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Uzma Samadani

Publications and source records attributed to Uzma Samadani.

9 recordsLinked to original sources

Stereotactic biopsy of brain stem masses: Decision analysis and literature review.

BACKGROUND: Adult brain stem tumors are rare, and diverse pathology can be found in this location. Stereotactic biopsy of lesions in the brain stem has been performed since the 1960s with high diagnostic and low complication rates. Advances in imaging technology have raised questions regarding the utility of biopsy. We perform decision analysis to aid clinicians in their approach to management of adult brain stem lesions. METHODS: A structured literature search revealed 20 publications with 457 patients who had undergone brain stem lesion biopsy. These publications were reviewed to determine diagnostic rates and the incidence of complications. Standard decision analytic techniques were applied to the case of a virtual adult patient with a lesion in the brain stem. RESULTS: A 1-way sensitivity analysis revealed the likelihood that the preoperative diagnosis was correct and the rate at which incorrect treatment was based on faulty empirical diagnosis as the 2 factors with the greatest effects on patient outcome. The diagnostic rate and complication rate of biopsy, within the ranges reported in the literature, had lesser effects. A threshold analysis was constructed to compare outcomes from stereotactic biopsy vs empiric therapy for a brain stem lesion. The probability that the preoperative diagnosis is correct is plotted vs the probability that empirical treatment based on an incorrect diagnosis will have adverse effect. CONCLUSIONS: Management of lesions in the adult brain stem requires careful consideration of multiple preoperative factors including clinical and radiographic diagnostic certainty, consequences of empiric therapy, and the surgeon's complication rate.

Adult↗

Thalamic deep brain stimulation for posttraumatic action tremor.

We report a case of thalamic deep brain stimulation (DBS) for treatment of posttraumatic tremor. An 18-year-old right-handed man developed a disabling and medically refractory action tremor in the right upper extremity 9 months after sustaining diffuse axonal injury in a motor vehicle collision. DBS of the left ventral intermediate nucleus of the thalamus (Vim) suppressed the tremor without complication and should be considered as an option for the management of intractable posttraumatic tremor.

Adolescent↗

Case studies for illustration and discussion: peripheral nerve tumors.

This article gives a presentation of a variety of surgical cases of peripheral nerve tumors for illustration and discussion. The first three cases include a schwannoma, a neurofibroma, and a desmoid tumor of the brachial plexus region. Case 4 is that of a patient with a common peroneal ganglion cyst, and case 5 is that of a patient with an angiolipoma of the forearm. Cases 6 through 8 illustrate a plexiform neurofibroma, a malignant peripheral nerve sheath tumor, and a metastatic carcinoma to the brachial plexus region. In case 9, a patient with schwannomatosis was treated for multiple spinal schwannomas.

Adult↗

Ulnar nerve entrapment neuropathy at the elbow: simple decompression.

Ulnar nerve entrapment neuropathy at the elbow, or the cubital tunnel syndrome, is frequently encountered in neurosurgical practice as the second most common peripheral nerve entrapment after carpal tunnel syndrome. Patients typically present with weakness or atrophy of the hand as well as paresthesias in the ulnar nerve distribution. The diagnosis can be confirmed with a careful clinical examination and electrophysiological studies. Patients who have failed conservative therapy are considered for surgery. Although a number of surgical options are available, simple decompression of the ulnar nerve can achieve satisfactory results with appropriate patient selection. We describe the relevant anatomy and surgical techniques for simple in situ decompression of the ulnar nerve at the elbow.

Decompression, Surgical↗

Intracranial hypotension after intraoperative lumbar cerebrospinal fluid drainage.

OBJECTIVE: Intraoperative lumbar cerebrospinal fluid drainage is frequently performed in a variety of neurosurgical procedures. A retrospective review is presented of the complications of lumbar cerebrospinal fluid drainage. METHODS: The records from 75 consecutive operations requiring intraoperative lumbar cerebrospinal drainage during a 1-year period at the Hospital of the University of Pennsylvania were reviewed to assess the types of complications attributable to spinal drainage and their rates of occurrence. The operations were categorized into 46 aneurysm clippings, 21 craniotomies for tumors, and 8 other cranial base procedures. RESULTS: Two patients developed transient postoperative neurological complications as a result of intracranial hypotension that resolved after epidural blood patching, with a reexploration craniotomy to drain an epidural collection performed in one patient. A third patient in the study developed a persistent deficit when intracranial hypotension led to intraoperative transtentorial herniation, which resulted in an unusual constellation of multiple brainstem infarcts that caused cranial neuropathy. CONCLUSION: Complications of intraoperative lumbar cerebrospinal fluid drainage resulting in transient (2 of 75 patients, 3%) or persistent (1 of 75 patients, 1%) neurological deficits caused by intracranial hypotension occur infrequently and may be related to preexisting conditions such as hydrocephalus.

Adult↗

Stereotactic brainstem biopsy is indicated for the diagnosis of a vast array of brainstem pathology.

BACKGROUND/AIMS: A meta-analysis of thirteen studies performing stereotactic biopsy of brainstem lesions is combined with our recent series of 12 patients with brainstem lesions comparing MRI findings to biopsy histopathology to determine whether these lesions could have been diagnosed radiographically. METHODS: 12 consecutive stereotactic biopsies and literature analysis were performed to analyze clinical, radiographic and histopathologic data. RESULTS: Stereotactic biopsy of lesions in the brainstem was in 96% diagnostic. There was one mortality (3% of cases) and 4% morbidity associated with the procedure. Pathology showed that half of the adult brainstem intrinsic lesions were gliomas, 10% were metastases, and the remainder were hematomas, vascular malformations, lymphomas, demyelination, cysts, radiation necrosis, abscesses, vasculitis, infarcts, leukemia, cryptococcus, or granulomas. CONCLUSIONS: Empiric treatment of adult brainstem lesions is not prudent because there is a wide spectrum of diverse pathology in this location. Stereotactic biopsy is a safe and effective method for determining histopathology.

Adult↗

Ventriculosagittal sinus shunt placement: technical case report.

OBJECTIVE AND IMPORTANCE: Determining an appropriate site for distal catheter placement for ventricular shunting for some hydrocephalic patients can be difficult. We describe a simplification of the technique for sagittal sinus shunt placement using a guidewire. CLINICAL PRESENTATION: A 20-month-old infant with hydrocephalus secondary to Alexander's disease developed erosion of her parieto-occipital ventriculoperitoneal shunt reservoir through an occipital decubitus scalp ulceration. Her hydrocephalus was temporarily treated with a ventriculostomy; however, she developed pneumatosis intestinalis while in the hospital. TECHNIQUE: The patient underwent placement of a ventriculosagittal sinus shunt. The ventricular catheter and shunt valve were placed through a burr hole at Kocher's point, and the distal end of the catheter was placed in the superior sagittal sinus by using the Seldinger technique. CONCLUSION: Ventriculosagittal sinus shunting may be used as an alternative to traditional methods for patients for whom distal shunt placement is problematic. Our technique has the theoretical advantage of reducing the risks of blood loss or air embolism by not requiring a scalpel incision into the sinus.

Cerebral Ventricles↗

Thalamic deep brain stimulation for disabling tremor after excision of a midbrain cavernous angioma. Case report.

Thalamic deep brain stimulation (DBS) has been demonstrated to be effective for the treatment of parkinsonian or essential tremor. To date, however, few data exist to support the application of this method to treat midbrain tremor. A 24-year-old right-handed man underwent radiosurgery and subsequent resection of a recurrently hemorrhaging cavernous angioma located in the left side of the midbrain. The surgery exacerbated severe choreoathetotic resting and action tremors of his right extremities and trunk. The patient underwent placement of a deep brain stimulator into the left ventral intermediate nucleus of the thalamus (Vim). Postoperatively, decreased truncal ataxia and right-sided choreoathetotic tremor were demonstrated, with a 57% increase in dexterity as measured by task testing. The authors demonstrate that DBS can be an effective treatment modality for disabling tremor after resection of a midbrain cavernous angioma.

Adult↗