Growth hormone increase by luteinizing hormone-releasing hormone reflects gonadotroph-related characteristics in acromegaly.

PURPOSE: We previously showed the clinical characteristics of acromegaly with a paradoxical growth hormone (GH) response to oral glucose or thyrotropin-releasing hormone. However, the clinical characteristics of acromegaly with an increased GH response to luteinizing hormone-releasing hormone (LHRH responders) remain unclear. The aim of the present study was to evaluate the clinical characteristics, especially gonadotroph-related characteristics of LHRH responders in acromegaly. METHODS: The clinical characteristics of 33 LHRH responders and 81 LHRH nonresponders were compared. RESULTS: No differences in age, sex or basal serum levels of GH, insulin-like growth factor-1 (IGF-1), and gonadotropin were observed between the two groups. Steroidogenic factor 1 (SF-1), gonadotropin-releasing hormone receptor (GnRHR), and LH expression was more frequently observed in LHRH responders (P < 0.05). In addition, a greater increased rate of GH after LHRH loading, and the proportion of GnRHR and gonadotropin expression was observed in pituitary tumor with SF-1 expression than that without the expression (P < 0.01). LHRH responders showed a greater GH decrease in the octreotide test and a greater IGF-1 decrease after first-generation somatostatin ligand than LHRH nonresponders (P < 0.05). Furthermore, the proportion of hypointense pituitary tumors on T2-weighted magnetic resonance imaging and tumors with densely granulated type was higher in LHRH responders than in LHRH nonresponders, respectively (P < 0.05). No difference between the two groups was observed in either somatostatin receptor 2 or 5 expression. CONCLUSIONS: The increased GH response to LHRH is associated with the gonadotroph-related characteristics. This response may reflect the biological characteristics of somatotroph tumors.

Appearance of fluid content in Rathke's cleft cyst is associated with clinical features and postoperative recurrence rates.

PURPOSE: The contents of Rathke's cleft cysts (RCCs) vary from clear and slightly viscous to purulent. Surgical treatment of symptomatic RCCs involves removing the cyst contents, whereas additional cyst-wall opening to prevent reaccumulation is at the surgeon's discretion. The macroscopic findings of the cyst content can reflect the nature of RCCs and would aid in surgical method selection. METHODS: We retrospectively reviewed the records of 42 patients with symptomatic RCCs who underwent transsphenoidal surgery at our institute between January 2010 and March 2022. According to the intraoperative findings, cyst contents were classified into type A (purulent), type B (turbid white with mixed semisolids), or type C (clear and slightly viscous). Clinical and imaging findings and early recurrence rate (within two years) were compared according to the cyst content type. RESULTS: There were 42 patients classified into three types. Patients with type C were the oldest (65.4 ± 10.4 years), and type A included more females (92.9%). For magnetic resonance imaging, type-A patients showed contrast-enhanced cyst wall (92.9%), type-B patients had intracystic nodules (57.1%), and all type-C patients showed low T1 and high T2 intensities with larger cyst volumes. Fewer asymptomatic patients had type C. Preoperative pituitary dysfunction was most common in type A (71.4%). Early recurrence was observed in types A and C, which were considered candidates for cyst-wall opening. CONCLUSION: The clinical characteristics and surgical prognosis of RCCs depend on the nature of their contents.

[Electrocorticography Recorded from Subdural Electrodes and Stereo-Electroencephalography].

Epilepsy surgeons often encounter drug-resistant focal epilepsy, which needs to be diagnosed so that the epileptic foci can be identified and the patient treated. When noninvasive preoperative evaluation cannot determine the region of seizure onset or eloquent cortical areas, invasive epileptic video-EEG monitoring using intracranial electrodes needs to be applied. While subdural electrodes have been used to accurately identify epileptogenic foci via electrocorticography for some time, the use of stereo-electroencephalography has recently exploded in Japan, due to its less invasive nature and its better ability to reveal epileptogenic networks. This report describes the underlying concepts, indications, procedures, and contributions to neuroscience of both surgical procedures.

Analgesic Effects of Repetitive Transcranial Magnetic Stimulation at Different Stimulus Parameters for Neuropathic Pain: A Randomized Study.

OBJECTIVES: The aim of the present study was to investigate the analgesic effects of repetitive transcranial magnetic stimulation over the primary motor cortex (M1-rTMS) using different stimulation parameters to explore the optimal stimulus condition for treating neuropathic pain. MATERIALS AND METHODS: We conducted a randomized, blinded, crossover exploratory study. Four single sessions of M1-rTMS at different parameters were administered in random order. The tested stimulation conditions were as follows: 5-Hz with 500 pulses per session, 10-Hz with 500 pulses per session, 10-Hz with 2000 pulses per session, and sham stimulation. Analgesic effects were assessed by determining the visual analog scale (VAS) pain intensity score and Short-Form McGill Pain Questionnaire 2 (SF-MPQ2) score immediately before and immediately after intervention. RESULTS: We enrolled 22 adults (age: 59.8 ± 12.1 years) with intractable neuropathic pain. Linear-effects models showed significant effects of the stimulation condition on changes in VAS pain intensity (p = 0.03) and SF-MPQ2 (p = 0.01). Tukey multiple comparison tests revealed that 10-Hz rTMS with 2000 pulses provided better pain relief than sham stimulation, with greater decreases in VAS pain intensity (p = 0.03) and SF-MPQ2 (p = 0.02). CONCLUSIONS: The results of this study suggest that high-dose stimulation (specifically, 10-Hz rTMS at 2000 pulses) is more effective than lower-dose stimulation for treating neuropathic pain.

[Stereotactic Surgery for Tremor].

Although tremor is one of the most common movement disorders, there are many different types, and proper diagnosis is important for appropriate treatment. Action tremor has a significant impact on daily life, but the effectiveness of medical treatment is insufficient, and surgery is often the treatment of choice. Surgical treatment is effective in suppressing tremor, and a large percentage of tremors can be adequately controlled. Currently available surgical treatments for tremor include the ventral intermediate nucleus of thalamus-deep brain stimulation(DBS), radiofrequency(RF)-thalamotomy, focused ultrasound(FUS)-thalamotomy, and gamma knife thalamotomy. DBS is often considered the first choice for surgical treatment due to the number of past cases in which DBS has been applied, reported evidence, long-term efficacy, safety, adjustability, and the possibility of bilateral treatment, but RF-thalamotomy is also expected to improve efficacy and safety because of recent advancements in coagulation technology and the accumulation of anatomical knowledge regarding the target nucleus. In addition, the number of cases in which FUS-thalamotomy has been applied has been increasing in the past few years due to its minimally invasive nature, which does not require puncture of the brain. As neurosurgeons, we have the responsibility to select and perform appropriate surgical treatment based on sufficient knowledge of tremor to yield beneficial results in patients.

Jarvik 2000 with postauricular cable as destination therapy: first clinical case in Japan.

Currently in Japan, a left ventricular assist device powered by an abdominal driveline is the only type of left ventricular assist device available. The driveline is vulnerable to infection secondary to inappropriate fixation and the traditional Japanese custom of bathing is prohibited in patients with an abdominal driveline. The Jarvik 2000 with postauricular cable is a left ventricular assist device in which the driveline exits the body behind the ear (postauricular) instead of exiting through an abdominal site. This case report is the first to describe the implantation of Jarvik 2000 with postauricular cable as destination therapy in a Japanese patient. This device enables patients to take a bath and may reduce the incidence of driveline infection.

Clinical significance of screening for subclinical Cushing's disease in patients with pituitary tumors.

Cushing's syndrome (CS) is a clinical state caused by chronic excess of glucocorticoid, and results in hypertension, impaired glucose tolerance, and dyslipidemia. Recently, a mild state of pituitary CS without typical Cushingoid appearance (subclinical Cushing's disease; SCD) has been identified. However, the true prevalence of SCD and its effect on metabolic disorders remain obscure. The aim of this prospective study was to determine the prevalence of SCD according to the guideline proposed by the working group of the Japanese Ministry of Health, Welfare and Labor, and to assess the outcome of surgery on metabolic disorders. The prevalence of SCD was investigated in 105 consecutive patients diagnosed with pituitary adenomas by MRI. ACTH-dependent hypercortisolism was diagnosed based on the results of the 0.5 mg dexamethasone suppression test (serum cortisol >3.0 µg/dL) plus one positive finding of the following two tests: midnight serum cortisol level >5.0 µg/dL or ACTH increase >50% after 1-deamino-5-D-arginine vasopressin (DDAVP) challenge. The final diagnosis of SCD was established by positive staining for ACTH in surgically-excised pituitary adenoma. Three patients (4.8%) were diagnosed with SCD among 62 patients with pituitary adenoma. Transsphenoidal adenomectomy partially resulted in improvement of blood pressure and glucose metabolism in SCD patients. Our results emphasize the importance of SCD screening in patients with pituitary tumors, especially in those patients with metabolic disorders.

Nur77 gene expression levels were involved in different ACTH-secretion autonomy between Cushing's disease and subclinical Cushing's disease.

Cushing's disease (CD) and subclinical Cushing's disease (subCD) are both diseases caused by adrenocorticotropic hormone (ACTH)-secreting pituitary adenomas. However, ACTH autonomy in subCD is weaker than in CD and there are no Cushingoid features in subCD. The differences of molecular mechanisms in ACTH autonomy between CD and subCD have not yet been reported. Therefore, we aimed to investigate the differences in molecular mechanisms of ACTH-secretion autonomy between CD and subCD. The study included 23 patients [7 CD, 6 subCD, and 10 non-functioning pituitary tumors (NFTs)] who underwent transsphenoidal surgery at the Osaka University Hospital between December 2009 and October 2013. Using quantitative real-time PCR, various ACTH-related gene expressions in tumor tissues from CD, subCD, and NFT were measured such as pro-opiomelanocortin (POMC), POMC transcription factor (Tpit, Pitx1, NeuroD1, and Nur77), POMC peptide processing enzymes (prohormone convertase: PC1/3 and PC2), and ACTH secretion-related factors (corticotropin-releasing hormone receptor 1: CRHR1 and glucocorticoid receptor α: GRα). Only Nur77 mRNA levels were significantly higher in CD than in subCD. Furthermore, we stained 6 CD and 6 subCD with anti-Nur77 antibody. All tumor samples from CD had Nur77 protein positive cells. On the other hand, Nur77 protein was expressed in only one tumor sample from subCD. This sample showed high expression of Nur77 mRNA. Nur77 is an important to regulate POMC transcription and negative-feedback by glucocorticoids. Nur77 gene expression levels might involve different autonomy of ACTH production between CD and subCD.

Respiratory Function Under Intrathecal Baclofen Therapy in Patients With Spastic Tetraplegia.

OBJECTIVES: Intrathecal baclofen (ITB) therapy is an effective treatment for patients with severe spasticity. However, the effect of ITB therapy on respiratory function has not been reported in detail. In this study we quantitatively analyzed the effects of ITB on the respiratory function of patients with spastic tetraplegia. METHODS: We retrospectively reviewed 23 patients who were administrated ITB therapy from January 2009 to December 2012. Six of these 23 patients, who had spastic tetraplegia and were able to undergo spirometric testing, were included this study. The spasticity derived from cervical spinal cord injury in four patients and cerebral palsy (CP) in two patients. Patients' Ashworth Scale scores and spirometer measurements obtained before and 1-6 months after the start of ITB therapy were evaluated and compared. RESULTS: Before ITB therapy, %FVC of all six patients was below 80%, and a restrictive respiratory disorder was diagnosed in five patients and a combined respiratory disorder in one patient. Ashworth Scale scores for both the lower and upper extremities improved significantly with ITB therapy. Forced vital capacity (FVC), %FVC, and forced expiratory volume at one sec also improved significantly with ITB therapy. CONCLUSIONS: Respiratory disorders were indeed present in our SCI and CP patients with spastic tetraplegia, and the respiratory function of these patients improved with ITB therapy. Our results suggest that ITB therapy is safe and efficacious in patients with spastic tetraplegia and respiratory dysfunction.

Olfactory sphere cells are a cell source for γ-aminobutyric acid-producing neurons.

Olfactory sphere cells (OSCs) are stem cells generated by culturing olfactory mucosa. Adult rat OSCs express oligodendrocyte progenitor cell (OPC) markers and differentiate into mature oligodendrocytes. Although OSCs also express nestin, a marker of neural stem cells (NSCs), it remains unclear whether adult rat OSCs are multipotent and capable of giving rise to neurons as well as oligodendrocytes. Valproic acid (VPA) is a histone deacetylase inhibitor that has the contradictory capacity to induce both differentiation of NSCs and dedifferentiation of OPCs. This study investigates a potential role for VPA in inducing either differentiation or dedifferentiation of adult rat OSCs. Treatment of OSCs with VPA induced hyperacetylation of histones and decreased cell proliferation in the absence of changes in the number of nestin-positive cells. Furthermore, VPA promoted the genesis of γ-aminobutyric acid (GABA)-producing neurons identified by expression of Tuj1/GAD67/GABA while repressing oligodendrocyte production. These findings suggest that OSCs treated with VPA did not exhibit stem cell properties indicative of dedifferentiation but rather switched to a neuronal identity during their terminal differentiation. OSCs were then transplanted into the hippocampus of rats with kainic acid-induced temporal lobe epilepsy and were systemically given VPA. Although grafted OSCs expressed Tuj1 and GAD67, these cells did not sufficiently inhibit epileptic activity. These results suggest that OSCs are a transplantable cell source for GABA-producing neurons that can be modulated by VPA. However, further investigation is required to develop them for clinical applications.

Postoperative changes in bone metabolism and bone mineral density in Japanese patients with acromegaly: a 3-year prospective study.

Growth hormone and insulin-like growth factor-I play important roles in regulating bone metabolism and bone mineral density in adulthood. However, the effect of excess growth hormone on bone metabolism and bone mineral density is not fully understood. Here, we investigated the long-term changes in bone metabolism and bone mineral density after a rapid decline in growth hormone levels due to transsphenoidal surgery in acromegalic patients. Eighteen acromegalic patients (10 males and 8 females) who underwent transsphenoidal surgery were enrolled in this prospective study. Bone formation marker (serum bone alkaline phosphatase), bone resorption marker (urinary type I collagen cross-linked N-telopeptide), and bone mineral density were measured before surgery and at 3 months, 1 year, and 3 years after transsphenoidal surgery. While both serum bone alkaline phosphatase and urinary type I collagen cross-linked N-telopeptide levels decreased significantly after surgery, serum bone alkaline phosphatase/urinary type I collagen cross-linked N-telopeptide ratio was significantly increased at 3 months and 3 years after surgery. Bone mineral density did not change markedly after surgery. In conclusion, the rapid decline in growth hormone levels following transsphenoidal surgery had no marked effect on bone mineral density for up to 3 years, despite significant changes in levels of bone turnover makers post-surgery.

Gsp mutation in acromegaly and its influence on TRH-induced paradoxical GH response.

OBJECTIVE: We recently reported that paradoxical GH response to TRH administration reflects biological characteristics in patients with acromegaly. The aim of this study is to elucidate the relationship between gsp mutations and the paradoxical GH response to TRH. PATIENTS: Sixty-seven patients with acromegaly were included for analysis. Paradoxical increase in serum GH level to TRH, GH suppression by octreotide and bromocriptine, radiological profiles and histopathological findings were analysed with respect to tumour gsp-mutation status. RESULTS: Twenty-six (38·8%) gsp mutations were detected, and the number of paradoxical GH responders to TRH, defined as an increase of 100% or more in GH after TRH, was 49 (73·1%). Among the paradoxical GH responders to TRH, 21 patients (42·9%) had a gsp mutation and 28 patients (57·1%) did not. The percentage of paradoxical GH responders to TRH in gsp-positive and gsp-negative patients was not significantly different (80·8% and 68·3%, respectively). The gsp-positive group showed a significantly higher paradoxical increase in serum GH level by TRH administration (1830% vs 650% GH increase, P = 0·045) and greater GH suppression by octreotide (88·7% vs 75·4% GH decrease, P = 0·003) than the gsp-negative group. CONCLUSION: Paradoxical GH response to TRH was observed regardless of gsp mutation, although the rate of increase was significantly higher in gsp-positive patients. These results suggest that gsp mutation is not sufficient to cause the paradoxical GH response to TRH, while other unidentified factors have a strong influence on paradoxical GH response to TRH in patients with acromegaly.

Low-frequency subthalamic nucleus stimulation in Parkinson's disease: a randomized clinical trial.

BACKGROUND: Low-frequency, bilateral stimulation of the subthalamic nucleus can improve axial symptoms of advanced Parkinson's disease (PD), but it is not particularly effective for segmental symptoms. METHODS: The optimal contacts for low-frequency (60 Hz) and high-frequency (130 Hz) single monopolar stimulation were determined. Then, in a randomized, double-blind, prospective crossover manner, 60-Hz and 130-Hz stimulations via the respective optimal contacts were compared for immediate efficacy in improving the motor function of patients with PD. RESULTS: The optimal contacts for 60-Hz stimulation were situated more ventrally than those for 130-Hz stimulation (P = 0.038). Under the respective optimal, single monopolar stimulation, 60 Hz provided superior efficacy over 130 Hz in improving the total Unified Parkinson's Disease Rating Scale motor score (P < 0.001) and the akinesia (P = 0.011) and axial motor signs (P = 0.012) subscores without compromising the therapeutic effect on tremor and rigidity. CONCLUSIONS: Low-frequency stimulation via the optimal contacts is effective in improving overall motor function of patients with PD.

Rapid decline in bone turnover markers but not bone mineral density in acromegalic patients after transsphenoidal surgery.

Growth hormone (GH) and insulin-like growth factor-I (IGF-I) play important roles in maintaining bone metabolism and bone mineral density (BMD) in adulthood, in addition to stimulating longitudinal bone growth in childhood. However, information on the effect of GH excess on bone metabolism and BMD is incomplete and requires further analysis. The aim of this study is to clarify the effect of rapid decline in GH levels after transsphenoidal surgery (TSS) on bone metabolism in acromegalic patients. In this prospective study, 22 patients (11 males and 11 females) with active acromegaly underwent TSS. Bone formation marker (serum bone alkaline phosphatase: BAP), bone resorption marker (urinary type I collagen cross-linked N-telopeptide: urinary NTx) and BMD were measured before and at 3 and 12 months after TSS. BAP was significantly decreased at 12 months after TSS, but not at 3 months. Urinary NTx was significantly decreased at 3 and 12 months after TSS. BMD did not change after TSS. In conclusion, the rapid fall in GH level after TSS had no effect on BMD for up to 12 months after TSS despite the decrease in markers of bone formation and resorption.

Hippocampal sharp-wave ripples correlate with periods of naturally occurring self-generated thoughts in humans.

Core features of human cognition highlight the importance of the capacity to focus on information distinct from events in the here and now, such as mind wandering. However, the brain mechanisms that underpin these self-generated states remain unclear. An emerging hypothesis is that self-generated states depend on the process of memory replay, which is linked to sharp-wave ripples (SWRs), which are transient high-frequency oscillations originating in the hippocampus. Local field potentials were recorded from the hippocampus of 10 patients with epilepsy for up to 15 days, and experience sampling was used to describe their association with ongoing thought patterns. The SWR rates were higher during extended periods of time when participants' ongoing thoughts were more vivid, less desirable, had more imaginable properties, and exhibited fewer correlations with an external task. These data suggest a role for SWR in the patterns of ongoing thoughts that humans experience in daily life.

Repetitive transcranial magnetic stimulation focusing on patients with neuropathic pain in the upper limb: a randomized sham-controlled parallel trial.

This study aimed to evaluate the efficacy and safety of navigation-guided repetitive transcranial magnetic stimulation (rTMS) over the primary motor cortex in patients with neuropathic pain in the upper limb. This randomized, blinded, sham-controlled, parallel trial included a rTMS protocol (10-Hz, 2000 pulses/session) consisting of five daily sessions, followed by one session per week for the next seven weeks. Pain intensity, as well as pain-related disability, quality of life, and psychological status, were assessed. For the primary outcome, pain intensity was measured daily using a numerical rating scale as a pain diary. Thirty patients were randomly assigned to the active rTMS or sham-stimulation groups. In the primary outcome, the decrease (least square [LS] mean ± standard error) in the weekly average of a pain diary at week 9 compared to the baseline was 0.84 ± 0.31 in the active rTMS group and 0.58 ± 0.29 in the sham group (LS mean difference, 0.26; 95% confidence interval, - 0.60 to 1.13). There was no significant effect on the interaction between the treatment group and time point. Pain-related disability score improved, but other assessments showed no differences. No serious adverse events were observed. This study did not show significant pain relief; however, active rTMS tended to provide better results than sham. rTMS has the potential to improve pain-related disability in addition to pain relief.Clinical Trial Registration number: jRCTs052190110 (20/02/2020).

Accuracy of Boltless Frame-Based Stereo-Electroencephalography Electrode Implantation.

BACKGROUND AND OBJECTIVES: Boltless implantation of stereo-electroencephalography electrode is a useful alternative especially when anchor bolt is not available such as in country with limited resources or is less appropriate such as placement in patients with thin skull or at the occiput area, despite some drawbacks including potential dislodgement. While the accuracy of implantation using anchor bolt is well-studied, data on boltless implantation remain scarce. This study aimed to reveal the accuracy, permissible error for actual placement of electrodes within the grey matter, and delayed electrode dislodgement in boltless implantation. METHODS: A total of 120 electrodes were implanted in 15 patients using a Leksell Stereotactic G Frame with each electrode fixed on the scalp using sutures. Target point error was defined as the Euclidean distance between the planned target and the electrode tip on immediate postimplantation computed tomography. Similarly, delayed dislodgement was defined as the Euclidean distance between the electrode tips on immediate postimplantation computed tomography and delayed MRI. The factors affecting accuracy were evaluated using multiple linear regression. The permissible error was defined as the largest target point error that allows the maximum number of planned gray matter electrode contacts to be actually placed within the gray matter as intended. RESULTS: The median (IQR) target point error was 2.6 (1.7-3.5) mm, and the permissible error was 3.2 mm. The delayed dislodgement, with a median (IQR) of 2.2 (1.4-3.3) mm, was dependent on temporal muscle penetration (P = 5.0 × 10-4), scalp thickness (P < 5.1 × 10-3), and insertion angle (P = 3.4 × 10-3). CONCLUSION: Boltless implantation of stereo-electroencephalography electrode offers an accuracy comparable to those using anchor bolt. During the planning of boltless implantation, target points should be placed within 3.2 mm from the gray-white matter junction and a possible delayed dislodgement of 2.2 mm should be considered.

Text and image generation from intracranial electroencephalography using an embedding space for text and images.

Objective.Invasive brain-computer interfaces (BCIs) are promising communication devices for severely paralyzed patients. Recent advances in intracranial electroencephalography (iEEG) coupled with natural language processing have enhanced communication speed and accuracy. It should be noted that such a speech BCI uses signals from the motor cortex. However, BCIs based on motor cortical activities may experience signal deterioration in users with motor cortical degenerative diseases such as amyotrophic lateral sclerosis. An alternative approach to using iEEG of the motor cortex is necessary to support patients with such conditions.Approach. In this study, a multimodal embedding of text and images was used to decode visual semantic information from iEEG signals of the visual cortex to generate text and images. We used contrastive language-image pretraining (CLIP) embedding to represent images presented to 17 patients implanted with electrodes in the occipital and temporal cortices. A CLIP image vector was inferred from the high-γpower of the iEEG signals recorded while viewing the images.Main results.Text was generated by CLIPCAP from the inferred CLIP vector with better-than-chance accuracy. Then, an image was created from the generated text using StableDiffusion with significant accuracy.Significance.The text and images generated from iEEG through the CLIP embedding vector can be used for improved communication.

Prevalence of cerebral aneurysm in patients with acromegaly.

The prevalence of cerebral aneurysm was retrospectively investigated in 208 patients with acromegaly relative to the rate of cerebral aneurysm in a group of control subjects. Neuroradiological examinations of the cerebral vascular system were conducted in 208 acromegaly patients (101 men; mean age, 48.8 years). The prevalence of cerebral aneurysm in the acromegaly patients was compared to that in a control group consisting of 7,390 subjects who underwent "brain checkup" between 2006 and 2008 (mean age, 51.6 years). In the acromegaly group, cerebral aneurysm was detected in 4.3 % of patients. By sex, the prevalence was 6.9 % in males, a significantly proportion than that in the control group with an odds ratio of 4.40. The prevalence in females did not differ between the two groups. In the acromegaly group, the rate of hypertension was significantly higher in the patients with aneurysm compared to those without aneurysm. Multiple logistic regression identified acromegaly as a significant factor related to the prevalence of cerebral aneurysm in all male subjects; other factors, such as age, hypertension and smoking, were not found to be significant. A significantly higher prevalence of cerebral aneurysm was detected in male patients with acromegaly. This finding indicates that excess growth hormone or insulin-like growth factor 1 affects the cerebral vascular wall, resulting in aneurysm formation. In addition to known systematic complications in the cardiovascular, respiratory, metabolic, and other systems, the risk of cerebral aneurysm should be considered in the management of acromegaly.

Characteristics of Pain During MRI-Guided Focused Ultrasound Thalamotomy.

BACKGROUND: Magnetic resonance imaging-guided focused ultrasound (MRgFUS) has become popular as an incisionless mode of neurosurgical treatment. However, head pain during sonication is common and its pathophysiology remains poorly understood. OBJECTIVE: To explore the characteristics of head pain occurring during MRgFUS thalamotomy. METHODS: Our study comprised 59 patients who answered questions about the pain they experienced during unilateral MRgFUS thalamotomy. The location and features of pain were investigated using a questionnaire including the numerical rating scale (NRS) to estimate maximum pain intensity and the Japanese version of the Short Form of McGill Pain Questionnaire 2 to evaluate the quantitative and qualitative dimensions of pain. Several clinical factors were investigated for possible correlation with pain intensity. RESULTS: Forty-eight patients (81%) reported sonication-related head pain, and the degree of pain was severe (NRS score ≥ 7) in 39 patients (66%). The distribution of sonication-related pain was "localized" in 29 (49%) and "diffuse" in 16 (27%); the most frequent location was the "occipital" region. The pain features most frequently reported were those in the "affective" subscale of the Short Form of McGill Pain Questionnaire 2. Patients with diffuse pain had a higher NRS score and lower skull density ratio than did patients with localized pain. The NRS score negatively correlated with tremor improvement at 6 months post-treatment. CONCLUSION: Most patients in our cohort experienced pain during MRgFUS. The distribution and intensity of pain varied according to the skull density ratio, indicating that the pain might have had different origins. Our results may contribute to the improvement of pain management during MRgFUS.