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Trans-cranial focused ultrasound without hair shaving: feasibility study in an ex vivo cadaver model.

Eames MD, Hananel A, Snell JW, Kassell NF, Aubry JF - J Ther Ultrasound (2014)

Bottom Line: A human skull filled with tissue-mimicking phantom and covered with a wig made of human hair was sonicated using 220- and 710-kHz head transducers to evaluate the feasibility of acoustic energy transfer.Heating at the focal point was measured by MR proton resonance shift thermometry.Results showed that the hair had a negligible effect on focal spot thermal rise at 220 kHz and a 17% drop in temperature elevation when using 710 kHz.

View Article: PubMed Central - HTML - PubMed

Affiliation: Focused Ultrasound Foundation, Charlottesville, VA 22903, USA.

ABSTRACT
In preparing a patient for a trans-cranial magnetic resonance (MR)-guided focused ultrasound procedure, current practice is to shave the patient's head on treatment day. Here we present an initial attempt to evaluate the feasibility of trans-cranial focused ultrasound in an unshaved, ex vivo human head model. A human skull filled with tissue-mimicking phantom and covered with a wig made of human hair was sonicated using 220- and 710-kHz head transducers to evaluate the feasibility of acoustic energy transfer. Heating at the focal point was measured by MR proton resonance shift thermometry. Results showed that the hair had a negligible effect on focal spot thermal rise at 220 kHz and a 17% drop in temperature elevation when using 710 kHz.

No MeSH data available.


Related in: MedlinePlus

Skull with wig strapped to holder (left) and as seen on MR T2w sagittal image (right).
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Figure 3: Skull with wig strapped to holder (left) and as seen on MR T2w sagittal image (right).

Mentions: The hair is attached to the wig by the manufacturer with a dedicated cap. In order to investigate the relative influence of the hair and the cap, three setups were tested for each transducer: the bare skull (Figure 2), the same skull covered with a human hair wig (H-222, color 1, by Vivica Fox, Vivica A. Fox Hair Collection, Conshohocken, PA, USA; Figure 3), and the skull covered with only the cap part of the wig (used as baseline for the wig setup; Figure 4) after cutting the hair.


Trans-cranial focused ultrasound without hair shaving: feasibility study in an ex vivo cadaver model.

Eames MD, Hananel A, Snell JW, Kassell NF, Aubry JF - J Ther Ultrasound (2014)

Skull with wig strapped to holder (left) and as seen on MR T2w sagittal image (right).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4265964&req=5

Figure 3: Skull with wig strapped to holder (left) and as seen on MR T2w sagittal image (right).
Mentions: The hair is attached to the wig by the manufacturer with a dedicated cap. In order to investigate the relative influence of the hair and the cap, three setups were tested for each transducer: the bare skull (Figure 2), the same skull covered with a human hair wig (H-222, color 1, by Vivica Fox, Vivica A. Fox Hair Collection, Conshohocken, PA, USA; Figure 3), and the skull covered with only the cap part of the wig (used as baseline for the wig setup; Figure 4) after cutting the hair.

Bottom Line: A human skull filled with tissue-mimicking phantom and covered with a wig made of human hair was sonicated using 220- and 710-kHz head transducers to evaluate the feasibility of acoustic energy transfer.Heating at the focal point was measured by MR proton resonance shift thermometry.Results showed that the hair had a negligible effect on focal spot thermal rise at 220 kHz and a 17% drop in temperature elevation when using 710 kHz.

View Article: PubMed Central - HTML - PubMed

Affiliation: Focused Ultrasound Foundation, Charlottesville, VA 22903, USA.

ABSTRACT
In preparing a patient for a trans-cranial magnetic resonance (MR)-guided focused ultrasound procedure, current practice is to shave the patient's head on treatment day. Here we present an initial attempt to evaluate the feasibility of trans-cranial focused ultrasound in an unshaved, ex vivo human head model. A human skull filled with tissue-mimicking phantom and covered with a wig made of human hair was sonicated using 220- and 710-kHz head transducers to evaluate the feasibility of acoustic energy transfer. Heating at the focal point was measured by MR proton resonance shift thermometry. Results showed that the hair had a negligible effect on focal spot thermal rise at 220 kHz and a 17% drop in temperature elevation when using 710 kHz.

No MeSH data available.


Related in: MedlinePlus