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T C Spoor

Publications and source records attributed to T C Spoor.

At least 19 recordsLinked to original sources
PubMed2001

Histopathology and ultrastructural examination of optic nerve sheath biopsies after optic nerve sheath decompression with and without mitomycin.

PURPOSE: We chose to compare histologically and ultrastructurally changes in the optic nerve sheath after optic nerve sheath decompression, initially after a second surgery and after treatment with mitomycin-C. The mechanism by which optic nerve sheath decompression alleviates papilledema can be further understood in consideration of the results. METHODS: Tissue was obtained by biopsy from 3 first-time surgical and 4 reoperative cases with and without mitomycin-C in patients with idiopathic intracranial hypertension. The sheaths were fixed in a mixture of 2% paraformaldehyde and 2% glutaraldehyde, osmicated and dehydrated in a series of ethanol, and finally embedded in epon. Tissue blocks were sectioned at 1 microm and stained with both PPD and toluidine blue. Thin sections were examined by transmission electron microscopy. RESULTS: Normal meningeal tissue obtained at the time at optic nerve sheath decompression consisted mainly of collagen, closely packed and roughly parallel to the axis of the optic nerve. Collagen deposition seen in scar tissue after secondary optic nerve sheath decompression was extremely disorganized and irregular, with the individual fibers laid down seemingly at random. There was little sense of layering or of parallel arrays. Mitomycin-C appeared to influence collagen deposition in such a way that the collagen was more regularly packed and more closely resembled unoperated tissue. CONCLUSIONS: The regular well-organized collagen packing seen in normal sheath tissue is disrupted and replaced by less organized but compact scar tissue after optic nerve sheath decompression. With mitomycin use, more regular collagen packing closely approximating that found in unoperated sheath occurs. This configuration of fibers lends support for the filtration mechanism of optic nerve sheath decompression in treating papilledema.

Antibiotics, Antineoplastic↗
PubMed2001

Acinic cell carcinoma of the lacrimal gland with intracranial extension: a case report.

PURPOSE: To describe a patient with acinic cell carcinoma of the lacrimal gland presenting with atypical manifestations including erosion of the orbital roof and intracranial extension. We compare his clinical manifestations with two previously reported cases. METHODS: Case report. RESULTS: A 51-year-old man presented with a firm, tender, palpable mass in the superior temporal portion of his right orbit. CT scan demonstrated a large homogeneously enhancing mass displacing the globe inferiorly and eroding the roof of the orbit. MRI of the orbit showed intracranial extension of tumor. Biopsy revealed an acinic cell carcinoma of the lacrimal gland. CONCLUSIONS: Acinic cell carcinoma is a rare neoplasm occurring primarily in the major and minor salivary glands.

Carcinoma, Acinar Cell↗
PubMed1996

Subtenon's local anesthesia for optic nerve sheath fenestration.

PURPOSE: We used subtenon's local anesthesia for optic nerve sheath fenestration as an alternative to either general or retrobulbar anesthesia. METHODS: Thirty patients with pseudotumor cerebri, who were unresponsive to medical treatment, underwent optic nerve sheath fenestration after administration of topical and subtenon's local anesthesia. RESULTS: When topical tetracaine, in conjunction with subtenon's anesthesia, was administered at the beginning of the procedure, excellent anesthesia and maximal patient comfort were achieved. CONCLUSIONS: The use of local anesthesia allows for a pain-free, expeditious operation with fewer potential anesthetic complications.

Anesthesia, Local↗
PubMed1996

Incidence of ptosis following trabeculectomy: a comparative study.

The occurrence of ptosis after trabeculectomy has been a common postoperative complication. Many factors have been implicated in the development of postoperative ptosis. The purpose of this study was to investigate the incidence of ptosis following trabeculectomy and whether or not it was influenced by combined cataract surgery, type of conjunctival flap, and previous intraocular surgery. We reviewed 386 eyes of 386 patients who underwent either trabeculectomy alone or trabeculectomy combined with cataract surgery, with greater than 6 month follow-up. Ptosis occurred in 10.7% (18 of 150 eyes) after trabeculectomy alone and in 12.7% (30 of 236 eyes) after trabeculectomy with combined cataract surgery (p = 0.96). The incidence of ptosis was 12.3% (10 of 81 eyes) after limbus-based conjunctival flap and 12.5% (38 of 305 eyes) after fornix-based conjunctival flap (p = 0.98). There was no significant difference in the incidence of ptosis between primary surgery eyes (12.5%, 34 of 273 eyes) and secondary surgery eyes (12.4%, 14 of 113 eyes) (p = 0.97). The incidence of ptosis after trabeculectomy was about 12% overall and not significantly influenced by combined cataract surgery, type of conjunctival flap or previous ocular surgery.

Adolescent↗
PubMed1996

Management of traumatic optic neuropathy.

Visual loss caused by trauma to the optic nerve is a well-recognized sequela to cranio-maxillofacial trauma. The authors reviewed their experience with 90 patients with pure traumatic optic neuropathy and optic nerve trauma with concomitant maxillofacial injuries. All patients were treated with intravenous steroids. Those not improving underwent extracranial optic canal decompression. Patients with initial visual acuity of 20/100 or better all responded favorably with improvement in visual acuity or visual field to a course of intravenous megadose corticosteroids. Patients with initial vision of 20/200 or worse who failed to respond to corticosteroids may have improved visual function after undergoing extracranial optic canal decompression. Preoperative and postoperative computed tomography scans on 6 patients enhanced with intrathecal iopamidol indicate the site of optic nerve compression to be at the optic canal. This article discusses the diagnosis and the medical and surgical treatment of pure and complex optic nerve injuries.

Adult↗
PubMed1995

Long-term results using adjunctive mitomycin C in optic nerve sheath decompression for pseudotumor cerebri.

PURPOSE: Up to 35% of patients undergoing optic nerve sheath decompression (ONSD) for pseudotumor cerebri who show initial improvement in visual function later show deterioration in visual field and acuity. Although repeat surgery can result in subsequent visual improvement, these procedures are technically difficult because of scarring and fibrosis. Attempting to improve the long-term success of ONSD, the authors sought to analyze the long-term success of ONSD by pretreating optic nerve sheaths with mitomycin C before incision. METHODS: Using a standard transconjunctival medial orbitotomy, optic nerve sheaths were exposed and treated for 5 minutes with mitomycin C (0.5 mg/ml)-soaked neurosurgical cottonoids before incision. RESULTS: Both eyes undergoing repeat ONSD with adjunctive mitomycin C had initial improvement and stable visual function for follow-up of more than 3 years. Four eyes that underwent primary ONSD all initially showed improvement in visual field. Three eyes with large cysts or fistulas remained stable. Another eye had gradual decline in visual function. Repeat ONSD in this eye showed no orbital scarring, and lysis of adhesions between dura-arachnoid and optic nerve resulted in improved, stable visual function for 31 months of follow-up. CONCLUSION: Mitomycin C appears to be a safe adjunct to ONSD in a series of six patients followed between 20 and 37 months. Fistulization and cyst formation are associated with improved visual function. Closure of cysts and fistulas may result in worsening visual function due to intersheath adhesions. Repeat surgery shows significantly less orbital scarring and allows for easier and successful repeat surgery. Adjunctive mitomycin C leads to less orbital scarring after ONSD, allowing for easier repeat surgery.

Adult↗
PubMed1993

Long-term effectiveness of optic nerve sheath decompression for pseudotumor cerebri.

OBJECTIVE: To determine the long-term success of optic nerve sheath decompression in preserving visual function in patients with pseudotumor cerebri (PTC). DESIGN: To define stability of visual fields, we reviewed 32 series of postoperative visual fields in patients who were undergoing optic nerve sheath decompression for PTC who had stable visual acuity and four or more fields during 6 to 60 months of follow-up. The SD of these series was 0.80 dB (+/- 0.39 dB) of mean deviation. Fluctuations within 2 SDs of the 1-month postoperative field were +/- -1.60 dB. We therefore defined stability as a mean deviation within 2 dB of the preoperative visual field; improvement, greater than 2-dB mean deviation, and worsening, less than 2-dB mean deviation. We then extended our review to include all patients (54 patients, 75 eyes) who underwent optic nerve sheath decompression for PTC, who were followed up with serial automated perimetry (Humphrey 30-2). RESULTS: Fifty-one eyes (68%) showed improvement (36%) or stabilization (32%) of visual function. Twenty-four eyes (32%) experienced deterioration of visual function after an initially successful optic nerve sheath decompression. The probability of failure from 3 to 5 years was .35 by life-table analysis. CONCLUSION: Optic nerve sheath decompression effectively stabilizes or improves visual function in the majority of patients with PTC and visual loss. However, it may fail at any time after surgery. Patients with PTC need to be followed up routinely with automated perimetry to detect deterioration of visual function.

Adolescent↗
PubMed1993

Progressive and static nonarteritic ischemic optic neuropathy treated by optic nerve sheath decompression.

PURPOSE: Optic nerve sheath fenestration has been advocated as an effective treatment for progressive nonarteritic ischemic optic neuropathy (NAION) and anecdotally effective for selected patients with NAION who have not had progressive visual loss. To determine whether optic nerve sheath decompression is of any benefit in patients with NAION, the authors reviewed their experience, surgically treating 23 patients with progressive NAION and 15 patients with static or nonprogressive NAION. RESULTS: Patients with progressive NAION had a significant improvement in visual function as measured by Snellen visual acuity after optic nerve sheath decompression (P = 0.0005). There was no statistically significant improvement in visual field mean deviation (P = 0.11). The 15 patients undergoing optic nerve sheath decompression for static NAION failed to demonstrate significant improvement in either visual acuity (P = 0.90) or visual field mean deviation (P = 0.87). Preoperative standardized echography was used to measure the optic nerve sheath diameter and ascertain its compressibility (30 degrees test). There was a significant difference in compressibility between eyes with static NAION and eyes with progressive NAION (P = 0.001). Accumulation of optic nerve sheath fluid was documented in three eyes initially presenting with NAION and then with development of progressive visual dysfunction. CONCLUSION: Optic nerve sheath decompression improves visual acuity but has little effect on overall visual function in patients with progressive NAION. Optic nerve sheath decompression does not improve visual field or acuity in patients with static NAION. Detection of significant intrasheath fluid by standardized echography helps to objectively differentiate patients with NAION who may benefit from optic nerve sheath decompression.

Adult↗
PubMed1992

Visual field defects in patients with normal-tension glaucoma and patients with high-tension glaucoma.

We compared the automated visual field test results of 24 patients with normal-tension glaucoma and 24 patients with high-tension glaucoma who were closely matched for the amount of visual field loss to determine any differences in the characteristics of visual field defects between the two groups. Patients were matched with a maximum allowable difference in mean deviation of 0.3 dB. Although the normal-tension group had a greater amount of focal visual field loss (pattern standard deviation), the difference was not statistically significant (P = .628). Additionally, there was no statistically significant difference in the amount of diffuse or focal visual field damage in the superior hemifields between the two groups; however, the patients with normal-tension glaucoma had a significantly greater amount of localized visual field loss in the inferior hemifield than the patients with high-tension glaucoma (P = .015). Our data support the hypothesis that a vascular mechanism may have a greater role in the pathogenesis of optic nerve damage and visual field loss in patients with normal-tension glaucoma than in patients with high-tension glaucoma.

Aged↗
PubMed1992

Quantitative evaluation of optic disc pallor in pseudotumor cerebri patients.

We quantified optic disc pallor in patients with pseudotumor cerebri with the Rodenstock Optic Nerve Head Analyzer before and after optic nerve sheath decompression. Mean frequency distribution of pallor peaked between the pallor values of 0.10 and 0.20 in four pseudotumor cerebri patients and between 0.50 and 0.60 in five normal subjects. The red dominant pallor reflectance in pseudotumor cerebri patients decreased significantly and shifted toward the reflectance of normal subjects gradually during the 9 weeks after successful optic nerve sheath decompression, coinciding with the ophthalmoscopic resolution of papilledema. The computerized pallor measurement with the Rodenstock Optic Nerve Head Analyzer allows an objective and quantitative assessment of papilledema in pseudotumor cerebri patients.

Adult↗