Richard A. Prayson

Development of a synergistic case-based microanatomy curriculum.

This paper discusses the development of an interactive approach to teaching and assessing a microanatomy curriculum in an innovative medical school program. As an alternative to lectures and labs, students are engaged in interactive seminars focused on discussion of clinical and research‐based cases matched with normal histology and pathology slides. A virtual microscopic system is used rather than the traditional glass slide and light microscope. Evaluation of student performance consists of self‐assessment board style questions, concept appraisal problems, and utilization of a portfolio system where the assessment pieces are continuously integrated as part of written formative and summative assessments. Anat Sci Ed 1:102–105, 2008.

Frozen section discrepancy in the evaluation of nonneoplastic central nervous system samples

Frozen section (FS) for intraoperative evaluation of central nervous system (CNS) lesions provides the neurosurgeon with a rapid preliminary pathologic diagnosis. Diagnosis of nonneoplastic lesions is particularly challenging in this venue. To highlight common diagnostic pitfalls, we sought to identify discrepancies between FS and final diagnoses among nonneoplastic CNS samples via a retrospective review of 303 FS cases encountered from 1997 to 2006. Thirty-nine (12.9%) discrepant diagnoses were identified, of which 27 were clinically suspected tumors. Final diagnoses in the discrepant group included the following: inflammatory lesions (n = 8, 20.5%), malformation of cortical development-cortical dysplasia (n = 5, 12.8%), gliosis (n = 5, 12.8%), vascular malformations (n = 5, 12.8%), demyelination/progressive multifocal leukoencephalopathy (n = 3, 7.7%), infarct (n = 3, 7.7%), hemorrhage/blood clot (n = 3, 7.7%), and no pathologic changes (n = 3, 7.7%). The remaining 4 (10.2%) discrepant cases involved one case each of amyloid angiopathy, nonspecific vasculopathy, vasculitis, and meningioangiomatosis. Nonneoplastic lesions are often more challenging than neoplastic lesions at FS, particularly because they are less commonly sampled for FS and, therefore, less familiar to pathologists.

Supporting students in self-regulation: Use of formative feedback and portfolios in a problem-based learning setting

Background: The widely recognized need for students to self-regulate their behavior and learning extends to the multiple dimensions of professionalism. Aim: This study examines the extent to which students self-regulate professionalism behaviors related to work habits and interpersonal skills in a PBL setting. Methods: Formative feedback on works habits and interpersonal skills provided by peers and tutors to a Year 1 cohort (n = 32) over the course of a year-long PBL experience (5 blocks) was examined for comments on targeted areas for improvement (TAFIs) and observed improvements. We examined congruence between PBL feedback and students’ self-reported TAFIs and behavioral improvements in their assessment portfolios. Results: Both PBL peer and faculty feedback and portfolio self-assessments targeted Interpersonal Skills TAFIs more frequently than Work Habit-related issues. TAFIs were more frequently identified midway in PBL blocks versus the end. Students reported TAFIs in their portfolio essays, citing feedback from both peers and tutors, and provided evidence of improved performance over time. Conclusions: Students utilized external formative feedback to document their portfolio self-assessment in a system designed to support self-regulation of PBL professionalism-related behaviors. A decrease in TAFIs identified at the end of PBL blocks suggests students made use of mid-block feedback to self-regulate behaviors.

Hippocampal sclerosis and associated focal cortical dysplasia-related epilepsy in neurofibromatosis type I

Neurofibromatosis type I (NF1) is a relatively common disorder associated with a range of neurologic sequelae. Refractory epilepsy occurs in 4-13% of NF1 patients. Hippocampal sclerosis and focal cortical dysplasia, both well-defined epilepsy-related entities, have been described in a subset of cases. To our knowledge, there has been only one other series describing coexistent focal cortical dysplasia and hippocampal sclerosis in the setting of NF1. We report two such patients who presented with intractable seizures requiring epilepsy surgery. Histologically, the hippocampal sclerosis specimen met criteria for the International League Against Epilepsy (ILAE) hippocampal sclerosis subtypes Ia and II respectively. The associated focal cortical dysplasia observed within the resected temporal lobe were both consistent with ILAE focal cortical dysplasia type IIIa (e.g. associated with a secondary lesion). Post-operatively, both patients had recurrence of habitual seizures, with one case continuing to have intractable seizures following two subsequent temporal lobectomies. Although hippocampal sclerosis association with focal cortical dysplasia is well document in epilepsy, it has been rarely described in the setting of neurofibromatosis type I. Although prior surgical series have shown good epilepsy surgery outcomes within neurofibromatosis type I, these two cases did not.

Primary Hodgkin lymphoma of the central nervous system.

Primary involvement of the central nervous system by Hodgkin lymphoma is rare; most cases represent metastases. We report a primary Hodgkin lymphoma presenting in the cerebellum of a 77-year-old man and review the literature on primary Hodgkin lymphoma of the central nervous system.

Coexistent ganglioglioma, focal cortical dysplasia, and hippocampal sclerosis (triple pathology) in chronic epilepsy.

The most commonly identified pathologies in patients with medically intractable epilepsy include focal cortical dysplasia, hippocampal sclerosis, tumors, and remote ischemic damage. Surgery has proven to be an effective therapeutic modality in most of such patients. The coexistence of multiple pathologies in resected tissues is well documented, particularly ganglioglioma and focal cortical dysplasia. Cases of triple pathology are, however, extraordinarily unusual. We report 2 cases of triple pathology including hippocampal sclerosis, ganglioglioma, and focal cortical dysplasia. Cases of pathologically confirmed hippocampal sclerosis diagnosed between January 2000 to December 2012 (n= 349) were reviewed, and only 2 cases (0.6%) with triple pathology were identified. The histopathologic and clinical features of these 2 cases are reviewed. The patients included a 6-year-old girl and 10-year-old boy. The former patient presented with a 4-year history of epilepsy and oppositional defiant disorder. Imaging identified a lesion in the left parahippocampal gyrus and posterior hippocampus. The latter patient presented with an 8-year history of epilepsy, attention deficient hyperactivity disease, and a pervasive developmental disorder. Imaging identified a lesion in the left posterior temporal and occipital region. Resected tissues in both patients showed a ganglioglioma (World Health Organization grade I) with accompanying focal cortical dysplasia and hippocampal sclerosis. Both patients were seizure free on antiepileptic medication at last follow-up at 20 and 38 months, respectively. The prevalence of triple pathology including hippocampal sclerosis is low (<1% in the current study). Surgical intervention for triple pathology cases anecdotally appears effective in achieving seizure control.

Pediatric cerebral ganglioneuroblastoma

We describe a 4-year-old girl with acute onset headaches and transient blindness who underwent surgical intervention, chemotherapy, and radiotherapy for an intracranial mass. This mass was pathologically confirmed as a primary intracranial ganglioneuroblastoma, a rare finding in the pediatric population. The literature on pediatric primary intracranial ganglioneuroblastoma is reviewed.

Relapsing polymyositis in chronic graft versus host disease

Chronic graft versus host disease (GVHD) is a major complication of allogeneic hematopoietic stem cell transplantation, which contributes to the morbidity and mortality of transplant patients. A polymyositis pattern of injury is a rare manifestation of chronic GVHD in skeletal muscle after hematopoietic stem cell transplantation. We report a 54-year-old man with acute myeloid lymphoma who underwent an allogeneic bone marrow transplantation and subsequently developed acute gastrointestinal GVHD 2 months post-transplantation and polymyositis 14 months post-transplantation. Upon tapering of steroids, the patient experienced a relapse of polymyositis. The literature on polymyositis in chronic GVHD is briefly reviewed.

Chronic inflammation in refractory hippocampal sclerosis-related temporal lobe epilepsy

Emerging evidence suggests chronic inflammation may play a role in hippocampal sclerosis-associated temporal lobe epilepsy. We sought to systematically evaluate for its presence in a group of 315 patients who underwent surgery for medically-refractory epilepsy and who had hippocampal sclerosis. Upon histologic review of hematoxylin and eosin stained tissue sections, 95 (41%) cases demonstrated the presence of lymphocytes within the perivascular region and diffusely within the brain parenchyma. Those cases with chronic inflammation evident on hematoxylin and eosin staining were significantly more likely to experience a post-operative seizure recurrence than those without it (p=0.03). In 9 cases of hippocampi with chronic inflammation observed on hematoxylin and eosin stained sections, there was a mixture of both T (CD3+) and B (CD20+) lymphocytes located around blood vessels and interspersed within the brain parenchyma and a predominance of CD4 positive T cells versus CD8 positive cells. Ten hippocampi, apparently devoid of chronic inflammation upon inspection with hematoxylin and eosin stained sections, were stained with the lymphocyte common antigen CD45. In all 10 cases, scattered lymphoid cells were observed in the brain parenchyma, suggesting some level of chronic inflammation may be present in more cases than casual inspection might suggest. This study was the first to evaluate the incidence of chronic inflammation within a large temporal lobe epilepsy population. The study findings suggest chronic inflammation may be a more common component of hippocampal sclerosis -associated temporal lobe epilepsy than previously believed.

Multiple myeloma presenting with unilateral abducens and trigeminal nerve palsies.

Petrous apex masses can manifest with neurologic symptoms due to their involvement of various structures, including cranial nerves (CN) V and VI. The differential diagnosis of petrous masses is broad and includes a variety of both non-neoplastic and neoplastic lesions. We report a rare case of multiple myeloma confined to the right petrous apex, presenting with ipsilateral abducens and trigeminal nerve palsies. A 63-year-old woman presented with a 6-8 week history of facial numbness and a 2 week history of diplopia, with examination showing right-sided facial hypoesthesia in the CN V1-V3 region and right-sided lateral rectus palsy. MRI of the brain showed a solitary 2.0 cm lesion confined to the right petrous apex involving the right cavernous internal carotid artery and Meckels cave. A transnasal biopsy showed a proliferation of plasmacytoid cells, which showed diffuse immunoreactivity with antibodies to CD138 and kappa, consistent with a plasma cell dyscrasia. A bone scan subsequently revealed multiple lytic bone lesions involving the skull, left humerus, bilateral femurs and possibly the L4 vertebral body. Bone marrow biopsy and serum laboratory results confirmed the diagnosis of kappa-type multiple myeloma. Although rare, multiple myeloma may initially present with petrous involvement and associated cranial nerve deficits.