Transsphenoidal surgery using a high definition video telescope for pituitary adenomas in dogs with pituitary dependent hypercortisolism: methods and results.

OBJECTIVE: To (1) establish a technique for transsphenoidal removal of pituitary adenomas in dogs with pituitary dependent hypercortisolism (PDH) using a high definition video telescope, and (2) report initial outcomes. STUDY DESIGN: Prospective case series. ANIMALS: Dogs with pituitary dependent hypercortisolism (PDH; n = 26) with suprasellar masses. METHODS: Pituitary tumors were removed using a modification of a transoral transsphenoidal approach. Surgery was observed using a high definition video telescope (VITOM™) and localization of the sella was performed by drilling pilot holes in the basisphenoid bone followed by computed tomography (CT). RESULTS: Dogs had PDH confirmed by urinary cortisol to creatinine ratio (UCCR) and endogenous ACTH assays, and tumors confirmed by MRI. There were no postoperative cerebrospinal fluid leaks, wound dehiscence, or surgical site infections. Overall postoperative mortality was 19% with no mortality observed in the last 16 dogs, indicating an initial "learning curve" followed by good surgical results. All dogs that survived the immediate postoperative period (1 week) returned to their owners in good health, on hormonal replacement therapy. Follow-up ranged from 3 to 36 months. Sustained tumor control and hormonal remission based on normalized ACTH and UCCR measurements were observed in 20/21 (95%) dogs at 1-year follow-up. CONCLUSIONS: Modifications of a trans-oral transsphenoidal technique for surgical removal of pituitary tumors provides a safe and effective strategy for long-term remission of PDH with acceptable morbidity and mortality.

[Clinical application of a new titanium clip applier in transsphenoidal surgery].

OBJECTIVE: To explore the efficacy and safety of a new titanium clip applier in transsphenoidal surgery for the A specially devised surgery instrument was developed and effectively applied in the management of intercavernous sinus hemorrhage and cerebrospinal fluid (CSF) leakage in transsphenoidal surgery. METHODS: A total of 34 consecutive patients with pituiary adenoma underwent transsphenoidal surgery via a new deep pistol-shaped clip applier versus titanium clip. It was 21 cm long with a rectangular forepart. All patients were evaluated clinically and radiologically at 24 months and magnetic resonance imaging (MRI) was performed at Months 3-18 postoperation. RESULTS: The application of such a new clip applier was effective. No operation was terminated due to ineffective hemorrhage, postoperative CSF leakage or related complications. Postoperative imaging studies revealed no significant evidence of clip artifact. CONCLUSION: The technique of hemostasis and leakage clogging with such a new clip applier is safer, faster and more reliable than its conventional counterpart in achieving dural closure and intercavernous sinus hemostasis.

[Technical peculiarities of trans-sphenoidal surgical interventions for prolactin-secreting pituitary adenoma].

The results of treatment of 84 patients, operated on for prolactinoma, using transsphenoidal access, were analyzed. All the stages of transsphenoidal surgical treatment are depicted in details, beginning from the patient's position on operative table and distribution of the devices in operating room and up to performance of nasal tamponade. There was established the dependence of the surgical intervention radicalism from the tumor topographo-histological peculiarities and from the earlier conducted treatment as well.

Results of endoscopic transsphenoidal pituitary surgery in 40 patients with a growth hormone-secreting macroadenoma.

OBJECTIVE: Transsphenoidal pituitary surgery (TS) is the primary treatment of choice for patients with acromegaly. Macroadenomas (>1 cm) are more difficult to resect than microadenomas (remission rate ± 50% compared to ± 90%). Besides the conventional microscopic TS, the more recently introduced endoscopic technique is nowadays frequently used. However, no large series reporting on its results have yet been published. We evaluated the outcome of endoscopic TS in 40 patients with a growth hormone (GH)-secreting macroadenoma treated in our hospital between 1998 and 2007. METHODS: Medical records were retrospectively reviewed. Remission was defined as disappearance of clinical symptoms of acromegaly, normal serum insulin-like growth factor-1 levels (≤2 SD) and serum GH levels suppressed to <2 mU/l after an oral glucose tolerance test within the first 4 months after TS. RESULTS: In four patients TS aimed at debulking of the tumour. In the remaining 36 patients, remission was achieved in 20 patients. In the first 5 years remission was achieved in 6 out of 18 patients (33%) compared to 14 out of 22 patients (63%) in the following 5 years (p = 0.06). Thirteen patients had a mild perioperative complication. Before TS 15 patients received hormonal substitution therapy compared to 12 patients (33%) after TS. CONCLUSION: Endoscopic TS is a good primary therapeutic option for patients with a GH-secreting macroadenoma, resulting in a remission rate of up to 63% in experienced hands. This technique can potentially improve the outcome of TS in these patients.

Combined simultaneous transcranial and transsphenoidal resection of large-to-giant pituitary adenomas.

BACKGROUND: While large-to-giant pituitary adenomas (PAs) may be safely removed by experienced surgeons through a single route, the procedure is technically challenging. We present the outcome of a simultaneous combined transcranial and transsphenoidal approach and discuss its applications. METHODS: A retrospective review was conducted on 12 consecutive patients. Surgical complications, visual and endocrinological functions, and tumour control were reviewed. RESULTS: There were four men and eight women, with a mean age of 47.6 years. All but one patient had non-functioning PAs. The mean tumour height was 4.1 cm (range: 2.3-5.5). The predominant presenting symptoms were visual field loss in eight patients, headache in three patients and mental confusion in one patient. There was no operative mortality. Post-operative cerebrospinal fluid leakage occurred in one patient. Five of the eight patients who presented with visual field loss achieved full recovery, and three had partial improvement. Two patients developed permanent diabetes insipidus after surgery. Panhypopituitarism occurred in one patient. Gross total removal (GTR) was achieved in five, and subtotal removal (STR) in seven patients. Seven patients received post-operative external irradiation. All patients who had GTR remained tumour-free and all those with STR had stable diseases after a mean follow-up period of 53.1 months (range: 14.1-92.1). CONCLUSION: The simultaneous 'above and below' approach is a safe and effective surgical strategy for large-to-giant PAs, particularly when expertise in endoscopic transsphenoidal surgery is unavailable. Its use, however, should be limited to a carefully selected group of patients, and tailored to individual user's expertise and experience.

Functional impairments caused by chiasma syndromes prior to and following transsphenoidal pituitary adenoma surgery.

PURPOSE: To describe the functional impairment caused by chiasma syndromes (CS) prior to and following transsphenoidal pituitary adenoma surgery. METHODS: Pertinent data of a successive series of patients operated transsphenoidally for the first time for pituitary adenoma were retrospectively analyzed. The degree of functional impairment caused by the impairment of vision was quantified according to the resulting degree of disability (DOD). A DOD of > or =30 is considered substantial. RESULTS: None of the 197 of 304 (64.9%) patients without preoperative chiasma syndrome (CS) experienced postoperative worsening of their visual acuity or their visual fields. Thus, no change of their vision-related DOD (V-DOD) did occur. One hundred and seven (35.1%) of the patients presented preoperatively with CS. Postoperatively, 42.9% of the CS remitted completely, 38.3% improved, 11.2% remained unchanged, and 7.4% worsened. Accordingly, the median V-DOD improved significantly from 30 (0; 100) to 0 (0; 100). The prevalence of patients with V-DOD > or =30 dropped significantly from 51.4% preoperatively to 16.4% postoperatively. Postoperatively, the median V-DOD improved significantly up to 3 months postoperatively. Thereafter, no further significant changes occurred. However, in patients with preoperative CS, the median V-DOD as well as the prevalence of patients with a V-DOD > or =30 remained postoperatively significantly higher compared to patients without preoperative CS. CONCLUSIONS: Visual impairments due to CS frequently caused substantial DOD preoperatively. Postoperatively, the median degree of V-DOD as well as the prevalence of substantial V-DOD improved significantly. However, in patients with preoperative CS, V-DOD remained postoperatively significantly higher than V-DOD of patients without preoperative CS.

[Methods of the endoscopic endonasal transsphenoidal adenomectomy].

This paper provides the practical part of a procedure for endoscopic endonasal transsphenoidal resection of pituitary tumors. The authors have presently gained experience with about 400 endoscopic endonasal transsphenoidal operations. The advantages of endoscopic surgery include the wide vision field of an operative site under good illumination. The endoscopic intervention provides a possibility of extracting not only endo-, but also paracellular portions of a tumor under direct visual control, which can be rarely done during a standard microscopic transnasal operation. The paper gives recommendations on the equipment of an operating suite and anesthetic maintenance. It also describes surgical stages and postoperative management of patients.

[Development of new surgical tools, Q-PAL and HP-Jet for endoscopy only used unilateral transnasal approach for pituitary adenomas].

UNLABELLED: The aim of this study is to present surgical techniques and results of endoscope-assisted transnasal approach (TNA) for pituitary adenomas. It is a new alternative for Hardy's surgery (TSS). We performed TNA assisted by only endoscope through single nostril. METHOD: We enter the sphenoid sinus directly through the natural ostium and ablate neither the nasal septum nor the vomer bone. We found the hardest problem of this method resides in its deep and narrow working space which obstructs usage of two tools at same time. To overcome this problem we developed two surgical tools, Q-PAL and HP-Jet. Q-PAL is combination of PAL and suction. We place flexible PAL wire electrode through suction tube so as PAL tip protrudes from suction tip. This eliminates coagulation smoke which otherwise disturbs surgeons view. HP-Jet is a combination of a suction tool and an irrigator. The irrigator is connected to syringe containing saline. Saline is injected manually from tip bursting up tumor tissue with its jet pressure. It is safe and effective instrument suitable for extirpation of rather fragile tissue like adenomas existing in deep and blind spaces. CASES: Since 2004 we have operated on 16 patients using endoscopic TNA. Eight were non-functioning adenomas, and 8 functioning. RESULTS: Results of surgery were compared with those of 10 cases operated by TSS. More than 70% removal of adenoma was achieved in 75% of cases with TNA, but in only 71% with TSS. Postoperative CSF rhinorrhea was seen in one case. Four cases showed postsurgical transient diabetes insipidus. We had no case with postsurgical infection. With the help of instruments having multiple functions in single probe such as Q-PAL and HP-Jet, we can execute endoscopic TNA more smoothly and more safely.

Laser modification to an x-ray collimator: an aid in positioning patients for neurosurgical and radiographic procedures.

In high-ambient-light levels such as are found in operating rooms, and at long target-to-patient distances, the cross lines and light field projected from conventional x-ray collimators are not easily visible and proper patient positioning is difficult. The collimators on two mutually perpendicular x-ray units have been modified by replacing the incandescent bulbs with lasers and adjusting the lasers to be coaxial with the x-ray beams. These modifications have been coupled with a third wall-mounted laser to facilitate patient positioning for stereotaxic thermal hypophysectomy. The use of the laser-modified collimators has resulted in considerable saving of time for the operating team and has markedly reduced patient anesthesia time. The laser-modified collimator has also been found useful in positioning patients for other radiographic procedures in the operating room and has virtually eliminated retakes due to malpositioning.

Endoscopic transseptal transsphenoidal surgery for pituitary tumors.

OBJECTIVE: Transseptal transsphenoidal surgery of pituitary tumors is a well-established surgical technique. The sublabial approach and the open rhinoplasty approach are most commonly used. In both cases, the surgical avenue is along the entire length of the nasal septum, removing both nasal cartilage and the vomer. Septal perforations and upper dental anesthesia are frequent complications of the standard approaches. We describe our initial experience in using the nasal endoscope for the first stage of the operation. METHODS: A nasal endoscope was used to open the anterior wall of the sphenoid sinus. Our initial incision was in the posterior third of the septum, removing only the vomer. After the sphenoid sinus was opened, we inserted a speculum and proceeded with the operation with an operating microscope. After the speculum was in place, it was easier to proceed with the microscope, which allows binocular vision and bimanual operation. RESULTS: The procedure was used for our most recent 14 consecutive patients with pituitary adenomas. No complications related to the approach were encountered for any of the patients in follow-up monitoring. CONCLUSION: The endoscopic transseptal approach to the sphenoid sinus for pituitary surgery was found to be easy, time-saving, and without septal or sublabial complications.

Transnasal endoscopic surgery of the pituitary gland: technical note.

OBJECTIVE: An approach to transnasal transsphenoidal debulking of pituitary tumors using endoscopic guidance is presented. METHODS: Technical details of this approach using an endoscope inserted through one nostril and operating instruments inserted through a submucosal tunnel created via the other nostril are discussed. RESULTS: Ten patients who had operations are tabulated. Illustrative cases are presented. CONCLUSION: Endoscopic debulking of pituitary tumors can provide good results with minimal operative morbidity.

Transnasal microsurgery in children and adolescents with Cushing's disease.

OBJECTIVE: Transnasal adenomectomy is the treatment of choice for Cushing's disease. We review the diagnostic peculiarities, specific surgical problems, and outcome of children and adolescents with Cushing's disease. METHODS: We report on our series of 55 consecutive children and adolescents (range, 4.2-18.9 yr [mean age, 14.4 yr]; female:male = 1.1:1.0; mean follow-up, 54.5 +/- 38.6 mo [standard deviation]) with Cushing's disease on whom we performed surgery since 1980. The indication for transsphenoidal surgery is based on endocrinological parameters and not on neuroradiological findings. RESULTS: Detection rate of the tumor site was 22% using computed tomography and 33% using magnetic resonance imaging. Only 7 of 13 interpetrosal adrenocorticotropic hormone gradients obtained during inferior petrosal sinus sampling correctly lateralized the tumor site preoperatively (53.8%). In cases of incomplete sphenoid pneumatization, adequate exposure is achieved by drilling. The tumor finding rate is 98%. The remission rate is 100% when two early subsequent operations are included. The recurrence rate for 45 primary operations with follow-up of at least 1 year is 15.5%. Seven of nine subsequent operations for recurrent hypercortisolism were successful. One patient needed three more operations until hypercortisolism subsided; one patient achieved remission after additional pituitary irradiation. The surgical morbidity was low in this series, which consisted of two cerebrospinal fluid fistulas. The incidence of hypopituitarism after primary operations (10.3%) is significantly lower than after subsequent operations (45.5%). CONCLUSION: Direct transnasal submucosal surgery for Cushing's disease is successful, and pituitary function can be preserved in most of these young patients.

Modification of the Cushing speculum used for transsphenoidal pituitary surgery. Technical note.

A modification of the original Cushing speculum used in the sublabial-transseptal-transsphenoidal approach to the pituitary is described. Although the modified speculum has smaller dimensions, it allows better visualization of the surgical field, while a new expanding device permits easier opening of the speculum.

A new technique for closure of the dura following transsphenoidal and transclival operations. Technical note.

Watertight closure of the dura following transsphenoidal operations for pituitary adenoma or hypophysectomy and following transclival operations for paraclival tumors has been technically very difficult. This is true both immediately after the initial approach and later for the treatment of delayed cerebrospinal fluid leakage. An innovative practical technique and special suture-tying instruments and needle designed by the principal author for this purpose have greatly facilitated this procedure. This technique has been applied to both direct dural closure and dural patching with watertight dural closure. The technique is also widely applicable for closing (or suturing) the dura following any procedure through a small opening, such as the dural tears occasionally encountered during lumbar or cervical discectomy, or tacking the tentorium during a craniotomy. The technique and suture-tying instruments are described in detail.

Intraoperative magnetic resonance imaging during transsphenoidal surgery.

OBJECT: The aim of this study was to evaluate whether intraoperative magnetic resonance (MR) imaging can increase the efficacy of transsphenoidal microsurgery, primarily in non-hormone-secreting intra- and suprasellar pituitary macroadenomas. METHODS: Intraoperative imaging was performed using a 0.2-tesla MR imager, which was located in a specially designed operating room. The patient was placed supine on the sliding table of the MR imager, with the head placed near the 5-gauss line. A standard flexible coil was placed around the patient's forehead. Microsurgery was performed using MR-compatible instruments. Image acquisition was started after the sliding table had been moved into the center of the magnet. Coronal and sagittal T1-weighted images each required over 8 minutes to acquire, and T2-weighted images were obtained optionally. To assess the reliability of intraoperative evaluation of tumor resection, the intraoperative findings were compared with those on conventional postoperative 1.5-tesla MR images, which were obtained 2 to 3 months after surgery. Among 44 patients with large intra- and suprasellar pituitary adenomas that were mainly hormonally inactive, intraoperative MR imaging allowed an ultra-early evaluation of tumor resection in 73% of cases; such an evaluation is normally only possible 2 to 3 months after surgery. A second intraoperative examination of 24 patients for suspected tumor remnants led to additional resection in 15 patients (34%). CONCLUSIONS: Intraoperative MR imaging undoubtedly offers the option of a second look within the same surgical procedure, if incomplete tumor resection is suspected. Thus, the rate of procedures during which complete tumor removal is achieved can be improved. Furthermore, additional treatments for those patients in whom tumor removal was incomplete can be planned at an early stage, namely just after surgery.

Transnasal transsphenoidal approach to the sella.

The transnasal transsphenoidal approach to the sella turcica has been refined and perfected through advances in medicine and technology. Originally performed for excision of pituitary adenomas, its present primary use is pituitary ablation is hormonally dependent diseases. Our study of 55 patients who have undergone this procedure during the years 1970-1975 demonstrates that this microscopic technique gives excellent exposure and visualization of intrasellar contents. Our method gives excellent exposure and visualization of intrasellar contents. Our method with several instrument modifications is discussed. It is technically an easy procedure with a minimum of morbidigy and mortality.

Charged-particle radiosurgery of the brain.

Charged-particle beams (e.g., protons and helium, carbon and neon ions) manifest unique physical properties which offer advantages for neurosurgery and neuroscience research. The beams have Bragg ionization peaks at depth in tissues, and finite range and are readily collimated to any desired cross-sectional size and shape by metal apertures. Since 1954 nearly 6000 neurosurgical patients worldwide have been treated with stereotactic charged-particle radiosurgery of the brain for various localized and systemic malignant and nonmalignant disorders. Experimental studies with charged-particle beams have been carried out in laboratory animals to characterize anatomic and physiologic correlates of various behavioral and functional properties in the brain. Highly focused charged-particle beams have been used to induce sharply delineated laminar lesions or discrete focal ablation of deep-seated brain structures for the study of the functional anatomy of selected intracranial sites. Charged-particle beam irradiation for stereotactic radiosurgery and radiation oncology of intracranial disorders has achieved increasing importance internationally. More than 30 biomedical accelerator facilities on four continents are currently fully operational, under construction, or in an active planning stage; this last group consists primarily of dedicated biomedical hospital-based facilities. Therapeutic efficacy has been demonstrated clearly for the treatment of selected intracranial sites, e.g., pituitary adenomas and intracranial arteriovenous malformations. Heavier charged particles (e.g., carbon and neon ions) have been found to manifest a number of valuable radiobiologic properties and appear to be of potential advantage in the radiosurgical treatment of those primary or metastatic brain tumors that are radioresistant. The optimal dose and choice of charged-particle species must be determined for the treatment of the different intracranial disorders to improve the cure rate and to minimize potential adverse sequelae of the reaction of the brain to radiation injury.

Transcolumellar approach in transsphenoidal pituitary surgery for patients with small nostril.

OBJECTIVE: Sublabial approach has been widely used as the standard technique for transsphenoidal pituitary surgery. But it has several possible drawbacks, such as; postoperative flat nose deformity, hypesthesia of upper gum, and feeding difficulty until 2 to 3 weeks after surgery. As an alternative, an endonasal approach was adopted for patients who had large nostrils, such as white or acromegalic patients. In patients with small nostrils, especially oriental people, it requires an additional tension release incision that leaves a definitely visible scar at the base of nose. STUDY DESIGN: We applied the transcolumellar approach, which modified the external rhinoplasty approach on the 136 cases of transsphenoidal pituitary surgery that were performed from 1994 to June 1999. RESULTS: In all patients, we found we could reach the anterior portion of nasal septum in 7 to 8 mm in depth from the skin surface and eliminate the disadvantages of sublabial and endonasal approach. Also, this method can markedly reduce the surgical dissection time and blood loss. CONCLUSIONS: We concluded that this technique was relatively simple and more than adequate in most transsphenoidal pituitary surgery, even in patients with small nostrils.

Simplified hypophysectomy technique for young birds.

The present work introduces a modified oral approach to the pituitary gland of the immature bird with improved localization and visualization of the organ in situ. The hypophysectomy procedure is based on simplified instrumentation readily available or constructed with materials present in most, if not all, laboratories. The technique has the added advantage of minimal exsanguination, virtually no operative trauma, and allows for a rapid post operative animal recovery.

Modified rotatory instruments for transphenoidal surgery: technical note.

A series of modified gyratory bayonets instruments is described. They have the advantage to allow any adjustable position within a 360 degree rotation angle, during the various surgical steps of transphenoidal surgery, thus keeping the surgeon's hand always at the same position.