Joshua Lucas

Conservative management of ossification of the posterior longitudinal ligament. A review

OBJECT Ossification of the posterior longitudinal ligament (OPLL) can result in significant myelopathy. Surgical treatment for OPLL has been extensively documented in the literature, but less data exist on conservative management of this condition. METHODS The authors conducted a systematic review to identify all reported cases of OPLL that were conservatively managed without surgery. RESULTS The review yielded 11 published studies reporting on a total of 480 patients (range per study 1-359 patients) over a mean follow-up period of 14.6 years (range 0.4-26 years). Of these 480 patients, 348 (72.5%) were without myelopathy on initial presentation, whereas 76 patients (15.8%) had signs of myelopathy; in 56 cases (15.8%), the presence of myelopathy was not specified. The mean aggregate Japanese Orthopaedic Association score on presentation for 111 patients was 15.3. Data available for 330 patients who initially presented without myelopathy showed progression to myelopathy in 55 (16.7%), whereas the other 275 (83.3%) remained progression free. In the 76 patients presenting with myelopathy, 37 (48.7%) showed clinical progression, whereas 39 (51.5%) remained clinically unchanged or improved. CONCLUSIONS Patients who present without myelopathy have a high chance of remaining progression free. Those who already have signs of myelopathy at presentation may benefit from surgery due to a higher rate of progression over continued follow-up.

Imaging of the Pituitary and Parasellar Region

The sellar and parasellar region is anatomically complex and encompasses many important vascular, endocrine, and neural structures. Pathology that arises within this region is often similarly complex, and requires a combination of endocrinologic, ophthalmologic, and neurologic examinations combined with advanced neuroimaging modalities. Magnetic resonance imaging (MRI) has become the gold standard for characterization of sellar and parasellar pathology due to the high contrast and detail it provides. Computed tomography (CT) allows for identification of bony involvement of lesions and also the general bony anatomy of the sellar region. Both modalities combined allow for complete characterization of sellar and parasellar pathology.

Ectopic ACTH-secreting pituitary adenoma of the sphenoid sinus: case report of endoscopic endonasal resection and systematic review of the literature.

Ectopic pituitary adenomas are exceedingly rare entities that are often misdiagnosed. The resulting delay in diagnosis may be particularly concerning in the case of Cushing syndrome caused by an ectopic adrenocorticotropic hormone (ACTH)-secreting pituitary adenoma. Although the total resection of ectopic adenomas results in rapid and durable remission, persistent Cushing syndrome is often associated with permanently damaging invasive procedures and significantly higher risk of mortality. The authors report the case of a 48-year-old man with ACTH-dependent Cushing syndrome. On the morning before surgery, his serum cortisol measured 51 μg/dl, his ACTH level was 195.7 pg/ml, and his urinary free cortisol level was 2109 μg/day. Serum cortisol was not suppressed with the administration of high-dose dexamethasone. Imaging showed separate masses in both the sphenoid sinus and the pituitary gland, complicating the diagnostic process and requiring pathological assessment of both masses. No other abnormalities were found on thoracic, abdominal, or pelvic scans. Gross-total resection of both lesions was accomplished via an endoscopic endonasal transsphenoidal approach. Pathology confirmed an ectopic ACTH pituitary adenoma of the sphenoid sinus and a Crooke hyaline change of the pituitary gland. The patient achieved stable hormonal remission without significant postoperative complications, returned to full activity within 3 months, and remained disease free nearly 1 year after tumor resection. In a systematic literature review, the authors identified 41 cases of ectopic ACTH-secreting pituitary adenomas, including 18 arising in the sphenoid sinus without direct involvement of the sella. Including the case described here, the total number of ectopic ACTH pituitary adenomas arising in the sphenoid sinus was 19, and the total number of ectopic ACTH pituitary adenomas without regard to location was 42. For the 19 patients with adenomas found in the sphenoid sinus, ages ranged from 16 to 76 years, and there were 15 women and 4 men. The mean and median diameters of the resected sphenoid masses were 13.9 and 8 mm, respectively, with a range of 3-55 mm. Seven were microadenomas (< 1 cm). Fifteen of the 19 cases reported serum ACTH and morning cortisol levels, the means of which were 106.7 pg/ml and 32.5 μg/dl, respectively. Gross-total tumor resection was achieved in all patients except one, and in all of them durable hormonal remission of Cushing syndrome was achieved (mean follow-up time 20 months). Ectopic pituitary adenomas are rare but important causes of Cushing syndrome and related endocrinopathies, particularly because of the rapid onset and severity of symptoms with atypical presentation. Ectopic pituitary adenomas, especially those in the nasal cavity, nasopharynx, or paranasal sinuses, are easily misidentified. Any patient presenting with signs and symptoms of Cushing syndrome without any obvious pituitary adenoma or other sources of hypercortisolemia should be thoroughly screened for an ectopic adenoma. However, as with the case presented here, the coincident existence of a sellar mass should not preclude the possibility of an ectopic source. There should be a high degree of clinical suspicion for any mass in the general area surrounding the sella when evaluating Cushing syndrome.

Congress of Neurological Surgeons Systematic Review and Evidence-Based Guideline on Primary Management of Patients With Nonfunctioning Pituitary Adenomas.

BACKGROUND Nonfunctioning pituitary adenomas (NFPAs) are among the most common pituitary lesions and may present clinically with vision loss and hypopituitarism. OBJECTIVE To characterize the existing literature as it pertains to the initial management of NFPAs. METHODS A systematic literature review was conducted to identify and screen articles assessing primary treatment options (surgical, medical, radiation based, or observation) for NFPAs. Outcomes assessed included vision-, endocrine-, and headache-related symptoms, as well as tumor response to therapy. Twenty-five studies met inclusion criteria for analysis. RESULTS A considerable amount of class II evidence (14 studies) was identified supporting primary surgical intervention in patients with symptomatic NFPA macroadenomas, resulting in immediate tumor volume reduction in nearly all patients and a residual tumor rate of 10% to 36%. One prospective, observational cohort study and multiple retrospective studies showed improved visual function in 75% to 91% of surgically treated patients and improved hypopituitarism in 35% to 50% of patients. Limited class II evidence showed inconsistent benefits for observation alone (1 study), primary radiation-based treatment (3 studies), or primary medical treatment (8 studies) for improving vision, headaches, hypopituitarism, or tumor volume. One retrospective study implementing observation alone showed tumor progression in 50% of patients and a requirement for surgery in 21% of patients. Eight studies assessing primary medical therapy for NFPAs showed inconsistent tumor response rates using somatostatin analogs (12%-40% response rate), dopamine agonist therapy (0%-61% response rate), or combination therapy (60% response rate). Three studies reporting primary radiosurgery for NFPAs showed decreased tumor size in 38% to 60% of patients. CONCLUSION Multiple retrospective and some prospective studies have demonstrated consistent effectiveness of primary surgical resection of symptomatic NFPAs with acceptable morbidity rates. Limited and inconsistent reports are available for alternative treatment strategies, including radiation, medical treatment, and observation alone; these modalities may, however, play a valid role in patients who are not surgical candidates. Based on the available evidence, the authors recommend surgical resection as the preferred primary intervention for symptomatic NFPAs. The full guidelines document for this chapter can be located at https://www.cns.org/guidelines/guidelines-management-patients-non-functioning-pituitary-adenomas/Chapter_5. ABBREVIATION NFPA, nonfunctioning pituitary adenoma.

Congress of Neurological Surgeons Systematic Review and Evidence-Based Guidelines on the Management of Patients With Nonfunctioning Pituitary Adenomas: Executive Summary.

BACKGROUND Nonfunctioning pituitary adenomas (NFPAs) are the most frequent pituitary tumors. OBJECTIVE To create evidence-based guidelines for the initial management of NFPAs. METHODS A multidisciplinary task force composed of physician volunteers and evidence-based medicine-trained methodologists conducted a systematic review of the literature relevant to the management of NFPAs. To ascertain the class of evidence for the posttreatment follow-ups, the task force used the Clinical Assessment evidence-based classification. RESULTS Seven topics of importance were chosen for detailed evaluation. The topics addressed include preoperative evaluation, primary treatment, treatment options for residual tumors after surgery, and postoperative patient management. For preoperative patient evaluation, the guideline task force focused on preoperative imaging, preoperative laboratory evaluation, and preoperative ophthalmologic evaluation. For primary treatment, this guideline addresses surgical resection, medical therapy, radiation therapy, the natural history of untreated tumors, surgical methodologies, such as endoscopy, microscopy, or craniotomy, and intraoperative adjuncts like neuronavigation, cerebrospinal fluid diversion, or intraoperative imaging. For residual tumor treatment, the guideline task force evaluated radiation vs observation. Additional topics addressed in this guideline regarding postoperative patient management include the frequency of postoperative imaging, postoperative endocrine evaluation, and postoperative ophthalmologic evaluation. CONCLUSION Although there is clearly a need for more randomized trials generating higher levels of evidence to help guide physicians managing NFPAs, the existing evidence provided valuable data upon which the guidelines described in the 7 articles generated from this effort are based. The full guidelines document can be located at https://www.cns.org/guidelines/guidelines-management-patients-non-functioning-pituitary-adenomas. ABBREVIATION NFPA, nonfunctioning pituitary adenoma.

Cervical spine dural arteriovenous fistula with coexisting spinal radiculopial artery aneurysm presenting as subarachnoid hemorrhage: case report.

BACKGROUND AND IMPORTANCE We present a patient with a cervical spine dural arteriovenous fistula associated with a radiculopial artery aneurysm at the same vertebral level presenting with subarachnoid hemorrhage. CLINICAL PRESENTATION A 45-year-old Native American man presented with sudden-onset severe headache, lethargy, and right hemiparesis. Computed tomography (CT) of the head showed subarachnoid hemorrhage and hydrocephalus. A subsequent CT of the neck showed an anterior spinal subdural hematoma from C2 to C4 causing mild cord compression. Carotid and vertebral angiography failed to demonstrate an intracranial aneurysm, but showed a spinal dural arteriovenous fistula originating from the right vertebral artery at the C5 neuroforamen. The severity of the patients symptoms, atypical for rupture of a dural arteriovenous fistula, prompted more thorough angiographic evaluation. Thus, injection of the right thyrocervical trunk was performed, demonstrating a 4-mm spinal radiculopial artery aneurysm. Following ventriculostomy, a hemilaminectomy from C4 to C7 was performed with disconnection of the fistula from its drainage system. Subsequent resection of the aneurysm, which was determined to be the cause of the hemorrhage, was accomplished. The patient improved neurologically and was discharged to rehabilitation. CONCLUSION Spinal cord aneurysms from a separate vascular distribution may coexist with spinal dural arteriovenous fistulas. In the setting of spinal hemorrhage, especially in situations with an atypical clinical presentation, comprehensive imaging is indicated to rule out such lesions.

Endoscopic surgery for pituitary tumors.

The endoscopic transsphenoidal approach to the sella turcica has been developed and refined for the treatment of pituitary lesions. Studies comparing endoscopic transsphenoidal surgery with the traditional microscopic transsphenoidal technique have found equivalent or improved rates of tumor resection and hormonal remission, and equal or lower rates of complications. This procedure affords improved panoramic visualization, illumination, surgical freedom, and mobility. This approach facilitates two-handed microdissection and the ability to look around corners using angled lenses, promoting maximal tumor resection and preservation of the pituitary gland. Experience, technologic advancements, and improved instrumentation are likely to contribute to improved surgical outcomes.

Effects of Ionizing Radiation on Cerebral Vasculature

ith the emergence and proliferation of radiation therapy in the treatment paradigm for intracerebral W lesions, much research has been conducted to identify the negative consequences of treatment and their causes. It was discovered early in the course of this work that late radiation-induced myelopathic changes in the central nervous system could be attributed to 2 separate entities: direct injury to susceptible glial cells and damage to the vascular system supplying them (2, 3). More recent attempts at characterizing the specific effects of radiation exposure to the cerebral vasculature have identified several alterations in the cellular composition and structure of the vessel themselves, as well as changes in the hemodynamics of the vasculature following radiation damage.

Endoscopic Endonasal and Keyhole Surgery for the Management of Skull Base Meningiomas

The resection of anterior skull base meningiomas has traditionally been performed via pterional or unilateral/bilateral subfrontal craniotomies. The supraorbital keyhole approach and the endoscopic endonasal approach, techniques in which the endoscope is used to aid visualization, were developed to provide alternative, less-invasive approaches to aid the resection of these tumors. The individual characteristics of each tumor, such as location and size, are the main determinants guiding the choice of approach. In this article, the advantages and disadvantages of each approach are discussed, along with complications specific to each technique. Furthermore, a detailed procedural description of each surgical approach is described.

Space Available for Cord, Motion, and disc degeneration at the adjacent segments level of degenerative cervical spondylolisthesis using kinematic MRI

The objective was to evaluate motion, disc degeneration and Space Available for Cord (SAC) at the adjacent segments of degenerative cervical spondylolisthesis (DCS) using kinematic Magnetic Resonance Imaging (kMRI). The cervical spine kMRI of sixty-one DCS spinal levels (38 anterolisthesis and 23 retrolisthesis) were analyzed at the listhesis level and its adjacent segments in three position using kMRI. MRAnalyzer3 was used to analyze translation, angular motion and SAC. The caudad level had significantly less translation motion than the listhesis level in overall DCS or grade 2 anterolisthesis group (P<0.05). The cephalad level had significant more translational motion than the caudad level in overall DCS or grade 1 retrolisthesis group (P<0.05). For disc degeneration, the cephalad level had the least disc degeneration and showed significant difference with the listhesis level in overall DCS or overall anterolisthesis or overall retrolisthesis or grade 2 anterolisthesis or grade 1 or 2 retrolisthesis (P<0.05). For SAC, the listhesis level had the narrowest space in overall DCS groups. In neutral position, grade 1 anterolisthesis had significantly larger SAC at the listhesis and the cephalad level than grade 1 retrolisthesis (P<0.05). In conclusion, DCS affected cervical spine motion and kinematics. Grade 1 retrolisthesis showed tendency of narrower SAC at the cephalad level more than the same grade anterolisthesis. The likelihood of the adjacent segment disease and spinal cord compression are higher in both grade 2 anterolisthesis and retrolisthesis.