Pulsatile tinnitus as a rare presenting symptom of residual cholesteatoma.

Pulsatile tinnitus is an uncommon otological symptom, which often presents a diagnostic and management dilemma to the otolaryngologist. This symptom always deserves a thorough evaluation to avoid disastrous consequences from potentially life-threatening associated pathology. In most of the patients a treatable underlying aetiology can be identified. Frequent causes mentioned in the literature responsible for pulsatile tinnitus are benign intracranial hypertension syndrome, temporal bone paragangliomas and arteriovenous fistulae. Pulsatile tinnitus as a consequence of sigmoid sinus compression by a cholesteatoma has not been reported previously in the literature. Here a case of residual cholesteatoma with pulsatile tinnitus is presented, nine years after the first surgery.

[Preoperative imaging in chronic otitis surgery]. / Utilità della radiologia preoperatoria nella chirurgia dell'otite media cronica.

High resolution computed tomography (CT) is presently the most accurate technique to study the temporal bone. Nevertheless, there is no general agreement about its usefulness in pre-operative evaluation of chronic otitis media. Indeed, if we rule out some exceptions, CT is not fundamental for diagnosis which can often be obtained through an accurate otomicroscopy. The Otology Group in Piacenza applies the following absolute indications for pre-operative CT in chronic otitis media: 1) difficult otomicroscopy evaluation; 2) suspected petrous bone cholesteatoma; 3) dubious diagnosis; 4) suspect of malformations; 5) review of cases that had previously undergone mastoidectomy; 6) suspected intracranial complications and/or meningoencephalic herniation (in this case also a magnetic resonance imaging must be performed). With the exception of these specific conditions, pre-operative CT is useless in cases of simple chronic otitis. However, when a cholesteatoma is suspected, CT can provide the surgeon, particularly when inexperienced, useful, but not indispensable, informations. Pre-operative knowledge of these informations can allow a more accurate evaluation of the case, with a better planning of the surgical procedure, in order to ensure a more specific informed consent. Finally, the Authors point out the fact that surgeon must be able to interpret by his own the CT data to have a real advantage by this examination.

Electromyographic evaluation of facial nerve damage in acoustic neuroma surgery.

OBJECTIVE: This study aimed to determine whether postoperative facial nerve paralysis or surgical manipulation causing paralysis could be predicted on train responses during intraoperative facial nerve monitoring in acoustic neuroma surgery. STUDY DESIGN AND SETTING: This was a prospective study performed at a tertiary referral center. PATIENTS AND METHODS: Train responses were recorded on a floppy disk and compared with postoperative facial nerve function in 51 patients who underwent enlarged translabyrinthine acoustic neuroma surgery. MAIN OUTCOME MEASURES: The number, duration, frequency, and peak-to-peak amplitude of train responses were analyzed and compared with postoperative facial nerve function. RESULTS: Trains were observed in 42 of 51 patients. Six of seven patients with high-amplitude trains more than 250 microV, and three of five patients with bomber-type high-frequency trains elicited during tumor dissection from the facial nerve or stretching the nerve, showed severe facial nerve dysfunction. On the other hand, seven of the nine patients with no trains also showed severe facial nerve dysfunction. CONCLUSIONS: The presence of high-amplitude or high-frequency trains elicited by surgical manipulation to the facial nerve seems to indicate a critical situation for the facial nerve. However, certain types of mechanical trauma resulting in severe facial nerve paralysis cannot be identified by train responses.

Identification of internal acoustic canal in the middle cranial fossa approach: a safe technique.

BACKGROUND: The middle cranial fossa approach (MCFA) is a very valuable functional approach in the armamentarium of the neuro-otologic surgeon. Identification of the internal acoustic canal (IAC) in MCFA is one of the most tedious steps. Many techniques have been described to locate the IAC safely when using the MCFA. OBJECTIVE: We sought to describe a safe technique for identification of the IAC and to demonstrate its feasibility in temporal bone dissections, as well as to discuss our clinical experience with this technique. METHODS: The surgical anatomy of the 20 temporal bones were evaluated and measured, especially by defining the medial and lateral ends of the IAC and relations to the nearby located structures. Measurements were obtained at 3 levels: the width of the IAC at the level of the fundus, the width of the IAC at the level of the porus, and the safe distance around the IAC at the meatal level. The medial and lateral IAC end widths were compared with each other and with the safe area at the meatal level. RESULTS: The smallest, the largest, and the mean values were recorded. The mean width of the IAC at the level of the porus was found to be more than 3-fold that of the width of the IAC at the level of the Bill's bar, and the ratio between the width of the medial safe area around the IAC and the lateral end of the IAC was found to be more than 7-fold as wide. CONCLUSION: This technique offers direct quick exposure of the IAC, without handling the facial nerve and the inner ear structures. Forty-five cases of operations with the same technique showed excellent ease and safety of identifying the IAC medially in the MCFA.

[Enlarged translabyrinthine approach in large acoustic neurinomas]. / La via translabirintica allargata nei neurinomi dell'acustico di grandi dimensioni.

The translabyrinthine approach has long been, and in some centers is still, considered inadequate for the removal of large acoustic neuromas (AN). Over the years, with experience, the original technique has been modified, extending the approach to what is now called the enlarged translabyrinthine (ET) approach. Applying these modifications, between April 1987 and February 2000, the Gruppo Otologico in Piacenza, Italy removed 132 ANs, 3 cm or larger, from the cerebello-pontine angle. These tumors accounted for 25.9% of the 510 cases of AN to undergo surgery during that period. Of the 132 cases only one patient died and the percentage of complications was very low, generally lower than analogous series published in the literature. Such complications were progressively reduced in time, leading to a significant reduction in the length of post-operative hospitalization: on the average the 8.8 days were reduced to 5.7 in the last 43 cases. Ipsilateral preoperative hearing, inevitably sacrificed using the ET approach, was already significantly compromised in more than 65% of the cases. On the basis of the present data, it can be asserted that tumor diameter does not in any way preclude the use of the ET approach in AN surgery, rather the reduced morbility and shorter post-operative hospitalization make it the approach of choice for large ANs.

Meningiomas intrinsic to the geniculate ganglion.

Geniculate ganglion meningiomas are extremely rare lesions-only 14 cases have been reported in the literature. Two new cases of these tumors are described. On computed tomography and magnetic resonance imaging, both lesions appeared centered on the area of the geniculate ganglion, extending to the tympanic cleft and eroding the middle cranial fossa floor. The first case was treated through a middle cranial fossa approach. Because the tumor was so large in the second case, a subtotal petrosectomy was used. The authors review the literature to clarify the clinical and radiological characteristics of these tumors and their surgical treatment.

[Treatment of residual acoustic neurinomas]. / Il trattamento dei neurinomi dell'acustico residui.

Generally the main objective of acoustic neurinoma (AN) surgery is to totally remove the tumor associated with minimum morbidity. Nevertheless, in some cases residual tumor fragments are intentionally or accidentally left in place. These residues can lead to new growth. The present study provides a retrospective analysis of 14 cases of residual AN have undergone surgery at the Otology Group in Piacenza from 1987 to 1999. All these patients had previously undergone at least one retrosigmoidal exeresis although only one had been performed at the Otology Group. All patients except 1 were affected by anacusia at the time of surgery. The list of post-operative deficits included 2 hemipareses, 3 irreversible facial paralysis with consequent corneal opacity in 2 cases, 1 dysmetria and 1 paralysis of the abducent nerve. The patients had also undergone the following additional treatments: 1 emergency revision to drain a cerebellar hematoma, 3 ventricle-peritoneal derivations, 1 double application of stereotactic radiotherapy and 2 surgical procedures for facial plasty. Ten cases underwent the revision surgery at the Otologic Group using a translabyrinthine approach and 4 using a transcochlear approach. Tumor removal was deemed complete in all cases. The sole post-operative complications were a subcutaneous hematoma at the point where abdominal fat was removed and a temporary paralysis of the abducent nerve. Post-operative hospitalization was an average of 6.9 days. Analysis of the results showed that AN must be operated at selected centers in order to reduce the post-operative neurological deficit and the percentage of residual tumor. It also indicated that the retrosigmoid approach has a higher risk of accidentally leaving tumor residues than the other approaches. Finally, in the presence of a residual AN, the translabyrinthine approach offers the greatest advantages.

Fast-growing vestibular schwannoma.

A case of a Jehovah's witness affected by an intracanalicular vestibular schwannoma with an extremely fast growth rate is presented. Nine months after presentation, the tumor reached 23 mm in the cerebellopontine angle. A partial removal through a retrosigmoid approach was planned. Because of the presence of a dominant high jugular bulb masquering the internal auditory canal, the intracanalicular portion of the tumor was left in place. The residual tumor grew 12 mm in 2 months. Even after a gross total removal through a middle cranial fossa approach, the tumor recurred, reaching the size of 30 mm in 17 months. A modified transcochlear approach was then performed, and the patient was free of disease at the last radiologic follow-up, 8 months after the surgery. We illustrate our strategy in treating this aggressive benign lesion with unusual behavior.

No cerebrospinal fluid leaks in translabyrinthine vestibular schwannoma removal: reappraisal of 200 consecutive patients.

OBJECTIVE: The objective of this study was to validate measures taken to reduce the number of cerebrospinal fluid (CSF) leaks after removal of vestibular schwannomas to 0. STUDY DESIGN: This study was a retrospective case review. SETTING: The study was conducted at an otology/neurotology tertiary referral center (Gruppo Otologico, Piacenza, Italy). PATIENTS: Three hundred thirty-one vestibular schwannoma patients were studied. INTERVENTIONS: The enlarged translabyrinthine approach (TLA) was used in all cases, with a number of modifications in the last 200 patients. It was extended in 22 patients with blind sac closure of the external meatus, removal of the posterior bony canal wall, and obliteration of the Eustachian tube and middle ear. MAIN OUTCOME MEASURES: Whether patients had a leak through the wound, the nose (rhinoliquorrhea), or the ear (otoliquorrhea) was assessed. RESULTS: In an early group, the percentage of CSF leaks was 6.9%. On the basis of the evaluated causes, as time went by, technical modifications evolved. They consisted of 1) the total conservation of the fascioperiosteal flap, 2) obliteration of all petrosal cells possibly communicating with the middle ear, 3) removing the incus in a correct way, 4) closing the attic with periosteum, 5) obliterating the surgical cavity, leaving strips of abdominal fat with their medial ends inside the cerebellopontine angle, 6) suturing the musculo-periosteal layer in a correct way, and 7) fixing the skin flap to the underlying surface. The application of these modifications resulted in a total absence of CSF leaks in 200 consecutive patients thereafter. Also, no cases of meningitis were encountered. CONCLUSIONS: To our knowledge, this is the first series of 200 consecutive vestibular schwannoma patients operated by means of the enlarged TLA without a single CSF leak. When the appropriate measures are taken, the number of CSF leaks after removing tumors through the enlarged TLA must and can be reduced to 0.

[Facial nerve identification in the translabyrinthine approach: an alternative method]. / Identificazione del nervo facciale nella via translabirintica: un metodo alternativo.

Since the abrupt drop in the mortality rate as a result of the introduction of microsurgical dissection techniques in the treatment of acoustic neuromas, surgeons have concentrated their efforts on preserving hearing and facial nerve function. In the translabyrinthine approach, identification of the facial nerve at the fundus of the internal auditory canal is an important step for subsequent dissection. However, the identification techniques available to date carry with them some potential risk of facial nerve injury when performed by inexperienced surgeons. In addition, they are time-consuming procedures. The authors present an alternative method for identification of the facial nerve at the fundus of the internal auditory canal during the translabyrinthine approach. The superior ampullary nerve is interrupted at the superior cribrosa area where it is not in intimate relationship with the facial nerve. Medial reflection of the superior ampullary nerve and the superior vestibular nerve facilitates identification of the facial nerve and preparation of a vestibulo-facial dissection plane.

Complications and their management in tympanomastoid surgery.

Chronic diseases of the ear and their surgical treatment can endanger the delicate structures of the temporal bone in close relationship with the middle ear. The experience and expertise of the otologic surgeon, based on perfect knowledge of the complex anatomy of the whole temporal bone, are unfortunately built up partly through the management of complications encountered in tympanomastoid surgery and may require knowledge of basic neuro-otologic procedures. Paralysis and paresis of the facial nerve and labyrinthine, and dural and vascular injuries may have consequences not only in the final result of surgery but also in endangering the patient's life. All major complications are discussed and some possible treatments are proposed. Minor complications affecting the temporomandibular joint, the dura, the external auditory canal, and the bony canal wall are also covered, along with some suggestions on how to keep these consequences within reasonable percentages.

Infratemporal fossa approaches to the lateral skull base.

The infra-temporal fossa approach is one of the lateral approaches to the skull base. It is indicated for the treatment of tumors such as glomus tumor, petrous apex cholesteatoma, chondroma, lower cranial nerve neuroma and nasopharyngeal cancer. In the present paper, we described the surgical anatomy of the lateral skull base and the indications for the infra-temporal fossa approach with its variants. We showed the hints and pitfalls in the procedures. Five illustrative cases are also presented.

[Cerebrospinal fluid leak after translabyrinthine approach in acoustic neuroma excision]. / La liquorrea come complicanza della via translabirintica nel trattamento del neurinoma dell'acustico.

Cerebrospinal fluid (CSF) leak is one of the most dangerous complications that can arise in cases of acoustic neuroma removal. It increases the risk of meningitis, requires longer postoperative recovery and often requires revision surgery. A retrospective analysis was performed on all cases of acoustic neuromas which had undergone translabyrinthine surgery at the Gruppo Otologico, Piacenza, Italy, between April 1987 and December 1997, in the aim of finding the causes of postoperative CSF leaks. The causes found were high pneumatization of the temporal bone and improper execution of some surgical steps. The technique has presently been modified on the basis of the experience gained from cases of CSF leaks. By scrupulously applying these modifications, from July 1994 to December 1997, a total of 160 patients were consecutively treated using the translabyrinthine approach without a single case of postoperative CSF leak. Routine use of this modified technique can and must lower the percentage of CSF leaks after a translabyrinthine surgery to nearly 0%.

Anatomic relationships between surgical landmarks in type b and type c infratemporal fossa approaches.

Anatomic relationships of the structures exposed in type B and C infratemporal fossa approaches were studied in 20 temporal bones. The intrapetrous carotid artery (ICA), cochlea (CH), eustachian tube (ET), foramen spinosum (FS), foramen ovale (FO) and anterior foramen lacerum (AFL) were exposed by drilling of the glenoid fossa and base of middle cranial fossa. The relationships of the ICA with the cochleariform process (CP), CH, ET, FS, FO and AFL were noted along with associated measurements. The CP was lodged at a mean distance of 9.2 mm from the ICA genu. The ET was found to intersect the ICA. The mean distance of the ICA to the CH was 1.6 mm. The carotid canal was dehiscent on its horizontal portion in 30% of the bones studied and on its vertical portion in 5%. The periarterial venous plexus was found in 70% of the bones. No obvious branch was observed emerging from the vertical portion of the ICA. The FS was found to be a canal having a mean length of 5.8 mm.

Myringoplasty in children: factors influencing surgical outcome.

Age, size, and site of perforation, condition of the ear, status of the contralateral ear, grafting materials, and more are considered factors influencing the success rates in myringoplasties in children. The ambivalence in results is mainly due to nonhomogeneous patient groups. In an effort to compose groups as homogeneous as possible for analysis of influencing factors, a retrospective study of 51 pediatric myringoplasty cases (51 ears) was undertaken. All patients had perforations caused by simple chronic otitis media. The overall surgical success rate was 82.3% at 18 months, and for young (5 to 10 years) and older (11 to 16 years) children it was 77.2% and 86.2%, respectively. Anterior, central, and total perforations healed without significant differences. Outcome in unilateral perforations was better than bilateral: 96.9% and 55%, respectively (p < 0.01). Discharging ears (100%) healed better compared with dry ears (75%) (p < 0.05). Analysis of the literature also revealed significant difference in success rates of discharging and dry ears: 92.5% and 80.6%, respectively (p < 0.01). We conclude that, contrary to comments in the literature, discharging ears in children favor good outcome and they should be operated on regardless of age and site of perforation. However, in bilateral perforations results may not be so rewarding.

The cochlear aqueduct: an important landmark in lateral skull base surgery.

The cochlear aqueduct (CA) is used as a landmark in lateral skull base surgery. In this study anatomic relationships between the CA and adjacent neurovascular structures were examined by dissecting 32 temporal bones. Observations of the relationship of the external opening (EO) of the CA with the ninth, tenth, and eleventh cranial nerves, inferior petrosal sinus (IPS), and intrapetrous carotid artery (ICA) were noted. In addition to the distance of the EO of the CA to the vertical portion of the ICA, the entire length of the CA and the width of the EO were also measured. The ninth nerve was the only structure lodged at the EO of the CA in 34.4% of bones. However, in 40.6% of bones only the IPS crossed the EO of the CA, although the ninth nerve was situated just anteroinferiorly in the vicinity of the EO. In 15.6% of bones it was possible to observe both the ninth nerve and the IPS crossing the EO. In 9.4% of bones the EO of the CA was found to be occupied by the tenth and eleventh nerves. It was also observed that the ICA was located anteriorly on the same sagittal plane with the EO in 15.6% of bones. It was concluded that although in 90% of cases the EO of the CA was in close relation with the ninth nerve, other structures such as the IPS, the tenth and eleventh cranial nerves, and the ICA were also at risk during drilling in this area because of their intimate relationships with the EO of the CA.