Peter W. Carmel

Analysis of the readability of patient education materials from surgical subspecialties

Patients are increasingly using the Internet as a source of information on medical conditions. Because the average American adult reads at a 7th‐ to 8th‐grade level, the National Institutes of Health recommend that patient education material be written between a 4th‐ and 6th‐grade level. In this study, we assess and compare the readability of patient education materials on major surgical subspecialty Web sites relative to otolaryngology.

Surgical nuances for removal of retrochiasmatic craniopharyngiomas via the transbasal subfrontal translamina terminalis approach.

Giant craniopharyngiomas in the retrochiasmatic space are challenging tumors, given the location and surrounding vital structures. Surgical removal remains the first line of therapy and offers the best chance of cure. For tumors with extension into the retrochiasmatic space, the authors use the translamina terminalis corridor via the transbasal subfrontal approach. Although the lamina terminalis can be accessed via anterolateral approaches (pterional or orbitozygomatic), the surgical view of the optic chiasm is oblique and prevents adequate visualization of the ipsilateral wall of the third ventricle. The transbasal subfrontal approach, on the other hand, offers the major advantage of direct midline orientation and access to the third ventricle through the lamina terminalis. This provides the significant advantage of visualization of both walls of the third ventricle and hypothalamus as well as inferior midline access to the interpeduncular cistern to permit safe neurovascular dissection and total tumor removal. In this report, the authors describe the transbasal subfrontal translamina terminalis approach, with specific emphasis on technical surgical nuances in removing retrochiasmatic craniopharyngiomas. An illustrative video demonstrating the technique is also presented.

Molecular oncogenesis of craniopharyngioma: current and future strategies for the development of targeted therapies

Craniopharyngiomas are benign intracranial tumors that arise in the suprasellar and intrasellar region in children and adults. They are associated with calcification on neuroimaging, endocrinopathies, vision problems, and recurrence following subtotal resection. Molecular studies into their genetic basis have been limited, and therefore targeted medical therapies for this tumor have eluded physicians. With the discovery of aberrant Wnt/β-catenin pathway signaling in the pathogenesis of the most common subtype of craniopharyngioma (adamantinomatous), the identification of candidate genes and proteins implicated in this cascade provide attractive targets for future therapies. The recent development of a genetically engineered animal model of this tumor may also serve as a platform for evaluating potential therapies prior to clinical trials in humans. Advances in understanding the molecular pathogenesis of tumor recurrence have also been made, providing clues to develop adjuvant and neoadjuvant therapies to couple with tumor resection for optimal response rates. Finally, advances in genomic technologies and next-generation sequencing will underlie the translation of these genetic and molecular studies from the bench to clinical practice. In this review, the authors present an analysis of the molecular oncogenesis of craniopharyngioma and current directions in the development of novel therapies for these morbid, yet poorly understood brain tumors.

Lipomyelomeningocele: pathology, treatment, and outcomes.

Lipomyelomeningocele represents a rare but complex neurological disorder that may present with neurological deterioration secondary to an inherent tethered spinal cord. Radiological testing is beneficial in determining the morphology of the malformation. Specialized testing such as urodynamic studies and neurophysiological testing may be beneficial in assessing for neurological dysfunction secondary to the lipomyelomeningocele. Early surgical intervention may be beneficial in preventing further neurological decline.

The use of Hypertonic Saline in the Treatment of Post-Traumatic Cerebral Edema: A Review

Effective methods for treating cerebral edema have recently become a matter of both extensive research and significant debate within the neurosurgery and trauma surgery communities. The pathophysiologic progression and outcome of different forms of cerebral edema associated with traumatic brain injury have yet to be fully elucidated. There are heterogeneous factors influencing the onset and progress of post-traumatic cerebral edema, including the magnitude and type of head injury, age, co-morbid conditions of the patient, the critical window for therapeutic intervention and the presence of secondary insults including hypoxia, hypotension, hypo/hyperthermia, degree of raised intracranial pressure (ICP), and disruption of blood brain barrier (BBB) integrity. Although numerous studies have been designed to improve our understanding of the etiology of post-traumatic cerebral edema, therapeutic interventions have traditionally been focused on minimizing secondary insults especially raised ICP and improving cerebral perfusion pressure. More recently, fluid resuscitation strategies using hyperosmolar agents such as pentastarch and hypertonic saline (HS) have achieved some success. HS treatment is of particular interest due to its apparent advantageous action over other types of hyper-osmotic solutions in both clinical and laboratory studies. In this review, we provide a summary of recent literature concerning the pathogenesis and mechanisms involved in the various types of cerebral edema, and the possible mechanisms of action of HS for the treatment cerebral edema.

Microscopic versus endoscopic approaches for craniopharyngiomas: choosing the optimal surgical corridor for maximizing extent of resection and complication avoidance using a personalized, tailored approach

Resection remains the mainstay of treatment for craniopharyngiomas with the goal of radical resection, if safely possible, to minimize the rate of recurrence. Endoscopic endonasal and microscopic transcranial surgical approaches have both become standard methods for the treatment for craniopharyngiomas. However, the approach selection paradigm for craniopharyngiomas is still a point of discussion. Choosing the optimal surgical approach can play a significant role in maximizing the extent of resection and surgical outcome while minimizing the risks of potential complications. Craniopharyngiomas can present with a variety of different sizes, locations, and tumor consistencies, and each individual tumor has distinct features that favor one specific approach over another. The authors review standard cranial base techniques applied to craniopharyngioma surgery, using both the endoscopic endonasal approach and traditional open microsurgical approaches, and analyze factors involved in approach selection. They discuss their philosophy of approach selection based on the location and extent of the tumor on preoperative imaging as well as the advantages and limitations of each surgical corridor, and they describe the operative nuances of each technique, using a personalized, tailored approach to the individual patient with illustrative cases and videos.

Pierre Curie: the anonymous neurosurgical contributor

Pierre Curie, best known as a Nobel Laureate in Physics for his co-contributions to the field of radioactivity alongside research partner and wife Marie Curie, died suddenly in 1906 from a street accident in Paris. Tragically, his skull was crushed under the wheel of a horse-drawn carriage. This article attempts to honor the life and achievements of Pierre Curie, whose trailblazing work in radioactivity and piezoelectricity set into motion a wide range of technological developments that have culminated in the advent of numerous techniques used in neurological surgery today. These innovations include brachytherapy, Gamma Knife radiosurgery, focused ultrasound, and haptic feedback in robotic surgery.

Monitoring papilledema in a patient with pineal pilocytic astrocytoma by using Heidelberg Retina Tomograph II. Case report.

The Heidelberg Retina Tomograph (HRT) II is a confocal scanning laser device used to acquire images of the optic nerve head. In this paper the authors report a novel use of this device in the assessment of papilledema in a patient with pilocytic astrocytoma of the pineal region. They also present a new technique to objectively produce 3D data of the optic nerve head. An 11-year-old girl presented with headache and bilateral papilledema; magnetic resonance imaging revealed a lesion in the pineal region. A suboccipital craniectomy was performed, and HRT images were obtained both before (baseline) and after (follow-up) the operation. The authors analyzed the height variation of the retinal surface along the vertical and horizontal cross-lines passing the center of the optic nerve head. The postoperative images, studied on the 2nd day after operation, demonstrated visible reduction of the papilledema. The height variation of the retinal surface along the contour line created by the software demonstrated that elevation of the optic nerve head became depressed due to resolved swelling. The height variation of the retinal surface along vertical and horizontal cross-lines demonstrated significant differences between the elevated preoperative curve and the postoperative curve (p < 0.001), consistent with improvement of her symptoms. Initial data suggest that changes in the optic nerve head topography after surgical decompression can be quantitatively documented by 3D data from the HRT II.

Radical Removal of Craniopharyngiomas 1971–1991

Craniopharyngiomas are histologically benign tumors that may be lethal if incompletely treated. Our attempts at radical removal of these tumors owe much to the work of Dr. William Sweet (1988) who showed that the projections of tumor that extend into neural tissue are actually surrounded by a thick glial layer. Splitting of this glial layer permits removal of the tumor while preserving the neural structures.

Joseph Warren: a discussion of his life and analysis of his death

As his fellow soldiers ran past him, Joseph Warren stood bravely on Bunker Hill. It was June 17, 1775, and British troops were fighting the colonists in one of the early battles of the American Revolution. The British had already attempted two major assaults that day, and the third would end with Warrens death. He was a medical doctor, public figure, and general who spent his life and last living moments fighting for freedom for the American colonists. After the battle, there was much confusion about what had happened to Joseph Warren. Some thought he had survived the battle; other accounts differed on how exactly he had died. The details of the events on Bunker Hill remained a mystery until the following year, when Paul Revere helped identify Warrens body by the false teeth that had been implanted years earlier. Warrens remains showed that his head had been struck by a bullet. Analysis of the skull helped to sift through the differing tales of Warrens death and thus unveil the truth about what occurred that day. The smaller bullet wound in the left maxilla suggests that he was not shot while retreating with the rest of the soldiers. The larger exit wound in the right occiput illustrates that the bullets trajectory crossed the midline of the brain and most likely injured the brainstem. Therefore, contrary to rumors that circulated at the time, Joseph Warren most likely was killed instantly at the Battle of Bunker Hill while heroically facing his enemy.