective: This study assessed the putative analgesic effect of combined monochromatic light/laser irradiation at low intensity (660–950 nm; 31.9 J/cm2; pulsed at 16 or 73 Hz). Study Design/Materials and Methods: The investigation was completed under double‐blind conditions using a standardised form of the submaximal effort tourniquet technique. Healthy male volunteers naive to the experimental conditions (n = 45) attended on two occasions for the purposes of pain induction, the first during which baseline data were obtained and on a second occasion during which they were randomly allocated to one of two treatments or a placebo condition. For the treatment conditions, irradiation was applied to the ipsilateral Erb's point at the parameters stated; for the placebo condition, sham “irradiation” was delivered using a dummy unit. Pain was measured using computerised visual analogue scales and McGill Pain Questionnaires (MPQ) to assess “current pain intensity” and “worst pain experienced,” respectively.

Results: Analysis of variance and appropriate post hoc tests demonstrated only a weak (but significant) hypoalgesic effect compared to placebo (P<0.05) in the treatment group irradiated at 16Hz for the sensory component of the MPQ; other comparisons were found to be nonsignificant.

Conclusions: These results do not provide convincing evidence for the hypoalgesic potential of combined monochromatic light/laser irradiation, at least at the parameters used here, and thus indicate the necessity of additional work to investigate this modality further in order to assess the potential benefit, if any, of such treatment in the clinical setting. © 1995 Wiley‐Liss, Inc.
Laser‐assisted removal of a foreign body in the bronchial system of an infant
Authors: Boelcskei Pal L. , Wagner Manfred , Lessnau Klaus‐Dieter K. L.
Published: March 2007

Background and Objective: Foreign body aspiration is an important cause of acute respiratory distress in children. Removal by use of rigid tracheo‐bronchoscopy under general anesthesia is usually the treatment of choice, but this technique is sometimes unsuccessful. Thoracotomy in these instances often cannot be avoided.

Study Design/Patients and Methods: Case report with review of the literature. The patient was 19 months old with an aspirated foreign body. A Neodym:YAG laser with a special small‐size delivery system was inserted into the rigid “baby” bronchoscope. The NeodymiumrYAG laser with a wavelength of 1,064 nm and a Helium‐Neon 630 nm light guide provided an aiming beam to weaken and cut the aspirated chicken bone.

Results: The foreign body could be easily removed with a regular biopsy forceps.

Conclusion: We discuss a patient in whom laser‐assisted rigid tracheobronchoscopy obviated the need for thoracotomy. © 1995 Wiley‐Liss, Inc.
Sodium flux and bioenergetics in the ischemic rat liver
Authors: Blum Haywood , Osbakken Mary D. , Johnson Robert G.
Published: March 2007

Concurrent 23Na and 31P nuclear magnetic resonance spectroscopy has been employed to study the effects of ischemia upon the high‐energy phosphagens and sodium ion concentration within the in vivo rat liver. High‐energy phosphates in the form of ATP were depleted within 10 min of the onset of ischemia when measured by NMR. However, similar liver samples subjected to analytical biochemistry retained 27 ± 12% of their ATP after a similar 10‐min ischemic insult. Time‐dependent 23Na NMR measurements, obtained in the presence of the shift reagent Dy(TTHA) to distinguish intracellular from extracellular sodium, revealed a rapid rise in the intracellular sodium when the liver was made ischemic. Intracellular and extracellular sodium concentrations approached equilibrium with an exponential time constant of 14.7 ± 7 min. The initial rate of sodium influx was calculated to be 1.50 meq · 1−1 · min−1. The results indicate that the ischemic liver has a high passive sodium permeability and that NMR detectable 31P signals reflect the actual availability of cytosolic high‐energy phosphates to enzymes, in this instance the membrane‐bound [Na+, K +]‐ATPase. © 1991 Academic Press. Inc.
Continuous overnight monitoring of bladder activity in vesicoureteral reflux patients: II. Bladder activity types
Authors: Nielsen J. Bugge , Nøsbrgaard J. P. , Schwartz SøSrensen S. , Munch JøSbrgensen T. , Djurhuus J. C.
Published: March 2007

Continuous overnight monitoring of the bladder activity was undertaken in children with vesicoureteral reflux. The investigation succeeded in 46 of 56 patients and showed bladder activity in all cases. Three types of bladder activity were revealed. One consisting of single contraction episodes exhibited periodicity with intervals of approximately 90 min. The second type consisted of a complex of contractions with increasing amplitude. They frequently lead to voiding. This type of activity seemed to be related to the bladder fullness. The third type of bladder activity consisted of vigorous repetitive contractions, most frequently found in the nonenuretic part of the material. The contractions in type III most frequently occurred with a frequency of 3–6/min.

The degree of reflux was related to the type of bladder activity. Thus, the degree of reflex was significantly increased in patients with the second and third type of bladder activity when compared to patients with type I. The study shows that bladder activity takes place outside provocational episodes, e.g., cystometry and micturition, and seems to be closely related to the severity of reflux.
Bladder diary patterns in detrusor overactivity and urodynamic stress incontinence
Authors: Parsons Matthew , Amundsen Cindy L. , Cardozo Linda , Vella Maria , Webster George D. , Coats Alfred C.
Published: March 2007

Aims

Our aims were: (1) to describe and compare frequency‐volume and incontinence episode patterns in patients with urodynamic stress incontinence (USI) and detrusor overactivity (DO) as measured by a hand‐written and computer‐analyzed bladder diary and (2) to compare degree of separation between these clinical groups produced by raw diary measurements and after age‐ and total‐volume‐adjustment against a reference population.

Materials and Methods

We studied 58 patients with USI, 29 with DO, and 22 with both USI and DO. From 3‐day hand‐written and computer‐analyzed bladder diaries, we calculated average and maximum volume voided (Vol/Void), voiding frequency and volume voided over 24 hr, and number, size and type (whether accompanied by activity or urge) of incontinence episodes.

Results

Compared to the USI patients, the DO patients tended to have (1) higher voiding frequency, (2) lower Vol/Void, (3) more urge‐related, than activity‐related leaks, (4) smaller volume, and equally frequent leaks and (5) more severe incontinence symptoms. The age‐ and volume‐adjusted percentiles better separated the USI and DO groups' frequency and volume measurements than did the raw measurements. Unexpectedly high percentages of our USI patients had low Vol/Void measurements, high voiding frequency, and predominantly urge‐related leaks. A subgroup of 29 USI patients with “low” (average volume <30th reference population percentile) Vol/Void measurements had high incidences of urgency and urge‐related leaks.

Conclusions

Reference population percentiles better separate the frequency/volume patterns of USI and DO than do the raw measurements. We found a subgroup of USI patients that had an OAB‐like clinical picture. Neurourol. Urodynam. 26:800–806, 2007. © 2007 Wiley‐Liss, Inc.
The use of amniotic fluid AFP action limits in diagnosing open neural tube defects
Authors: Brock David J. H.
Published: March 2007

An analysis is made of alphafetoprotein (AFP) concentrations in 3630 amniotic fluids submitted for prospective prenatal diagnoses over a 7‐year period. There were 89 cases of anencephaly, 74 of open spina bifida and 3467 with normal singleton outcomes. The AFP data were expressed in both standard deviations above the mean and multiples of the normal median for individual weeks of gestation. False positive and false negative rates were comparable in the two systems at selected cut‐offs. It is concluded that either system may be used in setting action limits for the primary distinction of unaffected pregnancies from those in which an open neural tube defect is present.
Prenatal diagnosis of congenital adrenal hyperplasia (21‐OH deficiency type) by HLA typing
Authors: Couillin P. , Boue J. , Nicolas H. , Cheruy C. , Boue A.
Published: March 2007

The close genetic linkage between HLA‐B and congenital adrenal hyperplasia due to 21‐hydroxylase deficiency permits prenatal diagnosis of an affected fetus by HLA typing of amniotic fluid cells in pregnancies at risk.

Some families at risk, especially those with an affected girl with ambiguous genitalia, will only plan another pregnancy if a prenatal diagnosis is possible. After HLA typing of the index case, parents and eventually grandparents, the family were informed of the possibility of a prenatal diagnosis. Fibroblast cell lines were initiated from skin biopsies of the index cases and parents and were used as controls in the tests. HLA typing of the fetus was done on amniotic fluid cells grown in vitro using first, a microcytotoxicity test and second quantitative microabsorption test.

Ten prenatal diagnoses are reported. In two cases the HLA genotype indicated an affected fetus, examination of the aborted fetuses was in agreement with the diagnosis. In one case an affected male fetus was diagnosed, the pregnancy is in progress. In seven cases an unaffected infant was predicted (four carriers and three homozygous normal infants).
Can oculocutaneous albinism be diagnosed prenatally?
Authors: Haynes M. E. , Robertson E.
Published: March 2007

A study of scalp and forearm skin biopsies from normally pigmented fetuses of gestational ages 16 to 28 weeks has indicated that prenatal diagnosis of albinism is a theoretical possibility. Pigment is not present in cells of the epidermis but can be found in hair follicles at the bulbous peg stage in the scalp only. Such hair follicles are present in the scalp as early as 16 weeks gestation. The findings indicate that prenatal diagnosis of albinism could be made on a scalp biopsy within the second trimester of pregnancy.
Short communications In Utero diagnosis of Kleeblattschädel (cloverleaf skull)
Authors: Salvo Anthony F.
Published: March 2007

Kleeblattschädel anomaly, or cloverleaf skull (Comings, 1965) is a name given to a grotesque appearance of the skull resulting from congenital premature synostosis of the various sutures. These will usually include the coronal and lambdoidal sutures. This rare entity is usually diagnosed during the newborn period and is verified by radiological findings. With the advent of ultrasound. and its frequent usage in obtaining bi‐parietal diameters, prenatal diagnosis of this skull abnormality is possible, and has recently been reported (Brahman et al. 1979). This communication reports another case of prenatal diagnosis of Kleeblattschädel by ultrasound.
Catecholamine metabolites in amniotic fluid from fetuses with neural tube defects
Authors: Lagercrantz H. , Sjöquist B.
Published: March 2007

Catecholamine metabolites were analysed in amniotic fluid from fetuses with neural tube defects and controls. HMPG (4‐hydroxy‐3‐methoxyphenyl‐glycol) assumed to originate mainly from the central nervous system and VMA (4‐hydroxy‐3‐methoxymandelic acid) formed in the peripheral nervous system were determined by gas chromatography‐mass spectrometry. The HMPG/VMA ratio was increased (more than 2 SD) compared with controls in ten out of fifteen cases of neural tube defects.
Prenatal diagnosis of congenital adrenal hyperplasia (CAH) due to 21‐hydroxylase deficiency by steroid analysis in the amniotic fluid of mid‐pregnancy: Comparison with HLA typing in 17 pregnancies at risk for CAH
Authors: Forest Maguelone G. , Bétuel Hervé , Couillin Philippe , Boué André , David Michel , Floret Daniel , Francois René , Guibaud Pierre , Plauchu Henri , Rappaport Raphaël
Published: March 2007

Amniotic fluid (AF) levels of 17‐hydroxyprogesterone (17OHP) and testosterone (T) were determined at 16–17 weeks in 17 pregnancies at risk for CAH and results compared to 75 normal controls. The fetus was predicted to be unaffected in 12 cases on the findings of normal AF levels of both 17OHP and T and the latter allowed a correct prediction of fetal sex in all instances. HLA typing confirmed normality in 12 cases revealing 5 carriers, 5 homozygous normal and 2 indeterminate. Steroid levels of the 2 groups were similar.

Three fetuses were predicted to be CAH affected on unambiguously high levels of 17OHP and T (in female only). HLA typing was in agreement, and the diagnosis was confirmed in 2 abortuses and a female newborn by physical and hormonal studies.

In the last 2 cases AF levels of OHP and T were normal but HLA (A/B/C) genotypes were identical to the CAH affected siblings. Normal physical and hormonal findings in the 2 aborted fetuses would exclude the possibility of an in utero virilizing form of CAH. The discrepancy could be explained on the basis that the fetuses had an allelic form of 21‐hydroxylase deficiency or on the basis of recombination (not fully tested).

It is concluded that a fully informative prenatal diagnosis of CAH should not rely entirely on HLA typing but on hormonal studies.
The possibility of prenatal diagnosis by gene dosage: Confirmation of duplication 10q24→qter from Got‐l activity in fetal erythrocytes
Authors: Dallapiccola B. , Pachì A. , Ferranti G. , Micara G. , Magnani M. , Dachà M.
Published: March 2007

The activity of four enzymes, including GOT‐1, has been investigated in the erythrocytes of a 10q→24qter trisomic fetus. Analyses have been performed on a feto‐maternal blood mixture sampled by fetoscopy and on red cells obtained by cardiac puncture, following therapeutic abortion.

The demonstration of a 40 percent increase of GOT‐1 activity, as compared to normal fetuses of similar gestational age, suggests that gene dosage studies may be a useful confirmatory technique in prenatal diagnosis of unbalanced chromosomal aberrations.

Practical application of a similar diagnostic approach is conditioned by (1) precise characterization of fetal chromosome imbalance; (2) confirmed assignment of the gene locus coding for the gene product under investigation; (3) evidence of a linear proportionality between gene dose and concentration of the gene product in patients with the same chromosome imbalance detected in the fetus; (4) knowledge of the range of normal variation at different weeks of gestation of the enzyme activity to be tested in the fetus; (5) safety of fetal sampling procedure.
Prenatal diagnosis for the detection of down syndrome: Why are so few eligible women tested?
Authors: Lippman‐Hand Abby , Piper Martha
Published: March 2007

Postpartum women ≧ 33 years were interviewed about their attitudes to and knowledge and use of prenatal diagnosis. Overall, 68 per cent had heard of prenatal diagnosis; nevertheless, only 30 per cent of those ≧ 35 had actually been tested. The only significant difference between eligible women who were tested and those who were not was maternal age. Of those tested, half requested it for themselves; conversely, only two‐thirds of women requesting the procedure actually received it. Among women not tested, 82 per cent were never offered the procedure by the physician. Expressed attitudes to prenatal diagnosis were strongly positive among all women, with 75 per cent continuing to want testing after learning both their age‐specific risk of having an affected child and the possible risks of amniocentesis. The data document a potential demand for amniocentesis far in excess of current use and present service facilities. They suggest, moreover, that underuse may reflect professional hesitation and underreferral more than consumer lack of demand or reluctance to be tested.
45,X karyotype: May the diagnosis be suspected on ultrasonic examination in the second trimester of pregnancy?
Authors: Tabor Ann , Bang Jens , Philip John
Published: March 2007

We report three cases of Turner's syndrome with cystic hygromata, which were diagnosed by routine ultrasound scanning before amniocentesis in the second trimester of pregnancy. Maternal and amniotic level of alpha‐fetoprotein were normal. Karyotyping carried out afterwards showed a 45,X karyotype.

Our data indicate, that cystic hygromata in Turner's syndrome may coexist with a normal amniotic fluid AFP, thus questioning the theory of leakage from the hygroma.

It remains to be investigated if all cases of Turner's syndrome present a cystic hygroma in utero.
Comparison of fetal and maternal chromosome polymorphisms: Applications in prenatal diagnosis
Authors: Frydman M. , Greenberg D. A. , Mohandas T. K. , Kaback M. M.
Published: March 2007

By comparing the polymorphisms of Q‐banded karyotypes of a mother and her female fetus, it is possible to confirm that maternal cell contamination is a rare event in prenatal diagnosis. The frequency with which any given polymorphism is distinctive is directly correlated to its prevalence in the population. Hence, since the polymorphisms on bands 3c, 13p and 21s are the most prevalent in the population, comparison of these maternal bands with the corresponding fetal ones is most likely to yield a distinctive pattern between a mother and her female fetus. However, in light of the rarity of maternal cell contamination, comparison of chromosomal polymorphisms is not cost‐effective for all cases, and is recommended only for high‐risk situations such as prenatal diagnosis of recessive or X‐linked diseases, where maternal age is over 40, or when amniotic fluid is grossly bloody.
Ultrasound movement patterns of fetuses with chromosome anomalies
Authors: Boué J. , Vignal P. , Aubry J. P. , Aubry M. C. , Mac Aleese J.
Published: March 2007

Fetal movements were examined by ultrasound in 24 pregnancies in which an abnormal karyotype was detected in fetal cells and compared to ultrasound fetal movement patterns in normal pregnancies. The main features in fetuses with chromosome anomalies observed at 18–20 weeks of gestation are the persistence of global, jerky movements with twitches usually seen at 13–14 weeks of gestation in normal fetuses. This fetal motor behaviour is inconstant in trisomy 21. In trisomy 18 the hand deformities are easily detected.
Prenatal diagnosis of congenital adrenal hyperplasia due to 21‐hydroxylase deficiency by amniotic fluid steroid analysis
Authors: Hughes I. A. , Laurence K. M.
Published: March 2007

The concentration of 17OH‐progesterone was measured in second trimester amniotic fluid samples from 12 mothers who previously had had an infant with congenital adrenal hyper‐plasia due to 21‐hydroxylase deficiency. In 4 affected pregnancies, the concentrations were more than 2 S.D. higher than those determined in 44 samples from normal pregnancies (mean ± S.D., 8·1 ± 2·4 nmol/1). The remaining 8 pregnancies were predicted to be unaffected based on the results of amniotic fluid concentrations within the normal range. In each instance, the infant was normal. The results indicate that measurement of amniotic fluid 17OH‐progester‐one concentrations during the second trimester is an accurate prenatal test for 21‐hydroxylase deficiency. The results should be supplemented with determination of fetal sex by karyotype analysis on the amniotic fluid cells.
Amniotic fluid pregnancy‐specific β1‐glycoprotein (SP1) in Meckel's syndrome: A new test for prenatal diagnosis?
Authors: Heikinheimo Markku , Aula Pertti , Rapola Juhani , Wahlström Torsten , Jalanko Hannu , Seppälä Markku
Published: March 2007

Amniotic fluid levels of pregnancy‐specific β1‐glycoprotein (SP1) were elevated in four pregnancies with Meckel's syndrome at 16 and 26 weeks, and the levels of hCG were also elevated in three out of four cases. These findings suggest a potential new application of SP1 measurement for prenatal diagnosis.
46,XX/46,XY chromosome complement in amniotic fluid cell culture followed by the birth of a normal female child
Authors: Hunter Alasdair , Brierley Kathy , Tomkins Darrell
Published: March 2007

Experience indicates that the most likely explanation for a mixture of 46,XX/46,XY cells in an amniotic fluid sample is that of maternal cell contamination and that a normal male child is to be expected at birth. We report the birth of a normal female child following prenatal diagnosis of such a mixture. Extensive postnatal studies failed to reveal an XY cell line. The possible sources of the XY cell line are discussed, as are the various techniques that were applied in an effort to discover it's origin. Cross‐contamination of samples could be ruled out and there was no evidence of an unsuspected twin pregnancy. It is clear from this case that not all 46,XX/46,XY results obtained in amniotic fluid can be assumed to represent maternal cell contamination and some effort should be made to eliminate other potential sources for such a mixture.
A simple procedure for obtaining fetal chromosome preparations from bloodstained amniotic fluid
Authors: Watt Jessie L. , Laing Elizabeth J.
Published: March 2007

Two patients undergoing amniocentesis are described in which the resulting amniotic fluid was unavoidably bloodstained. The results suggest that it may be beneficial in such cases to reserve a small volume of bloodstained liquor for culture with phytohaemagglutinin since the presence of a few fetal lymphocytes can lead to a prenatal diagnosis within 72 h.
Prenatal detection of the autosomal dominant type of congenital hydronephrosis by ultrasonography
Authors: McCormack Michael K.
Published: March 2007

We report a family with clearly defined two generation, and probable four generation uropathy due to a congenital malformation of the genitourinary system. There appears to be variation in expression within this family and a severely affected fetus was detected by ultrasonography at 31 weeks gestation.
Sacrococcygeal teratoma: Prenatal diagnosis with elevated alphafetoprotein and acetylcholinesterase in amniotic fluid
Authors: Hecht Frederick , Hecht Barbara Kaiser , O'Keeffe Daniel
Published: March 2007

A sacrococcygeal teratoma was suspected by ultrasound examination at 24 weeks gestation. The amniotic fluid alphafetoprotein was markedly elevated, as was maternal serum AFP. Gel electrophoresis of amniotic fluid showed an acetylcholinesterase band. Labour began at 25 weeks gestation and the chromosomally normal male fetus was found to have a sacrococcygeal teratoma equal to three‐quarters of the weight of the fetus.
Separation of amniotic fluid cell types in primary culture by percoll density gradient centrifugation
Authors: Cousineau J. , Potier M. , Dallaire L. , Melanḑlon S. B.
Published: March 2007

Amniotic fluid cells obtained by transabdominal amniocentesis at 15–17 weeks of gestation and cultured for 15 and 21 days were separated into three fractions by density gradient centrifugation in Percoll. Each fraction (or peak) corresponded to the following densities: peak A, 1·02–1·03 g/ml; peak B, 1·04–1·05; peak C, 1·05–1·06. Peak A was composed of both non‐viable and viable cells; the latter adopted the morphology of epithelial cells in culture. Peak B contained a mixture of fibroblasts and epithelioid cells and peak C had only epithelioid cells. The variability of N‐acetyl‐β‐hexosaminidase and alkaline phosphatase activities was reduced in peaks B and C as compared to that of peak A and of unseparated cells suggesting that more defined and homogeneous cell types for enzymatic determinations can be obtained by centrifugation in Percoll density gradient. In prenatal diagnosis of biochemical defects, the separation of cells would permit a more precise diagnosis by eliminating enzyme variability due to the presence of different cell types or non‐viable cells.
Measurement of cholinesterases in amniotic fluid using a naphthyl acetate as substrate: A possible initial test for prenatal diagnosis of open neural tube defects
Authors: Simpson Nancy E. , Bone Miriam , Girard Kathleen
Published: March 2007

A quantitative method for cholinesterases in amniotic fluid using the non‐specific substrate α naphthyl acetate and the cholinesterase‐specific inhibitor, eserine, is described. This assay was used to test 671 samples of amniotic fluid. The diagnoses for fetal ONTDs, based on the levels of AChE + ChE, were compared with those made for the same samples by the AFP method. Correct diagnoses were made by both methods with amniotic fluid from 35 women carrying fetuses with ONTDs and 631 carrying normal fetuses. There were five false‐positive test results for normal fetuses by both methods when the cut‐off points were 5 standard deviations above the mean for AFP and above the upper limit of the normal range (7. 5 milliunits) for cholinesterase (AChE + ChE). None of the false‐positive samples from either method had the acetylcholinesterase band of activity characteristic of ONTDs after gel electrophoresis.

In addition to the above 671 samples, 37 pregnancies with serious fetal abnormalities other than ONTDs were tested. Two were identified by both the AFP and AChE + ChE methods, two more by AFP assay and one other by the AChE + ChE assay.
Prenatal diagnosis of cystic fibrosis by methylumbelliferylguanidinobenzoate protease titration in amniotic fluid
Authors: Brock David J. H. , Hayward Caroline
Published: March 2007

Amniotic fluids were obtained from 19 mothers who had previously given birth to a child with cystic fibrosis. Measurement of methylumbelliferyl guanidinobenzoate (MUGB) reactive proteases suggested that all 19 would have unaffected babies. Amongst the first 10 cases to come to term there were 5 infants with cystic fibrosis. It is concluded that MUGB protease titration is not suitable for the early prenatal diagnosis of cystic fibrosis.
Prenatal determination of dihydropteridine reductase in a normal fetus at risk for malignant hyperphenylalaninemia
Authors: Firgaira Frank A. , Cotton Richard G. H. , Danks David M. , Fowler Kerry , Lipson Anthony , Yu John S.
Published: March 2007

Assay of dihydropteridine reductase in amniotic cells from a fetus at risk for malignant hyperphenylalaninemia is described. A normal result was obtained, this was confirmed after delivery. On two‐dimensional polyacrylamide gel electrophoresis the enzyme from amniotic cells showed the same mobility as the mature liver reductase.
Alpha‐fetoprotein and ultrasound scanning in the prenatal diagnosis of Turner's Syndrome
Authors: Toftager‐Larsen K. , Benzie R. J. , Doran T. A. , Miskin M. , Allen L. C. , Becker L.
Published: March 2007

Based on data from 5 cases of fetal cystic hygroma (4 cases of Turner's Syndrome and one case of Trisomy 18) and one case of Down's Syndrome with severe subcutaneous oedema, it is concluded that amniotic fluid alpha‐fetoprotein (AFP) is normal or only slightly elevated in such cases whereas AFP in fluid from the cystic structures is very high. Reported high values of ‘amniotic fluid’ AFP are therefore likely to have been obtained from fluids accidentally drawn from the cystic structures. Fluids from the two sources cannot be distinguished from each other visually. In support of this theory is that the maternal serum AFP was found to be normal in all cases where investigated. In the diagnosis of cystic hygromata detailed ultrasound scanning will reveal the correct diagnosis.
Mid‐trimester fetal ultrasound: Diagnostic dilemmas
Authors: Corson Virginia L. , Sanders Roger C. , Johnson Timothy R. B. , Winn Kevin J.
Published: March 2007

Two cases are reported in which an unusual ultrasound finding preceded diagnostic amniocentesis and led to further work‐up. In both cases a decision was made to terminate the pregnancy. One fetus in which a neck mass was detected by ultrasound was shown to be normal on post‐mortem examination. The second fetus was aborted because of Rh sensitization and had the abnormality seen by ultrasound. However, this lesion, calcified intrahepatic plaques, had no presumed pathological significance. These cases suggest caution in the interpretation of results obtained with the new technologies used for prenatal diagnosis.