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Jona Kronenberg

Publications and source records attributed to Jona Kronenberg.

At least 37 records · Page 2Linked to original sources
PubMed2005

Radiology of the cochlear aqueduct.

OBJECTIVES: We sought to determine normative data for the radiologic presentation of the cochlear aqueduct (CA), hypothesizing that increasing the scanner's resolution could enhance detection capability. METHODS: Axial sections of 502 high-resolution computed tomography (CT) images of temporal bones (488 patients) were reviewed. A type 1 CA was visualized on CT scans up to the vestibule, and its portion in the otic capsule segment could be seen as a thin (<1 mm) streak. In type 2, we were able to detect the medial two thirds of the structure, but we failed to see the whole otic capsule portion. In type 3, only the external aperture of the aqueduct and/or the medial third was seen. We defined undetectable CAs as type 4. RESULTS: We obtained CT scans with 0.6-, 1.1-, or 1.3-mm-thick slices through the petrous bones in 9.5%, 58.8%, and 31.7% of cases, respectively. The CA was visible and bilaterally symmetric in 49% of the images, and type 2 was the most commonly detected CA type (36%). The CA was invisible on either side in 21.9% of scans, irrespective of CT resolution, and was asymmetric in 53 of the 502 images. The CA types varied with changes in resolution, although type 3 appeared unchanged independent of alterations in resolution in most cases. CONCLUSIONS: There was no significant difference in CT detection capability between CA types at different resolutions. Computed tomography failed to demonstrate any CAs > or =1 mm in width in the otic capsule segment.

Adolescent↗
PubMed2005

Electrical stimulation levels and electrode impedance values in children using the Med-El Combi 40+ cochlear implant: a one year follow-up.

The present study was designed to follow changes in electrical stimulation levels and electrode impedance values (EIV) in children using the Med-El Combi 40+ cochlear implant (CI) during the first 12 months of implant use. The maps of 24 prelingually deaf children implanted at a mean age of 5.9 years (range 1-15.9 years) using the TEMPO+ speech processor programmed with CIS+ strategy were examined at five time points: initial stimulation, and 1, 3, 6, and 12 months post-initial stimulation. Most comfortable levels (M) and electrode impedance values (EIV) were analyzed according to three cochlear segments: apical, medial, and basal. Results indicated a significant increase in M levels until the 3-month time point, thereafter stabilization was evident. Furthermore, M levels in the apical segment were lower than those in the medial and basal segments. EIV decreased from initial stimulation to the 3-month time point and was then stable through the study follow up. Interestingly, the finding of higher EIV in the apical segment may be attributed to the physical characteristics of the Med-El electrode. In conclusion, the pattern of stabilization of M levels found in the present study is similar to that reported for children using other devices. The data presented here may be useful as a guideline for programming M levels and monitoring EIV in infants and young children. They may further help clinicians to identify those children that fall outside the 'typical' range.

Acoustic Impedance Tests↗
PubMed2005

Is mastoidectomy indispensable in cochlear implant surgery?

OBJECTIVE: To challenge the need for mastoidectomy in cochlear implant (CI) surgery by comparing the advantages and disadvantages of the classic technique for CI, the mastoidectomy posterior tympanotomy approach (MPTA), with the suprameatal approach (SMA), a nonmastoidectomy approach. STUDY DESIGN AND SETTING: A retrospective study of 290 patients who underwent cochlear implantation in our department between 1989 and 2002. One hundred fifty-seven of them underwent the MPTA and 133 underwent the SMA. The ability of the electrode to expand in the MPTA patients who were reoperated on was examined, as was the influence of mastoidectomy on the course of chronic secretory otitis media (SOM) in a group of 56 children who suffered from chronic SOM prior to implantation. RESULTS: In all 4 reoperated children, in whom the MPTA was used, the mastoid was completely closed by bony regrowth on the cortical portion of the mastoid and the mastoid cavity was obliterated. The electrode had been embedded in dense fibrous tissue and bony spicule, preventing electrode expansion. Mastoidectomy was found to have no influence on the course of chronic SOM. The rate of postoperative SOM was found to be equal in 40 children who were operated on using the MPTA compared with 16 operated on using the SMA. CONCLUSION: Using a nonmastoidectomy approach, such as the SMA, provides a wide exposure of the middle ear and promontory and thus enables a well-controlled cochleostomy site and safe insertion of the electrode into the cochlea. Mastoidectomy in CI surgery is not indispensable; it may cause more disadvantages than advantages.

Adolescent↗
PubMed2005

Mastoidectomy for acute otomastoiditis: our experience.

We conducted a retrospective study of 53 mastoidectomies in 51 patients with acute otomastoiditis. In 26 cases (49.1%), surgery had been performed within 48 hours of the development of symptoms. The most common complication of acute otomastoiditis was subperiosteal abscess, which occurred in 37 cases (69.8%). Intracranial complications were seen in 6 cases (11.3%). The most common pathogens isolated from subperiosteal abscesses, the mastoid cavity, and intracranial collections were Streptococcus spp and Staphylococcus aureus. In 14 cases (26.4%), conservative treatment failed to cure acute otomastoiditis; such cases should raise a suspicion of a subperiosteal abscess, an underlying cholesteatoma, or an infection caused by gram-negative bacteria. Upon hospital admission, patients should receive antibiotics that are effective against both gram-positive and gram-negative organisms. Patients with intracranial complications or facial nerve paralysis may require a combination of two or more antibiotics. Long-term follow-up is highly recommended.

Acute Disease↗
PubMed2004

Bacteriology of mastoid subperiosteal abscess in children.

OBJECTIVE: Subperiosteal abscess (SA) is the most frequent complication of acute mastoiditis (AM). Of pathogens cultured from the external auditory canal or middle ear during myringotomy, 15% may be different from microorganisms isolated from the SA. We suggest, therefore, that only cultures obtained from the abscess cavity can truly reflect the bacteriology of this complication of AM. The purpose of our study was to analyze the infectious agents which cause SA and mastoid cortex erosion in children. MATERIAL AND METHODS: The medical records of 35 children who underwent mastoidectomy for SA between May 1984 and April 2002 were evaluated. RESULTS: Mastoid cortex erosion was found at surgery in 72.7% of abscesses Purulent discharge was obtained from the SA cavity in 28 cases. The commonest pathogens isolated in these cases, as well as in 18 cases of mastoid cortex erosion, were Staphylococcus aureus and Streptococcus pyogenes, followed by Streptococcus pneumoniae. Hemophilus influenzae, Pseudomonas aeruginosa, Escherichia coli and Klebsiella pneumoniae. Sterile culture was found in 25% of cases. CONCLUSIONS: Mastoid SA is a unilateral disease that can recur. Early administration of anti-Staphylococcus medications should be considered for patients with SA as a complication of AM.

Abscess↗
PubMed2004

The suprameatal approach: an alternative surgical approach to cochlear implantation.

The suprameatal approach is an alternative method for performing cochlear implantation developed in the Sheba Medical Center in 1999. This technique eliminates the need for mastoidectomy and posterior tympanotomy. The middle ear is entered through a retroauricular tympanotomy flap, and the electrode is introduced into the cochlea via a tunnel drilled in the suprameatal region superior to Henle's spine. The suprameatal approach is a simple and safe technique that does not endanger the facial nerve nor the chorda tympani. A wide exposure of the promontory enables exact determination of scala tympani and smooth introduction of the electrodes into the cochlea. This technique may also be used in malformed or ossified cochlea. Until now 140 patients were operated in our department and an additional 48 patients were operated on in the department of Otorhinolaryngology at the University of Vienna employing the suprameatal approach technique.

Adult↗
PubMed2004

Quality of life following parotidectomy for malignant and benign disease.

Parotidectomy is performed for benign or malignant tumors and for selected benign inflammatory and autoimmune conditions. Possible associated complications include facial nerve paralysis, pain, loss of sensation, gustatory sweating, and facial scarring. Global quality of life in patients undergoing parotidectomy has not been reported. The implications of facial surgery with the catastrophic potential of facial nerve paralysis may severely affect quality of life. A quality-of-life study was conducted in patients undergoing parotidectomy for benign and malignant diseases to define the significance of associated morbidity and its impact on quality of life. A quality-of-life instrument was specifically created, based on the principles of the University of Washington Quality of Life questionnaire, and mailed to the patients. Questions addressed recognized complications of parotidectomy. Patient group results were compared for age above and below 45 years, sex, benign versus malignant disease, presence or absence of Frey syndrome, and presence or absence of benign pleomorphic adenoma. Forty-six percent of 125 patients meeting the study criteria fully replied to the questionnaire. The global health score was 3.5, corresponding with "good" to "very good." Except for local sensation, which had a score of 50, all other domains scored above 76. Change in appearance, gustatory sweating, and pain were reported by 70 percent, 57 percent, and 30 percent, respectively. Importance attributed to all domains except facial function was low. Pain was encountered significantly less in patients younger than 45 years of age, and scores for appearance were also highly significant in this age group. Postoperative sequelae were noted in the majority of patients. The dominant sequelae were altered sensation, change in appearance, Frey syndrome, and pain. A degree of permanent postoperative facial nerve impairment was reported by 10 patients. Nevertheless, overall, parotidectomy does not seem to severely affect quality of life.

Adult↗
PubMed2004

Quality of life of well-differentiated thyroid carcinoma patients.

The thyroid gland is the second most common site for malignancy in the head and neck region. Quality of life (QOL) of thyroid cancer patients has not been studied directly. The QOL of long-term thyroid carcinoma patients was investigated. A standardized set of questions based on the University of Washington QOL questionnaire for head and neck cancer with specific domains associated with thyroid disease was created. This questionnaire was mailed to patients who underwent total thyroidectomy for well-differentiated cancer in the department of Otolaryngology--Head and Neck surgery at the Chaim Sheba Medical Centre in Israel between the years 1994-2000. Seventy-eight patients undergoing total thyroidectomy were identified. Forty-eight patients were excluded and 20 out of the 30 remaining patients responded to the questionnaires. Six were male and 14 female, 12 were under the age of 45 (these 12 patients were staged as stage 1). Eleven patients underwent neck dissection. General health and QOL were significantly better for the younger age group and so was the calcium balance score. General health and QOL were significantly better for patients undergoing neck dissection. The overall QOL score was 3.8 conforming with 'good' in the questionnaire. Surgery and initial radioiodine treatment scored 6.75 and 6.9 respectively in the distressing scale (0-10 range: 10 = most distressing). The highest distress was encountered during withdrawal from thyroid hormone. Women rated the importance of proper replacement therapy significantly higher than men. Global low scores were found for employment and for effective L-thyroxine replacement therapy. Overall, QOL in these patients was good although lower than expected when compared with other forms of cancer. Age and gender-related differences were noted. Better QOL in neck dissection patients is probably associated with age under 45 years. High distress scores for hormone withdrawal during periodical imaging correspond with former reports and supports use of Thyrogen. Better hormone balance is warranted for this group.

Adolescent↗
PubMed2004

NRT-based versus behavioral-based MAP: a comparison of parameters and speech perception in young children.

The present study was designed to evaluate the effect of neural response telemetry (NRT)-based cochlear implant (CI) programming versus behavioral-based programming on electrical stimulation parameters (MAP) threshold (T) and comfortable (C) levels and speech perception abilities in young children, during the first year of implant use. Ten congenitally deaf children at the age of 12-39 months (mean age: 25.2 months) implanted with the Nucleus 24R(CS) CI participated in the study. The group was randomly divided into two: (1) NRT-based MAP group (n = 5) consisted of children who were programmed using intra-operative NRT measurements; (2) behavioral-based MAP group (n = 5) consisted of children who were programmed using the behavioral responses of the patients. MAP parameters as well as sound-field aided thresholds and speech perception abilities were compared between the two groups at consecutive programming sessions: 1, 3, 6, and 12 months post initial stimulation. Results indicated no significant differences among NRT-based MAPs and behavioral-based MAPs. Although MAP profiles at initial stimulation differed in the apical region, these differences decreased with time. In addition, a gradual increase of T and C levels of NRT-based MAPs as well as those of behavioral-based MAPs was evident until the 1-month time point, thereafter stabilization occurred. Sound-field aided thresholds improved with time for both groups; however, they were found to be significantly better for the NRT-based MAP group. Despite these differences, speech perception abilities were comparable among groups at 12 months post initial stimulation. NRT-based programming was found to be significantly shorter than behavioral-based programming. In conclusion, for this small group of children, our findings support the use of NRT for programming of young children during the initial period after implantation.

Acoustic Stimulation↗
PubMed2003

Preservation of the facial artery in excision of the submandibular salivary gland.

BACKGROUND: The accepted method for submandibular gland excision traditionally includes ligation of the facial artery (FA) as suggested by a host of surgical atlases. Preservation of the FA may be significant in reconstructive procedures of the head and neck and its ligation may altogether be obviated. OBJECTIVE: Prospective feasibility study of FA preservation in submandibular gland excision. MATERIALS AND METHODS: Patients undergoing excision of the submandibular salivary glands from September 1999 through August 2001 were prospectively included. The FA was dissected and only its glandular branches ligated. Exclusion criteria were primary benign or malignant tumors of the submandibular salivary gland or metastatic disease involving the gland or level I of the neck. In cases where the primary tumor involved the floor of mouth, anterior tongue or mandible, resection of level I contents included the FA even in N0 necks. RESULTS AND CONCLUSIONS: 104 patients (116 procedures) were included in the study. 81 patients underwent resection of the gland with preservation of the FA. The vessel was sacrificed in 35 necks because of metastases or primary tumor and in two cases of chronic sialadenitis. One patient had a postoperative hematoma following neck dissection requiring re-exploration. The source of bleeding was not found to be related to the FA. Contrary to accepted methodology, the FA may readily be preserved in surgery of the submandibular salivary glands. We suggest preservation of the FA in all cases of procedures for benign disease and in selected cases of malignancy.

Aged↗
PubMed2003

Cochlear implantation in a child with osteogenesis imperfecta.

Osteogenesis imperfecta (OI) is a hereditary disease of connective tissue and affects bone, dentine, sclera, joint, tendon, blood vessels, heart valves, and skin. Approximately 50% of the adult patients with OI have associated hearing impairment. To date, only three cases of cochlear implantation in adults with OI have been reported, but none in children. We present a case of cochlear implantation in a congenitally deaf 6-year-old boy with OI. The Nucleus 24 Contour device was successfully implanted using the suprameatal approach (SMA). At 6 months post-initial stimulation there was no evidence of non-acoustic nerve excitation (i.e. facial twitching) or discomfort, and significant progress in auditory abilities was manifested by open set word identification.

Audiometry↗
PubMed2003

Changes over time in electrical stimulation levels and electrode impedance values in children using the Nucleus 24M cochlear implant.

OBJECTIVE: The present study was designed to evaluate changes in psycho-electric parameters, i.e. threshold levels, comfortable levels, dynamic range, and electrode impedance values during the 1st year post-implantation, in children using the Nucleus 24M cochlear implant system. METHODS: The maps of 25 pre-lingual children programmed with ACE strategy in Monopolar 1 + 2 mode were examined at five time points: connection, 1, 3, 6, and 12 months post-initial stimulation. Maps and electrode impedance values were analyzed according to three cochlear segments: basal, medial, and apical. RESULTS: Significant elevations of thresholds, comfortable levels, and dynamic range were found during the first few months of implant use. Specifically, threshold increased and dynamic range widened until the 3 months visit, whereas comfortable levels continued to increase until the 6 months visit, thereafter levels stabilized. Electrode impedance values decreased significantly from connection to the 1-month visit thereafter a stabilization of values was evident. In addition, thresholds and comfortable levels were found to be significantly lower in the apical segment, whereas dynamic range and electrode impedance values did not differ among the cochlear segments. CONCLUSIONS: Significant changes in psycho-electric parameters and electrode impedance values were evident during the first 6 months of implant use. Given the important role of an optimal map for speech perception, frequent programming sessions during the first few months of implant use are essential.

Acoustic Impedance Tests↗
PubMed2003

Amputation neuromas after neck dissection.

OBJECTIVE: We sought to define the incidence of neuroma formation after neck dissection in a large series of patients. METHODS: One hundred fifty-three patients who were seen during a 2-year period (followed for 3 months to 10 years; mean, 52 months) were evaluated for neuroma formation after neck dissection (185 procedures). Cut nerve edges were not routinely ligated or cauterized. RESULTS: Operative records indicated that except for 4 cases, the stumps of the great auricular nerve and cervical branches were left intact after resection. No cases of palpable neuromas were found. In one case of a revised neck, a small macroscopically indiscernible nodule was histologically defined as neuroma. CONCLUSION: No neuromas were discovered in our series of neck dissection cases. If found, it is imperative these lesions be differentiated from recurrent cancer. Our results do not support any interference with cut nerve edges.

Adult↗
PubMed2003

The role of mastoidectomy in cochlear implant surgery.

OBJECTIVE: The classical technique for cochlear implantation (CI) involves mastoidectomy and posterior tympanotomy. The question raised in this work is whether mastoidectomy is indispensable in CI surgery. MATERIAL AND METHODS: The advantages and disadvantages of performing mastoidectomy during CI surgery were weighed, in particular the effect of mastoidectomy on chronic secretory otitis media (SOM) and the ability of the electrode to expand in the mastoid during skull growth. RESULTS: No effect of mastoidectomy on chronic SOM was found and the assumption that the electrode in the mastoid cavity has the ability to expand during skull growth was not proven. Eliminating mastoidectomy in CI surgery simplifies the procedure, shortens the duration of surgery, minimizes the amount of drilling and provides broader, better exposure of the middle ear and promontory. Mastoidectomy was found not to be obligatory in CI surgery and in fact may have more disadvantages than advantages. CONCLUSION: The development of alternative CT techniques which eliminate the need for mastoidectomy is justified.

Adolescent↗
PubMed2003

Changes over time in the psycho-electric parameters in children with cochlear implants.

Information regarding typical changes in electrical stimulation levels during different stages post-implantation in children is scarce. Clinically, this information can serve as a general guideline to the nature and frequency of these changes, and consequently help to determine programming schedules that would optimize performance with the implant. Furthermore, it may have implications for the design of cochlear implants, and for monitoring the condition of the implanted cochlea. The main goal of the present study was, therefore, to evaluate changes over time in psycho-electric parameters, i.e. threshold levels, comfortable levels, and dynamic range, in children with the Nucleus 22 cochlear implant system. The maps of 37 prelingual children were examined at five time intervals: 1, 6, 12, 18 and 24 months post-connection. Maps were analyzed according to three cochlear segments: basal, medial, and apical. The results indicated significant changes in the psycho-electric parameters during the first 2 years post-implantation. Specifically, threshold (T) levels increased significantly during the first year and stabilized during the second year, whereas comfort (C) levels and dynamic range (DR) increased significantly during the entire 2-year follow-up. In addition, psycho-electric parameters varied among the different cochlear segments, resulting in a narrower DR in the basal one. Regardless of the underlying cause for these changes, the results of the present study suggest that, in children, the stabilization of psycho-electric parameters is a prolonged, gradual process. Since psycho-electric parameters play an important role in speech perception, these findings emphasize the need for frequent programming in the first 2 years of implant use in children.

Analysis of Variance↗
PubMed2002

Quality of life of nasopharyngeal carcinoma patients.

BACKGROUND: Quality of life (QOL) issues in patients with head and neck carcinoma are of importance beyond the incidence of these tumors because of the impact of the disease and its treatment on external appearance and function of the upper aerodigestive tract. Nasopharyngeal carcinoma (NPC) patients comprise a unique subgroup in whom, to our knowledge, QOL has not been studied directly. METHODS: Adult patients with NPC treated during the past 15 years at the Chaim Sheba Medical Center with a minimum follow-up of 6 months were included in the current study. Patients were mailed the revised University of Washington quality of life (UW-QOL) questionnaire and data pertaining to their disease were recorded. Patients with recurrent disease or another malignancy or those whose present status could not be ascertained were excluded from the study. QOL scores were analyzed based on treatment, disease stage, and patient age. RESULTS: Twenty-eight patients of 35 disease-free patients (80%) responded to the questionnaire sent to patients meeting the study criteria. The mean score for general health was 3.1 (range, 1-5). Pain was not a significant factor. Other domains without noteworthy problems were speech and shoulder disability. The majority of patients described their appearance as normal or with minor changes, and questions concerning activity, recreation/entertainment, employment, and swallowing all scored > 70 (range, 0-100). Dry mouth, chewing, and ear problems were of major concern with the majority of patients and affected the QOL indices. Nevertheless, the overall mean QOL score of these patients was rated as "good" (4.2 on a scale of 1-6). CONCLUSIONS: In the current study, patients with NPC reported ear problems, difficulties in chewing, and dry mouth but their overall QOL appeared to be good. Ear problems such as secretory otitis media should be recognized at the time of presentation and treated. Conformal radiotherapy techniques sparing the salivary glands and temporal bone most likely will be useful in reducing the morbidity associated with treatment.

Adult↗
PubMed2002

Rhino-orbital and rhino-orbito-cerebral mucormycosis.

BACKGROUND: Rhino-orbito-cerebral mucormycosis (ROCM) is a devastating infection of immunocompromised hosts. We present our experience with 19 ROCM cases and attempt to define preferred diagnostic and treatment protocols. METHODS: All had tissue biopsies obtained studied by direct smear, histologic studies, and cultures. Imaging was obtained in 14 cases. RESULTS: Sixteen patients presented between August and November. Six had mixed fungal infections. Seven patients had end-stage underlying disease or infection and did not undergo surgery and 4 had an indolent form of disease. Patients were treated by surgery and by amphotericin B. The overall survival was 47%. CONCLUSIONS: ROCM may have seasonal incidence peaking in the fall and early winter. The therapeutic approach should be unchanged in cases of mixed fungal infections. Amphotericin B with aggressive debridement remains the mainstay of treatment. Early recognition and treatment are essential. A presentation and survival-dependent classification of ROCM are offered.

Adult↗