Biomedical subjects

Azadeh Farin

Publications and source records attributed to Azadeh Farin.

7 recordsLinked to original sources

PubMed2006

Endoscopic third ventriculostomy.

Among patients with idopathic aqueductal stenosis or impedance of cerebrospinal fluid (CSF) flow in the posterior fossa due to tumour, endoscopic fenestration of the floor of the third ventricle creates an alternative route for CSF flow to the subarachnoid space via the prepeduncular cistern. By reestablishing CSF flow, this procedure dissipates any pressure gradient on midline structures. This may obviate the need for traditional CSF shunt diversion techniques in such settings. Currently, endoscopic third ventriculostomy is indicated in approximately 25% of patients with hydrocephalus and can be performed instead of shunt placement. Appropriate patients are those with aqueductal stenosis (10%), obstructive tumours (10%), and obstructive cysts (5%). Additional recent data suggest the favorability of third ventriculostomy over shunt implantation in additional patient cohorts. Operative technique is discussed.

Humans↗

PubMed2006

Transplanted glioma cells migrate and proliferate on host brain vasculature: a dynamic analysis.

Glioma cells have a remarkable capacity to infiltrate the brain and migrate long distances from the tumor, making complete surgical resection impossible. Yet, little is known about how glioma cells interact with the complex microenvironment of the brain. To investigate the patterns and dynamics of glioma cell infiltration and migration, we stereotactically injected eGFP and DsRed-2 labeled rat C6 glioma cells into neonatal rat forebrains and used time-lapse microscopy to observe glioma cell migration and proliferation in slice cultures generated from these brains. In this model, glioma cells extensively infiltrated the brain by migrating along the abluminal surface of blood vessels. Glioma cells intercalated their processes between the endothelial cells and the perivascular astrocyte end feet, but did not invade into the blood vessel lumen. Dynamic analysis revealed notable similarities between the migratory behavior of glioma cells and that previously observed for glial progenitor cells. Glioma cells had a characteristic leading process and migrated in a saltatory fashion, with bursts of migration separated by periods of immobility, and maximum speeds of over 100 microm/h. Migrating glioma cells proliferated en route, pausing for as short as an hour to divide before the daughter cells resumed migrating. Remarkably, the majority of glioma cell divisions took place at or near vascular branch points, suggesting that mitosis is triggered by local environmental cues. This study provides the first dynamic analysis of glioma cell infiltration in living brain tissue and reveals that the migration and proliferation of transplanted glioma cells is directed by interactions with host brain vasculature.

Animals↗

PubMed2005

Intradural cranial congenital dermal sinuses: diagnosis and management.

OBJECTIVE: The congenital dermal sinus (CDS) is a benign tumor-like entity that has unique anatomical and clinical features. We retrospectively examined our data to determine factors associated with adverse outcomes for cranial-based dermal sinuses. METHODS: We retrospectively examined our data obtained from patients presenting between 1975 and 2002. Sixty-seven patients with a CDS were found. Of these, 20 cases of a cranial CDS were identified, 15 of which had evidence of an intradural component. RESULTS: Surgical treatment of congenital dermal sinuses was accompanied with, in general, excellent results. Poor outcomes were most strongly associated with delays in diagnosis. The most common complications were infection at the surgical site (five patients) and hydrocephalus necessitating ventriculoperitoneal shunt placement (two patients). Permanent neurological deficits were rare. CONCLUSION: Cranial CDSs are unusual lesions found in children. A majority of these lesions may penetrate the dura and lead to significant complications if not promptly identified and treated in an appropriate and timely fashion.

Child↗

PubMed2005

Thymoma metastatic to the extradural spine.

BACKGROUND: Spinal epidural metastases are the most common spinal tumor, occurring in 10% of cancer patients. Malignant thymoma is a mediastinal tumor, with extrathoracic metastases occurring in 15% of patients to liver, kidney, and bone. Spinal metastasis is exceptionally rare. We present a case of thymoma with extradural metastasis and discuss the relevant literature. CASE REPORT: We describe a 45-year old man presenting with back pain and hypoesthesia twelve years after a diagnosis of thymoma. A review of the literature reveals few cases of thymoma metastatic to the extradural spine. We describe a novel surgical approach allowing ventral spinal cord decompression through a posterior incision. CONCLUSION: Spinal epidural metastases should be suspected in all cancer patients with back pain. Early detection of epidural metastases may enable improved pain control and preservation of spinal stability, ambulation and sphincter control.

Epidural Neoplasms↗

PubMed2004

Intramedullary spinal cord metastasis of lung adenocarcinoma presenting as Brown-Sequard syndrome.

BACKGROUND: It is extremely rare for cancer to present first as an intramedullary spinal cord metastasis. Furthermore, because it is unlikely for spinal cord neoplasm to present acutely, an acute presentation may signify metastatic disease and should be considered in the initial differential diagnosis. METHODS: The authors present a case of a 59-year-old man presenting with Brown-Sequard syndrome and in whom metastatic lung adenocarcinoma to the spinal cord was subsequently discovered. Review of the literature reveals this case to be one of only a very few where intramedullary tumor was the first manifestation of metastatic disease. RESULTS: The mainstay of treatment for intramedullary spinal metastases remains steroids, radiation, and chemotherapy, though no well-designed study compares these modalities by long-term survival and functional results. This patient underwent local radiation and systemic chemotherapy following surgical resection. CONCLUSIONS: This patient had no preoperative signs suggesting disease in other organs, making the diagnosis of lung adenocarcinoma metastatic to the intramedullary cord surprising, especially given the extremely rare incidence of spinal intramedullary metastatic disease. However, the patient had an acute presentation, uncommon for primary neoplasm, which may be an indication of metastatic disease.

Adenocarcinoma↗

PubMed2003

Sex-related differences in patients with severe head injury: greater susceptibility to brain swelling in female patients 50 years of age and younger.

OBJECT: The goal of this study was to study the influence of sex and age on factors affecting patient outcome in severe head injury. METHODS: Data from the prospectively conducted international trial of tirilazad mesylate in patients with head injury were analyzed retrospectively. Included were 957 patients, 23% of whom were female and all of whom were between the ages of 15 and 79 years. All patients presented with Glasgow Coma Scale (GCS) scores between 3 and 8 and evidence of structural brain damage and/or subarachnoid hemorrhage (SAH) on the initial CT scan. Frequencies of recognized risk factors, including brain swelling, intracranial hypertension, systemic hypotension, advanced age, SAH, and injury severity (based on GCS scores), as well as dichotomized Glasgow Outcome Scale (GOS) scores (good recovery or moderate disability compared with severe disability, persistent vegetative state, or death) obtained 6 months postinjury were compared between male and female patients. CONCLUSIONS: Overall significantly greater frequencies of brain swelling and intracranial hypertension were found in female compared with male patients (35% compared with 24% [p < 0.0008] and 39 compared with 31% [p < 0.03], respectively). The highest rates were found in female patients younger than 51 years old (38% compared with 24% [p < 0.002] and 40% compared with 30% [p < 0.02], respectively, in male patients younger than 51 years of age). This effect was independent of injury severity (GCS) scores, which were not different in male and female patients. Female patients younger than 50 years tended to have worse outcomes, but the difference was not statistically significant. Thus, female patients who sustain severe head injury, especially (presumably) premenopausal ones aged 50 years and younger, are significantly more likely to experience brain swelling and intracranial hypertension than male patients with a comparable injury severity, suggesting that younger women may benefit from more aggressive monitoring and treatment of intracranial hypertension.

Adolescent↗

PubMed2003

Quantitative pupillometry, a new technology: normative data and preliminary observations in patients with acute head injury. Technical note.

The authors prospectively used a new hand-held point-and-shoot pupillometer to assess pupillary function quantitatively. Repetitive measurements were initially made in more than 300 healthy volunteers ranging in age from 1 to 87 years, providing a total of 2,432 paired (alternative right eye, left eye) measurements under varying light conditions. The authors studied 17 patients undergoing a variety of nonintracranial, nonophthalmological, endoscopic, or surgical procedures and 20 seniors in a cardiology clinic to learn more about the effects of a variety of drugs. Additionally, the authors carried out detailed studies in 26 adults with acute severe head injury in whom intracranial pressure (ICP) was continuously monitored. Finally, five patients suffering from subarachnoid hemorrhage were also studied. Quantitative pupillary measurements could be reliably replicated in the study participants. In healthy volunteers the resting pupillary aperture averaged 4.1 mm and the minimal aperture after stimulation was 2.7 mm, resulting in a 34% change in pupil size. Constriction velocity averaged 1.48 +/- 0.33 mm/second. Pupillary symmetry was striking in both healthy volunteers and patients without intracranial or uncorrected visual acuity disorders. In the 2,432 paired measurements in healthy volunteers, constriction velocity was noted to fall below 0.85 mm/second on only 33 occasions and below 0.6 mm/second on eight occasions (< one in 310 observations). In outpatients, the reduction in constriction velocity was observed when either oral or intravenous narcotic agents and diazepam analogs were administered. These effects were transient and always symmetrical. Among the 26 patients with head injuries, eight were found to have elevations of ICP above 20 mm Hg and pupillary dynamics in each of these patients remained normal. In 13 patients with a midline shift greater than 3 mm, elevations of ICP above 20 mm Hg, when present for 15 minutes, were frequently associated with a reduction in constriction velocity on the side of the mass effect to below 0.6 mm/second (51% of 156 paired observations). In five patients with diffuse brain swelling but no midline shift, a reduction in constriction velocities did not generally occur until the ICP exceeded 30 mm Hg. Changes in the percentage of reduction from the resting state following stimulation were always greater than 10%, even in patients receiving large doses of morphine and propofol in whom the ICP was lower than 20 mm Hg. Asymmetry of pupillary size greater than 0.5 mm was observed infrequently (< 1%) in healthy volunteers and was rarely seen in head-injured patients unless the ICP exceeded 20 mm Hg. Pupillometry is a reliable technology capable of providing repetitive data on quantitative pupillary function in states of health and disease.

Adolescent↗