Theofilos G Machinis

Mercer University, Atlanta, Michigan, United States

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Publications (28)55.1 Total impact

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    ABSTRACT: 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. 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. 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. 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.
    Journal of Neurosurgery 10/2008; 109(3):439-44. DOI:10.3171/JNS/2008/109/9/0439 · 3.74 Impact Factor
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    ABSTRACT: Inflammatory mechanisms have been implicated in the pathogenesis of cerebral vasospasm. C-reactive protein (CRP) represents a sensitive inflammatory marker. The purpose of our current study was to examine the relationship between CRP and the outcomes of patients sustaining aneurysmal subarachnoid haemorrhage (SAH). In a prospective study 24 patients admitted with aneurysmal SAH were included. Serial serum CRP was measured at post-ictal days 0, 1, 3, 6, 9, 12 and 15. Additionally, the admitting Glasgow Coma Scale (GCS) score, Hunt and Hess (HH) grade, Fisher grade, CT scans, angiographic data, transcranial Doppler studies and neurological examination findings were analyzed. All patients were surgically treated within 48 h of their admission. Outcome was assessed by employing the Glasgow Outcome Scale (GOS) and the mean follow-up time was 18 months. Elevated values of CRP upon admission were documented in high grade patients (GCS score <8, HH grade >3). The mean measurement among this group was 14.81 compared to 1.43 of the low-grade group. CRP levels peaked universally on the 3rd post-ictal day. Statistical analysis revealed a positive correlation between increased CRP and poor GOS scores (r=0.73). Our study demonstrated that CRP can serve as a sensitive marker for tissue damage following aneurysmal SAH and could represent a predictive outcome factor.
    Cerebral Vasospasm, 12/2007: pages 377-381;
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    ABSTRACT: The vasodilatory effect of magnesium sulfate (MgSO4) in cerebral vessels has been previously demonstrated. Our prospective, randomized study assessed the effect of MgSO4 in the treatment of vasospasm in patients with spontaneous subarachnoid haemorrhage (SAH). Seventy-four patients with SAH were randomly divided into 3 groups. In Group A, only nimodipine was administered; in Group B, only MgSO4 was given; and in Group C, both nimodipine and MgSO4 were administered. Daily TransCranial Doppler (TCD) measurements of the anterior (ACA) and middle (MCA) cerebral arteries were subsequently obtained. Glasgow Outcome Scale (GOS) scores, hospital stay length, and the cost of treatment were tracked and calculated. Mean flow velocity measurements for ACA and MCA were calculated. Differences between Groups A and B, and Groups A and C (p= 0.0013, 0.0011, respectively) were statistically significant. The mean GOS scores were: Group A, 3.8; Group B, 4.4; and Group C, 4.1. The mean lengths of stay were: Group A, 11.8 ± 0.2 days; Group B, 11.5 ± 0.2 d; and Group C, 11.3 ± 0.1 d. The cost of treatment was similar between all groups. Intravenous MgSO4 significantly decreases cerebral flow velocities. Administration of MgSO4 improved our patients’ outcomes and reduced the length of their hospital stay. Our preliminary results justify the need for a large, randomized multi-institutional study.
    Cerebral Vasospasm, 12/2007: pages 269-273;
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    ABSTRACT: Complications associated with anterior odontoid screw fixation, although not very common can be quite troublesome. We report a patient with early back-out of the implanted screw and its salvage with re-implantation of a longer screw.
    Journal of Clinical Neuroscience 06/2007; 14(5):484-8. DOI:10.1016/j.jocn.2006.02.004 · 1.38 Impact Factor
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    ABSTRACT: Acute cranial subdural hematoma (SDH) represents a common consequence of traumatic brain injury. The vast majority of acute SDHs larger than 10mm in thickness require immediate surgical evacuation. In rare occasions, however, spontaneous resolution may occur. In our current communication, we present four cases of spontaneous resolution of acute cranial SDH. Further more, the proposed theories explaining spontaneous resolution of acute SDH, as well as, clinical parameters and imaging characteristics that might predict such phenomenon, are also reviewed. The possibility of spontaneous resolution of an acute SDH, although remote, may impact the decision making process regarding the management of these patients under certain conditions.
    Clinical Neurology and Neurosurgery 05/2007; 109(3):287-91. DOI:10.1016/j.clineuro.2006.11.005 · 1.13 Impact Factor
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    ABSTRACT: Posterior reversible encephalopathy syndrome (PRES) constitutes a well-described clinical entity, classically entailing characteristic edematous lesions on imaging studies in a patient with altered mental status, visual disturbances, headache, and seizures. PRES is reversible in the vast majority of cases, although progression to ischemia and hemorrhage has been documented. We report a case of a 16-year-old male with chronic renal failure who developed PRES during a hypertensive crisis. The hypertension was successfully managed and PRES-associated symptomatology showed complete regression. However, approximately 2 months later, the patient returned with a spontaneous posterior fossa hemorrhage. Two weeks before this second admission, treatment with low-molecular weight heparin had been initiated. The patient finally succumbed, despite surgical evacuation. The pertinent literature is reviewed. We suggest that the administration of low-molecular weight heparin in the setting of recent PRES might increase the risk for the development of intracranial hemorrhage.
    Child s Nervous System 12/2006; 22(11):1487-91. DOI:10.1007/s00381-006-0155-y · 1.11 Impact Factor
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    ABSTRACT: Golf-related head injuries constitute an increasingly common mechanism of head trauma in children. We present our experience with 33 pediatric cases of golf-associated head injury, with special emphasis in the type of injury, management strategy, and outcome. A thorough review of all children admitted to our hospital with golf-related head injury during a period of 10 years (1 January 1994 to 31 December 2003) was undertaken. The patients' charts, operative reports, imaging studies, and follow-up data were analyzed. A comparison of our findings with those described in the pertinent literature was subsequently performed. Pediatric golf-related head trauma is a significant cause of sport-associated head injury, sometimes harboring a very dismal prognosis. The significance of establishing a task force for the prevention of these injuries cannot be overemphasized.
    Child s Nervous System 11/2006; 22(10):1282-7. DOI:10.1007/s00381-006-0077-8 · 1.11 Impact Factor
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    Theofilos G Machinis · Kostas N Fountas · E Z Kapsalaki · I Kapsalakis · A A Grigorian ·
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    ABSTRACT: The authors report a rare case of complete C2-C3 dislocation with unexpectedly mild neurological symptoms in a 57 year old man involved in a motor vehicle accident, who had previously undergone posterior laminectomy from C3 through C7. A retrospective chart analysis and a thorough radiographic review were performed. X-rays and CT of the cervical spine demonstrated a complete dislocation at the C2-C3 level. Computed tomographic angiography revealed disruption of both vertebral arteries; however, blood flow was evident in the basilar artery. After radiologically guided placement in cervical traction with tongs that reduced the subluxation by approximately 50% the patient had spontaneous eye opening and was able to follow commands. A two-stage 360 degree stabilization and fusion was performed and the patient was finally discharged 24 days after admission with his neurological status essentially unchanged. In conclusion, our patient presented with surprisingly mild neurological symptoms. The previously performed laminectomy could have both predisposed to injury as well as protected his spinal cord from potentially fatal trauma.
    European Spine Journal 11/2006; 15 Suppl 5(Suppl 5):585-9. DOI:10.1007/s00586-005-0019-2 · 2.07 Impact Factor
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    ABSTRACT: 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. 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. Real-time TEE is a safe and simple technique for the accurate placement of the distal catheter of a VA shunt.
    Journal of Neurosurgery 08/2006; 105(1):153-6. DOI:10.3171/jns.2006.105.1.153 · 3.74 Impact Factor
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    ABSTRACT: Intraorbital hydatid disease (IHD) is quite rare and represents < 1% of the Echinococcus cases. In our current communication, we report two children with solitary, primary intraorbital hydatid cysts. Both children presented with nontender, nonpulsatile proptosis. Imaging workup, including CT and MRI scans of the head and the orbits, revealed a retro-bulbar cyst in both patients. Surgical resection was performed by employing a fronto-temporo-orbito-zygomatic (FTOZ) approach. Accidental intraoperative rupture occurred in one case with no further consequences. Albendazole was postoperatively employed for 12 weeks. Outcome was excellent in both cases with complete resolution of their symptoms and complete visual recovery. Pertinent literature was reviewed with this opportunity.
    Southern Medical Journal 07/2006; 99(6):620-4. DOI:10.1097/01.smj.0000217492.03019.16 · 0.93 Impact Factor
  • Kostas N Fountas · Eftychia Z Kapsalaki · Theofilos Machinis · Joe Sam Robinson ·
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    ABSTRACT: In this case report of a screw extrusion into the gastrointestinal tract of a patient 16 months after anterior cervical discectomy and fusion (ACDF), the authors describe a rare but potentially lethal complication and review the literature on this topic. A 70-year-old white man with a surgical history of ACDF at C3-4 underwent an ACDF at C5-6 with autologous bone graft and a dynamic plate using locking, expanding screws. Sixteen months after the operation the patient presented with severe dysphagia. Radiographic findings indicating pulling out of the implanted plate and screws prompted a surgical removal of the instrumentation. One of the screws was not found during the operation and was visualized after surgery by abdominal radiography in the right lower abdominal quadrant. A subsequent Gastrografin swallowing test revealed an esophageal tear. The screw was removed endoscopically and the patient received antibiotics and had no oral intake for 4 days. He was discharged without symptoms on a soft mechanical diet; at 24 weeks, follow-up revealed no changes or symptoms. Screw extrusion into the gastrointestinal tract following ACDF is a rare but potentially lethal complication. The use of locking, expanding screws does not extinguish the risk of this complication, particularly in cases of suboptimal initial placement of the anterior instrumentation. Close follow-up is of paramount importance in detecting any pull-out of the implanted plate. Any signs of postoperative dysphagia or throat soreness should prompt immediate evaluation of the patient and, if indicated, surgical removal of the failed instrumentation.
    Journal of Spinal Disorders & Techniques 06/2006; 19(3):199-203. DOI:10.1097/01.bsd.0000164164.11277.49 · 2.20 Impact Factor
  • Theofilos G Machinis · Kostas N Fountas · Carlos H Feltes · Kim W Johnston · Joe S Robinson ·
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    ABSTRACT: Kyphoplasty, a minimally invasive technique, has recently been developed to provide immediate pain relief, biomechanical stabilization, prevention of fracture progression, vertebral height restoration, and prevention or reversal of kyphosis to patients with osteoporotic vertebral compression fractures (VCF). We retrospectively reviewed 24 patients treated with kyphoplasty. A total of 37 vertebral levels were augmented. Visual analog scale (VAS) scores were documented in the immediate pre- and postoperative period, as well as 4, 12, and 72 weeks after the procedure. Vertebral body height restoration was assessed on postoperative x-rays. Mean preoperative VAS score was 9.3 and improved to 5.4 in the immediate postoperative period. At 4, 12 and 72 weeks post-operatively, mean VAS scores were 5.1, 5.9, and 6.1 respectively. All patients returned to their daily activities within 24 hours. No significant restoration of vertebral body height was observed. In regards to pain relief and postoperative functional outcome, kyphoplasty is a safe and effective treatment modality for osteoporotic VCFs, even when no significant restoration of vertebral body height is achieved.
    Southern Medical Journal 06/2006; 99(5):457-60. DOI:10.1097/01.smj.0000216299.89478.a0 · 0.93 Impact Factor
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    ABSTRACT: Cerebral hydatid cysts account for up to 3.6% of all intracranial space-occupying lesions, in endemic countries. The vast majority of patients affected are children. Computed tomography (CT) and magnetic resonance imaging (MRI) have greatly contributed to a more accurate diagnosis of hydatids. However, correct pre-operative diagnosis still remains quite puzzling. Extirpation of the intact cyst is the treatment of choice, resulting in most cases to a complete recovery. In our retrospective study, we have reviewed 76 cases of intra-cranial hydatid disease operated on in our hospital over a 22 year period. Presenting clinical symptoms and signs and the radiological findings on CT and MRI were documented. Albendazole was given preoperatively to patients with giant (>5 cm) or multiple cysts and postoperatively to all patients. The follow-up period ranged from 12 months to 22 years and the outcome was assessed using the Glasgow Outcome Scale (GOS). Sixty seven (95.7%) of our patients were children. Increased intracranial pressure and papilledema were the predominant findings in this group, whereas focal neurological deficits were most prevalent in adults. CT and MRI revealed round cystic lesions, isodense and iso-intense respectively to cerebrospinal fluid (CSF), with no rim enhancement or perifocal edema. Multiple cysts were identified in 3 cases. Extirpation of the cyst without rupture was accomplished in 56 patients (73.7%). Recurrences occurred in 19 patients (25%). 4 patients (5.3%) died within 6 months after surgery; 3 of these patients had multiple cysts and one died shortly after the operation due to anaphylactic shock following intra-operative rupture of the cyst. Long-term follow-up confirms that intracranial hydatid cysts should always be surgically removed without rupture; the outcome remains excellent in these cases. Correct preoperative diagnosis is vital for the successful outcome of surgery. A high index of suspicion is therefore required in endemic areas despite the availability of advanced neuro-imaging. Medical treatment with albendazole seems to be beneficial both pre- and post-operatively. Newer diagnostic methodologies, such as MR spectroscopy and MR diffusion weighted imaging, might lend themselves to the diagnosis of intracranial hydatid cysts.
    Acta Neurochirurgica 05/2006; 148(4):421-6. DOI:10.1007/s00701-005-0679-z · 1.77 Impact Factor
  • Theofilos G Machinis · Kostas N Fountas ·

    Neurosurgery 04/2006; 58(3):E590; author reply E590. DOI:10.1227/01.NEU.0000207974.15973.EF · 3.62 Impact Factor
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    ABSTRACT: Spinal hydatid disease is a not uncommon cause of spinal cord compression in endemic countries; however, involvement of the epidural space with sparing of the vertebral column is rare. Early diagnosis and surgical decompression with total removal of the hydatid lesion, when possible, is generally considered the standard of care for this disease. The authors describe a case of massive epidural hydatid disease without involvement of the vertebral column in a 62-year-old male patient, treated with a 2-stage surgical operation and administration of systemic albendazole. The literature is reviewed regarding the clinical features, diagnosis, treatment and prognosis of spinal echinococcosis.
    Southern Medical Journal 03/2006; 99(2):178-83. DOI:10.1097/01.smj.0000199747.81684.54 · 0.93 Impact Factor
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    Theofilos G Machinis · Kostas N Fountas ·
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    ABSTRACT: 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.
    Neurosurgical FOCUS 02/2006; 20(5):E10. DOI:10.3171/foc.2006.20.5.11 · 2.11 Impact Factor

  • Neurosurgery 02/2006; DOI:10.1097/00006123-200602000-00071 · 3.62 Impact Factor
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    ABSTRACT: Pupillometry has been widely employed in the evaluation of a large number of pathological conditions, including intracranial pathology. The recent introduction of a portable, user-friendly, infrared pupillometer (ForSite, NeurOptics Inc., Irvine, CA) has enabled the accurate and reproducible measurement of several pupillary parameters, such as maximum and minimum apertures, constriction and dilation velocities, and latency period. It should be noted that various clinical conditions, especially neurological and ocular diseases, as well as numerous medications, may interfere with the measurements. Furthermore, a number of physiological parameters, such as the intensity of retinal illumination, the level of patient's alertness, the intensity of ambient light, as well as the time of day that the examination is performed may alter the obtained values. The potential implications of pupillometry in the clinical assessment of neurosurgical patients, including its complex relationship to intracranial pressure changes, mandate the undertaking of prospective clinical studies validating the clinical significance of this noninvasive, diagnostic modality.
    Neurocritical Care 02/2006; 5(1):55-60. DOI:10.1385/NCC:5:1:55 · 2.44 Impact Factor
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    ABSTRACT: Acute hydrocephalus is a well-documented complication of subarachnoid hemorrhage. The insertion of external ventricular drainage (EVD) has been the standard of care in the management of this complication, aiming primarily at immediate improvement of the clinical condition of these patients, making them more suitable candidates for surgical or endovascular intervention. In our current communication, we review the pertinent literature regarding the relationship of rebleeding and EVD. Several studies have implicated a significantly increased risk of rebleeding in patients with EVD, compared with patients without it. Abrupt lowering of the intracranial pressure could lead to rebleeding due to decreased transmural pressure or removal of the clot sealing the previously ruptured aneurysm. However, a variety of parameters that could affect the rebleeding rate, such as the timing of surgery, the timing and duration of drainage, the size of the aneurysm, as well as the severity of the initial hemorrhage, do not seem to have been adequately explored in the majority of these studies. In addition, a number of clinical trials have failed to provide evidence for the negative role of EVD in the development of rebleeding. Conclusively, further long-term multi-center studies are required in order to establish the exact nature of the relationship between EVD and rebleeding after aneurysmal subarachnoid hemorrhage.
    Neurosurgical Review 02/2006; 29(1):14-8; discussion 19-20. DOI:10.1007/s10143-005-0423-4 · 2.18 Impact Factor
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    ABSTRACT: The authors describe the prospective use of a new hand-held point-and-shoot pupillometer (NeurOptics) to assess pupil function quantitatively. 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. Pupil symmetry was impressive in the entire cohort.
    Journal of Neurosurgery 01/2006; 103(6 Suppl):496-500. DOI:10.3171/ped.2005.103.6.0496 · 3.74 Impact Factor

Publication Stats

355 Citations
55.10 Total Impact Points


  • 2005-2007
    • Mercer University
      • • School of Medicine
      • • Medical Center of Central Georgia
      Atlanta, Michigan, United States
  • 2006
    • Medical Center of Central Georgia
      Macon, Georgia, United States