Ultrasound-guided perineal laser ablation versus prostatic arterial embolization for benign prostatic hyperplasia: two similar short-term efficacies

BACKGROUND

There are many ways to treat prostatic hyperplasia; these are currently more inclined to minimally invasive treatment. We mainly compared the differences between two treatment methods， ultrasound-guided transperineal laser ablation (US-TPLA) and prostatic artery embolization (PAE).

PURPOSE

To evaluate the efficacy and safety of US-TPLA and PAE in the treatment of benign prostatic hyperplasia (BPH).

MATERIAL AND METHODS

The clinical information for 40 patients with BPH admitted to our hospital between June 2018 and January 2021 were retrospectively analyzed. The changes in International Prostate Symptom Score (IPSS), quality of life (QoL), maximum urinary flow rate (Qmax), postvoid residual (PVR), prostate volume (PV), and the incidence of complications were compared between groups.

RESULTS

The IPSS (P < 0.001; P < 0.001), QoL (P < 0.001; P < 0.001), Qmax (P < 0.001; P < 0.001), PVR (P < 0.001; P < 0.001), and PV (P < 0.001; P < 0.001) at three and six months after US-TPLA and PAE improved with respect to those before surgery. There was no significant difference in IPSS (P = 0.235; P = 0.151), QoL (P = 0.527; P = 0.294), Qmax (P = 0.776; P = 0.420), PVR (P = 0.745; P = 0.607), and PV (P = 0.527; P = 0.573) between the groups at three and six months after surgery. No serious complications occurred in either group.

CONCLUSION

US-TPLA and PAE seem to have a similar short-term efficacy. The efficacy of the two procedures is comparable, and neither is associated with serious complications. US-TPLA and PAE are both effective complementary measures for the treatment of BPH.

Guidance on infection control and plume management with Laser and Energy-Based Devices taking into consideration COVID-19

BACKGROUND

The COVID-19 pandemic has disrupted the practice of medicine. Dermatologic laser and energy-based device (EBD) treatments carry a potential risk for the transmission of SARS-CoV-2 both for the patient and the practitioner. These risks include close practitioner to patient proximity, the treatment of higher viral load areas such as the face, the potential for infective bioparticles being carried by generated plumes and aerosols, and the direct contact between device, practitioner and patient.

OBJECTIVES

SARS-CoV-2 is a highly infective respiratory pathogen transmitted by respiratory droplets, respiratory/mucosal secretions, medically generated aerosols and via its transfer from contaminated fomites. This requires a review of the appropriateness of infection control protocols in regard to dermatologic laser and energy-based device treatments.

METHODS

A critical evaluation of patient skin preparation including skin asepsis, device disinfection, laser and electrosurgical plume management and PPE in regard to SARS-CoV-2 was performed.

RESULTS

The adherence to a high standard of skin preparation and asepsis, device disinfection, laser and electrosurgical plume and aerosol management and appropriate PPE should help mitigate or reduce some of the inherent treatment risks. Head and neck treatments along with aerosol and laser plume generating treatments likely carry greater risk.

CONCLUSIONS

COVID-19 needs to be considered in the clinic set-up along with the planning, treatment and post-treatment care of patients utilising EBD procedures. Some of these treatment precautions are COVID-19 specific; however, most represent adherence to good infectious disease and established laser and EBD safety precautions.

Laser dentistry in daily practice during the COVID-19 pandemic: Benefits, risks and recommendations for safe treatments

The COVID-19 pandemic forced dental professionals to cope with an unexpected challenge and caused an abrupt cessation of conventional care practices. The high degree of contagiousness as well as the diffusion of the virus through the air and droplets via respiratory transmission placed dental professionals at top-level risk of contracting and spreading the disease. General recommendations were announced in different countries, including patient distancing, air ventilation, surface and instrument sanitization, and the wearing of suitable masks and shields. However, many dental treatments are performed using lasers, and some specific precautions must be added to conventional procedures to ensure the advantages of this technology to patients because of the particular tissue–matter interaction effects of laser wavelengths. Based on the literature, the authors evaluated all of using laser wavelengths to analyze the risk and the benefits of using lasers in daily dental practice, and to provide safety recommendations during pandemic. An unrestricted search of indexed databases was performed. Laser use effects were categorized into: 1) explosive processes that produce tissue ablation and aerosol formation; 2) thermal actions that create vaporization and smoke plume; 3) photobiomodulation of the cells; and 4) enhanced chemical activity. Knowledge of the device functions and choice of adequate parameters will reduce aerosol and plume formation, and the application of suction systems with high flow volume and good filtration close to the surgical site will avoid virus dissemination during laser use. In the categories that involve low energy, the beneficial effects of lasers are available and sometimes preferable during this pandemic because only conventional precautions are required. Lasers maintain the potential to add benefits to dental practice even in the COVID-19 era, but it is necessary to know how lasers work to utilize these advantages. The great potential of laser light, with undiscovered limits, may provide a different path to face the severe health challenges of this pandemic.

Rationale for Use of Combination Therapy in Rosacea

BACKGROUND

Rosacea is a chronic skin condition characterized by primary and secondary manifestations affecting the centrofacial skin. The primary diagnostic phenotypes for rosacea are fixed centrofacial erythema with periodic intensification, and phymatous changes. Major phenotypes, including papules and pustules, flushing, telangiectasia, and ocular manifestations, may occur concomitantly or independently with the diagnostic features. The phenotypes of rosacea patients may evolve between subtypes and may require multiple treatments concurrently to be effectively managed. We report the proceedings of a roundtable discussion among 3 dermatologists experienced in the treatment of rosacea and present examples of rosacea treatment strategies that target multiple rosacea symptoms presenting in individual patients.

METHODS

Three hypothetical cases describing patients representative of those commonly seen by practicing dermatologists were developed. A roundtable discussion was held to discuss overall and specific strategies for treating rosacea based on the cases.

RESULTS/DISCUSSION

With few exceptions, the dermatologists recommended combination therapy targeting each manifestation of rosacea for each case. These recommendations are in agreement with the current American Acne and Rosacea Society treatment guidelines for rosacea and are supported by several studies demonstrating beneficial results from combining rosacea treatments.

CONCLUSIONS

Rosacea is an evolving condition; care should take into account all clinical signs and symptoms of rosacea that are present in an individual patient, understanding that symptoms may change over time, and utilize combination therapy when applicable to target all rosacea symptoms. J Drugs Dermatol. 2020;19(10): 929-934. doi:10.36849/JDD.2020.5367.

Computer-assisted planning for minimally invasive anterior two-thirds laser corpus callosotomy: A feasibility study with probabilistic tractography validation

•

Laser interstitial thermal therapy (LITT) is a novel minimally invasive technique for the treatment of epilepsy.

•

We test computer assisted planning with LITT to disrupt seizure spread.

•

Trajectory parameters and models were automatically generated from a single T1 image.

•

Probabilistic tractography revealed comparable interhemispheric disconnection to blinded expert surgeons.

Background

Anterior two-thirds corpus callosotomy is an effective palliative neurosurgical procedure for drug-refractory epilepsy that is most commonly used to treat drop-attacks. Laser interstitial thermal therapy is a novel stereotactic ablative technique that has been utilised as a minimally invasive alternative to resective and disconnective open neurosurgery. Case series have reported success in performing laser anterior two-thirds corpus callosotomy. Computer-assisted planning algorithms may help to automate and optimise multi-trajectory planning for this procedure.

Objective

To undertake a simulation-based feasibility study of computer-assisted corpus callostomy planning in comparison with expert manual plans in the same patients.

Methods

Ten patients were selected from a prospectively maintained database. Patients had previously undergone diffusion-weighted imaging and digital subtraction angiography as part of routine SEEG care. Computer-assisted planning was performed using the EpiNav™ platform and compared to manually planned trajectories from two independent blinded experts. Estimated ablation cavities were used in conjunction with probabilistic tractography to simulate the expected extent of interhemispheric disconnection.

Results

Computer-assisted planning resulted in significantly improved trajectory safety metrics (risk score and minimum distance to vasculature) compared to blinded external expert manual plans. Probabilistic tractography revealed residual interhemispheric connectivity in 1/10 cases following computer-assisted planning compared to 4/10 and 2/10 cases with manual planning.

Conclusion

Computer-assisted planning successfully generates multi-trajectory plans capable of LITT anterior two-thirds corpus callosotomy. Computer-assisted planning may provide a means of standardising trajectory planning and serves as a potential new tool for optimising trajectories. A prospective validation study is now required to determine if this translates into improved patient outcomes.

Laws and regulations of laser operation in the United States

The laws and regulations governing laser operation in the United States are vague, complex, and vary state-to-state. The objective of this study is to present an overview of the laws and regulations of laser operation in each of the 50 states. We performed an extensive online search of the law in each of the 50 states by examining multiple state cosmetology boards, state legislative boards, state nursing boards, and state medical boards. Laser regulations are best divided into three categories: delegation, supervision, and operation. Our findings demonstrate the complicated nature of the regulations covering this issue and identify a lack of regulation in numerous states. Lasers Surg. Med. 50:272-279, 2018. © 2018 Wiley Periodicals, Inc.

Blue diode laser versus traditional infrared diode laser and quantic molecular resonance scalpel: clinical and histological findings after excisional biopsy of benign oral lesions

This study aims to compare the use of the innovative blue diode laser (BLUE group) with two traditional surgical techniques: the infrared diode laser (IR group) and the quantic molecular resonance scalpel (QMR group) in the excision of benign oral lesions. Ninety-three patients underwent surgical excision of a benign oral lesion and were followed up for 30 days for pain (0 to 10 visual analogue scale), bleeding, and painkillers’ assumption (yes/no). A blind pathologist evaluated the thermal damage along the cutting margin. Although referred pain was lowest in the BLUE group from day 7 on (p<0.05), all patients referred minimum discomfort after surgery. The BLUE group reported minimum bleeding and necessity of sutures (p<0.000). The QMR group showed the highest bleeding during surgery (p<0.000), while after 14 and 30 days no patient bled. Most of the patients in all groups did not need painkillers. The lowest thermal damage (p<0.000) was found in the BLUE group (71.3±51.8???m), whereas the IR group proved the highest (186.8±82.7???m) compared both with the BLUE and QMR (111.4±55.4???m) groups. All the techniques allowed correct histological sampling. All the experimented techniques offer interesting advantages, although the blue laser minimizes risk of bleeding with limited thermal damage.

Femtosecond laser surgery of two-cell mouse embryos: effect on viability, development, and tetraploidization

The effect of the laser pulse energy and total expose of the energy incident on the embryo blastomere fusion probability was investigated. The probability of the four different events after laser pulse was determined: the fusion of two blastomeres with the following formation of tetraploid embryo, the destruction of the first blastomere occurs, the second blastomere conservation remains intact, the destruction and the death of both cells; two blastomeres were not fused, and no morphological changes occurred. We report on viability and quality of the embryo after laser surgery as a function of the laser energy incident. To characterize embryo quality, the probability of the blastocyst stage achievement was estimated and the blastocyst cells number was calculated. Blastocoel formation is the only event of morphogenesis in the preimplantation development of mammals, so we assumed it as an indicator of the time of embryonic "clocks" and observed it among fused and control embryos. The blastocoel formation time is the same for fused and control embryos. It indicates that embryo clocks were not affected due to blastomere fusion. Thus, the analysis of the fluorescence microscopic images of nuclei in the fused embryo revealed that nuclei fusion does not occur after blastomere fusion.

Diabetic Macular Edema: Emerging Strategies and Treatment Algorithms

Diabetic macular edema (DME) is the most common cause of vision loss in diabetic patients, and its management is often a long process requiring frequent monitoring and therapeutic interventions. During the past several decades, numerous treatments have been developed for the treatment of DME. Although many of them have been found to be effective and safe, there is relatively little comparative data, and no established guidelines for the optimal treatment approach exist. In this chapter, the evolution of DME therapies is reviewed, and the current common practice patterns are discussed. Available data from clinical trials on the commonly used agents, as well as comparative studies and combination therapies are reviewed. Additionally, recent advances and novel treatment options that are currently being investigated are also discussed.

Optical properties of animal tissues in the wavelength range from 350 to 2600 nm

The optical properties of different cow and pig biological tissues such as skeletal muscle, adipose, spinal cord, and dura mater of the spinal cord were investigated in the spectral range of 350 to 2600 nm. The measurements were carried out by a commercially available spectrophotometer SHIMADZU UV 3101PC. The wavelength dependence on the scattering coefficient has been observed to follow a power-law decay for skeletal muscle and dura mater of spinal cord. The influence of time delay between the sample preparation and measuring of transmittance spectra on the data reasonableness was reviewed. The conclusion about the benefits of 2 - ? m lasers application in surgery is given for the tissue types listed above.

A synopsis of current international guidelines and new modalities for the treatment of varicose veins

BACKGROUND

The UK National Institute for Health and Care Excellence released new guidelines in 2013 recommending that endovenous thermal ablation (laser or radiofrequency) and ultrasound-guided foam sclerotherapy should be offered before conventional surgery for treat-ment of varicose veins and saphenous vein reflux.

OBJECTIVE

The aim of this article is to provide a synopsis of current international guidelines and recent advances for the treatment of varicose veins.

DISCUSSION

Conventional surgery involving classical high ligation and stripping of the saphenous vein has been standard practice for nearly a century. Surgery requires general anaesthesia and hospitalisation, and there is a high rate of recurrent disease. In the past decade there has been an international trend where the minimally invasive techniques of endovenous thermal ablation and ultrasound-guided foam sclerotherapy, which do not require hospitalisation, are beginning to displace surgery. These changes in technique have been supported by recently published international guidelines.

Determination of scattering properties and damage thresholds in tissue using ultrafast laser ablation

Ultrafast laser surgery of tissue requires precise knowledge of the tissue’s optical properties to control the extent of subsurface ablation. Here, we present a method to determine the scattering lengths, ?s, and fluence thresholds, Fth, in multilayered and turbid tissue by finding the input energies required to initiate ablation at various depths in each tissue layer. We validated the method using tissue-mimicking phantoms and applied it to porcine vocal folds, which consist of an epithelial (ep) layer and a superficial lamina propia (SLP) layer. Across five vocal fold samples, we found ?s,ep=51.0±3.9???m, Fth,ep=1.78±0.08??J/cm2, ?s,SLP=26.5±1.6???m, and Fth,SLP=1.14±0.12??J/cm2. Our method can enable personalized determination of tissue optical properties in a clinical setting, leading to less patient-to-patient variability and more favorable outcomes in operations, such as femto-LASIK surgery.

Initial experience using a femtosecond laser cataract surgery system at a UK National Health Service cataract surgery day care centre

OBJECTIVES

To describe the initial outcomes following installation of a cataract surgery laser system.

SETTING

National Health Service cataract surgery day care unit in North London, UK.

PARTICIPANTS

158 eyes of 150 patients undergoing laser-assisted cataract surgery.

INTERVENTIONS

Laser cataract surgery using the AMO Catalys femtosecond laser platform.

PRIMARY OUTCOME MEASURE

intraoperative complications including anterior and posterior capsule tears.

SECONDARY OUTCOME MEASURES

docking to the laser platform, successful treatment delivery, postoperative visual acuities.

RESULTS

Mean case age was 67.7±10.8 years (range 29-88 years). Docking was successful in 94% (148/158 cases), and in 4% (6/148 cases) of these, the laser delivery was aborted part way during delivery due to patient movement. A total of 32 surgeons, of grades from junior trainee to consultant, performed the surgeries. Median case number per surgeon was 3 (range from 1-20). The anterior capsulotomy was complete in 99.3% of cases, there were no anterior capsule tears (0%). There were 3 cases with posterior capsule rupture requiring anterior vitrectomy, and 1 with zonular dialysis requiring anterior vitrectomy (4/148 eyes, 2.7%). These 4 cases were performed by trainee surgeons, and were either their first laser cataract surgery (2 surgeons) or their first and second laser cataract surgeries (1 surgeon).

CONCLUSIONS

Despite the learning curve, docking and laser delivery were successfully performed in almost all cases, and surgical complication rates and visual outcomes were similar to those expected based on national data. Complications were predominately confined to trainee surgeons, and with the exception of intraoperative pupil constriction appeared unrelated to the laser-performed steps.

Subsequent Receipt of Interventions for Glaucoma Among a Nationwide Sample of Patients Who Underwent Laser Peripheral Iridotomy

PURPOSE

To evaluate use of medical, laser, or incisional surgical interventions for glaucoma after laser peripheral iridotomy (LPI).

DESIGN

Retrospective longitudinal cohort study.

METHODS

All enrollees aged ≥21 years in a US managed-care network who underwent bilateral LPIs in 2001-2011 were identified. The mean numbers of pre- and post-LPI glaucoma medication classes prescribed and the proportion of enrollees requiring cataract or glaucoma surgery within 2 years after the LPIs were determined. Multivariable logistic regression assessed factors associated with enrollees' prescription of ≥1 glaucoma medication class after bilateral LPIs.

RESULTS

Of the 1660 patients undergoing bilateral LPIs, 1280 (77.1%) had no pre- or post-LPI prescriptions for any glaucoma medication class. Of the remaining patients, 251 (66.1%) required more glaucoma medication classes after than before the procedures, whereas 44 (11.6%) used fewer after the procedures; 85 (22.4%) were prescribed the same number before and after the LPIs. A total of 167 patients (10.1%) underwent cataract surgery and 79 (4.8%) received glaucoma surgery over the 2-year follow-up. Black patients had a 130% increased odds for glaucoma medication-class prescriptions after bilateral LPIs, compared with white patients (P = .02). The odds of post-LPI glaucoma medication use increased by 21% for every additional 5 years of age (P < .0001).

CONCLUSION

Most patients undergoing bilateral LPIs received no pre- or post-LPI glaucoma medication-class prescriptions and had no cataract or additional glaucoma surgery within 2 years after LPIs. Clinicians should alert black or older patients and those already taking glaucoma medications before the procedure of their higher odds of requiring medications afterward.

LASERS and the LAW: what the dermatologist needs to know

Dermatologic laser surgery is a continuously evolving field of medicine. According to the American Society for Dermatologic Surgery, over 100 million laser and light source cosmetic procedures were performed by its members in 2003. Procedures, which include hair removal, nonablative treatments, as well as removal of pigmented lesions, tattoos, and unwanted vascular lesions, have revolutionized this field. With an increasing number of physicians and nonphysicians performing these procedures and with the availability of increasingly powerful laser technologies, the potential for problems and their legal consequences continue to increase. This article will address the concept of negligence and the potential for a resultant medical malpractice lawsuit that may arise in such a setting. Inherent in this issue are the associated problems that arise when these procedures are performed by physician extenders. An understanding of the basic principals of a cause of action in medical malpractice will likely protect a physician from losing such a case in a court of law.

Tool to visualize and evaluate operator proficiency in laser hair-removal treatments

BACKGROUND

The uniform delivery of laser energy is particularly important for safe and effective laser hair removal (LHR) treatment. Although it is necessary to quantitatively assess the spatial distribution of the delivered laser, laser spots are difficult to trace owing to a lack of visual cues. This study proposes a novel preclinic tool to evaluate operator proficiency in LHR treatment and applies this tool to train novice operators and compare two different treatment techniques (sliding versus spot-by-spot).

METHODS

A simulation bed is constructed to visualize the irradiated laser spots. Six novice operators are recruited to perform four sessions of simulation while changing the treatment techniques and the presence of feedback (sliding without feedback, sliding with feedback, spot-by-spot without feedback, and spot-by-spot with feedback). Laser distribution maps (LDMs) are reconstructed through a series of images processed from the recorded video for each simulation session. Then, an experienced dermatologist classifies the collected LDMs into three different performance groups, which are quantitatively analyzed in terms of four performance indices.

RESULTS

The performance groups are characterized by using a combination of four proposed indices. The best-performing group exhibited the lowest amount of randomness in laser delivery and accurate estimation of mean spot distances. The training was only effective in the sliding treatment technique. After the training, omission errors decreased by 6.32% and better estimation of the mean spot distance of the actual size of the laser-emitting window was achieved. Gels required operators to be trained when the spot-by-spot technique was used, and imposed difficulties in maintaining regular laser delivery when the sliding technique was used.

CONCLUSIONS

Because the proposed system is simple and highly affordable, it is expected to benefit many operators in clinics to train and maintain skilled performance in LHR treatment, which will eventually lead to accomplishing a uniform laser delivery for safe and effective LHR treatment.

[European Association of Urology guidelines on laser technologies]

CONTEXT

The European Association of Urology (EAU) Guidelines Office has set up a guideline working panel to analyse the scientific evidence published in the world literature on lasers in urologic practice.

OBJECTIVE

Review the physical background and physiologic and technical aspects of the use of lasers in urology, as well as current clinical results from these new and evolving technologies, together with recommendations for the application of lasers in urology. The primary objective of this structured presentation of the current evidence base in this area is to assist clinicians in making informed choices regarding the use of lasers in their practice.

EVIDENCE ACQUISITION

Structured literature searches using an expert consultant were designed for each section of this document. Searches were carried out in the Cochrane Database of Systematic Reviews, the Cochrane Central Register of Controlled Trials, and Medline and Embase on the Dialog/DataStar platform. The controlled terminology of the respective databases was used, and both Medical Subject Headings and EMTREE were analysed for relevant entry terms. One Cochrane review was identified.

EVIDENCE SYNTHESIS

Depending on the date of publication, the evidence for different laser treatments is heterogeneous. The available evidence allows treatments to be classified as safe alternatives for the treatment of bladder outlet obstruction in different clinical scenarios, such as refractory urinary retention, anticoagulation, and antiplatelet medication. Laser treatment for bladder cancer should only be used in a clinical trial setting or for patients who are not suitable for conventional treatment due to comorbidities or other complications. For the treatment of urinary stones and retrograde endoureterotomy, lasers provide a standard tool to augment the endourologic procedure.

CONCLUSIONS

In benign prostatic obstruction (BPO), laser vaporisation, resection, or enucleation are alternative treatment options. The standard treatment for BPO remains transurethral resection of the prostate for small to moderate size prostates and open prostatectomy for large prostates. Laser energy is an optimal treatment method for disintegrating urinary stones. The use of lasers to treat bladder tumours and in laparoscopy remains investigational.

[Role of optical properties of the venous wall for endovenous laser obliteration]

Presented herein are the results of studying the optical density of water, blood, and venous-wall tissue for various-wavelength laser radiation, with determining the peaks of absorption of radiation by the above-mentioned media. The absorption peaks in water and blood correspond to wavelengths of 1,450 and 1,935 nm, respectively. Peaks of absorption in the venous-wall tissue are within the intervals equaling 650-950 nm, 1,445-1,455 nm, and more than 1,900 nm. Also determined was the optical density of the veins for the most frequently used in clinical practice wavelengths, i. e. 1,030 and 1,470 nm, with the calculation of the portion of the absorbed energy depending on thickness of the layer of the absorbing substance. Based on the obtained findings, a conclusion was drawn on better utilization of the energy of one-and-a-half-micron range laser radiation and on its preferable use for endovenous laser obliteration (EVLO).

Kalman filtered MR temperature imaging for laser induced thermal therapies

The feasibility of using a stochastic form of Pennes bioheat model within a 3-D finite element based Kalman filter (KF) algorithm is critically evaluated for the ability to provide temperature field estimates in the event of magnetic resonance temperature imaging (MRTI) data loss during laser induced thermal therapy (LITT). The ability to recover missing MRTI data was analyzed by systematically removing spatiotemporal information from a clinical MR-guided LITT procedure in human brain and comparing predictions in these regions to the original measurements. Performance was quantitatively evaluated in terms of a dimensionless L(2) (RMS) norm of the temperature error weighted by acquisition uncertainty. During periods of no data corruption, observed error histories demonstrate that the Kalman algorithm does not alter the high quality temperature measurement provided by MR thermal imaging. The KF-MRTI implementation considered is seen to predict the bioheat transfer with RMS error < 4 for a short period of time, ∆t < 10 s, until the data corruption subsides. In its present form, the KF-MRTI method currently fails to compensate for consecutive for consecutive time periods of data loss ∆t > 10 sec.

Injury depth control from combined wavelength and power tuning in scanned beam laser thermal therapy

Laser thermal therapy represents a possible method to treat premalignant epithelial lesions of the esophagus. Dynamically conforming the thermal injury profile to a specific lesion boundary is expected to improve the efficacy of such a treatment and avoid complications. In this work, we investigated wavelength tuning as a mechanism to achieve this aimed control over injury depth by using the strong variation of water absorption close to 1900 nm. We developed a numerical model simulating in steps the photon propagation in the tissue, the diffusion of the absorbed heat, and the resulting tissue damage. The model was compared with experimental results on porcine esophageal specimens ex vivo and showed good agreement. Combined with power tuning, the wavelength agility in the range of 1860 to 1895 nm extends the injury range compared to a fixed wavelength source beyond 1 mm, while at the same time improving control over shallow depths and avoiding vaporization at the tissue surface. The combination of two or three discrete wavelengths combined at variable ratios provides similar control, and may provide an improved strategy for the treatment of endothelial lesions.

Use of eye shields and eye lubricants among oculoplastic and Mohs surgeons: a survey

BACKGROUND

Eye shields and lubricants are recommended for use in the eye during periorbital surgery to prevent injury to the globe. Nonetheless, data regarding their use is sparse, and no study to date has examined the prevalence of their usage and complications.

PURPOSE

To investigate how commonly eye shields and lubricants are used during periorbital surgery and whether there are complications from their use.

METHODS

The authors conducted a survey of oculoplastic and Mohs surgery fellowship directors. The questionnaire investigated the prevalence of use of eye shields and lubricants, complications encountered, and whether the standard of care requires or prohibits their use.

RESULTS

A majority of those surveyed at least sometimes use eye shields in periorbital surgery, particularly to prevent patient injury. Most surgeons believe there are more pros than cons to their use. However, corneal abrasions may be encountered and may be related to the type of lubricant chosen. Surgeons using fat-based lubricants tended to encounter more complications with eye shield use.

CONCLUSION

Eye shield and lubricant use is common among oculoplastic and Mohs surgeons. However, most disagree as to whether the standard of care requires or forbids their use.

[Endocanalicular dacryocystorhinostomy (E-DCR): relevance of materials standardization for outcomes]

INTRODUCTION AND OBJECTIVES

After 5 years' experience with endocanalicular dacryocystorhinostomy (E-DCR) using diode laser, the introduction of new materials has led to significant technical differences, thus giving rise to this study to evaluate them.

MATERIAL AND METHOD

We compare the behaviour of 2 different kinds of laser guide fibre (silica-fluoropolymer-tefzel and silica-silica-polyamide), using the same laser generator, on organic tissues from fresh animal carcases, and we summarize the clinical behaviour of the new materials in lachrymal surgery cases.

RESULTS

We have seen significant differences in the clinical behaviour of the two kinds of laser guides, namely the proposed new materials have a worse behaviour on organic tissues than their physical characteristics might theoretically have suggested. Thus, the use of different guide materials could lead to relevant differences in terms of surgical results, as well as in the comparison of the outcomes of series performed by different surgeons.

CONCLUSIONS

It is necessary to determine standards for the materials recommended for this surgery, not only for easier technical performance and better effectiveness, but also to allow comparison of results from different authors.

Construction of a standard test assembly for controlled laser studies in tissues: preliminary study on human bone material

The aim of the study is the construction of a test assembly, which facilitates objective, comparative studies on the cutting performance of lasers in hard tissue. To ensure the applicability of our own construction for the reproducible performance of laser incisions in hard tissue, eleven freshly extracted blocks (2x1.5 cm2) of human bone were prepared with a Er,Cr:YSGG laser by using a handheld handpiece, respectively, using the constructed device for a standardized cutting. A total of 44 cuts were executed. The specimen were then histologically evaluated. The standard test assembly met the requirements concerning the provision of objective results. The findings of the histological evaluation prove the reproducibility of the results. The standard test assembly presented in this paper facilitates comparative studies of different laser systems by reducing subjective influence on the preparation to a minimum. The results of this preliminary study show that the precision of the guiding instrument for laser cutting reduces the error of cut width by 50-fold, from 50 to 1 microm.

Standardisation of Parameters during Endovenous Laser Therapy of Truncal Varicose Veins - Experimental Ex-vivo Study

BACKGROUND

Vein shrinkage is a surrogate marker for successful laser treatment of varicose veins. However, many controversies still remain concerning the best laser parameters to use. The aim of this study was standardisation of intraoperative energy dosages and pull-back rates to achieve optimal clinical results.

DESIGN

Ex-vivo study in surgically removed saphenous trunks.

MATERIAL AND METHODS

Great saphenous veins were removed by Babcock stripping and irradiated with laser energy delivered by a laser diode emitting at 980 nm. In total, 279 vein segments (5 cm long) were treated using powers from 5-15 W. Vein segments were opened longitudinally and the circumference measured in the treated and untreated regions to assess thermal shrinkage.

RESULTS

The greatest shrinkage and minimum number of perforations was achieved using lower or medium power (8 to 12 W) with longer exposure to administer laser energy. The median percentage vein shrinkage was 50% (power 5 W), 45% (8 W), 40% (10 W), 45% (12 W) and 59% (15 W). When a higher power was used (15 W), the perforations were more frequent and carbonisation was marked.

CONCLUSIONS

Our data suggests that similar efficacy with fewer vein perforations may be obtained with low or medium power settings and increased exposure when undertaking laser obliteration of saphenous trunks. This may result in fewer adverse events such as ecchymosis following treatment in patients.

Peri-operative complications of holmium laser enucleation of the prostate: experience in the first 280 patients, and a review of literature

OBJECTIVE

To evaluate, in a prospective study, the complications in 280 patients undergoing holmium laser enucleation of the prostate (HoLEP) at our institution, and to review previous reports to determine the overall incidence and types of various complications, and analyse their causes and means of prevention.

PATIENTS AND METHODS

We analysed the patients' demographic, peri-operative and follow-up data, and the complications during and after surgery.

RESULTS

HoLEP was completed successfully in 268 patients (95.7%); eight required conversion to transurethral resection of the prostate (TURP) during the initial experience. The morcellation device and laser malfunctioned in two patients each. A blood transfusion was required during HoLEP in one patient; other complications included capsular perforation (9.6%), superficial bladder mucosal injury (3.9%) and ureteric orifice injury (2.1%). A blood transfusion was needed after HoLEP in 1.4% of patients and cystoscopy with clot evacuation in 0.7%. Transient urinary incontinence was the commonest complication after HoLEP, in 10.7% of patients, but recovered spontaneously in all except two (0.7%). Other rare complications were re-catheterization (3.9%), urinary tract infection (3.2%), epididymitis (0.7%), meatal and submeatal stenosis (2.5%), bulbar urethral stricture (2.1%), bladder neck contracture (0.35%) and myocardial infarction (0.35%).

CONCLUSIONS

There was a low incidence of complications with HoLEP; most were minor and easily managed. Our results are comparable with those published previously, and establish HoLEP as safe and reproducible procedure. While gaining experience, HoLEP can be converted to TURP with no harm to the patient.

Use of cutaneous lasers and light sources: appropriate training and delegation

In recent years, there has been increasing concern among physicians, patient advocacy groups, and media watchdogs that laser, light, and cosmetic surgery are being practiced by poorly trained professionals, with resulting preventable injuries to patients. In response, several professional organizations have developed guidelines for the delegation of laser services to nonphysician providers. These guidelines delineate appropriate qualifications for delegating physicians and nonphysician providers, and also describe the circumstances and settings in which delegation is appropriate.

Photoselective vaporization of the prostate with the potassium-titanyl-phosphate laser in men with prostates of >100 mL

OBJECTIVES

To assess the efficacy of photoselective vaporization of the prostate (PVP) in men with prostates of >100 mL and causing bladder outlet obstruction (BOO), using the high-power 80 W potassium-titanyl-phosphate laser (GreenLight PV, Laserscope, San Jose, CA, USA), which offers rapid tissue ablation with minimal bleeding.

PATIENTS AND METHODS

We assessed 54 consecutive patients with prostates of >100 mL (mean 135, SD 42, range 100-300) who had PVP between May 2003 and August 2005. Evaluations before PVP included urine flowmetry, the International Prostate Symptom Score (IPSS), a quality-of life (QoL) score, prostate-specific antigen (PSA) level, and prostate volume measured by transrectal ultrasonography (TRUS).

RESULTS

The mean (SD, range) duration of PVP was 81.6 (22.9, 39-150) min, the mean energy used for PVP was 278 (60, 176-443) kJ and the mean duration of catheterization after PVP was 23.0 (17.1, 0-72) h. The mean (sd) maximum urinary flow rate improved from 8.0 (3.1) to 18.2 (8.1), 18.5 (9.2), 17.9 (7.8) and 19.3 (9.8) mL/s at 3, 6, 12 and 24 months, respectively. The IPSS and QoL scores showed similar improvements, and there was a statistically significant reduction in PSA level and prostate volume after PVP. There was no major complication and no patient had transurethral resection syndrome or a blood transfusion.

CONCLUSIONS

The 80 W KTP laser PVP offers rapid tissue ablation in patients with BOO caused by a large prostate. The short- and medium-term outcomes show that this technique can be a viable alternative to open prostatectomy.

[Transcanalicular laser-assisted dacryocystorhinostomy: initial results]

PURPOSE

To describe the technique and initial results of laser-assisted dacryocystorhinostomy performed through the canaliculi.

METHODS

Ten patients with nasolacrimal duct obstruction underwent transcanalicular laser-assisted dacryocystorhinostomy. A silicone tube was inserted through the canaliculi and the ostium into the nasal cavity where it will be kept for 6 months.

RESULTS

All ten operations were performed without negative occurrences. One patient presented displacement of the silicone tube one day after surgery. Nine of the ten patients reported disappearance of epiphora at the end of the first week following surgery. During the first month, one of these patients presented with epiphora due to obstruction of the lacrimal-nasal fistula and another lost the silicone tube in the first month following surgery.

CONCLUSIONS

Transcanalicular laser-assisted dacryocystorhinostomy is a potentially useful method to perform dacryocystorhinostomy.

Legal issues in laser operation

Dermatologic laser surgery is a continuously evolving field of medicine. According to the American Society for Dermatologic Surgery, in 2003, more than 100 million laser and light source cosmetic procedures were performed by its members. Procedures including hair removal and nonablative treatments, as well as removal of pigmented lesions, tattoos, and unwanted vascular lesions have revolutionized this field. With an increasing number of physicians and nonphysicians performing these procedures and with the availability of increasingly powerful laser technologies, the potential for problems and their legal consequences continue to increase. This chapter will deal with the concept of negligence and the potential for a resultant medical malpractice that may arise in such a setting. Inherent in this issue are the associated problems that arise when these procedures are performed by physician extenders. An understanding of the basic principals of a cause of action in medical malpractice will likely protect a physician from losing such a case in a court of law. The impact of the physician-physician extender relationship and the legal issues that arise from this relationship will also be discussed.

Laser in dermatology

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

Radiophonosurgery of benign superficial vocal fold lesions

Objective: To conduct a prospective randomized controlled trial describing and investigating the efficacy and safety of radiosurgical excision of benign superficial vocal fold lesions.

Materials and methods: Fifty patients with benign superficial vocal fold lesions (20 vocal nodules, 27 vocal polyps and three Reinke’s oedema) who failed conservative therapy were included in the study. They were equally randomized into cold knife or radiosurgical excision. Clinical and voice assessments were done pre-operatively and after surgery. Voice analysis included a subjective visual analogue scale (VAS) and a perceptual assessment with a simplified version of the GRBAS scale (GRB) consisting of G (grade), R (roughness), and B (breathiness). Acoustic voice evaluation included jitter and shimmer. Post-operative voice therapy was provided for all patients. Complications, smoothness of post-operative recovery, and administration of analgesia were reported.

Results: Both groups experienced significant improvement in VAS, perceptual evaluation and acoustic analysis after surgery, with no evidence of significant differences between the cold knife and radiofrequency groups. The radiofrequency group showed a decrease of 17 per cent in the mean operative time when compared with the cold knife group, but this was not statistically significant. No evidence of a significant difference was noticed in the smoothness of post-operative recovery, administration of analgesia and complication rate.

Conclusion: Radiophonosurgery opens a new therapeutic approach for patients with benign superficial vocal fold lesions. It combines the advantages of both cold knife and laser phonosurgery, being easy, safe, precise and effective, and having excellent tactile and haemostatic properties.

[Current status of standard and endovascular varicosity surgery]

The classical varicose vein operation represents the "gold standard" in the operative approach to this condition. The results of the standard procedure are very good especially with regard to complications. The recurrence rate is estimated between 6% and 60%, but the true rate is unknown, since there is no generally accepted definition of recurrent varicosities. Endovascular procedures for the elimination of the superficial venous system - radiofrequency obliteration and laser therapy - have established themselves as alternative, minimal invasive procedures. Good results up to 2 years post operatively have been documented; for radiofrequency obliteration, very good results 5 years after surgery are available. Less well-known procedures are available, such as the CHIVA method, which represents a totally different pathophysiological concept. Data on the efficacy of this method are limited, making an evaluation difficult. The spectrum of operative treatment methods of the superficial venous system and its side branches has increased tremendously because of new technical developments. The surgeon must inform the patient about the pros and cons of each procedure and the anticipated results, as well as making an accurate decision as to which methods are best suited for the patient.

Standardized Analyses of Correction of Astigmatism by Laser Systems That Reshape the Cornea

PURPOSE

To develop a minimum set of analyses and a format for presentation of outcomes of astigmatism correction by laser systems that reshape the cornea.

METHODS

An Astigmatism Project group was created under the auspices of the American National Standards Institute (ANSI) Z80.11 Working Group on Laser Systems for Corneal Reshaping. The Astigmatism Project Group was made up of experts in astigmatism analyses from academia, government, and industry. An extensive literature review was conducted to identify all currently available methodologies for the evaluation of astigmatic outcomes. Project Group members discussed the utility of each method and its specific parameters for evaluating the effectiveness of astigmatism-correcting devices. They gave consideration to unique terminology and analyses required for evaluation of correction of astigmatism by laser systems that reshape the comea.

RESULTS

The Project Group defined a comprehensive list of analysis variables needed for the evaluation of astigmatism-correcting devices and generated a mathematical definition for each term. They developed a minimum set of analyses needed for evaluation of astigmatism treatments by laser systems that reshape the cornea. They established methods for calculating the refractive error analysis variables and constructed recommended table and graph formats for data presentation.

CONCLUSIONS

This article contains the recommendations of the Astigmatism Project Group of the American National Standards Institute. We propose it as a standard reference for astigmatic refractive error analyses for the evaluation of safety and effectiveness of laser systems that reshape the cornea.

Holmium laser enucleation of the prostate: a size-independent new "gold standard"

We report our experience with holmium laser enucleation of the prostate (HoLEP) for treatment of 552 patients with symptomatic benign prostatic hyperplasia (BPH) and their long-term outcome. Between March 1998 and January 2005, a retrospective review was conducted at our institution of 552 cases in which patients underwent HoLEP. Patient characteristics, indications for surgery, preoperative and postoperative International Prostate Symptom Score (I-PSS), peak flow rate (Qmax), postvoid residual urine, operative data, catheterization time, hospital stay, and immediate and long-term complications were recorded. The mean age of patients was 73.7 +/- 7.9 years, and the mean follow-up time was 36 months. The mean preoperative prostate size was 83.7 +/- 49.7 cm3 (range, 20 to 351 cm3), the mean enucleation time was 86 minutes (range, 15 to 255 minutes), and the mean enucleated tissue weight was 52.1 +/- 43.7 g (range, 5 to 340 g). The voiding parameters were significantly improved, with a 200% increase in Qmax, as well as a 75% improvement in I-PSS at 1 year postoperatively, which continued to improve during subsequent follow-up. A total of 11 patients required blood transfusion; 8 of them were on anticoagulant therapy. Irritative symptoms were noted in 9.4% and transient stress incontinence in 4.2% of patients. Bladder neck contracture and urethral stricture each developed in 1.3% of patients. We conclude that HoLEP is a safe and effective procedure for treatment of symptomatic BPH, regardless of prostate size, with low morbidity and short hospital stay. HoLEP appears to be the modern alternative to transurethral resection of the prostate and open prostatectomy, and it may be considered a size-independent new "gold standard."