The current invention relates to a light emitting, preferably manually guided, tip light laryngoscope, which light source is built at the tip of the laryngoscope blade to visualize and examine the laryngeal inlet of a patient as a means to assist clini cians inserting the endotracheal tube as it passes through the pharynx towards the bifurcation.

Laryngoscopes are well known to the state of the art as numerous guiding meth ods, styles, variations and techniques for conventional and digital laryngeal intu bation have been developed over time.

A laryngoscope is a device which is used by clinicians during tracheal intubation.

It assists with intubation by allowing clinicians to visualize the path of the endotra cheal tube as it passes the pharynx towards the glottic entrance into the trachea. The pathway can become critical when patients are difficult to intubate, especially in cases of defense reactions due to discomfort, anatomical abnormalities or inju ries. This applies in specific when intubation is carried out by less experienced cli nicians or such personnel in training.

In most recent developments, a laryngoscope - comprising of a handle and a blade - therefore often includes auxiliary guided means (US 2011/0178369 A1) and viewing devices such as cameras and light sources (US 9332896 B2).

However, where auxiliary means adding to costs of the equipment required to perform efficiently the state of the art still has not reached its possible maximum when it comes to the positioning of the light source within a laryngeal device and the appliance of the light itself in terms of power consumption, wavelength, radia tion angle and their characteristics.

US 4360008 A discloses a laryngoscope with a light source and a tip 60 with a smooth tissue engaging spatula portion 64 which is pivotable around a hinge pin 62. Said spatula portion 64 forcefully moves epiglottis of the patient to establish a straight line view of the larynx of the patient. No intention of positioning the light source behind the epiglottis of the patient for trans-tissue illumination is reported in this document. According to the self-explaining definition of the word “smooth tissue engaging spatula portion” the construction of laryngoscope in this docu ment has no design for a trans-tissue illumination but seeks rather the opposite - to avoid trans-tissue illumination. EP 3439972 A1 discloses a laryngoscope with an exchangeable sleeve. Said laryngoscope might be provided with visualization means such as a camera. In a preferred embodiment the laryngoscope may comprise a disposable sleeve and a separate reusable camera and light source components. The sleeve may com prise a channel for the camera or light source. In Fig. 1 of this document a cam era and a light source are located towards the distal end of the blade and are pro tected from bodily fluids by the disposable sleeve 7. The position of the camera and the light source would be considered conventional, as they are designed to be proximal of the tip of the laryngoscope blade so that the light source can shine around the epiglottis of the patient to directly illuminate the larynx of the patient.

EP 3439972 A1 uses the term “distal” end for different positions of the laryngo scope. Fig. 1 shows a rectangular emboss in the area of ref. sign 5, where a cam era source is mounted. When disposable sleeve 7 is not part of the laryngoscope but as an add-on then the definition applies for the laryngoscope. Flowever as seen in Fig. 1 the disposable sleeve 7 provides a distal extension which might be transparent according to par. 0044 of EP 3439972 A1. Therefore, the protection of the camera of the laryngoscope from body fluids is done by the disposable sleeve which has no light source at its distal end, respectively the distal elonga tion 8. A trans-tissue illumination cannot be done by the design of this laryngo scope together with the sleeve 7 as a guiding device and the distal elongation 8. EP 3439972 A1 therefore does not disclose a tip light laryngoscope which is adapted for trans-tissue illumination.

US 2003/0168059 A1 discloses a lifter 204 as a mean of keeping tissue away from the light source 212 of the laryngoscope. As seen in Fig. 10 the lifter 204 en ables avoidance of a contact of the light source with the epiglottis of the patient 34. This this construction is not able to perform a trans-tissue illumination.

JP 2005-046565 A discloses laryngoscope with an integrated diode 5 which is able to illuminate the larynx of the patient, the blade front-end and the tip part of a blade with white-luminescence as a means of not discoloring the tissue of the pa tient for the purpose of more accurate diagnostics from the physician. It is not dis closed whether the illumination is indirectly so that the tip itself does not shine or whether the tip of the blade itself transmits light. The second option would mean that the material of the blade would consist of fiberoptic or similar material, which is not disclose by this document. Therefore, an indirect illumination is more likely with the tip has not illumination or light transmittance itself. Therefore, this con struction is not able to perform a trans-tissue illumination.

Likewise, JP 2008-289668 A discloses also a laryngoscope with a light source that indirectly illuminates the tip of a blade, which means that the tip itself does not illuminate light. This construction is not able to perform trans-tissue illumina tion.

US 2009/289668 A discloses an endoscope with an evaluation unit for determin ing the degree of opening of the vocal folds of the patient, which is by definition not a laryngoscope for guiding tracheal intubations.

No construction in the previously cited state of the art is able to provide a trans tissue illumination. Common designs of laryngoscopes try to avoid contact with tissue because the tissue contact will reduce the light intensity of the light source. If a camera is positioned at the tip or near the tip the epiglottis of the patient will be a hindrance for the view. All combined constructions are designed from the state of the art avoid the tissue contact with a light source. In conclusion the de signs cited in the state of the art have are means but without the function for trans-tissue illumination.

It is an object of this invention to seek to mitigate disadvantages such as those described above.

An inventive tip light laryngoscope comprises of a handle and a blade with an end segment and an adjacent tip. A light source is positioned at said tip to enlighten the tissue in front of this tip while contacting it tightly. The light is provided at this position to perform a trans-tissue illumination, preferably when brought in contact with the tissue in the mucosal fold between tongue base and epiglottis called “val lecula.”

In a preferred embodiment of the invention, the distal light source is positioned at the most distal tip of the laryngoscope, especially in insertion operation mode of the laryngoscope. Insertion operation mode means the operation mode when the laryngoscope is ready to be inserted in a patient. This is not the case in US 4360 008 A when the spatula portion is tilted away from the distal position. The same applies US 2003/0168059 A and the lifter in a position tilted away from the blade of the laryngoscope, where it is anatomical impossible to insert the laryngoscope. There might be a camera together with another secondary proximal light source installed at said end segment. The camera and secondary proximal light source can be positioned proximal to the tip of the blade towards the perpendicular line of the axis of the handle, wherein the camera is positioned on a side of the blade, which is curved convex, wherein a means of visualization is utilized to view the image from the camera.

The camera can be equipped to capture an image of a part of the environment to wards said tip, especially of the end section of the blade. This image could be ei ther a photography or most preferably a video image.

The camera can be a miniaturized version, preferably a charged coupled device (CCD) camera comprising a transmission chip for transmitting images and video images taken from the front view of the intubation blade onto an external display screen. Such screen can be provided as a separate unit outside of the laryngo scope or as attached to the laryngoscope handle.

A detachable, separate display screen might be of advantage when it comes to cleaning and sterilization after use. A regular light emitting light source illuminates the environment in front and around the blade tip.

The image might be visualized and interpreted by the operating clinician or auto matically interpreted by an image recognition software that recognizes typical fea tures of the upper airway such as the pharynx, hypopharynx, larynx, glottis, vocal cords, trachea, and bifurcation.

The camera can be manually controlled and operated using provided buttons of the control unit as part of the laryngoscope.

As mentioned above, the laryngoscope comprises a distal light source, also re ferred to as a tip light, mounted at the tip of the blade to enlighten the tissue in front of the tip. In one preferred example the light source can be actuated but it can also be provided without any external or internal actuation means.

The distal light source can be designed in a way or can be mounted to the tip in a way that the direction of radiation of the distal light source can be set in any direc tion to best optimize the targeted tissue illumination. As discussed above, a secondary proximal light source, also which might be pref erably a regular light emitting light source, is mounted onto the blade to further enlighten the environment alongside said blade, wherein the secondary proximal light source is preferably positioned proximal from the distal tip.

As it could be understood from the description there could preferably be at least two light sources for two different purposes integrated in the blade.

The aforementioned secondary proximal light source might be a conventional light source which is inbuilt in every laryngoscope known in the state of the art. It is located towards the end segment of the blade, but not at its tip. Its position can typically be at about 10% of the length of the blade away from the tip, depending on the independent geometry of the blade.

The Trans-Tissue Light at the tip is intended to illuminate the tissue’s inner struc ture. By this the internal glottis structure around the inlet becomes better visible and helps aiming the tracheal tube into the right position. It is preferably not in tended to illuminate the hypopharyngeal cavity around the glottis.

The secondary proximal light source is designed as a conventional light and is preferably positioned further behind (proximal) on the blade has the sole scope to illuminate the hypopharyngeal cavity around the glottis. By this, the user sees the anatomy of the pharynx on the screen and can position the laryngoscope accord ingly. Therefore, the secondary proximal light source has a high advantage for di recting and positioning the laryngoscope.

In a preferred more sophisticated embodiment of the current invention, the ambi ent light, which might be the secondary proximal light source, is dimmable and can be automatically dimmed for example to 50% or less than its initial bright ness, as soon as the tip pf the blade is pressed against tissue and the trans tis sue light goes on. By this, the contrast could be better. In this embodiment the laryngoscope might be provided with a contact sensor for either actuate at least one or preferably both of said light sources. The secondary proximal light source can be dimmed down, while the tip light is switched on when the contact sensor measures a contact with the tissue.

It can be recommended that the ambient light, which is the secondary proximal light source, is turned on during this phase, because anytime a view on the sur- roundings is useful to ensure adequate positioning of the device. The aforemen tioned embodiment is a preferred optimized version of the invention described above.

In the case of a video laryngoscope, where a camera is provided at the blade, it can be placed close to the camera, preferably a CCD camera.

The secondary proximal light source emits only regular, visible light and its scope is to illuminate the surroundings - otherwise the eye of the viewer in conventional laryngoscopes or the camera in video laryngoscopes wouldn’t see anything.

The distal light source at the tip of the laryngoscope can preferably be inbuilt into the tip of the blade and can have a cylindrical or spherical shape, which is adopted to prevent high pressures on the patient during contact and to avoid con tusions. So far, such a light source doesn’t exist in any of the available laryngo scopes. This light can emit visible light as well as NIR light with a defined wave length. The light source can be pushed onto the mucosa and get into direct con tact with it, preferably in the mucosal fold between tongue base and epiglottis called “vallecula”. This means that the laryngoscope is designed accordingly. The terms “designed to”, “configured to” or “adapted to” can be used as exchangeable words with the same technical meaning in the context of the current invention.

The scope of this light is to penetrate the adjacent tissue and to fill it up with the emitted photons in order to produce the “glowing” or “fluorescent effect” of the tis sue, especially when NIR is emitted, and viewed via the camera. If visible light is emitted, direct view with the naked eye might be possible too. The light from this source is explicitly NOT meant to illuminate the anatomical features through the air (as does the conventional light source mentioned above).

This formation is designed for better and more secure guidance of the endotra cheal tube. A direct light at the front of the moving blade illuminates any tissue in front as well as in the light cone causing fluorescence, particularly to an increased level when the light gets in contact with tissue in way of the moving blade. This visible effect will alert the operating clinician to the extend to either visualize, stop or redirect the movement of the endotracheal tube or to examine the object in question upon its normality or abnormality respectively.

The tip light laryngoscope can also comprise an actuator as part of the light source for example. The purpose of the actuator is to move the illumination angle of the light source

The actuator can be any means of actuation which will be manually controlled and operated via the control unit and its actuating element, which can be a joy stick for example. The actuator can also be installed outsight the light source but actuate the light source in order to move the light source in a desired direction.

The tip light laryngoscope can further comprise a control unit which is adjacent to the handle. The control unit can also be an integrated part of the handle. The handle can comprise a power storage to provide electrical power to the camera, the distal light source, the actuator itself and the control unit or any other device, the display screen for example. The power storage can be a compartment or a box which holds any means of power, such as a rechargeable or disposable bat tery for example.

Optionally, the devices consisting of the blade, the camera, and the distal light source including the actuator can be fitted either stationary or mobile. Alterna tively, only the blade can be mobile fitted with an immovable camera and an im movable distal light source and an immovable actuator fixed at defined positions to the blade.

There are multiple advantages for these options. Due to variability in human anat omy, there is no universal size of blade that can be used in all cases. A number of different blades may be desirable and beneficial so that a clinician is able to visu alize a laryngeal inlet with a choice of blade shapes and sizes depending on clini cal requirements, personal expertise and preference.

The first option - all devices fitted mobile - might be more advantageous in terms of costs in comparison to the second one when it comes to a necessary part-ex- change. However, in all cases there is the further advantage when it comes to cleaning and sterilization of the components of the tip light laryngoscope.

Overall, this arrangement has multiple advantages. In conjunction with the view ing means as described above, the advantages can be summarized as giving a better controlled guidance of the insertion process of the tracheal tube, providing more security for the patient as injuries of tissue or other parts of the laryngeal in let potentially caused by a less directly illuminated input path and forward moving blade of a conventional laryngoscope may and can be avoided and ultimately the advantage that this tip light laryngoscope will fit the purpose being a tool for clini cians in training.

In comparison to laryngoscopes of the state of the art the invented tip light laryn goscope might be equipped with such illuminated viewing means and is also cost efficient which adds to the advantages altogether.

Particular embodiments and other and further objects of the invention will be pointed out or indicated in the sub claims hereinafter or will be apparent to one skilled in the art upon an understanding of the invention or implementation of it in practice.

To the best advantage is the embodiment where the camera and the visible light source, also referred to as secondary proximal light source, preferably as regular light emitting light source, are fitted in a back-layered position onto the blade away from the tip, preferably up to 10% of the total length of the blade measured from the tip towards the perpendicular line of the axis of the handle and on the convex curved side of the blade providing an unobstructed view towards the tip.

The distance of the camera lens to the distal edge of the front of the tip can be optimized in a way that it permits the best possible viewing of the pharyngeal structures and the laryngeal opening.

In laryngoscopes according to the state of the art, said tip would possibly touch tissue. Said camera is best positioned backwards from the tip. The tip should be understood the most distal position of blade of the laryngoscope.

An important aspect of this arrangement is that the part of the environment, espe cially the end section of the blade the image is taken of, includes the tip of the blade, thus the tip will be constantly visible as a point of reference.

By this configuration, the clinician may see and visually confirm the passage of the tracheal tube through the vocal cords into the trachea for example. However, the tip light laryngoscope blade does not pass the vocal cords.

The light source at the blade tip can be fitted with a near infrared (NIR) emitting light source or a visible light source or a combination of multiple light sources. When light hits tissue, the effects are in essence reflection, transmittance, disper sion and absorption. In case of absorption, the energy of light will be emitted as heat or fluorescence or phosphorescence. There are a number of absorber in hu man tissue, H20 is one of them and specifically absorbs NIR.

Depending on the wavelength of the light source, and the consistence of tissue the effects vary. However, using NIR light in medical diagnostic it is known to the art that tissue absorbs NIR light with the effect of fluorescence at wavelengths from 780 nm and at low light power output.

It is therefore advantageous if the light source of the tip light laryngoscope can be fitted with a near infrared emitting light, preferably for the distal light source, with parameters of a wavelength in the region 780 nm to 950 nm, preferably a direc tion of radiation of 850 nm, and a power consumption below 500 mW, preferably 140 mW maximum.

But it is also possible that the distal light source and/or the secondary proximal light source can also have a wavelength in the visible light region of between 400 nm and 780 nm.

The distal light source and/or the secondary proximal light source can have any combination of visible light and near-infrared light.

A low power consumption is also beneficial as it processes less operating heat. The light source can be made as a LED or fiberoptic.

It is also of advantage if the distal light source can be fitted centroid at the front of the blade, namely the tip. In this way the light source and the tip form a unit, which can be spherical or cylindrical. Such a position supports and enables a bet ter controllable guidance and avoids the need for any kind of determination of the actual position of the tip of the blade if the light source were fixed differently for example.

The end cap of the blade can be formed spherical or cylindrical. Thus, the tip of the blade will have no sharpness of edges, which further contributes to avoiding potential injuries of tissue for example, when positioning or moving the blade whilst inside the patient. The centroid wavelength can be arrayed in such direction that it forms a normal of the spherical front cap. This array will be of advantage and in line with aforemen tioned layout of the centroid position of the light source.

The distal light source can be defined in such way that the radiation characteris tics are of up to 15° of the direction of radiation of the near infrared emitter light source. This is of advantage as it creates a wider viewing angle around the end of the blade although the detection intensity decreases in relation to the increase of the angle due to the radiation characteristics.

It is therefore advantageous when the light source is either fitted or equipped with an actuator to direct the light cone of the light source using the actuating element of the control unit, such as a joystick, preferably up to at least 45°. Thus, the view ing angle can be made broader around the tip of the blade in any direction.

It is of advantage when the blade or the distal light source is fitted with a tempera ture sensor to configure the operating temperature of the distal light source in a range of 30° C to 40° C, preferably in the range of normal human temperature be tween 35,7° C and 37,3° C.

The temperature sensor together with a potentially fitted temperature compensa tion unit that adapts the distal light source operating temperature to an environ ment, the laryngeal inlet of a human for example, can be regarded as considera ble advantage as it makes the usage of such a tip light laryngoscope safe as to the requirements by law and subsequent ordinances and regulations.

The temperature compensation unit can be an integrated part of the control unit or designed as a separate device.

Also, the distal light source can be miniaturized with dimensions less than 1 ,5 mm in diameter and less than 1 ,75 mm in height.

The blade of the tip light laryngoscope can be shaped in a commonly known way, for example having a thickness double the size next and adjacent to the perpen dicular line of the axis of the handle in comparison the one at the tip and prefera bly having a curved portion with a convex and concave side to smoothly follow and conform to the anatomical shape of a patient’s airway.

It is advantageous to have the blade of this tip light laryngoscope shaped in a commonly well-known way, not only due to anatomical reasons but especially when using the tip light laryngoscope for training purposes. A clinician in training will recognize the instrument as such and what it is used for and can instantly concentrate on the specific features applied to it and familiarize with those.

The blade can be manufactured in different materials, for example metals or plas tics in which case it could be made opaque or transparent.

The blade along with any attached components including the distal light source can be disconnected from the handle to be cleaned for sanitation or for being dis posed.

In a further embodiment the tip light laryngoscope can also comprise a second light source. This second light source can be mounted onto the blade to further enlighten the environment, for example positioned adjacent to the camera.

However, this second light source can also be fitted behind the camera or side- wise of the camera.

An advantageous embodiment of an inventive tip light laryngoscope is further ex plained in detail by a drawing. Specific parts of the embodiment can be under stood as separate features that can also be realized in other embodiments of the invention. The combination of features described by the embodiment shall not be understood as a limitation of the invention:

Fig. 1 a schematic view of the tip light laryngoscope;

Fig. 2 an illustrated view of the light cone and the central direction of radiation;

Fig. 3 an illustrated view of the potential directions of the light cone;

Fig. 4 schematic drawing of an actuated light source;

Fig. 5 position of the laryngoscope in a person showing the effect of illumination due to the position of the light source at the tip of the laryngoscope.

An embodiment of an inventive tip light laryngoscope 1 according to the invention is shown in Fig. 1-3. The tip light laryngoscope 1 comprises a blade 2 which can preferably comprise a camera 3 for taking an image of a part of the environment alongside and in front of an end segment 4 of the blade 2 with a tip 5 and an dis tal light source 6 at the tip 5 to enlighten the environment in front of the tip 5. The tip light laryngoscope 1 further comprises a handle 7 and a control unit 8a. The control unit 8a is provided with buttons to operate the camera 3 and the distal light source 6.

The control unit 8a is further equipped with an actuating element 8b, such as a joystick, to direct the light cone 12 of the distal light source 6 with an equipped ac tuator 11 in angular directions of preferably up to 45° as illustrated in Fig. 3.

The effect is broadening the viewing angle in contrast to a non-distal light source.

The position of the camera 3 is defined to be up to 10% of the total length of the blade 2 measured from the tip 5 towards the perpendicular line of the axis of the handle 7 and on the convex curved side of the blade 2.

The view of said camera 3 is such that the part of the environment, especially the end segment 4 of the blade 2 an image will be taken of, includes the tip 5 of the blade 2, thus the tip 5 will be constantly visible.

The camera 3 can be a charged coupled device (CCD) camera equipped to take an image of a part of the environment in front of an end segment 4 of the blade 2 with the tip 5 visible, preferably a video image.

The camera 3 can comprise a transmission chip for transmitting images and video images taken from the front view of the intubation blade onto an external display screen.

The control unit 8a can comprise an image recognition software that recognizes typical features of the upper airway by pictures detected by said camera 3.

The distal light source 6 is defined as being a near infrared emitter light source. Further defined as being fitted centroid and partly spherical forming a spherical front cap 9 of which a direction of radiation 10 forms a normal. This formation is illustrated in Fig. 2.

The distal light source is further defined being fitted with a near infrared emitter light with a direction of radiation 10 preferably of 850 nm, and a low power con sumption such as 140 mW maximum in order to achieve the effect of fluores cence on tissue when operating the tip light laryngoscope 1. Fig. 1 further shows that in a preferred embodiment the distal light source 6 com prises a temperature sensor 13 to configure its operating temperature scale, pref erably between 35,7°C and 37,3 °C.

Fig. 1 also reveals that the tip light laryngoscope 1 comprises a temperature com pensation unit 14 integrated in the control unit 8a that adapts the distal light source 6 operating temperature to an environment, the laryngeal inlet of a human for example.

The temperature sensor 13 and temperature compensation unit 14 are matters of safety.

The blade 2 is defined by a first thickness next and adjacent to the perpendicular line of the axis of the handle 7 and a second thickness at the tip 5 in that way that the first thickness is at least double the size of the second.

The tip light laryngoscope 1 can be fitted mobile in a way that the blade 2 can be detached from the handle 7 in order to apply variations of blades in shape and size.

The blade 2 itself can be mobile fitted with an immovable camera 3 and an im movable distal light source 6 fixed at defined positions to the blade 2.

As an option, the devices consisting of the camera 3 and the distal light source 6 and the actuator 11 can also be fitted mobile.

The tip light laryngoscope can be fitted with a second light source 15 either mounted on top of the camera 3. Alternatively, the second light source 15 can be fitted behind or sidewise of the camera 3.

The tip light 5 in Fig. 1 might be describe as cylindrical in the sense that it is aligned along the tip of the blade. It has an aperture with a limited angle.

The tip light of Fig. 1 might have a distinct opening angle, which should be up to 35° but not more. The scope of this rather narrow cone is to direct the light more into the tissue as shown in Fig. 5 and to avoid escaping into the surroundings.

The direction of the tip light beam might be as a continuation of the blade, or in a specific angle downwards see Fig. 1 e.g. by 30°. The tip light might be equipped with LED units with different wavelengths and the actual combination of emitted light wave length may be variated by the user, ei ther by setting changes or by a dedicated switch. The same might be true for the light intensity.

Fig. 4 discloses an example of an actuated light source 6, where the light cone can be moved by an actuator such as a partly spherical actuator which can be moved inside a transparent housing in the same manner as a ball-joint. The light source 6, such as an LED, can be connected to this actuator 11 and thus the light cone of the light source can be moved in any suitable direction. The housing can be further provided with the said temperature sensor 13 at a position where the light will be guided through the housing, thus heating the housing to a certain amount.

In a further embodiment, the tip light laryngoscope can be provided with a contact sensor, wherein the tip light is switched on only when the tip is in contact with a tissue, which is the case in Fig. 5. It might be also possible that the tip light can be switched on by a switch at the handle or near the handle of said laryngoscope. For an orientation the environmental light provided by the second light source, for example at the camera, can be always switched on.

Most preferably the control of the first and the second light source can be done in dependently from each other as described by the aforementioned examples.

One further aspect of the current invention is a method for performing guided tra cheal intubation in preparation and/or during the introduction of an endotracheal tube on a subject with an inventive tip light laryngoscope.

Said method comprises the step of internally illuminating the tissue of the subject in the region of the subject's vallecula with the light source at the tip of said laryn goscope which is brought in contact with said tissue, where the illumination is en hanced by the anatomical structure of the subject in this region. This step is pro vided to facilitate the guiding of an endotracheal tube during its introduction.

Further according a part of the current invention is a method for performing guided tracheal intubation for the introduction of an endotracheal tube on a sub ject with the an inventive tip light laryngoscope comprising; internally illuminating the tissue of the subject in the region of the vallecula with the light source at the tip of said laryngoscope which is brought in contact with said tissue in the muco sal fold, where the illumination is enhanced by the anatomical structure of the subject in this region and hence facilitating the guiding of an endotracheal tube.

Reference numeral

1 laryngoscope

2 blade 3 camera

4 end segment

5 distal tip

6 distal light source

7 handle 8a control unit

8b actuating element

9 spherical front cap

10 direction of radiation

11 actuator 12 light cone

13 temperature sensor

14 temperature compensation unit

15 secondary proximal light source

16 trans-tissue illumination