Infant ultrasound probe holder

Abstract

According to one aspect, the present disclosure relates to an ultrasound probe holding device (101) configured to be attached to an infant's head for transfontanel imaging, the ultrasound probe holding device comprising: a head pad (110) configured to contact the infant's head, having a central opening (115), and configured to receive an ultrasound probe; a pad squeezer (120) having a central opening (125) and configured to cooperate with the head pad to axially guide the head pad along a guidance axis (Δ) that is substantially perpendicular to a surface that contacts the infant's head; a device holder (150) configured to be attached to the infant's head and configured to apply a downward force to the pad squeezer along the guidance axis; and repulsion means configured to apply a repulsive force between the pad squeezer and the head pad when the device holder applies the downward force to the pad squeezer.

Description

[Technical Field]

[0001] The present disclosure relates to an ultrasound probe holder for an infant, and in particular to a device configured to be attached to the infant's head for fontanelle imaging. The present disclosure also relates to an ultrasound device including such an ultrasound probe holder, and to an ultrasound imaging system and method for infant brain imaging using such an ultrasound device. More particularly, the present disclosure relates to an ultrasound imaging system and method using such an ultrasound device for functional ultrasound brain imaging (fUS) of an infant. [Background technology]

[0002] The lack of effective and efficient imaging modalities to assess early brain function limits the clinical management of infants and our understanding of neurodevelopmental disorders. While functional magnetic resonance imaging (fMRI) is one of the best techniques available for brain imaging in adults, it is extremely complex to perform in newborns, making its use at the bedside for brain imaging in vulnerable infants particularly challenging. Clinically, near-infrared spectroscopy (NIRS) and electroencephalography (EEG), two techniques with low spatial resolution and limited activity measurements to the brain surface, are primarily used. Therefore, there is a need for the development of efficient and easy-to-use clinical neonatal functional brain imaging modalities and innovative portable methods that enable real-time monitoring of infant brain function.

[0003] Recently (see M. Tanter et al., “Ultrafast imaging in biomedical ultrasound,” IEEE Trans. Ultrason. Ferroelecr. Freq. Control 61, 102–119 (2014)), ultrafast ultrasound imaging has been introduced to achieve more than 10,000 ultrasound frames per second (compared to the typical 50 frames per second used in conventional ultrasound scanners). Ultrafast Doppler (UfD) imaging modes (see, e.g., E. Mace et al., “Functional ultrasound imaging of the brain: Theory and basic principles,” IEEE Trans. Ultrason. Ferroelecr. Freq. Control 60, 492–506 (2013)) improve the sensitivity of measuring blood flow in the human brain by up to 50 times. Unlike conventional Doppler techniques, which are limited to imaging large vessels, UfD imaging can map subtle hemodynamic changes in small cerebral vessels, i.e., vessels with a diameter of less than 200 μm.

[0004] Functional ultrasound imaging (fUSI) leverages these blood flow maps to image brain activity according to neurovascular coupling, which correlates regional neural activity with relative changes in cerebral blood volume (CBV). By providing real-time images of deep brain activity with high spatiotemporal resolution, fUSI enables imaging of brain activity during epileptogenesis, for example, as recorded with electroencephalography (EGG). fUSI also enables mapping of the brain's functional "connectivity," i.e., measuring brain activity when the brain is at rest.

[0005] Since fUSI investigates fluctuations in cerebral blood volume (CBV), its feasibility depends on observing the same imaging area for the entire imaging period, i.e., over a period of the order of one or ten minutes. This is particularly important in the case of mapping functional brain connectivity, where patients are examined at rest in the absence of external stimuli. In fact, the results are based on the correlation between CBV signals from different brain regions. Therefore, it is essential that the imaging area is stationary.

[0006] Initial preclinical experiments in small animals enabled this by fixing the probe to a 3D-printed mold attached to a motorized system, which positioned it within the plane of interest and maintained it in place throughout imaging. Rats and mice were immobilized in a stereotaxic apparatus. More recent experiments have developed metal, Plexiglas, or dental cement supports that are surgically implanted directly into the animal's skull, with the probe attached to the immobilization device using magnets or screws. In intraoperative proof-of-concept studies in humans, the patient's head was fixed in a stereotaxic apparatus and the probe was held by an articulated mechanical arm. In all of these configurations, the skull was either opened or surgically thinned.

[0007] All of these methods have in common that they are invasive and involve surgery, which obviously cannot be done in infants.

[0008] Additionally, while some functional imaging techniques, such as fMRI, require the infant to be restrained using straps, it is still desirable to minimize restraints on the infant. Therefore, techniques that aim to prevent head movement should be avoided whenever possible. This is particularly true for premature infants who must be placed in an incubator to complete their development. Additional equipment may be needed to monitor heart rate, respiratory rate, and blood oxygen saturation, as well as syringe pumps for feeding and administering appropriate medications.

[0009] Thus, due to the strong constraints of both the patient's vulnerability and the patient's surrounding environment, it is necessary to design an ultrasound probe holding device configured to be attached to the infant's head that can be used in an incubator alongside existing equipment, does not interfere with the infant's movements, and ensures stability of the ultrasound probe during the typical 10-minute imaging session.

[0010] Published utility model DE 94 05 271 U describes a device, or head mount, for receiving an ultrasound diagnostic probe in order to position the ultrasound diagnostic probe on the infant's skull and fix it with a holding device, on which the measuring probe is adjustably arranged in a probe bearing.

[0011] In a recent publication (see C. Demene et al., “Functional ultrasound imaging of brain activity in human newborns,” Sci. Transl. Med. 9, eaah6756 (2017)), we reported a flexible, noninvasive head mount customized for real-time functional ultrasound imaging of the neonatal brain. Specifically, we demonstrated the feasibility of fUSI by further combining ultrafast Doppler (UfD) imaging of cerebral microvasculature with simultaneous continuous video-electroencephalography (EEG) recording. To avoid motion artifacts typically associated with manual probe handling, a novel ultrasound probe holding device was designed. The ultrasound probe was inserted into a semirigid, biocompatible silicone head mount filled with ultrasound gel, allowing pivoting in a single plane. This device, along with the EEG electrodes, was held in place by soft, nonadhesive strips. This simple system demonstrated excellent robustness, and initial results of fUSI in neonates were obtained. Summary of the Invention [Problem to be solved by the invention]

[0012] However, prior art headmounts suffer from several drawbacks that limit their application. In particular, such headmounts can slip on the scalp and acoustic gel can leak from the headmount, potentially reducing the quality of the image and rendering concurrent EEG electrodes unusable. Furthermore, installation of the device is cumbersome and often impossible to perform alone. [Means for solving the problem]

[0013] The present disclosure relates to an ultrasound probe holder configured for attachment to an infant's head that is easy to attach and ensures exceptional stability of the ultrasound probe during imaging while minimizing pressure on the infant's head.

[0014] Hereinafter, "comprise" is a synonym (same meaning) of "include" and "contains," is inclusive and open, and does not exclude other elements not listed. Furthermore, in this disclosure, when referring to a numerical value, the words "about" and "substantially" are synonyms (same meaning) for a range consisting of 80% to 120%, preferably 90% to 110% of the numerical value. According to a first aspect, the present disclosure provides an ultrasound probe holding device configured for attachment to an infant's head for transfontanel imaging, the device comprising: a head pad configured to contact the infant's head, the head pad having a central opening and configured to receive an ultrasound probe; a pad squeezer having a central opening and configured to cooperate with the head pad to axially guide the head pad along a guidance axis substantially perpendicular to a surface that contacts the infant's head; a device holder configured to be attached to the infant's head and configured to apply a downward force to the pad squeezer along the guide axis; and a repulsive means configured to apply a repulsive force between the pad squeezer and the head pad when the device holder applies a downward force to the pad squeezer.

[0015] In this context, an infant is a young child, generally under 12 months of age, before the fontanelle has closed and therefore transfontanel imaging is possible. This includes premature and full-term newborns.

[0016] The applicant has shown that this unique arrangement of the ultrasound probe holding device according to the present disclosure allows for fine tuning of the pressure applied to the infant's head due to the repulsive force exerted between the pad squeezer and the head pad when the device holder exerts a downward force on the pad squeezer.

[0017] The ultrasound probe holder may be configured to be attached to the infant's head for transfontanel imaging through any fontanel of the infant's head, i.e., the anterior fontanel, the posterior fontanel, or the anterior fontanel.

[0018] According to one or more embodiments, the repulsive force has an amplitude that increases non-linearly with the distance between the head pad and the pad squeezer along the guiding axis, thereby further limiting pressure on the infant's head. In some embodiments, the repulsive force results in little or no contact between the pad squeezer and the head pad along the guiding axis during operation.

[0019] According to one or more embodiments, the amplitude of the repulsive force is such that the resulting pressure exerted by the head pad on the infant's head is between about 1 kPa and about 500 kPa (1 kPa = 1000 N / m 2 ), more preferably in the range of about 10 kPa to about 100 kPa. The pressure exerted on the infant's head must be great enough to provide sufficient traction, but not so great that the infant is unable to remain comfortable.

[0020] According to one or more embodiments, the axial guidance of the head pad along the guidance axis has lateral mechanical backlash, allowing relative movement between the pad squeezer and the head pad in a plane substantially perpendicular to the guidance axis. Such lateral backlash allows the baby to move their head slightly while maintaining static friction (stiction) between the head pad and their head due to the force applied by the device holder.

[0021] According to one or more embodiments, such lateral mechanical backlash is less than about 4 mm.

[0022] According to one or more embodiments, such lateral mechanical backlash is greater than about 0.5 mm.

[0023] According to one or more embodiments, the repulsion means includes repulsive magnets disposed on the head pad and the pad squeezer, respectively. The applicant has shown that the repulsive magnets are compatible with the lateral mechanical backlash of the axial guidance. Furthermore, the magnets allow the application of a repulsive force along the guidance axis whose amplitude increases nonlinearly with the distance between the head pad and the pad squeezer.

[0024] However, other resilience means are possible, such as resilience springs, cushioning materials such as foam, cushions with elastic walls and liquid filling, gas-filled cushions, etc.

[0025] According to one or more embodiments, the surface of the head pad configured to contact the infant's head is curved to conform to the shape of the head. This allows for easy attachment to the infant's head, distribution of pad pressure over a wider area of ​​the skin, and important traction. For example, the curved surface may have different curvatures in two orthogonal planes, typically the coronal / sagittal plane. Such curvatures may be selected to suit the infant's age and its specific anatomy, so that using the device at different ages simply involves selecting a compatible head pad from a predefined panel, while the other components remain unchanged.

[0026] According to one or more embodiments, the surface of the head pad configured to contact the infant's head is square or circular in cross section, where a square cross section prevents rotation of the head pad and / or probe about the steering axis for preferential imaging of coronal / sagittal planes, and a circular cross section allows imaging of any plane.

[0027] According to one or more embodiments, the device holder includes a harness of flexible material attached to the pad squeezer. Such flexible material may be fabric or plastic. In some embodiments, the harness may be removably attached to the pad squeezer, for example, attached to a hinged tab on the pad squeezer. In other embodiments, the harness and pad squeezer may be integrally formed.

[0028] According to one or more embodiments, the device holder is configured to mount electrodes for electroencephalography, thereby enabling electroencephalographic imaging in addition to ultrasound imaging.

[0029] According to one or more embodiments, the ultrasound probe holding device further comprises a probe holder configured to receive the ultrasound probe, said probe holder being fastened to the head pad.

[0030] According to one or more embodiments, the probe holder is removably fastened to the head pad. For example, the probe holder is removably fastened to the head pad using a magnet. When fastened to the head pad, the probe holder must be securely fastened to prevent movement.

[0031] According to one or more embodiments, the probe holder and head pad may be integrally formed.

[0032] According to one or more embodiments, when the probe holder is removably fastened to the head pad, the probe holder can be fastened to the head pad at at least two positions, and the at least two positions are obtained by rotating the probe holder about an axis parallel to the guidance axis. For example, the probe holder can be fastened to the head pad at two positions obtained by rotating the probe holder 90°. This allows imaging of different planes in the brain, such as coronal and sagittal planes, during operation.

[0033] According to one or more embodiments, the probe holder can be mounted to the head pad so as to be rotatable about an axis parallel to the guidance axis. According to a second aspect, the present disclosure provides an ultrasound device for infant fontanel imaging, comprising: an ultrasonic probe holding device according to a first aspect; and an ultrasound probe configured to be attached to the head pad, the ultrasound probe configured to emit ultrasound waves toward the infant's brain and receive backscattered ultrasound waves.

[0034] According to one or more embodiments, the ultrasound probe is rotatable about an axis of rotation that is substantially perpendicular to the steering axis.

[0035] According to one or more embodiments, the ultrasound probe is rotatable about an axis of rotation substantially parallel to the steering axis.

[0036] According to one or more embodiments, an ultrasound probe holding device includes a probe holder, and an ultrasound probe configured to be removably secured to the probe holder.

[0037] According to one or more embodiments, the ultrasound probe includes a matrix of transducers, said matrix of transducers being rotatable about an axis substantially perpendicular to the steering axis and / or rotatable about an axis substantially parallel to the steering axis.

[0038] According to a third aspect, the present disclosure provides an ultrasound imaging system for transfontanel imaging of an infant, comprising: an ultrasound device according to the second aspect; an electronic module configured to receive electrical signals transmitted by the ultrasound probe and to generate transduced signals; a computer configured to receive the converted signals from the electronic module and to calculate imaging data from the converted signals; The electrical signal is related to an ultrasound imaging system, where the electrical signal results from the detection of backscattered ultrasound waves. According to a fourth aspect, the present disclosure provides a method for ultrasound brain imaging of an infant using the ultrasound imaging system of the third aspect, comprising: Positioning the head pad on the baby's head; Filling the space formed by the opening in the head pad with ultrasound gel; fastening the ultrasound probe to the head pad so that the ultrasound probe is in ultrasonic contact with the infant's fontanelle; positioning the pad squeezer to enable axial guidance of the head pad along the guidance axis that is substantially perpendicular to a surface that contacts the infant's head; using the holding device to apply a downward force to the pad squeezer along the guide axis; The present invention relates to a method for transfontanel imaging, which includes emitting ultrasound waves with an ultrasound probe and detecting backscattered ultrasound waves.

[0039] In the method herein, the pressure on the baby's head is maintained in a controlled state thanks to the repulsive means of the ultrasound probe holding device, while the downward force applied to the pad squeezer along the guidance axis by the holding device creates static friction (i.e., stiction) between the baby's head and the head pad, limiting any movement of the head pad.

[0040] According to one or more embodiments, the method further includes adjusting the position of the head pad to adjust the field of view of the ultrasound probe. Such a step may be performed by acquiring an ultrasound image before applying a downward force to the pad squeezer with the holding device.

[0041] According to one or more embodiments, the method further includes rotating the ultrasound probe about an axis substantially perpendicular to the steering axis to image different oblique planes of the brain.

[0042] According to one or more embodiments, the method further includes rotating the ultrasound probe from at least one first position to a second position about an axis substantially parallel to the steering axis to image oblique coronal and sagittal sections of the brain.

[0043] According to one or more embodiments, the method further includes measuring an electroencephalogram using electroencephalography electrodes disposed on the holding device.

[0044] Other advantages and features of the invention will become apparent from the following description, illustrated by the drawings. [Brief explanation of the drawings]

[0045] [Figure 1A] FIG. 1A shows an exploded view of the right three-quarters of an ultrasound device according to one embodiment of the present disclosure. [Figure 1B] FIG. 1B shows an exploded view of the left three-quarters of an ultrasound device according to one embodiment of the present disclosure. [Figure 2A] FIG. 2A shows an exploded view of an embodiment of a head pad in an ultrasound device according to an embodiment of the present disclosure. [Figure 2B] FIG. 2B illustrates an exploded view of an embodiment of a head pad in an ultrasound device according to an embodiment of the present disclosure. [Figure 2C] FIG. 2C illustrates a top view of an embodiment of a head pad in an ultrasound device according to an embodiment of the present disclosure. [Figure 2D] FIG. 2D illustrates a side view of an embodiment of a head pad in an ultrasound device according to an embodiment of the present disclosure. [Figure 3] FIG. 3 illustrates an exploded view of an embodiment of a probe holder in an ultrasound device according to an embodiment of the present disclosure. [Figure 4A] FIG. 4A shows a diagram of an ultrasound device such as that shown in FIGS. 1A and 1B positioned on an infant's head in accordance with one embodiment of the present disclosure. [Figure 4B] FIG. 4B shows a diagram of an ultrasound device such as that shown in FIGS. 1A and 1B positioned on an infant's head in accordance with one embodiment of the present disclosure. [Figure 5] FIG. 5 illustrates an ultrasound imaging system for infant fontanel imaging that implements an ultrasound device according to the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0046] 1A and 1B show exploded views of the right and left three-quarters, respectively, of an ultrasound device 100 according to one embodiment of the present disclosure.

[0047] The example ultrasound device 100 of FIGS. 1A and 1B includes an ultrasound probe 140 configured to emit ultrasound waves toward the infant's brain and receive backscattered ultrasound waves, and an ultrasound probe holder 101 including a head pad 110 and a pad squeezer 120. The head pad 110 is configured to contact the infant's head and includes a central opening 115. The pad squeezer 120 includes a central opening 125 and is configured to cooperate with the head pad 110 to axially guide the head pad along a guidance axis (Δ). In operation, the guidance axis Δ is substantially perpendicular to a surface that contacts the infant's head. As described in more detail below, the ultrasound probe holder further includes a device holder (not shown in FIGS. 1A and 1B) configured to be attached to the infant's head and to apply a downward force to the pad squeezer along the guidance axis Δ. In the example of Figures 1A and 1B, the ultrasound probe holding device 101 further includes a probe holder 130 configured to receive an ultrasound probe 140, and the probe holder is configured to be fixed to the head pad 110.

[0048] According to some embodiments, the axial guidance of the head pad along the guidance axis has lateral mechanical backlash to allow relative movement between the pad squeezer and the head pad in a plane substantially perpendicular to the guidance axis. For example, the lateral mechanical backlash is less than about 4 mm and greater than about 0.5 mm. Such lateral backlash allows the infant to move their head slightly while maintaining a static friction force (stiction) between the head pad and their head due to the force applied by the device holder.

[0049] 2A and 2B are exploded views showing details of the head pad 110 and pad squeezer 120 of the ultrasonic probe holding device 101 shown in FIGS. 1A and 1B, respectively, and FIGS. 2C and 2D are top and side views thereof, respectively.

[0050] FIG. 3 is an exploded view of the probe holder 130 shown in FIGS. 1A and 1B.

[0051] Figures 4A and 4B show two different views of an ultrasound device 100 as shown in Figures 1A and 1B positioned on an infant's head 10 using a device holder 150. Figure 5 shows an ultrasound imaging system 500 for transfontanel imaging using an ultrasound device according to the present disclosure.

[0052] The ultrasound imaging system of Figure 5 includes an ultrasound device 510 according to the present disclosure having an ultrasound probe configured to emit ultrasound waves toward the brain of the infant 10 and to receive backscattered ultrasound waves. The ultrasound imaging system also includes an electronics module 520 configured to receive electrical signals transmitted by the ultrasound probe 140 and generate converted signals, and a computer 530 configured to receive the converted signals from the electronics module and calculate imaging data from the converted signals, the electrical signals resulting from detection of the backscattered ultrasound waves.

[0053] As will be described in more detail below, in the embodiments shown in FIGS. 1A, 1B, 2A-2D, and 3, the ultrasonic probe 140 is detachable from the probe holder 130, and the probe holder 130 is detachably fixed to the head pad 110. However, in some embodiments not shown, the probe holder 130 and the head pad 110 may form a single component. In other words, the ultrasonic probe 140 may be directly attached to the head pad 110 configured as a probe holder. Alternatively, the ultrasonic probe 140 may be fixed to the probe holder while being rotatable, as will be described in detail below.

[0054] 2A and 2B, the ultrasound probe holding device 101 further includes a repulsive means configured to apply a repulsive force between the pad squeezer 120 and the head pad 110 when the device holder 150 (not shown) applies a downward force to the pad squeezer 120. In this specification, a downward force is understood as a force applied along the guidance axis toward the baby's head.

[0055] For example, the repulsive means includes repulsive magnets 161 and 162 disposed on the head pad 110 and the pad squeezer 120, respectively. More specifically, in the example of FIGS. 2A and 2B, the head pad is provided with a plurality of repulsive magnets, four in this example. Each magnet 161 is disposed within the protrusion 113 so as to cooperate with a corresponding repulsive magnet 162 fitted in the groove 122 of the pad squeezer 120 in this example. For example, the poles of the magnet 162 of the pad squeezer 120 are oriented so as to repel the magnet 161 of the head pad 110, as indicated by the double arrows in FIGS. 2A and 2D. Thus, the magnets 161 and 162 function like compressed springs, tending to move the pad squeezer 120 away from the head pad 110. Therefore, the more the pad squeezer 120 is pressed against the head pad 110, the more the head pad 110 is pressed against the baby's skull.

[0056] The use of magnets as the repulsive means allows for the application of a repulsive force whose amplitude increases nonlinearly with the distance between the head pad and the pad squeezer along the guiding axis. Such a distance may be defined, for example, between the magnets 161 and 162. This further limits the pressure exerted on the infant's head. Practically, the magnets may be configured to prevent direct contact between the head pad and the pad squeezer along the guiding axis. This allows for complete control of the pressure exerted on the infant's head. This, combined with backlash between the pad squeezer and the head pad, allows for substantial movement of the pad squeezer 120 in a plane perpendicular to the guiding axis while maintaining the pressure exerted by the head pad 110 on the infant's head. This allows the head pad 110 and the probe holder 130 to remain in a constant position on the infant's head, regardless of movement of the pad squeezer 120 and / or the device holder 150, for example, due to the infant's head movement.

[0057] Of course, other known repulsive means such as a spring or a cushioning material may be used instead of the magnet.

[0058] As previously described, in the example of FIGS. 1A and 1B, the head pad 110 and the probe holder 130 are two separate components. This configuration facilitates installation, particularly the application of ultrasound gel during operation. The head pad 110 is configured to be attached to the infant's head and, during operation, to receive ultrasound gel within the space formed by the opening 115 and the skin of the head (not shown). As shown in FIGS. 2A and 2B, the head pad 110 may include a 3D-printed plastic support 112. A silicone pad 111 is attached to the support 112. The head pad 110 may be attached to the probe holder 130 with a magnet (not shown).

[0059] The shape of the head pad 110, as shown in FIG. 2A, is believed to be suitable for most infants. Because an infant's skull is oval rather than spherical, the surface of the head pad configured to contact the infant's head may be curved, and the curvature of said surface may be different in the sagittal and coronal directions. Thus, two radii of curvature data allow for the creation of as many shapes as necessary to accommodate all anatomical structures. For a given curvature, a counter-mold can be 3D printed that incorporates the desired shape of the head pad in a hollow.

[0060] In the embodiments shown in Figures 1A, 1B and 2A-2D, the different parts of the retainer are square in cross section. Obviously, this specification is not limited to a square shape, and the cross section of the head pad 110 and / or pad squeezer 120 may be of a different shape, for example, circular. All embodiments described herein are equally applicable to different shapes of head pad and / or pad squeezer.

[0061] As described in more detail below, a pad squeezer 120 is positioned over the head pad 110 to secure the head pad 110 to the baby's head. As shown, the pad squeezer 120 may include a frame 121 having articulating tabs 126 and 127 configured to rest on the forehead and back of the head, respectively, as shown in Figures 4A and 4B.

[0062] As shown in FIGS. 4A and 4B, the pad squeezer 120 is attached to the head via a device holder 150, such as a harness. The harness may comprise a flexible material, such as fabric or plastic. In the example shown in FIGS. 4A and 4B, the harness 150 includes straps that pass through hinged tabs 126, 127 of the pad squeezer 120 and are attached to the harness with, for example, a fastener strip, such as a Velcro® strip. However, in some embodiments, the harness and pad squeezer may be integrally formed. As previously explained, the use of repelling magnets, such as those described above, can apply the force required to hold the head pad 110 in place, regardless of the tension in the harness straps.

[0063] 3 shows in greater detail a non-limiting example of a probe holder 130 configured to hold an ultrasound probe 140. In this embodiment, the probe holder 130 is separate from the head pad 110.

[0064] In the example shown in FIG. 3 , the ultrasound probe 140 includes ultrasound transducers arranged in a matrix 141, e.g., a linear matrix, an electrical probe cable 145, a portion of which is shown in FIG. 3 , and straps 142, which are articulated along an axis Δ1 perpendicular to the guidance axis. The straps 142 include a mortise 143 configured to receive a tenon 135 of the probe holder's rotation blocker module 132 in this example. The probe holder 130 further includes a body 131. The rotation blocker module 132 is secured to the body 131 by sliding within two rails along the axis shown by the dotted lines in FIG. 3 and can be attracted to the probe holder's body by magnets. The solid arrows indicate the location of the magnets. The probe holder 130 may also include a locking crank 133 attached by a screw inserted into the tenon 135 and sliding within an arc-shaped rail. This crank 133 allows the screw to be tightened, thereby placing the tenon firmly on the body of the module and preventing rotation of the probe.

[0065] In the embodiment shown in Figure 3, the rotation blocker module 132 is designed to be easily replaced. A system of rails and magnets allows module replacement to be performed directly in the patient's room.

[0066] It is also possible to design a probe motorization system to replace manual probe rotation with electronically controlled rotation, for example using a servomotor. Such electronically controlled rotation can facilitate ultrasound tomography. In fact, by acquiring B-mode and Doppler images for each plane, it becomes possible to reconstruct a 3D volume from these acquired images.

[0067] Alternatively, an ultrasound probe including a rotatable matrix of transducers may be used to acquire planar B-mode or Doppler images.

[0068] The procedure for placing an ultrasound probe using an ultrasound probe holding device according to the present disclosure is greatly simplified.

[0069] First, a head pad 110, such as that shown in FIGS. 1A and 1B, may be placed on the infant's fontanel. While FIGS. 4A and 4B show transfontanel imaging through the anterior fontanel, transfontanel imaging may be performed through any fontanel of the infant. Next, the pad squeezer 120 and harness 150 (FIGS. 4A and 4B) are positioned, and the head pad 110 is placed on the infant's head 10. The head skin forms a sealed space with the head pad 110, which can be filled with ultrasound gel. Then, a probe holder 130, such as that shown in FIG. 3, may be secured to the head pad, for example, using a magnet attached to the inside of the head pad 110. In this way, the head pad 110 may be adjusted to accommodate the probe holder 130 with as little play as possible. Next, the ultrasound probe 140 can be tilted about axis Δ1 (FIG. 3) to image the desired plane. If necessary, the pad squeezer 120 and the straps of the holder 150 can all be manually adjusted slightly to properly center the probe in the fontanel.

[0070] In the example shown in Figures 1A and 1B, the probe holder 130 can be removed from the head pad 110, allowing for additional gel to be added as needed without repositioning the head pad 110. The curvature of the head pad also allows for a good seal around the gel reservoir, allowing, for example, simultaneous electroencephalography (EEG) to be performed, allowing electrodes to be placed as close as possible to the head pad without the risk of creating an electrical bridge between the electrodes through the gel. Furthermore, attaching the pad squeezer using a harness, such as that shown in Figures 4A and 4B, is very quick, and such harnesses are available in different sizes to optimally accommodate different infant morphologies. The total weight of the ultrasound device 100, as shown in Figures 4A and 4B, can be less than approximately 50 g.

[0071] The ultrasonic probe holding device is designed modularly, which can improve the fixation of the pad squeezer 120 without touching the head pad 110. Furthermore, the compactness of the ultrasonic device is improved.

[0072] The ultrasound probe holding device according to the present invention makes it possible to significantly improve the quality of ultrasound images, and enables recording for a long period of time up to 20 minutes.

[0073] The first study of infant sleep phases was conducted using an ultrasound imaging system, as shown in Figure 5, equipped with the ultrasound equipment described herein. A sequence formed by repeating basic blocks was performed. Each block consisted of ultrafast Doppler imaging consisting of three plane waves tilted at [-3°, 0°, 3°], emitted at a pulse repetition frequency of 1800 Hz and resulting in a frame rate of 600 Hz. These plane waves were emitted for 570 ms, allowing for the acquisition of 342 images at a depth of 30 mm. A 430 ms pause was then inserted to allow time for data transfer, beamforming, and hard disk storage. Thus, the total duration of this basic block was 1 s. The effective transmission time of 570 ms was selected to ensure at least one cardiac cycle could be registered in an infant with a heart rate of 120 beats per minute. This basic block was repeated for 20 minutes, ultimately resulting in a film of 1200 Power Doppler images at a rate of 1 Hz.

[0074] After the ultrasound probe holder is attached, electroencephalography (EEG) electrodes may be attached to the infant's scalp at open skin sites. These electrodes may also be part of the holder or may be placed simultaneously with securing the ultrasound probe holder to the infant's head. The EEG electrodes may then be connected to an EEG recorder for joint EEG-fUSI recording, which combines ultrafast Doppler (UfD) imaging of the cerebral microvasculature with simultaneous continuous video-electroencephalography (EEG) recording.

[0075] While the present invention has been described with respect to a limited number of embodiments, those skilled in the art, having the benefit of this disclosure, will appreciate that other embodiments may be devised which do not depart from the spirit of the invention as disclosed herein. Accordingly, the scope of the present invention should be limited only by the appended claims.

Claims

1. 1. An ultrasound probe holder (101) configured to be attached to an infant's head for transfontanel imaging, comprising: a head pad (110) configured to contact the head of the infant, having a central opening (115) and configured to receive an ultrasound probe; a pad squeezer (120) having a central opening (125) and configured to cooperate with the head pad to axially guide the head pad along a guidance axis (Δ) substantially perpendicular to a surface that contacts the baby's head; a device holder (150) configured to be attached to the head of the infant and configured to apply a downward force to the pad squeezer along the guidance axis; and a repulsive means configured to apply a repulsive force between the pad squeezer and the head pad when the device holder applies the downward force to the pad squeezer.

2. 2. The ultrasonic probe holding device according to claim 1, wherein the repulsive means includes repulsive magnets (161, 162) disposed on the head pad and the pad squeezer, respectively.

3. 3. The ultrasound probe holding device according to claim 1, wherein the surface of the head pad configured to come into contact with the baby's head is curved to fit the shape of the baby's head.

4. The ultrasound probe holding device of claim 3 , wherein the curved surface has different curvatures in two orthogonal planes.

5. 5. The ultrasonic probe holding device of claim 1, wherein the device holder includes a harness of flexible material attached to the pad squeezer.

6. 6. The ultrasound probe holding device according to claim 1, wherein the device holder is configured to mount electrodes for electroencephalography.

7. The ultrasonic probe holding device of any one of claims 1 to 6, further comprising a probe holder (130) configured to receive an ultrasonic probe (140), the probe holder being fastened to the head pad.

8. The ultrasonic probe holding device according to claim 7 , wherein the probe holder is removably fastened to the head pad.

9. 9. The ultrasonic probe holding device according to claim 8, wherein the probe holder can be fixed to the head pad at least at two locations.

10. An ultrasound device (100) for infant fontanel imaging, comprising: An ultrasonic probe holding device according to any one of claims 1 to 9; an ultrasound probe (140) configured to be attached to the head pad, the ultrasound probe configured to emit ultrasound waves toward the infant's brain and receive backscattered ultrasound waves.

11. The ultrasound device of claim 10 , wherein the ultrasound probe is rotatable about an axis of rotation substantially perpendicular to the guidance axis.

12. The ultrasound device according to claim 10 or 11, wherein the ultrasound probe is rotatable about a rotation axis substantially parallel to the guidance axis.

13. The ultrasonic probe holding device includes a probe holder (130), The ultrasound device of any one of claims 10 to 12, wherein the ultrasound probe (140) is configured to be removably fastened to the probe holder.

14. 1. An ultrasound imaging system for infant fontanel imaging, comprising: An ultrasound device (510) according to any one of claims 10 to 13, an electronic module (520) configured to receive electrical signals transmitted by the ultrasonic probe (140) and to generate transduced signals; a computer (530) configured to receive the converted signals from the electronic module and to calculate imaging data from the converted signals; An ultrasound imaging system wherein the electrical signal results from detection of the backscattered ultrasound waves.

15. 15. A method for ultrasound brain imaging of an infant using the ultrasound imaging system of claim 14, comprising: Positioning the head pad (110) on the head of the infant; Filling the space formed by the opening of the head pad with ultrasound gel; fastening the ultrasound probe (140) to the head pad so that the ultrasound probe is in ultrasonic contact with the infant's fontanelle; positioning the pad squeezer to enable axial guidance of the head pad along the guidance axis that is substantially perpendicular to a surface that contacts the infant's head; using the device holder (150) to apply a downward force to the pad squeezer along the guide axis; emitting ultrasound waves and detecting backscattered ultrasound waves using the ultrasound probe (140) for transfontanel imaging.

16. 16. The method of claim 15, further comprising rotating the ultrasound probe about an axis substantially perpendicular to the steering axis to image different oblique planes of the brain.

17. 17. The method of claim 15 or 16, further comprising rotating the ultrasound probe from at least one first position to a second position about an axis substantially parallel to the steering axis to image coronal and sagittal sections of the brain.

18. 18. The method of any one of claims 15 to 17, further comprising electroencephalography using electroencephalography electrodes disposed on the device holder.

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