Transsphenoidal microsurgery for craniopharyngioma

Cranial base strategies for resection of craniopharyngioma in children

The optimal treatment of craniopharyngioma in children remains a challenge. The use of complete excision to minimize recurrence continues to be controversial because of the risk of postoperative morbidity and death. Advances in skull base approaches, modern microsurgical techniques, neuroimaging, and hormone replacement therapy, however, have allowed safe gross- or near-total resection in the majority of cases. Total removal of these tumors, if possible, offers the best chance of cure for the patient. Although craniopharyngiomas are not strictly tumors of skull base origin, their intimate relationship with the neurovascular structures of this region often requires a skull base approach to maximize the surgical corridor and facilitate adequate microsurgical resection. In this review, the authors focus on commonly used skull base approaches for the surgical management of craniopharyngioma. They discuss the relative indications, advantages, disadvantages, and complications associated with each approach. Illustrative cases and intra-operative videos are presented.

Long-term neurological, visual, and endocrine outcomes following transnasal resection of craniopharyngioma

OBJECT

The authors report on a cohort of patients with craniopharyngioma treated principally through transnasal (TN) resection and followed up for a minimum of 5 years. More specifically, they evaluate the role of the TN approach in the management of craniopharyngioma.

METHODS

Between 1984 and 1994, 68 patients underwent TN resection of craniopharyngiomas at the University of Southern California. The tumor was at least partially cystic in 88% of cases. Four tumors were purely intrasellar, 53 had intra- and suprasellar components, and 11 were exclusively suprasellar. During the same period, 18 patients underwent transcranial (TC) resection of purely suprasellar craniopharyngiomas. Long-term neurological, visual, and endocrine outcomes were reviewed for all patients. In 61 (90%) of 68 patients in the TN group, total resection was achieved, according to 3-month postoperative magnetic resonance images, although four patients suffered a recurrence. Three (43%) of the seven tumors that had been partially resected were enlarged on serial imaging. Fifty-four (87%) of 62 patients with preoperative visual loss experienced improvement in one or both eyes, but two patients (3%) with exclusively suprasellar tumors experienced postoperative visual worsening in one or both eyes. New instances of postoperative endocrinopathy (that is, not present preoperatively) occurred as follows: hypogonadism (eight of 22 cases), growth hormone (GH) deficiency (four of 18 cases), hypothyroidism (11 of 49 cases), hypocortisolemia (nine of 52 cases), and diabetes insipidus (DI; four of 61 cases). One case each of hypocortisolemia and hypothyroidism resolved after surgery. Hyperphagia occurred in 27 (40%) of 68 patients. One patient had short-term memory loss. Postoperative complications included one case of cerebrospinal fluid leak. Among the 18 patients in the TC group, 11 had complete resections. In one case (9%) the tumors recurred. Three (43%) of the seven subtotally resected tumors grew during the follow-up interval. Vision improved in 11 (61%) of 18 cases and worsened in three (17%) as a result of surgery. New instances of postoperative endocrinopathy occurred as follows: hypogonadism (one of six cases), GH deficiency (four of seven cases), hypothyroidism (11 of 14 cases), hypocortisolemia (eight of 15 cases), and DI (nine of 16 cases). No instance of preoperative endocrinopathy was corrected through TC surgery. Four patients (22%) exhibited short-term memory loss and 11 (61%) had hyperphagia after surgery. When compared with those in the TC group, patients in the TN group had shorter hospital stays.

CONCLUSIONS

Use of the TN approach can render good outcomes in properly selected patients with craniopharyngioma, particularly when the tumor is cystic. Even in mostly suprasellar cases, an extended TN approach can afford complete resection. Note that endocrine function often worsens after surgery and that postoperative obesity can be a significant problem.

The extended direct endonasal transsphenoidal approach for nonadenomatous suprasellar tumors

Object. The extended transsphenoidal approach, which requires a bone and dural opening through the tuberculum sellae and posterior planum sphenoidale, is increasingly used for the treatment of nonadenomatous suprasellar tumors. The authors present their experiences in using the direct endonasal approach in patients with nonadenomatous suprasellar tumors.

Methods. Surgery was performed with the aid of an operating microscope and angled endoscopes were used to assess the completeness of resection. Bone and dural defects were repaired using abdominal fat, collagen sponge, titanium mesh, and, in most cases, lumbar drainage of cerebrospinal fluid (CSF).

Twenty-six procedures for tumor removal were performed in 24 patients (ages 9–79 years), including two repeated operations for residual tumor. Gross-total removal could be accomplished in only 46% of patients, with near-gross-total removal or better in 74% of 23 patients (five of eight with craniopharyngiomas, six of seven with meningiomas, five of six with Rathke cleft cysts, and one of two with a dermoid or epidermoid cyst); a patient with a lymphoma only underwent biopsy. Of 13 patients with tumor-related visual loss, 85% improved postoperatively. The complications that occurred included five patients (21%) with postoperative CSF leaks, one patient (4%) with bacterial meningitis; five patients (21%) with new endocrinopathy; and two patients (8%) who needed to undergo repeated operations to downsize suprasellar fat grafts. The only permanent neurological deficit was anosmia in one patient; there were no intracranial vascular injuries.

Conclusions. The direct endonasal skull-base approach provides an effective minimally invasive means for resecting or debulking nonadenomatous suprasellar tumors that have traditionally been approached through a sublabial or transcranial route. Procedures in the supraglandular space can be performed effectively with excellent visualization of the optic apparatus while preserving pituitary function in most cases. The major challenge remains developing consistently effective techniques to prevent postoperative CSF leaks.

Endocrinological outcome of different treatment options in children with craniopharyngioma: a retrospective analysis of 66 cases

Craniopharyngioma is one of the leading causes of hypothalamic-pituitary dysfunction in childhood, caused either by the tumor itself or the consequences of treatment. Tumor management in terms of recurrence rate, quality of life and complications is still controversial. Sixty-six patients with craniopharyngioma at pediatric age were reviewed for symptoms, signs, types of treatment, recurrence rates, complications, and endocrinological outcome. The majority of symptoms was related to the neurological system. Complaints only affecting the endocrinological system were seen in 6% of patients. The most frequent complaints were headache and vomiting (74.2%). The main endocrinological complaints were polyuria and polydipsia (15%), and lassitude (10.6%). Although short stature was a symptom in 9.1% of patients, it was a finding in 39.7% of patients. Plain skull X-rays raised the suspicion of intracranial tumor in more than 90% of children with craniopharyngioma. Recurrence rates were independent of the extent of tumor removal (total or subtotal). The frequency of endocrine dysfunction increased significantly after treatment. The most frequent hypothalamic-pituitary dysfunction was growth hormone deficiency (100%) and gonadotropin deficiency (80%). Hypothyroidism was diagnosed in 74% of patients. The frequency of hypothalamic-pituitary dysfunction was not affected by the extent of tumor removal. Radiotherapy did not increase the frequency of endocrine dysfunctions further. In conclusion, growth follow-up in childhood seems to be an important indicator of craniopharyngioma in early diagnosis. Radiotherapy and extent of tumor removal - either total or subtotal - did not influence endocrine outcome.

The role of transsphenoidal surgery in the treatment of craniopharyngiomas

Object. The optimal approach for the surgical treatment of craniopharyngiomas is still debated. In all cases involving the sella turcica, the authors have exclusively used transsphenoidal surgery (TSS), assuming that this approach is less traumatic than an intracranial one. Moreover, TSS was also performed in some cases of purely suprasellar craniopharyngiomas. In this study the surgical indications and the results obtained in all patients who had undergone TSS were analyzed.

Methods. In a series of 92 patients who underwent surgery for craniopharyngiomas, TSS was the first choice of approach in 57 cases (62%) consisting of 29 female and 28 male patients with ages ranging from 12 to 79 years (mean 35 years). The follow-up duration ranged from 2 to 20 years. A standard transsphenoidal approach was used in patients with an exclusively intrasellar (11 patients) or an intrasellar and suprasellar tumor (37 patients); in nine cases of tumors located exclusively above the sella turcica, a transsphenoidal presellar approach (seven patients) or a transsellar—transdiaphragmatic approach (two patients) was used. Total removal was performed in 36 patients (63%). All patients had good clinical results. Postoperative cerebrospinal fluid leakage occurred in 10 cases, but only one case required a surgical repair of the sella. Two patients died of late complications (3.5%). There were eight cases (14%) of tumor regrowth.

Conclusions. The authors assert that, when used in appropriately located craniopharyngiomas and by neurosurgeons with extensive experience in pituitary surgery, TSS offers excellent results with minor risks.

Craniopharyngioma in adults and children: a study of 122 surgical cases

OBJECT

This work is devoted to a 25-year retrospective study of 122 cases of craniopharyngiomas in adults and children treated and followed by the same neurosurgeon (R.V.E.). In this homogeneous series, the aim was total microsurgical removal of the tumor, without postoperative radiotherapy.

METHODS

The operation was performed via a frontopterional approach in 112 cases and a transsphenoidal approach in 10 cases. The tumor removal was considered total in 59%, subtotal in 29%, and partial in 12%. The surgical mortality rate was 2.5%. Even when tumor removal was not complete, radiotherapy was not systematically administered; it was reserved for cases of recurrence. The authors have studied clinical signs, operative characteristics, and ophthalmological, endocrinological, and functional outcomes, as well as recurrence risk and long-term patient survival. The mean follow-up period was 7 years. The functional results in these patients were excellent in 85%, good in 9%, fair in 5% (usually because of ophthalmological sequelae), and poor in 1%. Tumors recurred in 29 patients, but the salvage treatment, by operation or radiotherapy, was successful in 83%. The actuarial patient survival rate was 92% after 5 years and 85% after 10 years.

CONCLUSIONS

These results compared favorably with the data reported in the literature, suggesting that radical surgery of craniopharyngiomas allows good outcome in terms of survival, full recovery, and quality of life for both adults and children.

Tumors of the skull base in children: review of tumor types and management strategies

Although many treatment strategies for skull base tumors in adults have been reported, relatively little has been reported regarding such therapies in the pediatric population. Skull base tumors in children present a therapeutic challenge because of their unique pathological composition, the constraints of the maturing skull and brain, and the small size of the patients. In this review, the authors examine the pediatric skull base lesions that occur in the anterior, middle, and posterior cranial base, focusing on unique pediatric tumors such as encepahalocele, fibrous dysplasia, esthesioneuroblastoma, craniopharyngioma, juvenile nasopharyngeal angiofibroma, cholesteatoma, chordoma, chondrosarcoma, and Ewing sarcoma. They review management strategies that include radio- and chemotherapy, as well as surgical approaches with emphasis on the modifications and complications associated with the procedures as they apply in children. Evidence for the advantages and limitations of radiotherapy, chemotherapy, and surgery as it pertains to the pediatric population will be examined. With a working knowledge of skull base anatomy and special considerations of the developing craniofacial skeleton, neurosurgeons can treat skull base lesions in children with acceptable morbidity and mortality rates. Outcomes in this population may be better than those in adults, in part because of the benign histopathology that frequently affects the pediatric skull base, as well as the plasticity of the maturing nervous system.

Transsphenoidal Approaches for the Extracapsular Resection of Midline Suprasellar and Anterior Cranial Base Lesions

OBJECTIVE

The transsphenoidal approach is an effective method for treating tumors contained within the sella or extending into the suprasellar cistern. The technique of tumor dissection is predicated on preservation of the integrity of the diaphragma, i.e., intracapsular removal. Gross total extracapsular dissection may, however, be accomplished either by using a standard approach to the pituitary fossa or by extending the exposure to include removal of a portion of the planum sphenoidale and division of the superior intercavernous sinus.

METHODS

Included in this series were 14 patients with parasellar or sellar tumors with extension into the anterior fossa and/or suprasellar cistern. For 4 of 14 patients (29%), extracapsular access was gained by broaching the tumor capsule from within the pituitary fossa. For the remaining 10 of 14 patients (71%), the dura of the floor of the sella and the planum sphenoidale was exposed, using neuronavigation to verify the limits of bony dissection; extracapsular tumor resection was performed using the operating microscope and endoscopy as indicated. The dural defect was repaired with abdominal fat, the sellar floor and planum sphenoidale were reconstructed, and in selected cases a lumbar drain was placed.

RESULTS

Seven of 14 tumors (50%) were craniopharyngiomas, 3 of 14 (21%) were pituitary adenomas, and 2 of 14 (14%) were meningiomas. There was one case of lymphocytic hypophysitis and one yolk sac tumor. Gross total resection was possible in 11 of 14 cases (79%). Immediate postoperative visual function worsened in 2 of 14 cases (14%), improved in 3 of 14 cases (21%), and was stable in the remainder of cases. Postoperatively, 2 of 14 patients (14%) developed bacterial meningitis. Overt postoperative cerebrospinal fluid rhinorrhea was not observed.

CONCLUSION

Gross total extracapsular resection of midline suprasellar tumors via a transsphenoidal approach is possible but is associated with a higher risk of complications than is standard transsphenoidal surgery.

Does craniopharyngioma metastasize? Case report and review of the literature

OBJECTIVE AND IMPORTANCE

A rare case of recurrent craniopharyngioma at an ectopic location is described. This recurrence suggested cerebrospinal fluid seeding.

CLINICAL PRESENTATION

A 65-year-old man presented for follow-up of persisting visual field defect. He had undergone total resection of a suprasellar craniopharyngioma via a subfrontal approach 3 years before presentation. Recent magnetic resonance imaging scans revealed a contrast-enhancing tumor with cystic and solid components at the right temporal lobe. The primary tumor bed was intact.

INTERVENTION

A temporal craniotomy was performed for total resection of the tumor. Intraoperative findings revealed that the recurrent tumor was anatomically unrelated to the previous surgical track. Histological studies of the tumor specimen demonstrated a benign craniopharyngioma. Cerebrospinal fluid spreading was suspected to be the sole route for the recurrence.

CONCLUSION

The case presented here and a review of reports on remote recurrence of craniopharyngioma suggest that care is required during intraoperative handling of the tumor and that long-term follow-up should be performed even in patients whose primary tumor was resected completely.

Resection of suprasellar tumors by using a modified transsphenoidal approach. Report of four cases

Generally accepted contraindications to using a transsphenoidal approach for resection of tumors that arise in or extend into the suprasellar region include a normal-sized sella turcica, normal pituitary function, and adherence of tumor to vital intracranial structures. Thus, the transsphenoidal approach has traditionally been restricted to the removal of tumors involving the pituitary fossa and, occasionally, to suprasellar extensions of such tumors if the sella is enlarged. However, conventional transcranial approaches to the suprasellar region require significant brain retraction and offer limited visualization of contralateral tumor extension and the interface between the tumor and adjacent structures, such as the hypothalamus, third ventricle, optic apparatus, and major arteries. In this paper the authors describe successful removal of suprasellar tumors by using a modified transsphenoidal approach that circumvents some of the traditional contraindications to transsphenoidal surgery, while avoiding some of the disadvantages of transcranial surgery. Four patients harbored tumors (two craniopharyngiomas and two hemangioblastomas) that arose in the suprasellar region and were located either entirely (three patients) or primarily (one patient) within the suprasellar space. All patients had a normal-sized sella turcica. Preoperatively, three of the four patients had significant endocrinological deficits signifying involvement of the hypothalamus, pituitary stalk, or pituitary gland. Two patients exhibited preoperative visual field defects. For tumor excision, a recently described modification of the traditional transsphenoidal approach was used. Using this modification, one removes the posterior portion of the planum sphenoidale, allowing access to the suprasellar region. Total resection of tumor was achieved (including absence of residual tumor on follow-up imaging) in three of the four patients. In the remaining patient, total removal was not possible because of adherence of tumor to the hypothalamus and midbrain. One postoperative cerebrospinal fluid leak occurred. Postoperative endocrinological function was worse than preoperative function in one patient. No other new postoperative endocrinological or neurological deficits were encountered. This study demonstrates the feasibility of using a modified transsphenoidal approach for resection of certain suprasellar, nonpituitary tumors.

Cystic lesions of the pituitary: clinicopathological features distinguishing craniopharyngioma, Rathke's cleft cyst, and arachnoid cyst

The distinction among craniopharyngioma (CR), Rathke's cleft cyst (RCC), and intrasellar arachnoid cyst (AC) remains a difficult preoperative problem. Accurate diagnosis of these rare pituitary lesions is important to determine the type of treatment and predict prognostic outcome. The majority of the literature describes the clinical manifestations and management of only one of CR, RCC, or AC, rendering comparisons difficult. We conducted a study to 1) investigate distinguishing preoperative clinical, biochemical, and radiographic features of patients with CR, RCC, and AC; and 2) identify clinicopathological features that independently predict recurrence in CR and RCC in adults. Fifty-two adult patients included 21 patients with CR (mean age at initial surgery, 35 +/- 14 yr), 26 patients with RCC (mean age, 37 +/- 14 yr), and 5 patients with AC (mean age, 53 +/- 12 yr). Mean follow-up duration was 70 +/- 13 months. Patients with CR presented with hypopituitarism in 95% of cases and hyperprolactinemia in 38%. These patients also had more preoperative neurological deficits (67%), ophthalmological complaints (67%), and significantly higher psychiatric manifestations (33%; P = 0.003) than those with RCC or AC. Patients with AC presented with headaches (60%), visual field deficits (60%), or impotence (50%) in the absence of other specific endocrine dysfunction symptoms. Using biochemical criteria, the percentage of patients with two or more pituitary hormonal axes impaired preoperatively was 67% for CR and 62% for RCC, significantly greater (P = 0.03) than that for the AC patients who had pituitary dysfunction of only one axis. The composition of CR lesions was cystic (38%), solid (10%), or mixed solid and cystic (43%). Patients with RCC or AC groups had a significantly greater proportion (P = 0.006) of purely cystic lesions (88% and 100%, respectively). Calcification detectable on computed tomographic scanning was present in 87% of patients with CR, a significantly greater proportion (P < 0.001) compared to those with RCC (13%) or AC (0%). No significant differences were found between the groups based on computed tomography density, the presence of postcontrast enhancement, or magnetic resonance imaging. Recurrence rate was 62% for CR, 19% for RCC, and 20% for AC. Surgical intervention statistically improved most neurological, ophthalmological, and psychiatric manifestations; in contrast, galactorrhea, menstrual dysfunction, and diabetes insipidus (52% CR; 31% RCC) did not improve or became worse postoperatively. A significantly higher percentage of patients with CR required postoperative hormone replacement. Similarly, there was a biochemical trend suggesting that a smaller proportion of patients with CR improved in at least one pituitary axis after surgery (P = 0.08) compared to those with RCC or AC. There was a positive correlation between cyst size and recurrence rate (r = 0.689; P < 0.01) and between cyst size and time to recurrence (r = 0.582; P = 0.037) for all three groups. We describe the largest clinical, biochemical, radiographic, and histological series of adult patients with cystic disease of the sella turcica. Patients with AC tended to be older at initial diagnosis than CR or RCC patients. Mass effects, such as visual problems and headaches, are common symptoms of all three cystic lesions, but psychiatric deficits favor a diagnosis of CR. Calcification or solid components on neuroimaging characterize CR. Endocrinological deficits, especially diabetes insipidus, had the worst prognosis after surgery. Low recurrence rates can be expected for RCC and AC. These data have direct implications for the management and monitoring of patients with cystic lesions of the sella turcica.

New developments in pituitary surgical techniques

Despite ongoing advances in the pharmacological, radiotherapeutic and endocrine management of pituitary tumours, surgery remains the therapy of choice for the large majority of these lesions. As surgical efficacy is now being judged by more rigorous technical standards and by more stringent endocrine criteria than ever before, such scrutiny has only served to reinforce the fundamental role of surgery in pituitary tumour management. With the revival of the trans-sphenoidal approach, together with its ongoing technical evolution during the past three decades, pituitary tumours have emerged as eminently treatable lesions, with trans-sphenoidal microsurgery affording long-term, high-quality survival in many patients. Pituitary surgery is, however, not without limitation or liability. Even in experienced hands, endocrine and/or oncological remission is not uniformly achieved. Moreover, of those patients in whom such 'cures' can be induced, the durability of the response is not absolute, as tumour recurrence will continue to threaten a small but significant proportion of patients over time. Finally, and notwithstanding the fact that trans-sphenoidal surgery remains one of the safest procedures in contemporary, neurosurgical practice, complications can occur, some of which can be associated with significant morbidity and, on rare occasions, mortality. Clearly, there continue to be areas in need of improvement, and it has been in response to these limitations of contemporary pituitary surgery that neurosurgeons have sought to develop alternative strategies to improve surgical outcome. As a result, a variety of important innovations have been introduced during recent years. Among others, the most important and effective of these have been the application of neuronavigational techniques, trans-sphenoidal endoscopy and intraoperative MR resection control to the standard trans-sphenoidal approach to pituitary tumours. Whereas some advances are conceptual and others are technical, all are helping to push the limits of pituitary surgery to new frontiers of efficacy and safety. In this chapter, the current state of the art of pituitary surgery is reviewed along with those important new developments that, in the foreseeable future, hope to improve the quality of surgical care available to the pituitary tumour patient.

Diagnosis, treatment, and outcome of pituitary tumors and other abnormal intrasellar masses. Retrospective analysis of 353 patients

We reviewed the clinical features, essential laboratory data, pituitary imaging findings (computerized tomography and magnetic resonance imaging), management, and outcome of 353 consecutive patients with the presumptive diagnosis of pituitary tumor investigated from January 1984 through December 1997 at University Hospital, Lausanne, Switzerland. In 18 cases primary empty sella turcica was diagnosed, and in 13 cases of pseudacromegaly there were no endocrine abnormalities. The remaining 322 patients disclosed abnormal pituitary masses, including 275 pituitary adenomas, 18 craniopharyngiomas, 6 cases of primary pituitary hyperplasia, 6 intrasellar meningiomas, 6 cases of distant metastases, 4 intrasellar cysts, 2 chordomas, 1 primary lymphoma, and 1 astrocytoma. Biologic data and immunohistochemical analysis of the excised tissues demonstrated that prolactinomas and nonsecreting adenomas (NSAs) were the most frequent pituitary tumors (40% and 39%, respectively), followed by somatotropic adenomas with acromegaly (11%) and Cushing disease (6%). In contrast with the vast majority of NSAs, which significantly expressed glycoprotein hormones in tissue without secreting them, there was a small group of glycoprotein hormone-secreting adenomas (2%), which had a more severe clinical course after surgery. Thirty-eight pituitary masses were incidentally discovered, most of them NSAs. The expansion of pituitary adenomas into the right cavernous sinus was twice as frequent as to the left cavernous sinus. For the differential diagnosis of hyperprolactinemia, basal prolactin (PRL) levels above 85 micrograms/L, in the absence of renal failure and PRL-enhancing drugs, and a PRL increment of less than 30% after thyrotropin-releasing hormone (TRH) accurately ruled out functional hyperprolactinemia due to NSA, and were typical of prolactinomas. For screening and follow-up of acromegaly, basal growth hormone (GH) and insulin-like growth factor 1 (IGF-1) levels, as well as the paradoxical GH response to TRH (present in 2/3 acromegalic patients), could be used as convenient tools, but the most accurate test for diagnosis and prediction of outcome after therapy was GH (lack of) suppression during oral glucose tolerance test. In Cushing disease, single evening plasma cortisol was as good as the overnight dexamethasone suppression test for screening, and a combined dexamethasoneovine corticotropin-releasing hormone (oCRH) test was as accurate as the long dexamethasone suppression test to confirm the diagnosis. Bilateral inferior petrosal sinus catheterization coupled with oCRH test confirmed the pituitary origin of excess adrenocorticotropic hormone (ACTH) in all patients, including those with normal pituitary on magnetic resonance imaging (50% of the cases). However, this procedure failed to predict tumor localization correctly within the pituitary in 21% of patients. Pituitary cysts, meningiomas, and craniopharyngiomas with an intrasellar component were correctly diagnosed based on pituitary imaging in 75%, 67%, and 44% of cases, respectively. The remainder, as well as the cases of pituitary hyperplasia, metastases, and other less frequent pathologies, were initially diagnosed as NSAs or as masses of unknown nature. When surgery was indicated, pituitary adenomas and other intrasellar masses were operated on by the transsphenoidal route, with the exception of 100% of meningiomas, 83% of craniopharyngiomas, and 10% of NSAs, which were operated on by the transcranial route. Favorable late surgical outcome of prolactinomas could be predicted by a restored PRL response to TRH. However, dopamine agonist (DA) therapy, usually resulting in satisfactory control of PRL levels and in tumor shrinkage, progressively displaced surgery as primary treatment for prolactinomas throughout the study period. After full-term pregnancy, the size of prolactinoma decreased in 7 of 9 patients, and PRL was normal in 2. Surgery was the first treatment for NSAs, with a tumor rela

Transnasal surgery for infradiaphragmatic craniopharyngiomas in pediatric patients

OBJECTIVE

Transnasal surgery has been performed in only a small number of cases of pediatric craniopharyngiomas, and its efficacy is still a matter of debate.

METHODS

We analyzed the results of transnasal surgery performed in 11 pediatric patients (6 male and 5 female patients) with infradiaphragmatic craniopharyngiomas who were younger than 15 years at the time of surgery (age range, 7.7-14.9 yr) and who were treated between 1985 and 1996, when more refined diagnostic and surgical techniques were available. Two of the patients had undergone primary surgery elsewhere. The transnasal approach was chosen because of sellar enlargement and the presence of an infradiaphragmatic tumor. The duration of the clinical follow-up period was at least 1 year.

RESULTS

Five patients required drilling of incompletely pneumatized sphenoid sinuses to reach the sella, but in no cases were the anatomic differences related to patient age or size thought to be a limiting factor in the transnasal procedure. The normal pituitary gland was incised to expose a dorsally located tumor in each of eight patients (72.7%). This surgical procedure has never provoked any major functional damage to the anterior pituitary gland. Complete tumor resection was achieved in three patients (27.3%) and subtotal removal in eight (72.7%). Twenty-two (95.7%) of 23 normal functions were preserved after subtotal tumor removal. In contrast, only one of four normal functions was maintained after complete tumor resection. Persistent diabetes insipidus occurred after total tumor resection in one patient. Tumor regrowth occurred in two patients. No tumor recurrence was observed during the follow-up period.

CONCLUSION

Based on the present findings, transnasal surgery seems to be indicated for most infradiaphragmatic craniopharyngiomas occurring in pediatric patients. Transnasal surgery is as safe to perform in pediatric patients as it is in adult patients. The concept of subtotal tumor removal with preservation of pituitary function, avoiding damage to hypothalamic structures and excessive cerebrospinal fluid leakage, seems to be justified in pediatric patients.

Surgical treatment of craniopharyngiomas: experience with 168 patients

OBJECT

The goal of this study was to assess the outcome of surgical management in 168 consecutive patients harboring craniopharyngiomas treated between January 1983 and April 1997.

METHODS

In 148 patients undergoing initial (primary) surgery, the pterional approach was most frequently used (39.2%), followed by the transsphenoidal approach (23.6%). For large retrochiasmatic craniopharyngiomas, the bifrontal interhemispheric approach was used increasingly over the pterional approach and led to improved surgical results. Total tumor removal was accomplished in 45.7% of transcranial and 85.7% of transsphenoidal procedures. The main reasons for incomplete removal were attachment to and/or infiltration of the hypothalamus, major calcifications, and attachment to vascular structures. The success rate in total tumor removal was inferior in the cases of tumor recurrence. The operative mortality rate in transcranial surgery was 1.1% in primary cases and 10.5% in cases of tumor recurrence. No patient died in the group that underwent transsphenoidal surgery. The rate of recurrence-free survival after total removal was 86.9% at 5 years and 81.3% at 10 years. In contrast, the 5-year recurrence-free survival rate was only 48.8% after subtotal removal and 41.5% after partial removal. Following primary surgery, the actuarial survival rate was 92.7% at 10 years, with the best results after complete tumor removal. At last follow up, 117 (79%) of 148 patients who underwent primary surgery were independent and without impairment.

CONCLUSIONS

Total tumor removal while avoiding hazardous intraoperative manipulation provides favorable early results and a high rate of long-term control in craniopharyngiomas.

Surgical treatment of craniopharyngiomas: endocrinological results

OBJECT

This study aimed to elucidate the endocrinological outcome of craniopharyngioma surgery. In particular, endocrinological results were analyzed in relation to the surgical approach. The study includes 143 patients who underwent pre- and postoperative endocrinological assessment and who had not previously undergone surgery.

METHODS

Diabetes insipidus was the most common postoperative deficiency in both the transcranial and transsphenoidal groups. The overall percentage of patients with diabetes insipidus increased from 16.1% preoperatively to 59.4% postoperatively. After transcranial surgery, the rate of anterior pituitary deficiency also increased. However, normal preoperative anterior pituitary function was maintained in more than 50% of patients for each endocrine axis. Similar results were attained in the group of patients undergoing complete tumor removal. The best result was achieved for gonadal function: the incidence of hypogonadism increased only slightly from 77.4 to 79.8%. The rate of anterior pituitary failure at presentation was much higher in the transsphenoidal than in the transcranial group. During transsphenoidal surgery, intact anterior pituitary functions were generally preserved. The rate of panhypopituitarism increased only slightly, from 40% before surgery to 42.9% after surgery. Endocrinological results were not inferior in patients with a ventrally displaced pituitary. This variant required midline incision of the gland for exposure of the craniopharyngioma. In the entire series of 143 patients the pituitary stalk was generally preserved. Postoperative panhypopituitarism was encountered in only one of eight patients in whom the pituitary stalk was partially resected because of tumor infiltration. None of the 88 patients who remained recurrence-free demonstrated endocrinological deterioration during follow-up review, compared with the early postoperative assessment 3 months postsurgery. On the other hand, complete recovery of one endocrine axis was observed in nine of these patients during later follow-up evaluations. In five of them, diabetes insipidus had regressed.

CONCLUSIONS

It is worth preserving the pituitary stalk and gland at surgery because of the definite chance that intact anterior pituitary functions can be maintained. Postoperative diabetes insipidus must be accepted as a common sequela following attempts at complete removal of the craniopharyngioma.

Recent results of primary transnasal surgery for infradiaphragmatic craniopharyngioma

Results of primary transnasal surgery were evaluated in 35 patients (18 males and 17 females) with intrasellar and suprasellar craniopharyngiomas treated between 1985 and 1996 when more refined surgical and diagnostic techniques were available. Patients ranged in age from 8 to 72 years (mean 27 years); 14 patients were younger than 18 years of age. The transnasal approach was chosen because of sellar enlargement and presence of infradiaphragmatic tumor. The paramedian portion of the normal pituitary gland was incised vertically to reach a dorsally located tumor in 25 patients. Complete tumor resection was achieved in 15 patients and subtotal removal in 19; in one patient, only aspiration of cyst contents was performed. Tumor regrowth was seen in three patients after subtotal removal; in two, total tumor removal was achieved by a second transnasal surgery, whereas radiotherapy was administered in the other. In a single patient, total tumor removal was achieved by a second transcranial surgery after cyst aspiration. The duration of the clinical follow-up period was at least 1 year. Persistent diabetes insipidus appeared after total tumor resection in five patients. Cerebrospinal fluid leakage occurred in three patients, with two requiring revision. Among 29 patients with preoperatively normal pituitary functions, 20 (69%) were preserved after primary total resection, whereas six (19.4%) of 31 previously disturbed functions were normalized. After subtotal removal including cyst aspiration, 39 (88.6%) of 44 normal functions were preserved, whereas nine (24.3%) of 37 disturbed functions were normalized. The transnasal approach should be the first choice in infradiaphragmatic craniopharyngiomas with sellar enlargement in cases in which the extrasellar portion is mostly cystic and is accessible. The concept of subtotal removal with preservation of pituitary functions, especially when treating craniopharyngioma in children, seems to be justified.

Surgical treatment of craniopharyngiomas. Part I. Experience with 168 patients

The surgical management of 168 consecutive patients harboring craniopharyngiomas treated between January 1983 and April 1997 is described. In 148 patients undergoing initial (primary) surgery, the pterional approach was most frequently used (39.2%) followed by the transsphenoidal approach (23.6%). For large retrochiasmatic craniopharyngiomas, the bifrontal interhemispheric approach was used increasingly over the pterional approach and led to improved surgical results. Total tumor removal was accomplished in 45.7% of transcranial and 85.7% of transsphenoidal procedures. The main reasons for incomplete removal were attachment and/or infiltration of the hypothalamus, major calcifications, and attachment to vascular structures. The success rate in total tumor removal was inferior in the cases of tumor recurrence. The operative mortality rate in transcranial surgery was 1.1% in primary cases and 10.5% in cases of tumor recurrence. No patient died in the group undergoing transsphenoidal surgery. The rate of recurrence-free survival after total removal was 86.9% at 5 years and 81.3% at 10 years. In contrast, the 5-year recurrence-free survival rate was only 48.8% after subtotal removal and 41.5% after partial removal. Following primary surgery, the actuarial survival rate was 92.7% at 10 years, with the best results after complete tumor removal. At last follow up, 117 (79%) of 148 patients who underwent primary surgery were independent and without impairment.

Total tumor removal while avoiding hazardous intraoperative manipulation provides favorable early results and a high rate of long-term control in craniopharyngiomas.

[Surgical anatomy of the nasal transphenoidal approach for pituitary tumors]

Different distances related to the nasal transphenoidal approach were measured on the hemiheads of eighteen cadavers in order to study its limits and advantages. The main mean measures obtained (mm) were: major diameter of the nostril 15.18: height of the nasal cavity 44.11, nostril-sella turcica distance 71.71. These results show that the nasal approach is wide and direct to the sella turcica. The present study demonstrate the possibility of preservation of the cartilaginous septum and other structures which are usually damaged when the sublabial approach is employed.

Hypothalamic-pituitary dysfunction in patients with craniopharyngioma

OBJECTIVE

Previous studies of preoperative pituitary function in patients with craniopharyngioma have been limited in scope and have focused on children. We have evaluated the impact of craniopharyngiomas and their surgical treatment on pituitary function in a large group of mostly adult patients.

DESIGN

We performed a retrospective study of patients treated at our centre between 1980 and 1992.

PATIENTS

Twenty-two men and 13 women, most of them adults, treated surgically for craniopharyngioma during the above period.

MEASUREMENTS

Serum glucose, GH, LH, FSH, TSH and cortisol were measured both before and after a combined insulin induced hypoglycaemia, GnRH and TRH test. Basal concentrations of thyroid hormones, PRL and gonadal steroids were also measured. Preoperative computed tomographic scan was performed in all patients, and a detailed study of visual function before and after surgery was available for 32 of them. Endocrine function was reevaluated post-operatively.

RESULTS

In preoperative studies, 29 patients had some anterior pituitary deficit and 13 had diabetes insipidus. The most common abnormality was gonadotrophin deficiency, followed by GH deficiency. Dynamic studies suggested a hypothalamic origin for these deficits. In post-surgical evaluation, impaired pituitary function was observed in most patients. Panhypopituitarism was present in 28 cases and diabetes insipidus in 24.

CONCLUSIONS

Our report illustrates the high incidence of endocrine deficits in patients with craniopharyngioma. Additional hypothalamic-pituitary dysfunction usually occurs following surgical treatment of these tumours.

Surgical treatment of craniopharyngiomas: an evaluation of the transsphenoidal and pterional approaches

Fifty-seven patients with craniopharyngiomas underwent a total of 64 operations. Their clinical follow-up ranged from 2.5 to 15.5 years, with a mean follow-up of 6.5 years. A transsphenoidal approach was used in 35 patients (61%), whereas 22 (39%) were operated on using a pterional approach (in 16 patients, the tumor was found in the suprasellar cisterns, and in 6, the tumor was found in the third ventricle and was removed passing through the lamina terminalis). Total removal of the tumor was achieved in 43 patients (75%). In six patients (11%), fragments of the capsule remained attached to the hypothalamus (subtotal removal), and, in eight patients (14%), the tumor was partially removed. No recurrence occurred in those patients in whom removal was total. Regrowth was observed in two patients (33%) in whom removal was subtotal and in two (25%) in whom removal was partial. Three of them underwent subsequent operations, and a total removal with good clinical outcome was achieved. All patients except two had good postoperative recovery. Twenty patients (35%) required hormonal replacement therapy. When transsphenoidal surgery was used, a total removal of the tumors was achieved in 23 (66%) of the patients. Good clinical outcome was seen in all 35 patients. Six patients (17%) required hormonal replacement therapy. When the pterional approach was used for tumors in the suprasellar cisterns, we achieved total removal of tumors in 15 patients (94%). Good clinical outcome was seen in 20 patients (91%). Eleven patients (50%) required hormonal replacement therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

The anterior pituitary lobe in patients with cystic craniopharyngiomas: three cases of associated lymphocytic hypophysitis

Specimens of the anterior pituitary lobe were investigated histologically in 28 craniopharyngioma patients operated on trans-sphenoidally. The pituitary glands in 3 patients revealed lymphocytic invasion giving a histological appearance typical of lymphocytic hypophysitis (incidence: 11%). At follow-up examination all three patients with associated lymphocytic hypophysitis had complete pituitary insufficiency, whereas only 36% of the craniopharyngioma patients without associated lymphocytic hypophysitis were in this poor postoperative endocrine state. The phenomenon of associated lymphocytic hypophysitis in craniopharyngioma patients has not been reported so far. This might be due to the fact that investigators have failed to systematically examine the anterior pituitary lobe in craniopharyngioma patients. The 60 cases of lymphocytic hypophysitis reported in the literature occurred, for the most part, in women during late pregnancy or shortly after delivery. An auto-immune origin is assumed in this type of inflammation. In contrast to this pathophysiological mechanism, we assume a local induction of inflammation resulting from the craniopharyngioma cyst in our 3 patients.

Review of skull base surgery approaches: with special reference to pediatric patients

The techniques of skull base surgery attempt to maximize the exposure of a cranial base lesion while using the least amount of brain retraction. Cranial base surgery is not a 'new' area of neurosurgical or otolaryngologic interest, but instead represents a resurgence of efforts to treat difficult lesions involving the cranial base. This resurgence of interest and effort is a product of recent advances in microanatomical knowledge of the cranial base, advances in microsurgical technique, improved neurophysiologic monitoring, and improved collaborative relationships between neurosurgery, otolaryngology and plastic surgery. Furthermore, improved neuroanesthetic techniques allow the surgeon to proceed with surgery without undue concern about time, and improved neuroimaging techniques provide the surgeon with detailed knowledge of the three dimensional characteristics of the tumor and surrounding structures. This review will focus on the surgical management of cranial base tumors primarily affecting the pediatric population. Little has been written on the techniques of skull base surgery as they apply to the pediatric population, since cranially-based tumors are a relatively rare occurrence in this patient population. In most instances, however, many of the 'standard' skull base approaches can be applied to the pediatric patient with few modifications, and in our experience, the pediatric patients have tolerated these approaches as well as their adult counterparts.