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Dive into the research topics where Tony Rizk is active.

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Featured researches published by Tony Rizk.


Childs Nervous System | 1992

Recurrent intrinsic brain stem epidermoid cyst

Dominique Fournier; Philippe Mercier; Philippe Menei; François Pouplard; Tony Rizk; Gilles Guy

The authors report the case of a 14-month-old baby boy with an epidermoid cyst located entirely within the pons and medulla, without an exophytic component. The lesion was examined by computed tomography and magnetic resonance imaging. The child was operated upon three times after two recurrences of the lesion. A suboccipital, subtonsillar approach was used for the first and second procedures and a transtemporal approach for the last one. Excision was thought to be complete the first time, since a solid tumor was found and removed in a large cyst. The cyst wall was not identified. No tumor was found during the second procedure despite recurrence of the cyst, which was drained without an attempt to remove the cyst wall. Finally the cyst recurred with a large tumor in the cyst wall which was again totally removed. Consistent with the high mortality of brain stem epidermoid cysts in the literature, the child eventually died. The therapeutic problems, surgical options, and consequences are discussed.


Clinical Neurology and Neurosurgery | 2008

Impact of the lunar cycle on the incidence of intracranial aneurysm rupture: Myth or reality?

Youssef Ali; Ralph Rahme; Nayla Matar; Ibrahim Ibrahim; Lina Menassa-Moussa; J. Maarrawi; Tony Rizk; G. Nohra; N. Okais; Elie Samaha; Ronald Moussa

OBJECTIVE To analyze the impact of the lunar cycle and season on the incidence of aneurysmal subarachnoid hemorrhage (SAH). PATIENTS AND METHODS The medical records of 111 patients who were admitted over a 5-year period to our department because of aneurysmal SAH were retrospectively reviewed. The date of aneurysm rupture was matched with the corresponding season and moon phase. RESULTS An incidence peak for aneurysm rupture (28 patients) was seen during the phase of new moon, which was statistically significant (p < 0.001). In contrast, no seasonal variation in the incidence of SAH was observed. CONCLUSION The lunar cycle seems to affect the incidence of intracranial aneurysm rupture, with the new moon being associated with an increased risk of aneurysmal SAH.


Neurosurgery | 1994

Are the calcium antagonists really useful in cerebral aneurysmal surgery? A retrospective study.

Philippe Mercier; Ghassan Alhayek; Tony Rizk; Dominique Fournier; Philippe Menei; Gilles Guy

From 1983 to 1990, 234 patients with one or several cerebral arterial aneurysms were surgically treated in our department. Since 1983, we have been performing surgery as early as possible. As soon as the subarachnoid hemorrhage diagnosis is confirmed by computed tomography (or if unconfirmed, by lumbar puncture), we assume that each patient may have an aneurysm. Between 1987 and 1990, 111 patients were treated by vascular volume expansion (maintenance of central venous pressure above 5 cm H2O with 4% albumin or Ringer-lactate or, if necessary, with 20% albumin), which we supplemented with calcium antagonists (nimodipine in 60 patients and nicardipine in 51 patients). Two months after being discharged, each patient is examined by a neurosurgeon and, on the same day, is subjected to a neuropsychological evaluation and a computed tomographic scan of the brain. A few months after this consultation, a working-position/family-activities questionnaire is issued to the patient. All of the results studied on the basis of postoperative mortality, second-month computed tomographic scan ischemia, neuropsychological evaluation, and return to work show no significant difference between the groups with or without calcium antagonists or between the nimodipine and nicardipine subgroups.


Journal of Neurosurgery | 2010

What happens to Modic changes following lumbar discectomy? Analysis of a cohort of 41 patients with a 3- to 5-year follow-up period

Ralph Rahme; Ronald Moussa; Rabih Bou-Nassif; Joseph Maarrawi; Tony Rizk; G. Nohra; Elie Samaha; N. Okais

OBJECT The natural history of Modic changes (MCs) in the lumbar spine is often marked by conversion from one type to another, but their course following lumbar discectomy remains unknown. The authors sought to study the impact of surgery on the natural history of these lesions. METHODS Forty-one patients treated with lumbar microdiscectomy between 2004 and 2005 were enrolled in this study and underwent clinical evaluation and repeat MR imaging after a median follow-up of 41 months (range 32-59 months). Preoperative and follow-up MR images were reviewed and the type, location, and extent of MCs at the operated level were recorded and compared. RESULTS The study population consisted of 27 men and 14 women with a mean age of 54 years (range 24-78 years). During the follow-up period, the prevalence of MCs increased from 46.3% to 78%, and 26 patients (63.4%) had Type 2 lesions at the operated level. Of the 22 patients without MCs, 4 (18.2%) converted to Type 1 and 9 (40.9%) to Type 2. Of the 5 Type 1 lesions, 3 (60%) converted to Type 2, and 2 (40%) remained Type 1 but increased in size. In contrast, none of the 14 Type 2 changes converted to another type, although 10 (71.4%) increased in extent. There were no reverse conversions to Type 0. CONCLUSIONS Following lumbar discectomy, most patients develop Type 2 changes at the operated level, possibly as a result of accelerated degeneration in the operated disc. Neither the preoperative presence of MCs nor their postoperative course appears to affect the clinical outcome.


Childs Nervous System | 2000

Congenital brain tumor in a neonate conceived by in vitro fertilization

Tony Rizk; Rima Nabbout; Salam Koussa; Carlo Akatcherian

Abstract Congenital brain tumors are very rare; their incidence is estimated at 0.34 per million live births. We report a case of congenital gliosarcoma in a neonate conceived by in vitro fertilization (IVF). One other case of brain tumor (medulloblastoma) is reported in a child born after assisted conception. Whether these tumors are causally related to the IVF remains obscure.


Pediatric Neurosurgery | 2002

Schwannoma of the Tentorium Cerebelli in a Child

Pascal Jabbour; Tony Rizk; Georges Abi Lahoud; Roula Hourani; Antoine Checrallah; Elie Samaha; G. Nohra; Ronald Moussa; N. Okais

Intracranial schwannomas not arising from a cranial nerve are very rare. Schwannomas of the dura are even rarer; in the literature, we found only two cases: a schwannoma of the falx and one of the torcula. We report a third case of a 9-year-old girl with a schwannoma of the tentorium cerebelli. The different theories concerning the origin of this tumor in this particular location are discussed.


Neurochirurgie | 2004

Neurocytome central: À propos de quatre cas

Ronald Moussa; G. Abadjian; M. Nader; Tony Rizk; Elie Samaha; G. Nohra; A. Checrallah; N. Okais

Resume Nous rapportons 4 cas de neurocytomes traites a l’Hotel-dieu de France a Beyrouth entre 1994 et 2002. Il s’agit d’une tumeur ventriculaire benigne du sujet jeune a differenciation neuronale. Elle se revele le plus souvent par un tableau d’hypertension intracrânienne. Le diagnostic histologique peut parfois se montrer difficile, necessitant le recours aux techniques d’immunomarquage. Le traitement de choix est la resection chirurgicale complete. Le pronostic est le plus souvent excellent (cas n° 1 et 2). Toutefois, meme apres une exerese totale, certaines tumeurs peuvent recidiver (cas n° 3). Dans de rares cas (cas n° 4), cette tumeur peut avoir un comportement agressif, necessitant le recours a des traitements complementaires. La prise en charge des recidives ou des residus sera discutee.


Pediatric Neurosurgery | 2009

Endoscopic Third Ventriculostomy: The Lebanese Experience

Ralph Rahme; Rudy J. Rahme; Roula Hourani; Ronald Moussa; G. Nohra; N. Okais; Elie Samaha; Tony Rizk

Background: Endoscopic third ventriculostomy (ETV) has gained wide popularity as a first-line treatment for obstructive hydrocephalus (OHC). We have been performing ETV since 1998. We report our experience with this technique in the management of OHC. Methods: Between 1998 and 2007, we performed 49 ETV procedures in 46 patients suffering from OHC. Medical records were retrospectively reviewed. Success was defined as shunt-free survival. Results: There were 29 males and 17 females with a mean age of 23 years (6 months–65 years). Aqueductal stenosis and tectal tumor were the most common etiologies (63%). Seven patients (15.6%) had early ETV failure. Of 38 patients with initial success and available follow-up, shunt independence was achieved in 29 patients (76.3%) after a mean follow-up of 37 months. Kaplan-Meier analysis yielded a 70% 5-year shunt-free survival rate. On multivariate analysis, no variables could predict early or late ETV failure. Transient complications occurred in 6 patients (13%), but there were no ETV-related deaths or permanent morbidity. Conclusion: ETV is a safe and effective treatment for OHC, resulting in a high rate of long-term shunt independence with a low risk of complications. ETV should be considered the treatment of choice for patients with OHC and its development as a substitute to shunt placement should be encouraged in neurosurgically developing countries.


Journal of Neurosurgery | 2013

Solitary fibrous tumor of the scalp in a child.

Tony Rizk; Adnan Awada; Amer Sebaaly; Roula Hourani

Solitary fibrous tumors (SFTs) are rare mesenchymal neoplasms that arise most commonly in the pleura but have been increasingly reported in extrapleural sites. The authors report the case of an SFT of the scalp that manifested as an enlarging scalp mass in a 2-year-old boy. The mass was surgically excised. Histological examination showed it to be composed of fusiform cells of variable cellularity with a central hyalinization zone. Immunohistochemical staining was positive for CD34 and negative for smooth muscle actin, S100 protein, desmin, and h-caldesmon. On 1-year follow-up, there was no recurrence of the mass. This case presented some diagnostic difficulty because of the wide range of possible diagnoses for a pediatric scalp mass; however, the distinct immunohistochemical profile helped to eliminate other more frequent fibrous tumors of the scalp. The behavior of scalp SFTs is usually benign, but their course can be unpredictable, and recognition of these lesions is essential.


Canadian Journal of Neurological Sciences | 2011

Lumbar microdiscectomy: a clinicoradiological analysis of outcome.

Ralph Rahme; Ronald Moussa; Rabih Bou-Nassif; Joseph Maarrawi; Tony Rizk; G. Nohra; Elie Samaha; N. Okais

BACKGROUND The long-term outcome after lumbar microdiscectomy (LMD) may be affected by low back pain (LBP) and segmental instability, the determinants of which remain unclear. We sought to analyze the interaction between clinical, functional, and radiological variables and their impact on patient outcome. METHODS All patients who underwent LMD in 2004-2005 were invited to participate in this retrospective cohort study. Patients were re-evaluated clinically and radiologically after a three to five year follow-up. RESULTS Forty-one of 97 eligible patients were enrolled. Twelve patients (29.3%) reported moderate-to-severe sciatica, 12 (29.3%) had moderate LBP, and 13 (31.7%) exhibited clinical evidence of segmental instability. Thirty-eight patients (92.7%) had minimal disability and 3 (7.3%) had moderate disability. Twenty-three patients (56.1%) were fully satisfied, while 18 (43.9%) had only partial satisfaction, having expected a better outcome. Thirty-three patients (80.5%) returned to full-time work. Median disc space collapse (DSC) was 20% (range 5-66%) and L4-L5 was particularly affected. Prevalence of Modic changes increased from 46.3% to 78% with type 2 predominance. Multivariate logistic regression analysis identified the following negative prognostic factors: female sex, young age, lack of regular exercise, and chronic preoperative LBP. There was no correlation between the course of Modic changes, DSC, and patient outcome. CONCLUSION Although many patients may be symptomatic following LMD, significant disability and dissatisfaction are uncommon. Female sex, young age, lack of exercise, and chronic preoperative LBP may predict a worse outcome. Disc collapse is a universal finding, particularly at L4-L5. Neither DSC nor Modic changes seem to affect patient outcome.

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N. Okais

Saint Joseph's University

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G. Nohra

Saint Joseph's University

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Elie Samaha

Saint Joseph's University

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Ronald Moussa

Saint Joseph's University

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Ralph Rahme

Saint Joseph's University

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Pascal Jabbour

Thomas Jefferson University

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J. Maarrawi

Saint Joseph's University

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Roula Hourani

American University of Beirut

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Salam Koussa

Saint Joseph's University

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