Novel imaging techniques using 18 F-florbetapir PET/MRI can guide fascicular nerve biopsy in amyloid multiple mononeuropathy.

BACKGROUND: Multiple mononeuropathy is a rare presentation of primary (AL) amyloidosis and nerve biopsy is usually needed for diagnosis. Conventional imaging is useful to identify proximal nerve involvement but may be inadequate. We report a patient with multiple mononeuropathy whose presentation was suggestive of AL amyloid neuropathy and in whom repeated tissue biopsies were negative for amyloid (including two sensory nerves and one muscle). METHODS: The patient underwent magnetic resonance imaging (MRI) and whole body 18 F-florbetapir positron emission tomography (PET)/MRI. RESULTS: Whole body 18 F-florbetapir PET/MRI revealed abnormal low-level florbetapir uptake in the right proximal tibial and peroneal nerves, which provided a target for a sciatic bifurcation fascicular nerve biopsy that was diagnostic of AL amyloidosis. CONCLUSIONS: 18 F-florbetapir PET/MRI imaging is a promising diagnostic tool for patients with suspected peripheral nerve amyloidosis (including multiple mononeuropathy) in whom conventional imaging and nerve and muscle biopsies miss the pathology.

Percutaneous image-guided biopsy in malignant peripheral nerve sheath tumors.

BACKGROUND: The decision to biopsy a peripheral nerve tumor is largely based on its presumed behavior and prognosis, determined by patient history, clinical exam, and radiologic characteristics. Percutaneous image-guided biopsy is not without risk in patients with malignant peripheral nerve sheath tumors (MPNSTs); in particular, there may be concern regarding worsening neurologic function, increasing neuropathic pain, and incorrect or absent diagnosis. METHODS: Following approval by our institutional review board, we reviewed records from 1990 to 2019 at our institution's three main sites ("our institution"). Patients with pathology-proven MPNST were selected. Further inclusion criteria included image-guided percutaneous biopsy performed at our institution, pathology report available for review, and follow-up documentation to determine post-biopsy complications. RESULTS: Three hundred thirty-one patients with MPNST were reviewed. In total, 73 patients undergoing image-guided percutaneous biopsies were included. Twenty-two (30.1%) had biopsy-related complications. This included ten patients with misdiagnosis (13.7%) and six patients with non-diagnostic biopsies (8.2%). Six patients had new or worsened pain that resolved with time and neuropathic pain medication (8.2%), and one patient had subjectively worsened proximal weakness (1.3%) which resolved. CONCLUSION: We found nearly a third of patients undergoing biopsy had a biopsy-related complication. The single largest complication was the inability to obtain an accurate diagnosis (21.9%) with the first biopsy. This may lead to the need for repeat percutaneous or open biopsies, or a non-oncologic initial surgery with implications for disease-free and overall survival. Neurologic complications including exacerbation of pain or a deficit were rare and transient. It remains important that clinicians balance the potential risks and benefits based on individual patient characteristics when determining the necessity of an image-guided percutaneous biopsy.

Preoperative SRS pain score is the primary predictor of postoperative pain after surgery for adolescent idiopathic scoliosis: an observational retrospective study of pain outcomes from a registry of 1744 patients with a mean follow-up of 3.4 years.

BACKGROUND: Traditionally, adolescent idiopathic scoliosis (AIS) has not been associated with back pain, but the increasing literature has linked varying factors between pain and AIS and suggested that it is likely underreported. PURPOSE: Our objective was to investigate factors associated with post-op pain in AIS. METHODS: A prospectively collected multicenter registry was retrospectively queried. Pediatric patients with AIS having undergone a fusion with at least 2 years of follow-up were divided into two groups: (1) patients with a postoperative SRS pain score ≤ 3 or patients having a reported complication specifically of pain, and (2) patients with no pain. Patients with other complications associated with pain were excluded. RESULTS: Of 1744 patients, 215 (12%) experienced back pain after postoperative recovery. A total of 1529 patients (88%) had no complaints of pain, and 171 patients (10%) had pain as a complication, with 44 (2%) having an SRS pain score ≤ 3. The mean time from date of surgery to the first complaint of back pain was 25.6 ± 21.6 months. In multivariate analysis, curve type (16% of Lenke 1 and 2 curves vs. 10% of Lenke 5 and 6, p = 0.002) and a low preoperative SRS pain score (no pain 4.15 ± 0.67 vs. pain 3.75 ± 0.79, p < 0.001) were significant. When comparing T2-4 as the upper instrumented vertebrae in a subgroup of Lenke 1 and 2 curves, 9% of patients had pain when fused to T2, 13% when fused to T3, and 18% when fused to T4 (p = 0.002). CONCLUSION: 12% of all AIS patients who underwent fusion had back pain after postoperative recovery. The most consistent predictive factor of increased postoperative pain across all curve types was a low preoperative SRS pain score. These slides can be retrieved under Electronic Supplementary Material.

Image-guided percutaneous biopsy of peripheral nerve tumors of indeterminate nature: risks and benefits.

BACKGROUND: Usual management of peripheral nerve tumors is to avoid biopsy in those that are likely benign; the risk of biopsy outweighs the benefit of definitive tissue diagnosis. Biopsy of presumed malignant lesions is performed widely. There is a subset of peripheral nerve tumors that are not easily categorized as benign or malignant based on the clinical and/or radiological features alone. The role of biopsy in peripheral nerve tumors of uncertain character remains controversial and the risk of biopsy (and the potential risk/benefit ratio) for these lesions is not known. METHODS: Following approval by our institutional review board, we reviewed all notes of a single peripheral nerve surgeon from 2000 to 2018 with respect to image-guided percutaneous biopsy of nerve tumors. We divided these patients into 3 groups based on clinicoradiologic features. We determined the risk of complications and the "hit rate" for patients with peripheral nerve tumors of uncertain behavior, defined as the percentage of patients sent for percutaneous biopsy who had a malignancy on their final pathology. RESULTS: Of 82 patients with tumors of uncertain behavior, 9 had complications, and 23 had malignant final pathology (a "hit rate" of 27.7%). Neurosurgical referral for biopsy of tumors of uncertain behavior was made in 60 patients. Twenty-two had malignant final pathology ("hit rate"= 36.7%). Non-neurosurgical referral for biopsy was made in 22 patients with tumors of uncertain behavior. Two had malignant final pathology ("hit rate"= 4.55%). There was a statistically significant difference between the "hit rate" for the two groups (p = 0.021). CONCLUSIONS: The decision to biopsy a peripheral nerve tumor is largely based on the presumed behavior and prognosis, determined via clinicoradiologic characteristics. Patient care might be improved by delaying percutaneous biopsy of peripheral nerve lesions until after a neurosurgical evaluation.

Association of intraneural perineurioma with neurofibromatosis type 2.

BACKGROUND: Neurofibromatosis type 2 (NF2) is a genetic disorder characterized by mutations of the NF2 tumor suppressor gene that predisposes patients to develop multiple tumors in the peripheral and central nervous system. The most common neoplasms associated with the disease are schwannomas and meningiomas. Both have been shown to contain abnormalities in chromosome 22 and the NF2 gene, suggesting a genetic component to their pathogenesis. Perineuriomas are rare benign tumors arising from the perineural cells. They are commonly classified as intraneural and soft tissue perineuriomas. Several studies have reported mutations in genes on chromosome 22 in both types of perineuriomas, and there are reports of soft tissue perineuriomas associated with NF2 gene mutations. Despite this, perineuriomas are not considered as part of the NF2 constellation of tumors. METHOD: The electronic medical records were searched for patients with a radiologic or pathologic diagnosis of intraneural perineurioma. Patients with clinical signs and genetic testing consistent with a diagnosis of NF2 were further evaluated. RESULTS: Of 112 patients meeting inclusion criteria, there were two cases of intraneural perineurioma in patients with NF2 treated at our institution (1.8%). We include a third patient treated at another facility for whom we performed a virtual consultation. CONCLUSIONS: The rarity of both NF2 and perineuriomas could explain the rarity of perineuriomas in the setting of NF2. Furthermore, there is divergent intraneural and soft tissue perineurioma somatic mutation pathogenesis, and there may be cytogenetic overlap between perineuriomas and multiple tumor syndromes. Our observed occurrence of intraneural perineurioma in the setting of NF2 in several patients provides further evidence of a potential link between the NF2 gene and the development of intraneural perineurioma.

Effects of Cleft Width and Veau Type on Incidence of Palatal Fistula and Velopharyngeal Insufficiency After Cleft Palate Repair.

BACKGROUND: Postoperative fistulae and velopharyngeal insufficiency (VPI) are 2 important complications after cleft palate repair. The effects of preoperative cleft width on outcomes after cleft palate repair have been rarely studied. METHODS: A retrospective review of all patients undergoing primary cleft palatoplasty by a single surgeon between 2004 and 2011 was performed. Primary outcomes were palatal fistula and VPI, defined as the need for corrective surgery after failing conservative speech-language therapy. Logistic regression analysis was performed to identify factors associated with the primary outcomes. RESULTS: One hundred seventy-seven patients (84 men and 93 women) were identified. Median age at repair was 10 months with median follow-up of 3.80 years. Preoperative cleft width was 10 mm or less for 72 (41%) patients, 11 to 14 mm for 54 (30%) patients, and 15 mm or greater for 51 (29%) patients. Palatal fistula was observed in 8 (4.5%) patients, but required surgical repair in only 2 (1.1%). Fistula was overall associated with Veau IV classification (odds ratio, 8.13; P < 0.01) but not with cleft width. Velopharyngeal insufficiency needing surgical intervention occurred in 9 patients (7.38% of patients older than 4 years) and was associated with increasing cleft width (odds ratio, 1.29; P = 0.011). Outcomes were similar for patients undergoing surgery in the earlier and later halves of the study. CONCLUSIONS: This retrospective review is one of the first from the United States to explore the associations between measured cleft width and outcomes after palatoplasty. Overall rates of palatal fistula and VPI were low, corroborating previous studies showing good outcomes with the 2-flap palatoplasty. After adjusting for multiple variables including Veau type, cleft width was associated with higher VPI rates but not with fistula formation. Cleft width is a unique preoperative factor that should be considered and studied as a potential predictor of outcomes.

Velopharyngeal Insufficiency Rates After Delayed Cleft Palate Repair: Lessons Learned From Internationally Adopted Patients.

Most surgeons recommend cleft palate repair between 6 and 12 months of age. Internationally adopted patients often undergo delayed repair due to social circumstances. There are few outcomes studies on this population. We conducted a 13-year retrospective review of all patients undergoing primary cleft palate repair at a single tertiary-care academic medical center between 1993 and 2006. The primary outcome was velopharyngeal insufficiency, defined as the recommendation for corrective surgery after multiple formal speech assessments. Two hundred one patients (102 males and 99 females) were identified. One hundred eighty-three repairs were performed before 18 months of age (standard repair group). Eighteen repairs were performed after 18 months of age (delayed repair group), with international adoption being a circumstance in 16 cases. The delayed and standard repair groups were similar with regard to sex, presence of craniofacial syndrome, Veau class, cleft size and laterality, type of repair, and operating surgeon. Mean follow-up was 9.3 years, with minimum follow-up of 5.0 years. Six (33%) of 18 patients in the delayed repair group developed velopharyngeal insufficiency compared to 23 (13%) of 183 in the standard repair group (P = 0.03 by Fisher exact test). These data demonstrate that internationally adopted patients undergoing delayed palate repair suffer especially poor speech outcomes. Physiologic differences in patients undergoing late repair, as well as social factors including adaptation to a new language and culture, may be factors. Early repair should be performed when possible.

Harvey Cushing's Contributions to Plastic Surgery: Bilateral Cleft Lip Repair.

Harvey Cushing has been deemed by many as the neurosurgeon of the 20th century. Cushing's unknown contributions to the field of plastic and reconstructive surgery were only recently reported. Further review of his teaching and operative records, brought from Johns Hopkins to Yale University, revealed an unpublished case of bilateral cleft lip repair that he performed. In this article, we present in detail this comprehensive case and describe, with the help of his personal teaching notes and illustrations, how Cushing combined methods from world-renowned surgeons to approach bilateral cleft lip deformities.

Prevalence of carpal tunnel syndrome symptoms among neurosurgical spine surgeons.

Background: Neurosurgeons, particularly spine surgeons, have high exposure to vibrations via electric or pneumatic drills and repetitive motion. Although no data exist for the prevalence of carpal tunnel syndrome (CTS) among these surgeons, anecdotal evidence suggests the rate of symptoms is higher than in the general population. Methods: An anonymous questionnaire was developed to assess demographics, practice patterns, presence of CTS symptoms, and treatment (time off, bracing, medication, injections, surgery). The survey was sent via anonymous email link to members of the AANS/CNS Joint Section on Disorders of the Spine and Peripheral Nerve. Results: 101 members responded: 44 reported at least one symptom related to CTS (43.6%). There was no statistically significant relationship between overall or spine case volume, the number of cases performed annually/daily, and CTS symptoms. Respondents working in non-teaching settings were significantly more likely to have CTS symptoms than academic teaching institutions (50.0% v. 45.0%; p = 0.0112). Conclusions: Our survey demonstrated CTS to be more prevalent in spine neurosurgeons (43.6%) than in the general population (1-5%). The lack of significant association between most practice-based metrics and CTS symptoms may indicate that respondents have a minimum case volume that exceeds the amount of vibration exposure/repetitive motion to develop symptoms. The significantly increased prevalence of CTS among neurosurgeons at non-teaching institutions suggests that residents provide operative assistance offsetting the vibration exposure/repetitive motion by attendings. Further research may determine the root cause for the high prevalence of CTS in spine neurosurgeons and devise methods for reducing vibration exposure.

Thoracic Intervertebral Disc Herniation Associated With Chronic Anabolic Androgenic Steroid Use: A Case Report.

Anabolic androgenic steroids (AAS) are relatively cheap and accessible medications, commonly used by athletes and bodybuilders for performance enhancement and muscle growth stimulation. AAS usage has been associated with musculoskeletal injuries, such as tendon and ligament ruptures, and numerous other detrimental health effects. Despite these risks, individuals continue to self-administer these drugs in supraphysiologic doses. Here, we present a case of a male bodybuilder with chronic AAS use who developed a spinal thoracic intervertebral disc herniation requiring decompression and fusion. We use this case to highlight a severe potential risk associated with chronic AAS abuse and review the current literature on the biochemical, physical, and physiologic mechanisms linking chronic AAS use, weight-bearing exercise, and the risk of musculoskeletal injuries such as intervertebral disc herniations.

Survival after resection of malignant peripheral nerve sheath tumors: Introducing and validating a novel type-specific prognostic model.

Background: This study aimed to assess the performance of currently available risk calculators in a cohort of patients with malignant peripheral nerve sheath tumors (MPNST) and to create an MPNST-specific prognostic model including type-specific predictors for overall survival (OS). Methods: This is a retrospective multicenter cohort study of patients with MPNST from 11 secondary or tertiary centers in The Netherlands, Italy and the United States of America. All patients diagnosed with primary MPNST who underwent macroscopically complete surgical resection from 2000 to 2019 were included in this study. A multivariable Cox proportional hazard model for OS was estimated with prespecified predictors (age, grade, size, NF-1 status, triton status, depth, tumor location, and surgical margin). Model performance was assessed for the Sarculator and PERSARC calculators by examining discrimination (C-index) and calibration (calibration plots and observed-expected statistic; O/E-statistic). Internal-external cross-validation by different regions was performed to evaluate the generalizability of the model. Results: A total of 507 patients with primary MPNSTs were included from 11 centers in 7 regions. During follow-up (median 8.7 years), 211 patients died. The C-index was 0.60 (95% CI 0.53-0.67) for both Sarculator and PERSARC. The MPNST-specific model had a pooled C-index of 0.69 (95%CI 0.65-0.73) at validation, with adequate discrimination and calibration across regions. Conclusions: The MPNST-specific MONACO model can be used to predict 3-, 5-, and 10-year OS in patients with primary MPNST who underwent macroscopically complete surgical resection. Further validation may refine the model to inform patients and physicians on prognosis and support them in shared decision-making.

Early hypospadias repair: the contributions of Harvey Cushing.

PURPOSE: The early evolution of surgical reconstructive techniques has been well documented in the literature. However, a review of the Johns Hopkins hospital surgical files revealed an interesting participant in early hypospadias repair: Harvey Cushing (1869-1939). METHODS: Following IRB approval, we reviewed the surgical records from 1896 to 1912 and selected from among his non-neurosurgical patients, one case of first-stage hypospadias repair. RESULTS: Cushing operated upon the 21-year-old patient, performing a first-stage repair of hypospadias, in conjunction with a repair of a right inguinal hernia. The patient was discharged following a second stage operation. At that time, the patient was in good condition and was voiding appropriately. There was no further follow-up. CONCLUSION: The repair of hypospadias evolved through the work of European surgeons, from the mid-eighth century through the early nineteenth century. The case we report here illustrates Cushing's early work in the fields of urologic and plastic surgery.

Bilateral traumatic facial paralysis. Case report.

Although traumatic injury of the facial nerve is a relatively common condition in neurosurgical practice, bilateral lesions related to fracture of temporal bones are seldom seen. We report the case of a 38-year-old patient admitted to Intensive Care Unit after severe head trauma requiring ventilatory support (Glasgow Coma Scale of 7 on admission). A computed tomography (CT) scan confirmed a longitudinal fracture of the right temporal bone and a transversal fracture of the left. After successful weaning from respirator, bilateral facial paralysis was observed. The possible aetiologies for facial diplegia differ from those of unilateral injury. Due to the lack of facial asymmetry, it can be easily missed in critically ill patients, and both the high resolution CT scan and electromyographic studies can be helpful for correct diagnosis.

"Glandular intoxication" following emergent tracheotomy during transsphenoidal surgery for acromegaly: Cushing's 1910 unrecognized case of thyroid storm?

Harvey Cushing's monograph The Pituitary Body and Its Disorders describes Case XXXVIII, H. M. B., a 33 year-old man who presented with acromegaly in 1910. The detailed operative note reports an emergency tracheotomy performed following induction of anesthesia, and immediately prior to a naso-labial approach to a suspected sellar lesion. Cushing's post-operative notes document a significant increase in temperature prior to the patient's death. Cushing offered an explanation for the patient's symptoms immediately pre-mortem, which is largely unsatisfying. Following institutional review board approval, and through the courtesy of the Alan Mason Chesney Archives, the surgical records from the Johns Hopkins Hospital, 1896-1912, were reviewed. A review of the original surgical file revealed a more extensive description of the emergent tracheotomy required following induction of anesthesia, and provided additional information regarding the patient's symptoms in the immediate pre-mortem period. Namely, the urgent tracheotomy transected the thyroid gland, and post-operatively the patient experienced significant tachycardia and hyperthermia, consistent with thyroid storm. The new information regarding the hospital course of H. M. B. offers insight into the previously incompletely described circumstances surrounding his emergent tracheotomy, and subsequent death. Additionally, the case underscores the clinical importance of recognizing and appropriately treating thyroid storm.

ACTH-secreting pituitary adenomas: size does not correlate with hormonal activity.

ACTH-secreting pituitary adenomas (Cushing's disease, CD) are the most frequent cause of Cushing's syndrome. To test whether the size of ACTH-secreting adenomas correlates with the degree of biochemical and clinical features of hypercortisolism, we retrospectively reviewed all newly diagnosed CD patients seen at our institution by two neuro-endocrinologists over a 10-year time period. We documented the number of clinical manifestations and baseline hormonal measurements. There were 37 microadenomas (µAs) and 16 macroadenomas (MAs). We sought to characterize the relationship between tumor size (µA vs. MA) and number of signs and symptoms of hypercortisolism and biochemical assessment of hypercortisolemia. There were no significant differences in mean age, BMI, or prevalence of hypertension and type 2 diabetes between the µA and MA groups. However, the MAs had fewer clinical manifestations of hypercortisolism (29.4% vs. 36.1%, P = 0.02) compared to µAs. There was a higher prevalence of easy bruisability and proximal muscle weakness in the µAs, but otherwise the prevalence of signs and symptoms were similar between groups. The MAs had a lower random serum cortisol (18.2 ± 2.4 vs. 25.9 ± 1.8 mcg/dl, P = 0.018), lower cortisol:ACTH ratio (0.25 ± 0.03 vs. 0.42 ± 0.05, P < 0.048), and lower cortisol:tumor diameter ratio (14.1 ± 2.2 vs. 56.8 ± 7.2, P < 0.0001) than the µAs. We conclude that tumor size does not directly correlate with the extent of hormonal activity in ACTH-secreting adenomas. Biochemical activity and clinical manifestations may be mild even in larger tumors, and therefore a high index of suspicion may be necessary to recognize hypercortisolism in pituitary MAs.

Posthemorrhagic hydrocephalus in preterm neonates: socioeconomic characteristics in a single-institution experience.

UNLABELLED: Patients with posthemorrhagic hydrocephalus (PHH) from germinal matrix hemorrhage of prematurity often require numerous early interventions, as well as long-term follow-up care from pediatric neurosurgeons, which continues to place high demands on the existing workforce and pediatric health care system. There are established correlations between premature birth and low socioeconomic status. The aim of this study is to characterize the demographic profile and follow-up patterns in this subpopulation of surgically treated infants with PHH from prematurity. METHODS: A retrospective analysis of the electronic patient records for a single institution, from 2007 to 2010, was performed. All patients who underwent neurosurgical intervention for the treatment of PHH were selected for further analysis. Data elements available within the records included patient demographic features, inpatient treatments and procedures, inpatient mortality rates, length of stay, and postoperative follow-up at the institution. Socioeconomic status was assessed using the median household income for the patient's zip code, as reported in the United States Census for the year 2000. RESULTS: A total of 40 patients who underwent neurosurgical intervention for PHH at a single institution were identified. More patients were female (52.5%); the majority of patients were Black (57.5%). No patients were uninsured; most patients had public insurance (62.5%), and 65% were below the Maryland State median household income (USD 52,868). There were trends toward more frequent emergency room visits among those covered by public insurance and those below the state and national median house income, although differences were not statistically significant. CONCLUSIONS: Our data indicate that the majority of patients fall within lower household income brackets, are born into households earning less than the statewide median household income, and are covered by public insurance. In light of the socioeconomic profile of the patient population reported here, these data may prove to be useful in preventative strategies aimed toward prematurity, PHH, and the ongoing treatment of hydrocephalus by pediatric neurosurgeons and other pediatric subspecialists.

Human Exposure to Hand-Arm Vibration from a Surgical Drill During Simulated Spine Surgery.

OBJECTIVE: During spine surgery, surgeons are exposed to vibrations from surgical drills. Increased exposure to vibration can result in neurologic, vascular, and musculoskeletal impairments. To reduce these risks, occupational health standards have been implemented to limit exposure levels. The purpose of this study was to quantify human exposure to hand-arm vibration from a surgical drill during a simulation of a common spine procedure. METHODS: Vibration measurements were collected during three 30-second surgical trials on a fresh frozen cadaver torso specimen using a standard surgical drill. The daily vibration exposure A(8) was evaluated on the basis of International Organization for Standardization 5349-1, and the occupational health standards, exposure action value, and exposure limit value were calculated. RESULTS: On the basis of vibration exposure, surgeons in this study reached their exposure limits in 8 minutes to monitor tool usage and 32 minutes to terminate equipment usage. CONCLUSIONS: The results demonstrate that a common surgical drill transmits hand-arm vibration levels approaching the exposure action value and exposure limit value over short periods of use. Further investigation is needed to determine the total vibration exposure over an entire workday, specifically in surgeons who perform multiple surgeries within a single day.

Morbidity and Function Loss After Resection of Malignant Peripheral Nerve Sheath Tumors.

BACKGROUND: Malignant peripheral nerve sheath tumors (MPNSTs) are aggressive soft tissue sarcomas. Their resection may lead to serious morbidity. Incidence of postoperative motor and sensory deficits is unknown, and reconstruction aimed at restoring such deficits is infrequently carried out. OBJECTIVE: To identify the incidence and risk factors of postoperative morbidity in MPNST as well as the use and outcomes of functional reconstructions in these patients. METHODS: Postoperative function and treatment of MPNSTs diagnosed from 1988 to 2019 in 10 cancer centers was obtained. Two models were constructed evaluating factors independently associated with postoperative motor (