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  • By Author: Machinis, Theofilos G. x
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Kostas N. Fountas, Eftychia Z. Kapsalaki, Gregory P. Lee, Theofilos G. Machinis, Arthur A. Grigorian, Joe S. Robinson Jr., Ioannis Vergados and Panagiotis G. Theodosiadis

Object

The association of vitreous and/or subhyaloid hemorrhage with aneurysmal subarachnoid hemorrhage (SAH) has been frequently identified since the original description by Terson in 1900. In this prospective clinical study the authors examined the actual incidence of Terson hemorrhage in patients suffering aneurysmal SAH, they attempted to identify those parameters that could predispose its development, and they evaluated its prognostic significance in the overall patients' outcome.

Methods

A total of 174 patients suffering aneurysmal SAH were included in this study. The admitting Glasgow Coma Scale scores (GCS), World Federation of Neurological Societies (WFNS) scale scores, Hunt and Hess grades, and Fisher grades were recorded. A careful ophthalmological evaluation was performed in all participants. The exact anatomical locations and the largest diameter of the dome of the ruptured aneurysms were also recorded. Surgical clipping or endovascular coiling was used in 165 patients. Clinical outcome was evaluated at discharge from the hospital by using the Glasgow Outcome Scale and the modified Rankin Scale. Periodic ophthalmological evaluations were performed for 2 years.

Results

In this series, the observed incidence of Terson hemorrhage was 12.1%. Statistical analysis of our data demonstrated that patients with low GCS scores and high WFNS scores, Hunt and Hess grades, and Fisher grades had an increased incidence of Terson hemorrhage. The mortality rate for patients with Terson hemorrhage was 28.6%, whereas that for patients without Terson hemorrhage was 2.0%. Moreover, patients with Terson hemorrhage who survived had significantly worse outcomes than those in patients without Terson hemorrhage.

Conclusions

Terson hemorrhage constitutes a common SAH-associated complication. Its incidence is increased in patients with low GCS and high WFNS scores, and high Hunt and Hess and Fisher grades. Its presence is associated with increased mortality and morbidity rates.

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Theofilos G. Machinis, Kostas N. Fountas, John Hudson, Joe Sam Robinson and E. Christopher Troup

Objective

Ventriculoatrial (VA) shunts remain a valid option for the treatment of hydrocephalus, especially in patients in whom ventriculoperitoneal (VP) shunts fail. Correct positioning of the distal end of the catheter in the right atrium is of paramount importance for maintaining shunt patency and reducing the incidence of VA shunt-associated morbidity. The authors present their experience with real-time transesophageal echocardiography (TEE) monitoring for the accurate placement of the distal catheter of a VA shunt.

Methods

Four patients underwent conversion of a VP shunt to a VA shunt under the guidance of intraoperative fluoroscopy and TEE between May 2003 and December 2004. After induction of general anesthesia, the TEE transducer was advanced into the esophagus. A cervical incision was made and the external jugular vein was visualized. An introducer was passed through an opening in the jugular vein and a guidewire was placed through the introducer. Under continuous TEE guidance, the guidewire was carefully advanced into the superior vena cava. A distal shunt catheter overlying a J-wire was then passed to the superior vena cava, again under TEE guidance. The catheter was advanced to the right atrium after removing the guidewire.

Final visualization with TEE and fluoroscopy revealed a good position of the catheter in the right atrium in all four cases. The mean duration of the operation was 91 minutes (range 65–120 minutes) and the mean operative blood loss was 23 ml (range 10–50 ml). No procedure-related complication was noted.

Conclusions

Real-time TEE is a safe and simple technique for the accurate placement of the distal catheter of a VA shunt.

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Theofilos G. Machinis and Kostas N. Fountas

✓ Herbert Olivecrona was one of the pioneers of modern neurosurgery. In one of his articles, published more than half a century ago, Olivecrona shared his thoughts on the development of neurosurgery in the first half of the twentieth century and his vision regarding the future of neurosurgery and neurosurgical training. In the present paper, the authors communicate their reflections and thoughts on Herbert Olivecrona's visionary article.

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Angel N. Boev, Kostas N. Fountas, Ioannis Karampelas, Christine Boev, Theofilos G. Machinis, Carlos Feltes, Ike Okosun, Vassilios Dimopoulos and Christopher Troup

Object

The authors describe the prospective use of a new hand-held point-and-shoot pupillometer (NeurOptics) to assess pupil function quantitatively.

Methods

Repetitive measurements were made in 90 pediatric participants ranging in age from 1 to 18 years, providing a total of 100 measurements under ambient light conditions. The participants consisted of 45 patients without known intracranial or ophthalmological pathological conditions as well as 45 volunteers in the outpatient setting. Quantitative pupil measurements were reliably replicated in the study participants. The mean resting pupil aperture was 4.11 mm and the minimal diameter after stimulation was 2.65 mm, resulting in a 36% change in pupil size. The mean constriction velocity was 2.34 mm/second, with a mean dilation velocity of 2.2 mm/second.

Conclusion

Pupil symmetry was impressive in the entire cohort.

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Vassilios Dimopoulos, Kostas N. Fountas, Theofilos G. Machinis, Carlos Feltes, Induk Chung, Kim Johnston, Joe Sam Robinson and Arthur Grigorian

Cauda equina syndrome is a well-documented complication of uneventful lumbar microdiscectomy. In the vast majority of cases, no radiological explanation can be obtained. In this paper, the authors report two cases of postoperative cauda equina syndrome in patients undergoing single-level de novo lumbar microdiscectomy in which intraoperative electrophysiological monitoring was used. In both patients, the amplitudes of cortical and subcortical intraoperative somatosensory evoked potentials (SSEPs) abruptly decreased during discectomy and foraminotomy. In the first patient, a slow, partial improvement of SSEPs was observed before the end of the operation, whereas no improvement was observed in the second patient. In the first case, clinical findings consistent with cauda equina syndrome were seen immediately postoperatively, whereas in the second one the symptoms developed within 1.5 hours after the procedure. Postoperative magnetic resonance images obtained in both patients, and a lumbar myelogram obtained in the second one revealed no signs of conus medullaris or nerve root compression. Both patients showed marked improvement after an intense course of rehabilitation. The authors' findings support the proposition that intraoperative SSEP monitoring may be useful in predicting the development of cauda equina syndrome in patients undergoing lumbar microdiscectomy. Nevertheless, further prospective clinical studies are necessary for validation of these findings.

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Theofilos G. Machinis, Kostas N. Fountas, Vassilios Dimopoulos and Joe Sam Robinson

The purpose of this article is to provide insight into the development of surgery for acoustic neurinomas throughout the years. The significant contribution of surgical authorities such as Cushing, Dandy, and House are discussed. The advances in surgical techniques from the very first operations for acoustic tumors at the end of the 19th century until today are described, with special emphasis on the technological and diagnostic milestones that preceded each step of this development.