M. E. Wigand

Normal wound healing of the paranasal sinuses clinical and experimental investigations

SummaryTwenty-two patients underwent partial or complete ethmoidectomies and were subjected to standardized postoperative follow-ups including endoscopic photography of healing tissues. Sequential biopsies were also taken from the regenerating mucosa and compared with endoscopic findings. On this basis wound healing could be divided into four different phases, allowing for the diagnosis of healing disturbances and clinical planning of stage-dependent therapy. Additionally, a model of wound healing in the maxillary antrum of the rabbit was developed for better understanding the clinical observations. Regeneration of standardized mucosal defects was studied with three-dimensional histomorphological analysis. Circular wounds were found to regenerate concentrically, with wound closure starting by epithelial migration. Within 120 h, granulation tissue covering the wound surface started to become hyperplastic and bone apposition occurred with the formation of osteoid. The systemic application of prednisolone (2 mg/ kg per day i.m.) and topical 5% dexpanthenol ointment resulted in an acceleration of late epithelial wound closure together with a reduction in hyperplastic granulation tissue. Local applications of “epidermal growth factor” had no significant effect.

Endonasal Endoscopic Closure of Cerebrospinal Fluid Fistulas at the Anterior Cranial Base

This study reports our indications and limits for endonasal endoscopic closure of dural defects with a cerebrospinal fluid (CSF) leak at the anterior cranial base, and demonstrates our surgical technique. Fifty-three patients with CSF rhinorrhea were reassessed for the success rate of closure of the CSF leak. Surgery was successful in 98%, and 68% of fistulas were closed endoscopically. A free graft of autogenous mucoperiosteum of the inferior turbinate was the most frequently used tissue for defect closure. The endonasal endoscopic route proved relatively safe for the closure of dural tears, irrespective of the cause, up to about 10 × 10 mm. It is characterized by minimal morbidity because of the preservation of sinus ventilation and bony structures, supraorbital nerves, and olfactory fibers. Defects larger in size, predominantly of traumatic origin, were closed via the transfacial approach. The decision on the surgical approach was additionally based on the extent of the facial soft tissue injuries and the localization of the leak.

The enlarged middle cranial fossa approach for surgery of the temporal bone and of the cerebellopontine angle

SummaryDue to the fact that the temporal bone has broad segments of bone anterior to and behind the internal auditory canal which are empty of functionally important structures, a broad exposure of the cerebellopontine angle may be obtained from above. This technique is adequate for the management of acoustic neurinomas up to 3 cm in diameter. A low postoperative morbidity and a high percentage of hearing preservation with total tumor removal were obtained in a series of 190 cases. This report underlines the advantages of the procedure and points to various other indications.

Cranial Nerve and Hearing Function after Combined-Approach Surgery for Glomus Jugulare Tumors

In this retrospective study, oncologic and functional results of 46 patients treated for glomus jugulare tumor are reported. The standard surgical approach was the combined transmastoid-transcervical approach, modified according to the individual tumor growth, and eventually combined with a transtemporal or a suboccipital approach. Complete tumor removal resulted in a cure rate of 90%. New-onset cranial nerve palsies developed in less than 22% of patients. In 54% of cases it was possible to retain middle ear function. From a total of 12 patients with incomplete tumor removal and postoperative irradiation, progressive tumor growth was noted in 4 patients, and was controlled by salvage irradiation or surgery. Radical tumor removal by ablative surgery can be modified by efforts to reduce mutilating resections. In their place, individually tailored and combined multidirectional surgical approaches may allow total tumor removal with lower morbidity.

Advantages of the enlarged middle cranial fossa approach in acoustic neurinoma surgery

Utilizing an enlarged middle cranial fossa approach to the cerebello-pontine angle without destruction of the labyrinth or cochlea the authors have since 1981 operated on 263 unilateral acoustic neurinomas. Tumour sizes ranged between 3 mm intrameatal and 35 mm within the cerebello-pontine angle. Complete tumour removal was accomplished in 96%. There was one postoperative mortality, and only rarely neurological complications. Excellent function of the facial nerve was obtained in 78% (in small and medium sized neurinomas 90% House I and II) and severe paralysis persisted in only 6%. Preservation of hearing was possible in 70% of the small tumours, and in 50% of the total group. Against this background comparable data of the literature are reviewed, and the indications for the enlarged midfossa approach analyzed.

Experimental Sensorineural Hearing Loss Following Drill-induced Ossicular Chain Injury

In a guinea pig model, a standardized drill-induced injury to the body of the incus was applied, and the effects on hearing were characterized by electrocochleography. Drilling resulted in a threshold shift within seconds, and after 15 min it averaged 35.7 dB for clicks, 35 dB nHL for 4 kHz bursts, 36.7 dB nHL for 6 kHz bursts and 39 dB nHL for 8 kHz bursts. The deterioration of the threshold shift remained stable throughout the 5-week post-operative observation period. In five animals a disarticulation of the incudostapedial joint was performed prior to drilling, but this did not reduce the threshold shift. Caution is mandatory during drilling around an intact ossicular chain to avoid a permanent sensorineural hearing loss, and disarticulation of the incudostapedial joint prior to drilling has no protective value.

Selective Resection of the Semicircular Canals of Rabbits with Preservation of Hearing

The goal of this investigation was to develop a method of surgical removal of the semicircular canals of the rabbit without induction of auditory impairment. Four different surgical techniques were utilized: i) fenestration of the lateral semicircular canal; ii) fibrin glue perfusion of the canal following fenestration; iii) removal of the lateral semicircular canal by drilling after fenestration and fibrin glue perfusion, and iv) removal of all three canals after fenestration and fibrin gluing. Brainstem auditory potentials were recorded repeatedly for up to 3 months after operation and demonstrated preservation of hearing in all rabbits in the first group and in 78% of the second group. In the third group the potentials could be recorded in 67% of the animals and showed a 20 dB deterioration of hearing. After removal of all three semicircular canals residual hearing could be recorded in 50% of the rabbits. These animals regularly showed a 30-40 dB deterioration of hearing. A precise microsurgical technique using fibrin glue and bone chips for interruption of the peri- and endolymph flow proved crucial for hearing preservation.

Topographical Anatomy of the Internal Auditory Canal: Implications for Functional Surgery in the Cerebello-Pontine Angle

For exposure of the cerebello-pontine angle by an enlarged middle-fossa approach without destruction of the inner ear, bone removal anterior and posterior to the internal auditory meatus (c.a.i.) can be performed with orientation at landmarks. Based on the experience of more than 300 interventions and documented by a series of 10 temporal bone micro-dissections, rules have been established for reliable localization of the following structures: geniculate ganglion, Fallopian canal, vertical crest at the fundus of the c.a.i., basal coil of the cochlea, and ampulla of the superior semicircular canal. The surgical technique has enabled the authors to remove acoustic neurinomas of up to 3.5 cm with preservation of hearing in 51%.

Funktionserhaltende Chirurgie von Glomus-jugulare-Tumoren Ein realisierbares Ziel?

ZusammenfassungEine radikale Entfernung ausgedehnter Glomus-jugulare-Tumoren hinterläßt häufig schwere Einschränkungen durch Lähmungen der kaudalen Hirnnerven und die Obliteration des Mittelohrs. Die Operationsstrategie der Erlanger HNO-Klinik setzte sich zum Ziel, die postoperative Morbidität zu senken, und gleichzeitig die Sicherheit der Tumorkontrolle zu erreichen. Die vorliegende Untersuchung stellt die onkologischen und funktionellen Resultate retrospektiv an 24 Patienten mit Glomus-jugulare-Tumoren der Größen C und D dar. Der mittlere Nachbeobachtungszeitraum betrug 3,7 Jahre. Als Standardmethode der Operation diente der transmastoidale-transzervikale Zugangsweg, der je nach Wachstum des Tumors modifiziert und gegebenenfalls mit einer transtemporalen Freilegung des Felsenbeins oder mit Hilfe eines retrosigmoidalen Zugangs kombiniert wurde. Präoperativ wurde eine superselektive Embolisation, soweit möglich, ausgeführt. Eine Ergänzung mit postoperativer Strahlentherapie erfolgte in 7 Fällen. Eine Heilungsrate von 100% wurde nach vollständiger Entfernung des Tumors mit Hilfe eines multidirektionalen Vorgehens erzielt. Bei 38% dieser Patienten traten postoperativ neue Hirnnervenlähmungen auf. In 54% der Fälle konnten ein normal konturierter äußerer Gehörgang und das Mittelohr entweder erhalten oder rekonstruiert werden. Residualtumore mußten in 2 Fällen nach inkompletter Resektion und postoperativer Radiotherapie beobachtet werden. Die individuelle Anpassung des chirurgischen Vorgehens erlaubt eine funktionsschonende Therapie ausgedehnter Glomus-jugulare-Tumore. Die entsprechend der Tumorausbreitung gewählten Zugangswege und operativen Schritte gestatten vollständige Tumorresektion mit minimierter Morbidität.SummaryIn this retrospective study, oncologic and functional results of 24 patients treated for glomus jugulare tumor stages C and D are reported. The surgical approach used was a combined transmastoid-transcervical approach, which was modified according to individual tumor growth. As needed, this was combined with a transtemporal or retrosigmoid approach. Complete tumor removal resulted in a cure rate of 100%. Surgically induced cranial nerve palsies developed in 38% of the patients. In 54% of cases it was possible to retain middle ear function. Seven patients had incomplete tumor removal requiring postoperative irradiation, with tumor progression occurring in 2 patients. Radical tumor removal was modified by efforts to reduce mutilating resections. These results show that individually tailored and combined multidirectional surgical approaches can allow total tumor removal to be performed with lower morbidity.

Preservation of hearing in bilateral acoustic neurinomas by deliberate partial resection.

With the aim of preserving hearing, 20 acoustic neurinomas in 17 patients with neurofibromatosis 2 were intentionally submitted to an incomplete (80%) tumour removal. In 12 cases this was an operation on the last hearing ear with total deafness of the contralateral ear. If an auditus existed in both ears the better hearing ear was selected for the primary intervention. Early audiological controls evidenced residual hearing in 19 of the 20 cases operated on by the enlarged middle fossa approach, which was utilized inspite of the tumour diameters being between 1 and 6 cm in the cerebello-pontine angle. The oncologic and functional follow-up over 1 to 7 years showed different patterns of slow progression of hearing loss and of persistent auditory function over 2 to 7 years. Facial nerve function was excellent in 16 of the 18 controlled cases. Continued CT or MRT imaging revealed no signaling in 2 cases, constant tumour sizes in 10 cases and slow progression in 3 cases. With regard to the importance of an auditory communication in the younger adult, the described treatment modality appears to be the first choice method.