Olfactory improvement in acromegaly after transnasal transsphenoidal surgery

Effect of endoscopic endonasal skull base approaches on olfactory function and facial development in children

INTRODUCTION

Endoscopic approaches for skull base pathologies are increasingly being performed, and the subsequent complications, especially in the long term, have also been partially clarified. However, there is no information on the effects of endoscopic endonasal skull base surgeries (EESBS) in children on odor and facial development in parallel with long-term development. We conducted this study to investigate postoperative olfactory function and facial development in pediatric patients who underwent skull base surgery using the endoscopic endonasal method.

METHODS

We evaluated the smell test, sinonasal symptoms, and facial development of pediatric patients who underwent endoscopic endonasal skull base surgery after long-term follow-up. Odor was evaluated using the "Sniffin' Sticks" test kit, which assessed the T (odor threshold), D (odor discrimination), and I (odor identification) parameters. Sinonasal symptoms were evaluated using the SNOT-22 (sinus-nose outcome test) questionnaire. SNA (sella-nasion-A point), SNB (sella-nasion-B point), and ANB (A point-nasion-B point) angles were calculated from maxillofacial tomography and magnetic resonance imaging) to evaluate facial development. Data were compared with those of the healthy control group.

RESULTS

We included 30 patients comprising 19 (63.3%) boys and 11 (36.7%) girls, with no age difference between case and control groups. The mean follow-up period was 7 years. Odor test data, cephalometric measurements, and SNOT-22 analysis results showed no statistically significant differences between the two groups.

CONCLUSION

To our knowledge, this is a comprehensive study with the longest follow-up period in terms of evaluation of facial development after EESBS in children to analyze odor using the Sniffin' Sticks test kit and the quality of life using SNOT-22. Olfactory function, facial development, and quality of life remained unaffected after long-term follow-up after EESBS  in children. Although this surgical approach is minimally invasive, we recommend considering the possibility of complications, and the procedure should be performed by an experienced surgical team with adequate equipment.

Clinical study on the selection of endoscopes and microscopes for transsphenoidal surgery of non-aggressive pituitary macroadenoma and microadenoma and the influencing factors of hyposmia after endoscopic transsphenoidal surgery

Background and objective

Transsphenoidal surgery, including endoscopic and microscopic resection, is the first choice of treatment for pituitary tumors. With the widespread application of neuroendoscopy in recent decades, there has been a trend to replace microscopes. In clinical practice, we have found that in transsphenoidal surgery for non-invasive microadenomas and macroadenomas, microscopy can achieve a higher total resection rate, shorter operation time, lower incidence of postoperative complications, and faster recovery of olfaction. This study aimed to explore the selection of endoscopes and microscopes for non-aggressive transsphenoidal surgery for pituitary adenomas and the factors affecting olfactory recovery.

Methods

From August 2019 to October 2022, 93 patients with non-aggressive microadenomas and macroadenomas via the transsphenoidal approach were selected from the First Affiliated Hospital of Harbin Medical University and treated with rich experience in pituitary tumor subspecialty microscopy and endoscopic surgery. Different surgical methods were used to divide the patients into microscopic (n = 35) and endoscopic (n = 58) groups. The total tumor removal rate, intraoperative blood loss, operation time and cost, postoperative hospital stay, recovery of visual function, postoperative changes in hormone levels, complication rate, and recovery from complications 3 months after the operation were compared between the two groups.

Results

There were no significant differences in the tumor removal rate, postoperative visual acuity, and visual field recovery between the two groups (p > 0.05). There was a significant difference in the recovery rate of olfactory function between the two groups 3 months after the operation (p < 0.05), and there was no significant difference in the incidence of other complications (p > 0.05); Compared with the two groups, the microscope group had shorter operation time, longer postoperative hospital stay, less average operation cost and less blood loss, and the difference was statistically significant (p < 0.05). The position of the nasal septum mucosal flap incision was a risk factor for hyposmia 3 months after the operation.

Conclusion

Microsurgery and endoscopic surgery are suitable surgical treatments for nonaggressive microadenomas and macroadenomas. The total tumor removal and postoperative hormone remission rates of the two surgical methods were approximately the same. However, the microsurgery group had a shorter operation time, less intraoperative blood loss, faster olfactory function recovery, and a lower average operation cost. The position of the nasal septal mucosal flap incision was a risk factor for hyposmia at 3 months postoperatively. Hyposmia is less likely to occur when the superior edge of the nasal septal mucosal flap incision is not higher than the lower edge of the ipsilateral superior turbinate.

Long-term olfactory dysfunction after single-nostril endoscopic transnasal transsphenoidal pituitary adenoma surgery

BACKGROUND

Over the past decade, the endoscopic transnasal transsphenoidal approach for pituitary adenomas has been widely adopted among neurosurgeons. However, olfactory disturbances have been observed after this procedure, and few studies on long-term (>6 mo) olfactory disturbance after endoscopic transnasal transsphenoidal pituitary adenoma surgery have been conducted. Although we perform minimally invasive endoscopic surgery, some patients continue to experience hyposmia, with some even experience long-term hyposmia. This impairment results in a considerable loss in quality of life. We present a series of patients who underwent minimally invasive single-nostril TSS for pituitary adenoma, including evaluation of their olfactory function. We further investigated the related risk factors for long-term olfactory dysfunction.

METHODS

One hundred sixty-one consecutive patients who met the study criteria underwent the single-nostril endoscopic transsphenoidal approach by the senior author. The Smell Diskettes Olfaction Test was used to evaluate olfactory function.

RESULTS

Postoperative olfactory disturbance in patients treated with endoscopic transnasal TSS is frequent. Of the study population, 67.1% of the patients were hyposmic or anosmic and 14.9% had long-term olfactory dysfunction. We also performed multivariate logistic regression analysis to compare the characteristics of patients with long-term olfactory dysfunction. Nasal symptoms (odds ratio [OR], 6.77) and smoking (OR, 14.77) were associated with long-term olfactory dysfunction after transnasal TSS.

CONCLUSIONS

Significant disturbances in olfactory performance occur after single-nostril transnasal TSS for pituitary adenoma. Furthermore, preoperative nasal disease and smoking appear to be risk factors for long-term olfactory dysfunction. Physicians should address clinical findings related to olfactory function and provide appropriate care.

Olfactory outcomes after endonasal skull base surgery: a systematic review

For the last two decades, endonasal approach has been regularly applied to treat skull base lesions. However, postoperative olfactory dysfunction remains an unsolved problem. This systematic review aimed to identify factors that might affect postoperative olfactory prognosis of patients undergoing endonasal surgery for resection of sellar/parasellar lesions. The literature search was conducted comprehensively to exhaust studies which focused on patients' olfaction with objective olfactory assessments after endonasal skull base surgery. We sought to characterize the potential factors that might affect postoperative olfactory outcomes. Nineteen articles met inclusion criteria. We found that (1) endoscopic surgery was beneficial to patients' olfactory prognosis than microscopic surgery (incidence of postoperative decreased olfactory function: 18.48% (39/211) for the endoscopic group and 36.88% (52/141) for the microscopic group, P < 0.01); meta-analysis for single rate, 20% (95% CI 9-30%) for the endoscopic group and 35% (95% CI 0-72%) for the microscopic group); (2) harvesting septal flaps was an unfavorable factor for olfactory recovery and the rescue flap technique should be preferred compared with the HB flap; (3) no evidence showed that resection of the middle turbinate was detrimental to recovery of olfaction. Patients undergoing endoscopic endonasal surgery may have better olfactory outcomes than those undergoing microscopic endonasal surgery for resection of sellar/parasellar lesions. Special attention should be paid when using septal flaps is planned and the rescue flap technique should be the preferred choice. After resecting the middle turbinate, patients' olfaction still has a great chance of returning to the baseline. More homogeneous and high-quality studies are needed for further assessment.

Effect of Omega-3 Supplementation in Patients With Smell Dysfunction Following Endoscopic Sellar and Parasellar Tumor Resection: A Multicenter Prospective Randomized Controlled Trial

BACKGROUND

Endoscopic endonasal approaches pose the potential risk of olfactory loss. Loss of olfaction and potentially taste can be permanent and greatly affect patients' quality of life. Treatments for olfactory loss have had limited success. Omega-3 supplementation may be a therapeutic option with its effect on wound healing and nerve regeneration.

OBJECTIVE

To evaluate the impact on olfaction in patients treated with omega-3 supplementation following endoscopic skull base tumor resection.

METHODS

In this multi-institutional, prospective, randomized controlled trial, 110 patients with sellar or parasellar tumors undergoing endoscopic resection were randomized to nasal saline irrigations or nasal saline irrigations plus omega-3 supplementation. The University of Pennsylvania Smell Identification Test (UPSIT) was administered preoperatively and at 6 wk, 3 mo, and 6 mo postoperatively.

RESULTS

Eighty-seven patients completed all 6 mo of follow-up (41 control arm, 46 omega-3 arm). At 6 wk postoperatively, 25% of patients in both groups experienced a clinically significant loss in olfaction. At 3 and 6 mo, patients receiving omega-3 demonstrated significantly less persistent olfactory loss compared to patients without supplementation (P = .02 and P = .01, respectively). After controlling for multiple confounding variables, omega-3 supplementation was found to be protective against olfactory loss (odds ratio [OR] 0.05, 95% CI 0.003-0.81, P = .03). Tumor functionality was a significant independent predictor for olfactory loss (OR 32.7, 95% CI 1.15-929.5, P = .04).

CONCLUSION

Omega-3 supplementation appears to be protective for the olfactory system during the healing period in patients who undergo endoscopic resection of sellar and parasellar masses.

Olfactory bulb volume changes associated with trans-sphenoidal pituitary surgery

Objective

The trans-sphenoidal approach is most frequently used for pituitary adenoma (PA) enucleation. However, effects of this surgery on neighboring structures have received little attention so far. In particular, no investigations on olfactory bulb (OB) anatomy after trans-sphenoidal surgery have been reported. Because impairment of olfaction has been shown in small groups following trans-sphenoidal surgery we hypothesized that the transnasal approach is likely to alter OB volume which is associated with changes of olfactory function.

Methods

The study comprised 33 patients with pituitary adenoma (14 women and 19 men, mean age 50 years). Comprehensive assessment of olfactory function was conducted with the "Sniffin' Sticks" test kit. Based on magnetic resonance imaging scans OBs were measured before and approximately one year after trans-sphenoidal PA enucleation.

Results

Owing to postoperative non-compliance and MRI artifacts partly due to drill friction complete evaluation of “Sniffin' Sticks” in term of obtaining the TDI score was possible pre- and postoperatively in 21 patients whereas OB volumes were available in 32 patients. Approximately one year after surgery olfactory function was not significantly different from baseline. However, left- and right-sided OB volume in patients treated via trans-sphenoidal surgery decreased (p = 0.001). The side of the surgical approach did not affect OB volume in a side-specific manner. Changes in odor threshold were significantly correlated to changes in right-sided OB volume (r = 0.45, p = 0.024).

Conclusion

Overall olfactory performance one year after surgery was not significantly different from baseline. However, changes in OB volume are associated with changes in olfactory performance and OB volumes decreased in patients.

Preservation of Olfactory Function Following Endoscopic Single-Nostril Transseptal Transsphenoidal Surgery

OBJECTIVE

Olfactory dysfunction is a significant postoperative complication related to endoscopic transsphenoidal surgery (TSS). This study aimed to determine the impact of endoscopic TSS on olfactory function.

METHODS

We conducted a prospective study of 32 patients with sellar or parasellar tumors who were treated with endoscopic TSS between December 2013 and October 2016. TSS was performed via a right transseptal approach. We performed the Toyota and Takagi olfactometer test and the venous olfaction test for the evaluation of olfactory function preoperatively and at 1 and 3 months postoperatively.

RESULTS

The results of the Toyota and Takagi test showed that olfactory function deteriorated in 4 of 32 (12.5%) patients 1 month postoperatively and improved to preoperative baseline levels in all patients 3 months after the procedure. Olfactory function deteriorated in 1 of 31 (3.2%) patients 3 months after the procedure. The venous olfaction test revealed no response in 1 of 31 (3.2%) patients 1 month postoperatively, with no improvement 3 months after the procedure.

CONCLUSIONS

Endoscopic single-nostril transseptal TSS for sellar or parasellar tumor resection has minimal impact on olfactory function.

Olfactory Results of Endoscopic Endonasal Surgery for Pituitary Adenoma: A Prospective Study of 143 Patients

BACKGROUND

Clinical examination, including pre- and postoperative assessment of olfaction function, should be included in evaluating surgical outcomes in patients with pituitary adenomas. Most of the studies are lacking assessment of olfactory function.

METHODS

A prospective study of 143 patients who underwent surgical resection of pituitary adenomas from January 2014 to December 2017 was performed. Data on clinical presentation, pre- and postoperative neurologic, endocrinologic, and ophthalmologic examinations, complications, and follow-up outpatient examinations were recorded. Olfactory function was assessed using the Sniffin' Sticks odor identification test preoperatively, postoperatively (3 months), and 1 year after surgery.

RESULTS

Normosmia was present preoperatively in 93.7% of patients, postoperatively in 95.8% of patients, and in 95.1% 1 year postsurgery. Hyposmia was present preoperatively in 4.2% of patients, postoperatively in 2.1% of patients, and in 1.4% 1 year after surgery. Anosmia was present preoperatively in 2.1% of patients, postoperatively in 2.1% of patients, and in 3.5% 1 year after surgery. In patients with preoperative normosmia, postoperative hyposmia and anosmia were present in 1.5% of patients. There were no differences according to age, sex, size, or type of pituitary adenoma.

CONCLUSIONS

Assessment of olfactory function should be included in the analysis of pituitary adenoma surgery results. This prospective study showed low risk of olfaction deterioration if an endoscopic endonasal approach is used without any mucosal flaps for skull base reconstruction. Further studies that include objective olfaction assessment are warranted.

Olfactory function in patients after transsphenoidal surgery for pituitary adenomas-a short review

Olfaction is an important sensory input that obviously affects many daily activities. However, olfactory dysfunction (hyposmia and anosmia) leads to a pronounced decrease in quality of life. Surprisingly, little attention has been paid to olfactory changes after transsphenoidal surgery for pituitary tumors. In this review, we summarize current knowledge of the effects of transsphenoidal pituitary surgery on olfaction and compare different surgical techniques. Based on selected studies, the endoscopic approach, in comparison with the microscopic approach, seems to be superior in terms of preservation of olfactory function, although the quality of data from these studies is generally poor. The best results were observed when the endoscopic approach was used without harvesting of the nasoseptal flap.

Auditory changes in acromegaly

OBJECTIVE

The aim of this study is to determine the changes involving auditory system in cases with acromegaly.

MATERIALS AND METHODS

Otological examinations of 41 cases with acromegaly (uncontrolled n = 22, controlled n = 19) were compared with those of age and gender-matched 24 healthy subjects. Whereas the cases with acromegaly underwent examination with pure tone audiometry (PTA), speech audiometry for speech discrimination (SD), tympanometry, stapedius reflex evaluation and otoacoustic emission tests, the control group did only have otological examination and PTA. Additionally, previously performed paranasal sinus-computed tomography of all cases with acromegaly and control subjects were obtained to measure the length of internal acoustic canal (IAC).

RESULTS

PTA values were higher (p < 0.001 for right ears and p = 0.001 for left ears), and SD scores were (p = 0.002 for right ears and p = 0.002 for left ears) lower in acromegalic patients. IAC width in acromegaly group was narrower compared to that in control group (p = 0.03 for right ears and p = 0.02 for left ears). When only cases with acromegaly were taken into consideration, PTA values in left ears had positive correlation with growth hormone and insulin-like growth factor-1 levels (r = 0.4, p = 0.02 and r = 0.3, p = 0.03). Of all cases with acromegaly 13 (32%) had hearing loss in at least one ear, 7 (54%) had sensorineural type and 6 (46%) had conductive type hearing loss.

CONCLUSION

Acromegaly may cause certain changes in the auditory system in cases with acromegaly. The changes in the auditory system may be multifactorial causing both conductive and sensorioneural defects.

Periodic olfactory assessment in patients undergoing skull base surgery with preservation of the olfactory strip

OBJECTIVES/HYPOTHESIS

Others have reported olfactory disturbances following endoscopic approaches to the skull base. However, there is a lack of consensus on the extent and duration of dysfunction. This study aimed to compare our results with previously published work and to validate the olfactory strip-sparing approach.

STUDY DESIGN

Prospective study to assess olfaction in 50 patients scheduled to undergo resection of skull base tumors via extended endoscopic approaches.

METHODS

Patients were divided into two groups. Group I had a nasoseptal flap (NSF), and group II included patients in whom rescue flaps were performed bilaterally. Olfactory outcomes were assessed using repeated University of Pennsylvania Smell Identification Test at baseline, 6 weeks, 3 months, and 6 months following surgery.

RESULTS

Ultimately, 42 patients (seven group I and 35 group II) were available for assessment. Scores for group I were lower than at baseline at 6 weeks postoperatively (30.71 ± 5.5 vs. 24.5 ± 5.4; P = .05). However, by the third postoperative month the scores had improved to a level that was not significantly different from baseline (29.0 ± 3.7; P = .5). At 6 months, the score was 30.0 ± 3.9. Patients in group II showed no difference between their baseline and 6-week scores (31.5 ± 5.3 vs. 29.7 ± 5.9; P = .16). Six months postoperatively, the score was significantly higher (33.78 ± 3.6; P = .04).

CONCLUSIONS

Expanded endoscopic approaches to skull base tumors involving reconstruction with an NSF are associated with a short-term negative impact on olfaction. Olfaction does not seem to be affected by the surgical resection of pituitary adenomas associated with rescue flaps. Identification of the olfactory epithelium and meticulous harvesting of the NSF are critical to preserve olfaction.

LEVEL OF EVIDENCE

4. Laryngoscope, 127:1970-1975, 2017.

Transient Exacerbation of Nasal Symptoms following Endoscopic Transsphenoidal Surgery for Pituitary Tumors: A Prospective Study

Object  Endoscopic transsphenoidal surgery is the commonest approach to pituitary tumors. One disadvantage of this approach is the development of early postoperative nasal symptoms. Our aim was to clarify the peak onset of these symptoms and their temporal evolution. Methods  The General Nasal Patient Inventory (GNPI) was administered to 56 patients undergoing endoscopic transsphenoidal surgery for pituitary tumors preoperatively and at 1 day, 3 days, 2 weeks, 3 months, and 6 to 12 months postoperatively. Most patients underwent surgery for pituitary adenomas ( N  = 49; 88%) and through a uninostril approach ( N  = 55; 98%). Total GNPI (0-135) and scores for the 45 individual components were compared. Results  GNPI scores peaked at 1 to 3 days postoperatively, with rapid reduction to baseline by 2 weeks and below baseline by 6 to 12 months postsurgery ( p  < 0.01). Of the 45 individual symptoms on the GNPI scale, 19 (42%) worsened transiently after surgery ( p  < 0.05). Functioning tumors had a higher GNPI scores at postoperative day 1 and 3 than nonfunctioning tumors, although their temporal evolution was the same ( p  < 0.05). Conclusions  Nasal morbidity following endoscopic transsphenoidal pituitary surgery is common, but transient, more so in the functioning subgroup. Nasal symptoms improve below baseline by 6 to 12 months, without the need for specific long-term postoperative interventions in the vast majority of patients.

Objective assessment of olfaction after transsphenoidal pituitary surgery

BACKGROUND

Transnasal endoscopic pituitary surgery has proven to be a safe and effective method for removing pituitary tumors. Direct and angled endoscopy at the site of dissection provides excellent visualization without external incisions. However, olfactory loss has been documented after surgical approaches to the pituitary and is accompanied by a significant detriment to quality of life.

STUDY DESIGN

A prospective cohort study.

METHODS

Subjects 19 years and older who were undergoing transnasal endoscopic pituitary surgery were recruited for this study. The University of Pennsylvania Smell Identification Test (UPSIT) was administered preoperatively and then at 3-4 months. Data regarding demographics, reconstructive technique, and complications were recorded. The patients had skull-base reconstruction with a Medpore implant or a vascularized nasoseptal flap.

RESULTS AND DISCUSSION

A total of 33 subjects were recruited, with 18 completing the study. The mean (SEM) age was 58.2 ± 2.4 years, with 12 females and 6 males. The majority of patients (89%) had nonfunctioning macroadenomas, and six individuals had reconstruction by using a vascularized nasoseptal flap. Matched mean (SEM) preoperative and postoperative UPSIT scores for this cohort were not significantly different (31.3 ± 0.4 versus 30.5 ± 0.5, respectively; p = 0.54). In addition, there was no significant difference between the mean preoperative and postoperative UPSIT scores of the patients who had nasoseptal flaps (29.4 ± 1.1 vs. 28.6 ± 1.3 respectively; p = 0.87).

CONCLUSIONS

In the current study, pre- and postoperative UPSIT scores were not significantly different in patients who underwent endoscopic transnasal pituitary surgery. The use of a nasoseptal flap also did not adversely affect postoperative UPSIT scores.

Endoscopic Endonasal Anterior Skull Base Surgery: A Systematic Review of Complications During the Past 65 Years

BACKGROUND

Endoscopic skull base surgery is becoming more popular as an approach to the anterior skull base for tumors and cerebrospinal fluid (CSF) fistulae. It offers the advantages of better cosmesis and improved quality of life after surgery. We reviewed the complication rates reported in the literature.

METHODS

A literature search was performed in the electronic database Ovid MEDLINE (1950 to August 25, 2015) with the search item "([Anterior] AND Skull base surgery) AND endoscopic."

RESULTS

We identified 82 relevant studies that included 7460 cases. An average overall complication rate of 17.1% (range 0%-68.0%) and a mortality rate of 0.4% (0%-10.0%) were demonstrated in a total of 82 studies that included 7460 cases. The average CSF leak rate for all studies was 8.9% (0%-40.0%) with meningiomas and clival lesions having the greatest CSF leak rates. The most frequent benign pathology encountered was pituitary adenomas (n = 3720, 49.8% of all cases) and the most frequent malignant tumor was esthesioneuroblastoma (n = 120, 1.6% of all cases). Studies that included only CSF fistula repairs had a lower average total complication rate (12.9%) but a greater rate of meningitis compared with studies that reported mixed pathology (2.4% vs. 1.3%). A trend towards a lower total complication rate with increasing study size was observed.

CONCLUSIONS

The endoscopic approach is an increasingly accepted technique for anterior skull base tumor surgery and is associated with acceptable complication rates. Increasing experience with this technique can decrease rates of complications.

Impairment of olfaction and mucociliary clearance after expanded endonasal approach using vascularized septal flap reconstruction for skull base tumors

BACKGROUND

Endoscopic skull base surgery is now the preferred treatment option to remove skull base tumors.

OBJECTIVE

To evaluate the patient's sense of smell and mucociliary clearance time (MCT) after skull base surgery.

METHODS

Patients with pituitary adenoma underwent a transnasal transsphenoidal endoscopic approach (TTEA group, n = 36), whereas patients with other benign parasellar tumors underwent an expanded endonasal approach (EEA group, n = 14) with a vascularized septal flap. Assessment of symptoms (Visual Analogue Scale), olfactometry (Barcelona Smell Test, BAST-24), and MCT (saccharin test) were performed before and 3 months after surgery.

RESULTS

Before surgery, patients reported poorer BAST-24 scores on detection, identification, and forced choice than the healthy population, but both study groups had similar sinonasal symptoms, BAST-24, and MCT scores. After surgery, no changes in symptom scores (Visual Analogue Scale) were observed except for the loss of smell (26.7 ± 30.5 mm, P < .05) and posterior nasal discharge (29.7 ± 30.3 mm, P < .05) compared with baseline (5.2 ± 11.3, 19.1 ± 25.3, respectively). EEA patients reported higher loss of smell and posterior nasal discharge compared with TTEA. TTEA and EEA groups had similar scores on postoperative BAST-24. After surgery, however, patients showed prolonged saccharin test (15.6 ± 10.8 min, P < .05) compared with baseline (8.4 ± 4.4 min). In addition, EEA patients reported longer MCT than TTEA patients.

CONCLUSION

EEA but not TTEA has a short-term (3 months) negative impact on patient's olfaction and mucociliary clearance. Patients should be informed about smell loss as a consequence of skull base surgery to prevent legal claims. Likewise, further research and some modifications on reconstruction flaps are encouraged to avoid damaging the olfactory neuroepithelium.