Lower energy and pulse stacking. A safer alternative for skin tightening using fractional CO2 laser

PURPOSE : To evaluate the effect of different energies and stacking in skin shrinkage. METHODS : Three decreasing settings of a fractional CO2 laser were applied to the abdomen of Twenty five Wistar rats divided into three groups. Group I (n=5) was histologically evaluated for microthermal zones dimensions. Groups II and III (n=10 each) were macroscopic evaluated with freeware ImageJ for area contraction immediately and after 30 and 60 days. RESULTS : No statistical significance was found within microthermal zone histological dimensions (Group I) in all settings studied. (Ablation depth: 76.90 to 97.18µm; Coagulation depth: 186.01 to 219.84 µm). In Group II, macroscopic evaluation showed that all settings cause significant immediate skin contraction. The highest setting cause significant more intense tightening effect initially, contracting skin area from 258.65 to 179.09 mm2. The same pattern was observed in Group III. At 30 and 60 days, the lowest setting significantly sustained contraction. CONCLUSION : Lower fractional CO2 laser energies associated to pulse stacking could cause consistent and long lasting tissue contraction in rats.

Caracterización de la Retinopatía de la prematuridad entre el período de 2008 y 2014 en Barranquilla - Colombia / Characterization of Retinopathy of prematurity between 2008 and 2014 in Barranquilla - Colombia

Objetivo: establecer la prevalencia, factores de riesgo y resultados anatómicos asociados a la Retinopatía de la Prematuridad en neonatos con edad gestacional menor o igual a 32 semanas y peso menor o igual de 1.750 g en 14 unidades de cuidados intensivos de la ciudad de Barranquilla ­ Colombia entre el periodo del 2008 al 2014. Diseño: estudio descriptivo transversal con análisis de casos y controles. Materiales y Métodos: datos recolectados de fuente secundaria. Criterios de inclusión: recién nacidos pretérmino de ≤32 semanas de Edad Gestacional y/o Peso al Nacer ≤ 1750 g y pacientes >32 semanas y peso al nacer >1750 g que por factores de riesgo sistémicos su neonatólogo solicitó el examen. Se excluyeron pacientes con historias clínicas incompletas. Las variables estudiadas fueron : edad gestacional, peso al nacer, sexo, edad cronológica, sepsis, oxigeno, enfermedad de membrana hialina, cirugías perinatales, hemorragias intraventriculares, transfusiones, embarazo gemelar, presencia de ROP, distribución de ROP por estadío, zonas y tipo, distribución según el tratamiento implementado y la relación de este con el peso y la edad gestacional. Se realizó tratamiento con Fotocoagulación Láser a pacientes con ROP Pre-umbral Tipo 1 y Tratamiento Combinado de Láser con Bevacizumab Intravítreo a los pacientes con enfermedad Umbral. Resultados: Se estudiaron 1038 ojos y de estos presentaron ROP Umbral 80 ojos con una prevalencia del 7.7% y ROP Preumbral Tipo 1 88 ojos con una prevalencia del 8.7% los cuales requirieron tratamiento. La mayor proporción de pacientes con ROP por edad gestacional estuvo en el rango de 27 a 28 semanas con el 37.8%, seguido del rango de 29 a 30 semanas con el 23.6% y luego el rango de 31-32 semanas con el 18.9%. De los pacientes con ROP, el 32.9% tenían entre 751 ­ 1000 g, seguidos del grupo de 1001 - 1250 g con el 30.7%. Se encontró una relación estadísticamente significativa con bajo peso al nacer, edad gestacional entre 26 y 28 semanas, oxigenoterapia y enfermedad de membrana hialina. El 96.6% de los pacientes con ROP Pre-Umbral Tipo 1 que fueron tratados con láser presentó involución de la ROP y sólo el 3.4% requirió Terapia de Rescate a los 15 días por actividad de su retinopatía. Ningún paciente en este grupo evolucionó a Estadío 4 y/o 5. El 93.7% de los pacientes con ROP Umbral que recibieron tratamiento combinado con Láser y Terapia Intravítrea con bevacizumab (0.65 mg/0.05 cc) presentó involución de la ROP; 73% requirieron una sola dosis de bevacizumab mientras que el 26.6% requirió 2 dosis. 4 ojos progresaron a estadío 4a. De los grupos tratados ningún caso evolucionó a Estadío 5. Conclusiones: la prevalencia de ROP Umbral fue de 7.7% y de ROP Pre-umbral Tipo 1 fue de 8.7% y el tratamiento oportuno fue eficaz en evitar la progresión de la retinopatía. Se resalta la necesidad de manejo multidisciplinario de la retinopatía del prematuro, el cual inicia con los programas de prevención primaria y prevención secundaria. Los factores de riesgo asociados a la ROP en nuestro medio son Edad gestacional < 28 semanas, peso al nacer < 1250g, oxigenoterapia y EMH.

Objective: to describe the prevalence, risk factors and anatomic results associated with retinopathy of prematurity (ROP) in infants with gestational age < 32 weeks and ≤1,750g in 14 NICUs in Barranquilla ­ Colombia between 2008 and 2014. Design: cross sectional study with casecontrol analysis. Materials and Methods: data collected from secondary sources. Inclusion criteria: infants ≤32 weeks and / or ≤ 1750 g and patients > 32 weeks and weight >1750 g if screening by risk factors was recommended by neonatologist. Patients with incomplete medical records were excluded. The variables studied were: gestational age, birth weight, gender, chronological age, twin pregnancy, sepsis, oxygen, respiratory distress, perinatal surgeries, intraventricular hemorrhage, blood transfusion, presence of ROP, distribution of ROP by stage, areas and type, distribution according to the treatment and the relationship with weight and gestational age. Laser photocoagulation treatment in patients with Pre-Threshold ROP Type 1 and a Combined Treatment of Laser and Intravitreal Bevacizumab in patients with Threshold Disease was performed. Results: we studied 1038 eyes. Threshold ROP was diagnosed in 80 eyes with a prevalence of 7.7% and Pre-Th reshold ROP Type 1 was diagnosed in 88 eyes with a prevalence of 8.7%. In both groups treatment were required. The largest proportion of patients with ROP by gestational age were ranged from 27 to 28 weeks group with 37. 8%, followed by the range of 29-30 weeks group in 23.6% and the 31-32 weeks group had 18.9%. 32.9% of patients with ROP were in 751 ­ 1000 g group, followed by 1001-1250 g group with 30.7%. A statistically significant diff erence was found between low birth weight, gestational age between 26 and 28 weeks, oxygen and respiratory distress. 96.6% of ROP Pre-Threshold Type 1 infants treated with Laser had a completed resolution of ROP. 3.4% required a Rescue Th erapy 15 days after initial treatment which consist of Intravitreal Inyection of Bevacizumab (0.65 mg/0.05 cc) and a second Laser treatment. Involution of ROP was achieved in all infants from this group. 93.7% of ROP Threshold infants treated with a combined treatment of Laser and Intravitreal Bevacizumab Inyection (0.65 mg / 0.05 cc). 73% of infants required a single dose of intravitreal bevacizumbab and 26.6% required 2 doses. 4 eyes progressed to Stage 4a. Conclusions: the prevalence of Threshold ROP was 7.7% and Pre-Threshold ROP Type 1 was 8.7%. A multidisciplinary management of ROP with programs of primary and secondary prevention is necessary to be implemented. Risk factors associated with ROP in our study are gestational age <28 weeks, birth weight <1250 g, oxygen and respiratory distress.

Experience with the Pascal® photocoagulator: An analysis of over 1200 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 × time. Most frequently used patterns were single spot (89% of cases) in FP, 5 × 5 box (72%) in PRP, and 2 × 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.

ND - YAG laser treatment of haemangiomas in children

Management of 30 cases of mixed hemangiomas in the head and neck with Nd-YAG laser was presented. All cases were investigated using computerized axial tomography and CT scanning for the detection of any deep vascular connections. Nd-YAG 1064 nm was applied with a power ranging from 12 to 16 W and exposure duration from l to 2 sec. The follow-up period for any recurrence or incomplete healing was done. Although the treatment with Nd-YAG laser resulted in scarring, this was accepted by the patients as it was less risky and much easier than other surgical procedures. Technique, post treatment care and follow up results were presented in details