Radiological diagnosis of incomplete partition type I versus type II: significance for cochlear implantation

Background: Patients with cochlear malformations were long considered poor candidates for cochlear implantation (CI), and surgical approaches different than the standard facial recess approach were used to access the inner ear. There is no previous long-term follow-up of a patient with significantly malformed inner ear operated through an untraditional route and requiring a revision surgery. Purpose: This case provides a long-term follow-up from the initial surgery, a short-term follow-up from the revision surgery, and it illustrates the evolving classification of inner ear malformations as well as the potential problems associated with nonstandard approaches to the cochlea. Research Design: A case report. Intervention: Herein, we report a case of revision CI in a patient with incomplete partition type I, through the round window via a facial recess approach, 18 yr after an initial implantation via a transmastoid labyrinthotomy approach. Results: The patient had an uncomplicated surgery, and after activation, she noted auditory perception on all electrodes without facial stimulation. A sound field sound awareness threshold was obtained at 15 dB HL. Conclusions: As the prior generation of cochlear implant recipients ages, the probability of a revision surgery for various causes increases. Cochlear implant surgeons should be aware of the potential pitfalls associated in these often challenging cases.

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Cystic Cochleovestibular Malformation (Incomplete Partition Type 1)

Philippine Journal of Otolaryngology Head and Neck Surgery ◽

10.32412/pjohns.v25i1.663 ◽

2010 ◽

Vol 25 (1) ◽

pp. 41-42 ◽

Cited By ~ 1

Author(s):

Nathaniel W. Yang

Keyword(s):

Hearing Loss ◽

Inner Ear ◽

Temporal Bone ◽

Cochlear Implantation ◽

Type I ◽

Profound Hearing Loss ◽

Increased Risk ◽

Ear Malformations ◽

Temporal Bone Imaging ◽

Incomplete Partition

A 5-year old female with bilateral profound hearing loss underwent computerized tomographic imaging of the temporal bone as part of the work-up to determine the etiology of her deafness, and to delineate middle and inner ear anatomy prior to cochlear implantation. The examination revealed an inner ear malformation which, based on the newest classification of cochleovestibular malformations by Sennaroglu and Saatci, is called an incomplete partition type I (IP-1) or cystic cochleovestibular malformation. This condition is characterized by (1) a cochlea that is lacking the entire modiolus and cribriform area, resulting in a cystic appearance, and (2) a large cystic vestibule.1 Temporal bone imaging is among the most useful examinations in the etiological investigation of idiopathic sensorineural hearing loss in children, with up to 30%2 of the imaging studies showing an abnormality. The detection of inner ear malformations is important, as some abnormalities are associated with an increased risk of meningitis or progressive hearing loss following head trauma.3 Likewise, the approach to cochlear implantation may be influenced by the type of malformation. In this particular patient, the use of a cochlear implant with a full-band electrode design may be more appropriate, as the location of the neural elements within the cystic cochlea is not definitely known.

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Heat-Etching with a Bullivant Type II Simple Freeze-Cleave Device

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100067522 ◽

1970 ◽

Vol 28 ◽

pp. 106-107 ◽

Cited By ~ 1

Author(s):

Ronald S. Weinstein ◽

N. Scott McNutt

Keyword(s):

New Zealand ◽

General Hospital ◽

Massachusetts General Hospital ◽

Type I ◽

Type Ii ◽

Collaborative Effort ◽

Temperature And Pressure ◽

The University

The Type I simple cold block device was described by Bullivant and Ames in 1966 and represented the product of the first successful effort to simplify the equipment required to do sophisticated freeze-cleave techniques. Bullivant, Weinstein and Someda described the Type II device which is a modification of the Type I device and was developed as a collaborative effort at the Massachusetts General Hospital and the University of Auckland, New Zealand. The modifications reduced specimen contamination and provided controlled specimen warming for heat-etching of fracture faces. We have now tested the Mass. General Hospital version of the Type II device (called the “Type II-MGH device”) on a wide variety of biological specimens and have established temperature and pressure curves for routine heat-etching with the device.

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Labelling of non-A, non-B hepatitis infected chimpanzee hepatocytes with nuclease-gold conjugates

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100111367 ◽

1984 ◽

Vol 42 ◽

pp. 250-251

Author(s):

G. D. Gagne ◽

M. F. Miller ◽

D. A. Peterson

Keyword(s):

Endoplasmic Reticulum ◽

Experimental Infection ◽

Uranyl Acetate ◽

Type I ◽

Cellular Injury ◽

Type Ii ◽

Tubular Structures ◽

Type Iii ◽

Type Iv ◽

Infected Chimpanzee

Experimental infection of chimpanzees with non-A, non-B hepatitis (NANB) or with delta agent hepatitis results in the appearance of characteristic cytoplasmic alterations in the hepatocytes. These alterations include spongelike inclusions (Type I), attached convoluted membranes (Type II), tubular structures (Type III), and microtubular aggregates (Type IV) (Fig. 1). Type I, II and III structures are, by association, believed to be derived from endoplasmic reticulum and may be morphogenetically related. Type IV structures are generally observed free in the cytoplasm but sometimes in the vicinity of type III structures. It is not known whether these structures are somehow involved in the replication and/or assembly of the putative NANB virus or whether they are simply nonspecific responses to cellular injury. When treated with uranyl acetate, type I, II and III structures stain intensely as if they might contain nucleic acids. If these structures do correspond to intermediates in the replication of a virus, one might expect them to contain DNA or RNA and the present study was undertaken to explore this possibility.

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Comparative surface and ultrastructural views of methylotrophic bacteria by TEM, STEM, SE, and freeze-etch electron microscopy.

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100128274 ◽

1987 ◽

Vol 45 ◽

pp. 792-793

Author(s):

T.A. Fassel ◽

M.J. Schaller ◽

M.E. Lidstrom ◽

C.C. Remsen

Keyword(s):

Cytoplasmic Membrane ◽

Structural Features ◽

Methylotrophic Bacteria ◽

Type I ◽

Type Ii ◽

Membrane Complex ◽

Oxidation Of Methane ◽

Methane Oxidizing Bacteria ◽

Wall Structures ◽

Methylomonas Albus

Methylotrophic bacteria play an Important role in the environment in the oxidation of methane and methanol. Extensive intracytoplasmic membranes (ICM) have been associated with the oxidation processes in methylotrophs and chemolithotrophic bacteria. Classification on the basis of ICM arrangement distinguishes 2 types of methylotrophs. Bundles or vesicular stacks of ICM located away from the cytoplasmic membrane and extending into the cytoplasm are present in Type I methylotrophs. In Type II methylotrophs, the ICM form pairs of peripheral membranes located parallel to the cytoplasmic membrane. Complex cell wall structures of tightly packed cup-shaped subunits have been described in strains of marine and freshwater phototrophic sulfur bacteria and several strains of methane oxidizing bacteria. We examined the ultrastructure of the methylotrophs with particular view of the ICM and surface structural features, between representatives of the Type I Methylomonas albus (BG8), and Type II Methylosinus trichosporium (OB-36).

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