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1.
J Clin Neurosci ; 111: 46-56, 2023 May.
Article in English | MEDLINE | ID: mdl-36948109

ABSTRACT

Spontaneous intracranial hypotension from spinal cerebrospinal fluid leak is a condition that often presents as orthostatic headaches. Diagnosis and localisation of spinal CSF leaks remain difficult despite multiple imaging modalities that can be used to aid identification. These include traditional CT myelography and MRI as well as newer techniques such as dynamic and digital subtraction myelography. Leaks can be classified into types and optimal localisation and management techniques vary by type of leak. Localisation of a leak can aid in targeting treatment such as an epidural blood patch if conservative measures fail. Where unsuccessful, repeated blood patches and novel techniques can be used to improve patient symptoms. Much of this condition is not well understood and evidence is lacking, with many avenues for potential research.


Subject(s)
Intracranial Hypotension , Humans , Intracranial Hypotension/diagnosis , Intracranial Hypotension/diagnostic imaging , Cerebrospinal Fluid Leak/diagnostic imaging , Cerebrospinal Fluid Leak/therapy , Myelography/methods , Tomography, X-Ray Computed/methods , Magnetic Resonance Imaging , Blood Patch, Epidural
2.
Sci Rep ; 9(1): 19901, 2019 12 27.
Article in English | MEDLINE | ID: mdl-31882742

ABSTRACT

Water quality is undergoing significant deterioration due to bacteria, pollutants and other harmful particles, damaging aquatic life and lowering the quality of drinking water. It is, therefore, important to be able to rapidly and accurately measure water quality in a cost-effective manner using e.g., a turbidimeter. Turbidimeters typically use different illumination angles to measure the scattering and transmittance of light through a sample and translate these readings into a measurement based on the standard nephelometric turbidity unit (NTU). Traditional turbidimeters have high sensitivity and specificity, but they are not field-portable and require electricity to operate in field settings. Here we present a field-portable and cost effective turbidimeter that is based on a smartphone. This mobile turbidimeter contains an opto-mechanical attachment coupled to the rear camera of the smartphone, which contains two white light-emitting-diodes to illuminate the water sample, optical fibers to transmit the light collected from the sample to the camera, an external lens for image formation, and diffusers for uniform illumination of the sample. Including the smartphone, this cost-effective device weighs only ~350 g. In our mobile turbidimeter design, we combined two illumination approaches: transmittance, in which the optical fibers were placed directly below the sample cuvette at 180° with respect to the light source, and nephelometry in which the optical fibers were placed on the sides of the sample cuvette at a 90° angle with respect to the to the light source. Images of the end facets of these fiber optic cables were captured using the smart phone and processed using a custom written image processing algorithm to automatically quantify the turbidity of each sample. Using transmittance and nephelometric readings, our mobile turbidimeter achieved accurate measurements over a large dynamic range, from 0.3 NTU to 2000 NTU. The accurate performance of our smartphone-based turbidimeter was also confirmed with various water samples collected in Los Angeles (USA), bacteria spiked water samples, as well as diesel fuel contaminated water samples. Having a detection limit of ~0.3 NTU, this cost-effective smartphone-based turbidimeter can be a useful analytical tool for screening of water quality in resource limited settings.


Subject(s)
Smartphone , Algorithms , Nephelometry and Turbidimetry , Water/analysis
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