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P J Patel

Publications and source records attributed to P J Patel.

At least 19 recordsLinked to original sources
PubMed2006

Intravitreal triamcinolone acetonide for macular oedema owing to retinal vein occlusion.

PURPOSE: To assess the long-term safety and efficacy of intravitreal triamcinolone acetonide injection in the management of macular oedema caused by central, hemi-, and branch retinal vein occlusion (CRVO, HRVO, or BRVO). METHODS: This prospective, interventional case series included 13 patients (13 eyes) with retinal vein occlusion and macular oedema. They received an intravitreal injection of 4 mg triamcinolone acetonide. Follow-up was for 1 year with repeat injections where appropriate. Outcome measures were visual acuity and macular thickness measured using ocular coherence tomography (OCT). RESULTS: There were four patients with CRVO, one with HRVO, and eight with BRVO (13 eyes). Mean duration of symptoms before intravitreal triamcinolone acetonide injection was 6.8 months (SD 4.5 months). Eight eyes (62%) responded well with improved visual acuity and macular thickness 1-3 months postinjection. All eight eyes developed recurrent macular oedema and five received repeat injections. Three patients declined a second injection. No improvement in visual acuity or OCT macular thickness was seen after the second injection with visual acuity returning to baseline levels at 1-year follow-up. Three eyes (23%) showed no response to the initial injection (no improvement in macular thickness or visual acuity). Seven patients (54%) had a rise in intraocular pressure with six (46%) requiring treatment. CONCLUSIONS: Intravitreal injection of triamcinolone acetonide is effective as a short-term treatment of macular oedema owing to retinal vein occlusion, improving both visual acuity and macular thickness. However, this effectiveness is not maintained after 1 year despite repeat injections.

Aged↗
PubMed2002

Spontaneous thoracic duct cyst.

Spontaneous and asymptomatic supraclavicular thoracic duct cysts (lymphoceles ) are rare. Only five cases have been reported so far. They are more common after surgery or trauma and have been reported in the abdomen, mediastinum, pelvis and neck. They must be differentiated from other neck cysts as failure to recognise their attachment may result in the disastrous consequence of chylothorax. A high index of suspicion is necessary, and diagnosis usually can be established by fine-needle aspiration and suitable imaging. This case is reported along with a review of the literature and management options, including that of inadvertent damage to the thoracic duct.

Aged↗
PubMed2001

Long-term survival after ablation of the atrioventricular node and implantation of a permanent pacemaker in patients with atrial fibrillation.

BACKGROUND: In patients with atrial fibrillation that is refractory to drug therapy, radio-frequency ablation of the atrioventricular node and implantation of a permanent pacemaker are an alternative therapeutic approach. The effect of this procedure on long-term survival is unknown. METHOD: We studied all patients who underwent ablation of the atrioventricular node and implantation of a permanent pacemaker at the Mayo Clinic between 1990 and 1998. Observed survival was compared with the survival rates in two control populations: age- and sex-matched members of the Minnesota population between 1970 and 1990 and consecutive patients with atrial fibrillation who received drug therapy in 1993. RESULTS: A total of 350 patients (mean [+/-SD] age, 68+/-11 years) were studied. During a mean of 36+/-26 months of follow-up, 78 patients died. The observed survival rate was significantly lower than the expected survival rate based on the general Minnesota population (P<0.001). Previous myocardial infarction (P<0.001), a history of congestive heart failure (P=0.02), and treatment with cardiac drugs after ablation (P=0.03) were independent predictors of death. Observed survival among patients without these three risk factors was similar to expected survival (P=0.43). None of the 26 patients with lone atrial fibrillation died during follow-up (37+/-27 months). The observed survival rate among patients who underwent ablation was similar to that among 229 controls with atrial fibrillation (mean age, 67+/-12 years) who received drug therapy (P=0.44). CONCLUSIONS: In the absence of underlying heart disease, survival among patients with atrial fibrillation after ablation of the atrioventricular node is similar to expected survival in the general population. Long-term survival is similar for patients with atrial fibrillation, whether they receive ablation or drug therapy. Control of the ventricular rate by ablation of the atrioventricular node and permanent pacing does not adversely affect long-term survival.

Adult↗
PubMed2001

Sarcoidosis.

UNLABELLED: Sarcoidosis is a systemic noncaseating granulomatous disorder of unknown origin. The cutaneous manifestations of sarcoidosis often enable the dermatologist to be the first physician to make the diagnosis. This article reviews essential sarcoidosis pathophysiology, clinical polymorphisms, systemic evaluation, and treatment modalities for cutaneous sarcoidosis to further enhance the dermatologist's understanding of this disease entity. LEARNING OBJECTIVE: At the conclusion of this learning activity, participants should be familiar with the theories of the pathogenesis of sarcoidosis, its cutaneous manifestations, its various syndromes and associations, and its presentation in children. Participants should also be more knowledgeable about diagnostic evaluation, measurement of disease progression, treatment modalities, and the prognosis and mortality data of sarcoidosis.

Humans↗
PubMed2000

Metastatic endometrial carcinoma of the neck.

We report a case of metastatic endometrial carcinoma of the neck. A patient with a past medical history of squamous cell carcinoma of the larynx, breast carcinoma and endometrial carcinoma presented with a neck mass. Fine needle aspiration cytology (FNAC) showed this to be a poorly differentiated carcinoma with squamoid features and thus a potentially curative neck dissection was performed. Histology of the mass showed a clear cell endometrial carcinoma. Metastatic gynacecological malignancies to the head and neck are rare and this is the first reported case of metastatic endometrial carcinoma in the neck.

Aged↗
PubMed2000

Pharyngeal pouch surgery: a five year review.

The treatment of pharyngeal pouch varies widely. Our aim was to establish current and recent practice in pharyngeal pouch surgery in our department and set guidelines for future management. A retrospective audit over a 5-year period was performed with all data derived from patient notes. 28 procedures were performed on 24 patients with a mean age of 72 years. Over two thirds of these patients (68%) underwent an endoscopic procedure (stapling or diathermy) and the remainder underwent excision (14%), inversion (10%), cricopharyngeal myotomy (4%) or dilatation (4%). The primary diagnostic investigation performed was a barium swallow in 17 cases, but in 7 cases, referred by gastroenterologists, an oesophagogastroscopy was performed despite characteristic presenting features in all cases. The average inpatient stay was similar for endoscopic and excision procedures (5.5 and 5 days respectively), but longer for inversion procedures (9 days). This was influenced mainly by operative complications. 2 endoscopic stapling procedures were complicated by perforations and 1 patient developed hoarseness after an inversion procedure. The mean follow up time was one month at which stage all asymptomatic patients were discharged. 2 patients treated by endoscopic stapling and 1 patient treated by inversion complained of persistent symptoms and required further surgery. We conclude that endoscopic stapling was the commonest procedure used. Concerning future management, the use of nasogastric tubes after uncomplicated stapling procedures was abandoned. Also it was felt that large pouches should be treated by excision, small pouches by cricopharyngeal myotomy and the remainder by endoscopic stapling. The long-term evaluation of results was also deemed necessary.

Aged↗
PubMed1999

Neutrophil chemokine production in the skin following scald injury.

The present study was conducted to determine whether local production of neutrophil chemoattractant cytokines preceded the influx of neutrophils following dermal scald injury. To accomplish this, dermal tissue was examined for inflammatory infiltrate and the level of KC, a murine homolog of human interleukin-8, at various time points after scald injury. The studies reveal that there was a largely neutrophilic infiltrate at 1 day post-injury which persisted for 4 days. Dermal KC levels increased significantly at 4 h, returned to baseline at 8 h and were elevated again from 1 to 3 days post-burn (P < 0.01). At 3 days post-burn, KC was elevated 15-fold above the level in sham treated mice (P < 0.01). These observations demonstrate that the influx of neutrophils into the skin follows the expression of KC in the skin. This suggests that it should be possible to alter neutrophil accumulation at the wound site by manipulating the local chemokine signal.

Animals↗
PubMed1999

Elevation in pulmonary neutrophils and prolonged production of pulmonary macrophage inflammatory protein-2 after burn injury with prior alcohol exposure.

Various studies have shown that alcohol exposure before thermal injury leads to increased morbidity and mortality. Pulmonary failure is a major complication seen in these patients. This study examines the effects of prior alcohol exposure on lung pathology after burn injury. There is a marked increase in neutrophil recruitment in the lung after thermal injury, and herein we show that this appears to be significantly elevated in animals given alcohol before burn injury. Consequently, we chose to determine whether there is a difference in pulmonary production of macrophage inflammatory protein (MIP)-2, a potent neutrophil chemoattractant, in mice subjected to a 15% total body surface area scald (or sham) injury with or without prior ethanol treatment. Lung tissue was obtained at various time points after injury and homogenates were assayed for MIP-2 by enzyme-linked immunosorbent assay. At 2 h after injury, peak levels of the chemokine were produced in both burn and burn + alcohol-treated mice. This represents a 7-fold increase above baseline. In mice exposed to burn injury alone, the level of MIP-2 returned to baseline within 8 h. In contrast, mice given alcohol before burn injury continued to show elevated levels of the chemokine at 8 h, after which MIP-2 decreased. This study may provide a basis for understanding the mechanism responsible for the increased neutrophil presence in the lung after thermal injury in individuals who have consumed alcohol. Subsequently, this may lead to the enhanced neutrophil-mediated pulmonary damage observed in these patients.

Alcohol Drinking↗
PubMed1998

Cutis verticis gyrata: its computed tomographic demonstration in acromegaly.

A retrospective review of the 17 cases of acromegaly, recorded in the hospital and with available CT scans was undertaken in order to determine the presence and of cutis verticis gyrata (CVG) frequency, and the spectrum of other associated radiographic appearances of CVG. The hormone levels were analysed, and the histopathology of the surgical specimens reviewed. Five cases were uncovered. In these, the scalp in CVG was markedly thickened with convoluted, gyriform or cog-wheel appearances. There was no correlation in the age, sex, duration of symptoms or the hormone levels in these two groups of acromegalics: with or without CVG. All cases were histologically pituitary adenoma. It is concluded that CVG is not uncommon in acromegaly. Its presence on a CT scan should caution the radiologist to the presence of pituitary adenoma or any of the other neurological causes of CVG.

Acromegaly↗
PubMed1996

Renal sonographic patterns in Bartter's syndrome.

The renal sonographic findings in ten cases of Bartter s syndrome investigated at the King Khalid University Hospital, Riyadh, Saudi Arabia are described. There were various sonographic abnormalities other than those of hyperechoic pyramids as previously described. These were diffuse increased renal echogenicity and hyperechoic echogenicity in the kidneys with the exception of the pyramids. This condition can be suspected early if nephrocalcinosis is present in a child with a history of polyhydramnios and premature delivery.

Bartter Syndrome↗
PubMed1996

Correlation of in vivo topical efficacies with in vitro predictions using acyclovir formulations in the treatment of cutaneous HSV-1 infections in hairless mice: an evaluation of the predictive value of the C* concept.

The purpose of this study was to carry out an extensive examination of the C* concept for prediction of the topical antiviral efficacies of acyclovir (ACV) formulations in a hairless mouse model for the treatment of cutaneous herpes simplex virus type-1 (HSV-1) infections. This method is based on estimation of the free drug concentration at the target site (C*), which is presumed to be the basal cell layer of the epidermis. Five different formulations (containing 5% ACV) were examined in a finite dose multiple dosing regimen (twice a day application) to simulate the clinical situation. For determination of C*, in vitro ACV fluxes across the hairless mouse skin were measured in an in vivo-in vitro experimental design that approximated the in vivo antiviral treatment protocol. Then, the in vivo antiviral efficacies were measured using a 1-day delayed (after HSV-1 virus inoculation) 4-day treatment protocol. 10 microL/cm2 dose of ACV formulation was applied every 12 h for 4 days after which the lesions were scored and efficacies were calculated. Our results indicate that, over a wide range of efficacies, the predictions based on C* (estimated from the experimental fluxes) are in good agreement with the in vivo antiviral efficacies. These studies, therefore, support the validity of the C* concept for various ACV formulations and suggest that the C* approach has potential for future practical situations.

Acyclovir↗
PubMed1995

Multiple congenital malformations in two sibs reminiscent of hydrolethalus and pseudotrisomy 13 syndromes.

We report on two sibs, born to consanguineous parents, with defects of the midline including cleft lip and palate, flat nose, hypotelorism, and dysgenesis of corpus callosum, in addition to short limbs, radiolucent tibial notch, digital anomalies, ambiguous genitalia, and hypopituitarism. In spite of the similarities between this condition and the hydrolethalus and pseudotrisomy 13 syndromes, our patients had neither preaxial nor postaxial polydactyly, but had previously undescribed bilateral radiolucent tibial notch, which is not known to be part of those two syndromes. The cases presented here may very well represent a new autosomal recessive syndrome.

Abnormalities, Multiple↗
PubMed1995

Adrenoleukodystrophy: CT and MRI findings.

A case of adrenoleukodystrophy (ALD) with CT and MRI findings is described. The CT scan showed low densities in the white matter of the parietal and occipital lobes. No calcifications were seen. Post-contrast CT showed an abnormal enhancement within the involved white matter. MRI showed changes of demyelination around the atria of the lateral ventricles bilaterally involving the posterior aspect of the cerebrum symmetrically. The posterior part of the posterior corpus callosum, splenium and pyramidal tracts also showed increased signal intensity. From a review of the literature, these findings are typical of the radiological changes seen in ALD. ALD can be diagnosed from typical history and biochemical changes as well as from CT and MRI findings.

Adrenoleukodystrophy↗
PubMed1995

Ambiguous genitalia: comparative role of pelvic ultrasonography and genitography.

Ambiguous genitalia represents a true medical and social emergency which needs a multi-disciplinary team approach for elucidation. The paediatric radiologist plays an important role in defining the genital anatomy which remains one of the most important factors in sex determination. Aiming to compare the predictive value of pelvic ultrasonography and genitography in sex determination in patients with ambiguous genitalia, we retrospectively reviewed the medical records of 69 patients, 53 females and 16 males, where both procedures were employed. In female pseudohermaphroditism, the presence of a uterus with or without vagina was predicted in 46 (86.8%) patients by ultrasound compared with 44 (83%) patients in whom a genitogram revealed a vagina +/- uterus. In six (11.3%) patients, a genitogram revealed a male-type urethra. The combination of ultrasound and genitogram, however, was more sensitive and predicted the presence of a uterus with or without vagina in 52 (98.1%) patients. In male pseudo-hermaphroditism, there was no false positive by ultrasound, and a genitogram revealed a male-type urethra in 12 (75%) patients. In conclusion, although real time pelvic ultrasonography is less invasive than genitography, its yield in elucidating genital anatomy is comparable. The combination of both procedures is more informative and has a better yield.

Child↗
PubMed1994

Symmetrical lesions in the basal ganglia.

Bilateral and symmetrical non-space occupying lesions in the basal ganglia of 27 cases were studied. Nine cases had low attenuation lesions while the remaining 18 had high attenuation lesions due to bleeding or calcifications. The clinical presentations and final diagnosis were collated and related to these changes. In the low-attentuation cases, definite hypoxic-ischaemic insults were the aetiological basis for low attenuation lesions in 3 cases; and hypothesised to be the basis in the remaining six. Amongst the high attenuation group, bleeding was noted in 4 cases with trauma or cardiac arrest. The remainder had calcifications. It is suggested that a hypoxic-ischaemic pathophysiological phenomenon might have also accounted for some of these calcifications. The co-existence of both low and high attenuation lesions in the same patients in some of our cases tends to lend credence to this hypothesis.

Adult↗
PubMed1993

Inhibition and inactivation of presynaptic cholinergic markers using redox-reactive choline analogs.

Inhibition and inactivation of two presynaptic cholinergic "markers", choline acetyltransferase and high affinity choline transporter, has been investigated using inhibitors designed with a redox-reactive catechol tethered to a quaternary ammonium group. Two quaternary ammonium alkyl-substituted catechols, 3[(trimethylammonio)methyl]catechol (TMC, 1) and N,N-dimethylepinephrine (catecholine, 2) were shown to bind weakly and noncompetitively to bovine choline acetyltransferase yet inactivated the enzyme in a time course consistent with the involvement of early intermediates in the spontaneous oxidation of these catechols. Both agents also inhibited high-affinity choline uptake. The time course of TMC and catecholine spontaneous oxidation-dependent inactivation of high affinity choline uptake sites was slower than, if it occurred at all, the spontaneous degradation of measurable choline transport in synaptosomes. When compared with inhibition of uptake of other neurotransmitters, it was shown that catecholine demonstrated more selectivity than TMC toward inhibition of choline transport. Km (microM) and Vmax (pmol/min per mg of protein) were measured for high affinity transport of choline, dopamine, and serotonin and were observed to be Km = 2.04 +/- 0.31, Vmax = 22 +/- 1; Km = 1.4, Vmax = 53; and Km = 0.15, Vmax = 23, respectively, in good agreement with published literature values. Ki's (mM) for catecholine and TMC, calculated from experimentally determined IC50's, were for catecholine 0.13 +/- 0.06, 0.53 +/- 0.09, and 0.39 +/- 0.10, and for TMC 0.06 +/- 0.03, 0.09 +/- 0.03, and 0.09 +/- 0.08, for choline, dopamine, and serotonin transport, respectively. In vivo studies using catecholine suggest that this compound impairs learning ability associated with long-term memory. Thus, catecholine represents a lead compound in a potential series of redox-reactive choline analogs, which may become useful irreversible antagonists of the critical cholinergic macromolecular targets underlying cholinergic hypofunction in disorders such as Alzheimer's disease.

Animals↗