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William B. Borden and Rafael J. Tamargo

✓ George J. Heuer was a pioneer in neurosurgery at The Johns Hopkins Hospital in the early 20th century; he trained under Harvey Cushing and acted as a mentor to Walter Dandy. In his early career, Heuer focused on research and clinical work in the field of neurosurgery and temporarily led the neurosurgery section at Johns Hopkins. One of his most important contributions to neurosurgery was the modern frontotemporal craniotomy. This elegant craniotomy, which initially was used to approach chiasmal tumors, developed into the modern frontosphenotemporal craniotomy, which neurosurgeons use to approach numerous tumors as well as most aneurysms. Although Dandy is frequently credited with inventing this operation, his article detailing the new approach clearly attributes its origin to Heuer, who was serving in World War I when the new technique was presented.

Although he had hoped to lead the neurosurgical section at Johns Hopkins permanently, he returned from military service to find that Dandy had been appointed to this position. Heuer subsequently advanced to a distinguished career in general surgery as the chairman of surgery at two institutions, and was known for his contributions to surgical education. Throughout his academic years, Heuer continued to operate on the nervous system and to perform spinal cord and peripheral nerve surgery. He played an important role along with Cushing and Dandy in the creation of neurosurgery as a specialty, but he is rarely given credit for this accomplishment. The authors describe Heuer's contributions to neurosurgery as well as his distinguished surgical career.

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Irving J. Sherman, Ryan M. Kretzer and Rafael J. Tamargo

✓ Walter Edward Dandy (1886–1946) began his surgical training at the Johns Hopkins Hospital in 1910 and joined the faculty in 1918. During the next 28 years at Johns Hopkins, Dandy established a neurosurgery residency training program that was initially part of the revolutionary surgical training system established by William S. Halsted but eventually became a separate entity. Dandy’s residents were part of his “Brain Team,” a highly efficient organization that allowed Dandy to perform over 1000 operations per year, not counting ventriculograms. This team also provided rigorous training in the Halsted mold for the neurosurgical residents. Although exacting and demanding, Dandy was universally admired by his residents and staff. This article describes Dandy’s neurosurgical residency program at Johns Hopkins, and provides personal recollections of training under Walter Dandy.

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Raymond I. Haroun, Daniele Rigamonti and Rafael J. Tamargo

✓ Although the recurrent artery of Heubner is one of the best known cerebral arteries, little has been written in the neurosurgical or anatomical literature about its discovery. The artery is of primary importance to cerebrovascular surgeons, who identify it during clipping of anterior communicating artery aneurysms. Johann Otto Leonhardt Heubner (1843–1926), who described this artery in 1872, is better known as the father of German pediatrics. He was appointed to the first professorship in Germany exclusively devoted to pediatrics at the Charité Children's Clinic of Berlin University. Although he initially studied internal medicine in Leipzig under Carl Reinhold August Wunderlich and Ernst Leberecht Wagner, his early research involved anatomical studies of the circulation of the brain, from which he described syphilitic endarteritis (Heubner's disease). Finding morphological studies inconclusive, he turned to more physiological experiments. Together with the physiologist Max Rubner, Heubner performed important studies on energy metabolism in infancy, creating the notion of the nutrition quotient. In this article the authors review Heubner's life and scientific discoveries.

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Rafael J. Tamargo, Jonathan I. Epstein and Henry Brem

✓ Three human glioma cell lines (TE-671 medulloblastoma, U-87 MG glioblastoma, and U-373 MG glioblastoma) were transplanted to the quadrigeminal cistern of the brain in 37 newborn Sprague-Dawley rats and to the subcutaneous space in 30 of their siblings. Two of the three gliomas (the TE-671 medulloblastoma and the U-87 MG glioblastoma) grew both intracranially and subcutaneously. The U-373 MG glioblastoma did not grow in either site. The resulting tumors expressed unique morphological features characteristic of their tissue of origin. The newborn rat represents a model for the heterologous transplantation of human gliomas, providing a biological window for the study of these lesions.

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Ryan M. Kretzer, Alexander L. Coon and Rafael J. Tamargo

Although Walter E. Dandy (1886–1946) is appropriately credited with the first surgical clipping of an intracranial aneurysm in 1937—a procedure that established the modern field of vascular neurosurgery—his numerous other contributions to this specialty are not as well known. Dandy can be credited with the first detailed description of the vein of Galen malformation, the first description of x-ray visualization of an intracranial aneurysm, the first characterization of basilar artery dolichoectasia, and the publication of the first comprehensive operative case series of arteriovenous malformations, cavernous malformations, and developmental venous anomalies. In addition, Dandy performed the first surgical trapping of a cavernous internal carotid artery (ICA) aneurysm by clipping the supraclinoid ICA and ligating the cervical ICA, and he also executed the first intracranial surgical clipping of the ICA to treat a carotid-cavernous fistula. In this article the authors describe Dandy's contributions to the field of vascular neurosurgery.

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Eric M. Oshiro, David A. Rini and Rafael J. Tamargo

✓ In patients with bilateral supratentorial aneurysms, surgical clipping of all aneurysms via a unilateral approach would obviate the need for a second operation. The authors conducted a microsurgical study in human cadaver heads to examine the contralateral exposure for four common aneurysm sites in the anterior circulation: the ophthalmic artery (OA) origin, the posterior communicating artery (PCoA) origin, the internal carotid artery (ICA) termination, and the middle cerebral artery (MCA) bifurcation. Frontotemporal craniotomies were performed in 16 cadavers to evaluate the corridor for exposure of these sites from the contralateral side. Morphometric data, including lengths and diameters of major arterial segments and optic nerves, were documented for anatomical correlation.

In this study, the contralateral OA origin was successfully exposed in 62% of specimens, the PCoA origin in 50%, the ICA bifurcation in 100%, and the MCA bifurcation in 62%. Exposure of the OA origin and, in some cases, the PCoA, required incision of the falciform ligament and mobilization of the contralateral optic nerve. Exposure of the MCA bifurcation was dependent on the length of the M1 segment, with successful exposure only when this segment was shorter than 14 mm. Implications for the contralateral approach to aneurysms at these sites are discussed and the microsurgical corridors for exposure are described.

For correlation with the anatomical study, a brief clinical review of patients with bilateral supratentorial aneurysms treated at The Johns Hopkins Hospital between 1992 and 1995 is presented. Guidelines for the contralateral approach to aneurysms are discussed with reference to the anatomical study and the clinical review.

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Eric M. Oshiro, David A. Rini and Rafael J. Tamargo

In patients with bilateral supratentorial aneurysms, surgical clipping of all aneurysms via a unilateral approach would obviate the need for a second operation. The authors conducted a microsurgical study in human cadaver heads to examine the contralateral exposure for four common aneurysm sites in the anterior circulation: the ophthalmic artery (OA) origin, the posterior communicating artery (PCoA) origin, the internal carotid artery (ICA) termination, and the middle cerebral artery (MCA) bifurcation. Frontotemporal craniotomies were performed in 16 cadavers to evaluate the corridor for exposure of these sites from the contralateral side. Morphometric data, including lengths and diameters of major arterial segments and optic nerves, were documented for anatomical correlation.

In this study, the contralateral OA origin was successfully exposed in 62% of specimens, the PCoA origin in 50%, the ICA bifurcation in 100%, and the MCA bifurcation in 62%. Exposure of the OA origin and, in some cases, the PCoA, required incision of the falciform ligament and mobilization of the contralateral optic nerve. Exposure of the MCA bifurcation was dependent on the length of the M1 segment, with successful exposure only when this segment was shorter than 14 mm. Implications for the contralateral approach to aneurysms at these sites are discussed and the microsurgical corridors for exposure are described.

For correlation with the anatomical study, a brief clinical review of patients with bilateral supratentorial aneurysms treated at The Johns Hopkins Hospital between 1992 and 1995 is presented. Guidelines for the contralateral approach to aneurysms are discussed with reference to the anatomical study and the clinical review.

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Matthew J. McGirt, Giannina L. Garces Ambrossi, Judy Huang and Rafael J. Tamargo

Object

Vasospasm is the major cause of disability and death after aneurysmal subarachnoid hemorrhage (aSAH). Although the results of 2 randomized clinical trials demonstrated that statin decreases the incidence of symptomatic cerebral vasospasm after aSAH, retrospective studies have failed to confirm this. The authors conducted a prospective observational study to determine whether a standardized regimen of simvastatin would reduce the incidence of cerebral vasospasm and improve neurological outcomes in patients with aSAH.

Methods

Since 1991, all patients with aSAH admitted to the authors' institution have been prospectively followed up with standardized outcomes recording. Starting in September 2005, all patients admitted with aSAH were given enteral simvastatin (80 mg/day for 14 days) in addition to the standard care. The incidence of symptomatic cerebral vasospasm, length of hospitalization, in-hospital mortality rate, and discharge Glasgow Outcome Scale scores in these 170 patients were compared to data obtained in 170 consecutive patients who underwent treatment in our unit prior to the introduction of statin therapy.

Results

The 5-year study period included 340 consecutively treated patients (170 who received statins and 170 who did not). Patients who received simvastatin therapy were more frequently male (29 vs 20%) and had a smaller median aneurysm diameter (6 vs 7 mm). Baseline characteristics were otherwise similar between the cohorts. There were no differences in the incidence of symptomatic vasospasm (25.3 vs 30.5%; p = 0.277), in-hospital mortality rate (18 vs 15%; p = 0.468), length of hospitalization (21 ± 15 vs 19 ± 12 days; p = 0.281), or poor outcome at discharge (Glasgow Outcome Scale Scores 1–2: 21.7 vs 18.2%; p = 0.416) between the simvastatin and nonstatin cohorts. There were no statin-related complications.

Conclusions

The uniform introduction of simvastatin did not reduce the incidence of symptomatic cerebral vasospasm, death, or poor outcome in patients with aSAH. Simvastatin was well tolerated, but its benefit may be less than has been previously reported.

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Ingrid M. Burger, Rafael J. Tamargo, Jennifer Broussard and Philippe Gailloud

✓The authors report on the case of a 28-year-old woman presenting with an intraosseous arteriovenous fistula (AVF) located in the left parietal bone. The fistula was formed by direct arteriovenous shunts connecting branches of the left middle meningeal and superficial temporal arteries with a parietal diploic vein. Drainage occurred through both the external and internal jugular venous systems. Therapy consisted of combined surgical and endovascular approaches. The results of a pathological examination of the resected AVF showed mild enlargement of the diploic space. The angiographic appearance, pathological anatomy, and treatment of this rare lesion are discussed, as is a possible relationship between diploic AVFs and the development of aneurysm bone cysts.

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Edison P. Valle, Rafael J. Tamargo and Philippe Gailloud

The cases of 2 children with true aneurysmal subarachnoid hemorrhages (SAHs) and initial false-negative angiograms are reported. In both cases, the initial angiogram was of adequate technical quality and included the projections on which aneurysms were later documented. There was no significant vasospasm at the time of initial angiography; therefore, transient aneurysm sac thrombosis was the most likely explanation for the initial false-negative studies. It is particularly interesting to note that 1 of the 2 patients had a pattern of hemorrhage compatible with the most limited definition of a perimesencephalic SAH, that is, a small prepontine cistern hemorrhage. If a second angiogram had been deemed unnecessary based on that criterion alone, a ruptured basilar tip aneurysm would have escaped detection and treatment.