Further Reading

Anterior Craniofacial Resection

Cantù G, Solero CL, Mariani L, Salvatori P, Mattavelli F, Pizzi N, Riggio E (1999) Anterior craniofacial resection for malignant ethmoid tumors–a series of 91 patients. Head Neck 21(3):185–191

Cantù G, Riccio S, Bimbi G, Squadrelli M, Colombo S, Compan A, Rossi M, Pompilio M, Solero CL (2006) Craniofacial resection for malignant tumours involving the anterior skull base. Eur Arch Otorhinolaryngol 263(7):647–652

Langstein HN, Chang DW, Robb GL (2001) Coverage of skull base defects. Clin Plast Surg 28(2):375–387, x Moyer JS, Chepeha DB, Teknos TN (2004) Contemporary

skull base reconstruction. Curr Opin Otolaryngol Head Neck Surg 12(4):294–299

Pitman KT, Costantino PD, Lassen LF (1995) Sinonasal undifferentiated carcinoma: current trends in treatment. Skull Base Surg 5(4):269–272

Scher RL, Cantrell RW (1992) Anterior skull base reconstruction with the pericranial flap after craniofacial resection. Ear Nose Throat J 71(5):210–212, 215–217 Schuster JJ, Phillips CD, Levine PA. MR of esthesioneuroblastoma (olfactory neuroblastoma) and appearance after craniofacial resection. AJNR Am J Neuroradiol

1994;15(6):1169–1177.

Decompression of Cystic Sellar/

Suprasellar Lesions

al-Wahhabi B, Choudhury AR, al-Moutaery KR, Aabed M, Faqeeh A (1993) Giant craniopharyngioma with blindness reversed by surgery. Childs Nerv Syst 9(5):292–294 Ohmori K, Collins J, Fukushima T (2007) Craniopharyngiomas in children. Pediatr Neurosurg

43(4):265–278

Transsphenoidal Resection

Bonneville F, Cattin F, Marsot-Dupuch K, Dormont D, Bonneville JF, Chiras J (2006) T1 signal hyperintensity in the sellar region: spectrum of findings. Radiographics 26(1):93–113

Kremer P, Forsting M, Ranaei G, Wüster C, Hamer J, Sartor K, Kunze S (2002) Magnetic resonance imaging after transsphenoidal surgery of clinically non-­ functional pituitary macroadenomas and its impact on detecting residual adenoma. Acta Neurochir 144(5):433–443

Rajaraman V, Schulder M (1999) Postoperative MRI appearance after transsphenoidal pituitary tumor resection. Surg Neurol 52(6):592–598; discussion 598–599

Romano A, Chibbaro S, Marsella M, Oretti G, Spiriev T, Iaccarino C, Servadei F (2010) Combined endoscopic transsphenoidal-transventricular approach for resection of a giant pituitary macroadenoma. World Neurosurg 74(1):161–164

Steiner E, Knosp E, Herold CJ, Kramer J, Stiglbauer R, Staniszewski K, Imhof H (1992) Pituitary adenomas: findings of postoperative MR imaging. Radiology 185(2):521–527

Yoon PH, Kim DI, Jeon P, Lee SI, Lee SK, Kim SH (2001) Pituitary adenomas: early postoperative MR imaging after transsphenoidal resection. AJNR Am J Neuroradiol 22(6): 1097–1104

Transsphenoidal Resection

Complications

Ahmad FU, Pandey P, Mahapatra AK (2005) Post operative ‘pituitary apoplexy’ in giant pituitary adenomas: a series of cases. Neurol India 53(3):326–328

Bonneville F, Cattin F, Marsot-Dupuch K, Dormont D, Bonneville JF, Chiras J (2006) T1 signal hyperintensity in the sellar region: spectrum of findings. Radiographics 26(1):93–113

Buchinsky FJ, Gennarelli TA, Strome SE, Deschler DG, Hayden RE (2001) Sphenoid sinus mucocele: a rare complication of transsphenoidal hypophysectomy. Ear Nose Throat J 80:886–888

Cappabianca P, Cavallo LM, Colao A, de Divitiis E. Surgical complications associated with the endoscopic endonasal transsphenoidal approach for pituitary adenomas. J Neurosurg. 2002;97(2):293–298.

Connor SE (2010) Imaging of skull-base cephalocoeles and cerebrospinal fluid leaks. Clin Radiol 65(10): 832–841 Crowley RW, Dumont AS, Jane JA Jr (2009) Bilateral intracavernous carotid artery pseudoaneurysms as a result of sellar reconstruction during the transsphenoidal­ resection of a pituitary macroadenoma: case report.

Minim Invasive Neurosurg 52(1):44–48

Goel A, Deogaonkar M, Desai K (1995) Fatal postoperative ‘pituitary apoplexy’: its cause and management. Br J Neurosurg 9(1):37–40

Hald JK, Nakstad PH, Kollevold T, Bakke SJ, Skalpe IO (1992) MR imaging of pituitary macroadenomas before and after transsphenoidal surgery. Acta Radiol 33(5):396–399

Kadyrov NA, Friedman JA, Nichols DA, Cohen-Gadol AA, Link MJ, Piepgras DG (2002) Endovascular treatment of an internal carotid artery pseudoaneurysm following transsphenoidal surgery. Case report J Neurosurg 96(3):624–627

Kessler L, Legaludec V, Dietemann JL, Maitrot D, Pinget M (1999) Sphenoidal sinus mucocele after transsphenoidal surgery for acromegaly. Neurosurg Rev 22(4): 222–225 La Fata V, McLean N, Wise SK, DelGaudio JM, Hudgins PA (2008) CSF leaks: correlation of high-resolution CT and multiplanar reformations with intraoperative

endoscopic findings. AJNR Am J Neuroradiol 29(3): 536–541

Lloyd KM, DelGaudio JM, Hudgins PA (2008) Imaging of skull base cerebrospinal fluid leaks in adults. Radiology 248(3):725–736

Puri AS, Zada G, Zarzour H, Laws E, Frerichs K (2012) Cerebral vasospasm after transsphenoidal resection of pituitary adenomas: report of 3 cases and review of the literature. Neurosurgery 71:173–180

Raymond J, Hardy J, Czepko R, Roy D (1997) Arterial injuries in transsphenoidal surgery for pituitary adenoma; the role of angiography and endovascular treatment. AJNR Am J Neuroradiol 18(4):655–665

Saeki N, Hoshi S, Sunada S, Sunami K, Murai H, Kubota M, Tatsuno I, Iuchi T, Yamaura A (2002) Correlation of high signal intensity of the pituitary stalk in macroadenoma and postoperative diabetes insipidus. AJNR Am J Neuroradiol 23(5):822–827

Steiner E, Knosp E, Herold CJ, Kramer J, Stiglbauer R, Staniszewski K, Imhof H (1992) Pituitary adenomas: findings of postoperative MR imaging. Radiology 185(2):521–527

Steiner E, Math G, Knosp E, Mostbeck G, Kramer J, Herold CJ (1994) MR-appearance of the pituitary gland before and after resection of pituitary macroadenomas. Clin Radiol 49(8):524–530

Taylor SL, Tyrrell JB, Wilson CB (1995) Delayed onset of hyponatremia after transsphenoidal surgery for pituitary adenomas. Neurosurgery 37(4):649–653; discussion 653–654

van Aken MO, de Marie S, van der Lely AJ, Singh R, van den Berge JH, Poublon RM, Fokkens WJ, Lamberts SW, de Herder WW. Risk factors for meningitis after transsphenoidal surgery. Clin Infect Dis 1997 Oct;25(4):852–856.

Yoon PH, Kim DI, Jeon P, Lee SI, Lee SK, Kim SH (2001) Pituitary adenomas: early postoperative MR imaging after transsphenoidal resection. AJNR Am J Neuroradiol 22(6):1097–1104

Zada G, Du R, Laws ER Jr (2011) Defining the “edge of the envelope”: patient selection in treating complex sellar-based neoplasms via transsphenoidal versus open craniotomy. J Neurosurg 114(2):286–300

Zona G, Testa V, Sbaffi PF, Spaziante R (2002) Transsphenoidal treatment of empty sella by means of a silastic coil: technical note. Neurosurgery 51(5): 1299–1303; discussion 1303

Lipira A, Limbrick D, Haughey B, Custer P, Chicoine MR (2009) Titanium mesh reconstruction to maintain scalp contour after temporalis musculofascial flap reconstruction of the floor of the middle cranial fossa: a technical note and report of two cases. Skull Base 19(4):303–309

Surgical Approaches for Vestibular Schwannoma Resection

Friedman RA, Goddard JC, Wilkinson EP, Schwartz MS, Slattery WH 3rd, Fayad JN, Brackmann DE (2011) Hearing preservation with the middle cranial fossa approach for neuro fibromatosis type 2. Otol Neurotol 32:1530–1537

Silk PS, Lane JI, Driscoll CL (2009) Surgical approaches to vestibular schwannomas: what the radiologist needs to know. Radiographics 29(7):1955–1970

Bennett ML, Jackson CG, Kaufmann R, Warren F (2008) Postoperative imaging of vestibular schwannomas. Otolaryngol Head Neck Surg 138(5):667–671

Hwang PH, Jackler RK (1996) Lipoid meningitis due to aseptic necrosis of a free fat graft placed during neurotologic surgery. Laryngoscope 106(12 Pt 1):1482–1486

Schmerber S, Palombi O, Boubagra K, Charachon R, Chirossel JP, Gay E (2005) Long-term control of vestibular schwannoma after a translabyrinthine complete removal. Neurosurgery 57(4):693–698

Weissman JL, Hirsch BE, Fukui MB, Rudy TE (1997) The evolving MR appearance of structures in the internal auditory canal after removal of an acoustic neuroma. AJNR Am J Neuroradiol 18(2):313–323

Miller RS, Pensak ML (2006) An anatomic and radiologic evaluation of access to the lateral internal auditory canal via the retrosigmoid approach and description of an internal labyrinthectomy. Otol Neurotol 27(5):697–704

Silk PS, Lane JI, Driscoll CL (2009) Surgical approaches to vestibular schwannomas: what the radiologist needs to know. Radiographics 29(7):1955–1970

Radiosurgery for Vestibular

Schwannomas

Middle Cranial Fossa Reconstruction

Chang DW, Langstein HN, Gupta A, De Monte F, Do KA, Wang X, Robb G (2001) Reconstructive management of cranial base defects after tumor ablation. Plast Reconstr Surg 107(6):1346–1355; discussion 1356–1357

Jacobsen N, Mills R (2006) Management of stenosis and acquired atresia of the external auditory meatus. J Laryngol Otol 120(4):266–271

Meijer OW, Weijmans EJ, Knol DL, Slotman BJ, Barkhof F, Vandertop WP, Castelijns JA (2008) Tumor-volume changes after radiosurgery for vestibular schwannoma: implications for follow-up MR imaging protocol. AJNR Am J Neuroradiol 29(5):906–910

Nakamura H, Jokura H, Takahashi K, Boku N, Akabane A, Yoshimoto T (2000) Serial follow-up MR imaging after gamma knife radiosurgery for vestibular schwannoma. AJNR Am J Neuroradiol 21(8):1540–1546

8.1\ Osseointegrated Bone

Conduction Hearing

Implants

8.1.1\ Discussion

Osseointegrated bone conduction hearing implants (BAHA, Cochlear Corporation, Australia and Ponto, Oticon Corporation, Sweden) are implantable hearing devices used in patients with conductive, mixed, or unilateral sensorineural hearing loss who cannot wear traditional air-conducting hearing aids. These devices function in conductive hearing loss by direct transmission of sound via bone conduction to the ipsilateral inner ear, bypassing the external auditory canal and middle ear. In unilateral profound sensorineural hearing loss, they work by

D.T. Ginat, M.D., M.S. (*)

Department of Radiology, University of Chicago, Chicago, IL, USA

e-mail: dtg1@uchicago.edu

G. Moonis, M.D.

Department of Radiology, Columbia Presbyterian, New York, NY, USA

S.K. Mukherji, M.D., M.B.A., F.A.C.R.

Department of Radiology, Michigan State University, East Lansing, MI, USA

M.B. Gluth, M.D.

Department of Surgery, Division of Otolaryngology, University of Chicago, Chicago, IL, USA

transcranial bone conduction of sound to the contralateral normal functioning cochlea.

The traditional forms of these devices consist of a titanium screw-like implants anchored into the squamous portion of the temporal bone, as well as percutaneous external flange fixture abutments to which removable sound processors/vibrators will attach. However, in newer versions, these devices may lack a percutaneous component and instead feature a magnetic disk that is attached to the osseointegrated screw completely contained just under the scalp (BAHA Attract, Cochlear Corporation, Australia), working via transcutaneous passage of sound vibration. All of these osseointegrated hearing implants can be identified on imaging with a typical implant depth of 3–4 mm into the cortex of the skull (Fig. 8.1). However, the magnetic component of newer non-percutane- ous versions will generate a lot of imaging ­artifact. All osseointegrated hearing implants that have been approved for use in the USA are MRI compatible when the external sound processor is removed. The most common complication of these devices is adjacent soft tissue and skin reactions resulting in cellulitis or infection. Other complications include loss of osseointegration due to adjacent bone necrosis which can result in screw loosening and extrusion. Intracranial abscess has also been reported, but this is a rare complication of BAHA implantation.

Fig. 8.1  The patient has a history of conductive hearing loss due to aural atresia. Lateral scout image (a) shows the BAHA device in position (arrow). Axial CT image (b) shows the screw embedded in the temporal bone (arrow)

and the overlying abutment (arrowhead). Photograph of BAHA device components (c) (Courtesy of Cochlear Corp)