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2021 ◽  
Author(s):  
Kadir Erkmen ◽  
Emad Aboud ◽  
Ossama Al-Mefty

Abstract Microsurgical resection of craniopharyngiomas poses significant challenges, which are amplified with tumors in the retrochiasmatic location and larger size. Traditional pterional trans-sylvian, subfrontal translamia terminalis, or interhemispheric approaches provide narrow surgical corridors with obstructed visualization of the tumor by the prefixed chiasm and slit optic carotid window.1–5 The superior extension of the tumor compressing the hypothalamus and third ventricle are likewise inaccessible. Dissection through these approaches requires crossing and manipulation of the already compromised optic apparatus with surgical instruments. Finally, the basilar artery and its perforating branches are often adherent to the posterior aspect of the tumor, and are invisible.  Endonasal endoscopic techniques have been utilized as a surgical approach that accesses the tumor without crossing the optic apparatus; however, these approaches have a significant risk of cerebrospinal fluid leakage and require dissection of the basilar artery and hypothalamus from long distances with lengthy instruments.6–9 Frequently, the surgeon achieves only partial removal.  The petrosal approach is ideal for tumors in the retrochiasmatic location.10–13 Advantages include unhindered access to the retrochiasmatic space without crossing the optic nerve and chiasm. The angle of approach allows visualization superiorly to the hypothalamus. Additionally, the approach shortens the distance to the tumor, allowing for delicate bimanual dissection of the tumor, especially at the basilar artery and hypothalamic interfaces.  This video demonstrates three cases of retrochiasmatic craniopharyngioma resection through the petrosal approach, highlighting these advantages to optimize patient outcome. The patients and guardians consented for the surgery, photography, and publication of the patient's image.  Figures from Al-Mefty et al11 used with permission from the Journal of Neurosurgery Publishing Group.  Additional figures republished from Al-Mefty et al.12 “The petrosal approach for the resection of retrochiasmatic craniopharyngiomas,” Neurosurgery, 2008, volume 62, issue 5 Suppl 2 (ONS), ONS331-ONS336, by permission of the Congress of Neurological Surgeons.


2019 ◽  
Author(s):  
Qazi Zeeshan ◽  
Juan P Carrasco Hernandez ◽  
Nina T Yoh ◽  
Laligam N Sekhar

Abstract This two-dimensional video shows the technical nuances of complete microsurgical resection of a hypothalamic craniopharyngioma located in the retrochiasmatic region by the transpetrosal approach.  This 49-yr-old man presented with progressive fatigue, excessive sleepiness, and difficulty in vision in both eyes. He was found to have right CN 3 paralysis and bitemporal hemianopsia on neurological examination. Further workup revealed panhypopituitarism. Brain magnetic resonance imaging (MRI) demonstrated a large solid retrochiasmatic hypothalamic lesion with homogeneous contrast enhancement, measuring 2.1 × 2.6 × 2.4 cm. Optic chiasm was prefixed, and the tumor was just posterior to the pituitary stalk area. The preoperative differential diagnosis included hypothalamic astrocytoma, craniopharyngioma, germinoma, and histiocytosis. Because of the prefixed chiasm, a presigmoid, transpetrosal approach was performed. Our initial plan was a large biopsy, but based on frozen section histology, we decided to excise the tumor completely. The tumor had a pseudocapsule, which was firm and yellowish. It was debulked, dissected from the surrounding hypothalamus, and removed completely. The pituitary stalk was found at the anterior and inferior ends of the tumor and was preserved.  Postoperatively, the patient developed diabetes insipidus and requires desmopressin replacement, which was gradually tapered. For panhypopituitarism, he is receiving thyroxine, hydrocortisone, and testosterone.  Postoperatively, patient had an improvement in vision in his left eye and ptosis was improving in the right eye with mRs 1- at 10-wk follow-up.  An informed consent was obtained from the patient prior to the surgery, which included videotaping of the procedure and its distribution for educational purposes. All relevant patient identifiers have also been removed from the video and accompanying radiology slides.


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