Patent Application
20180104014
The present invention relates to a surgical drape for separating a sterile region from an unsterile region during surgery and a method of utilizing such surgical drape during patient registration.
In medical procedures incorporating image-guided surgery (IGS), is desirable to know the position of a specific anatomical structure that can be seen in the medical image of the body of a patient who is to be treated, with respect to the actual patient's body. It is likewise desirable to know the relative position of medical equipment such as medical instruments and a specific anatomic structure that is shown in a medical image of the body of the patient. For both reasons, patient registration procedures have to be performed by means of which the actual body is registered to the at least one medical image. This will allow a medical navigation system to display the position of the anatomical structure relative to the surgical instrument to medical personnel on a monitor.
However, such registration procedures must not compromise sterility of the workplace. Conventional registration methods are therefore performed pre-operatively and prior to draping of the patient. Registration cannot be repeated, for example to restore an initial registration intra-operatively, after the patient has been draped, since anatomical landmarks, structures and artificial fiducials have also been covered by the drape and are therefore inaccessible. WO 2005/002456 A1 suggests to provide a surgical drape having covering elements for reference means that allowed to track the reference means intra-operatively. This, however, does not allow for re-registering the patient intra-operatively, as well.
The present invention provides a surgical drape and a method of registering a patient's body part, that allow to register a patient's body part intra-operatively after it has been covered by a surgical drape prior to surgery.
The inventive surgical drape and the inventive method of registering a patient's body part are defined by the appended independent claims. Advantages, advantageous futures, advantageous embodiments and advantageous aspects of the present invention are disclosed in the following and contained in the subject-matter of the dependent claims. Different advantageous futures can be combined in accordance with the invention wherever technically expedient and feasible. Specifically, a feature of one embodiment which has the same or a similar function to another feature of another embodiment can be exchanged with said other feature. A feature of one embodiment which adds an additional function to another embodiment can in particular be added to said other embodiment.
The surgical drape according to the present invention comprises:
The inventive surgical drape comprises an impervious section having absorbing properties which is already known from prior art surgical drapes and which has a layer configured to absorb body fluids, and a further layer that is configured to provide an impervious barrier preventing any substance to penetrate the impervious section of the surgical drape. For example, the impervious layer may be a layer of the impervious section adjacent to an unsterile section underneath the drape covering the patient, whereas the absorbing section may face towards the sterile workplace. Moreover, the inventive surgical drape comprises an incision section having an incision foil which may have adhesive properties on one side to stick the incision section down on the patient's skin right next to the incision area. Additionally to the impervious section and the incision section, the inventive surgical drape further comprises a transparent section trough which medical personnel can see the patient and medical equipment covered by the drape to such an extend so that a registration procedure can be performed on a body part of the patient. For this purpose, the transparent section allows a surgeon to immediately see any anatomical or artificial landmarks the position of which has to be determined for registration.
The transparent section may therefore be sized such that substantially a whole body part to be registered, particularly a structurally stable body part such as a head, a thigh, a lower leg, an upper arm, a forearm or a pelvis covered by the surgical drape (1) can be visually observed.
According to this aspect, the size of the transparent section corresponds to the size of the body part to be registered. For surgery performed on a human head, the transparent section may therefore be sized such that the whole head can be observed through the transparent section, whereas for knee surgery, for example, the transparent section can be sized such that a substantial part of the thigh as well as a substantial part of the lower leg can be covered by and observed through the transparent section of the surgical drape.
The same applies to the shape of the transparent section which can correspond to the shape of the patient's body part to be treated. For example, a surgical drape used for head surgery can have a transparent section with a round or an oval shape, whereas a drape for operations performed on a human leg may have a transparent section with a longitudinal shape.
For example, the size the transparent section can amount to more than 20% of the overall size of the surgical drape or even to more than 30% of the overall size of the surgical drape.
The transparent section may be positioned relative to the incision section of the surgical drape in any expedient manner. For example, the transparent section and the incision section can form two windows in the surgical drape separated by an impervious section. Another example of the surgical drape may however have an incision section and a transparent section which lie adjacent to each other. A further example of the inventive surgical drape can have an incision section surrounded by a transparent section which in turn forms a window within the surgical drape.
It is evident from the description that the transparent section of the inventive surgical drape may have any form and size that appears to be expedient for a specific surgical procedure to be performed.
Further, the surgical drape can be pre-assembled, for example by gluing the impervious section, the incision section and the transparent section together. Moreover, the surgical drape can have the form of a sheet that extends in two dimensions without having any bulge or pouch.
Another example of the inventive surgical drape comprises fixation means that releasably hold together a compacted area of the surgical drape's transparent section, for example a folded, pleated or rolled area. This will allow, medical personnel to increase the size of the transparent section up to a size that is deemed to be appropriate for a specific procedure performed. For example, the transparent section of the surgical drape can be provided with Velcro-straps or adhesive straps that hold a certain portion of the transparent section together, and may be released in case a lager transparent section is needed.
A further aspect of the present invention relates to a method of registering a patient's body part with a pre-acquired image dataset of the body part, comprising the following steps:
As already explained further above, the inventive registering method makes use of a transparent section of a surgical drape that allows any medical personal to visually observe a patient's body part and medical equipment through transparent section of the surgical drape for registration purposes.
Again, it is noted that for registration purposes, it is necessary to see large parts of the patient's body together with natural landmarks of artificial fiducials attached to the body part through the drape, so that these landmarks or fiducials can be approached and palpated fast and easily with a registration instrument.
The inventive method can be performed with an unsterile registration instrument held and moved by a user within an unsterile area. In other words, landmarks or fiducials are palpated with an instrument held under the surgical drape, wherein the user can see the instrument through the transparent section of the surgical drape. In case the instrument is tracked via optical tracking cameras, the surgical drape's transparent section has to be translucent for the wavelengths used by the tracking cameras.
In the alternative, the inventive method can also be performed with a sterile registration instrument held and moved within the sterile workplace, i. e. above the surgical drape. In this case it is only necessary to see substantial parts of the patient's body part together with the landmarks or fiducials through the transparent section of the drape, so that the registration procedure can be performed fast and easily.
The inventive method can also comprise a surface matching procedure for which the surgeon sweeps the tip of a registration instrument over the patient's skin so as to determine its form and position. On the other hand, the registration can be performed by palpating predetermined natural landmarks or artificial fiducials for matching them to corresponding landmarks or fiducials, respectively, which can be identified in an image or an image data set of the patient.
With the large transparent section providing the possibility to observe whole body parts of the patient through the surgical drape, it is evident that the registration procedure can be performed prior to surgery as well as during a surgical procedure, for example as a re-registration. In both cases it is possible to attach artificial fiducials onto the patient's skin before the patient is covered with the surgical drape.
With a surgical drape having a size-adjustable transparent section that can be used for a multitude of surgical procedures requiring different sizes of the transparent section, medical personnel can adjust the size of the transparent section by at least partially releasing the fixation means holding together a compacted area of the transparent section.
In the following, the invention is described with reference to the figures which represent preferred embodiments of the invention without limiting the invention to the specific features shown in the figures.
The surgical drape 1 shown in
It is important to note that incision section 3 does not necessarily have to be entirely surrounded by the transparent section 4 but may also, at least partially, border directly to the impervious section 2 of the surgical drape 1. Moreover, it is to be noted that the size and shape of the impervious sections 2, the incision section 3 and the transparent section 4 as shown in the Figures are arbitrary and that these sections may have any form or size that appears to be suitable for a specific surgical procedure the surgical drape is designed for.
One embodiment of the inventive registration method is illustrated in
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2015/055558 | 3/17/2015 | WO | 00 |
