Pediatric Cochlear Implantation: Strategies to Accommodate for Head Growth

1989 ◽  
Vol 101 (1) ◽  
pp. 38-46 ◽  
Author(s):  
David R. Marks ◽  
Robert K. Jackler ◽  
Grant J. Bates ◽  
Sheldon Greenberg
Keyword(s):  
Connective Tissue ◽  
Cochlear Implantation ◽  
Soft Tissues ◽  
Effective Means ◽  
Fibrous Tissue ◽  
Initial Study ◽  
Parietal Bone ◽  
Mastoid Cavity ◽  
Lead Wire ◽  
Head Growth

Accommodation for head growth presents one of several challenges unique to pediatric cochlear implantation. Given contemporary cochlear implant device designs, an electrode cable implanted at the age of 2 years must extend 2 to 3 cm as the head grows during childhood. In an initial study we found that model lead wires with redundant loops extended effectively when they were maintained within air-containing spaces such as the mastoid cavity or middle ear space. However, when looped leads traversed soft tissues overlying the parietal bone, they became embedded in fibrous tissue and did not extend. The present study evaluated three different configurations of expansile devices that were enclosed In polytetrafluoroethylene (PTFE) envelopes to deter fibrous ingrowth. This simple strategy was designed to ensure effective cable extension over cable pathlengths by protecting the redundant leads from any mechanically significant connective tissue ingrowth. Twelve such devices were implanted across the calvaria of four newly weaned plglets. Skull growth and changes in electrode dimensions were documented by sequential computed tomographic scans. At 3 months of age, cranial circumferences had increased substantially. Animals were then killed, the model cable extension appliances examined physically, and their implantation sites examined histologically. For all experimental devices, extension of redundant lead wires was satisfactory, and there was no mechanically significant invasion of fibrous connective tissue into the PTFE envelope. This indicates that enclosure of excess lead wire within a PTFE envelope may be an effective means of inhibiting fibrous Ingrowth. This strategy should prove useful for ensuring effective electrode cable extension In cochlear implants applied in young children.

scholarly journals Az emberi halántékcsontnak a csecsemő- és kisgyermekkori cochlearis implantáció szempontjából kiemelkedően fontos dimenziói. Klinikoradiológiai vizsgálat

2019 ◽  
Vol 160 (24) ◽  
pp. 936-943 ◽  
Author(s):  
Ádám Perényi ◽  
József Jóri ◽  
Miklós Csanády ◽  
László Rovó
Keyword(s):  
Temporal Bone ◽  
Cochlear Implantation ◽  
Soft Tissues ◽  
Round Window ◽  
Young Age ◽  
Mastoid Cavity ◽  
Tomographic Images ◽  
Computed Tomographic ◽  
Facial Recess ◽  
Young Subjects

Abstract: Introduction: Early cochlear implantation enables prelingual deaf individuals to become full members of the hearing society. Although early diagnostics are widely accessible and enable early rehabilitation, implant surgery often may be delayed due to a candidate’s young age. Aim: The authors’ objectives were to determine the anatomical parameters of the pediatric and adult temporal bone that are relevant to cochlear implantation and to ascertain the differences between them in order to assess whether the anatomical differences could influence the surgical technique and the timing of surgery. Method: Along with a survey of the literature, findings from the authors own cochlear implantees were assessed with respect to the most relevant dimensions of the internal electronic package, including the stimulating electrode of the cochlear implant, by measuring the squama of the temporal bone, the mastoid cavity and the facial recess on high resolution computed tomographic images. Results: The skull and the overlying soft tissues proved to be thinner and the mastoid cavity was less developed in children than in adults, while no significant changes were noted in the size of the facial recess. Conclusions: It is recommended to choose modern, thin implants that do not require sinking the implant package into a bone bed. Less bone work in infants and children enables excellent visualization of the round window through the underdeveloped mastoid cavity, which makes the procedure less time-consuming and minimally invasive. Indeed, a young age should alert ear surgeons to be cautious, but no higher risk of injury to important structures is predicted for young subjects than those that might occur in adults. Orv Hetil. 2019; 160(24): 936–943.

scholarly journals SYNERGISTIC EFFECT OF QUERCETIN AND EPIGALLOCATECHIN-3-GALLATE AS AGENTS TO PREVENT CONNECTIVE TISSUE DISINTEGRATION IN THE PERIODONTIUM OF RATS UNDER SYSTEMIC AND LOCAL ADMINISTRATION OF LIPOPOLISACCHARIDE OF SALMONELLA TYPHI

2019 ◽  
Vol 23 (5-6) ◽  
pp. 42-44
Author(s):  
A.M. Yelins’ka ◽  
V.O. Kostenko
Keyword(s):  
Connective Tissue ◽  
Soft Tissues ◽  
Alveolar Bone ◽  
Effective Means ◽  
Organic Matrix ◽  
Water Soluble ◽  
Soluble Form ◽  
Experimental Conditions ◽  
Periodontal Tissues ◽  
White Rats

The aim of the present study was to investigate the co-effect produced by water-soluble form of quercetin and epigallocatechin-3-gallate (EGCG) on biochemical markers of periodontal organic matrix depolimerization under systemic administration and local application of S. typhi lipopolisaccharide (LPS). The studies were conducted on 30 white rats of the Wistar line weighing 180-220 g, divided into 5 groups: the 1st included intact animals, the 2nd was made up of animals after the combined systemic and local LPS administration, the 3rd and 4th groups included animals, which were being given injections with water-soluble form of quercetin (10 mg / kg) and EGCG (21.1 mg / kg) respectively 3 times a week, starting on the 30th day of the systemic LPS administration, and the 5th group involved rats, which were injected with co-administered water-soluble form of quercetin and EGCG. It has been found out that the co-effect produced by quercetin and EGCG under systemic and local LPS administration is accompanied with reduced concentration of N-acetylneuraminic acid (NANA) by 31.8 and 32.8% respectively in the soft periodontal tissues compared with values for the animals received separate quercetin and EGCG during the experiment. However, no differences have been detected between the groups exposed to combined or separate action of the above mentioned agents in the experiment when assessing free hydroxyproline (FHP) and glycosaminoglycans (GAGs) content in the soft tissues of periodontium. At the same time combined use of quercetin and EGCG under experimental conditions led to the decrease in the FHP content in the alveolar bone by 24.5 and 20.2% respectively compared with values for the animals received separate quercetin and EGCG. NANA concentration was reduced by 35.0 and 41.3% respectively. Thus, the co-administration of water-soluble form of quercetin and epigallocatechin-3-gallate under systemic and local introducing of S. typhi lipopolysaccharide has been proven to be more effective means for preventing and correcting periodontal connective tissue disruption than this occurs at separate administration of each of the polyphenols.

scholarly journals Biological Width around One- and Two-Piece Implants Retrieved from Human Jaws

2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Ricardo Judgar ◽  
Gabriela Giro ◽  
Elton Zenobio ◽  
Paulo G. Coelho ◽  
Magda Feres ◽  
...  
Keyword(s):  
Connective Tissue ◽  
Soft Tissues ◽  
Fibrous Tissue ◽  
Case Series ◽  
Surrounding Tissue ◽  
Marginal Bone Loss ◽  
Edentulous Patients ◽  
Biologic Width ◽  
Tissue Attachment ◽  
Epithelial Junction

Several histologic studies regarding peri-implant soft tissues and biological width around dental implants have been done in animals. However, these findings in human peri-implant soft tissues are very scarce. Therefore, the aim of this case series was to compare the biological width around unloaded one- and two-piece implants retrieved from human jaws. Eight partially edentulous patients received 2 test implants in the posterior mandible: one-piece (solid implants that comprise implant and abutment in one piece) and two-piece (external hexagon with a healing abutment) implants. After 4 months of healing, the implants and surrounding tissue were removed for histologic analysis. The retrieved implants showed healthy peri-implant bone and exhibited early stages of maturation. Marginal bone loss, gaps, and fibrous tissue were not present around retrieved specimens. The biologic width dimension ranged between 2.55 ± 0.16 and 3.26 ± 0.15 to one- and two-piece implants, respectively (P<0.05). This difference was influenced by the connective tissue attachment, while sulcus depth and epithelial junction presented the same dimension for both groups (P>0.05). Within the limits of this study, it could be shown that two-piece implants resulted in the thickening of the connective tissue attachment, resulting in the increase of the biological width, when compared to one-piece implants.

scholarly journals The Symmetric 3D Organization of Connective Tissue around Implant Abutment: A Key-Issue to Prevent Bone Resorption

Symmetry ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1126
Author(s):  
Giovanna Iezzi ◽  
Francesca Di Lillo ◽  
Michele Furlani ◽  
Marco Degidi ◽  
Adriano Piattelli ◽  
...  
Keyword(s):  
Bone Resorption ◽  
Connective Tissue ◽  
Inflammatory Cell ◽  
Soft Tissues ◽  
Three Dimensional ◽  
Collagen Fibers ◽  
Inflammatory Cell Infiltration ◽  
Cell Infiltration ◽  
Oral Epithelium ◽  
Implant Abutment

Symmetric and well-organized connective tissues around the longitudinal implant axis were hypothesized to decrease early bone resorption by reducing inflammatory cell infiltration. Previous studies that referred to the connective tissue around implant and abutments were based on two-dimensional investigations; however, only advanced three-dimensional characterizations could evidence the organization of connective tissue microarchitecture in the attempt of finding new strategies to reduce inflammatory cell infiltration. We retrieved three implants with a cone morse implant–abutment connection from patients; they were investigated by high-resolution X-ray phase-contrast microtomography, cross-linking the obtained information with histologic results. We observed transverse and longitudinal orientated collagen bundles intertwining with each other. In the longitudinal planes, it was observed that the closer the fiber bundles were to the implant, the more symmetric and regular their course was. The transverse bundles of collagen fibers were observed as semicircular, intersecting in the lamina propria of the mucosa and ending in the oral epithelium. No collagen fibers were found radial to the implant surface. This intertwining three-dimensional pattern seems to favor the stabilization of the soft tissues around the implants, preventing inflammatory cell apical migration and, consequently, preventing bone resorption and implant failure. This fact, according to the authors’ best knowledge, has never been reported in the literature and might be due to the physical forces acting on fibroblasts and on the collagen produced by the fibroblasts themselves, in areas close to the implant and to the symmetric geometry of the implant itself.

scholarly journals Cochlear Implantation Following Explorative Tympanotomy in Patients With Sudden Sensorineural Hearing Loss: Surgical Features and Audiological Outcomes

2021 ◽  
pp. 014556132110091
Author(s):  
Robin Rupp ◽  
Joachim Hornung ◽  
Matthias Balk ◽  
Matti Sievert ◽  
Sarina Müller ◽  
...  
Keyword(s):  
Hearing Loss ◽  
Connective Tissue ◽  
Sensorineural Hearing Loss ◽  
Cochlear Implantation ◽  
Round Window ◽  
Sudden Sensorineural Hearing Loss ◽  
Sensorineural Hearing ◽  
Round Window Membrane ◽  
Hearing Results ◽  
Round Window Niche

Objective: To investigate the anatomical status of the round window niche and hearing outcome of cochlear implantation (CI) after explorative tympanotomy (ExT) with sealing of the round window membrane in patients with sudden sensorineural hearing loss at a tertiary referral medical center. Methods: Between January 1, 2007, and July 30, 2020, 1602 patients underwent CI at our department. Out of these, all patients previously treated by ExT with sealing of the round window membrane because of unilateral sudden hearing loss were included in the study. A retrospective chart review was conducted concerning method of round window membrane sealing, intraoperative findings during CI, postoperative imaging, and hearing results. Results: Twenty one patients (9 females; 8 right ears; 54.3 years [± 12.9 years]) underwent ExT with sealing of the round window membrane with subsequent CI after 26.6 months (± 32.9 mo) on average. During CI, in 76% of cases (n = 16), the round window niche was blocked by connective tissue due to the previous intervention but could be removed completely in all cases. The connective tissue itself and its removal had no detrimental effects on the round window membrane. Postoperative computed tomography scan showed no electrode dislocation. Mean postoperative word recognition score after 3 months was 57.4% (± 17.2%) and improved significantly to 73.1% (± 16.4%, P = .005) after 2 years. Conclusion: Performing CI after preceding ExT, connective tissue has to be expected blocking the round window niche. Remaining tissue can be removed safely and does not alter the round window membrane allowing for a proper electrode insertion. Short- and long-term hearing results are satisfactory. Consequently, ExT with sealing of the round window membrane in patients with sudden sensorineural hearing loss does not impede subsequent CI that can still be performed safely.

Biological Response to Wollastonite Doped α-Tricalcium Phosphate Implants in Hard and Soft Tissues in Rats

2008 ◽  
Vol 396-398 ◽  
pp. 7-10 ◽  
Author(s):  
Ana Maria Minarelli Gaspar ◽  
Sybele Saska ◽  
R. García Carrodeguas ◽  
A.H. De Aza ◽  
P. Pena ◽  
...  
Keyword(s):  
Connective Tissue ◽  
Bone Formation ◽  
Bone Tissue ◽  
Tricalcium Phosphate ◽  
Rattus Norvegicus ◽  
Soft Tissues ◽  
Subcutaneous Tissue ◽  
Biological Response ◽  
New Bone Formation ◽  
Rat Bone

The biological response following subcutaneous and bone implantation of β-wollastonite(β-W)-doped α-tricalcium phosphate bioceramics in rats was evaluated. Tested materials were: tricalcium phosphate (TCP), consisting of a mixture of α- and β-polymorphs; TCP doped with 5 wt. % of β-W (TCP5W), composed of α-TCP as only crystalline phase; and TCP doped with 15 wt. % of β-W (TCP15), containing crystalline α-TCP and β-W. Cylinders of 2x1 mm were implanted in tibiae and backs of adult male Rattus norvegicus, Holtzman rats. After 7, 30 and 120 days, animals were sacrificed and the tissue blocks containing the implants were excised, fixed and processed for histological examination. TCP, TCP5W and TCP15W implants were biocompatible but neither bioactive nor biodegradable in rat subcutaneous tissue. They were not osteoinductive in connective tissue either. However, in rat bone tissue β-W-doped α-TCP implants (TCP5W and TCP15W) were bioactive, biodegradable and osteoconductive. The rates of biodegradation and new bone formation observed for TCP5W and TCP15W implants in rat bone tissue were greater than for non-doped TCP.

Comparative analysis of the effectiveness of surgical techniques for the treatment of Miller Class I gingival recessions

2021 ◽  
Vol 26 (2) ◽  
pp. 150-157
Author(s):  
R. R. Farkhshatova ◽  
L. P. Gerasimova ◽  
I. T. Yunusov
Keyword(s):  
Connective Tissue ◽  
Soft Tissues ◽  
Platelet Rich Plasma ◽  
Class I ◽  
Study Group ◽  
Connective Tissue Graft ◽  
Group I ◽  
Autologous Platelet Rich Plasma ◽  
Group Ii ◽  
Autologous Platelet

Relevance. It is currently relevant to study and compare the effectiveness of the autologous connective tissue grafts and the combination of collagen-based and autologous platelet-rich plasma in the surgical treatment of Miller Class I gingival recessions.Materials and methods. We examined and treated 48 (20 male (41.67%) and 28 female (58.33%)) patients aged from 25 to 40 years with Miller Class I gingival recessions. All gingival recessions were treated surgically using a modified twolayer tunnel technique. The patients were divided into two groups according to the graft type. Group I (24 patients (50%) had a connective tissue graft from the hard palate. Group II (24 patients (50%) used the combination of the autologous platelet-rich plasma and 3D collagen matrix Fibromatrix for the regeneration of oral soft tissues. We removed the sutures on the 14th day. The patients were followed up on the 7th and 14th days and in 1.3 months.Results. 48 Miller Class I gingival recessions were treated between 2018 and 2020. The depth of gingival recessions averaged 3.5 ± 1.13 mm before treatment. The level of the attached keratinized gingiva regarding the cementoenamel junction significantly (p < 0.001) improved in both groups after the surgery. The width and thickness of the keratinized gingiva best increased in group II. The mean effectiveness of gingival recession treatment was 84% in study group I and 96% – in study group II. Pain syndrome, fibrinous plaque and soft tissue edema were insignificant in group II.Conclusion. The combination of the autologous platelet-rich plasma and Fibromatrix, collagen 3D matrix, for the regeneration of the oral soft tissues is a more effective technique for the treatment of Miller Class I gingival recessions. This technique has several advantages. It is minimally invasive, less painful, soft tissue postoperative swelling is less and the received volume of the attached keratinized gums is larger than with a connective tissue graft. 

scholarly journals Histopathology of the Human Inner Ear in the Cogan Syndrome with Cochlear Implantation

2017 ◽  
Vol 22 (2) ◽  
pp. 116-123 ◽  
Author(s):  
Takefumi Kamakura ◽  
Daniel J. Lee ◽  
Barbara S. Herrmann ◽  
Joseph B. Nadol Jr.
Keyword(s):  
Bone Formation ◽  
Cochlear Implantation ◽  
Fibrous Tissue ◽  
Spiral Ganglion ◽  
New Bone Formation ◽  
Cogan Syndrome ◽  
Interstitial Keratitis ◽  
The Right ◽  
Ganglion Neurons ◽  
Temporal Bones

The Cogan syndrome is a rare disorder characterized by nonsyphilitic interstitial keratitis and audiovestibular symptoms. Profound sensorineural hearing loss has been reported in approximately half of the patients with the Cogan syndrome resulting in candidacy for cochlear implantation in some patients. The current study is the first histopathologic report on the temporal bones of a patient with the Cogan syndrome who during life underwent bilateral cochlear implantation. Preoperative MRI revealed tissue with high density in the basal turns of both cochleae and both vestibular systems consistent with fibrous tissue due to labyrinthitis. Histopathology demonstrated fibrous tissue and new bone formation within the cochlea and vestibular apparatus, worse on the right. Severe degeneration of the vestibular end organs and new bone formation in the labyrinth were seen more on the right than on the left. Although severe bilateral degeneration of the spiral ganglion neurons was seen, especially on the right, the postoperative word discrimination score was between 50 and 60% bilaterally. Impedance measures were generally higher in the right ear, possibly related to more fibrous tissue and new bone found in the scala tympani on the right side.

Meatoplasty keloid: a rare lesion treated with an unusual surgical approach

2006 ◽  
Vol 120 (7) ◽  
pp. 594-596
Author(s):  
N P Shine ◽  
K Lew
Keyword(s):  
Unusual Case ◽  
Steroid Injection ◽  
Fibrous Tissue ◽  
Surgical Excision ◽  
Mastoid Cavity ◽  
Ear Piercing ◽  
Keloid Scarring ◽  
Microscopic Evaluation ◽  
Keloid Formation ◽  
Rare Lesion

Keloid scarring is a benign hyperproliferation of fibrous tissue occurring at a wound healing site. Keloid formation related to the ear is generally the result of ear-piercing, mainly causing cosmetic disfigurement. We present an unusual case of keloid formation at a previous meatoplasty incision scar in a 10-year-old Caucasian with a modified radical mastoid cavity. This lesion prevented the cavity from self-cleaning and obstructed microscopic evaluation of the cavity. Treatment was successfully performed by surgical excision, with closure of the defect using supra-keloid skin flaps, followed by serial steroid injection therapy.

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