Neurosurgical treatment
tumor, pituitary adenoma, bleeding, postoperative liquorrhea, visual impairment, tamponade, neurological defects, fistula, adenoma, somatotropinomas, tumors
TUMOR, PITUITARY ADENOMA, BLEEDING, SYNDROMES, CAVITY, ADENOMA, TUMORS
Indications for pituitary adenoma surgery were active adenoma growth, visual impairment or other neurological defects, and endocrine syndromes that require medical treatment. The operations were performed by a single team of surgeons trained in microscopic and endoscopic techniques and with significant practical experience in both techniques. The experience of surgeons with microscopic and endoscopic techniques in the present study was comparable. A team of surgeons performed more than 50 operations for each method in the year preceding the study. Preoperative therapy with somatostatin analogues was not carried out because there is currently no evidence that preoperative preparation with somatostatin analogues improves surgical outcomes in patients with somatotropinomas.Adenomectomy was performed using a microsurgical technique with a surgical endoscope or microscope. Group 1 received microscopic transsphenoidal surgery with a Leica M695 D2 surgical microscope (Leica, Switzerland) via the Hirsch approach. The patient was placed in a semi-sitting position, and the lateral skull base images were obtained using an electron-optical converter (EOP) installed perpendicular to the sagittal projection of the skull. Before surgery, patients underwent either the lumbar catheter placement or puncture by air (3-5 ml) to highlight the suprasellar region and basal cisterns.The main stages of microscopic endonasal transsphenoidal intervention were as follows:1) After the nasal mucosa was treated with an antiseptic solution, a nasal speculum was installed.2) Subsequently, the mucous membrane and the posterior segment of the nasal septum underwent dissected.3) The mucous membrane was separated from the anterior wall of the sphenoid sinus.4) Using bone cutters or a high-speed burr, two holes were sequentially made in the anterior wall of the sphenoid sinus and on the bottom of the sella turcica.5) The dura mater was dissected, and the tumor was removed in a strictly defined sequence: first, the endosellar and infrasellar parts were cut out, and then the suprasellar and laterosellar parts were removed. The instrument manipulations in the area with limited visual control were controlled through a microscope using the EOP. Thus, it was possible to assess the prevalence of the suprasellar region tumors and their removal radicality (the site of the removed tumor becomes lighter on the transducer screen).6) After the tumor removal, the opened bottom of the sella turcica was closed (suturing of the dura mater, placement of the nasal septum fragments between the bottom of the saddle and the dura mater, sealing with a Tachocomb plate, etc.).7) Finally, the tamponade of the nasal cavity was carried out with air ducts placed in the nasal passages and a sling bandage applied to the nose.Group 2 received endoscopic endonasal transsphenoidal surgery by rigid 4 mm endoscopes (Karl Storz, Germany) with four viewing angles (0°, 30°, 45° and 70°). A patient was lying on the back with their head raised 15-30°. Immediately before the operation, tampons moistened with vasoconstrictor drugs were placed inside the patient’s nasal cavity.The main stages of endoscopic endonasal transsphenoidal intervention were as follows:1) After the general examination of the nasal cavity and the use of the antiseptic solution, the nasal passage was selected for the nasal septum curvature.2) Increasing the additional lumen of the operating channel required the middle turbinate lateralization. A nasal dilator was placed in cases of a deviated nasal septum or a narrow lumen of the nasal passages.3) After discovering the natural fistula of the main sinus, partial removal of the nasal mucosa from the anterior wall of the sphenoid sinus was carried out via coagulation and using a debrider.4) After removing the mucosa, a hole was made in the anterior wall of the main sinus by expanding its mouth with the lateral displacement the nasal septum posterior parts.5) The sphenoid sinus mucous membrane coagulated in the area of trepanation.6) After making a hole in the sella turcica bottom, the dura mater was dissected and the tumor tissue was removed.7) Upon tumor resection, the floor of the sella turcica was securely sealed.Compared to the microscopic intervention, the endoscopic procedure did not require the tamponade of the nasal cavity. Therefore, the final step was the repositioning of nasal turbinates. In case of bleeding, a hemostatic nasal sponge can be inserted into the middle nasal passage.In all cases where pituitary adenoma was removed to prevent postoperative liquorrhea (even in the absence thereof), the sella turcica was sealed using TachoComb Baxter plates in combination with fibrin-thrombin glue (Evisel ETICON). In case of large defects at the saddle bottom, a temporary balloon catheter was placed into the main sinus cavity.