Venous Thromboembolic Events in Adult Trauma Patients Receiving Balanced Hemostatic Resuscitation (BHR): An Analysis of Their Incidence, Predictors, and Associated Mortality Rates at a Level 1 Trauma Center.

Background and objective Studies assessing the incidence of venous thromboembolic (VTE) events in the setting of massive balanced transfusions and/or tranexamic acid (TXA) infusion have yielded varied outcomes. In light of this, we conducted this study to examine the incidence of VTEs in trauma patients requiring blood products, and to identify the risk factors for VTE and mortality in this population. Methods We performed a retrospective analysis of trauma patients admitted to our level 1 trauma center from January 2013 to September 2023. Clinical characteristics were compared between patients who developed VTE and those who did not. A regression analysis of potential variables associated with the development of VTEs and mortality was performed. Results Among 1305 patients (mean age: 42.4 ± 18.8 years) receiving blood products within the initial 24 hours, 4.3% (56 patients) developed a VTE. Patients with VTE experienced prolonged ICU and hospital stays and ventilation duration (p<0.001). They were also noted to have delayed initiation of VTE prophylaxis (104.2 vs. 50.3 hours, p<.001). Prolonged ventilation >7 days was the sole significant factor associated with VTE in multivariate regression analysis [odds ratio (OR): 6.2, p=0.004]. Early TXA administration (within four hours) showed a higher association with VTE than TXA within 24 hours (OR: 2.1, p=0.07 vs. OR 1.6, p=0.22). Massive transfusion was found to increase VTE risk (OR: 2.65, p<0.001). Severe head and neck (OR: 6.0, p=0.002) and chest (OR: 3.8, p=0.01) injuries were key predictors of mortality, while TXA was not significantly associated with mortality in the multivariate model. Conclusions Our study revealed an elevated risk of VTE in patients requiring massive transfusion protocol (MTP, ≥6 units). Early TXA administration was neither associated with increased VTE risk in MTP patients nor increased mortality risk. Strategies directed at reducing the risk of VTE in massively transfused patients while maintaining the survival benefits of balanced resuscitation and TXA need to be devised.

The Role of Neuropsychology in Traumatic Brain Injury: Comprehensive Literature Review.

Traumatic brain injury (TBI) is a major public health concern, often leading to significant behavioral and cognitive changes with subsequent impairment in daily functioning and personal interactions. The management of TBI involves a multidisciplinary approach. Neuropsychology has emerged as a critical discipline in assessing, diagnosing, treating, and rehabilitating individuals with TBI. Successful management also requires careful consideration of the patient's cognitive status. Therefore, clinicians must have a comprehensive understanding of the overall clinical picture of the patient at the cognitive and physical level. The primary aim of this research is to explore the role of neuropsychology in TBI management and rehabilitation thoroughly while providing an updated review of the literature. Various neuropsychological assessment tools used to evaluate cognitive functioning in individuals with TBI will be discussed in addition to their validity, reliability, and usefulness in identifying cognitive deficits and developing individualized treatment plans. The findings in this article will have significant implications on the clinical practice of neuropsychology in TBI patients, highlighting the importance of neuropsychological assessment in optimizing the management of this population. The need for increased awareness of neuropsychology among health care professionals, especially in the acute hospital setting, is growing along with the increase in diagnosis of TBI and its complications. Adequate understanding of the complex interplay between cognitive, emotional, and behavioral factors in TBI can inform the development of new interventions and treatment strategies, making it equally as important for patients and their families.

Advanced Neck Dermatillomania Leading to Cervical Osteomyelitis and Epidural Abscess.

Dermatillomania, a condition characterized by compulsive skin picking, can lead to tissue damage and severe infections of adjacent structures. This case report presents the first documented instance of dermatillomania-induced cervical osteomyelitis and epidural abscess. Herein, we describe the case of a 45-year-old male patient with a history of a non-healing posterior neck wound, which progressively worsened and extended to the posterior cervical spine. The patient subsequently experienced weakness and paresthesia in the left arm. Neuroimaging revealed cervical spine osteomyelitis and an associated epidural collection/phlegmon compressing the spinal cord. The abscess was evacuated via posterior laminectomy, followed by culture-guided antibiotic therapy. The presence of a chronic wound or ulcer in the setting of psychiatric comorbidities should raise suspicion of dermatillomania-induced complications. Early diagnosis is essential to guide management and prevent serious complications. Management involves a multidisciplinary approach that includes addressing behavioral abnormalities and concurrent psychiatric disorders.

Predictors of Surgical Outcomes in Patients with Abducens Nerve Schwannoma: A Comprehensive Systematic Review and a Case Report.

BACKGROUND: Abducens nerve (AN) schwannomas are extremely rare tumors. Clinical characteristics and factors that influence postoperative outcomes are not well defined. OBJECTIVE: To characterize clinical features of AN schwannomas and predictors of surgical outcomes. METHODS: PRISMA-guided systematic review of the literature on AN schwannomas was performed. Subsequently, univariate and multivariate regression analyses were performed to identify the predictive value of variables that influence postoperative outcomes. RESULTS: A total of 42 studies with 55 patients were evaluated. The mean age at presentation was 43.9 ± 14.6 years. The most common presenting symptom was cranial nerve VI palsy (69.1%). Cavernous sinus (49.1%) and prepontine cistern (36.3%) were the most commonly involved locations. Complete recovery after surgery was seen in 36.3% at a median follow-up of 28.4 ± 25.8 months. Preoperative AN palsy (P < 0.001), suboccipital approach (P = 0.007), and subtotal resection of tumor (P = 0.044) were significant protective factors for postoperative complications. Prepontine location and postoperative complications were poor prognostic indicators of AN recovery (odds ratio [OR], 0.10, P = 0.030 and OR, 0.10, P = 0.028, respectively). Subtotal resection was significantly correlated with higher odds of AN recovery (OR, 6.06; P = 0.040). CONCLUSIONS: AN schwannomas are rare but serious tumors that can cause significant morbidity, with only approximately one third of patients showing complete recovery after surgery. The suboccipital approach was a protective factor for postoperative complications, especially when combined with subtotal resection. Knowledge of these factors along with tumor characteristics helps optimize surgical planning and preoperative counseling.

Brain Meningiomas Manifesting as Intracranial Hemorrhage: Comprehensive Systematic Review and Report of the First Case of Hemorrhagic Meningiomatosis.

OBJECTIVE: To characterize the salient features of hemorrhagic manifestation of meningiomas and to report on the first case of hemorrhagic meningiomatosis. METHODS: A comprehensive systematic review of the English-language literature was performed using MEDLINE, PubMed, and Google Scholar databases to identify case reports and series of brain meningiomas manifesting as intracranial hemorrhage. RESULTS: A total of 65 patients were evaluated. Most patients were female (64.6%). The average age at presentation was 58.1 ± 14.3 years. The most common presenting symptom was focal neurologic deficits (n = 47; 71.2%). Identification of tumor was missed/not possible in 24.6% of patients. The most common reported comorbidity was hypertension. Most tumors were located in convexity (n = 36; 55.3%). Subdural hematoma (± other hemorrhages) was the most common type of intracranial hemorrhage (n = 46; 70.7%). Computed tomography hyperintensity (25.7%) and magnetic resonance imaging T2 hypointensity (22%) were the most prevalent radiologic findings. The predominant histopathology subtype was meningothelial (syncytial) (n = 24; 36.4%). The estimated mortality was 13.8%. Among those who survived, 39.9% had residual deficits at a median follow-up of 8.1 ± 5.8 months. CONCLUSIONS: Intracranial hemorrhage induced by meningiomas is associated with significant mortality and morbidity. Identifying unexpected meningioma in the setting of intracranial bleed can help optimize preoperative planning (e.g., surgical approach) and facilitate total resection of the underlying tumor. Therefore, clinicians should have a high index of suspicion with a low threshold for investigation of meningiomas in the setting of intracranial hemorrhage.

The Surgical Management of Holospinal Epidural Abscess: A Case Report and Review on Catheter-Based Irrigation Techniques.

Holospinal epidural abscess (HEA) is an extremely rare spinal infection involving the entire spine and is infrequently reported in the literature. Cases with evidence of spinal cord compression and consequent neurological deficit are typically managed with prompt surgical drainage and broad-spectrum antibiotics. Surgical intervention is often challenging because this condition is inherently associated with poor prognosis and serious complications, including death. During the surgical evacuation of the abscess, catheter-based irrigation must be adequately performed. In the majority of reported cases, the extent of the advancement of the epidural catheter is blindly assessed by the operating surgeon, increasing the risk of residual collections and subsequent persistent infection. Herein, we report a rare case of HEA that was successfully treated with surgical evacuation and skip laminectomies. We also describe a catheter-based technique that facilitates adequate irrigation, thereby ensuring the complete drainage of HEA in obscured perispinal areas, as well as the decompression of the spinal cord. Postoperative neurological examination exhibited marked improvement in motor function (compared with a baseline of complete quadriparesis), indicating the successful decompression of the spinal cord and neurological improvement.

Intracranial Subdural Hematoma Versus Postdural Puncture Headache Following Epidural Anesthesia: A Case Report.

Headache is a relatively common complaint following dural puncture whether it is diagnostic (lumbar puncture) or unintentional (e.g., after epidural anesthesia). Although postdural puncture headache (PDPH) turns out to be the culprit in many cases, other serious etiologies should be ruled out such as postepidural intracranial subdural hematoma (PEISH). PEISH is usually overlooked because it is relatively rare and due to other frequent causes of headache (e.g., tension headache, migraine, and PDPH) being the main consideration. PEISH can be easily misdiagnosed as PDPH because of similar clinical manifestations. Herein, we report a case of this rare complication and demonstrate the major differences between PDPH and PEISH. This 27-year-old woman with intrauterine fetal death of dizygotic twins complained of severe headache immediately following receiving epidural anesthesia for labor induction. The patient was initially diagnosed with PDPH, and a blood patch was placed which provided complete resolution of the headache only for two days. Computed tomography of the brain revealed a small subdural hematoma over the left frontal convexity. Conservative management with close monitoring was recommended in this case due to the small size of the hematoma and absence of intracranial mass effect. An early follow-up CT scan showed complete and spontaneous resolution of the hematoma. In patients with recurrence or change in the pattern of the headache, persistence of headache despite treatment, and presence of neurological dysfunction following epidural anesthesia, suspicion of intracranial etiology must be raised. Therefore, knowledge of this condition and differentiating it from PDPH is necessary to avoid misdiagnosis and futile attempts of treatment.

Use of Dental Bisphenol A-Glycidyl Methacrylate Composite to Repair Refractory Cerebrospinal Fluid Leaks Associated With Large-Scale Anterior Skull Base Defects.

ABSTRACT: Treatment of refractory cerebrospinal fluid (CSF) leaks, particularly those associated with large skull base defects, is challenging. A variety of synthetic biomaterial-based systems have been investigated in experimental models and/or humans for reconstructing cranial base defects. A widely used dental composite (bisphenol A-glycidyl methacrylate [bis-GMA]) has been shown to be effective for reconstruction of anterior skull base defects in animal models. Here, we report 4 patients who underwent reconstruction of large anterior skull base defects (1405.8 ±â€Š511 mm2) secondary to tumor resection and traumatic injury using the dental bis-GMA resin-based composite. A vascularized pericranial flap with fibrin glue was initially performed in all patients with concurrent use of dental bis-GMA during the primary surgery in 2 patients, and later use (in a repeat surgery) in other 2 cases. In these latter 2, CSF rhinorrhea persisted after the initial surgery (in the absence of bis-GMA use) despite external CSF drainage with lumbar drain. Following treatment with bis-GMA, rigid structural support and watertight closure of the defect were successfully achieved. At the follow-up, CSF leak did not recur and none of the patients had any complications related to the surgery or the composite. The results obtained from this series are promising, and dental bis-GMA resin seems to provide an effective and feasible material for the treatment and prevention of CSF leaks related to large-scale anterior skull base defects. However, further studies with longer clinical follow-up and larger number of patients are required to prove the safety and efficacy of this matrix in the long run.

Anatomical Variations That Can Lead to Spine Surgery at the Wrong Level: Part III Lumbosacral Spine.

Spine surgery at the wrong level is an undesirable event and unique pitfall in spine surgery. It is detrimental to the relationship between the patient and the surgeon and typically results in profound medical and legal consequences. It falls under the wrong-site surgery sentinel events reporting system. This error is most frequently observed in lumbosacral spine. Several risk factors are implicated; however, anatomical variations of the lumbosacral spine are a major risk factor. The aim of this article was to provide a detailed description of these high-risk anatomical variations, including transitional vertebrae, lumbar ribs, butterfly vertebrae, hemivertebra, block/fused vertebrae, and spinal dysraphism. A literature review was performed in the database PubMed to obtain all relative English-only articles concerning these anatomical variations and their implication in the development of lumbosacral spine surgery at the wrong level. We also described patient characteristics that can lead to lumbosacral surgery at the wrong level such as tumors, infection, previous lumbosacral surgery, obesity, and osteoporosis. Certain techniques to prevent such incorrect surgery were explained. Lumbosacral spine anatomical variations are surgically significant. Awareness of their existence may provide better pre-operative planning and surgical intervention, leading to avoidance of incorrect-level surgery and potentially better clinical outcomes. In addition, collaboration with radiologists and careful examination of patient's anatomy and characteristics should be exercised, especially in difficult cases.

Anatomical Variations That Can Lead to Spine Surgery at the Wrong Level: Part I, Cervical Spine.

Spine surgery at the wrong level is an adversity that many spine surgeons will encounter in their career, and it falls under the wrong-site surgery sentinel events reporting system. The cervical spine is the second most common location in the spine at which surgery is performed at the wrong level. Anatomical variations of the cervical spine are one of the most important incriminating risk factors. These anomalies include craniocervical junction abnormalities, cervical ribs, hemivertebrae, and block/fused vertebrae. In addition, patient characteristics, such as tumors, infection, previous cervical spine surgery, obesity, and osteoporosis, play an important role in the development of cervical surgery at the wrong level. These were described, and several effective techniques to prevent this error were provided. A thorough review of the English-language literature was performed in the database PubMed between 1981 and 2019 to review and summarize these risk factors. Compulsive attention to these factors is essential to ensure patient safety. Therefore, the surgeon must carefully review the patient's anatomy and characteristics through imaging and collaborate with radiologists to reduce the likelihood of performing cervical spine surgery at the wrong level.

Anatomical Variations That Can Lead to Spine Surgery at The Wrong Level: Part II Thoracic Spine.

Spine surgery at the wrong level is a detrimental ordeal for both surgeon and patient, and it falls under the wrong-site surgery sentinel events reporting system. While there are several methods designed to limit the incidence of these events, they continue to occur and can result in significant morbidity for the patient and malpractice lawsuits for the surgeon. In thoracic spine, numerous risk factors influence the development of this misadventure. These include anatomical variations such as transitional vertebrae, rib variants, hemivertebra, and block/fused vertebrae as well as patient characteristics, such as tumors, infections, previous thoracic spine surgery, obesity, and osteoporosis. An extensive literature search of the PubMed database up to 2019 was completed on each of the anatomical entities and their influence on developing thoracic spine surgery at the wrong level, taking into consideration patient's individual factors. A reliable protocol and effective techniques were described to prevent this error. In addition, the surgeon should collaborate with radiologists, particularly in challenging cases. A thorough understanding of the surgical anatomy and its variants coupled with patients characteristic is crucial for maximal patient benefit and avoidance of thoracic spine surgery at the wrong level.

The Neural Sulcus of the Cervical Vertebrae: A Review of Its Anatomy and Surgical Perspectives.

The neural sulcus is a bony channel that spans the transverse process in the subaxial cervical spine. It is located between the anterior and posterior tubercles on either side of the transverse foramen, housing the spinal nerve as it passes through the intervertebral foramina. Although numerous studies have evaluated the anatomy of the cervical spine, very little data on detailed anatomy of the neural sulcus and its implication in cervical spine surgery exist. Here, we review the anatomy of the neural sulcus and surgical considerations. The neural sulcus has important surgical implications, and knowledge of its anatomy is important in considering and planning posterior cervical segmented instrumentation. This increases the ability of the neurosurgeon to choose the best suitable surgical approach to the subaxial cervical spine, allowing good outcomes for the patient.

Quality and Clinical Care Development in Spine Surgery-Connecting the Dots: An Expanded Clinical Narrative.

Our health care system is an evidenced-based quality-centric environment. Pursuit of quality is a process that encompasses knowledge development and care advancements through collaboration and expertise. Depicted here is the foundational knowledge, process, and contributions that hallmark successful clinical quality programs. Beginning with methodology, followed by process and form, we create the foundational knowledge and exemplars demonstrating framework and continuum of process in pursuit and attainment of successful clinical quality and care development for patients. Although our protocol has been devised for complex spine care, this could be implemented across all health care specialties to provide individualized and high-quality care for all current and future patients, all while creating a culture of accountability for physicians.

Comparison of Lumbar Laminectomy Alone, Lumbar Laminectomy and Fusion, Stand-alone Anterior Lumbar Interbody Fusion, and Stand-alone Lateral Lumbar Interbody Fusion for Treatment of Lumbar Spinal Stenosis: A Review of the Literature.

Lumbar spinal stenosis is defined as narrowing of the lumbar spinal canal, which causes compression of the spinal cord and nerves. Spinal stenosis can cause leg pain and potentially back pain that can affect the quality of life. Ultimately, surgical decompression is required to alleviate the symptoms. In this review, we first utilize several important studies to compare lumbar laminectomy alone versus lumbar laminectomy and fusion. We also compare the effectiveness of more novel surgical approaches, stand-alone anterior lumbar interbody fusion (ALIF), and stand-alone lateral lumbar interbody fusion (LLIF). These techniques have their own advantages and disadvantages in which many factors must be taken into account before choosing a surgical approach. In addition, the patient's anatomy and pathology, lifestyle, and desires should be analyzed to help determine the ideal surgical strategy.

Cervical spondylodiscitis caused by Candida albicans in a non-immunocompromised patient: A case report and review of literature.

BACKGROUND: Fungal cervical spondylodiscitis is rare and accounts for less than 1% of all cervical, thoracic, and lumbar vertebral osteomyelitis and discitis. CASE DESCRIPTION: A 32-year-old non-immunocompromised male presented with persistent neck pain and paresthesias. The magnetic resonance imaging of the cervical spine demonstrated a contrast-enhancing erosive lesion involving the cervical C6 and C7 vertebral bodies accompanied by epidural phlegmon. Blood culture was negative. The patient underwent a C6 and C7 anterior corpectomy with instrumented fusion (e.g., expandable cage C5 to T1). Intraoperatively, frank pus was noted within the C6-C7 disc space and was accompanied by thick prevertebral and epidural phlegmon extending from C5 to T1. Intraoperative cultures grew Candida albicans. Three days later, a C6-C7 laminectomy with C4-T2 posterior instrumented fusion was performed; the cultures again grew C. albicans. The patient was treated with intravenous micafungin for 14 days followed by 6-12 months of 400 mg oral fluconazole daily. CONCLUSION: There are few cases in literature where non-immunocompromised patients developed fungal cervical spondylodiscitis. Prompt diagnosis and appropriate management are critical to effectively treat these patients. Surgical intervention may warrant corpectomy, discectomy, and operative debridement followed by long-term targeted antifungal therapy.

Reattachment of the Multifidus Tendon in Lumbar Surgery to Decrease Postoperative Back Pain: A Technical Note.

The posterior midline approach to the lumbar spine requires significant manipulation of the paraspinal muscles. Muscle detachment and retraction results in iatrogenic damage such as crush injury, devascularization, and denervation, all of which have been associated with postoperative pain. The muscle most directly affected by the posterior approach is the lumbar multifidus (LM), the largest and most medial of the deep lumbar paraspinal muscles. The effects of the posterior approach on the integrity of the LM is concerning, as multiple studies have demonstrated that intraoperative injuries sustained by the LM lead to postoperative muscle atrophy and potentially worsening low back pain. Given the inevitability of intraoperative paraspinal muscle manipulation when using the posterior approach, this technical note describes methods by which surgeons may minimize LM tissue disruption and restore the anatomical position of the LM to ultimately expedite recovery, minimize postoperative pain, and improve patient satisfaction.

Delayed Cerebral Ischemia of the Corpus Callosum: A Case Report.

Ischemic infarction of the corpus callosum is a rare condition due to its rich vascular supply and therefore has been infrequently reported. Here, we present a case of a patient who developed a delayed infarct of the corpus callosum in the body. The condition was characterized by bilateral lower extremity weakness and visual disturbances following intraventricular hemorrhage managed with ventriculostomy. Understanding the anatomy and function of the corpus callosum is crucial to understanding the etiology of infarctions as well as their clinical significance. It is also essential to distinguish between relatively common post-shunting changes and true infarction and to recognize the limited consequences of corpus callosum infarction. Increased awareness of this rare infarct would help to prevent unnecessary interventions and increase the ability of the physician to provide optimal care for the patient.

Candida parapsilosis Infection of Ventriculoperitoneal Shunt in Adult: Case Report and Literature Review.

BACKGROUND: Candida parapsilosis is an incredibly rare cause of ventriculoperitoneal (VP) shunt infections, with only 1 adult case reported in the literature to date. CASE DESCRIPTION: We describe the case of a 45-year-old man admitted for a traumatic fall and subsequently treated with VP shunt placement for obstructive hydrocephalus secondary to a cerebellar contusion and intraventricular hemorrhage. Eight months following VP shunt placement, the patient presented with a 2-month history of clear fluid leakage through a dehiscent surgical abdominal wound overlying the distal VP shunt. Cerebrospinal fluid cultures were obtained and grew C. parapsilosis. The patient subsequently underwent VP shunt externalization and began antifungal treatment with intravenous liposomal amphotericin B. Cerebrospinal fluid studies continued to redemonstrate C. parapsilosis infection, for which VP shunt removal and external ventricular drain placement was performed. Three days into treatment with amphotericin B, he endured significant nephrotoxicity necessitating a switch to oral fluconazole. Following 3 weeks of oral fluconazole treatment with negative serial cerebrospinal fluid cultures, the patient underwent external ventricular drain removal and VP shunt insertion. Following the procedure and 22 total days of oral fluconazole treatment, our patient recovered well and was discharged to a rehabilitation facility in stable condition. CONCLUSIONS: In our report, we describe the clinical course of our patient and offer a review and analysis of the most up-to-date literature concerning C. parapsilosis shunt infections, as well as treatment guidelines for central nervous system candidiasis.

Extraforaminal compression of the L5 nerve: An anatomical study with application to failed posterior decompressive procedures.

This anatomical study was performed to elucidate the pertinent foraminal and lateral L5 nerve anatomy to enhance our understanding of possible neurologic causes of failed decompression surgery. Persistent extraforaminal L5 nerve compression is a possible cause of persistent symptoms following lumbosacral surgery. The amount of extraforaminal space for the L5 ventral ramus was examined in fifty adult human skeletons (100 sides). Based on morphology, the specimens were then categorized (types I-IV) on the basis of the bony space available for the nerve at this location. Next, 25 embalmed adult cadavers (50 sides) underwent bilateral dissection of the lower lateral lumbar region. The type of bony extraforaminal outlet was documented for each cadaver on the basis of our skeletal analysis. Lastly, segments (intra- and extra-foraminal) of the L5 ventral ramus were excised and examined histologically. Types I-IV outlets were found in 43, 31, 20 and 6 skeletal sides, respectively. For cadavers, 22,15, 10 and 3 sides were found to have types I-IV bony outlets, respectively. In cadavers, all type IV outlets and 70% of the type III bony configurations adjacent to the L5 ventral ramus had signs of neural irritation/injury including vascular hyalinization and increased fibrosis distal to the intervertebral foramen. No distal segments of type I and type II outlets showed histological signs of neural compromise. Patients with symptoms referable to L5 nerve compression for whom no proximal pathology is identified could warrant investigation of the more distal extraforaminal segment of this nerve.

Dynamic susceptibility contrast and dynamic contrast-enhanced MRI characteristics to distinguish microcystic meningiomas from traditional Grade I meningiomas and high-grade gliomas.

OBJECTIVE Microcystic meningioma (MM) is a meningioma variant with a multicystic appearance that may mimic intrinsic primary brain tumors and other nonmeningiomatous tumor types. Dynamic susceptibility contrast (DSC) and dynamic contrast-enhanced (DCE) MRI techniques provide imaging parameters that can differentiate these tumors according to hemodynamic and permeability characteristics with the potential to aid in preoperative identification of tumor type. METHODS The medical data of 18 patients with a histopathological diagnosis of MM were identified through a retrospective review of procedures performed between 2008 and 2012; DSC imaging data were available for 12 patients and DCE imaging data for 6. A subcohort of 12 patients with Grade I meningiomas (i.e., of meningoepithelial subtype) and 54 patients with Grade IV primary gliomas (i.e., astrocytomas) was also included, and all preoperative imaging sequences were analyzed. Clinical variables including patient sex, age, and surgical blood loss were also included in the analysis. Images were acquired at both 1.5 and 3.0 T. The DSC images were acquired at a temporal resolution of either 1500 msec (3.0 T) or 2000 msec (1.5 T). In all cases, parameters including normalized cerebral blood volume (CBV) and transfer coefficient (kTrans) were calculated with region-of-interest analysis of enhancing tumor volume. The normalized CBV and kTrans data from the patient groups were analyzed with 1-way ANOVA, and post hoc statistical comparisons among groups were conducted with the Bonferroni adjustment. RESULTS Preoperative DSC imaging indicated mean (± SD) normalized CBVs of 5.7 ± 2.2 ml for WHO Grade I meningiomas of the meningoepithelial subtype (n = 12), 4.8 ± 1.8 ml for Grade IV astrocytomas (n = 54), and 12.3 ± 3.8 ml for Grade I meningiomas of the MM subtype (n = 12). The normalized CBV measured within the enhancing portion of the tumor was significantly higher in the MM subtype than in typical meningiomas and Grade IV astrocytomas (p < 0.001 for both). Preoperative DCE imaging indicated mean kTrans values of 0.49 ± 0.20 min-1 in Grade I meningiomas of the meningoepithelial subtype (n = 12), 0.27 ± 0.12 min-1 for Grade IV astrocytomas (n = 54), and 1.35 ± 0.74 min-1 for Grade I meningiomas of the MM subtype (n = 6). The kTrans was significantly higher in the MM variants than in the corresponding nonmicrocystic Grade 1 meningiomas and Grade IV astrocytomas (p < 0.001 for both). Intraoperative blood loss tended to increase with increased normalized CBV (R = 0.45, p = 0.085). CONCLUSIONS An enhancing cystic lesion with a normalized CBV greater than 10.3 ml or a kTrans greater than 0.88 min-1 should prompt radiologists and surgeons to consider the diagnosis of MM rather than traditional Grade I meningioma or high-grade glioma in planning surgical care. Higher normalized CBVs tend to be associated with increased intraoperative blood loss.