Laser Speckle Contrast Imaging Research Articles

Comprehensive validation of a compact laser speckle contrast imaging system for vascular function assessment: from the laboratory to the clinic.

Proper organ functioning relies on adequate blood circulation; thus, monitoring blood flow is crucial for early disease diagnosis. Laser speckle contrast imaging (LSCI) is a noninvasive technique that is widely used for measuring superficial blood flow. In this study, we developed a portable LSCI system using an 805-nm near-infrared laser and a monochrome CMOS camera with a 10 × macro zoom lens. The system achieved a high-resolution imaging (1280 × 1024 pixels) with a working distance of 10 to 35 cm. The relative flow velocities were visualized via a spatial speckle contrast analysis algorithm with a 5 × 5 sliding window. In vitro experiments demonstrated the system's ability to image flow velocities in a fluid model, and a linear relationship was observed between the actual flow rate and the relative flow rate obtained by the system. The correlation coefficient (R2) exceeded 0.83 for volumetric flow rates of 0 to 0.2 ml/min when channel widths were greater than 1.2 mm, and R2 > 0.94 was obtained for channel widths exceeding 1.6 mm. Comparisons with laser Doppler flowmetry (LDF) revealed a strong positive correlation between the LSCI and LDF results. In vivo experiments captured postocclusive reactive hyperemic responses in rat hind limbs and human palms and feet. The main research contribution is the development of this compact and portable LSCI device, as well as the validation of its reliability and convenience in various scenarios and environments. Future applications of this technology include evaluating blood flow changes during skin injuries, such as abrasions, burns, and diabetic foot ulcers, to aid medical institutions in treatment optimization and to reduce treatment duration.

H2S-Eluting Hydrogels Promote In Vitro Angiogenesis and Augment In Vivo Ischemic Wound Revascularization

Ischemic wounds are frequently encountered in clinical practice and may be related to ischemia secondary to diabetes, peripheral artery disease and other chronic conditions. Angiogenesis is critical to the resolution of ischemia. Hydrogen sulfide (H2S) is now recognized as an important factor in this process. H2S donors NaHS and GYY4137 were incorporated into the photosensitive polymer hydrogel gelatin methacrylate and evaluated. Human umbilical vein endothelial cell (HUVEC) culture was used to quantify toxicity and angiogenesis. Sprague Dawley rats were subjected to ischemic myocutaneous flap wound creation with and without application of H2S-eluting hydrogels. Tissue perfusion during wound healing was quantified using laser speckle contrast imaging, and gene and protein expression for VEGF were evaluated. Vascular density was assessed by CD31 immunohistochemistry. Successful incorporation of sulfide compounds was confirmed by scanning electron microscopy with energy-dispersive X-ray analysis, and under physiologic conditions, detectable H2S was present for up to 14 days by high-performance liquid chromatography. HUVECs exposed to hydrogels did not demonstrate excess cytotoxicity or apoptosis. A two-fold increase in angiogenic tube formation was observed in HUVECs exposed to H2S-eluting hydrogels. Rat ischemic flap wounds demonstrated greater perfusion at 14 days, and there was greater vascularity of healed wounds compared to untreated animals. A nearly two-fold increase in VEGF mRNA and a four-fold increase in VEGF protein expression were present in wounds from treated animals. Local-regional administration of H2S represents a novel potential therapeutic strategy to promote angiogenesis and improve wound healing after tissue injury or as a result of ischemic disease.

Increased Levels of Circulating Methylglyoxal Have No Consequence for Cerebral Microvascular Integrity and Cognitive Function in Young Healthy Mice.

Diabetes and other age-related diseases are associated with an increased risk of cognitive impairment, but the underlying mechanisms remain poorly understood. Methylglyoxal (MGO), a by-product of glycolysis and a major precursor in the formation of advanced glycation end-products (AGEs), is increased in individuals with diabetes and other age-related diseases and is associated with microvascular dysfunction. We now investigated whether increased levels of circulating MGO can lead to cerebral microvascular dysfunction, blood-brain barrier (BBB) dysfunction, and cognitive impairment. Mice were supplemented or not with 50mM MGO in drinking water for 13weeks. Plasma and cortical MGO and MGO-derived AGEs were measured with UPLC-MS/MS. Peripheral and cerebral microvascular integrity and inflammation were investigated. Cerebral blood flow and neurovascular coupling were investigated with laser speckle contrast imaging, and cognitive tests were performed. We found a 2-fold increase in plasma MGO and an increase in MGO-derived AGEs in plasma and cortex. Increased plasma MGO did not lead to cerebral microvascular dysfunction, inflammation, or cognitive decline. This study shows that increased concentrations of plasma MGO are not associated with cerebral microvascular dysfunction and cognitive impairment in healthy mice. Future research should focus on the role of endogenously formed MGO in cognitive impairment.

Images in Vascular Medicine: Analysis of skin microvascular dysfunction in Harlequin syndrome using laser speckle contrast imaging.

Images in Vascular Medicine: Analysis of skin microvascular dysfunction in Harlequin syndrome using laser speckle contrast imaging.

Persistent Na + current couples spreading depolarization to seizures in Scn8a gain of function mice.

Spreading depolarization (SD) is a slowly propagating wave of massive cellular depolarization that transiently impairs the function of affected brain regions. While SD typically arises as an isolated hemispheric event, we previously reported that reducing M-type potassium current (I KM ) by ablation of Kcnq2 in forebrain excitatory neurons results in tightly coupled spontaneous bilateral seizure-SD complexes in the awake mouse cortex. Here we find that enhanced persistent Na + current due to gain-of-function (GOF) mutations in Scn8a (N1768D/+, hereafter D/+) produces a similar compound cortical excitability phenotype. Chronic DC-band EEG recording detected spontaneous bilateral seizure-SD complexes accompanied by seizures with a profound tonic component, which occurs predominantly during the light phase and were detected in the mutant mice across ages between P40-100. Laser speckle contrast imaging of cerebral blood flow dynamics resolved SD as bilateral wave of hypoperfusion and subsequent hour-lasting hypoperfusion in Scn8a D/+ cortex in awake head-restrained mice subjected to a subconvulsive PTZ. Subcortical recordings in freely moving mice revealed that approximately half of the spontaneous cortical seizure-SD complexes arose with concurrent SD-like depolarization in the thalamus and delayed depolarization in the striatum. In contrast, SD-like DC potential shifts were rarely detected in the hippocampus or upper pons. Consistent with the high spontaneous incidence in vivo , cortical slices from Scn8a D/+ mice showed a raised SD susceptibility, and pharmacological inhibition of persistent Na + current (I NaP ), which is enhanced in Scn8a D/+ neurons, inhibited SD generation in cortical slices ex vivo , indicating that I NaP contributes to SD susceptibility. Ex vivo Ca 2+ imaging studies using acute brain slices expressing genetic Ca 2+ sensor (Thy1-GCAMP6s) demonstrated that pharmacological activation of I KM suppressed Ca 2+ spikes and SD, whereas I KM inhibitor drastically increased the frequency of Ca 2+ spikes in the hippocampus of Scn8a D/+ mice, but not in WT, suggesting that I KM restrains the hyperexcitability resulting from Scn8a GOF mutation. Together, our study identifies a cortical SD phenotype in Scn8a GOF mice shared with the Kcnq2 - cKO model of developmental epileptic encephalopathy and reveals that an imbalance of non-inactivating inward and outward membrane currents bidirectionally modulates spatiotemporal SD susceptibility.

Statistical assessment of the inner shape of a channel based on laser speckle contrast imaging

In this work, we employed laser speckle contrast imaging coupled with the analysis of several statistical moments on the recorded images to recognize the shape of an object through the analysis of the pattern of a flow around it. We postulated that a flow through different geometries would generate a unique flow structure and thus the mathematical analysis of the differences can be utilized to detect and recognize various shape geometries. To this aim, the flow of scattered liquid that had passed through objects of different shapes was illuminated by a laser beam and the diffused speckle image was recorded by a camera. In the computer, the captured speckle image was first converted to a flow image and then mathematically analyzed to recognize the shape of the objects. Three out of the eight statistical metrics were found to be the best candidates for the recognition of shapes, thus proving our hypothesis.

A near-infrared triggered multi-functional indocyanine green nanocomposite with NO gas release function inducing improved photothermal therapy

The integration of photothermal and near-infrared (NIR) imaging capabilities of indocyanine green (ICG) small molecules has attracted considerable attention in tumor diagnosis and treatment. However, the abnormal upregulation of cellular heat shock proteins (HSPs) induced by photothermal therapy (PTT) enhances cellular heat resistance, thereby severely affecting the efficacy of PTT. In this study, to address the impact of HSPs on the efficacy of PTT while obtaining high-quality NIR fluorescence imaging in the NIR region, we designed a targeted peptide@ICG nanofluorescent probe encapsulated in liposomes. The introduced cRGD targeting peptide not only possesses tumor-targeting capabilities but also features LA as the last amino acid in the targeting peptide, which can generate nitric oxide (NO) under reactive oxygen species (ROS) triggering. It can happen under 808 nm single-light source NIR light, and the guanidine group in the peptide decomposes and combines with singlet oxygen molecules to generate NO gas molecules, thereby exerting an elevated photothermal effect by inhibiting the expression of HSP70. In addition, the nanoprobes enable deep imaging and treatment of glioma in situ and can be combined with a laser speckle contrast imaging (LSCI) system for multimodal imaging. This composite probe demonstrates synergistic tumor therapeutic effects of photodynamic therapy (PDT), PTT, and gas therapy, offering a promising strategy for cancer treatment.

Full-field amplitude speckle decorrelation angiography.

We propose a new simple and cost-effective optical imaging technique, full-field amplitude speckle decorrelation angiography (FASDA), capable of visualizing skin microvasculature with high resolution, and sensitive to small, superficial vessels with slow blood flow and larger, deeper vessels with faster blood flow. FASDA makes use of a laser source with limited temporal coherence, can be implemented with cameras with conventional frame rates, and does not require raster scanning. The proposed imaging technique is based on the simultaneous evaluation of two metrics: the blood flow index, a contrast-based metric used in laser speckle contrast imaging, and the adaptive speckle decorrelation index (ASDI), a new metric that we defined based on the second-order autocorrelation function that considers the limited speckle modulation that occurs in partially-coherent imaging. We demonstrate excellent delineation of small, superficial vessels with slow blood flow in skin nevi using ASDI and larger, deeper vessels with faster blood flow using BFI, providing a powerful new tool for the imaging of microvasculature with significantly lower hardware complexity and cost than other optical imaging techniques.

Microvascular effects of a mixed meal tolerance test: a model validation study

AbstractPurposeEndothelial dysfunction is a pathophysiological change preceding many cardiovascular events. Measuring improvements of endothelial function is challenging when function is already optimal, which may be remediated using a physiological challenge. This study aimed to determine whether imaging assessments can detect microvascular effects of a mixed meal tolerance test (MMTT).MethodsTwenty healthy volunteers (age ≥45 and ≤70 years) underwent two MMTTs at the beginning (Day 1) and end (Day 84) of a twelve‐week period. Imaging methods included laser speckle contrast imaging (LSCI) combined with post‐occlusive reactive hyperaemia (PORH) and local thermal hyperaemia (LTH) challenges, passive leg movement ultrasonography (PLM), and sidestream dark field microscopy (SDFM). Measurements were conducted pre‐MMTT and at 5 timepoints post‐MMTT for PLM and SDFM and 3 timepoints post‐MMTT for PORH and LTH.ResultsNo consistent effects of the MMTT were detected on LSCI LTH, PLM and SDFM endpoints. LSCI PORH maximum perfusion was significantly suppressed 46, 136, and 300 min post‐MMTT administration on Day 1, while residual perfusion decreased significantly 46 and 136 min post‐MMTT on Day 1. However, when repeated on Day 84, PORH endpoints were not significantly affected by the MMTT.ConclusionSDFM, PLM and LSCI LTH endpoints displayed high intra‐subject variability and did not detect consistent effects of MMTT. LSCI PORH endpoints displayed the lowest intra‐subject variability of all assessed endpoints and were affected by the MMTT on Day 1, but not on Day 84. Further standardization of methods or more robust challenges to affect vascular endpoints may be needed.

Assessment of hyperacute cerebral ischemia using laser speckle contrast imaging.

Accurate diagnosis of cerebral ischemia severity is crucial for clinical decision-making. Laser speckle contrast imaging based cerebral blood flow imaging can help assess the severity of cerebral ischemia by monitoring changes in blood flow. In this study, we simulated hyperacute ischemia in rats, isolating arterial and venous flow-related signals from cortical vasculature. Pearson correlation was used to examine the correlation between damaged vessels. Granger causality analysis was utilized to investigate causality correlation in ischemic vessels. Resting state analysis revealed a negative Pearson correlation between regional arteries and veins. Following cerebral ischemia induction, a positive artery-vein correlation emerged, which vanished after blood flow reperfusion. Granger causality analysis demonstrating enhanced causality coefficients for middle artery-vein pairs during occlusion, with a stronger left-right arterial effect than that of right-left, which persisted after reperfusion. These processing approaches amplify the understanding of cerebral ischemic images, promising potential future diagnostic advancements.

Reduced systemic microvascular function in patients with resistant hypertension and microalbuminuria: an observational study.

Resistant hypertension (RH) may be associated with microalbuminuria (MAU), a marker of cardiovascular risk and target organ damage, and both may be related to microvascular damage. Laser speckle contrast imaging (LSCI) is an innovative approach for noninvasively evaluating systemic microvascular endothelial function useful in the context of RH with or without MAU. Microalbuminuria was defined as a urine albumin-to-creatinine ratio between 30 and 300 mg/g. Microvascular reactivity was evaluated using LSCI to perform noninvasive measurements of cutaneous microvascular perfusion changes. Pharmacological (acetylcholine [ACh], or sodium nitroprusside [SNP]) and physiological (postocclusive reactive hyperemia [PORH]) stimuli were used to evaluate vasodilatory responses. Thirty-two patients with RH and a normal urine albumin-to-creatinine ratio (RH group) and 32 patients with RH and microalbuminuria (RH + MAU) were evaluated. Compared with patients without MAU, patients with RH + MAU showed reduced endothelial-dependent systemic microvascular reactivity, as demonstrated by an attenuation of microvascular vasodilation induced by PORH. On the other hand, ACh-induced vasodilation did not differ between groups. The results also revealed reduced endothelial-independent (SNP-induced) microvascular reactivity in hypertensive patients with MAU compared with patients without MAU. In this study, there was evidence of endothelial dysfunction associated with impaired microvascular smooth muscle function in patients with RH + MAU. This may suggest that patients with RH need more intensive therapeutic strategies for the control of blood pressure to avoid further vascular damage and the resulting consequences.The study was registered at ClinicalTrials.gov ( https://register.clinicaltrials.gov ) under protocol # NCT05464849, initial release 12/07/2022.

Jiawei Xionggui Decoction promotes meningeal lymphatic vessels clearance of β-amyloid by inhibiting arachidonic acid pathway

BackgroundAlzheimer's disease (AD) is an aging-associated form of dementia characterized by the pathological deposition of toxic misfolded proteins in the central nervous system (CNS), which is closely related to the clearance impairment of meningeal lymphatic vessels (mLVs). Thus, enhancement dural meningeal lymphatic drainage to remove amyloid-β (Aβ) is usually considered as a potential therapeutic target for AD. PurposeThis study aimed to investigate the mechanisms of Jiawei Xionggui Decoction (JWXG) to attenuate cognitive dificits in APP/PS1 mice with impaired meningeal lymphatic drainage. MethodsLigation of deep cervical lymph nodes (dcLNs) was performed to establish the mice model of the impaired meningeal lymphatic drainage in APP/PS1 mice. Cognitve behaviors and pathological morphology of mice were assessed. Cerebral blood flow (CBF) of mice was determined using Laser speckle contrast imaging analysis. Serum non-targeted metabolomics analysis was applied to decipher the mechanisms of JWXG in rescuing the impairment of mLVs, and C8-D1A cells were employed to validate in vitro. ResultsDisruption of mLVs in APP/PS1 mice deteriorated cognitive dysfunction, accelerated Aβ burden and glia activation, accompanied by more severe neuropathological damage, CBF reduction and neuroinflammation exacerbation. Serum non-targeted metabolomics analysis indicates the increase of arachidonic acid (AA) metabolic pathway was the key contributor to the neuropathological exacerbation of dcLNs ligation APP/PS1 mice. Interestingly, clinically equivalent dose of JWXG was sufficient to restore mLVs drainage and rescue cognitive performance by inhibiting neuroinflammation depended by AA metabolic pathway in dcLNs ligation APP/PS1 mice. ConclusionOur findings establish a novel mechanism that rescue mLVs by inhibiting AA metabolic pathway to clear brain Aβ, and support JWXG as a feasible treatment strategy for AD by suppressing AA metabolic pathway to improve mLVs drainage efficiency.

Peripheral Inflammation is accompanied by Cerebral Hypoperfusion in Mice.

Chronic pain is a disabling condition that is accompanied by neuropsychiatric comorbidities such as anxiety, depression, and cognitive decline. While the peripheral alterations are well-studied, we lack an understanding of how these peripheral changes can result in long-lasting brain alterations and the ensuing behavioral phenotypes. This study aims to quantify changes in cerebral blood perfusion using laser speckle contrast imaging (LSCI) in the murine Complete Freund's adjuvant (CFA) model of unilateral peripheral inflammation. Twenty female and 24 male adult C57BL/6 mice were randomly assigned to control (0.05ml saline) or 1 of 3 experimental groups receiving CFA (0.01ml, 0.05ml, and 0.1ml) on the right hindpaw. Three days after the intraplantar injections, animals were assessed for signs of pain (von Frey), working memory (y-maze), and anxiety (zero maze and open field), and subjected to craniotomy and in vivo LSCI of the parietal-temporal lobes. Unilateral administration of CFA resulted in signs of local inflammation, decreased mechanical thresholds on the affected hindpaw, signs of anxiety in the zero maze, as well as cerebral hypoperfusion in dose-dependent manner. To our knowledge, this is the first study using laser speckle contrast imaging to examine the effects of CFA-induced peripheral inflammation on cerebral blood perfusion. It serves as a first step in delineating the path by which insult to peripheral tissues can cause long-lasting brain plasticity via vascular mechanisms.

Brucea javanica Seed Oil Emulsion and Shengmai Injections Improve Peripheral Microcirculation in Treatment of Gastric Cancer.

To explore and verify the effect and potential mechanism of Brucea javanica Seed Oil Emulsion Injection (YDZI) and Shengmai Injection (SMI) on peripheral microcirculation dysfunction in treatment of gastric cancer (GC). The potential mechanisms of YDZI and SMI were explored through network pharmacology and verified by cellular and clinical experiments. Human microvascular endothelial cells (HMECs) were cultured for quantitative real-time polymerase chain reaction, Western blot analysis, and human umbilical vein endothelial cells (HUVECs) were cultured for tube formation assay. Twenty healthy volunteers and 97 patients with GC were enrolled. Patients were divided into surgical resection, surgical resection with chemotherapy, and surgical resection with chemotherapy combining YDZI and SMI groups. Forearm skin blood perfusion was measured and recorded by laser speckle contrast imaging coupled with post-occlusive reactive hyperemia. Cutaneous vascular conductance and microvascular reactivity parameters were calculated and compared across the groups. After network pharmacology analysis, 4 ingredients, 82 active compounds, and 92 related genes in YDZI and SMI were screened out. β-Sitosterol, an active ingredient and intersection compound of YDZI and SMI, upregulated the expression of vascular endothelial growth factor A (VEGFA) and prostaglandin-endoperoxide synthase 2 (PTGS2, P<0.01), downregulated the expression of caspase 9 (CASP9) and estrogen receptor 1 (ESR1, P<0.01) in HMECs under oxaliplatin stimulation, and promoted tube formation through VEGFA. Chemotherapy significantly impaired the microvascular reactivity in GC patients, whereas YDZI and SMI ameliorated this injury (P<0.05 or P<0.01). YDZI and SMI ameliorated peripheral microvascular reactivity in GC patients. β-Sitosterol may improve peripheral microcirculation by regulating VEGFA, PTGS2, ESR1, and CASP9.

Exploring the translational impact of type 1 diabetes on cerebral neurovascular function through ECoG-LSCI.

Type 1 diabetes mellitus (T1DM) can result in complications such as retinopathy, nephropathy, and peripheral neuropathy, which can lead to brain dysfunction. In this study, we investigated the effects of T1DM on cerebral neurovascular function in mice. Streptozotocin (STZ) is known to induce T1DM in animals; thus, we used an STZ-induced diabetes model to evaluate the effects of hyperglycemia on brain morphology and neurovascular tissue. Neurovascular coupling is the connection between neuronal activity and cerebral blood flow that maintains brain function. The ECoG-LSCI technique combines electrocorticography (ECoG) and laser speckle contrast imaging (LSCI) to detect cortical spreading depression (CSD) as a marker of neurovascular coupling and measure corresponding neurovascular function. Our results suggested that in the STZ group, hyperglycemia affected excitatory neurotransmission and metabolism, leading to reductions in intercellular signaling, somatosensory evoked potential (SSEP) amplitudes, and CSD transmission rates. Western blot data further revealed that brain-derived neurotrophic factor (BDNF) and neuronal nuclear antigen levels were reduced in the STZ group. Abnormalities in glucose metabolism in the brain and increased phosphorylation of AKT and GSK3 are hypothesized to be responsible for these decreases. Overall, this study highlights the importance of glucose metabolism in normal brain physiology and demonstrates that hyperglycemia disrupts neurovascular coupling and affects cerebral neurovascular function and that the degree of CSD is positively correlated with the extent of brain tissue damage. Further research is essential to gain a complete understanding of the related mechanisms and the implications of these findings.

Cervical Clamping Does Affect Ovine Uterine Perfusion: A Laser Speckle Contrast Imaging Study

Cervical Clamping Does Affect Ovine Uterine Perfusion: A Laser Speckle Contrast Imaging Study

Automated non-invasive laser speckle imaging of the chick heart rate and extraembryonic blood vessels and their response to nifedipine and amlodipine drugs.

Non-invasive Laser Speckle Contrast Imaging (LSCI) of the chick chorioallantoic membrane (CAM) in whole incubated eggsSimultaneous recording images of the CAM, dynamics of blood flow, and heart rateLive view mode to identify size, heart position, and location of the embryo in the eggAutomated system for data acquisition and analysisLongitudinal quantification of the impact of a calcium channel antagonists, nifedipidine and amlodipine on the embryonic heart rate, CAM's blood flow, size and number of vessels.

Detailed measurements of the four extraocular rectus muscles’ contribution to the perfusion of the anterior segment of the eye

Background/aimsAnterior segment ischaemia (ASI) is a rare but serious complication of strabismus surgery, which may be caused by damage to the anterior ciliary arteries that run along the rectus muscles....

Metabolomic profiling integrated with molecular exploring delineates the action of Ligusticum chuanxiong hort. on migraine

IntroductionLigusticum chuanxiong hort. (Chuanxiong, CX) is a well-known traditional edible-medicinal herb, especially in brain diseases. However, there is a lack of studies focusing on the action of CX in metabolites of migraine. Hypothesis/purposeTo investigate the action of the aqueous extract of CX (LCH) on nitroglycerin (NTG)-induced migraine. MethodsThe effects and mechanisms of LCH on migraine were evaluated in NTG-induced mice and rats. Laser speckle contrast imaging was performed to detect the cerebral blood flow. Metabolomic analysis in serum and mass spectrometry imaging in brain tissue from NTG-induced rats were conducted to explore the metabolites. The techniques including RT-qPCR, immunohistochemistry, and immunofluorescence were employed to estimate the molecular changes. ResultsTotally, 1480 metabolites were identified, among which, 50 and 49 differential metabolites were identified by t-test, fold change, and VIP score for NTG vs. CON and LCH+NTG vs. NTG, respectively. Next, 13 common real difference metabolites were revealed by comparative analysis, and KEGG annotation and enrichment analysis showed that the glutathione (GSH) metabolism pathway played important roles in migraine, whereas the glutamate could be metabolized to γ-glu-cys and converted to GSH. Molecular exploring further confirmed that LCH treatment increased the expression of essential components of GSH synthetase, such as GCLC and GCLM, and elevated the expression levels of Nrf-2 and its downstream targets including HO1 and NQO1. Moreover, the mass spectrometry imaging results found that LCH treatment promoted the synthesis of GSH and the spatial distribution of glucose as well as ATP metabolites to normal levels. ConclusionTo sum up, the present study firstly reveals that LCH plays a therapeutic role for migraine through glucose-glutamate-Nrf-2 axis, which might represent a promising approach in the development of advanced therapeutic strategies for migraine, and the LCH may be an effective drug or dietary supplement for relieving headache.

Role of pterygopalatine ganglion in regulating isoflurane-induced cerebral hyper-perfusion.

Cerebral perfusion is functionally regulated by neural mechanisms in addition to the systemic hemodynamic variation, vascular reactivity and cerebral metabolism. Although anesthesia is generally esteemed to suppress the overall brain neural activity and metabolism, a few inhalation anesthetics, such as isoflurane, can increase cerebral perfusion, thus heightening the risks of higher intracranial pressure, bleeding, and brain edema during surgery. With the aid of laser speckle contrast imaging, we observed a transient yet limited effect of cerebral perfusion enhancement in mice from awake to anesthetized conditions with different concentration of isoflurane. Retrograde and antegrade tracing revealed a higher proportion of parasympathetic control more than sympathetic innervation for the blood vessels. Surprisingly, isoflurane directly activated pterygopalatine ganglion (PPG) explants and induced FOS expression in the cholinergic neurons. Chemogenetic activation of cholinergic PPG neurons reduced isoflurane-related cerebral perfusion. On the contrary, ablation of the cholinergic PPG neurons resulted in further enhancement of cerebral perfusion induced by isoflurane. While blocking muscarinic cholinergic receptors resulted in the overall reduction upon isoflurane stimulation, the blockage of nicotinic cholinergic receptors enhanced the isoflurane-induced cerebral perfusion only when PPG neurons exist. Collectively, these results suggest that PPG play important roles in regulating cerebral perfusion under isoflurane inhalation.