RESUMO
OBJECTIVE: The aim of this study was to investigate the potential confounding effects of four different types of ambient lighting on the results of Laser Doppler Imaging (LDI) of a standardized cutaneous injury model. METHODS: After applying a mechanical stimulus to the anterior forearm of a healthy volunteer and inducing a wheal and arteriolar flare (the Triple response), we used a Laser Doppler Line Scanner (LDLS) to image the forearm under four different types of ambient lighting: light-emitting-diode (LED), compact fluorescent lighting (CFL), halogen, daylight, and darkness as a control. A spectrometer was used to measure the intensity of light energy at 785 nm, the wavelength used by the scanner for measurement under each type of ambient lighting. RESULTS: Neither the LED nor CFL bulbs emitted detectable light energy at a wavelength of 785 nm. The color-based representation of arbitrary perfusion unit (APU) values of the Triple response measured by the scanner was similar between darkness, LED, and CFL light. Daylight emitted 2 mW at 785 nm, with a slight variation tending more towards lower APU values compared to darkness. Halogen lighting emitted 6 mW of light energy at 785 nm rendering the color-based representation impossible to interpret. CONCLUSIONS: Halogen lighting and daylight have the potential to confound results of LDI of cutaneous injuries whereas LED and CFL lighting did not. Any potential sources of daylight should be reduced and halogen lighting completely covered or turned off prior to wound imaging.
RESUMO
OBJECT: The aim of this study was to quantify the financial costs of surgical intervention in patients with newly diagnosed hydrocephalus and patients with treatment failure or complications of previously treated hydrocephalus between 2007 and 2009 at the Children's Hospital at Westmead in Sydney, Australia. METHODS: This was a retrospective study of patients who underwent shunt insertion, shunt revision, treatment of an infected shunt, and endoscopic third ventriculostomy (ETV) between 2007 and 2009. Actual hospital costs associated with each inpatient stay were obtained from the accounting office of Children's Hospital at Westmead. Patients with hydrocephalus secondary to trauma, malignancy, or other complex conditions (except myelomeningocele) were excluded. RESULTS: Hydrocephalus-related procedures comprised approximately one-third of neurosurgical procedures performed each year. From 2007 to 2009, there were 192 admissions during which 300 procedures were performed for 162 patients. The total cost was $4.78 million (Australian) with an average cost of $1.59 million per year. The cost per admission for shunt insertion and ETV were similar ($13,905 vs $14,128, respectively). The average cost per admission for shunt revision was $9,753. However, shunt infection was associated with 40% of total costs, averaging $83,649 per admission. Management of patients with myelomeningocele undergoing insertion of shunt procedures in the same admission accounted for an average cost of $50,186. CONCLUSIONS: Hydrocephalus is a chronic condition that imposes a significant and growing economic burden upon the Australian hospital system. Seventy-five percent of hydrocephalus-related hospital expenditure is used to surgically treat patients for complications or failure of previously treated hydrocephalus. Further research into the economic impact of pediatric hydrocephalus on the Australian health care system and concerted research efforts in the area of effective long-term surgical treatment and complication minimization are essential.
