Hirobumi Watanabe

• Ph.D. in Neuroscience
• Research Associate at Columbia University

The cochlea, or inner ear, is a space fully enclosed within the temporal bone of the skull, except for two membrane-covered portals connecting it to the middle ear space. One of these portals is the round window, which is covered by the Round Window Membrane (RWM). A longstanding clinical goal is to reliably and precisely deliver therapeutics into...

Measurements of perilymph hydrodynamics in the human cochlea are scarce, being mostly limited to the fluid pressure at the basal or apical turn of the scalae vestibuli and tympani. Indeed, measurements of fluid pressure or volumetric flow rate have only been reported in animal models. In this study we imaged the human ear at 6.7 and 3-µm resolution...

Precision medicine for inner-ear disease is hampered by the absence of a methodology to sample inner-ear fluid atraumatically. The round window membrane (RWM) is an attractive portal for accessing cochlear fluids as it heals spontaneously. In this study, we report on the development of a microneedle for perilymph sampling that minimizes the size of...

Background: The round window membrane (RWM) has become the preferred route, over cochleostomy, for the introduction of cochlear implant electrodes as it minimizes inner ear trauma. However, in the absence of a tool designed for creating precise perforation, current practices lead to tearing of the RWM and significant intracochlear pressure fluctua...

The round window membrane (RWM) is the terminal boundary between the fluid-filled inner ear and air-filled middle ear where the sound wave is released from the inner ear after exciting the neuronal sound transducers in the basilar membrane. For the treatment of inner ear diseases, the RWM is an attractive entrance to introduce therapeutic reagents...

Hypothesis: Silver-plated microneedles can be used to confirm penetration of semi-permeable membranes such as the round window membrane (RWM) by detection of voltage change at the moment of perforation. Background: The introduction of microperforations in the RWM can significantly enhance intracochlear delivery of therapeutics. However, the mome...

Hypothesis: Introduction of microperforations in round window membrane (RWM) will allow reliable and predictable intracochlear delivery of pharmaceutical, molecular, or cellular therapeutic agents. Background: Reliable delivery of medications into the inner ear remains a formidable challenge. The RWM is an attractive target for intracochlear del...

A growing number of minimally invasive surgical and diagnostic procedures require the insertion of an optical, mechanical, or electronic device in narrow spaces inside a human body. In such procedures, precise motion control is essential to avoid damage to the patient's tissues and/or the device itself. A typical example is the insertion of a cochl...

A growing number of minimally invasive surgical and diagnostic procedures require the insertion of an optical, mechanical, or electronic device in narrow spaces inside a human body. In such procedures, precise motion control is essential to avoid damage to the patient's tissues and/or the device itself. A typical example is the insertion of a cochl...

The round window membrane (RWM) is increasingly becoming a target for amplification using active middle ear implants. However, the current strategy of using available transducer tips may have negative consequences for the RWM. We investigated the microanatomy of the RWM to establish a basis for the design of the transducer tip for the RWM driver. U...

A cochlear implant device includes a deformable and stretchable flexible strip composed of a biological compatible material and positioned about a longitudinal axis so as to form a spiral. The implant device has a plurality of conductive strips with electrode windows formed so as to expose a segment of each conductive strip. A density of the electr...

A minimally invasive electrical recording and stimulating technique capable of simultaneously monitoring the activity of a significant number (e.g., 10(3) to 10(4)) of neurons is an absolute prerequisite in developing an effective brain-machine interface. Although there are many excellent methodologies for recording single or multiple neurons, ther...

A crucial factor limiting the adoption of brain-machine interfaces is the invasiveness of conventionally implanted cortical microelectrode arrays. Recently, Llinás et al. proposed a new, less invasive type of multielectrode neural recording, using sub-micrometer insulated nanowires placed in the capillary bed of the central nervous system [1]. Init...