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Background The lateral extended transsphenoidal endoscopic approach (LETEA) is used to remove tumors located lateral to the cavernous segment of the internal carotid artery under direct visual control and provides access to Meckel cave, pterygopalatine fossa, medial part of the middle cranial fossa, and orbit. We describe an extended transsphenoidal approach to the amygdalohippocampectomy through the pterygopalatine fossa. Methods The LETEA to the middle cranial fossa through the pterygopalatine fossa was studied on 3 injected human cadavers at the Burdenko Neurosurgery Institute in Moscow, Russia. Results LETEA and trepanation of the greater wing of the sphenoid bone allow access to the medial part of the middle cranial fossa. Medial segments of the temporal lobe (hippocampus and amygdala) and the temporal pole were removed under guidance of the 45° angled endoscope. Conclusions LETEA through the pterygopalatine fossa is minimally invasive and provides direct access to the temporal pole and medial part of the temporal lobe. This approach may reduce risk of neurologic deficit and help to avoid cosmetic defects in the frontotemporal region associated with injury to temporal muscle and facial nerve injury as can occur during transcranial approaches. Disadvantages that limit application of LETEA include risk of cerebrospinal fluid leak and skills needed for manipulation in a narrow and deep surgical field with angled 30° and 45° endoscopes.

Background Despite the rarity of epidermoid cysts in the chiasmatic region, their surgical treatment is particularly complicated because of the tendency toward massive dissemination of the epidermoid masses along cerebrospinal fluid pathways and significant deviation of the tumor from the midline. Objective The purpose of the present work is evaluation of the role of extended transsphenoidal endoscopic endonasal approaches in the surgery of epidermoid cysts. Methods The study included 6 patients with epidermoid cysts in the chiasmatic region who were operated on at the Burdenko Neurosurgery Institute in the last 5 years using an anterior extended transsphenoidal endoscopic endonasal approach. Results The epidermoid masses were totally removed in 5 patients, but in no patient was it possible to completely remove the epidermoid cyst capsule. Visual deterioration was not noted in any patient, nor did new focal neurologic symptoms appear. One of the patients developed hypopituitary disorders in the postoperative period. No recurrence of the epidermoid cysts was observed during the follow-up period. Conclusions Removal of epidermoid cysts in the chiasmatic region using an anterior extended transsphenoidal endoscopic approach may be an alternative to transcranial microsurgery operations. This technique is widely accepted as an approach to this area.

Objective The endoscopic extended transsphenoidal approach for suprasellar craniopharyngiomas may be a really alternative to the transcranial approach in many cases. The authors present their experience with this technique in 136 patients with craniopharyngiomas. Methods From the past 7 years 204 patients with different purely supradiaphragmatic tumors underwent removal by extended endoscopic transsphenoidal transtuberculum transplanum approach. Most of the patients (136) had craniopharyngiomas (suprasellar, intra-extraventricular). The patients were analyzed according to age, sex, tumor size, growth and tumor structure, and clinical symptoms. Twenty-five patients had undergone a previous surgery. The mean follow-up was 42 months (range, 4–120 months). The operation is always performed with the bilateral endoscopic endonasal anterior extended transsphenoidal approach. Results A gross-total removal was completed in 72%. Improvement of vision or absence of visual deterioration after operation was observed in 89% of patients; 11% had worsening vision after surgery. Endocrine dysfunction did not improve after surgery, new hypotalamopituitary dysfunction (anterior pituitary dysfunction or diabetes insipidus) or worsening of it was observed in 42.6%. Other main complications included transient new mental disorder in 11%, temporary neurological postoperative deficits in 3.7%, bacterial meningitis in 16%, cerebrospinal fluid leaks in 8.8%. The recurrence rate was 20% and the lethality was 5.8%. Conclusions Resection of suprasellar craniopharyngiomas using the extended endoscopic approach is a more effective and less traumatic technology, able to provide resection of the tumor along with high quality of life after surgery, and relatively rare postoperative complications and mortality.

A new approach to segment partitioning for superpixel segmentation is proposed.A new objective function optimized with graph cuts is proposed.The algorithm produces compact and regular superpixels of high quality.Comparable results with contemporary algorithms are achieved. The problem of image segmentation is formulated in terms of recursive partitioning of segments into subsegments by optimizing the proposed objective function via graph cuts. Our approach uses a special normalization of the objective function, which enables the production of a hierarchy of regular superpixels that adhere to image boundaries. To enforce compactness and visual homogeneity of segments a regularization strategy is proposed. Experiments on the Berkeley dataset show that the proposed algorithm is comparable in its performance to the state-of-the-art superpixel methods.

Background and Importance Endodermal cysts are a rare pathology of the central nervous system located mostly in the upper thoracic or cervical regions. Seldomly, the cysts are found intracranially, most often in the subtentorial area (on the ventral surface of the brainstem, pontocerebellar angle, and fourth ventricle). Traditional approaches to the ventral surface of the brainstem are complicated and traumatic, and they do not provide a good view of the tumor's central and contralateral parts. In this case report, we present an alternative approach for resection of the endodermal cyst on the ventral surface of the brainstem. Clinical Presentation Our patient, 27 years old, was observed for 6 years with a preliminary diagnosis of pilocytic astrocytoma. Previously, the patient had an Ommaya system implanted into the cyst and underwent stereotactic radiotherapy (54 Gy). The tumor was resected through an extended transsphenoidal transclival endonasal endoscopic approach. Histologic examination confirmed the diagnosis of endodermal cyst. Significant regression of the symptoms was noted. Complications were not seen. Conclusion The main advantage of the transclival transnasal approach is the direct access to the clivus and ventral surface of the brainstem without traction of the cerebral structures. If the transsphenoidal transclival approach is used, the cranial nerves are out of the approach area that minimizes the risk to damage it. An extended transsphenoidal transclival endonasal endoscopic approach is an alternative to traditional microsurgical approaches to pathologic processes on the ventral surface of the brainstem (cavernomas, endodermal cysts), located centrally.