Hardy Grade Research Articles

Outcomes after a purely endoscopic transsphenoidal resection of growth hormone–secreting pituitary adenomas

Using strict biochemical remission criteria, the authors assessed surgical outcomes after endoscopic transsphenoidal resection of growth hormone (GH)-secreting pituitary adenomas and identified preoperative factors that significantly influence the rate of remission. A retrospective review of a prospectively maintained database was performed. The authors reviewed cases in which an endoscopic resection of GH-secreting pituitary adenomas was performed. The cohort consisted of 26 patients who had been followed for 3-60 months (mean 24.5 months). The thresholds of an age-appropriate, normalized insulin-like growth factor-I concentration, a nadir GH level after oral glucose load of less than 1.0 μg/l, and a random GH value of less than 2.5 μg/l were required to establish biochemical cure postoperatively. Overall, in 57.7% of patients undergoing a purely endoscopic transsphenoidal pituitary adenectomy for acromegaly, an endocrinological cure was achieved. The mean clinical follow-up duration was 24.5 months. In patients with microadenomas (4 cases) the cure rate was 75%, whereas in patients harboring macroadenomas (22 cases) the cure rate was 54.5%. Cavernous sinus invasion (Knosp Grades 3 and 4) was associated with a significantly lower remission rate (p = 0.0068). Hardy Grade 3 and 4 tumors were also less likely to achieve biochemical cure (p = 0.013). The overall complication rate was 11.5% including 2 incidents of transient diabetes insipidus and 1 postoperative CSF leak, which were treated nonoperatively. A purely endoscopic transsphenoidal approach to GH-secreting pituitary adenomas leads to similar outcome for noninvasive macroadenomas compared with traditional microsurgical techniques. Furthermore, this approach may often provide maximal visualization of the tumor, the pituitary gland, and the surrounding neurovascular structures.

TRANSSPHENOIDAL PITUITARY MACROADENOMAS RESECTION GUIDED BY POLESTAR N20 LOW-FIELD INTRAOPERATIVE MAGNETIC RESONANCE IMAGING

To evaluate the applicability of low-field intraoperative magnetic resonance imaging (iMRI) during transsphenoidal surgery of pituitary macroadenomas. Fifty-five transsphenoidal surgeries were performed for macroadenomas (modified Hardy's Grade II-IV) resections. All of the surgical processes were guided by real-time updated contrast T1-weighted coronal and sagittal images, which were acquired with 0.15 Tesla PoleStar N20 iMRI (Medtronic Navigation, Louisville, CO). The definitive benefits as well as major drawbacks of low-field iMRI in transsphenoidal surgery were assessed with respect to intraoperative imaging, tumor resection control, comparison with early postoperative high-field magnetic resonance imaging, and follow-up outcomes. Intraoperative imaging revealed residual tumor and guided extended tumor resection in 17 of 55 cases. As a result, the percentage of gross total removal of macroadenomas increased from 58.2% to 83.6%. The accuracy of imaging evaluation of low-field iMRI was 81.8%, compared with early postoperative high-field MRI (Correlation coefficient, 0.677; P < 0.001). A significantly lower accuracy was identified with low-field iMRI in 6 cases with cavernous sinus invasion (33.3%) in contrast to the 87.8% found with other sites (Fisher's exact test, P < 0.001). The PoleStar N20 low-field iMRI navigation system is a promising tool for safe, minimally invasive, endonasal, transsphenoidal pituitary macroadenomas resection. It enables neurosurgeons to control the extent of tumor resection, particularly for suprasellar tumors, ensuring surgical accuracy and safety, and leading to a decreased likelihood of repeat surgeries. However, this technology is still not satisfying in estimating the amount of the parasellar residual tumor invading into cavernous sinus, given the false or uncertain images generated by low-field iMRI in this region, which are difficult to discriminate between tumor remnant and blood within the venous sinus.

The Pattern of Visual Impairment in Patients with Pituitary Adenoma

This retrospective study aimed to identify the pattern of visual impairment in pituitary adenoma patients. Patients' eyes were categorized into four groups according to their visual acuity score. Trans-sphenoidal hypophysectomy was performed on all patients. Significant differences between groups were evaluated for visual field defects, visual symptoms duration, degree of suprasellar extension and tumour pathology. In the 201 patients (402 eyes) evaluated, 166 eyes had impaired visual acuity (45 eyes, < 4.0; 43 eyes, 4.0 - 4.4; and 78 eyes, 4.5 - 4.8), 236 eyes scored > 4.8 and were considered to be free of this disorder. A linear correlation was found between visual field defects and visual acuity score. Duration of visual symptoms between visual acuity groups was not significant. Suprasellar extension (measured by Hardy grades) was significant between visual acuity groups and may be the main cause of visual acuity loss in pituitary adenoma patients. Non-functional pituitary adenomas tended to affect visual acuity more than adenomas with other pathological diagnoses which are adrenocorticotropic hormone and prolactin. Further investigation is required to clarify visual loss cause in pituitary adenoma patients.

Commentary

BACKGROUNDThe surgical treatment of pituitary adenomas in elderly patients (i.e., over 70 years of age) is a special problem because of the increased rate of perioperative complications and the reduced tolerance of postoperative fluid and electrolyte imbalance. Therefore, the unquestionable progress in the pharmacological and radiotherapy may not allow these patients the option of radical surgical treatment. We report our experience with the transsphenoidal procedure for pituitary adenomas in aged patients in an attempt to contribute to a better definition of the actual role of surgery.METHODSTranssphenoidal surgery was performed in 11 patients over 70 years of age affected by various histological types of pituitary micro- and macroadenomas, ranging from Hardy Grade I through IIIc. Special care was dedicated to the postoperative treatment, in particular to water and electrolyte balances, and to the immediate treatment of any pathological variation of these parameters.RESULTSWe had no mortality and no postoperative adjunctive morbidity. All the patients recovered well from the operation with an average hospital stay of 20 days. The tumor removal was complete in six cases and partial in the remaining five. With an average follow-up of 2 years, we did observe only one case of symptomatic recurrence of the disease.CONCLUSIONSTranssphenoidal surgery in the elderly is feasible and quite safe in the hands of an experienced team, if special care is devoted to the preoperative selection of patients and to the postoperative treatment of fluid and electrolyte imbalance.

Treatment of Pituitary Adenomas with a Transsphenoidal Approach

To evaluate the overall therapeutic effectiveness of transsphenoidal microsurgery for pituitary adenomas and explore the surgical technique, application of new technology, and postoperative follow-up. The clinical presentation, imaging features, endocrine examination, pathological types, conditions of operation, postoperative complications, and follow-up of 4050 patients with pituitary adenomas who had undergone transsphenoidal microsurgery from December 1981 to January 2004 were analyzed retrospectively. During the past 6 years, total tumor resection (under microscope) has been achieved in 97.3% of the patients with Hardy Grade I adenomas, 95.2% of Hardy Grade II, 90.4% of Hardy Grade III, and 47.4% of Hardy Grade IV. The percentages of total and subtotal resection achieved extended from 87.6% before 1987 to 96.9% in 2003. With the improvement of microsurgical technique and application of novel technology, the indications for transsphenoidal microsurgery for pituitary adenomas were increasingly extended. We believe that more than 90% of pituitary adenomas could be treated by the transsphenoidal approach and totally removed through the microscope. The transnasal perpendicular plate-sphenoid sinus approach will be the dominant mode. Routine postoperative radiotherapy is not required for patients with total resection.

Hydrocortisone dose and postoperative diabetes insipidus in patients undergoing transsphenoidal pituitary surgery: a prospective randomized controlled study

We report the results of a prospective randomized controlled trial, which looked at the incidence of postoperative diabetes insipidus (DI) following the use of three different hydrocortisone protocols, and the results of a study, on the incidence of DI and cortisol response in patients not given hydrocortisone. In study 1, 114 patients with pituitary macroadenoma were randomized into three groups: conventional dose (inj. hydrocortisone 100 mg IV 6-hourly for 3 days); intermediate dose (inj. hydrocortisone 100 mg IV 6-hourly on day 1, 100 mg IV 8-hourly on day 2, and 100 mg IV 12-hourly on day 3); low dose protocol (inj. hydrocortisone 25 mg IV 6-hourly on day 1, 25 mg IV 8-hourly on day 2 and 25 mg IV 12-hourly on day 3). Radical excision was achieved in 92 patients. The incidence of DI with the conventional dose was 52%, intermediate dose, 36% and low dose, 24% (p = 0.025). Study 2 included 16 consecutive patients with Hardy's grade A & B pituitary adenoma. These patients were randomized to receive (Group I) or not receive (Group II) hydrocortisone. Patients in Group II demonstrated normal cortisol response intraoperatively and no patient developed features of hypocortisolism; the incidence of DI in this group was 14%. The low dose hydrocortisone protocol reduced the incidence of DI by 46% when compared with the conventional dose hydrocortisone protocol. In patients with grade A and B tumour with normal preoperative cortisol levels, the use of perioperative hydrocortisone can be avoided.

The surgical treatment of pituitary adenomas in the eighth decade

BACKGROUND The surgical treatment of pituitary adenomas in elderly patients (i.e., over 70 years of age) is a special problem because of the increased rate of perioperative complications and the reduced tolerance of postoperative fluid and electrolyte imbalance. Therefore, the unquestionable progress in the pharmacological and radiotherapy may not allow these patients the option of radical surgical treatment. We report our experience with the transsphenoidal procedure for pituitary adenomas in aged patients in an attempt to contribute to a better definition of the actual role of surgery. METHODS Transsphenoidal surgery was performed in 11 patients over 70 years of age affected by various histological types of pituitary micro- and macroadenomas, ranging from Hardy Grade I through IIIc. Special care was dedicated to the postoperative treatment, in particular to water and electrolyte balances, and to the immediate treatment of any pathological variation of these parameters. RESULTS We had no mortality and no postoperative adjunctive morbidity. All the patients recovered well from the operation with an average hospital stay of 20 days. The tumor removal was complete in six cases and partial in the remaining five. With an average follow-up of 2 years, we did observe only one case of symptomatic recurrence of the disease. CONCLUSIONS Transsphenoidal surgery in the elderly is feasible and quite safe in the hands of an experienced team, if special care is devoted to the preoperative selection of patients and to the postoperative treatment of fluid and electrolyte imbalance.

The Transsphenoidal Removal of Nonfunctioning Pituitary Adenomas with Suprasellar Extensions

The surgical treatment of large pituitary adenomas with suprasellar extensions has been controversial. To elucidate the indications for transsphenoidal surgery of large adenomas and to evaluate the techniques for removing the suprasellar portions of the tumors, surgical procedures on 100 consecutive patients with suprasellar extensions of nonfunctioning pituitary adenomas were retrospectively investigated. Patients were followed up for 1 to 12 years (mean, 4.5 yr). One hundred twenty-five transsphenoidal operations were performed on 100 patients. The removal of each suprasellar tumor was facilitated by the placement of a lumbar subarachnoid catheter and the injection of lactated Ringer's solution or saline. This method was used in 77 operations and was effective on 60 of 72 adenomas with < 30-mm suprasellar extensions (Hardy's Grades A, B, and C) but not on those that were fibrous or dumbbell-shaped. The descent of the remaining suprasellar tumor was facilitated by keeping the sella and sellar floor open with an intrasellar drain, and the subsequent removal was achieved with staged transsphenoidal operations. Of nine fibrous or dumbbell-shaped adenomas with 10- to 30-mm suprasellar extensions, gross total removal in eight was achieved by the open sella technique and two-stage transsphenoidal operation, whereas one required transcranial surgery. Adenomas with > 30-mm suprasellar or lateral extensions (Grade D) could not be removed sufficiently by transsphenoidal operations, except one adenoma for which a subtotal removal was achieved in the third staged operation. The disease-free rate 10 years after operation was 74% for all patients: 91% for Grade A, 74% for Grade B, and 61% for Grade C.(ABSTRACT TRUNCATED AT 250 WORDS)

Factors in predicting outcome from operation in patients with prolactin-secreting pituitary adenomas.

Forty female patients with pituitary adenomas were studied retrospectively to determine whether factors could be identified that would help predict outcome from operation. Twenty-five patients had a normal prolactin level (less than or equal to 30 ng/ml) during the early postoperative period (less than or equal to 3 months) and 15 patients had persistent disease (prolactin greater than 30 ng/ml). Nine of the 25 patients who initially had normal prolactin levels during the early postoperative period were found to have elevated prolactin levels during the late postoperative period (greater than 3 months). As has been shown previously, tumor size and preoperative prolactin levels were important factors in predicting surgical outcome. Patients with smaller (Hardy Grades I and II) tumors had significantly better outcome than those with larger (Hardy Grades III and IV) tumors. Patients with successful surgical outcomes had significantly lower preoperative prolactin values (204 ng/ml) than those with operative failures (524 ng/ml). In addition to the known factors, the patient's age at the time of operation, the length of amenorrhea, and the patient's growth hormone response to insulin hypoglycemia were newly identified as factors that helped predict surgical outcome. Patients who were less than or equal to 26 years of age and who had had amenorrhea for less than or equal to 6 years at the time of operation had significantly better surgical outcomes. Patients with normal growth hormone responses to stimulation testing had significantly better surgical outcomes than those with a blunted preoperative growth hormone response. The data suggest that prolactin-secreting pituitary tumors may cause a progressive disorder for which operative cure may be obtained only early in the disease.