Custom fabricated three-dimensional printed surgical guide for trephine bur in autogenous bone graft: A technique report.

This technique presents a workflow that designs the custom surgical guide to cover a trephine bur using simple slicer software and three-dimensional (3D) printing to perform the semilunar technique. This method in autogenous bone grafting surgery harvests a thin layer of cortical bone in the donor site with a trephine bur. Its biologically favorable, round shape can be used as a shell to reconstruct the ridge with a 3D contour acceptable for future implant placement. A 78-year-old female patient required vertical and horizontal bone grafting for future implant placement due to the infection caused by the vertically fractured root of a premolar. The patient's cone beam computed tomography (CBCT) file was translated into a standard tessellation language (STL) file, and recipient and donor site models were created. Simulated surgery was done using the software first to detect any possible complications during surgery. The trephine bur planned for use in surgery was measured in necessary dimensions, and the values were added to create a guide for surgery in slicer software. Then, it was 3D-printed with a stereolithography (SLA) printer. After testing the fit of the guide, it was further tested on a fused filament fabrication (FFF) printed donor site model to check if the desired shape and size of the plate were acquired after harvest. Then, the plates were used for model surgery on the recipient site model. After no issues from the previous steps, the final patient surgery was approved and completed with success. This technique utilizes the SLA printing method to create the custom surgical guide for a trephine bur without using commercially available products. Moreover, it could be tested on FFF 3D-printed anatomical models to ensure its validity. With this innovative technique, clinicians can efficiently perform a semilunar technique, facilitating the surgery and improving patient care.

Main issues in penetrating keratoplasty.

This review explores contemporary challenges in penetrating keratoplasty (PK), focusing on technical intricacies, technological advancements, and strategies for preventing graft rejection. A systematic literature search from January 2018 to July 2023 was conducted across PubMed, Cochrane, Web of Science, Scopus, and EMBASE. The inclusion criteria comprised studies on PK and its comparison with other corneal pathologies, with emphasis on keratoconus (KC). Two independent reviewers screened studies, extracting relevant data. The review covers PK evolution, highlighting infra-red femtosecond lasers' impact on graft shapes, minimizing astigmatism, and enhancing wound healing. Graft rejection, a primary complication, is examined, detailing risk factors and preventive measures. Preoperative considerations, diagnostic techniques for rejection, and PK in KC are discussed. Postoperative care's significance, including intraocular pressure monitoring and steroid administration, is emphasized. The paper concludes with a comprehensive approach to prevent graft rejection, involving topical and systemic medications. An outlook on evolving monoclonal antibody research is presented. As the field progresses, personalized approaches and ongoing therapeutic exploration are expected to refine strategies, enhancing PK outcomes.

Safe and time-saving treatment method for acute cerebellar infarction: Navigation-guided burr-hole aspiration - 6-years single center experience.

OBJECTIVE: While patients with medically intractable acute cerebellar infarction typically undergo suboccipital craniectomy and removal of the infarcted tissue, this procedure is associated with long operating times and postoperative complications. This study aimed to investigate the effectiveness of minimally invasive navigationguided burr hole aspiration surgery for the treatment of acute cerebellar infarction. METHODS: Between January 2015 and December 2021, 14 patients with acute cerebellar infarction, who underwent navigation-guided burr hole aspiration surgery, were enrolled in this study. RESULTS: The preoperative mean Glasgow Coma Scale (GCS) score was 12.7, and the postoperative mean GCS score was 14.3. The mean infarction volume was 34.3 cc at admission and 23.5 cc immediately following surgery. Seven days after surgery, the mean infarction volume was 15.6 cc. There were no surgery-related complications during the 6-month follow-up period and no evidence of clinical deterioration. The mean operation time from skin incision to catheter insertion was 28 min, with approximately an additional 13 min for extra-ventricular drainage. The mean Glasgow Outcome Scale score after 6 months was 4.8. CONCLUSIONS: Navigation-guided burr hole aspiration surgery is less time-consuming and invasive than conventional craniectomy, and is a safe and effective treatment option for acute cerebellar infarction in selected cases, with no surgery-related complication.

Balancing Bleeding Risk and Thromboembolic Complications in Elderly Chronic Subdural Hematoma Patients Undergoing Burr Hole Trephination : A Multicenter Retrospective Cohort Study and Literature Review.

OBJECTIVE: Chronic subdural hematoma (CSDH) patients using antithrombotic agents (AT) at high risk for cardiovascular disease are increasing. The authors aimed to analyze the factors influencing outcome by targeting patients using AT and to establish a desirable treatment strategy. METHODS: A retrospective analysis was performed on data from 462 patients who underwent burr hole trephination (BHT) surgery for CSDH at five hospitals from March 2010 to June 2021. Outcomes included incidence of postoperative acute bleeding, recurrence rate, and morbidity or mortality rate. Patients were divided into the following four groups based on their history of AT use : no AT. Only antiplatelet agents (AP), only anticoagulants (AC), both of AP and AC. In addition, a concurrent literature review was conducted alongside our cohort study. RESULTS: Of 462 patients, 119 (119/462, 25.76%) were using AT. AP prescription did not significantly delay surgery (p=0.318), but AC prescription led to a significant increase in the time interval from admission to operation (p=0.048). After BHT, AP or AC intake significantly increased the period required for an in-dwelling drain (p=0.026 and p=0.037). The use of AC was significantly related to acute bleeding (p=0.044), while the use of AP was not (p=0.808). Use of AP or AC had no significant effect on CSDH recurrence (p=0.517 and p=1.000) or reoperation (p=0.924 and p=1.000). Morbidity was not statistically correlated with use of either AP or AC (p=0.795 and p=0.557, respectively), and there was no significant correlation with mortality for use of these medications (p=0.470 and p=1.000). CONCLUSION: Elderly CSDH patients may benefit from maintenance of AT therapy during BHT due to reduced thromboembolic risk. However, the use of AC necessitates individualized due to potential postoperative bleeding. Careful post-operative monitoring could mitigate prognosis and recurrence impacts.

Preventing cerebral spinal fluid leakage following endoscopy through a burr hole using a novel watertight closure: technical note.

BACKGROUND: Cerebrospinal fluid (CSF) leakage is a common complication after neuroendoscopic surgery through a burr hole and can lead to further complications including infection. METHODS: We describe the use of a dural substitute larger than the burr hole itself, placed over the burr hole and then secured underneath a burr hole cover by microscrews running through the graft itself into the underlying skull. RESULTS: This simple technical modification contributes to achieving a watertight seal to aid in preventing CSF leakage in this setting. CONCLUSIONS: Our technical modification of endoscopy through a burr hole may help to prevent postoperative CSF leak and secondary CSF infections.

Rapid Spontaneous Resolution of Contralateral Lentiform Acute Subdural Hematoma After Burr Hole Trephination for Chronic Subdural Hematoma.

Although rare, acute subdural hematoma (ASDH) may occur after burr hole trephination (BHT) for chronic subdural hematoma (CSDH). It usually occurs in the hemisphere ipsilateral to the burr hole site and rarely in the hemisphere contralateral to the burr hole site. On computed tomography (CT), SDH is usually crescent-shaped and occasionally lentiform or biconvex, which can be misdiagnosed as epidural hematoma (EDH). In rare cases, ASDH may resolve spontaneously and rapidly. Here, we report a case of rapid spontaneous resolution of contralateral lentiform ASDH after BHT for CSDH in a patient with brain atrophy. A 55-year-old man developed left CSDH 2 months after traumatic brain injury. Left BHT was performed, and a lentiform hematoma, presumed to be EDH, was found in the right frontal region on the CT scan acquired immediately after BHT. On the CT scan acquired 12 hours later, the lentiform hematoma disappeared and spread along the hemisphere. It was presumed to be ASDH. To prevent contralateral ASDH after BHT, slow decompression and minimal gentle or no irrigation should be performed during BHT, particularly in patients with brain atrophy.

Uso de la embolización de la arteria meníngea media en recidiva de hematoma subdural crónico / Use of embolization of the middle meningeal artery in chronic subdural hematoma recurrence

RESUMEN El hematoma subdural crónico (HSDC) es una patología neuroquirúrgica frecuente, con una recurrencia de hasta el 30% de los casos. La embolización de la arteria meníngea media (AMM) es una estrategia de manejo adyuvante para disminuir la recidiva, especialmente en pacientes con factores de riesgo para recurrencia, y tiene una baja tasa de complicaciones. Presentamos el caso de un varón de 83 años con antecedente de anticoagulación, que es admitido en centro sanitario por presentar hemiparesia derecha, disartria y alteración de la marcha, con un tiempo de enfermedad de una semana. Se realizó trepanación y evacuación del HSDC sin complicaciones. Un mes después retornó por recidiva del HSDC, por lo que se realizó trepanación y evacuación adecuada del HSDC, seguida de embolización de la AMM ipsilateral. El control a los dos meses mostró ausencia de recidiva, con mejoría neurológica del paciente. Concluimos que la embolización de la AMM fue un tratamiento adyuvante eficaz para disminuir la recidiva del HSDC y podría estar indicada en pacientes con factores de riesgo asociados a la recurrencia.

ABSTRACT Chronic subdural hematoma (CSDH) is a frequent neurosurgical condition, which may develop recurrence in up to 30% of all cases. Embolization of the middle meningeal artery (MMA) is an adjuvant management strategy for reducing recurrence, especially in patients with risk factors, and it has a low complication rate. We present the case of an 83-year old male with history of anticoagulation, who was admitted in a healthcare facility because of right hemiparesis, dysarthria and gait impairment, and he had been sick for one week. A trepanation and CSDH evacuation were uneventfully performed. One month later, the patient was brought back because of CSDH recurrence, so another trepanation and adequate CSDH evacuation were performed, followed by embolization of the ipsilateral MMA. A control assessment after two months revealed absence of recurrence and neurological improvement. We conclude that MMA embolization was an efficacious adjuvant therapy aiming to reduce CSDH recurrence, and this procedure may be indicated in patients with risk factors for recurrence.

Burr Hole Drainage versus Small Craniotomy of Chronic Subdural Hematomas.

OBJECTIVE: Chronic subdural hematoma drainage is one of the most common procedures performed in neurosurgical practice. Not only burr hole drainage but also small craniotomy (diameter 3-5 cm) is frequently used neurosurgical treatment of chronic subdural hematomas. We assessed to compare the postoperative recurrence rates between burr hole drainage versus small craniotomy with closed-system drainage for chronic subdural hematomas. METHODS: From January 2016 to December 2018, 75 patients who were treated with burr hole drainage and small craniotomy with closed system drainage for the symptomatic chronic subdural hematoma were enrolled. Pre and postoperative computed tomography (CT) were used for radiologic evaluation. The choice of procedure was decided by preoperative CT images. RESULTS: 60 patients out of 75 patients underwent burr hole drainage, whereas 15 patients underwent small craniotomy. The overall postoperative recurrence rate was 16%. The recurrence occurred in 8 patients out of 60 patients in burr hole drainage group (13.3%) and 7 patients out of 15 patients in small craniotomy group (46.7%). The number of days of hospitalization was 10.3 days in burr hole drainage group and 15.7 days in small craniotomy group. CONCLUSION: Burr hole drainage would be sufficient to evacuate chronic subdural hematoma with lower recurrence rate, but small craniotomy was also needed in some cases such as hematoma has solid portion or multiple septum.

Successful, Full-Thickness Skin Graft in a Bald Eagle (Haliaeetus leucocephalus).

A subadult, male bald eagle (Haliaeetus leucocephalus) was evaluated after being found unable to fly, with large eschars on the dorsal head and right stifle. Because of the appearance and location, the lesions were believed to be caused by an electrical injury. Treatment included oral antibiotics, nonsteroidal anti-inflammatory drugs, pain medication, surgical debridement of the eschars, and trephining of the affected inner table of the cranium. A full-thickness skin graft was performed to expedite wound healing and minimize holding time. After 6 weeks, the bird had new feather growth on its dorsal head and was released. This is the first report, to our knowledge, of a nonmesh, full-thickness skin graft in an avian species. Full-thickness skin grafts should be considered as a surgical option in juvenile or adult avian patients with large dorsal head wounds.

How to Treat Chronic Subdural Hematoma? Past and Now.

Treatment of chronic subdural hematoma (CSDH) is relatively straightforward, however, there is still some debate regarding the best strategy for treatment. The most practical recommendations of up to date were identified by a review of literature. The author reviewed the literature on CSDH management from the past to now to identify the best methods. Till 1970s, craniotomy was the most commonly used method. Burr hole (BH) became the most preferred method from 1980s. In 1977, twist drill (TD) craniostomy was introduced. Closed system drainage after a BH or a TD became the most frequently used surgical method. Although nonsurgical treatment is often successful, trephination has more advantages, such as rapid resolution of the symptoms and short period of hospitalization. Nonsurgical treatment is possible in asymptomatic patients with a small CSDH. For the symptomatic patients with CSDH, trephination is the treatment of choice, either by BH or TD. In gray zone between surgery and medical treatment, shared decision making can be an ideal approach. For the recurrent CSDHs, repeated trephination is still effective for patients with a low risk of recurrence. If the risk of recurrence is high, additional management would be helpful. For the refractory CSDHs, it is necessary to obliterate the subdural space.

Burr Hole Drainage versus Small Craniotomy of Chronic Subdural Hematomas / 대한신경손상학회지

OBJECTIVE: Chronic subdural hematoma drainage is one of the most common procedures performed in neurosurgical practice. Not only burr hole drainage but also small craniotomy (diameter 3–5 cm) is frequently used neurosurgical treatment of chronic subdural hematomas. We assessed to compare the postoperative recurrence rates between burr hole drainage versus small craniotomy with closed-system drainage for chronic subdural hematomas. METHODS: From January 2016 to December 2018, 75 patients who were treated with burr hole drainage and small craniotomy with closed system drainage for the symptomatic chronic subdural hematoma were enrolled. Pre and postoperative computed tomography (CT) were used for radiologic evaluation. The choice of procedure was decided by preoperative CT images. RESULTS: 60 patients out of 75 patients underwent burr hole drainage, whereas 15 patients underwent small craniotomy. The overall postoperative recurrence rate was 16%. The recurrence occurred in 8 patients out of 60 patients in burr hole drainage group (13.3%) and 7 patients out of 15 patients in small craniotomy group (46.7%). The number of days of hospitalization was 10.3 days in burr hole drainage group and 15.7 days in small craniotomy group. CONCLUSION: Burr hole drainage would be sufficient to evacuate chronic subdural hematoma with lower recurrence rate, but small craniotomy was also needed in some cases such as hematoma has solid portion or multiple septum.

How to Treat Chronic Subdural Hematoma? Past and Now

Treatment of chronic subdural hematoma (CSDH) is relatively straightforward, however, there is still some debate regarding the best strategy for treatment. The most practical recommendations of up to date were identified by a review of literature. The author reviewed the literature on CSDH management from the past to now to identify the best methods. Till 1970s, craniotomy was the most commonly used method. Burr hole (BH) became the most preferred method from 1980s. In 1977, twist drill (TD) craniostomy was introduced. Closed system drainage after a BH or a TD became the most frequently used surgical method. Although nonsurgical treatment is often successful, trephination has more advantages, such as rapid resolution of the symptoms and short period of hospitalization. Nonsurgical treatment is possible in asymptomatic patients with a small CSDH. For the symptomatic patients with CSDH, trephination is the treatment of choice, either by BH or TD. In gray zone between surgery and medical treatment, shared decision making can be an ideal approach. For the recurrent CSDHs, repeated trephination is still effective for patients with a low risk of recurrence. If the risk of recurrence is high, additional management would be helpful. For the refractory CSDHs, it is necessary to obliterate the subdural space.

How to Treat Chronic Subdural Hematoma? Past and Now

Treatment of chronic subdural hematoma (CSDH) is relatively straightforward, however, there is still some debate regarding the best strategy for treatment. The most practical recommendations of up to date were identified by a review of literature. The author reviewed the literature on CSDH management from the past to now to identify the best methods. Till 1970s, craniotomy was the most commonly used method. Burr hole (BH) became the most preferred method from 1980s. In 1977, twist drill (TD) craniostomy was introduced. Closed system drainage after a BH or a TD became the most frequently used surgical method. Although nonsurgical treatment is often successful, trephination has more advantages, such as rapid resolution of the symptoms and short period of hospitalization. Nonsurgical treatment is possible in asymptomatic patients with a small CSDH. For the symptomatic patients with CSDH, trephination is the treatment of choice, either by BH or TD. In gray zone between surgery and medical treatment, shared decision making can be an ideal approach. For the recurrent CSDHs, repeated trephination is still effective for patients with a low risk of recurrence. If the risk of recurrence is high, additional management would be helpful. For the refractory CSDHs, it is necessary to obliterate the subdural space.

Complications Following Burr Hole Craniostomy and Closed-System Drainage for Subdural Lesions.

OBJECTIVE: Burr hole craniostomy and closed-system drainage (BCD) is a common surgical procedure in the field of neurosurgery. However, complications following BCD have seldom been reported. The purpose of this study was to report our experiences regarding complications following BCD for subdural lesions. METHODS: A retrospective study of all consecutive patients who underwent BCD for presumed subdural lesions at one institute since the opening of the hospital was performed. RESULTS: Of the 395 patients who underwent BCD for presumed subdural lesions, 117 experienced surgical or nonsurgical complications. Acute intracranial hemorrhagic complications developed in 14 patients (3.5%). Among these, 1 patient died and 5 patients had major morbidities. Malposition of the drainage catheter in the brain parenchyma occurred in 4 patients, and opposite-side surgery occurred in 2 patients. Newly developed seizures after BCD occurred in 8 patients (2.0%), five of whom developed the seizures in relation to new brain lesions. Eighty-eight patients (22.3%) suffered from nonsurgical complications after BCD. Pulmonary problems (7.3%) were the most common nonsurgical complications, followed by urinary problems (5.8%), psychologic problems (4.3%), and cognitive impairments (3.8%). CONCLUSION: The incidence of complications after BCD for subdural lesions is higher than previously believed. In particular, catastrophic complications such as acute intracranial hematomas and surgical or management errors occur at rates that cannot be ignored, possibly causing medico-legal problems. Great caution must be taken during surgery and the postoperative period, and these complications should be listed on the informed consent form before surgery.

Feasibility of Multiple Burr Hole With Erythropoietin in Acute Moyamoya Patients.

BACKGROUND AND PURPOSE: In patients with acute symptomatic moyamoya (<2 weeks), the feasibility of a combination therapy of multiple burr hole procedure under local anesthesia and intravenous erythropoietin pretreatment was assessed. We also identified the factors associated with transdural revascularization. METHODS: In this prospective single-arm study, perfusion-impaired patients presenting with transient ischemic attack or acute cerebral infarction were assessed. Combination therapy was performed to patients lacking transdural collaterals. Primary outcomes were evaluated clinically with modified Rankin Scale scores and radiologically with revascularization success (transhemispheric, trans-burr hole, and sufficient revascularizations [filling ≥33% of ipsilateral supratentorium]) at 6 months. Treatment-related adverse events were analyzed in 3 phases: pre burr hole, post burr hole, and after-discharge as secondary outcome. Factors associated with sufficient revascularization were investigated. RESULTS: Fifty hemispheres from 37 patients were included. Compared with discharge, modified Rankin Scale score at 6 months significantly improved (2.0 [0.0-5.0] versus 1.0 [0.0-4.0]; P<0.001). Majority had successful revascularization: trans-burr hole arteriogenesis (89.5%), transhemispheric arteriogenesis (98.0%), and sufficient revascularization (52.0%). There was no significant pre burr hole or post burr hole complication. Two (5.4%) transient ischemic attack and 1 (2.7%) cerebral infarction occurred after discharge. Presentation with acute infarction (odds ratio, 4.8; 95% confidence interval, 1.1-21.4), ipsilateral basal moyamoya vessels (odds ratio, 13.9; 95% confidence interval, 1.3-144.2), and delayed mean transit time (odds ratio, 3.9; 95% confidence interval, 1.3-12.2) predicted sufficient revascularization. CONCLUSIONS: Combination therapy allows safe and effective revascularization in moyamoya patients with acute ischemic presentation. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT03162588.

Complications Following Burr Hole Craniostomy and Closed-System Drainage for Subdural Lesions / 대한신경손상학회지

OBJECTIVE: Burr hole craniostomy and closed-system drainage (BCD) is a common surgical procedure in the field of neurosurgery. However, complications following BCD have seldom been reported. The purpose of this study was to report our experiences regarding complications following BCD for subdural lesions. METHODS: A retrospective study of all consecutive patients who underwent BCD for presumed subdural lesions at one institute since the opening of the hospital was performed. RESULTS: Of the 395 patients who underwent BCD for presumed subdural lesions, 117 experienced surgical or nonsurgical complications. Acute intracranial hemorrhagic complications developed in 14 patients (3.5%). Among these, 1 patient died and 5 patients had major morbidities. Malposition of the drainage catheter in the brain parenchyma occurred in 4 patients, and opposite-side surgery occurred in 2 patients. Newly developed seizures after BCD occurred in 8 patients (2.0%), five of whom developed the seizures in relation to new brain lesions. Eighty-eight patients (22.3%) suffered from nonsurgical complications after BCD. Pulmonary problems (7.3%) were the most common nonsurgical complications, followed by urinary problems (5.8%), psychologic problems (4.3%), and cognitive impairments (3.8%). CONCLUSION: The incidence of complications after BCD for subdural lesions is higher than previously believed. In particular, catastrophic complications such as acute intracranial hematomas and surgical or management errors occur at rates that cannot be ignored, possibly causing medico-legal problems. Great caution must be taken during surgery and the postoperative period, and these complications should be listed on the informed consent form before surgery.

The number of burr holes and use of a drain do not interfere with surgical results of chronic subdural hematomas / Tratamento cirúrgico do hematoma subdural crônico: o número de trepanações e o uso de dreno subdural não interferem no resultado cirúrgico

ABSTRACT Burr hole evacuation has been the most frequently-used procedure for the treatment of chronic subdural hematomas (CSDH). Objective: To evaluate whether the use of a drain and/or the number of burr holes for treatment of CSDH modifies the rates of recurrence and complications. Methods: A retrospective review of 142 patients operated on because of CSDH, between 2006 and 2015, analyzing recurrence and complications of the use of one or two burr holes with or without the use of a drain. Results: Thirty-seven patients had bilateral CSDH (26%) and 105 (73.9%) patients had unilateral CSDH. Twenty-two (59.4%) patients were given a drain and 15 (40.6%) were not. A total number of recurrences occurred in 22 (15.5%) patients and the total number of complications was in six (4.2%) patients. Mean follow-up time was 7.67 months. Conclusions: The number of burr holes and the use of the drain did not alter the rates of recurrence and complications in the treatment of CSDH.

RESUMO A trepanação é o procedimento mais utilizado para o tratamento de hematomas subdurais crônicos (HSDC). Objetivo: Avaliar o uso de dreno subdural e / ou o número de trepanações para tratamento de HSDC modifica as taxas de recidiva e complicações. Métodos: Uma revisão retrospectiva de 142 pacientes operados por HSDC entre 2006 e 2015 analisando recidiva e complicações usando um ou dois orifícios com ou sem uso de dreno. Resultados: Trinta e sete casos apresentaram HSDC bilaterais (26%) e 105 (73,9%) unilaterais. Em vinte e dois (59,4%) casos houve uso de dreno e em 15 (40,6%) não houve. O número total de recidivas foi de 22 casos (15,5%) e o número total de complicações foi de 6 casos (4,2%). O tempo médio de seguimento foi de 7,67 meses. Conclusões: O número de trepanações e o uso do dreno não alteraram as taxas de recidiva e complicações no tratamento de HSDC.

Evolving story: trepanation and self-trepanation to enhance brain function / Uma história em andamento: trepanação e auto-trepanação para aumentar a função cerebral

ABSTRACT Trepanation has been performed by people interested in enhancing mental power and well-being since the early 1960s. The pioneers and main proponents of the procedure are described here. The phenomenon appeared in Europe after a Dutch former medical student published a psychoactive drug-friendly scroll suggesting trepanation as a form of permanently increasing cerebral blood volume and function. He trepanned himself in 1965. Three of his friends became enthusiasts. They also submitted themselves to the procedure and published films and books describing their experiences. Two of them coauthored papers, in collaboration with Russian researchers, and created institutions to promote discussion on trepanation. One of these institutions organized trips to Central and South America to get the operation done. Dozens of people nowadays look for trepanation as a method of spiritualization and increasing well-being and mental power. The phenomenon has an uncertain future, however, as the main proponents and supporters are aging.

RESUMO Trepanação vem sendo feita por pessoas em busca de aumento da capacidade mental e bem estar desde a década de 1960. Os pioneiros e maiores proponentes do procedimento são aqui descritos. O fenômeno surgiu na Europa estimulado pela publicação de um manuscrito psicodélico e pela auto-trepanação feita por um ex-aluno de Medicina holandês, já falecido. Três amigos se tornaram entusiastas e também se submeteram a trepanação, apresentando o procedimento e descrevendo seus efeitos em livros ou filmes de certa repercussão. Dois deles criaram organizações de difusão e discussão sobre o tema, e uma destas instituições agencia e organiza viagens a países da América Central e do Sul para interessados. Trepanação foi feita até aqui com estes propósitos em dúzias de pessoas. O fenômeno tem, porém, futuro incerto, dado o envelhecimento de seus principais entusiastas.