Laser interstitial thermotherapy (LiTT) in pediatric epilepsy surgery.

Laser interstitial thermotherapy (LiTT) is a novel stereotactic approach to the surgical treatment of severe drug-resistant focal epilepsies. This review extends our recent general review on this topic (Hoppe et al. Laser interstitial thermotherapy [LiTT] in epilepsy surgery. Seizure 2017; 48:45-52) with a focus on children (age <18 years). A PubMed search retrieved 25 uncontrolled case series reports that included a total of 179 pediatric patients as well as 7 review papers that specifically referred to using LiTT in pediatric epilepsy surgery (due August 31, 2018). Hypothalamic hamartomas (HH) represented the most frequent indication (64.2%) while therapeutic evidence for other more frequent etiologies underlying severe focal childhood epilepsies (e.g. focal cortical dysplasia, mesiotemporal sclerosis) is still scarce (n<20). For the published cases, the rate of severe complications was 3.4% and the overall complication rate was 23.5%. The seizure freedom rate (Engel class 1) was 57.5% (including patients with early follow-up and repeat thermoablations). None of the studies included the systematic evaluation of the cognitive outcome. Overall, the published evidence does not yet allow a scientific or clinical judgement on the utility of LiTT for pediatric epilepsy surgery. LiTT is likely to extend the neurosurgical toolbox with regard to deep brain lesions (e.g. HH). However, in cases that are equally accessible for both approaches therapeutic superiority of LiTT over open resective surgery still remains to be demonstrated. Recommendations for controlled though non-randomized outcome studies are provided.

Error traps in fetal surgery.

The growth of the field of fetal surgery over the last two decades driven by new indications and data from prospective randomized trials supporting prenatal intervention has resulted in techniques protocols and methodologies that have gained confidence by insuring good outcomes. Error traps are methods or techniques that usually work well in most of the cases, but which are apt to fail under certain specific circumstances. The very confidence the surgeon develops in these techniques or methodologies makes them a trap for the unwary surgeon. The purpose of this article is to discuss common error traps in fetal interventions, including ultrasound guided procedures, fetoscopic surgery, open fetal surgery and EXIT procedures. Awareness of these error traps and approaches to avoid them may enhance fetal surgical outcomes and reduce complications rates.

Literature review informs clinical guidelines for pain management during screening and laser photocoagulation for retinopathy of prematurity.

AIM: The aim of this study was to carry out a literature review and develop clinical guidelines for pain prevention and control during screening and laser photocoagulation for retinopathy of prematurity (ROP) in neonatal intensive care units (NICUs). METHODS: The Italian Society of Neonatology assessed papers published between 1986 and June 2017 and used the Grading of Recommendations, Assessment, Development and Evaluation approach, to develop new guidelines on pain and ROP. RESULTS: The Society's pain experts assessed the full texts of 47 papers, including randomised or quasi-randomised controlled trials and case-control studies on nonpharmacological and pharmacological measures used in NICUs during the screening and laser photocoagulation of neonates for ROP. The literature suggested methods for reducing the stress and pain associated with ROP screening procedures. The panel concluded that the literature showed that it was feasible to provide laser photocoagulation for ROP in spontaneously breathing patients with adequate analgesia. CONCLUSION: This literature review on managing pain in infants with ROP in NICUs led to the development of national guidelines, which will help physicians and nurses to reduce the stress and pain experienced by premature newborn infants during unavoidable screening and treatment for ROP.

[Diagnosis, treatment and monitoring of diabetic eye control]. / Diagnose, Therapie und Verlaufskontrolle der diabetischen Augenerkrankung.

Diabetes mellitus can cause diabetic retinopathy, diabetic macular edema, optic neuropathy, cataract or dysfunction of the eye muscles. The incidence of these defects correlates with disease duration and quality of metabolic control. Recommendations of the Austrian Diabetes Association for diagnosis, therapeutic procedures and requirements for adequate follow up depending on stage of diabetic eye disease are summarized.

Experience with the Pascal® photocoagulator: an analysis of over 1,200 laser procedures with regard to parameter refinement.

AIM: To systematically refine and recommend parameter settings of spot size, power, and treatment duration using the Pascal® photocoagulator, a multi-spot, semi-automated, short-duration laser system. MATERIALS AND METHODS: A retrospective consecutive series with 752 Caucasian eyes and 1242 laser procedures over two years were grouped into, (1) 374 macular focal / grid photocoagulation (FP), (2), 666 panretinal photocoagulation (PRP), and (3) 202 barrage photocoagulation (BP). Parameters for power, duration, spot number, and spot size were recorded for every group. RESULTS: Power parameters for all groups showed a non-gaussian distribution; FP group, median 190 mW, range 100 - 950 mW, and PRP group, median 800 mW, range 100 - 2000 mW. On subgroup comparison, for similar spot size, as treatment duration decreased, the power required increased, albeit in a much lesser proportion than that given by energy = power x time. Most frequently used patterns were single spot (89% of cases) in FP, 5 Χ 5 box (72%) in PRP, and 2 Χ 2 box (78%) in BP. Spot diameters as high as ≈ 700 µm on retina were given in the PRP group. Single session PRP was attempted in six eyes with a median spot count of 3500. CONCLUSION: Overall, due to the small duration of its pulse, the Pascal® photocoagulator tends to use higher powers, although much lower cumulative energies, than those used in a conventional laser. The consequent lesser heat dissipation, especially lateral, can allow one to use relatively larger spot sizes and give more closely spaced burns, without incurring significant side effects.

[Surgical strategy for iatrogenic injuries of the spleen].

A retrospective investigation of 1226 case histories of patients operated on the stomach and duodenum was made. Organ-saving operations using laser technique were assessed. The main cause of injuries to the spleen during operation was traction of the stomach when mobilizing it. The performance of organ-saving operations for such injuries using laser technique is possible in 76% of cases.

The use of argon laser punctal stenosis in patients with contact lens-induced dry eyes.

OBJECTIVE: To determine the efficacy of argon laser punctal stenosis inpatients with contact lens-induced dry eyes. METHODS: A retrospective review of 25 eyes of 13 patients who underwent argon laser punctal stenosis to improve their contact lens intolerance was performed. The mean age was 31 (range, 21-52) years and 11 patients (85%) were women. The mean Schirmer I test was 15.2 (range, 3-35). RESULTS: All patients tolerated the procedure well. In 19 eyes, the treatment involved only the lower punctum, whereas in six eyes, it involved both the upper and lower puncta. Eight patients required more than one treatment session (range, 2-6). At follow-up after 6 months, 10 of the 13 (77%) patients reported a substantial improvement in their symptoms and contact lens wear time. CONCLUSIONS: Argon laser punctual stenosis provides a useful and titratable treatment of contact lens intolerance due to dry eyes.

Why do patients still require surgery for the late complications of Proliferative Diabetic Retinopathy?

AIM: To briefly review and discuss the literature on why patients still require surgery for the late complications of proliferative diabetic retinopathy (PDR). METHODS: Literature review. RESULTS: The reasons for incomplete coverage of screening and screening failures can be divided into non-modifiable and potentially modifiable risk factors. The non-modifiable group includes duration of diabetes, age, genetic predisposition, ethnic differences, and the various reasons for vitrectomy when optimum laser treatment has been applied at the appropriate stage of the disease process. The potentially modifiable group includes glycaemic control, blood pressure control, lipid control, and cessation of smoking in type 1 diabetes. Other potentially modifiable factors include adequacy of screening, including reaching the regular non-attender, and attempting to modify the psychological factors that lead to late presentations including depression and eating disorders. Other potentially modifiable risk factors are optimising laser treatments and the potential use of anti-VEGF therapy to prevent vitrectomy in iris neovascularisation and neovascular glaucoma. CONCLUSION: Surgery for the late complications of PDR continues to be required even in some patients who have received optimal medical care and optimal laser treatment. There are certain modifiable risk factors that could be altered and further research is needed in specific fields, particularly with regard to the adequacy of laser treatments, the use of anti-VEGF agents in iris neovascularisation, and in the role of psychological support in reducing the type of late complications leading to surgery for PDR.

[Revised guideline 'Diabetic retinopathy: screening, diagnosis and treatment']. / Richtlijn 'diabetische retinopathie: screening, diagnostiek en behandeling' (herziening).

The revised evidence-based guideline 'Diabetic retinopathy: screening, diagnosis and treatment' contains important recommendations concerning screening, diagnosis and treatment of diabetic retinopathy. Regular screening and the treatment of risk factors, such as hyperglycemia, hypertension, adipositas and dyslipidemia, can prevent retinopathy and slow down its development. Fundus photography is recommended as a screening method. If necessary, diagnosis by biomicroscopy and a treatment consisting of photocoagulation and/or vitrectomy should be performed by the ophthalmologist. The reassessment of responsibilities is a vital component of the implementation of the guideline bearing in mind that the screening in particular, can be performed by personnel other than ophthalmologists.

Accident analysis: factors contributing to a ureteric injury during deep endometriosis surgery.

OBJECTIVE: To analyse factors associated with a ureteric injury. DESIGN: Retrospective accident analysis. SETTING: Deep endometriosis surgery in a tertiary referral centre. SAMPLE: Video recording of a surgical accident was analysed by six gynaecologists. METHODS: A 26-year-old woman underwent laparoscopy for deep endometriosis that involves the rectosigmoid and left ureter. Post operatively left ureter transection was identified and corrected by laparoscopy. Interventions were recorded and reviewed independently. MAIN OUTCOME MEASURES: Changes in surgical behaviour that could be measured were identified using the video recording. Results During the intervention, the periods of uncontrolled bleeding (P < 0.0001) and the duration of laser activation (P = 0.013) increased progressively. Simultaneous laser activation and bipolar coagulation only occurred at the end of surgery (seven episodes). Fatigue could not be measured. CONCLUSION: Unconscious acceleration of surgery, possibly as a consequence of fatigue, is suggested as a contributing factor for an error of judgement.

[Transscleral infrared laser retinal photocoagulation experimental study under low visibility conditions]. / Estudo experimental da aplicação retiniana do laser infravermelho via transescleral sob condições de baixa visibilidade.

PURPOSE: Retinal photocoagulation under poor visualization condition is often required. Transscleral infrared laser can be used as an alternative to regular transpupillary treatment. Based upon retinographic measurements, we proposed to estimate the reproducibility as well as ocular wall permeability rate for this treatment. Our primary goal was to evaluate whether this technique can deliver adequate photocoagulation at predetermined parameters without direct retinal visualization. METHODS: In New Zealand pigmented rabbits, optimal transscleral infrared diode laser settings were administered to the right eye. With the same parameters, transpupillary photocoagulation was repeated in the left eye. Retinographic and clinical examinations were performed immediately and two months later. RESULTS: Ocular wall permeability rate varied between 58.95 and 63.87%. Average permeability using a power of 300 mW (63.14%) was found to be higher than that encountered before its enhancement up to 500 mW (59.11%), (P<0.05). CONCLUSIONS: Setting parameters showed dose-response effect. No retinal hole or retinal detachment was noticed in any rabbit. Transscleral infrared photocoagulation appeared to be a reproducible and secure method in the experimental model.

Estudo experimental da aplicação retiniana do laser infravermelho via transescleral sob condições de baixa visibilidade / Transscleral infrared laser retinal photocoagulation experimental study under low visibility conditions

OBJETIVOS: Pesquisa experimental, com laser de diodo infravermelho, para estimar a segurança, a reprodutibilidade e a permeabilidade da parede ocular à sua atuação clínica, quando aplicado via transescleral, em condições de baixa visibilidade. MÉTODOS: Submetemos olhos de coelhos pigmentados da raça Nova Zelândia à fotocoagulação retiniana por laser de diodo infravermelho. No olho direito, realizamos fotocoagulação via transescleral sob parâmetros de potência e tempo pré-determinados clinicamente. No olho esquerdo, foram repetidos os mesmos valores da potência e tempo usados no olho direito, desta vez, via transpupilar. Imediatamente e após 2 meses, estudos clínicos baseados na retinografia e histopatológicos foram realizados. RESULTADOS: A permeabilidade da parede ocular, quando da aplicação do laser de diodo infravermelho via transescleral, variou entre 58,95 e 63,87 por cento. A média da permeabilidade da parede ocular a 300 mW (63,14 por cento) mostrou-se significativamente superior àquela da permeabilidade da parede ocular encontrada a 500 mW (59,11 por cento), (P<0,05). CONCLUSÕES: Este estudo sugere a existência da relação dose-resposta em relação aos parâmetros empregados na aplicação do laser de diodo infravermelho via transescleral, com permeabilidade da parede ocular mensurável e reprodutível. Nenhuma rotura, hemorragia ou descolamento da retina ou vítreo foi constatado aos exames subseqüentes às aplicações do laser de diodo infravermelho, o que torna o uso da fotocoagulação via transescleral, no modelo experimental, seguro, mesmo sob condições de baixa visibilidade dos meios.

PURPOSE: Retinal photocoagulation under poor visualization condition is often required. Transscleral infrared laser can be used as an alternative to regular transpupillary treatment. Based upon retinographic measurements, we proposed to estimate the reproducibility as well as ocular wall permeability rate for this treatment. Our primary goal was to evaluate whether this technique can deliver adequate photocoagulation at predetermined parameters without direct retinal visualization. METHODS: In New Zealand pigmented rabbits, optimal transscleral infrared diode laser settings were administered to the right eye. With the same parameters, transpupillary photocoagulation was repeated in the left eye. Retinographic and clinical examinations were performed immediately and two months later. RESULTS: Ocular wall permeability rate varied between 58.95 and 63.87 percent. Average permeability using a power of 300 mW (63.14 percent) was found to be higher than that encountered before its enhancement up to 500 mW (59.11 percent), (P<0.05). CONCLUSIONS: Setting parameters showed dose-response effect. No retinal hole or retinal detachment was noticed in any rabbit. Transscleral infrared photocoagulation appeared to be a reproducible and secure method in the experimental model.

[Visual stability in diabetic retinopathy treated by panretinal laser photocoagulation]. / Estabilidade visual na retinopatia diabética tratada por panfotocoagulação com laser.

PURPOSE: To evaluate the effect of laser treatment in the visual acuity caused by advanced diabetic retinopathy without visual complaints. METHODS: A descriptive observational study was developed in advanced diabetic retinopathy patients not presenting visual complaints. The patients were submitted to argon laser panretinal photocoagulation after ophthalmological examination as well as retinography and retinal angiofluoresceinography. The same initial exams were repeated between third and fifth months after the treatment. The non-parametric Wilcoxon test was employed for statistical evaluation between the visual acuities before and after the treatment. RESULTS: The sample involved 67 eyes of 44 patients. Of these 67 eyes, 37 (55.2%) presented proliferative diabetic retinopathy and 30 (44.8%) showed severe and severe non proliferative diabetic retinopathy. The visual acuity before the treatment ranged from 0.5 to 1.0 (mean 0.81 +/- 0.16). There was no significant statistical difference between the visual acuity (p= 0.057) before and after the treatment during the follow-up period of five months. CONCLUSION: The visual stability after panretinal argon laser photocoagulation indicated the need of this treatment in early phases of diabetic retinopathy in order to preserve the visual function.

Estabilidade visual na retinopatia diabética tratada por panfotocoagulação com laser / Visual stability in diabetic retinopathy treated by panretinal laser photocoagulation

OBJETIVO: Avaliar o efeito da "laserterapia" na acuidade visual em portadores de retinopatia diabética avançada e sem queixas visuais. MÉTODOS: Desenvolveu-se estudo observacional descritivo em portadores de retinopatia diabética avançada e sem queixas visuais, submetidos a panfotocoagulação retiniana com laser de argônio. Foi realizado exame oftalmológico completo. Entre o 3° e o 5° meses do tratamento, foi repetido o exame inicial. Para comparação da acuidade visual, entre período pré e pós-tratamento, foi utilizado o teste não-paramétrico de Wilcoxon. RESULTADOS: A amostra foi constituída por 44 pacientes, totalizando 67 olhos, sendo que 37 (55,2 por cento) apresentavam retinopatia diabética proliferativa e 30 (44,8 por cento) não proliferativa grave ou muito grave. A acuidade visual pré-tratamento variou de 0,5 a 1,0 (média de 0,83 ± 0,17). Não houve alteração estatisticamente significante na acuidade visual (p= 0,057) pré e pós-tratamento no período estudado. CONCLUSÃO: Houve estabilidade visual pós-tratamento com a panfotocoagulação, o que enfatiza a necessidade de intervenções em fases mais precoces da retinopatia diabética para preservar a função visual.

PURPOSE: To evaluate the effect of laser treatment in the visual acuity caused by advanced diabetic retinopathy without visual complaints. METHODS: A descriptive observational study was developed in advanced diabetic retinopathy patients not presenting visual complaints. The patients were submitted to argon laser panretinal photocoagulation after ophthalmological examination as well as retinography and retinal angiofluoresceinography. The same initial exams were repeated between third and fifth months after the treatment. The non-parametric Wilcoxon test was employed for statistical evaluation between the visual acuities before and after the treatment. RESULTS: The sample involved 67 eyes of 44 patients. Of these 67 eyes, 37 (55.2 percent) presented proliferative diabetic retinopathy and 30 (44.8 percent) showed severe and severe non proliferative diabetic retinopathy. The visual acuity before the treatment ranged from 0.5 to 1.0 (mean 0.81 ± 0.16). There was no significant statistical difference between the visual acuity (p= 0.057) before and after the treatment during the follow-up period of five months. CONCLUSION: The visual stability after panretinal argon laser photocoagulation indicated the need of this treatment in early phases of diabetic retinopathy in order to preserve the visual function.

Interstitial laser coagulation in the management of lower urinary tract symptoms suggestive of bladder outlet obstruction from benign prostatic hyperplasia: long-term follow-up.

OBJECTIVE: To evaluate the long-term effects, including durability, of interstitial laser coagulation (ILC) in patients with symptomatic benign prostatic hyperplasia. PATIENTS AND METHODS: In all, 49 men (median age 68 years, range 52-80) were treated with ILC; 22 men were assessed for a median (range) of 54 (46-61) months. Information on the timing and type of re-treatment were collected for the remaining patients. RESULTS: The median (quartiles) International Prostate Symptom Score decreased from 22 (19-28) at baseline to 13 (5-21), a decrease of 41%. The peak urinary flow increased by 20% to 10.2 (8.7-12.9) mL/s. Twenty-two patients were re-treated (by any type) after ILC, giving a re-treatment rate of 50%. CONCLUSION: There were moderate effects on voiding variables and a high re-treatment rate during the long-term follow-up after ILC. It seems reasonable that the use of ILC is restricted to selected, high-risk patients.

Optimal parameters for the treatment of leg veins using Nd:YAG lasers at 1064 nm.

BACKGROUND: The treatment of large vessels such as leg veins is successfully performed in clinical practice using pulsed Nd:YAG lasers. However, it is still unclear how laser parameters such as wavelength, fluence and pulse duration influence vessel destruction in leg veins. OBJECTIVES: To elucidate the governing parameters in selective photothermolysis of large vessels. METHODS: A recently developed mathematical model for photothermolysis has been adapted for the treatment of leg veins. The model was used to analyse the effectiveness of the selective photothermolysis process in laser treatment of leg veins by Nd:YAG at 1064 nm. The efficiency of laser-induced vessel heating was defined as a ratio between the absorbed and delivered energy. RESULTS: The efficiency improved with increasing vessel diameter, in agreement with clinical findings in various studies. The pulse duration made a minor contribution for laser fluences of 100-400 J cm(-2), whereas the efficiency was better for a small spot. The use of moderate fluences of 100-200 J cm(-2) reduced excess dermis heating and pain. CONCLUSIONS: We provide reference parameters for optimal treatment of leg veins using Nd:YAG lasers at 1064 nm. Our model predicts a maximal efficiency of a range of fluences (100-200 J cm(-2)) and pulse durations (10-100 ms).