Intracranial internal carotid artery changes in acromegaly: a quantitative magnetic resonance angiography study

Anatomical variations of the cavernous Internal Carotid Artery: Validation of an MRI-based classification

OBJECTIVE

Variations of the cavernous Internal Carotid Artery (ICA) angulation (C4-bend) have been classified into 4 anatomical subtypes with particular surgical relevance, as a very angulated ICA comes in closest contact with the pituitary gland leading to higher risk of iatrogenic vascular injury. This study aimed to validate this classification using current routine imaging techniques.

METHODS

The different cavernous ICA bending angles were measured on 109 MRI TOF sequences, within a retrospective database of patients with no sellar lesions. Each ICA was classified into one of 4 anatomical subtypes as already defined in a previous study [1]. Interrater agreement was assessed by a Kappa Correlation Coefficient.

RESULTS

Kappa Correlation Coefficient was of 0.90 [0.82-0.95], validating the strong level of agreement between all observers when using the present classification.

CONCLUSION

Classification of the cavernous ICA in 4 subtypes appears statistically valid on routinely used pre-operative MRI, providing an efficient tool to estimate the vascular iatrogenic risk prior to endoscopic endonasal transsphenoidal surgery.

Sellar Remodeling after Surgery for Nonfunctioning Pituitary Adenoma: Intercarotid Distance as a Predictor of Recurrence

Introduction  As they grow, pituitary adenoma can remodel the sella turcica and alter anatomical relationships with adjacent structures. The intercarotid distance (ICD) at the level of the sella is a measure of sella width. The purpose of this study was to (1) assess how ICD changes after transsphenoidal surgery and (2) explore whether the extent of ICD change is associated with tumor recurrence. Methods  A retrospective analysis of preoperative and postoperative coronal magnetic resonance imaging (MRI) scans was carried out by two independent assessors on patients who underwent transsphenoidal surgery for nonfunctioning pituitary macroadenomas. Preoperative tumor volume and any change in ICD following surgery were recorded and compared between groups. Logistic regression models of recurrence were generated. Results  In 36 of 42 patients, ICD fell after surgery (mean = 1.8 mm) and six cases were static. At time of follow-up (mean = 77 months), 25 had not required further intervention and 17 had undergone second surgery or radiosurgery. In patients in whom no further intervention has yet been necessary, the postoperative reduction in ICD was significantly smaller than in those who required repeat intervention (1.1 vs. 2.7 mm respectively, p  < 0.01). ICD decrease was weakly correlated with tumor volume ( r  = 0.35). ICD decrease was a significant predictor of recurrence (odds ratio [OR] = 3.15; 95% confidence interval [CI]: 1.44-6.87), largely independent of tumor volume. Conclusion  For most patients, ICD falls following surgical excision of a nonfunctioning pituitary macroadenoma. A greater reduction in ICD postsurgery appears to predict recurrence. Change in ICD shows promise as a radiographic tool for prognosticating clinical course after surgery.

Morphometric Alterations of the Sphenoid Ostium and other Landmarks in Acromegaly: Anatomical Considerations and Implications in Endoscopic Pituitary Surgery

Background

The sphenoid ostium (SO) is an important landmark for the endoscopic surgeon. Changes in size and position of the SO and variations in other skull base landmarks in acromegalics have not been adequately evaluated.

Aims

The authors evaluated the morphometry and location of the SO and other landmarks in acromegaly and compared these findings with those in nonfunctioning pituitary adenomas (NFPAs).

Methods

In this retrospective case-control study, the dimensions and location of the SO and other skull base landmarks were radiologically evaluated in 18 patients with growth hormone (GH)-secreting adenomas. These findings were analyzed in relation to preoperative GH levels and compared with 18 age- and sex-matched controls with NFPAs.

Results

The dimensions of the SO were significantly larger in the GH-adenoma group (P < 0.05). The SO was further from the midline (P = 0.04) and closer to the sphenopalatine foramen (SPF) (P = 0.02) in the GH-adenoma group, and this finding correlated with increasing preoperative GH levels. Acromegalics demonstrated larger intracavernous carotid diameters (P = 0.05) and smaller intercarotid distances than the patients with NFPAs (P = 0.02).

Conclusion

The SO is larger and located higher up in the sphenoid face and closer to the SPF in patients with GH adenomas. Increasing GH levels in these patients correlate with the upward and lateral displacement of the SO. These patients demonstrate larger intracavernous carotid diameters and smaller intercarotid distances than patients with NFPAs. These morphological alterations are of particular relevance to the pituitary surgeon.

Italian Association of Clinical Endocrinologists (AME) and Italian AACE Chapter Position Statement for Clinical Practice: Acromegaly - Part 1: Diagnostic and Clinical Issues

Acromegaly is a rare disease. Improvements in lifespan in these patients have recently been reported due to transsphenoidal surgery (TSS), advances in medical therapy, and strict criteria for defining disease remission. This document reports the opinions of a group of Italian experts who have gathered together their prolonged clinical experience in the diagnostic and therapeutic challenges of acromegaly patients. Both GH and IGF-I (only IGF-I in those treated with Pegvisomant) are needed in the diagnosis and follow-up. Comorbidities (cardio-cerebrovascular disease, sleep apnea, metabolic derangement, neoplasms, and bone/joint disease) should be specifically addressed. Any newly diagnosed patient should be referred to a multidisciplinary team experienced in the treatment of pituitary adenomas.

The Change in Distance Between Bilateral Internal Carotid Arteries in Acromegaly and Its Risk Factors

Background: Studies investigating the change in distance between the bilateral internal carotid arteries (ICAs) in acromegalic patients have provided ambiguous results. The influencing factors of these changes have not been well-identified. Objective: To further investigate the change in distance between bilateral ICAs in acromegaly patients and identify the influencing factors of the change. Method: Patients diagnosed as acromegaly from Jan 2016 to Sep 2019 in the Department of Neurosurgery of the First Affiliated Hospital of Fujian Medical University, were included in this study. Computed tomography angiography (CTA) or magnetic resonance angiography (MRA) data were obtained for all patients for three-dimensional reconstruction of the ICAs. Distance between bilateral ICAs was measured and recorded for assessment. Result: 172 patients including 86 cases with acromegaly in the study group and 86 cases with non-functional pituitary adenoma in the control group were enrolled in this study. The difference of adenoma sizes between two groups was not statistically significant. Patients in acromegaly group had significantly larger maximum distances between bilateral siphon carotid ectasias (25.5 ± 4.1 vs. 23.4 ± 3.5 mm, P = 0.001) and between bilateral lacerum segments (26.2 ± 3.2 vs. 24.1 ± 4.3 mm, P < 0.001) compared with those of patients with non-functional pituitary adenomas. Multivariate analysis showed that the increased bilateral ICAs distance was associated with disease duration (odds ratio = 1.01, 95% confidence interval = 1.01-1.02, P = 0.005) and refractory pituitary adenoma (odds ratio = 9.8, 95% confidence interval = 1.1-88.7, P = 0.043) but not with level of growth hormone (GH), insulin-like growth factor-1 (IGF-1) and adenoma size in acromegaly. Conclusion: Our study showed significant change in distance between the bilateral ICAs in acromegalic patients, comparing to patients with non-functional pituitary adenomas. The increased intercarotid artery distance is associated with disease duration but not with preoperative level of GH and IGF-1. Refractory pituitary adenoma and longer disease duration are the both risk factors of the increased ICAs distance in patient with acromegly.

Radiotherapy in acromegaly: Long-term brain parenchymal and vascular magnetic resonance changes

BACKGROUND

Radiation therapy (RT) effectiveness on hormonal reduction is proven in acromegaly; however, collateral long-term effects are still undetermined. This transversal neuroimaging study on a large cohort of acromegalic patients aimed to investigate the rate of parenchymal and vascular changes after RT.

MATERIALS AND METHODS

Thirty-six acromegalic patients underwent RT (RT+) after unsuccessful surgery and were compared to RT- acromegalic patients matched for age, gender, adenoma features, clinical and surgical history. All patients underwent magnetic resonance angiography (MRA) to investigate intracranial artery abnormalities and FLAIR sequence to assess white matter changes according to the Wahlund scale.

RESULTS

RT+ acromegalic patients had a higher rate of controlled disease (29/36 vs. 12/36, P<0.001). RT+ acromegalic patients had MRI/MRA evaluation 15.3±9.6 years after RT. RT+ acromegalic patients had a significantly higher Wahlund score than RT- acromegalic patients (6.03±6.41 vs. 2.53±3.66, P=0.006) due to increased white matter signal abnormalities at the level of the temporal lobes, the basal ganglia (insula) and the infratentorial regions, bilaterally. Among RT+ patients one died because of temporo-polar anaplastic astrocytoma, one suffered from a stroke due to right internal carotid artery occlusion, one presented with cystic degeneration of the temporal poles. Long-dated RT (>10 years before MR evaluation) was associated with a higher rate of RT-related white matter changes (P=0.0004).

CONCLUSIONS

RT seems to have created a cohort of patients with brain parenchymal changes whose clinical and cognitive impact is still unknown. These patients might require a prolonged MRI and MRA follow-up to promptly detect delayed RT-related complications and minimize their clinical consequences.

The changing sella: internal carotid artery shift during transsphenoidal pituitary surgery

PURPOSE

Injuries to the internal carotid artery (ICA) are potentially lethal complications in transsphenoidal surgery (TSS) for pituitary lesions. The intercarotid distance (ICD) is thus a major parameter, determining the width of the surgical corridor in TSS. The purpose of the study is to investigate changes in ICD at different levels of the ICA during and after TSS using high definition intraoperative MRI (3T-iMRI).

METHODS

Pre-, intra- and 3 months postoperative MRI images of 85 TSS patients were reviewed. ICD was measured at the horizontal (ICDC4h) and vertical (ICDC4v) intracavernous C4 segment as well as at the C6 segment (ICDC6). Association between ICD change at different levels and time points were compared and potential factors predicting ICD reduction were analyzed.

RESULTS

ICD decreased intraoperatively at all three segments of ICA by -3% (median decreases: ICDC4h: -0.5 mm, ICDC4v: -0.7 mm ICDC6: -0.4 mm). At 3 months postoperative MRI, ICD reduced by a further -4%, -2% and -4% respectively (median decreases ICDC4h: -0.7, ICDC4v: -0.4 mm, ICDC6: -0.5 mm). Postoperative narrowing in ICD occurred independent of further resection after 3T-iMRI. ICD change correlated between different levels of the ICA indicating a uniform shift perioperatively. Preoperative ICD was significantly associated with the intraoperative reduction in ICDC4v and ICDC6.

CONCLUSIONS

We have demonstrated a uniform narrowing in ICD at different levels of the ICA during and after TSS adenoma resection. Surgeons should be aware of this change since it determines the width of the surgical corridor and can thus influence the ease of surgery.

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.

Basilar Artery Changes in Fabry Disease

BACKGROUND AND PURPOSE

Dolichoectasia of the basilar artery is a characteristic finding of Fabry disease. However, its prevalence, severity, and course have been poorly studied. This study quantitatively evaluated, by MRA, a panel of basilar artery parameters in a large cohort of patients with Fabry disease.

MATERIALS AND METHODS

Basilar artery mean diameter, curved length, "origin-to-end" linear distance (linear length), and tortuosity index ([curved length ÷ linear length] - 1) were retrospectively measured on 1.5T MRA studies of 110 patients with Fabry disease (mean age, 39.4 ± 18.6 years; 40 males) and 108 control patients (mean age, 42.0 ± 18.2 years; 40 males).

RESULTS

Patients with Fabry disease had increased basilar artery mean diameter (P < .001) and basilar artery linear length (P = .02) compared with control patients. Basilar artery curved length and tortuosity index correlated with age in both groups (P < .001), whereas basilar artery linear length correlated with age only in patients with Fabry disease (P = .002). Patients with Fabry disease showed a basilar artery curved length mean increase of 4.2% (9.7% in male patients with Fabry disease versus male control patients), whereas the basilar artery mean diameter had a mean increase of 12.4% (14.3% in male patients with Fabry disease versus male control patients). Male patients with Fabry disease had increased basilar artery mean diameter, curved length, and tortuosity index compared with female patients with Fabry disease (P = .04, P = .02, and P < .001, respectively) and male control patients (P < .001, P = .01, and P = .006, respectively). Female patients with Fabry disease demonstrated an age-dependent increase of basilar artery mean diameter that became significant (P < .001) compared with female control patients above the age of 45 years.

CONCLUSIONS

The basilar artery of patients with FD is subjected to major remodeling that differs according to age and sex, thus providing interesting clues about the pathophysiology of cerebral vessels in Fabry disease.

Does MMP-9 Gene Polymorphism Play a Role in Pituitary Adenoma Development?

Purpose. To determine if the MMP-9 genotype has an influence on development of pituitary adenoma (PA). Methodology. The study enrolled n = 86 patients with PA and n = 526 healthy controls (reference group). The genotyping of MMP-9 was carried out using the real-time polymerase chain reaction method. Results. Our data demonstrated that the MMP-9 (–1562) C/C genotype was more frequent in PA group than in healthy controls (81.4% versus 64.6%, p = 0.002); C/C genotype was more frequently present in PA females compared to healthy control females, 81.5% versus 64.6%, p = 0.018, as well. MMP-9 (–1562) C/C genotype was frequently observed for all subgroups: noninvasive and invasive, nonrecurrence, and inactive PA compared to healthy controls: 81.8% versus 64.6%, p = 0.021; 81.0% versus 64.6%, p = 0.041; 81.8% versus 64.6%, p = 0.005; 100.0% versus 64.6%, p < 0.001, respectively. MMP-9 (–1562) C/C genotype was more frequent in inactive PA compared to active PA: 100.0% versus 71.4%; p < 0.001. Conclusion. MMP-9 (–1562) C/C genotype plays a role in nonrecurrence, inactive, and invasive as well as in nonivasive PA development.

Carotid artery protrusion and dehiscence in patients with acromegaly

PURPOSE

Acromegaly is a systemic disease which causes multiple bony alterations. Some authors reported that acromegalic patients have risk factors for an intraoperative vascular injury due to the specific anatomical features of their sphenoid sinus. The objective of our study was to analyze the anatomic characteristics of sphenoid sinus in acromegalic patients compared with controls, by evaluation of computed tomography (CT) findings.

METHODS

We examined 45 acromegalic (acromegaly group) and 45 non-acromegalic patients (control group) with pituitary adenomas who were matched for sex, age, height, tumor size, and cavernous sinus invasion (Knosp grade). Preoperative CT of the pituitary region including the sphenoid sinus was used to evaluate the following anatomic characteristics: type of sphenoid sinus (sellar or pre-sellar/conchal); intrasphenoid septa (non/single or multiple); carotid artery protrusion; carotid artery dehiscence; intercarotid distance.

RESULTS

Sixteen acromegalic patients (35.5 %) and 6 controls (13.3 %) had carotid artery protrusion. Additionally, 10 acromegalic patients (22.2 %) and 3 controls (6.6 %) had carotid artery dehiscence. Carotid artery protrusion and dehiscence were more frequent in the acromegaly group than in control group (p = 0.013 and 0.035, respectively). Other anatomic characteristics (type of sphenoid sinus, intrasphenoid septa, and intracarotid distance) showed no significant differences between acromegaly and control groups.

CONCLUSIONS

Our study suggests that carotid artery protrusion and dehiscence occur more frequently among acromegalic patients, compared with non-acromegalic patients. It is important for surgeons to be aware of these anatomic variations to avoid vital complications, such as carotid injuries, during surgery.

Effect of Hypoxia on DDR1 Expression in Pituitary Adenomas

Background

Pituitary adenoma is a common intracranial tumor in neurosurgery. Some pituitary adenomas have the characteristics of invasive growth make them unable to be removed completely by surgery leading to easy relapse. Discoidin domain receptor l (DDR1) is a new kind of tyrosine kinase receptor on the cell surface. DDR1 can be activated by tumor microenvironment signal in tumorigenesis, increasing MMP-2/9 expression and promoting the invasive ability of tumor cells. Anoxia can promote tumor growth and metastasis. This study investigated the impact of anoxic environment DDR1 expression in pituitary adenoma.

Material/Methods

A primary hypoxia pituitary adenoma cell model was established and treated with DDR1 inhibitor nilotinib. Real-time PCR and Western blot were used to detect DDR1 mRNA and protein expression. ELISA was used to detect MMP-2/9 changes. MTT method was used to detect pituitary adenoma cell proliferation. We used a transwell chamber to determine pituitary adenoma cell invasion ability.

Results

DDR1 mRNA and protein were significantly overexpressed under hypoxia (P<0.05). MMP-2 and MMP-9 expression was obviously increased in supernatant (P<0.05). Pituitary adenoma cell proliferation and invasive ability improved markedly under hypoxia (P<0.05). Nilotinib could reduce DDR1 expression, decrease MMP-2 and MMP-9 expression, and inhibit pituitary adenoma cells proliferation and invasion.

Conclusions

Hypoxia can increase DDR1 expression in pituitary adenoma cells, leading to improved MMP-2 and MMP-9 secretion, and promoting pituitary adenoma cell proliferation and invasion.

Expression of cold-inducible RNA-binding protein (CIRP) in pituitary adenoma and its relationships with tumor recurrence

BACKGROUND

The aim of this study was to detect the expression of cold-inducible RNA-binding protein in pituitary adenoma and to determine its effects on tumor recurrence.

MATERIAL/METHODS

We collected a total of 60 post-op samples collected from pituitary adenoma patients (including 20 cases of invasive pituitary adenoma, 20 cases of non-invasive adenoma, and 20 cases of non-invasive recurrent adenoma) admitted in our hospital. Both protein and mRNA levels of CIRP in 3 types of pituitary adenoma samples were quantified by Western blotting and real-time PCR, respectively.

RESULTS

Western blotting revealed significantly elevated CIRP expression levels in invasive pituitary adenoma compared to non-invasive tumors, with statistical significance (p<0.05). Recurrent pituitary adenoma expressed significantly higher CIRP levels compared to non-recurrent tumors (p<0.05). Real-time PCR for CIRP mRNA obtained consistent results: transcript levels were significantly higher in invasive pituitary adenoma compared to non-invasive adenoma (p<0.05); recurrent adenoma also had significantly higher CIRP mRNA levels compared to non-recurrent tumors (p<0.05). Among all 3 types of pituitary adenoma, recurrent tumors had the highest levels of CIRP mRNA and protein.

CONCLUSIONS

The expression of CIRP in pituitary adenoma is closely related with tumor proliferation and invasion, and its significantly elevated expression level indicates post-op recurrence.