Anatomical considerations of high jugular bulb in lateral skull base surgery

Abstract

In order to study high jugular bulb management in lateral skull base surgery, an anatomical study was conducted on 30 temporal bones by examining the relationship between the internal auditory canal (IAC) and the jugular bulb. The following parameters were measured: 1) Height of the jugular bulb (H) … distance between the level of the jugular bulb dome and the line passing through the confluence of the sigmoid sinus with the jugular bulb (SS-JB), 2) Mastoid length (ML) … distance between the mastoid process and middle cranial fossa dura, 3) Distance between the most inferior part of the porus acousticus and jugular bulb dome (A), 4) Distance between the porus acousticus and SS-JB (B). The jugular bulb was defined as high when it occupied more than two thirds of (B). The incidence of a high jugular bulb was 23 per cent in this study. When the jugular bulb was high, the mean (H) and (A) were 9.4 ± 1.9 mm and 2.7 ± 0.5 mm, respectively. (H) was higher on the right side than on the left side. No statistically significant difference was found between small and large mastoids (t-test: p>0.05). It was concluded that when a high jugular bulb was encountered during lateral skull base surgery, the jugular bulb position allows a very small working area inferior to the IAC. In these cases, a 3 or 4 mm depression of the jugular bulb is necessary in order to expose the lower cranial nerves. This can be accomplished by lowering the jugular bulb with the technique already described.

Craniofacial measures of chronic otitis media patients by 2D reformatted CT

“…In an earlier report (Turgut and Tos, 1992), pneumatization of the mastoid bone was claimed as a cause of high JB; however, there are also some other researchers (Orr and Todd, 1988;Aslan et al, 1997) who advocate the idea that there is no relation between the position of the JB and pneumatization. In this study, the JB was found to be higher on the right side; however, no statistically significant differences were found between the COM group and the control group regarding the height of the JB.…”

Asterion as a surgical landmark for lateral cranial base approaches

“…This region is often the site of vascular, inflammatory, neoplastic, or traumatic lesions, and surgical or (Zimmerman and Seifert, 1997;Ozveren et al, 2002). In cranial base surgery, the anterior transpetrosal approach offers the possibility of removing invasive petroclival lesions extending into the posterior fossa, the cavernous sinus, and the extradural space around the petrous apex (Aslan et al, 1997;Ozveren et al, 2002;Turgut et al, 2003). It is an indisputable fact that the success in surgical strategy and planning mainly relies on the surgeon's knowledge of the superficial anatomy.…”

“…The asterion, defined as the junction of the lambdoid, parietomastoid, and occipitomastoid sutures, has been advocated as a primary landmark in performing combined petrosal approaches to the cranial base (Williams et al, 1995;Aslan et al, 1997;Day and Tschabitscher, 1998;Aziz et al, 2000). But there has also been some doubt requiring its reliability as a landmark (Yamashima et al, 2004).…”

The partial labyrinthectomy petrous apicectomy approach to petroclival meningiomas. A quantitative anatomic comparison with other approaches to the same region

“…This bony phase and the successive ones are safer in petrous bones with "large" mastoids [≥ 35 mm long, according to Aslan et al 3 ] because it is possible to obtain a wider surgical corridor and a better working burr hole angle. This consideration also holds for Trautmann's triangle.…”