Minimal Invasive Endoscopic Ear Surgery: A Two Handed Technique

Abstract

To evaluate the surgical outcome of two handed technique of endoscopic ear surgery with endoscope holder. Retrospective Non Randomized Clinical Study. A total of 547 endoscope holder (Justtach) assisted ear surgeries (331 cartilage tympanoplasties and 216 cholesteatoma surgeries) were operated with Justtach from July 2013 to April 2016 with a follow up period ranging from 12 to 45 months to evaluate its feasibility and results with the technique. The design of the endoscope holder, Justtach is described along with its functioning and maneuvering techniques. In the endoscopic tympanoplasty group, at 1 year follow up, the graft uptake was seen in 323 ears with three residual perforation and 5 recurrent perforations giving a success rate of 97.58%. At the 2 years follow up, the graft uptake was in 322 ears with 6 recurrent perforations and 3 residual perforations with a success rate of 97.28%. Whereas in case of endoscopic cholesteatoma surgery, there was residual cholesteatoma in 5 and recurrent in 6 out of 216 cases. The study reports the successful application and use of endoscope holder in two handed technique of endoscopic ear surgery.

Level of Evidence Level 4.

Electronic supplementary material

The online version of this article (10.1007/s12070-018-1411-7) contains supplementary material, which is available to authorized users.

Introduction

Minimal invasive surgery has influenced the techniques in every specialty of surgical medicine. This has led to the replacement of conventional procedures with minimally invasive ones, stimulated surgeons to re-evaluate conventional approaches. However, two major drawbacks of the minimal invasive surgery include the prolonged learning curve for most surgeons, and secondly, increased costs due to investment in the equipment required as well as longer operating times. Since the introduction of microscope in middle ear surgery, all the well-established techniques in ear surgery have evolved. However since last decade, endoscopes have been introduced into ear surgery. Endoscopic ear surgery is an evolving science in the field of otology and provides minimally invasive transcanal approach to the middle ear. Though endoscopic techniques are similar to the standard well known microscopic ear surgery techniques, it differs in its approach to the middle ear and adds a new perspectives and dimensions to the understanding of middle ear anatomy and pathology. The advantages of endoscopes in ear surgery include (1) visualization of the whole tympanic membrane and the ear canal without manipulation of the patient’s head or the microscope, (2) extension of the operative field in transcanal procedures into structures usually hidden from the microscope (anterior tympanic perforation, posterior retraction pocket, facial recess, and hypotympanum) and (3) visualization of structures from multiple angles as opposed to the microscope’s single axis along the ear canal [1, 2]. In cholesteatoma surgery, the use of endoscopes has reduced the incidence of residual disease [3].

The only disadvantage of endoscopic ear surgeries as compared to microscopic ear surgery is that it is single handed surgical technique in which the non-dominant left hand of the surgeon is utilized for holding and manipulating the endoscope. The problem of one handed endoscopic ear surgery is more evident during drilling (in which simultaneous suction and drilling is not possible) hemorrhage (simultaneous suctioning and instrumentation is not possible), during fogging of the endoscope (one needs to remove endoscope again and again for lens cleaning), during prosthesis fitting in ossiculoplasty (manipulation may be difficult with one hand). In these situations, one feels the immense need for the two handed technique as in the microscopic ear surgery. Development of the endoscope holder would solve the single handed difficulties. Hence, the first endoscope holder, EndoHold [4] (Patent Application No. 2313-Mum-2013) was developed. The first endoscope holder is a modification of the microscopic stand. Endoscopic ear surgery (EES) is still in its developing stage. Though endoscope offers lot of advantages in middle ear surgery, but many a times, the surgeon, in the initial days of endoscopic ear surgery, may be compelled to shift to the microscope to visualize the magnified middle ear structures or for drilling. This necessitated the development of the second patented endoscope holder attachment to microscope which would allow both hands of the surgeon to be free for surgical manipulation during EES and allow alternate use of microscope whenever needed during ear surgery [1, 4, 5]. Operating Microscopes have range of motion in space during otological surgeries for focusing the desired object for magnification. This whole range of motions can be applied for driving the endoscope smoothly in any biological cavities once an endoscope holding attachment is fixed to optical system of any operating microscope (Patent Application No. 3300-Mum-2013) [5]. The purpose of this study was to report our experience of our minimally invasive two handed technique of endoscopic ear surgery with the second endoscope holder, Justtach.

Methods and Materials

From 2010 to 2013, we operated with the single handed technique of Endoscopic Ear Surgery. However, due to the technical difficulties of the single handed surgery, we developed two endoscope holders; Patent Application No. 2313-Mum-2013 or EndoHold [4] and Patent Application No. 3300-Mum-2013 or Justtach [5]. This study includes exclusively the endoscopic ear surgeries operated with the second endoscope holder, Justtach [5]. A total of 331 endoscope holder assisted endoscopic cartilage tympanoplasties and 216 primary cholesteatoma surgeries were operated from July 2013 to April 2016 in M.I.M.E.R Medical College and Sushrut ENT Hospital with a follow up period ranging from 12 to 45 months. There were 281 males and 266 females in the study group. The mean age of the study group was 29.32 ± 4.31 years. The youngest patient was 9 years of age and the oldest was 56 years of age. Written consent was taken in all the patients. The details of the operative procedure was explained to the patients. The Institutional review Ethics Committee has approved the study. The average preoperative Air–Bone–Gap in the study group was 31.32 ± 3.76 dB in the pars tensa perforation group. Part of the study has been already published [5]. In the cholesteatoma group, the average preoperative Air–Bone–Gap was 35.68 ± 5.69 dB.

Design of Endoscope Holder (Justtach-Patent Application No. 3300-Mum-2013) [5]

It is a metallic plate of 170 × 70 × 12 mm in dimensions with a circular slot measuring 16 × 16 mm in diameter to hold rigid endoscope and square slot to hold onto the microscope (Fig. 1). It has to be fixed to the optical system of any operating ENT microscope with the built in tightening screws (Fig. 2).

Fig. 1.

Justtach

Fig. 2.

Justtach attached to microscope for two handed EES

Operating Theatre Requirements and Preparation of the Patient

Zero degree 4 mm endoscope with triple charge coupled device Camera (Karl Storz, Germany) is firmly fixed to optical system of microscope just above objective lens.

The ear canal is infiltrated with 2% lidocaine with 1 in 2,00,000 adrenaline. All patients of cholesteatoma surgery were operated under general anaesthesia and in the cartilage tympanoplasty group all, except 32, were operated under local anaesthesia. Preoperatively, all the patients were explained about the endoscopic procedure. Intraoperatively, the head of the patient is steadied by the assistant by placing the hand over the head of the patient to avoid any accidental head movement [4, 5].

Procedure [5] of Endoscopic ear Surgery with Justtach™ (Figs. 3, 4, 5, 6, 7, 8)

Fig. 3.

Tragal cartilage graft harvest

Fig. 4.

Transcanal zero degree middle ear endoscopy

Fig. 5.

Ventilation pathway check

Fig. 6.

Sliced cartilage graft view after the tympanomeatal flap reposition

Fig. 7.

a Drilling with the two handed technique of ear surgery. b Atticoantrostomy and clearance of cholesteatoma with only stapes superstructure present. c Atticoantrostomy and clearance of cholesteatoma with no ossicles

Fig. 8.

a Sliced cartilage graft placed over stapes superstructure after atticoantrostomy. b Tragal cartilage graft for ossiculoplasty

Instruments used in two handed endoscopic ear surgery are the same as in microscopic ear surgery. Using all aseptic precautions, the hair in the ear canal are trimmed with the 15 number surgical blade. The ear canal is irrigated with normal saline solution to clean any debris.

Incision and Approach

In endoscopic cartilage tympanoplasty, permeatal (transcanal) incision is taken. In cholesteatoma cases, either transcanal (for limited attic cholesteatoma) or an endaural incision (in extensive cholesteatoma surgery) is taken.

Tragal Cartilage Harvest and Graft Preparation

Tragal cartilage is the graft of choice. It is harvested via the horizontal incision on the tragus in case of transcanal incision (Fig. 3). When endaural incision is taken, the tragal cartilage is harvested via the vertical limb of the Lempert’s endaural incision. The tragal cartilage perichondrium graft is sliced [1, 5–11] with Slice !t^®(Dr. Khan’s Creations, India) to 0.5 mm thickness.

Middle ear Disease Clearance and Function Restoration

Intraoperative evaluation of middle ear anatomy during endoscopic surgery for inflammatory pathology allows to clearly visualize the presence of an anatomic blockage of ventilation pathway. The middle ear is evaluated (Fig. 4) for any presence of glue, cholesteatoma, granulation or block in the ventilation pathway (Fig. 5). The sliced cartilage graft is then placed by underlay technique (Fig. 6). In cholesteatoma surgery, the inside out technique of mastoidectomy is used to chase the cholesteatoma (Fig. 7a–c) and to excise the cholesteatoma. The atelectatic tympanic membrane or cholesteatoma matrix is elevated. The squamous epithelium loosely adherent to the neck of the malleus and scutum allows for a good starting point for surgical dissection. In the two handed technique of EES, the suction is held in left hand to avoid the fogging and also to achieve cooling of endoscope. Intermittent irrigation is done for cleaning and cooling of endoscope [1, 4, 5]. The stability rendered to the endoscope with the endoscope holder aids and augments the technical usage of endoscope in ear surgery during all steps of the routine tympanoplasty. With endoscope holder, Justtach, the simultaneous drilling and suctioning is possible. The panoramic view of the endoscope allows the visualization of the pathology beyond the corners without much bone removal. The angled endoscopic view allows complete removal of cholesteatoma from hidden areas like aditus, facial recess, or sinus tympani without much bone removal. The ossiculoplasty with cartilage graft is done in patients with ossicular erosion (Fig. 8a, b). Soft wall reconstruction is done in atticoantrostomy canal wall defect. In case of narrow canal, we used 3 mm zero degree designed Karl Storz endoscope of 14 cm length [1, 4, 5].

Results

A total of 547 two handed endoscopic ear surgeries were operated with Justtach (331 cartilage tympanoplasties and 216 cholesteaoma surgeries have been operated from July 2013 to April 2016 with follow up period ranging from 12 to 45 months (Table 1). No middle ear injury is reported in our series. In all cases of endoscopic cartilage tympanoplasties, a transcanal incision was taken. In endoscopic cholesteatoma surgery, transcanal incision was taken in 173 ears and endaural incision was used in 43 ears. The extent of the disease dictated the amount of drilling and bone removal. In our series of endoscopic cholesteatoma surgery with Justtach, cholesteatoma was limited to the attic in 72 ears (33.33%), beyond antrum in 107 ears (49.54%) and extensive cholesteatoma up to tip was seen in 37 cases (17.13%). Hence in our study of endoscopic cholesteatoma surgery with two handed technique, atticotomy was performed in 72 ears, atticoantrostomy in 107 ears and endoscopic inside out mastoidectomy in 37 ears. At 1 year follow up, the graft uptake was seen in 323 ears with three residual perforation and 5 recurrent perforations giving a success rate of 97.58%. At the 2 years follow up, the graft uptake was in 322 ears with 6 recurrent perforations and 3 residual perforations with a success rate of 97.28% (Table 2). The average preoperative Air–Bone–Gap in the study group was 31.32 ± 3.76 dB and post-operative AB gap closed to 9.34 ± 3.32 dB at 2 years (Table 3). Part of the study [6] has been already published. The results of our endoscopic cartilage tympanoplasty was comparable to our published microscopic primary cartilage tympanoplasty [6] outcome. Whereas in case of endoscopic cholesteatoma surgery (Figs. 9 and 10), there was residual cholesteatoma in 5 and recurrent cholesteatoma in 6 cases out of 216 cases. The average preoperative Air–Bone–Gap in the cholesteatoma study group was 35.68 ± 5.69 dB and post-operative AB gap closed to 26.76 ± 5.39 dB (Table 4).

Table 1.

Age gender distribution of the study population

Operation performed	Number of ears
	Male	Female	Total
Cartilage tympanoplasty	170	161	331
Cholesteatoma surgery	111	105	216
Total	281	266	547

Table 2.

Graft uptake of endoscopic cartilage tympanoplasty

Cartilage tympanoplasty	1 year	2 years
Graft uptake	323	322
Recurrent	5	6
Residual	3	3
Success rate (in percent)	97.58	97.28

Table 3.

Pre and postoperative airbone gap in endoscopic carilage tympanoplasty for pars tensa perforations

Avg preop AB Gap (dB)	Postop ABG 6 months	Postop ABG 1 year	Postop ABG 2 years
31.32 ± 3.76	9.75 ± 4.67	9.04 ± 3.17	9.34 ± 3.32

Fig. 9.

Preoperative patient of cholesteatoma

Fig. 10.

Postoperative view after reconstruction with cartilage

Table 4.

Pre and postoperative airbone gap in cholesteatoma operated by endoscopic atticoantrostomy

Avg preop AB gap (dB)	Postop ABG 6 months	Postop ABG 1 year	Postop ABG 2 years
35.68 ± 5.69	25.65 ± 5.65	25.14 ± 5.27	26.76 ± 5.39

Discussion

The middle ear surgical techniques have evolved and developed after the introduction of the operating microscope. Since last few decades, endoscopic ear surgery also has started gaining popularity. In the initial years, the use of endoscope in ear was limited only for photography, documentation and for diagnostic purposes. Nomura [12, 13] and Takahashi [12, 14] reported first trans-tympanic middle ear endoscopy. Diagnosis of perilymphatic fistulae by transtympanic endoscopy was reported by Poe and Bottrill [12, 15]. The value of endoscopy as an adjunct in cholesteatoma surgery was documented by Badr-el-Dine [12, 16] and El-Messelaty [12, 17] to reduce the risk of recurrence of cholesteatoma. Yung [12, 18] and Ayache [12, 19] confirmed reduction of residual cholesteatoma by use of endoscope in middle ear surgery. Baki [12, 20] used endoscope to evaluate sinus tympani pathology. Endoscopic assisted surgery of the petrous apex was reported by Mattox [12, 21].

Minimal invasive endoscopic and endoscope assisted otologic surgeries are increasingly being performed. The introduction of endoscopes in middle ear surgery has not only changed the surgical approach but also has distinctly reduced the occurrence of residual cholesteatoma due to better visualization of the sinus tympani, facial recess and epitympanic recesses [1, 2, 4–6].

At present, the scenario of the endoscopic ear surgery is a single handed procedure with the endoscope being held in the non-dominant hand of the surgeon and the instrumentation in the dominant hand. We have been operating with the two handed technique of ear surgery using Justtach [1, 4, 5] due to its obvious benefits. In our study, we did not have any trauma to the middle ear structures due to any jerky movements of the endoscope. Neither was there any reported case of middle ear trauma or damage to endoscope tip.

The use of Justtach allows: [4, 5]

1. Allows two handed Endoscopic ear surgery (EES) similar to micro ear surgery as both the hands are available for surgical manipulation.

2. All movements (not functions) of the microscope optical body for endoscope movement can be applied to endoscope holder.

3. With Justtach, the endoscope can be moved more or less similar to the pattern of working of the left hand.

4. Every ENT surgeon owns microscope for ear surgery. With Justtach™, the microscope can be converted into endoscope holder. (At present nobody in the world is doing this) with simply fixing one endoscope holding metallic plate.

5. One can shift to microscopic ear surgery as and when needed with Justtach.

6. As ENT surgeons are well versed with the two handed technique of microscopic ear surgery, hence incorporating the Justtach for two handed EES will not be difficult.

Advantages of our Justtach [4, 5]

1. Due to endoscope holder there is stability of the endoscope, camera and image on the monitor is ensured throughout.

2. No surgeon fatigue in holding the endoscope (as compared with single handed endoscopic ear surgery).

3. When angled endoscope (30, 45, 70 degree) is used with the endoscope holders, it allows better visualization of sinus tympani, facial recess, anterior tympanic cavity and hypotympanum with just rotation of the endoscope within the Holder.

4. All the steps of the ear surgery are similar to Microscopic ear surgery as the left hand holds the suction cannula continuously and the instruments in the right hand.

5. Justtach can be used effectively without compromising the surgical field.

6. As an effective alternative for documentation and a useful teaching aid.

7. Minimizes the need for assistance.

8. As Justtach™ is designed on the Microscopic Stand, the fine focus of the microscopic stand can be utilized for additional advancing into the external auditory canal.

9. No retro auricular incision.

10. No Mastoid bandage is not required.

11. Lesser duration of surgery as the time required for the retro auricular incision and suturing is avoided.

12. Fogging of the endoscope is avoided by use of suction cannula and by irrigation.

13. Canalplasty can be done with the drill in the right hand and suction in the left hand.

Disadvantages and Our Solutions to It [1, 4, 5]

1. In narrow canal, either 3 mm zero degree endoscope or canalplasty may be performed.

2. Simple techniques used by us to avoid thermal damage.

3. The endoscope is kept at the isthmus of external auditory canal.

4. Continuous suction is held in left hand during the procedure as suggested in previous study [22].

5. Intermittent irrigation helps in the cooling effect and cleaning of the tip of the endoscope. It also avoids frequent taking out of the endoscope for defogging (as in single handed endoscopic ear surgery) [22].

6. Additional cost of the endoscope holder in addition to the routine ear instruments.

7. Care is to be taken to avoid accidental injury due to head movement to the tip of the endoscope. For cases operated under local anesthesia with intravenous sedation, the assistant steadies the head of the patient.

Endoscopic techniques permit transcanal exploration of disease-containing area without opening areas that are not involved by cholesteatoma. The transcanal endoscopic approach opens only diseased areas, preserves many healthy air cells, and leaves the cortical bone intact. It also allows one to create two separate cavities; a small reconstructed tympanic cavity that conducts sound through the middle ear and is small enough to be serviced by the (usually dysfunctional) eustachian tube, and a larger attic, antrum, and mastoid cavity, which is joined to the ear canal and exteriorized [2, 12].

Study by Harugop et al. [23] has compared results of single handed endoscopic tympanoplasty with microscopic tympanoplasty with successful outcome in the 82% in the endoscope group 86% in the microscopic group. The surgical outcome was comparable in both the groups, however in terms of cosmesis and post-operative recovery, the endoscope group fared better. In a study by Furukawa et al. [24], endoscopic and microscopic view was analysed. The endoscopic view had clear advantages in terms of entire tympanic membrane visualization in a single field with clear visualization of the perforation edges even when the ear canal was curved. This facilitated reliable refreshing of the perforation edges and grafting. The anterior edge of the perforation was not visible under microscopy in 5 of 25 ears. They performed transcanal endoscopic myringoplasty successfully with a simple underlay technique or with an intracanal incision in cases of marginal perforation. Till now, all the studies mentioned in the literature are those of single handed endoscopic ear surgery. This is the first study which describes the role of endoscope holder, Justtach in two handed endoscopic ear surgery.

The learning curve for endoscope holder aided endoscopic ear surgery may not as steep as that for routine endoscopic or microscopic surgery. All of us are trained in microscopic ear surgery during the post-graduation course of otolaryngology. The microscopic ear surgery is a two handed technique in which one holds the suction in the left hand and the micro ear instruments in the right hand. Our two handed technique also is similar to the microscopic ear surgery with the added advantages of the endoscope. With sufficient training and practice the technique may be adopted by all. Many experienced with endoscopic surgeries will find the technique easy to master, but surgeons who have limited themselves to an entirely microscopic otology practice are likely to find endoscope holder aided endoscopic surgery more difficult or unnecessary to perform or master. Before starting the endoscopic ear surgery, we insist that the surgeon should perform, at least 5 cadaveric endoscopic temporal bone dissection [1, 4, 5].

In the early days of endoscopic ear surgery, the case selection plays a very important role to develop confidence and to master the skills. The initial cases should be endoscopic ventilation tube insertion (grommet), myringotomy and then gradually progress and proceed to endoscopic tympanoplasty for small pars tensa perforations. After the comfort level with the technique increases, one may proceed to performing endoscopic tympanoplasty for large pars tensa perforations and later on to endoscopic cholesteatoma surgery. In cholesteatoma surgery too, one should start with limited cholesteatomas and then extensive cholesteatoma surgery. In two handed endoscopic cholesteatoma surgery, endoscope holder adds to the advantages as compared to traditional mastoidectomy. It is a minimally invasive surgical approach in terms of incision, bleeding, drilling, postoperative pain and healing, and it is curative in terms of the radical eradication of the pathology including hidden areas poorly accessible and thus overlooked by a microscope. As compared to the single handed technique, drilling simultaneously along with suctioning is possible with the endoscope holder.

Conclusion

In the era of minimally invasive surgery, we have designed and developed the endoscope holder, Justtach for overcoming the disadvantages of the single handed endoscopic ear surgery. The advantages and disadvantages of the endoscope holder for two handed endoscopic ear surgery are well highlighted.

The minimally invasive two handed endoscopic ear surgery (EES) allows better and panoramic view of the middle ear structures without much bone removal, no retroauricular incision and suturing. There is also no fatigue involved in long duration surgery as in single handed EES with the surgeon holding the endoscope in left hand.

Endoscopic cartilage tympanoplasty is operated by using the sliced tragal cartilage. Whereas for cholesteatoma surgery, the inside out technique of atticantroscopy is used with reconstruction of the attic defect.

Use of the endoholder requires the training to acquire the skills.

Electronic supplementary material

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Compliance with Ethical Standards

Conflict of interest

The authors declare that they have no conflict of interests.

Ethical Approval

All procedures performed in this study involved human participants and was in accordance with the ethical standards of the institutional committee and with the 1964 helsinski declaration and its later ammendments or comparable ethical standards. Institutional Ethics Committee has approved the study.

Informed Consent

Informed consent was obtained from all individual participants included in the study.