Surgical repair of bone defects of the ear canal wall with flexible hydroxylapatite sheets: a pilot study

Alloplastic bone cements in otologic surgery: Long-term follow-up and lessons learned

Objective

Otolaryngologists are often confronted with structural defects in the tegmen, scutum, or external auditory canal . Carbonated calcium phosphate (CCP) bone cements offer an alternative way of managing these defects.

Study Design and Setting

Retrospective review in an academic otology practice. The technical feasibility of these techniques described as well as the wound healing and structural integrity results.

Results

CCP bone cement was used to reconstruct defects of the tegmen or EAC in 22 patients. The material was used to repair the EAC in 19 of these patients, including complete EAC reconstruction in 4 patients, and tegmen defects only in 3 cases.

Conclusion

The surgical technique is not technically difficult and the alloplastic material is hard within minutes of application. Twenty patients have been followed for over 1 year with an average follow-up period of 3.8 years. Failure, defined as infection or explantation, occurred in 4 patients followed over 3 years. There was a difference in outcomes for pediatric cases. EBM rating: C-4

Reconstruction of lateral attic wall using autogenous mastoid cortical bone

PURPOSE

To explore the outcomes of lateral attic wall (LAW) reconstruction using autogenous mastoid cortical bone in cases with poorly developed zygomatic root cells and/or a low tegmen or with significant anterior or lateral sigmoid sinus in tympanomastoid surgery.

MATERIAL AND METHODS

Thirty-five ears with chronic suppurative otitis media, all of them either with poorly developed zygomatic root cells and/or a low tegmen (26/35 ears), or with significant anterior or lateral sigmoid sinus (9/35 ears), were included. LAWs were removed temporarily to offer exposure of the attic; after removal of the pathological conditions in the attic and the mastoid, LAW was reconstructed using autogenous mastoid cortical bone. The condition of the reconstructed LAW and tympanomastoid aeration was evaluated by computed tomographic scan or/and otoendoscopy.

RESULTS

The pathological conditions in the attic, the antrum, and the mastoid could be removed with safety in all cases; no serious complications occurred, the new canal appeared to be of normal size and shape, and no dislocation or necrosis of the repaired part was noted. Most of the cases had no significant attic retraction and kept good tympanomastoid aeration postoperatively.

CONCLUSION

The reconstruction of LAW is especially suited to the cases in our study, and the reconstructed LAW can produce an almost normal anatomical external auditory canal, prevent the formation of attic retraction, and restore the mastoid cavity aeration in most of the cases.

Surgery for tympanic membrane retraction pockets

BACKGROUND

Tympanic membrane retractions are commonly managed by ENT surgeons. There is currently no consensus as to the indications, timing and options for management of this condition.

OBJECTIVES

To study the effectiveness of different surgical options in the management of tympanic membrane retractions.

SEARCH STRATEGY

We searched the Cochrane Ear, Nose and Throat Disorders Group Trials Register; the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, 2010 Issue 1); PubMed (1950 to 2010); EMBASE (1974 to 2010); CINAHL (1982 to 2010); BIOSIS Previews; ISI Web of Science; CAB Abstracts; LILACS; KoreaMed; IndMed; PakMediNet; China National Knowledge Infrastructure; ISCTRN; UKCRN; ICTRP and Google. The date of the search was 17 March 2010.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of the surgical management of tympanic membrane retraction pockets in adults or children. Staging of the retraction using a known system must have been performed. Studies of cholesteatoma or perforations were excluded.

DATA COLLECTION AND ANALYSIS

Two authors independently collected and analysed data to minimise the effects of selection and reporting bias.

MAIN RESULTS

Two RCTs were included, involving 71 participants. The first study showed no statistically significant benefit of cartilage graft tympanoplasty over a watch and wait policy for either disease progression or hearing outcome. The second showed no additional benefit from the insertion of ventilation tubes over cartilage tympanoplasty alone with regards to hearing outcome.

AUTHORS' CONCLUSIONS

No evidence currently exists to either support or refute the role of surgery in the management of tympanic membrane retractions. Higher quality studies are much needed to ascertain this.

Reconstruction of outer attic wall defects using bone paté: long-term clinical and histological evaluation

The objective was to evaluate the long-term clinical outcome of the bony outer attic wall reconstruction (scutumplasty) by using autogenous bone paté in a series of patients who underwent canal wall up (CWU) mastoidectomy for middle ear cholesteatoma. In addition, an histological analysis of bone paté graft specimens taken during the second-look procedure 12 months after the first surgery, was carried out. A series of 134 ears from 128 patients with cholesteatoma who underwent staged CWU mastoidectomy and attic reconstruction with bone paté, between 1995 and 2000 inclusive, was retrospectively analyzed. In ten randomly selected ears, biopsies from the newly built outer attic wall were taken during the second-look operation and were microscopically analyzed. At the second stage operation, the bone paté graft was found normal in 64.9% of cases. In 39 (29.1%) patients there was a remarkable hypertrophy of the bone paté which was subsequently thinned out by using a diamond burr. A partial resorption of the bone paté was observed in 4.4% of ears and a total resorption in 1.4%. Residual cholesteatoma was found in 13.4% of ears. At the last follow-up visit, recurrent cholesteatoma was observed in 5.2% of ears. Self cleaning attic retraction pocket occurred in 4.4% of ears. Twelve months after implantation, histologic examination on the newly built bone showed a well-structured bony tissue. In particular, osteoblasts lined bone trabeculae with signs of an active tissue remodeling. In conclusion, the reconstruction of the outer attic wall should be considered a fundamental step when performing a CWU procedure in order to prevent attic retractions and recurrences of cholesteatoma. In our experience, autogenous bone paté graft has demonstrated good long-term results in outer attic wall reconstruction being adaptable, well tolerated, stable and of low cost.

Transmastoid Repair of Minor Skull Base Defects with Flexible Hydroxyapatite Sheets

This prospective open pilot study was designed to assess the suitability of flexible composite sheets of polymer and hydroxyapatite (HA) for the reconstruction of limited lateral skull base defects through a conservative transmastoid approach.Seven patients with a petrous bone dehiscence less than 3 cm in diameter, either iatrogenic or caused by chronic otitis media or temporal bone trauma, underwent a mastoidectomy. The defect was repaired with the new material and a connective tissue graft. All bone defects were detected by computed tomography (CT) of the temporal bone except one that was found at surgery in an asymptomatic patient.Outcome was evaluated in terms of anatomical integrity of the tegmina, absence of cerebrospinal fluid leaks, side effects, and extrusion and complication rates. None of the patients suffered from immediate side effects related to the implant or the operation. With a minimum follow-up of 18 months (maximum, 62 months), neither extrusion nor a foreign body reaction occurred. Postoperative CT confirmed a satisfactory anatomic contour. Although the number of patients is limited, these preliminary results are encouraging and indicate a need for further clinical trials with a material that allows a minimally invasive approach to selected skull base defects.

Tape-casting technique can prepare ?-TCP sheets with uniform thickness and flexibility

The objective of this study is to propose a new fabrication technology for bone substitutes. In this study, a tape-casting method was used to prepare flexible beta-tricalcium phosphate (beta-TCP) sheets. A beta-TCP slurry containing a binder and plasticizer was used in a doctor blade system. The beta-TCP sheet obtained by this tape-casting method was highly flexible, enabling twisting and free-form shaping. The beta-TCP sheet was approximately 0.21 mm thick. X-ray diffraction and Fourier transform infrared spectrometry revealed that the structure of the beta-TCP component in the sheet is the same as that of the original beta-TCP powder. Observation by field-emission scanning electron microscopy showed that the beta-TCP sheet had a flat, microgranular surface. During the early stages, the tensile stress-strain curves of the beta-TCP sheet showed a nonlinear behavior until reaching the point of final fracture. This result was derived from the ductile property of the prepared beta-TCP sheet. In conclusion, a flexible beta-TCP sheet was easily prepared using a tape-casting technique. Fabrication using tape casting offers the advantages of enabling the preparation of ceramic sheets with precise thickness and not requiring expensive fabrication facilities.