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A forward-imaging needle-type OCT probe for image guided stereotactic procedures.

Liang CP, Wierwille J, Moreira T, Schwartzbauer G, Jafri MS, Tang CM, Chen Y - Opt Express (2011)

Bottom Line: The high signal-to-background characteristic of DOCT provides exceptional sensitivity in detecting and quantifying the blood flow within the sheep brain parenchyma in real time.The OCT/DOCT dual imaging also demonstrated its capability to differentiate the vessel type (artery/vein) on rat's femoral vessels.These findings demonstrate the suitability of OCT guidance during stereotactic procedures in the brain and its potential for reducing the risk of cerebral hemorrhage.

View Article: PubMed Central - PubMed

Affiliation: Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, USA.

ABSTRACT
A forward-imaging needle-type optical coherence tomography (OCT) probe with Doppler OCT (DOCT) capability has the potential to solve critical challenges in interventional procedures. A case in point is stereotactic neurosurgery where probes are advanced into the brain based on predetermined coordinates. Laceration of blood vessels in front of the advancing probe is an unavoidable complication with current methods. Moreover, cerebrospinal fluid (CSF) leakage during surgery can shift the brain rendering the predetermined coordinates unreliable. In order to address these challenges, we developed a forward-imaging OCT probe (740 μm O.D.) using a gradient-index (GRIN) rod lens that can provide real-time imaging feedback for avoiding at-risk vessels (8 frames/s with 1024 A-scans per frame for OCT/DOCT dual imaging) and guiding the instrument to specific targets with 12 μm axial resolution (100 frames/s with 160 A-scans per frame for OCT imaging only). The high signal-to-background characteristic of DOCT provides exceptional sensitivity in detecting and quantifying the blood flow within the sheep brain parenchyma in real time. The OCT/DOCT dual imaging also demonstrated its capability to differentiate the vessel type (artery/vein) on rat's femoral vessels. We also demonstrated in ex vivo human brain that the location of the tip of the OCT probe can be inferred from micro-anatomical landmarks in OCT images. These findings demonstrate the suitability of OCT guidance during stereotactic procedures in the brain and its potential for reducing the risk of cerebral hemorrhage.

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Related in: MedlinePlus

(A) Schematic of the handheld OCT system. FC: fiber coupler; PC: polarization controller; C: collimator, BD: balanced detector, MZI: Mach-Zehnder interferometer (frequency clocks), DAQ: data acquisition board, M: mirror, GSM: galvonometer scanning mirror, O: objective lens, AS: alignment stages, GL: GRIN lens needle. (B) GRIN needle. (C) GRIN needle placed beside a U.S. dime.
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g001: (A) Schematic of the handheld OCT system. FC: fiber coupler; PC: polarization controller; C: collimator, BD: balanced detector, MZI: Mach-Zehnder interferometer (frequency clocks), DAQ: data acquisition board, M: mirror, GSM: galvonometer scanning mirror, O: objective lens, AS: alignment stages, GL: GRIN lens needle. (B) GRIN needle. (C) GRIN needle placed beside a U.S. dime.

Mentions: Figure 1aFig. 1


A forward-imaging needle-type OCT probe for image guided stereotactic procedures.

Liang CP, Wierwille J, Moreira T, Schwartzbauer G, Jafri MS, Tang CM, Chen Y - Opt Express (2011)

(A) Schematic of the handheld OCT system. FC: fiber coupler; PC: polarization controller; C: collimator, BD: balanced detector, MZI: Mach-Zehnder interferometer (frequency clocks), DAQ: data acquisition board, M: mirror, GSM: galvonometer scanning mirror, O: objective lens, AS: alignment stages, GL: GRIN lens needle. (B) GRIN needle. (C) GRIN needle placed beside a U.S. dime.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3297117&req=5

g001: (A) Schematic of the handheld OCT system. FC: fiber coupler; PC: polarization controller; C: collimator, BD: balanced detector, MZI: Mach-Zehnder interferometer (frequency clocks), DAQ: data acquisition board, M: mirror, GSM: galvonometer scanning mirror, O: objective lens, AS: alignment stages, GL: GRIN lens needle. (B) GRIN needle. (C) GRIN needle placed beside a U.S. dime.
Mentions: Figure 1aFig. 1

Bottom Line: The high signal-to-background characteristic of DOCT provides exceptional sensitivity in detecting and quantifying the blood flow within the sheep brain parenchyma in real time.The OCT/DOCT dual imaging also demonstrated its capability to differentiate the vessel type (artery/vein) on rat's femoral vessels.These findings demonstrate the suitability of OCT guidance during stereotactic procedures in the brain and its potential for reducing the risk of cerebral hemorrhage.

View Article: PubMed Central - PubMed

Affiliation: Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, USA.

ABSTRACT
A forward-imaging needle-type optical coherence tomography (OCT) probe with Doppler OCT (DOCT) capability has the potential to solve critical challenges in interventional procedures. A case in point is stereotactic neurosurgery where probes are advanced into the brain based on predetermined coordinates. Laceration of blood vessels in front of the advancing probe is an unavoidable complication with current methods. Moreover, cerebrospinal fluid (CSF) leakage during surgery can shift the brain rendering the predetermined coordinates unreliable. In order to address these challenges, we developed a forward-imaging OCT probe (740 μm O.D.) using a gradient-index (GRIN) rod lens that can provide real-time imaging feedback for avoiding at-risk vessels (8 frames/s with 1024 A-scans per frame for OCT/DOCT dual imaging) and guiding the instrument to specific targets with 12 μm axial resolution (100 frames/s with 160 A-scans per frame for OCT imaging only). The high signal-to-background characteristic of DOCT provides exceptional sensitivity in detecting and quantifying the blood flow within the sheep brain parenchyma in real time. The OCT/DOCT dual imaging also demonstrated its capability to differentiate the vessel type (artery/vein) on rat's femoral vessels. We also demonstrated in ex vivo human brain that the location of the tip of the OCT probe can be inferred from micro-anatomical landmarks in OCT images. These findings demonstrate the suitability of OCT guidance during stereotactic procedures in the brain and its potential for reducing the risk of cerebral hemorrhage.

Show MeSH
Related in: MedlinePlus