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1.
AIDS Behav ; 27(12): 3970-3980, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37318665

ABSTRACT

We assessed the prevalence and correlates of alcohol use among 870 people who inject drugs living with HIV in Kenya, with attention toward (1) sexual and injecting risk behaviors for HIV transmission and (2) HIV care engagement. We defined heavy alcohol use as > 14 drinks/week for men and > 7 drinks/week for women, moderate alcohol use as any lesser but non-zero amount, and any alcohol use as either moderate or heavy use. Approximately 39% of participants reported any alcohol use and 15% heavy use. In multivariate analysis, any alcohol use compared to no use was associated with needle sharing, > 3 new sex partners in the past 3 months, being unaware of HIV status, never enrolling in HIV care, and not being on ART (all p < 0.05). Heavy alcohol use as compared to no use was associated with needle sharing (aOR = 2.72; 95% CI 1.43, 5.13), injection equipment sharing (aOR = 1.80; 95% CI 1.00, 3.16), > 3 new sex partners in the past 3 months (aOR = 1.99; 95% CI 1.12, 3.49), and being unaware of HIV status (aOR = 2.77; 95% CI 1.46, 5.19). There was no association between any measure of alcohol use and unsuppressed viral load. Alcohol use among people who inject drugs living with HIV may carry elevated risk of HIV transmission mediated by sexual and injecting practices and is associated with lower engagement in multiple stages of the HIV care cascade.

2.
AJNR Am J Neuroradiol ; 44(2): 157-164, 2023 02.
Article in English | MEDLINE | ID: mdl-36702499

ABSTRACT

BACKGROUND AND PURPOSE: Given the increased use of stereotactic radiosurgical thalamotomy and other ablative therapies for tremor, new biomarkers are needed to improve outcomes. Using resting-state fMRI and MR tractography, we hypothesized that a "connectome fingerprint" can predict tremor outcomes and potentially serve as a targeting biomarker for stereotactic radiosurgical thalamotomy. MATERIALS AND METHODS: We evaluated 27 patients who underwent unilateral stereotactic radiosurgical thalamotomy for essential tremor or tremor-predominant Parkinson disease. Percentage postoperative improvement in the contralateral limb Fahn-Tolosa-Marin Clinical Tremor Rating Scale (TRS) was the primary end point. Connectome-style resting-state fMRI and MR tractography were performed before stereotactic radiosurgery. Using the final lesion volume as a seed, "connectivity fingerprints" representing ideal connectivity maps were generated as whole-brain R-maps using a voxelwise nonparametric Spearman correlation. A leave-one-out cross-validation was performed using the generated R-maps. RESULTS: The mean improvement in the contralateral tremor score was 55.1% (SD, 38.9%) at a mean follow-up of 10.0 (SD, 5.0) months. Structural connectivity correlated with contralateral TRS improvement (r = 0.52; P = .006) and explained 27.0% of the variance in outcome. Functional connectivity correlated with contralateral TRS improvement (r = 0.50; P = .008) and explained 25.0% of the variance in outcome. Nodes most correlated with tremor improvement corresponded to areas of known network dysfunction in tremor, including the cerebello-thalamo-cortical pathway and the primary and extrastriate visual cortices. CONCLUSIONS: Stereotactic radiosurgical targets with a distinct connectivity profile predict improvement in tremor after treatment. Such connectomic fingerprints show promise for developing patient-specific biomarkers to guide therapy with stereotactic radiosurgical thalamotomy.


Subject(s)
Connectome , Essential Tremor , Radiosurgery , Humans , Tremor/diagnostic imaging , Tremor/surgery , Treatment Outcome , Thalamus/diagnostic imaging , Thalamus/surgery , Magnetic Resonance Imaging , Essential Tremor/surgery
3.
BJOG ; 129(6): 926-937, 2022 May.
Article in English | MEDLINE | ID: mdl-34839583

ABSTRACT

OBJECTIVE: To determine the contribution of specific contraceptive side effects to method switch and modern-method discontinuation among Kenyan women. DESIGN: A prospective cohort study. SETTING: Five counties in Western Kenya. PARTICIPANTS: Women aged ≥18 years old and emancipated female minors ≥14 years old using modern, reversible contraception were recruited while attending 10 public health facilities. METHODS: Patient-reported adverse effect symptoms, method switch and discontinuation were reported through weekly text message-based surveys for 24 weeks. MAIN OUTCOME MEASUREMENTS: Prevalence, hazards ratio (HR). RESULTS: Among 825 women, 44% were using implants, 43% injectables, 7% an intrauterine device and 6% oral contraceptive pills at enrolment. Most (61%) women were continuing a method used in the previous month. During the 24-week follow up, incidence of contraceptive switch was 61.3 per 100 person-years (95% confidence interval [CI] 52.4-71.8) and incidence of discontinuation was 38.5 per 100 person-years (95% CI 31.6-47.0). On average, one-quarter (prevalence [Pr] 0.24, 95% CI 0.22-0.26) of participants reported side effects or method problems weekly, with sexual side effects the most prevalent symptom (Pr 0.15, 95% CI 0.13-0.16). Lack of expected bleeding was associated with higher risk of method switch (adjusted hazard ratio [aHR] 2.36, 95% CI 1.22-4.57). Risk of all-modern method discontinuation was higher among women experiencing irregular bleeding (aHR 2.39, 95% CI 1.20-4.77), weight changes (aHR 2.72, 95% CI 1.47-4.68) and sexual side effects (aHR 2.42, 95% CI 1.40-4.20). CONCLUSIONS: Addressing irregular bleeding, weight changes and sexual side effects through development of new products that minimise these specific side effects and anticipatory counseling may reduce method-related discontinuation. TWEETABLE ABSTRACT: Bleeding, weight changes, sexual problems associated with discontinuation of #contraception, but many continue despite side effects.


Subject(s)
Contraception Behavior , Contraception , Adolescent , Adult , Contraception/adverse effects , Contraception/methods , Contraceptives, Oral, Combined , Female , Humans , Kenya/epidemiology , Male , Prospective Studies
4.
J Clin Neurosci ; 70: 102-107, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31447361

ABSTRACT

OBJECTIVES: Repeat Gamma Knife stereotactic radiosurgery (GKSR) for refractory trigeminal neuralgia (TGN) is an increasingly common practice. Prior studies have reported varying success rates and incidence of trigeminal nerve dysfunction following repeated GKSR. We report treatment outcomes and toxicity in patients following repeat GKSR for TGN at the University of Alabama at Birmingham (UAB) with a focused review of the literature. METHODS: We retrospectively reviewed medical records of 55 TGN patients re-treated with radiosurgery using the Leksell Gamma Knife® at the University of Alabama at Birmingham between 1996 and 2012. Outcomes were defined using the Modified Marseille Scale. Demographics, prior treatments and symptom duration were correlated with outcomes. RESULTS: Eighteen patients (33%) achieved Marseille Class I or II, 14 (25%) Class III or IV, and 23 (42%) Class V at a mean follow-up of 14.4 months. Twenty-five patients (45%) developed new trigeminal nerve dysfunction after re-treatment. Of these, four (16%) did not develop dysfunction until subsequent microvascular decompression (MVD) for inadequate symptom relief. CONCLUSIONS: Although more than half of the patients undergoing repeat GKSR for refractory TGN maintained excellent or good outcomes (Marseille classes I-IV) at an average follow-up of 14.4 months, neither age, gender, nor pre-treatment duration of symptoms or interval between treatments had a statistically significant effect on outcomes. Following repeat GKSR, patients have increased risk for new-onset trigeminal nerve dysfunction and those undergoing MVD after repeat GKSR may have an increased risk for new-onset trigeminal nerve dysfunction.


Subject(s)
Postoperative Complications , Radiosurgery/adverse effects , Radiosurgery/methods , Reoperation/adverse effects , Trigeminal Neuralgia/surgery , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Postoperative Complications/epidemiology , Postoperative Complications/etiology , Reoperation/methods , Treatment Outcome
5.
Lipids Health Dis ; 16(1): 110, 2017 Jun 09.
Article in English | MEDLINE | ID: mdl-28599673

ABSTRACT

BACKGROUND: Antiretroviral treatment (ART) is associated with dyslipidemia yet little is known about the burden of dyslipidemia in the absence of ART in sub-Saharan Africa. We compared the prevalence and risk factors for dyslipidemia among HIV-infected ART-naïve adults and their uninfected partners in Nairobi, Kenya. METHODS: Non-fasting total cholesterol (TC) and high density lipoprotein cholesterol (HDL) levels were measured by standard lipid spectrophotometry on thawed plasma samples obtained from HIV-infected participants and their uninfected partners. Dyslipidemia, defined by high TC (>200 mg/dl) or low HDL (<40 mg/dl) was compared between HIV-infected and uninfected men and women. RESULTS: Among 196 participants, median age was 32 years [IQR: 23-41]. Median CD4 count among the HIV-infected was 393 cells/ µl (IQR: 57-729) and 90% had a viral load >1000 copies/ml. Mean TC and HDL were comparable for HIV-infected and uninfected participants. Prevalence of dyslipidemia was 83.8% vs 78.4% (p = 0.27). Among the HIV-infected, those with a viral load >1000 copies/ml were 1.5-fold more likely to have dyslipidemia compared to those with ≤1000 copies/ml (adjusted prevalence ratio [aPR] 1.5, 95% CI: 1.22-30.99, p = 0.02). BMI, age, gender, blood pressure and smoking were not significantly associated with dyslipidemia. CONCLUSIONS: Among ART-naïve HIV-infected adults, high viral load and low CD4 cell count were independent predictors of dyslipidemia, underscoring the importance of early initiation of ART for viral suppression.


Subject(s)
Cholesterol, HDL/blood , HIV Infections/blood , HIV Infections/genetics , Lipids/blood , Adult , Antiretroviral Therapy, Highly Active , Cholesterol, HDL/genetics , Female , HIV Infections/therapy , HIV Infections/virology , HIV-1/genetics , HIV-1/pathogenicity , Humans , Kenya , Male , Risk Factors , Viral Load/genetics
6.
Ann Allergy Asthma Immunol ; 87(5): 390-3, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11730181

ABSTRACT

BACKGROUND: The Rotorod Sampler (Sampling Technologies, St. Louis Park, MN) is a rotating-arm impactor that recovers airborne particles on two rapidly moving plastic collector rods. For decades, the standard method for applying silicone grease to collector rods has been with one's finger. Although this method can yield excellent results when performed by practiced investigators, a relatively high skill level is required, and significant intrapreparer variability has been reported in the medical and technical literature. OBJECTIVE: The purpose of this investigation was to develop and evaluate a new method for coating Rotorod collector rods with silicone grease. METHODS: Collector rods were coated with silicone grease by dipping them into a solution consisting of silicone grease and hexane. Pollen recovery by these dipped collector rods was compared with pollen counts obtained with hand-greased collector rods. RESULTS: Twenty-three paired samples were obtained during five sampling periods. Pollen recovery by the hand-greased and dipped collector rods was similar (P = 0.410). Dipped collector rods generally offered a lower standard deviation than hand-greased collector rods, however, differences were not statistically significant (F = 1.782, P = 0.087). Dipped collector rods were also superior to hand-greased collector rods in several qualitative categories such as grease uniformity, time required for microscopic analysis, and visual quality. CONCLUSIONS: Dipped collector rods offered a time-efficient means to obtain atmospheric samples with excellent visual quality. The resulting pollen counts were similar to data obtained via the standard, manual method. Allergists are encouraged to consider using this new method in their office practices and for drug studies.


Subject(s)
Air Pollution/analysis , Allergens/analysis , Environmental Monitoring/methods , Pollen , Silicones/chemistry , Kinetics , Reference Standards , Reproducibility of Results
7.
J Digit Imaging ; 14(2 Suppl 1): 140-2, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11442075

ABSTRACT

Clinician efficiency can be enhanced by worklists that compile useful data for rapid access at the time of need. The authors report development of a web-based, user-edited "Patient List Manager" for the Clinical Image Management System (CIMS). The CIMS List Manager interfaces with the CIMS Archive to provide the user with available studies. It has tools that let the user build personal lists from the available studies. Listed studies are moved from the archive to the cache for rapid access at the time of need. Users can build/edit the list through a browser (without viewing pictures) or from within the image viewer. In this way, the List Manager distributes list building into knowledgeable hands. This is particularly valuable at the current time when health system patient registries are not mature enough to reliably support building build anticipatory patient lists.


Subject(s)
Internet , Medical Records Systems, Computerized , Radiology Information Systems , Humans
8.
J Digit Imaging ; 14(2 Suppl 1): 190-3, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11442092

ABSTRACT

The authors investigated clinician transactions against the Digital Imaging and Communications in Medicine (DICOM) archive within a clinical image management system (CIMS) in support of patient care. A Neurosurgical Oncology practice was audited for image utilization. There were 400 requests for 233 image studies during 297 sessions. Fifty percent were for current studies, and 50% were for historical studies. Current studies alone were requested in 37% of the sessions, current plus historical in 31%, and historical alone in 32% of the sessions. Seventy percent of studies were within 8 weeks old and were rapidly available from the CIMS disk cache without an archive image transaction. Conversely, 30% were older than 8 weeks, requiring a clinician transaction against the archive for image retrieval. Approximately 25% of studies were older than 3 months and 10% older than 6 months. Clinician image needs are complex and any CIMS solution must include a DICOM archive that can support clinician-based transactions.


Subject(s)
Radiology Information Systems , Database Management Systems , Humans , Neurosurgery
9.
J Neurophysiol ; 82(2): 551-63, 1999 Aug.
Article in English | MEDLINE | ID: mdl-10444655

ABSTRACT

Drift of the eyes after saccades produces motion of images on the retina (retinal slip) that degrades visual acuity. In this study, we examined the contributions of proprioceptive and retinal afference to the suppression of postsaccadic drift induced by a unilateral ocular muscle paresis. Eye movements were recorded in three rhesus monkeys with a unilateral weakness of one vertical extraocular muscle before and after proprioceptive deafferentation of the paretic eye. Postsaccadic drift was examined in four visual states: monocular viewing with the normal eye (4-wk period); binocular viewing (2-wk period); binocular viewing with a disparity-reducing prism (2-wk period); and monocular viewing with the paretic eye (2-wk period). The muscle paresis produced vertical postsaccadic drift in the paretic eye, and this drift was suppressed in the binocular viewing condition even when the animals could not fuse. When the animals viewed binocularly with a disparity-reducing prism, the drift in the paretic eye was suppressed in two monkeys (with superior oblique pareses) but generally was enhanced in one animal (with a tenotomy of the inferior rectus). When drift movements were enhanced, they reduced the retinal disparity that was present at the end of the saccade. In the paretic-eye-viewing condition, postsaccadic drift was suppressed in the paretic eye and was induced in the normal eye. After deafferentation in the normal-eye-viewing state, there was a change in the vertical postsaccadic drift of the paretic eye. This change in drift was idiosyncratic and variably affected the amplitude and velocity of the postsaccadic drift movements of the paretic eye. Deafferentation of the paretic eye did not affect the postsaccadic drift of the normal eye nor did it impair visually mediated adaptation of postsaccadic drift. The results demonstrate several new findings concerning the roles of visual and proprioceptive afference in the control of postsaccadic drift: disconjugate adaptation of postsaccadic drift does not require binocular fusion; slow, postsaccadic drift movements that reduce retinal disparity but concurrently increase retinal slip can be induced in the binocular viewing state; postsaccadic drift is modified by proprioception from the extraocular muscles, but these modifications do not serve to minimize retinal slip or to correct errors in saccade amplitude; and visually mediated adaptation of postsaccadic drift does not require proprioceptive afference from the paretic eye.


Subject(s)
Afferent Pathways/physiology , Ophthalmoplegia/physiopathology , Proprioception/physiology , Retina/physiology , Saccades/physiology , Adaptation, Physiological , Animals , Denervation , Macaca mulatta
10.
Article in English | MEDLINE | ID: mdl-9742279

ABSTRACT

Cholesterol granulomas of the temporal bone without clinical symptoms of chronic otitis media may result from an indolent inflammatory process caused by a congenitally blocked group of air cells. A unique case of giant bilateral cholesterol granulomas of the temporal bone is presented to support this theory. Management allowed bilateral surgical removal with hearing preservation. The differentiation between cholesterol granuloma, giant cholesterol cyst and other lesions of the temporal bone is discussed. The presumed pathogenesis of this condition is reviewed.


Subject(s)
Bone Diseases/diagnosis , Cholesterol , Granuloma, Foreign-Body/diagnosis , Temporal Bone/pathology , Bone Diseases/complications , Bone Diseases/surgery , Granuloma, Foreign-Body/complications , Granuloma, Foreign-Body/surgery , Headache/etiology , Hearing Loss, Sensorineural/etiology , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Temporal Bone/surgery , Vertigo/etiology
11.
J Neurooncol ; 36(2): 191-8, 1998 Jan.
Article in English | MEDLINE | ID: mdl-9525819

ABSTRACT

PURPOSE: To assess the response of patients with recurrent malignant gliomas to intra-arterial (IA) cisplatin. METHODS: Eligibility criteria included patients with recurrent supratentorial malignant gliomas and measurable, unilateral contrast-enhancing tumor located within the territory of one or two major cerebral arteries. Patients received 75 mg/m2 IA cisplatin every four weeks. Depending on individual patients' tumor topography, cisplatin was infused either into the cervical internal carotid artery (ICA) (15 patients), or into one or two major cerebral arteries (26 patients), most often the M1 segment of the middle cerebral artery. RESULTS: Of 40 patients evaluable for tumor response, four patients (10%) were responders and nine patients (22%) had disease stabilization. The median time to tumor progression among the 13 patients with tumor response or stable disease was 23.7 weeks. The response rate did not significantly differ between patients receiving ICA versus selective intracerebral infusion, although the latter group contained a higher proportion of glioblastoma. Tumor progression occurred solely as local failure in 33 patients (82%), with all enhancing tumor still located within the vascular territory infused with IA cisplatin. Ipsilateral vision loss occurred in two patients after ICA cisplatin but in none of the selective infusion patients. Seizures and/or transient or permanent neurologic deterioration occurred in four patients (27%) after ICA cisplatin and in 11 patients (44%) after selective intracerebral infusion. CONCLUSIONS: Although this was not a randomized comparison, selective intracerebral artery cisplatin infusion in this group of patients reduced the risk of eye toxicity, but did not produce a better tumor response rate, and carried a higher risk of neurotoxicity relative to ICA infusion.


Subject(s)
Carotid Arteries , Cerebral Arteries , Cisplatin/administration & dosage , Glioma/drug therapy , Neoplasm Recurrence, Local/drug therapy , Supratentorial Neoplasms/drug therapy , Adult , Cisplatin/adverse effects , Humans , Infusions, Intra-Arterial , Injections, Intra-Arterial , Middle Aged , Treatment Outcome
12.
Cancer ; 79(4): 804-12, 1997 Feb 15.
Article in English | MEDLINE | ID: mdl-9024719

ABSTRACT

BACKGROUND: Pituitary carcinomas are rare adenohypophysial neoplasms, the definition, diagnosis, therapy, and prognosis of which are controversial. METHODS: Pituitary carcinomas were defined as primary adenohypophysial neoplasms with documented craniospinal and/or systemic metastases. The authors report a clinicopathologic study of 15 examples examined by light microscopy, immunohistochemistry, and image analysis. Both proliferative activity and p53 tumor suppressor gene expression were studied. RESULTS: The study group consisted of 15 patients, including 8 males and 7 females ranging in age from 34-71 years (mean, 56 years). Of these patients, seven had adrenocorticotropic hormone (ACTH)-producing tumors (four in the context of Nelson's syndrome), seven had prolactin-producing tumors, and one had a nonfunctioning tumor. No evidence of diabetes insipidus was seen in any case. Fourteen tumors were initially considered macroadenomas. Of the ten cases for whom tumor extent was known, all had invasive tumors. The interval from the initial diagnosis of adenoma to that of carcinoma ranged from 0.3 to 18.0 years (mean, 6.6 years; median, 5.0 years); the longest mean interval (15.3 years) occurred for patients with Nelson's syndrome. The latency was twice as long for ACTH-producing tumors as for prolactin (PRL) cell tumors (9.5 vs. 4.7 years). All carcinomas showed a greater tendency toward systemic metastasis than craniospinal metastasis; the rate of systemic metastasis was 71% for PRL cell tumors and 57% for ACTH-producing tumors. Thirteen percent of tumors showed both patterns of metastasis. Fully 50% of primary tumors and the majority of metastases showed nuclear pleomorphism and/or hyperchromasia. The mean mitotic, MIB-1, and proliferating cell nuclear antigen indices for primary tumors and metastases were as follows: 2/10 high-power field (hpf), 2.6% and 11%, respectively; 6/10 hpf, 7.8% and 16%, respectively. Staining for p53 protein was noted in 57% of primary tumors and 88% of metastatic tumors; a relative increase in p53 expression in metastases was noted in 83%. All but one of the primary and metastatic tumors were aneuploid. The most common treatments were radiation therapy and, for PRL cell carcinomas, dopamine agonist administration. Both treatments provided only palliation. Eighty percent of the patients died of metastatic disease 7 days to 8 years after the diagnosis of carcinoma; of these, 66% died within 1 year. At last follow-up, 20% of patients were alive with metastases 9-18 months after diagnosis. CONCLUSIONS: Nearly all pituitary carcinomas present as functioning, microscopically atypical or mitotically active, invasive macroadenomas. By definition, after an interval related to their immunotype, all metastasize. The tumors show a greater tendency toward systemic metastasis than craniospinal metastasis and are associated with poor prognosis. Radiation and dopamine agonist therapy generally provide only palliation. Proliferation indices and p53 expression tend to be higher in metastases than in primary tumors. The current definition of pituitary carcinoma requires the demonstration of metastasis; however, high mitotic and MIB-1 labeling indices as well as p53 immunoreactivity suggest the diagnosis and appear to be of prognostic significance. A redefinition of aggressive pituitary tumors is proposed--one that facilitates the recognition of tumors prone to metastasis.


Subject(s)
Carcinoma , Pituitary Neoplasms , Adrenocorticotropic Hormone/metabolism , Adult , Aged , Carcinoma/metabolism , Carcinoma/pathology , Carcinoma/therapy , Female , Humans , Immunohistochemistry , Male , Middle Aged , Pituitary Neoplasms/metabolism , Pituitary Neoplasms/pathology , Pituitary Neoplasms/therapy , Prolactinoma/pathology , Prolactinoma/therapy
13.
Ann Thorac Surg ; 61(6): 1823-4, 1996 Jun.
Article in English | MEDLINE | ID: mdl-8651794

ABSTRACT

Surgical resection of multiple pulmonary metastases from a recurrent intracranial meningioma in a 53-year-old woman is presented. The primary tumor was diagnosed in 1984 and partially excised in early 1985. The tumor recurred and was re-excised in 1989 and 1992. A fourth intracranial recurrence was noted in 1993, accompanied by multiple bilateral pulmonary metastases. The metastases were excised using staged thoracotomies in July and September 1994. The patient is surviving with cranial tumor residual.


Subject(s)
Lung Neoplasms/secondary , Lung Neoplasms/surgery , Meningeal Neoplasms/pathology , Meningioma/secondary , Meningioma/surgery , Neoplasm Recurrence, Local/pathology , Female , Humans , Meningeal Neoplasms/surgery , Middle Aged , Neoplasm Recurrence, Local/surgery , Neoplasm, Residual , Reoperation , Survival Rate , Thoracotomy
14.
J Neurophysiol ; 72(2): 1028-31, 1994 Aug.
Article in English | MEDLINE | ID: mdl-7983509

ABSTRACT

1. The function of extraocular muscle proprioception in the control of eye movements is uncertain. We tested the hypothesis that proprioception contributes to the long-term regulation of ocular alignment and eye movement conjugacy. 2. Eye movements were recorded in monkeys with unilateral extraocular muscle palsies, before and after proprioceptive deafferentation of the paretic eye. Following deafferentation, ocular alignment and saccade conjugacy gradually worsened over several weeks. In contrast, disconjugate adaptation induced by habitual binocular viewing with a prism (disparity-mediated adaptation) occurred normally after deafferentation. 3. These results provide the first evidence that proprioception functions in the control of eye movements in primates, and indicate that proprioception contributes to the long-term adaptive mechanisms that regulate ocular alignment during fixation and saccades. The error signal used in this process may be derived from a mismatch between the efference copy and proprioceptive afference.


Subject(s)
Eye Movements/physiology , Oculomotor Muscles/innervation , Proprioception/physiology , Saccades/physiology , Afferent Pathways/physiology , Animals , Fixation, Ocular/physiology , Macaca mulatta , Trochlear Nerve/physiology , Vision, Binocular/physiology
17.
Neurosurgery ; 34(1): 159-62; discussion 162-3, 1994 Jan.
Article in English | MEDLINE | ID: mdl-8121552

ABSTRACT

Two men undergoing transsphenoidal exploration for pituitary adenoma were found to have lymphocytic hypophysitis. Both presented with frontal headaches, lethargy, and diminished libido. Laboratory investigations showed markedly depressed serum testosterone, and magnetic resonance imaging demonstrated pituitary enlargement, with optic chiasm involvement. Intraoperatively, the dura was adherent to the pituitary in each case. The resected glands were effaced by a dense lymphoplasmacytic infiltrate and fibrosis, without granulomas. Nonspecific peripheral enhancement on imaging suggested a diagnosis other than adenoma, but more experience with peripheral enhancement in lymphocytic hypophysitis is needed. The diagnosis was histological and required surgical intervention. Long-term pituitary replacement therapy is usually required.


Subject(s)
Autoimmune Diseases/diagnosis , Hypopituitarism/diagnosis , Lymphocytosis/diagnosis , Pituitary Diseases/diagnosis , Pituitary Gland/pathology , Adenoma/diagnosis , Adenoma/pathology , Adenoma/surgery , Adult , Autoimmune Diseases/pathology , Autoimmune Diseases/surgery , Diagnosis, Differential , Fibrosis , Humans , Hypopituitarism/pathology , Hypopituitarism/surgery , Lymphocytosis/pathology , Lymphocytosis/surgery , Magnetic Resonance Imaging , Male , Middle Aged , Pituitary Diseases/pathology , Pituitary Diseases/surgery , Pituitary Function Tests , Pituitary Gland/immunology , Pituitary Gland, Anterior/pathology , Pituitary Gland, Anterior/surgery , Pituitary Neoplasms/diagnosis , Pituitary Neoplasms/pathology , Pituitary Neoplasms/surgery , Plasma Cells/pathology
18.
Neurosurgery ; 30(6): 825-9, 1992 Jun.
Article in English | MEDLINE | ID: mdl-1614581

ABSTRACT

The criteria for brain biopsy in patients with acquired immunodeficiency syndrome (AIDS) remain unclear and without universal acceptance. In order to shed more light on this issue, the authors reviewed the records of 25 AIDS patients with focal cerebral lesions who consecutively underwent stereotactic biopsy between November 1988 and October 1990. The most frequently occurring diagnoses were lymphoma (36%), progressive multifocal leukoencephalopathy (24%), and toxoplasmosis (8%). Patients whose central nervous system disease resulted in their initial presentation (approximately 40%) survived a median of 37 weeks, as opposed to 6 weeks for those who had previous AIDS-related infections. The proportion of biopsies of contrast-enhancing lesions that were diagnostic and thereby contributed to the patients' therapeutic management was 87.5%. On the other hand, only 67% of the biopsies of nonenhancing lesions were diagnostic, and none of these lesions were treatable. All of the lymphoma patients had had AIDS for some time and, despite a reasonable preoperative Karnofsky score and postoperative radiation therapy, their median survival was only 6 weeks; however, biopsy was critical to their therapeutic management. Early brain biopsy, rather than empiric antitoxoplasmosis therapy, appears indicated for aggressive therapy of contrast-enhancing lesions in patients who have had previous manifestations of AIDS. The role for biopsy of nonenhancing lesions is less clear, but it may provide prognostic information.


Subject(s)
AIDS Dementia Complex/pathology , Brain Diseases/pathology , HIV Infections/pathology , Opportunistic Infections/pathology , Stereotaxic Techniques , Biopsy, Needle , Brain/pathology , Brain Neoplasms/pathology , Cryptococcosis/pathology , Encephalitis/pathology , Glioma/pathology , Herpes Simplex/pathology , Humans , Leukoencephalopathy, Progressive Multifocal/pathology , Lymphoma/pathology , Tomography, X-Ray Computed , Toxoplasmosis, Cerebral/pathology
19.
Clin Neurosurg ; 38: 112-131, 1992.
Article in English | MEDLINE | ID: mdl-1537183

ABSTRACT

Frame-based stereotactic systems provide valuable localization information for the performance of neurosurgical procedures. State-of-the-art systems provide for sophisticated preoperative planning and intraoperative interactive help with resection of predefined tissue volumes, providing assistance with resection of intrinsic brain tumors whose margins may not be readily visible at the time of surgery. There remain, however, a majority of neurosurgical procedures that would benefit from some form of localization but for which the application of a cumbersome frame and arc system is inconvenient. Frameless stereotactic localization or "cranial-based" localization provides a rapid and convenient means for computer-interactive localization and surgery for many of these cases. The stereotactic operating arm system is designed to complement frame-based stereotactic surgery, bringing standard neurosurgical procedures into the realm of computer-assisted interactive localization. The pace of progress is such that eventually, some form of computer interactive cranial localization will become a common neurosurgical tool. The concept of frameless localization is taken a step further in the frameless radiosurgical system described above. It is reasonable to think that this concept of "automated feature recognition," whether for recognizing scalp or bone contours, will ultimately become the foundation of procedures requiring cranial localization with reference to previously obtained digital images.


Subject(s)
Brain Diseases/surgery , Brain Neoplasms/surgery , Stereotaxic Techniques/instrumentation , Tomography, X-Ray Computed/instrumentation , Adult , Craniopharyngioma/surgery , Female , Humans , Hydrocephalus/surgery , Male , Middle Aged , Pituitary Neoplasms/surgery
20.
Neurosurg Clin N Am ; 1(1): 37-48, 1990 Jan.
Article in English | MEDLINE | ID: mdl-2135972

ABSTRACT

Low-grade gliomas (grades I and II) are infiltrative lesions. Patients harboring these tumors follow extremely variable clinical courses. Review of current data suggests that in patients with large tumors, complete excision affords long-term survival, with or without radiation therapy. Partial excision should be followed by radiation therapy. The management of very small tumors in patients who are neurologically normal is controversial. Stereotactic technique is particularly useful in diagnosis, and often in tumor resection, in this group of patients.


Subject(s)
Glioma , Supratentorial Neoplasms , Combined Modality Therapy , Craniotomy/methods , Glioma/diagnosis , Glioma/epidemiology , Glioma/therapy , Humans , Supratentorial Neoplasms/diagnosis , Supratentorial Neoplasms/epidemiology , Supratentorial Neoplasms/therapy
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