Fish or n3-PUFA intake and body composition: a systematic review and meta-analysis

Obesity is a major public health issue and an important contributor to the global burden of chronic disease and disability. Studies indicate that fish and omega-3 polyunsaturated fatty acids (n3-PUFA) supplements may help prevent cardiovascular and metabolic diseases. However, the effect of fish oil on body composition is still uncertain, so we performed a systematic review of randomized controlled trials and the first meta-analysis on the association between fish or fish oil intake and body composition measures. We found evidence that participants taking fish or fish oil lost 0.59 kg more body weight than controls (95% confidence interval [CI]: -0.96 to -0.21). Treatment groups lost 0.24 kg m(-2) (body mass index) more than controls (-0.40 to -0.08), and 0.49 % more body fat than controls (-0.97 to -0.01). Fish or fish oil reduced waist circumference by 0.81 cm (-1.34 to -0.28) compared with control. There was no difference for fat mass and lean body mass. Further research is needed to confirm or refute our findings and to reveal possible mechanisms by which n3-PUFAs might reduce weight.

[Invasive cholesteatoma of the old radical mastoidectomy]

OBJECTIVE

The aim of this study is to show the importance of computed tomography scanning (CT) and magnetic resonance imaging (MRI) in ancient radical cavities and to determinate the risk factors of an invasive cholesteatoma recurrency.

MATERIAL AND METHOD

We present 4 cases of medial invasion in the petrous bone of a cholesteatoma without specific symptomatology which appeared many years after undergoing radical mastoidectomy for an acquired cholesteatoma.

CONCLUSION

The analysis of this series allowed to put in evidence the factors of suspicion of an underlying cholesteatoma. They are: the age, an aural discharge, numerous surgical interventions, immunodeficiency, cholesteatoma in childhood and antecedent of facial nerve palsy. This trial emphasizes the importance of imaging (CT and MRI) in front of an ancient radical cavity which presents one or some of these factors in order to eliminate a recurrence of an invasive cholesteatoma. Let us note that the demand of the patients is sometimes aesthetic or functional.

[Congenital cholesteatoma of the ear in the child. Clinical, follow-up and therapeutic analysis of a series of 34 cases]

Long a subject of debate, congenital cholesteatomas of the middle ear appear to be a specific clinical entity different from the much more frequent classical acquired cholesteoma. Characteristic features of congenital cholesteatomas are young age at diagnosis, typical peroperative presentation, satisfactory mastoid air cells in almost all cases, and associated congenital malformations, which may involve the otology system or not. Diagnosis is a difficult task due to the long latency period with no clinical manifestations. These congenital cholesteatomas appear to be more aggressive in a mastoid with functioning air cells. Thus open excision does not appear to be appropriate and should be reserved for selected cases. For us, the closed technique with two procedures is more adapted but requires good cooperation with the family. The risk of recurrence is however significant and at least comparable to that of acquired cholesteatomas in children. Follow-up should be persuade as long as possible. Functional results have been encouraging even though ossicular destruction is frequent. The quality of the auditory tube appears to be a determining factor.

[Cholesteatoma of the middle ear in children. Clinical, developing and therapeutic study in a series of 215 consecutive cases]

A retrospective study of 215 cases of cholesteatoma in 199 children operated on from 1985 to 1996 was conducted. Mean age of the children was 9.6 years. Bilateral cholesteatoma was present in 32 cases (8%). The cause was congenital in 32 cases (16%), iatrogenic in 24 cases (11%) and secondary or acquired in 63%. The surgical procedure was a closed technique in 88%, an open technique with or without ossiculoplasty in 10%, and exclusion of the ear using the Rambo technique in exceptional cases (1%). The facial nerve was exposed in 17%. A labyrinth fistula was discovered in 4%, and an intracranial suppuration in only 0.5%. A secondary open procedure was required in 5 cases (2.5%) and secondary exclusion 3 times (1.5%). The ossicular chain was interrupted in 24.2% of the cases and ossicular rehabilitation was performed in 68% of the cases (39% type II, 29% type III), including 49% during the first procedure. At least 2 operations were needed in 62% of the children and 21% had 3 operations. Residual cholesteatomas were observed in 21.5% of all children in the series, 33% in those with a second operation. Recurrence rate was 10%. Mean hearing loss was 28 dB for a mean gain of 4 dB. Post-operative hearing capacity was socially useful in 64% of the cases, including 12% who had normal hearing. Labyrinthization was observed in 15 cases, including 4 cases with total hearing loss. These result are in general agreement with data in the literature. Our strategy is based on a closed procedure for cholesteatomy and systematic re-evaluation at 1 year. The open technique is useful for very extensive lesion on a narrow mastoid, either as second intention procedure or more rarely as a first intention procedure. Management in children differs from that in adults since in adults the destruction has usually progressed further in a mastoid which accepts an open procedure more readily.

Concerning the Late Diagnosis of Certain Cerebellopontine Angle Tumors

The sensitivity of diagnostic methods for cerebellopontine angle lesions (auditory nerve electrophysiology, computed tomography scanning, magnetic resonance imaging) has increased in recent years. Paradoxically, in our experience this has not led to an increased percentage of tumors detected at an early stage. In 1975 20% of tumors were confined to the internal auditory canal, whereas only 6.6% were intercanalicular in 1988. A detailed analysis of 120 recent cases included first symptoms, time between first symptoms and diagnosis, symptoms at diagnosis, and size of tumor. We conclude the low percentage of intracanalicular tumors in the recent series results from: (1) rapid growth in some cases; (2) slow enlargement of the tumor over a long time without compression of adjacent cranial nerves leading to a paucity of symptoms; (3) misleading clinical pictures, including sudden hearing loss and hydrops; and (4) tumor symptoms masked by unrelated pathologic processes (otosclerosis, presbyacusis, trauma).

Laser micromanipulation in the mouse embryo: a novel approach to zona drilling

OBJECTIVE

To introduce the use of excimer lasers for penetration of the zona pellucida for micromanipulation purposes.

DESIGN

Cryopreserved two-cell mouse embryos were thawed and exposed to the 248-nm line of a krypton fluoride excimer laser (Lambda Physik EMG 202, Goettingen, Germany) creating a 2 to 4-micron opening in the zona pellucida.

SETTING

The Laser Ablation Laboratory at DuPont and the in Vitro Fertilization Laboratory at The Medical Center.

INTERVENTIONS

The embryos were exposed in either phosphate-buffered solution (PBS) or modified human tubal fluid (HTF) with the laser power varying from 1 to 2 J/cm2 and cultured in Ham's F-10 medium (GIBCO, Grand Island, NY) with 0.4% bovine serum albumin.

MAIN OUTCOME MEASURES

The outcome of each experiment was measured by blastocyst formation of laser-exposed embryos as compared with a set of unexposed control embryos handled in a similar fashion.

RESULTS

Successful laser penetration of the zona pellucida was achieved using the 248-nm line of a krypton fluoride excimer laser. A higher blastocyst formation was found for embryos exposed in PBS. The higher optical absorption of the modified HTF partially inhibited embryo development. The blastocyst statistics increased 2.5-fold times by reducing the exposure of the embryos to ablation by-products.

CONCLUSIONS

The use of a krypton fluoride excimer laser was introduced as a new method to open the zona pellucida of two-cell mouse embryos without interrupting blastocyst formation.

Problems in alloplastic middle ear reconstruction

Alloplastic materials have been used in middle ear reconstruction since 1952. Biologically, biomaterials and specifically ceramics can be defined as being bioinert, bioactive or biodegradable; these terms being descriptive of the biochemical response provoked by the material in the host tissue. Various ceramics, carbons and polymers and their reactions have been studied by the author and his colleagues over the past 5 years utilising animal implantation and fibroblast culture studies aligned with experience from clinical usage. The qualities of the ideal alloplastic implant namely: biocompatibility, stabilisation and incorporation, the consistency of the implant and bioactive bonding and the biofunctionality or mechanics, are applied to the materials currently available. No single alloplastic material fulfills all criteria, the problems encountered in relation to the biomaterials are reported. A better understanding of the microstresses, fatigue and microfractures is necessary, before the ideal alloplastic biomaterial becomes available.

[Apropos of the infratemporal pre-auricular approach (its value in the approach to the midline skull base]

The role of the infratemporal pre-auricular pathway to the median base of the skull resides in the fact that it enables very wide access to this region while sparing the facial and auditory nerves. Among the operations performed on the approaches of the base of the skull by their teams, the authors chose a particularly typical observation dealing with the indication of this pathway: a 34-year old male with a giant cholesteatoma of the tip of the petrous bone totally surrounding the internal carotid artery along its entire (intrapetrous) length, from the cervical region to the cavernous sinus, having invaded the clivus and pushed back the brainstem. This lesion is located on the side of the only healthy ear. The patient is completely deaf in the ear on the other side. The operation enabled its complete exeresis while respecting the facial, auditive and vestibular functions.

[Congenital cholesteatoma of the middle ear and mastoid. Apropos of 5 cases]

Five cases of congenital cholesteatoma of the middle ear and mastoid as defined by Derlacki's criteria were encountered over a 14 month period. They make up 5% of all cases of cholesteatoma managed over the same period of time. Three were young children and all presented with unilateral hearing loss. One had associated multiple congenital abnormalities of the external and middle ear. Only in one patient was the diagnosis made on initial otoscopic examination and the remainder diagnosed on CTscan, myringotomy and tympanotomy. All were operated on; three by the intact canal wall technique, one by the canal down technique with mastoid cavity obliteration and one by atticotomy with lateral attic wall reconstruction. One patient required a second stage operation for excision of an extension of disease deep to the superior semicircular canal via the middle cranial fossa approach in order to preserve cochlear function. These five cases illustrate the diagnostic pitfalls of this condition in which silent danger lurks behind an intact tympanic membrane.

Results of middle ear reconstruction surgery

Reconstructive surgery of the middle ear comprises two types of operations, i.e. reconstruction of the surroundings of the middle ear (external auditory canal) and reconstruction of the tympano ossicular contents of the middle ear (tympano-ossiculoplasty). Reconstruction of the external auditory canal may be total after certain open techniques, or partial after certain closed techniques. The results are markedly better when cortical bone autografts are used rather than materials such as Ceravital or Hydroxylapatite. Furthermore, cavity obliteration gives excellent results in 90% of cases (using bone powder, biomaterial powder, fibrin glue and covering muscular flaps). Tympano-ossiculoplasty gives on the whole, good results. Based on statistics of over 2200 cases, the author dwells in particular on the use of ossicular homografts, the results of which are generally superior to those of the best biomaterial (Ceravital and Hydroxylapatite).

The prognostic value of the stapedius reflex in peripheral facial palsy

Stapedius reflex can provide useful prognostic information in FPs when the middle ear is normal. Its preservation may have a favorable significance in partial FP and Bell's palsy. Its loss, even though less reliable, can also have some value as an indicator for a poor prognosis in patients with total and herpes zoster FPs. Most importantly, our findings have shown that the SR alone is not sufficient to be of prognostic value, but is useful if combined with other clinical parameters and electrical responses.

[Synergism between noise and ototoxic drugs: new experimental data]

Results of experiments investigating, in the guinea pig, the effects of combinations of gentamicin (GM), ethacrynic acid (EA) and acoustic stimulations are reported. They indicate that functional and morphological alterations develop only after GM has penetrated specifically into the sensory cells, that this penetration is indirectly facilitated by EA, since it is known to increase GM concentration in endolymph, and directly by functional depolarization of the cell, as it occurs during normal acoustic stimulation.

Modern diagnostic strategy for acoustic neuromas

We have reviewed the most recent 120 cases of acoustic neuromas operated upon in Bordeaux, France. In so doing, we have defined the strategy required to reach an accurate diagnosis as essentially comprising three stages. The first of these is to understand that the presenting symptom complex may be typical with progressive unilateral hearing loss, tinnitus, etc., or atypical with sudden hearing loss (10%), recovering facial paralysis (3.3%) or a Menière's syndrome (3.3%). Included in the first stage of diagnosis are audiovestibular investigations. An absent stapedial reflex was noted in 41% of our cases and an abnormality in vestibular testing in 95% of cases tested. These findings would be clear indicators to proceed to the second stage of the diagnostic strategy. This second stage comprises electric response audiometry consisting of auditory brainstem response (ABR) testing and electrocochleography (ECochG) employed as a filter for determining which patients should proceed to the third stage of testing. A combination of ABR and ECochG provides the clinician with results of high sensitivity and specificity. The false-negative rate for combined results in our experience has been less than 1%. The final diagnostic stage is radiological imaging, in particular using magnetic resonance imaging (MRI) with gadolinium contrast as the modality of choice. MRI is superior to CAT scanning, especially in the diagnosis of stage I intracanalicular tumors.

Aesthetic surgery for microtia

We describe here a technique for reconstruction of the external ear based upon an autogenous costal cartilage graft which is inserted into a cutaneous pocket dissected in the auricular area. Three subsequent procedures are then performed: rotation of the ear-lobe; reconstruction of the tragus; and elevation of the auricle. The ideal age for reconstruction is about 7 years. This technique was originally described by Brent, who has a very extensive experience with this kind of surgery. Skin deficiencies can be overcome by using either a temporo-parietal fascial flap or a skin expander.

[Cochlear and facial nerve function after surgery of acoustic neuroma]

Oto-neuro-surgical teams of Bordeaux University Hospital operated at this day, 700 acoustic neuroma. A retrospective study of the 120 last cases has shown the facial function be abnormal clinically in 16% of cases and in 50% from the electrophysiological point of view. Immediately after surgery: 39% have normal function (grade I), 22% have partial palsy (grades II, III, IV), 39% have total palsy. With 3 months follow up these percentages improve to become respectively 53%, 34% and 13%. For the cochlear function, 28 patients had good hearing before surgery (average pure tone threshold less than or equal to 35 dB and speech discrimination score greater than or equal to 70%). Results depend on the size of the tumour and on the difficulty of dissection during surgery. The hearing could be preserved at a good level in 8 patients (28.5%).

Techniques of tympanomastoidectomy

The authors describe the various techniques of tympanomastoidectomy that can be used to eradicate chronic disease processes. The techniques are either open or closed operations; the factors in determining the choice of technique for specific conditions are presented.

Limits of ABR and contribution of transtympanic electrocochleography in the assessment of cerebellopontine angle tumours

Auditory brainstem responses (ABR) and transtympanic electrocochleography (ECochG) were analysed for 63 patients with tumours of the cerebellopontine angle (CPA) and/or internal auditory meatus (IAM). ABR recordings indicated a clearly prolonged wave I-V interval (above 4.3 ms) in half of the patients, hence suggesting a retrocochlear disorder. For the remaining patients ABR alone was not sufficient for clear diagnosis and ECochG was therefore used in addition. When the latency of wave V was uncertain due to the absence of wave I, the latency of wave N1 was always measurable by ECochG. The NI-V interval evaluated in this way was always significantly prolonged (above 4.5 ms) relative to a control group of patients with a sensorineural hearing loss. In 9 of the 13 subjects without any discernible ABR, an ECochG response could be recorded and its threshold was often better than the mean pure tone audiogram. This study confirms the validity of transtympanic ECochG in the diagnosis of retrocochlear disorders. The time difference observed between wave N1 (ECochG) and wave I (ABR) in CPA tumours is discussed and a possible explanation is proposed.

Electrophysiological prognosis in facial paralysis

Electrical prognosis was evaluated in 79 patients with facial paralysis, of spontaneous (n = 43) or post-traumatic origin (n = 36). Three electrophysiological tests were employed jointly: detection, stimulation and stimulodetection. The patients were reviewed at least 1 year later, in order to appreciate the agreement between the electrical prognosis and the clinical outcome (satisfactory or not). Those patients with a favourable prognosis on electrical testing had in the majority of cases a satisfactory outcome. The accuracy of the prognosis was also better in cases of early examination (within 15 days) and partial paralysis.

The Portmann procedure after sixty years

This article recalls the technique described by Georges Portmann in 1926 for the opening of the endolymphatic sac in cases of Meniere's disease. Criteria of indication used at the time are critically analyzed. Modifications of the original operation proposed by various authors, particularly those of T. Naito, W. House, A.W. Morrison, and I.K. Arenberg, are then described. Finally, the current technique and indication criteria implemented in Bordeaux are analyzed, with stress on electrocochleographic determination of the summation potential and its disappearance under the effect of glycerol. According to the author, these latest examination techniques contribute to improving results by providing a better selection of cases likely to be treated by the opening of the endolymphatic sac.

Stapedius reflex and cerebellopontine angle tumours

The stapedius reflex was investigated in 61 patients with cerebellopontine angle tumours, in order to evaluate the reliability of the reflex-decay test in VIIIth nerve disorders. The reflex was completely normal in 11% of the patients. The 2 most frequently observed abnormalities were (1) an absence of the reflex when stimulating the ear on the side of the tumour, and (2) the conjunction of pathological reflex-decay at 0.5 kHz with a unilateral threshold elevation and/or absence of the reflex at other frequencies. The decay test was normal in one-third of the patients with a preserved reflex.

Ceravital in ossiculoplasty: experimental studies and early clinical results

The biocompatibility of the bioactive glass-ceramic Ceravital was investigated experimentally both in vivo and in vitro. In the former, ceramic discs were interposed in 30 rat middle ears for periods ranging from 6 weeks to 12 months. In the latter, Ceravital otological prosthesis were placed in human fibroblast culture. Reactions to the biomaterial were assessed by means of scanning electron microscopy (SEM) with chemical analysis facilities (EDAX, WDAX) and light microscopy. The interface reactions were similar in both in vivo and in vitro studies and confirmed the findings of other authors regarding the implants' biocompatibility and bioactivity. The technique of ion etching, however, enabled clear demonstration of this bioactivity on the implant surface, exposed merely to the middle-ear secretions, thus questioning the necessity of placing bone pâté on the implant head at surgery, in order to encourage bioactive bonding with the overlying drum. A clinical trial of Ceravital in 128 patients with an average follow-up period of 2 years is reported. Forty per cent of these patients underwent a type II tympanoplasty, 60 per cent a type III. Though relatively short-term, the results to date have been encouraging: 88 per cent of the implants have been well-tolerated; 70 per cent of the cases have yielded a satisfactory hearing result; and only 3 per cent of the implanted prostheses have been extruded.

Summating potential and water balance in Meniere's disease

The summating potentials (SP) to free-field 1-, 2-, 4-, and 8-kHz, 90-dB HL tone bursts were recorded by means of transtympanic electrocochleography in 45 patients divided into three groups: those with Meniere's disease, those whose diagnosis was uncertain, and control subjects. The similarities across frequencies between the human SP (promontory) and the experimental SP (DIF component from basal turn) suggest that the SP recorded in electrocochleography originates mostly from the base of the cochlea; negative values were observed at low frequencies (1 to 2 kHz), positive values at high frequencies (8 kHz). Patients with Meniere's disease showed significantly larger SP values than control subjects. The effect of orally administered glycerol on the SP and action potential amplitudes was evaluated by means of automated recordings repeated every 5 minutes. Summating potential values were remarkably constant in the control group. A decrease in SP absolute amplitude was observed in most patients with Meniere's disease and some subjects with uncertain diagnoses, specifically at low frequencies. These changes were frequently associated with action potential amplitude and auditory threshold improvements at low frequencies. It is assumed that the glycerol-induced SP changes at low frequencies are related to modifications in the low frequency mechanical response of the basilar membrane at the basal turn.

Experimental and clinical aspects of carbon as a middle ear prosthesis

The biocompatibility of vitreous carbon and carbon fibre reinforced carbon (CFRC) as middle ear implants was investigated. In separate animal model systems, vitreous carbon was implanted in the middle ear of 20 DA rats for up to 6 months, whilst 3 varieties of CFRC (basic or crude, ultrasonically cleaned, glazed) were implanted in 98 guinea-pig middle ears for up to 4 months. Tissue reactions to implantation were assessed by means of stereoscopic and standard light microscopy, and scanning electron microscopy with chemical analysis facilities (EDAX, WDAX). Vitreous carbon and glazed CFRC were considered suitable for human implantation and a trial of the latter was started in 23 patients (14 partial, 9 total ossicular implants). At 9 months, only 52% of the implants were still in situ; 40% had been extruded and 8% had elicited inflammatory responses which would undoubtedly result in extrusion. Carbon particle dissemination with carbon fibre destruction and exposure as a result of peroperative prosthesis drilling were considered the likely causes for the failure of this implant.

Extracochlear implants

A unichannel extracochlear implant designed and made in our laboratory was tried on several patients. Results to date are very similar in all cases. Very rudimentary auditory information is provided, which can help totally deaf patients.