The following relates generally to measuring a patients O.sub.2 level with a mote implanted in the patient's tissue. For example, a mote implanted in a patients tissue may be powered by ultrasound (US) signals generated by an ultrasound interrogator that is external to the patient. Components on the mote may be duty cycled off to advantageously decrease power consumption. A luminescence sensor on the mote may be used to measure the O.sub.2 level, and the luminescence sensor may be optically isolated from the patients tissue by an opaque material such as black silicon.

An apparatus can have a computing component. The computing component can be configured to receive a wireless transmission from an implanted device, verify an identity of the implanted device by verifying security data from the implanted device, and perform an authentication procedure, in response to verifying the identity of the implanted device, to determine whether the transmission is authentic by determining whether a digital signature of the transmission is authentic. The apparatus can be configured to wirelessly charge the implanted device in response to the computing component determining that the digital signature is authentic.

A system for detecting an anastomotic leak includes a sensor assembly implanted at an anastomosis site. The system also includes a reader configured to receive sensor signals from the sensor assembly and a computing device configured to communicate with the reader. The computing device may be configured to analyze the sensor signals to determine a status of the anastomosis site.

The invention relates to an active implantable medical device comprising a processing unit able to be alternately operated during a predetermined period of activity and on standby during a standby period in a cyclical manner, and means for acquiring data relating to physiological and/or physical activity. The device also comprises means for calculating a frequency analysis of the data acquired, said calculating means being capable of successively perform part of the frequency analysis during periods of activity of the processing unit.

Described herein is an implantable device configured to detect impedance characteristic of a tissue. In certain exemplary devices, the implantable device comprises (a) an ultrasonic transducer configured to emit an ultrasonic backscatter encoding information relating to an impedance characteristic of a tissue based on a modulated current flowing through the ultrasonic transducer; (b) an integrated circuit comprising (i) a variable frequency power supply electrically connected to a first electrode and a second electrode; (ii) a signal detector configured to detect an impedance, voltage, or current in a circuit comprising the variable frequency power supply, the first electrode, the second electrode, and the tissue; and (iii) a modulation circuit configured to modulate the current flowing through the ultrasonic transducer based on the detected impedance, voltage, or current; and the first electrode and the second electrode configured to be implanted into the tissue in electrical connection with each other through the tissue. Further described are systems including one or more implantable devices and an interrogator for operating the implantable device, methods of measuring impedance characteristic of a tissue in a subject, and methods of monitoring or characterizing a tissue in a subject.

Apparatus and methods for mitigation and control of inflammatory responses during usage of an implantable sensor device. In one exemplary embodiment, the implantable sensor device includes a drug-eluting component configured to release a varying amount of anti-inflammatory substance(s) (such as corticosteroid) over the lifetime of the implant, such as according to a desired elution profile. In one variant, this component is also an analyte-permeable membrane used as part of a detector of the implant. Inhibition of inflammation in the tissue improves availability of analytes (such as oxygen and glucose) to the sensor in addition to reducing fibrous encapsulation. Various modifications to the elution rate, and configuration of the implant, allow optimized control over undesirable effects such as foreign body reactions (FBR) or other inflammatory responses which may reduce usable implant lifetime.

An implantable medical device (IMD) is provided and includes sensing circuitry coupled to electrodes. The sensing circuitry is configured to sense electrical biological signals indicative of a non-physiologic condition of interest experienced by a patient during a magnetic resonance imaging (MRI) procedure, and in the presence of an MRI scanning sequence, the MRI scanning sequence includes at least one of radio frequency (RF) or gradient fields that are in an active state for active field intervals. The device includes memory to store the biological signals and to store program instructions and includes a processor that, when executing the program instructions, is configured to: determine start times for the active field intervals when the at least one of RF or gradient fields switch to the active state and manage generation of MRI-induced-noise corrected (MRI-INC) biological signals, based on the start times for the active field intervals, by at least one of: 1) applying a blanking interval to the sensing circuitry to blank a sensing operation during at least portions of the active field interval or 2) modifying segments of the biological signal sensed during at least the portions of the active field interval, and 3) comparing biologic signal sensed during at least the portions of the active field interval to a template. The device analyzes the biological signals for an indication that the patient is experiencing the non-physiologic condition.

This invention relates to an aneurysm occluder, and more particularly but not exclusively, to an endovascular aneurysm occluder that can be inserted into an aneurysm cavity by using endovascular surgical procedures. The aneurysm occluder has a deformable housing and an absorber or material that causes blood clotting made of an absorbent material in or attached to the housing.

Various embodiment disclosed herein include a method for monitoring serum potassium in a patient. The method can include gathering cardiac electrogram data from the patient using two or more electrodes, separating the cardiac electrogram data into discrete subunits including a T-wave, aligning T-waves to create aligned discrete subunits, averaging the aligned discrete subunits to generate an average T-wave for the cardiac electrogram data, and determining a serum potassium value using the average T-wave for the cardiac electrogram data and a predetermined model relating T-wave values with serum potassium magnitudes.

Injectable biophotonic sensors, systems relating to biophotonic sensors, and methods of using the injectable biophotonic sensors and systems are described. Methods and devices for delivering injectable biophotonic sensors to a subject are described. In an embodiment, an injectable biophotonic sensor comprises a printed circuit board (PCB); a light source; a first sensing element; a second sensing element; a receiver device or a induction coil; and an outer casing, wherein the first sensing element, the second sensing element, and the receiver device or the receiver induction coil are coupled to the PCB.