This page contains a Flash digital edition of a book.
Update on the Surgical Management of Craniopharyngiomas


Table 1: Operative Approaches Advantages


Anterior Midline Trans-sphenoidal


Subfrontal Decreased risk of visual injury Straight frontal trajectory;


can access third ventricle through lamina terminalis


Anterolateral Pterional


Access to suprasellar cistern, even with pre-fixed chiasm


Orbitozygomatic


Disadvantages Difficult in children with a


non-pneumatised sinus; higher risk of CSF leak


Potential violation of frontal sinus; technically more difficult with a pre-fixed chiasm


Grade III and IV tumours


Indications Grade I and II tumours


Limited view of contralateral opticocarotid Can be used for intrasellar, suprasellar, triangle and contralateral retrocarotid


space; posterior third ventricle obscured by ipsilateral hypothalamus


Increased access to the posterior clinoid, Same as pterional basilar apex and suprasellar region;


improved manoeuvrability of surgical instruments to these regions


Transpetrosal


Allows for visualisation and wide exposure of retrochiasmatic tumours


Intraventricular Transcallosal and transventricular Transcortical and transventricular


Translamina terminalis


Combined Approaches Subtemporal and transpetrosal


Pterional and


transcallosal Subfrontal and pterional


CSF = cerebrospinal fluid.


subdiaphragmatic) tumours because it allows access to the sellar and suprasellar regions with a decreased risk of visual injury. Disadvantages include that it may be difficult in young children with a non-pneumatised sphenoid sinus and the approach carries a higher risk of CSF leak. The subfrontal approach is most appropriate for grade III and IV suprasellar tumours. This approach allows for a straight frontal trajectory with direct access to the anterior third ventricle through the lamina terminalis7 pre-chiasmatic dissection of the tumour.


and enables


Case series examining this approach have demonstrated that, regardless of size, at least 90% of all craniopharyngiomas can be removed using the subfrontal and pterional approaches.1,6,10,13 Potential complications of the subfrontal approach include the risk of potential violation of the frontal sinus as well as damage to the olfactory tract. In addition, this approach may be technically more complicated in the presence of a pre-fixed chiasm, although this is not an absolute contraindication to the use of the subfrontal approach.


Anterolateral Approach


The pterional approach is often used in craniopharyngioma resection due to its advantages in accessing the suprasellar cistern,


EUROPEAN NEUROLOGICAL REVIEW


facilitating the resection of intrasellar, suprasellar, pre-chiasmatic and retrochiasmatic tumours.7,13


and the ipsilateral


hypothalamic wall makes visualisation of the posterior third ventricle across the lamina terminalis especially difficult.4


The orbitozygomatic approach expands on the pterional approach with the addition of removal of the supraorbital rim, zygomatic arch or both, thus increasing access to the posterior clinoid, basilar apex and suprasellar region and improved manoeuvrability of surgical instruments to these regions.7,22–24


This approach is useful for lesions


with significant suprasellar extension. Transpetrosal Approach


The resection of large retrochiasmatic craniopharyngiomas is facilitated by the anteriorly and superiorly oriented surgical corridor made possible by this approach. Conventional anterior approaches carry a risk of injury to the anterior perforators that supply the hypothalamus and chiasm. Injury to the hypothalamus and optic pathways can be minimised by mobilisation of the sigmoid sinus medially, allowing for dissection of a retrochiasmatic tumour under direct visualisation.25,26


109


Increased visualisation of lateral tumour, particularly within Sylvian fissure


Retrochiasmatic, unilateral


tumours extending to posterior fossa along clivus


Large craniopharyngioma Tumours with greater lateral extent


Dependent on dilated foramen of Monroe


Lower risk of retraction injury than transcallosal approach


Lower risk to anterior perforators than subfrontal approach


Retraction injury


Violation of cortex and increased risk of post-operative seizures


Large retrochiasmatic tumours


Same as pterional; especially useful for tumours with significant suprasellar extension


pre-chiasmatic and retrochiasmatic tumours


Intraventricular tumours


Cases with large ventricles with tumour extending to dorsal surface of brain


This approach has significant


disadvantages; a restricted view of the contralateral opticocarotid triangle, the contralateral retrocarotid space11


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64  |  Page 65  |  Page 66  |  Page 67  |  Page 68  |  Page 69  |  Page 70  |  Page 71  |  Page 72  |  Page 73  |  Page 74  |  Page 75  |  Page 76  |  Page 77  |  Page 78  |  Page 79  |  Page 80  |  Page 81  |  Page 82  |  Page 83  |  Page 84  |  Page 85  |  Page 86  |  Page 87  |  Page 88  |  Page 89  |  Page 90  |  Page 91  |  Page 92  |  Page 93  |  Page 94  |  Page 95  |  Page 96  |  Page 97  |  Page 98  |  Page 99  |  Page 100  |  Page 101  |  Page 102  |  Page 103  |  Page 104  |  Page 105  |  Page 106  |  Page 107  |  Page 108  |  Page 109  |  Page 110  |  Page 111  |  Page 112  |  Page 113  |  Page 114  |  Page 115  |  Page 116
Produced with Yudu - www.yudu.com