Mukherji SK, consulting ed. Chong VFH, guest ed. Neuroimaging Clinics of North America: Skull Base and Temporal Bone Imaging. Vol 19, No 3, August 2009. The clinics.com, pages 287-516, $293.00
The August 2009 issue of the Neuroimaging Clinics of North America edited by Dr. Chong from Singapore is a well written and well illustrated contribution to this ongoing series of neuroradiology publications. Eleven chapters (29 authors) are contained in this timely book: “Imaging of Hearing Loss,” “Imaging of Mastoid, Middle Ear and IAC after Surgery,” “Imaging of Inflammatory and Infectious Disease in the Temporal Bone,” “Imaging of Temporal Bone Tumors,” “Petrous Apex,” “Imaging of the Cerebellopontine Angle,” “Imaging of the Facial Nerve,” “Imaging of the Anterior Skull Base,” “Imaging of the Central Skull Base,” “Imaging of Jugular Foramen,” and “Imaging of Craniovertebral Junction.”
In the initial chapter, the authors nicely summarize and demonstrate the CT and MR findings in hearing loss (conductive, neurosensory, mixed) in both congenital and acquired types of hearing loss. Images and explanations worth reviewing include the persistent stapedial artery, ossicular fixation to the epity mpanum, tympanoselerosis fenestral otospongiosis, labyrinthine dysplasia, intra- labyrinthine Schwannoma, vestibulcochlear neuritis, among others. There is a particularly good summary of congenital causes of hearing less.
As in most imaging evaluations of the head and neck, assessing the post operative patient is difficult. Clarifying some of the approaches can be found in the second chapter indicating “what every radiologist should know’. In that chapter, the various surgical procedures/exposures are shown. Many of the appearances and what was done surgically is probably unfamiliar to most neuroradiologists unless they are in a practice with an active temporal bone surgeon. Key items in this chapter include the terminology used by otologic surgeons and what they are looking for specifically in the post operative temporal bone.
Inflammatory and infectious diseases of the temporal bone are the most common indications for CT imaging of this area. Aside from the commonly encountered cholesteatoma and inflammatory debris, seldom seen abnormalities are shown, such as calcifications of stapedial crura, bomy ridge at the origin of the malleal ligament, restricted diffusion in cholesteatoma, and suggestions on how DWI could be useful in some cases. The authors deal with inflammation in a segmental anatomic fashion so after middle ear abnormalities, descriptions of labyrinthine inflammations follow with a nice review of the relatively subtle MR findings. A review of enhancement patterns of the facial nerve serve to reinforce the concept of what portions of the facial nerve are expected to enhance.
“Imaging of Temporal Bone Tumors” and an imaging evaluation of the petrous apex are the next two chapters. Some important points are demonstrated such as distinguishing a small congenital cholesteatoma from a glomus tympanicum using DWI. Some legends needed clarification; for example, in a case where a diagnosis of a tumor at the level of the jugular bulb was mistakenly made by both the radiologists and neurosurgeons, the imaging that caused it to be reclassified as normal is never shown nor is there a discussion on how this particular case was resolved. There are excellent images which again reinforce the appearance of the seldom encountered tumors: facial nerve Schwannoma at the geniculate ganglion level, Ewing’s sarcoma of the temporal bone, LCH, mets to the facial nerve, congenital cholestestoma, and many more. What particularly is appealing about this chapter (and others, for that matter) are the excellent and detailed images with precisely placed labels.
Following on the heels of chapters dealing with temporal bone tumors and infections, the following chapters (see above for listing) maintain the high image quality with substantial discussion and legends. There is, as one might expect, an overlap of information in different chapters — for instance, showing cholesteomas both in the inflammatory temporal bone chapter and in the one dealing with facial nerve imaging; the same applies to tumors of the temporal bone and Schwannomas appearing also in the chapter dealing with the facial nerve. This repetition is good and serves to reinforce imaging concepts.
The Editor has nicely put together three chapters in the latter part of the book — “Imaging of the Anterior Skull Base,” “Imaging of the Central Skull Base,” and “Imaging of Jugular Foramen.” Somehow completely uninterpretable CT images, said to be bone windows, of a sphenoid lesion were included in the Central Skull Base chapter. How that made it into the book is mysterious. The last chapter deals very well with the craniovertebral junction, re-emphasizing and clarifying concepts of pathology in this area.
This is a well thought out edition of the clinics; in fact, to this reviewer, it is one of the best of the series of NICA. It addresses common/uncommon diseases of the temporal bone and does so with quality images. It is a highly recommended purchase.
